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.
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
Methods and Research for Multi-Component Cutting Force Sensing Devices and Approaches in Machining
Liang, Qiaokang; Zhang, Dan; Wu, Wanneng; Zou, Kunlin
2016-01-01
Multi-component cutting force sensing systems in manufacturing processes applied to cutting tools are gradually becoming the most significant monitoring indicator. Their signals have been extensively applied to evaluate the machinability of workpiece materials, predict cutter breakage, estimate cutting tool wear, control machine tool chatter, determine stable machining parameters, and improve surface finish. Robust and effective sensing systems with capability of monitoring the cutting force in machine operations in real time are crucial for realizing the full potential of cutting capabilities of computer numerically controlled (CNC) tools. The main objective of this paper is to present a brief review of the existing achievements in the field of multi-component cutting force sensing systems in modern manufacturing. PMID:27854322
Methods and Research for Multi-Component Cutting Force Sensing Devices and Approaches in Machining.
Liang, Qiaokang; Zhang, Dan; Wu, Wanneng; Zou, Kunlin
2016-11-16
Multi-component cutting force sensing systems in manufacturing processes applied to cutting tools are gradually becoming the most significant monitoring indicator. Their signals have been extensively applied to evaluate the machinability of workpiece materials, predict cutter breakage, estimate cutting tool wear, control machine tool chatter, determine stable machining parameters, and improve surface finish. Robust and effective sensing systems with capability of monitoring the cutting force in machine operations in real time are crucial for realizing the full potential of cutting capabilities of computer numerically controlled (CNC) tools. The main objective of this paper is to present a brief review of the existing achievements in the field of multi-component cutting force sensing systems in modern manufacturing.
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
Modelling bucket excavation by finite element
NASA Astrophysics Data System (ADS)
Pecingina, O. M.
2015-11-01
Changes in geological components of the layers from lignite pits have an impact on the sustainability of the cup path elements and under the action of excavation force appear efforts leading to deformation of the entire assembly. Application of finite element method in the optimization of components leads to economic growth, to increase the reliability and durability of the studied machine parts thus the machine. It is obvious usefulness of knowledge the state of mechanical tensions that the designed piece or the assembly not to break under the action of tensions that must cope during operation. In the course of excavation work on all bucket cutting force components, the first coming into contact with the material being excavated cutting edge. Therefore in the study with finite element analysis is retained only cutting edge. To study the field of stress and strain on the cutting edge will be created geometric patterns for each type of cup this will be subject to static analysis. The geometric design retains the cutting edge shape and on this on the tooth cassette location will apply an areal force on the abutment tooth. The cutting edge real pattern is subjected to finite element study for the worst case of rock cutting by symmetrical and asymmetrical cups whose profile is different. The purpose of this paper is to determine the displacement and tensions field for both profiles considering the maximum force applied on the cutting edge and the depth of the cutting is equal with the width of the cutting edge of the tooth. It will consider the worst case when on the structure will act both the tangential force and radial force on the bucket profile. For determination of stress and strain field on the form design of cutting edge profile will apply maximum force assuming uniform distribution and on the edge surface force will apply a radial force. After geometric patterns discretization on the cutting knives and determining stress field, can be seen that at the rectangular profile appears the "clogging" phenomenon of the cutting edge and at the polygonal profile the point of application remains constant without going inside. From the finite element method done in this paper it can be concluded that the polygonal profiles made of dihedral angles are much more durable and asymmetric cups tend to have uniform tension along the entire perimeter.
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 and apparatus for suppressing regenerative instability and related chatter in machine tools
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
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.
ERIC Educational Resources Information Center
Eckes, Thomas
2017-01-01
This paper presents an approach to standard setting that combines the prototype group method (PGM; Eckes, 2012) with a receiver operating characteristic (ROC) analysis. The combined PGM-ROC approach is applied to setting cut scores on a placement test of English as a foreign language (EFL). To implement the PGM, experts first named learners whom…
Hal O. Liechty; Michael G. Shelton
2004-01-01
Abstract - This study was initiated to determine the effects of various regeneration cutting methods on forest floor mass and nutrient content in shortleaf pine-hardwood communities in the Ouachita and Ozark National Forests. Clearcutting generally altered forest floor concentrations of N, P, and S as well as loss on ignition by increasing the amount...
The adaptive, cut-cell Cartesian approach (warts and all)
NASA Technical Reports Server (NTRS)
Powell, Kenneth G.
1995-01-01
Solution-adaptive methods based on cutting bodies out of Cartesian grids are gaining popularity now that the ways of circumventing the accuracy problems associated with small cut cells have been developed. Researchers are applying Cartesian-based schemes to a broad class of problems now, and, although there is still development work to be done, it is becoming clearer which problems are best suited to the approach (and which are not). The purpose of this paper is to give a candid assessment, based on applying Cartesian schemes to a variety of problems, of the strengths and weaknesses of the approach as it is currently implemented.
Lung lobe segmentation based on statistical atlas and graph cuts
NASA Astrophysics Data System (ADS)
Nimura, Yukitaka; Kitasaka, Takayuki; Honma, Hirotoshi; Takabatake, Hirotsugu; Mori, Masaki; Natori, Hiroshi; Mori, Kensaku
2012-03-01
This paper presents a novel method that can extract lung lobes by utilizing probability atlas and multilabel graph cuts. Information about pulmonary structures plays very important role for decision of the treatment strategy and surgical planning. The human lungs are divided into five anatomical regions, the lung lobes. Precise segmentation and recognition of lung lobes are indispensable tasks in computer aided diagnosis systems and computer aided surgery systems. A lot of methods for lung lobe segmentation are proposed. However, these methods only target the normal cases. Therefore, these methods cannot extract the lung lobes in abnormal cases, such as COPD cases. To extract lung lobes in abnormal cases, this paper propose a lung lobe segmentation method based on probability atlas of lobe location and multilabel graph cuts. The process consists of three components; normalization based on the patient's physique, probability atlas generation, and segmentation based on graph cuts. We apply this method to six cases of chest CT images including COPD cases. Jaccard index was 79.1%.
Nie, Jinfang; Liang, Yuanzhi; Zhang, Yun; Le, Shangwang; Li, Dunnan; Zhang, Songbai
2013-01-21
In this paper, we report a simple, low-cost method for rapid, highly reproductive fabrication of paper-based microfluidics by using a commercially available, minitype CO(2) laser cutting/engraving machine. This method involves only one operation of cutting a piece of paper by laser according to a predesigned pattern. The hollow microstructures formed in the paper are used as the 'hydrophobic barriers' to define the hydrophilic flowing paths. A typical paper device on a 4 cm × 4 cm piece of paper can be fabricated within ∼7-20 s; it is ready for use once the cutting process is finished. The main fabrication parameters such as the applied current and cutting rate of the laser were optimized. The fabrication resolution and multiplexed analytical capability of the hollow microstructure-patterned paper were also characterized.
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.
Figure-ground segmentation based on class-independent shape priors
NASA Astrophysics Data System (ADS)
Li, Yang; Liu, Yang; Liu, Guojun; Guo, Maozu
2018-01-01
We propose a method to generate figure-ground segmentation by incorporating shape priors into the graph-cuts algorithm. Given an image, we first obtain a linear representation of an image and then apply directional chamfer matching to generate class-independent, nonparametric shape priors, which provide shape clues for the graph-cuts algorithm. We then enforce shape priors in a graph-cuts energy function to produce object segmentation. In contrast to previous segmentation methods, the proposed method shares shape knowledge for different semantic classes and does not require class-specific model training. Therefore, the approach obtains high-quality segmentation for objects. We experimentally validate that the proposed method outperforms previous approaches using the challenging PASCAL VOC 2010/2012 and Berkeley (BSD300) segmentation datasets.
Hirano, Takashi; Osaka, Taito; Sano, Yasuhisa; Inubushi, Yuichi; Matsuyama, Satoshi; Tono, Kensuke; Ishikawa, Tetsuya; Yabashi, Makina; Yamauchi, Kazuto
2016-06-01
We have developed a method of fabricating speckle-free channel-cut crystal optics with plasma chemical vaporization machining, an etching method using atmospheric-pressure plasma, for coherent X-ray applications. We investigated the etching characteristics to silicon crystals and achieved a small surface roughness of less than 1 nm rms at a removal depth of >10 μm, which satisfies the requirements for eliminating subsurface damage while suppressing diffuse scattering from rough surfaces. We applied this method for fabricating channel-cut Si(220) crystals for a hard X-ray split-and-delay optical system and confirmed that the crystals provided speckle-free reflection profiles under coherent X-ray illumination.
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.
Kwak, Kichang; Yoon, Uicheul; Lee, Dong-Kyun; Kim, Geon Ha; Seo, Sang Won; Na, Duk L; Shim, Hack-Joon; Lee, Jong-Min
2013-09-01
The hippocampus has been known to be an important structure as a biomarker for Alzheimer's disease (AD) and other neurological and psychiatric diseases. However, it requires accurate, robust and reproducible delineation of hippocampal structures. In this study, an automated hippocampal segmentation method based on a graph-cuts algorithm combined with atlas-based segmentation and morphological opening was proposed. First of all, the atlas-based segmentation was applied to define initial hippocampal region for a priori information on graph-cuts. The definition of initial seeds was further elaborated by incorporating estimation of partial volume probabilities at each voxel. Finally, morphological opening was applied to reduce false positive of the result processed by graph-cuts. In the experiments with twenty-seven healthy normal subjects, the proposed method showed more reliable results (similarity index=0.81±0.03) than the conventional atlas-based segmentation method (0.72±0.04). Also as for segmentation accuracy which is measured in terms of the ratios of false positive and false negative, the proposed method (precision=0.76±0.04, recall=0.86±0.05) produced lower ratios than the conventional methods (0.73±0.05, 0.72±0.06) demonstrating its plausibility for accurate, robust and reliable segmentation of hippocampus. Copyright © 2013 Elsevier Inc. All rights reserved.
3D-profile measurement of advanced semiconductor features by using FIB as reference metrology
NASA Astrophysics Data System (ADS)
Takamasu, Kiyoshi; Iwaki, Yuuki; Takahashi, Satoru; Kawada, Hiroki; Ikota, Masami
2017-03-01
A novel method of sub-nanometer uncertainty for the 3D-profile measurement and LWR (Line Width Roughness) measurement by using FIB (Focused Ion Beam) processing, and TEM (Transmission Electron Microscope) and CD-SEM (Critical Dimension Scanning Electron Microscope) images measurement is proposed to standardize 3D-profile measurement through reference metrology. In this article, we apply the methodology to line profile measurements and roughness measurement of advanced FinFET (Fin-shaped Field-Effect Transistor) features. The FinFET features are horizontally sliced as a thin specimen by FIB micro sampling system. Horizontally images of the specimens are obtained then by a planar TEM. LWR is calculated from the edges positions on TEM images. Moreover, we already have demonstrated the novel on-wafer 3D-profile metrology as "FIB-to-CDSEM method" with FIB slope cut and CD-SEM measuring. Using the method, a few micrometers wide on a wafer is coated and cut by 45-degree slope using FIB tool. Then, the wafer is transferred to CD-SEM to measure the cross section image by top down CD-SEM measurement. We applied FIB-to-CDSEM method to a CMOS image sensor feature. The 45-degree slope cut surface is observed using AFM. The surface profile of slope cut surface and line profiles are analyzed for improving the accuracy of FIB-to-CDSEM method.
Controlled enzymatic cutting of DNA molecules adsorbed on surfaces using soft lithography
NASA Astrophysics Data System (ADS)
Auerbach, Alyssa; Budassi, Julia; Shea, Emily; Zhu, Ke; Sokolov, Jonathan
2013-03-01
The enzyme DNase I was applied to adsorbed and aligned DNA molecules (Lamda, 48.5 kilobase pairs (kbp), and T4, 165.6 kbp), stretched linearly on a surface, by stamping with a polydimethylsiloxane (PDMS) grating. The DNAs were cut by the enzyme into separated, micron-sized segments along the length of the molecules at positions determined by the grating dimensions (3-20 microns). Ozone-treated PDMS stamps were coated with DNase I solutions and placed in contact with surface-adsorbed DNA molecules deposited on a 750 polymethylmethacrylate (PMMA) film spun-cast onto a silicon substrate. The stamps were applied under pressure for times up to 15 minutes at 37 C. The cutting was observed by fluorescence microscopy imaging of DNA labeled with YOYO dye. Cutting was found to be efficient despite the steric hindrance due to surface attachment of the molecules. Methods for detaching and separating the cut segments for sequencing applications will be discussed. Supported by NSF-DMR program.
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.
Conceptual Design Study on Bolts for Self-Loosing Preventable Threaded Fasteners
NASA Astrophysics Data System (ADS)
Noma, Atsushi; He, Jianmei
2017-11-01
Threaded fasteners using bolts is widely applied in industrial field as well as various fields. However, threaded fasteners using bolts have loosing problems and cause many accidents. In this study, the purpose is to obtain self-loosing preventable threaded fasteners by applying spring characteristic effects on bolt structures. Helical-cutting applied bolt structures is introduced through three dimensional (3D) CAD modeling tools. Analytical approaches for evaluations on the spring characteristic effects helical-cutting applied bolt structures and self-loosing preventable performance of threaded fasteners were performed using finite element method and results are reported. Comparing slackness test results with analytical results and more details on evaluating mechanical properties will be executed in future study.
Shaping of Rack Cutter Original Profile for Fine-module Ratchet Teeth Cutting
NASA Astrophysics Data System (ADS)
Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.
2018-05-01
The design models and the process of shaping the cutting edges of the rack cutter for cutting fine-module ratchet teeth are considered in the article. The use of fine-module ratchet teeth can reduce the noise and impact loads during operation of the freewheel mechanisms. Mathematical dependencies for calculating the coordinates determining the geometric position of the points of the front and back edges of the cutting profile of the rack cutter, the workpiece angle of rotation during cutting the ratchet teeth were obtained. When applying the developed method, the initial data are: the radii of the workpiece circumferences passing through the dedendum of the external and internal cut teeth; gradient angles of the front and back edges of the rail.
Microtunneling systems and methods of use
Richardson, John G.; Kostelnik, Kevin M.; Nickelson, Reva A.; Sloan, Paul A.
2006-07-04
A tunneling system including a tunneling apparatus including a cutting structure for forming a borehole and at least one linkage section for transmitting a force generally toward the cutting structure is disclosed. A method of disposing a casing string within a subterranean formation by applying a force generally to the trailing end of the tunneling apparatus, generally toward the leading end thereof, but without transmitting the entire force through the entire casing string is also disclosed. At least one linkage section extending within but not in contact with at least one casing section of the casing string may transmit the force. Also, a force limiting member may limit a force applied to the casing string.
Non-rigid image registration using graph-cuts.
Tang, Tommy W H; Chung, Albert C S
2007-01-01
Non-rigid image registration is an ill-posed yet challenging problem due to its supernormal high degree of freedoms and inherent requirement of smoothness. Graph-cuts method is a powerful combinatorial optimization tool which has been successfully applied into image segmentation and stereo matching. Under some specific constraints, graph-cuts method yields either a global minimum or a local minimum in a strong sense. Thus, it is interesting to see the effects of using graph-cuts in non-rigid image registration. In this paper, we formulate non-rigid image registration as a discrete labeling problem. Each pixel in the source image is assigned a displacement label (which is a vector) indicating which position in the floating image it is spatially corresponding to. A smoothness constraint based on first derivative is used to penalize sharp changes in displacement labels across pixels. The whole system can be optimized by using the graph-cuts method via alpha-expansions. We compare 2D and 3D registration results of our method with two state-of-the-art approaches. It is found that our method is more robust to different challenging non-rigid registration cases with higher registration accuracy.
An integrand reconstruction method for three-loop amplitudes
NASA Astrophysics Data System (ADS)
Badger, Simon; Frellesvig, Hjalte; Zhang, Yang
2012-08-01
We consider the maximal cut of a three-loop four point function with massless kinematics. By applying Gröbner bases and primary decomposition we develop a method which extracts all ten propagator master integral coefficients for an arbitrary triple-box configuration via generalized unitarity cuts. As an example we present analytic results for the three loop triple-box contribution to gluon-gluon scattering in Yang-Mills with adjoint fermions and scalars in terms of three master integrals.
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.
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
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
Effect of ethanol treatment on physiological and quality attributes of fresh-cut eggplant.
Hu, Wenzhong; Jiang, Aili; Tian, Mixia; Liu, Chenghui; Wang, Yanying
2010-06-01
Fresh-cut eggplants, as other vegetables, have relatively short shelf life because of the large amount of tissue disruption and increased metabolism. There is a very rapid onset of enzymatic browning and tissue softening with consequent decrease in sensorial and nutritional quality. To reduce respiration and maintain the quality, various treatments have been applied to find the optimum conditions that provide more fresh and natural fresh-cut produce after minimal processing. The objective of this study was to investigate the effects of ethanol vapour treatment on physiological and quality attributes of fresh-cut eggplant during the extension of shelf life. The fresh-cut eggplant treated with ethanol vapour showed that respiration rate and occurrence of enzymatic browning were reduced, and higher total phenol content was maintained during 8 days of storage at 10 degrees C. The polyphenol oxidase and peroxidase in fresh-cut eggplant were also inhibited significantly by ethanol treatment. The ethanol treatment reduced the weight loss and maintained the integrity of cell membranes, as confirmed by the low value of electrolyte leakage. The ethanol treatment applied for fresh-cut eggplant was a practical approach to reduce the activity of physiological metabolism and maintain the fresh quality of fresh-cut eggplant. The experimental results revealed that ethanol treatment was effective for extending the shelf life of fresh-cut eggplant as a cheap, environmentally acceptable method. Copyright (c) 2010 Society of Chemical Industry.
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.
Yang, Wai Yew; Burrows, Tracy; Collins, Clare E; MacDonald-Wicks, Lesley; Williams, Lauren T; Chee, Winnie Siew Swee
2014-12-01
This study aimed to identify the prevalence of energy misreporting amongst a sample of Malay children aged 9-11 years (n = 14) using a range of commonly used cut points. Participants were interviewed using repeated 24 h dietary recalls over three occasions. The Goldberg equations (1991 and 2000), Torun cut points and the Black and Cole method were applied to the data. Up to 11 of 14 children were classified as misreporters, with more under-reporters (between seven and eight children) than over-reporters (four or less children). There were significant differences in the proportion of children classified as energy misreporters when applying basal metabolic rate calculated using FAO/UNU/WHO (1985) and Malaysian-specific equations (p < 0.05). The results show that energy misreporting is common amongst Malay children, varying according to cut point chosen. Objective evaluation of total energy expenditure would help identify which cut point is appropriate for use in Malay paediatric populations. © The Author [2014]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Kim, N H; Lee, N Y; Kim, S H; Lee, H J; Kim, Y; Ryu, J H; Rhee, M S
2015-07-01
To develop a mild blanching method with calcium salts to ensure microbiological safety and quality of fresh-cut spinach. The antimicrobial efficacy of eight calcium salts was evaluated on Escherichia coli O157:H7 at 45-65°C and calcium hydroxide (Ca(OH)2 ) showed the greatest synergistic antimicrobial effect with heat. Combinations of low temperature treatments (45, 55, 65°C), time (20, 40, 60 s) and Ca(OH)2 (0·25, 0·50, 0·75%) were applied for E. coli O157:H7 disinfection on fresh-cut spinach to develop a predictive model using a Box-Behnken experimental design. A suitable quadratic model was produced (R(2) = 0·98, P < 0·001) and the optimum condition (64·9°C with 0·52% Ca(OH)2 for 42·4 s) was drawn by reducing 6·6 log CFU g(-1) of E. coli O157:H7 on fresh-cut spinach. Blanching at 61·9°C with 0·52% Ca(OH)2 for 41·7 s can inactivate E. coli O157:H7 on spinach by 5·4 log CFU g(-1) . The new method was comparable to the CDC recommendation for safe spinach cooking (71·1°C, 15 s; 5·0 log CFU g(-1) reduction) with lower levels of weight loss of the spinach (P < 0·05). This study suggests an efficient spinach blanching method for E. coli O157:H7 disinfection. This blanching method will enhance microbiological safety of fresh-cut produce while minimizing the use of energy and chemicals. © 2015 The Society for Applied Microbiology.
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
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.
Browning control of fresh-cut lettuce by phytoncide treatment.
Kim, Do-Hee; Kim, Han-Bit; Chung, Hun-Sik; Moon, Kwang-Deog
2014-09-15
Phytoncide essential oil derived from pine leaves was applied for the control of enzymatic browning of fresh-cut lettuce. Changes in the browning characteristics of cut lettuce treated with phytoncide in an water or ethanol solution (1%, v/v) at 10°C were investigated for 12days at 4°C. Other samples dipped in distilled water or 95% ethanol were used as the controls. The samples treated with phytoncide in an ethanol solution showed significantly higher L* values and lower a* values, ΔE values, browning index, phenolic compounds, and enzyme activities (PPO, POD, PAL) related to browning. The samples dipped in distilled water showed the opposite tendency. On the basis of changes in the browning characteristics, anti-browning effects of each treatment, phytoncide in an ethanol solution was the most effective treatment applied. These results suggest that phytoncide treatment could be used as an effective method for controlling enzymatic browning in fresh-cut lettuce. Copyright © 2014 Elsevier Ltd. All rights reserved.
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.
An Integrated Method Based on PSO and EDA for the Max-Cut Problem.
Lin, Geng; Guan, Jian
2016-01-01
The max-cut problem is NP-hard combinatorial optimization problem with many real world applications. In this paper, we propose an integrated method based on particle swarm optimization and estimation of distribution algorithm (PSO-EDA) for solving the max-cut problem. The integrated algorithm overcomes the shortcomings of particle swarm optimization and estimation of distribution algorithm. To enhance the performance of the PSO-EDA, a fast local search procedure is applied. In addition, a path relinking procedure is developed to intensify the search. To evaluate the performance of PSO-EDA, extensive experiments were carried out on two sets of benchmark instances with 800 to 20,000 vertices from the literature. Computational results and comparisons show that PSO-EDA significantly outperforms the existing PSO-based and EDA-based algorithms for the max-cut problem. Compared with other best performing algorithms, PSO-EDA is able to find very competitive results in terms of solution quality.
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.
Graph cuts via l1 norm minimization.
Bhusnurmath, Arvind; Taylor, Camillo J
2008-10-01
Graph cuts have become an increasingly important tool for solving a number of energy minimization problems in computer vision and other fields. In this paper, the graph cut problem is reformulated as an unconstrained l1 norm minimization that can be solved effectively using interior point methods. This reformulation exposes connections between the graph cuts and other related continuous optimization problems. Eventually the problem is reduced to solving a sequence of sparse linear systems involving the Laplacian of the underlying graph. The proposed procedure exploits the structure of these linear systems in a manner that is easily amenable to parallel implementations. Experimental results obtained by applying the procedure to graphs derived from image processing problems are provided.
Control of water erosion and sediment in open cut coal mines in tropical areas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ueda, T.; Nugraha, C.; Matsui, K.
2005-07-01
The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal measures under wet conditions, water management at pits and haul roads and ramps, and construction of waste dumps and water management. The results will be applied to the optimum control and management of erosion and sediments in open cut mining.more » 6 refs., 8 figs.« less
NASA Astrophysics Data System (ADS)
Mohruni, Amrifan Saladin; Yanis, Muhammad; Sharif, Safian; Yani, Irsyadi; Yuliwati, Erna; Ismail, Ahmad Fauzi; Shayfull, Zamree
2017-09-01
Thin-wall components as usually applied in the structural parts of aeronautical industry require significant challenges in machining. Unacceptable surface roughness can occur during machining of thin-wall. Titanium product such Ti6Al4V is mostly applied to get the appropriate surface texture in thin wall designed requirements. In this study, the comparison of the accuracy between Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) in the prediction of surface roughness was conducted. Furthermore, the machining tests were carried out under Minimum Quantity Lubrication (MQL) using AlCrN-coated carbide tools. The use of Coconut oil as cutting fluids was also chosen in order to evaluate its performance when involved in end milling. This selection of cutting fluids is based on the better performance of oxidative stability than that of other vegetable based cutting fluids. The cutting speed, feed rate, radial and axial depth of cut were used as independent variables, while surface roughness is evaluated as the dependent variable or output. The results showed that the feed rate is the most significant factors in increasing the surface roughness value followed by the radial depth of cut and lastly the axial depth of cut. In contrary, the surface becomes smoother with increasing the cutting speed. From a comparison of both methods, the ANN model delivered a better accuracy than the RSM model.
Photodiode-based cutting interruption sensor for near-infrared lasers.
Adelmann, B; Schleier, M; Neumeier, B; Hellmann, R
2016-03-01
We report on a photodiode-based sensor system to detect cutting interruptions during laser cutting with a fiber laser. An InGaAs diode records the thermal radiation from the process zone with a ring mirror and optical filter arrangement mounted between a collimation unit and a cutting head. The photodiode current is digitalized with a sample rate of 20 kHz and filtered with a Chebyshev Type I filter. From the measured signal during the piercing, a threshold value is calculated. When the diode signal exceeds this threshold during cutting, a cutting interruption is indicated. This method is applied to sensor signals from cutting mild steel, stainless steel, and aluminum, as well as different material thicknesses and also laser flame cutting, showing the possibility to detect cutting interruptions in a broad variety of applications. In a series of 83 incomplete cuts, every cutting interruption is successfully detected (alpha error of 0%), while no cutting interruption is reported in 266 complete cuts (beta error of 0%). With this remarkable high detection rate and low error rate, the possibility to work with different materials and thicknesses in combination with the easy mounting of the sensor unit also to existing cutting machines highlight the enormous potential for this sensor system in industrial applications.
Luo, W; Chen, M; Chen, A; Dong, W; Hou, X; Pu, B
2015-04-01
To isolate lactic acid bacteria (LAB) from pao cai, a Chinese traditional fermented vegetable, with outstanding inhibitory activity against Salmonella inoculated on fresh-cut apple, using a modelling method. Four kinds of pao cai were selected. A total of 122 isolates exhibited typical LAB characteristics: Gram-positive and catalase negative, among which 104 (85·24%) colonies showed antibacterial activity against Salmonella by the well diffusion assay. Four colonies showing maximum antibacterial radius against Salmonella were selected to co-inoculate with Salmonella on fresh-cut apple and stored at 10°C, further identified as three strains of Lactobacillus plantarum and one strain of Lactobacillus brevis by 16s rRNA gene sequence analysis. The modified Gompertz model was employed to analyse the growth of the micro-organisms on apple wedges. Two of the four selected strains showed antagonistic activity against Salmonella on fresh-cut apple, one of which, RD1, exhibited best inhibitory activity (Salmonella were greatly inhibited when co-inoculated with RD1 at 10°C at 168 h). No deterioration in odour or appearance of the apple piece was observed by the triangle test when fresh-cut apple was inoculated with RD1. The mathematical modelling method is essential to select LAB with outstanding inhibitory activity against Salmonella associated with fresh-cut apple. LAB RD1 holds promise for the preservation of fresh-cut apple. This study provided a new method on fresh-cut product preservation. Besides, to make the LAB isolating procedure a more correct one, this study first added the mathematical modelling method to the isolating procedure. © 2014 The Society for Applied Microbiology.
Identification of the traditional methods of newborn mothers regarding jaundice in Turkey.
Aydin, Diler; Karaca Ciftci, Esra; Karatas, Hulya
2014-02-01
To detect traditional methods applied for the treatment of newborn jaundice by mothers in Turkey. Traditional methods are generally used in our society. Instead of using medical services, people often use already-known traditional methods to treat the disease. In such cases, the prognosis of the disease generally becomes worse, the treatment period longer and healthcare costs higher, and more medicine is used. A cross-sectional descriptive study. The participants of this study were 229 mothers with newborn babies aged 0-28 days in one university hospital and one public children's hospital in Sanliurfa. The study was conducted between March and May 2012. In this research, the Beliefs and Traditional Methods of Mothers for Jaundice Questionnaire, which was formed by searching the relevant literature, is used as a data collection tool. The data are evaluated by percentage distributions. Mothers apply conventional practices in cases of health problems such as jaundice, and application of these methods is important to mothers. Moreover, mothers reported applying hazardous conventional methods in cases of neonatal jaundice, such as cutting the area between the baby's eyebrows with a blade, cutting the back of the ear and the body and burning the body, which are not applied in different cultures. Education regarding the effects of conventional methods being applied in families should be provided, and the results of this study should serve to guide further studies in assessing the effects of such education. This approach can support beneficial practices involving individual care and prevent the negative health effects of hazardous practices. © 2013 John Wiley & Sons Ltd.
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.
Source selection for cluster weak lensing measurements in the Hyper Suprime-Cam survey
NASA Astrophysics Data System (ADS)
Medezinski, Elinor; Oguri, Masamune; Nishizawa, Atsushi J.; Speagle, Joshua S.; Miyatake, Hironao; Umetsu, Keiichi; Leauthaud, Alexie; Murata, Ryoma; Mandelbaum, Rachel; Sifón, Cristóbal; Strauss, Michael A.; Huang, Song; Simet, Melanie; Okabe, Nobuhiro; Tanaka, Masayuki; Komiyama, Yutaka
2018-03-01
We present optimized source galaxy selection schemes for measuring cluster weak lensing (WL) mass profiles unaffected by cluster member dilution from the Subaru Hyper Suprime-Cam Strategic Survey Program (HSC-SSP). The ongoing HSC-SSP survey will uncover thousands of galaxy clusters to z ≲ 1.5. In deriving cluster masses via WL, a critical source of systematics is contamination and dilution of the lensing signal by cluster members, and by foreground galaxies whose photometric redshifts are biased. Using the first-year CAMIRA catalog of ˜900 clusters with richness larger than 20 found in ˜140 deg2 of HSC-SSP data, we devise and compare several source selection methods, including selection in color-color space (CC-cut), and selection of robust photometric redshifts by applying constraints on their cumulative probability distribution function (P-cut). We examine the dependence of the contamination on the chosen limits adopted for each method. Using the proper limits, these methods give mass profiles with minimal dilution in agreement with one another. We find that not adopting either the CC-cut or P-cut methods results in an underestimation of the total cluster mass (13% ± 4%) and the concentration of the profile (24% ± 11%). The level of cluster contamination can reach as high as ˜10% at R ≈ 0.24 Mpc/h for low-z clusters without cuts, while employing either the P-cut or CC-cut results in cluster contamination consistent with zero to within the 0.5% uncertainties. Our robust methods yield a ˜60 σ detection of the stacked CAMIRA surface mass density profile, with a mean mass of M200c = [1.67 ± 0.05(stat)] × 1014 M⊙/h.
Measurement of the residual stress in hot rolled strip using strain gauge method
NASA Astrophysics Data System (ADS)
Kumar, Lokendra; Majumdar, Shrabani; Sahu, Raj Kumar
2017-07-01
Measurement of the surface residual stress in a flat hot rolled steel strip using strain gauge method is considered in this paper. Residual stresses arise in the flat strips when the shear cut and laser cut is applied. Bending, twisting, central buckled and edge waviness is the common defects occur during the cutting and uncoiling process. These defects arise due to the non-uniform elastic-plastic deformation, phase transformation occurring during cooling and coiling-uncoiling process. The residual stress analysis is very important because with early detection it is possible to prevent an object from failure. The goal of this paper is to measure the surface residual stress in flat hot rolled strip using strain gauge method. The residual stress was measured in the head and tail end of hot rolled strip considering as a critical part of the strip.
Constraint Optimization Problem For The Cutting Of A Cobalt Chrome Refractory Material
NASA Astrophysics Data System (ADS)
Lebaal, Nadhir; Schlegel, Daniel; Folea, Milena
2011-05-01
This paper shows a complete approach to solve a given problem, from the experimentation to the optimization of different cutting parameters. In response to an industrial problem of slotting FSX 414, a Cobalt-based refractory material, we have implemented a design of experiment to determine the most influent parameters on the tool life, the surface roughness and the cutting forces. After theses trials, an optimization approach has been implemented to find the lowest manufacturing cost while respecting the roughness constraints and cutting force limitation constraints. The optimization approach is based on the Response Surface Method (RSM) using the Sequential Quadratic programming algorithm (SQP) for a constrained problem. To avoid a local optimum and to obtain an accurate solution at low cost, an efficient strategy, which allows improving the RSM accuracy in the vicinity of the global optimum, is presented. With these models and these trials, we could apply and compare our optimization methods in order to get the lowest cost for the best quality, i.e. a satisfying surface roughness and limited cutting forces.
Fractal characteristic in the wearing of cutting tool
NASA Astrophysics Data System (ADS)
Mei, Anhua; Wang, Jinghui
1995-11-01
This paper studies the cutting tool wear with fractal geometry. The wearing image of the flank has been collected by machine vision which consists of CCD camera and personal computer. After being processed by means of preserving smoothing, binary making and edge extracting, the clear boundary enclosing the worn area has been obtained. The fractal dimension of the worn surface is calculated by the methods called `Slit Island' and `Profile'. The experiments and calciating give the conclusion that the worn surface is enclosed by a irregular boundary curve with some fractal dimension and characteristics of self-similarity. Furthermore, the relation between the cutting velocity and the fractal dimension of the worn region has been submitted. This paper presents a series of methods for processing and analyzing the fractal information in the blank wear, which can be applied to research the projective relation between the fractal structure and the wear state, and establish the fractal model of the cutting tool wear.
Modeling the forces of cutting with scissors.
Mahvash, Mohsen; Voo, Liming M; Kim, Diana; Jeung, Kristin; Wainer, Joshua; Okamura, Allison M
2008-03-01
Modeling forces applied to scissors during cutting of biological materials is useful for surgical simulation. Previous approaches to haptic display of scissor cutting are based on recording and replaying measured data. This paper presents an analytical model based on the concepts of contact mechanics and fracture mechanics to calculate forces applied to scissors during cutting of a slab of material. The model considers the process of cutting as a sequence of deformation and fracture phases. During deformation phases, forces applied to the scissors are calculated from a torque-angle response model synthesized from measurement data multiplied by a ratio that depends on the position of the cutting crack edge and the curve of the blades. Using the principle of conservation of energy, the forces of fracture are related to the fracture toughness of the material and the geometry of the blades of the scissors. The forces applied to scissors generally include high-frequency fluctuations. We show that the analytical model accurately predicts the average applied force. The cutting model is computationally efficient, so it can be used for real-time computations such as haptic rendering. Experimental results from cutting samples of paper, plastic, cloth, and chicken skin confirm the model, and the model is rendered in a haptic virtual environment.
Pattern detection in forensic case data using graph theory: application to heroin cutting agents.
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.
Establishing even-age northern hardwood regeneration by the shelterwood method--a preliminary guide.
Richard M. Godman; Carl H. Tubbs
1973-01-01
The shelterwood system of regeneration with northern hardwoods is a reliable method of obtaining even-age stands of both tolerant and moderately tolerant species. Details of applying the two-cut system are described along with the necessary modifications for encouraging moderately tolerant species.
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.
Midstory hardwood species respond differently to chainsaw girdle method and herbicide treatment
Ronald A. Rathfon; Michael R. Saunders
2013-01-01
Foresters in the Central Hardwoods Region commonly fell or girdle interfering trees and apply herbicide to the cut surface when performing intermediate silvicultural treatments. The objective of this study was to compare the use of single and double chainsaw girdle methods in combination with a herbicide treatment and, within the double girdle method, compare herbicide...
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.
Xu, Jing; Wang, Zhongbin; Tan, Chao; Si, Lei; Liu, Xinhua
2015-01-01
In order to guarantee the stable operation of shearers and promote construction of an automatic coal mining working face, an online cutting pattern recognition method with high accuracy and speed based on Improved Ensemble Empirical Mode Decomposition (IEEMD) and Probabilistic Neural Network (PNN) is proposed. An industrial microphone is installed on the shearer and the cutting sound is collected as the recognition criterion to overcome the disadvantages of giant size, contact measurement and low identification rate of traditional detectors. To avoid end-point effects and get rid of undesirable intrinsic mode function (IMF) components in the initial signal, IEEMD is conducted on the sound. The end-point continuation based on the practical storage data is performed first to overcome the end-point effect. Next the average correlation coefficient, which is calculated by the correlation of the first IMF with others, is introduced to select essential IMFs. Then the energy and standard deviation of the reminder IMFs are extracted as features and PNN is applied to classify the cutting patterns. Finally, a simulation example, with an accuracy of 92.67%, and an industrial application prove the efficiency and correctness of the proposed method. PMID:26528985
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.
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.
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.
Muscle Fiber Orientation Angle Dependence of the Tensile Fracture Behavior of Frozen Fish Muscle
NASA Astrophysics Data System (ADS)
Hagura, Yoshio; Okamoto, Kiyoshi; Suzuki, Kanichi; Kubota, Kiyoshi
We have proposed a new cutting method for frozen fish named "cryo-cutting". This method applied tensile fracture force or bending fracture force to the frozen fish at appropriate low temperatures. In this paper, to clarify cryo-cutting mechanism, we analyzed tensile fracture behavior of the frozen fish muscle. In the analysis, the frozen fish muscle was considered unidirectionally fiber-reinforced composite material which consisted of fiber (muscle fiber) and matrix (connective tissue). Fracture criteria (maximum stress criterion, Tsai-Hill criterion) for the unidirectionally fiber-reinforced composite material were used. The following results were obtained: (1) By using Tsai-Hill criterion, muscle fiber orientation angle dependence of the tensile fracture stress could be calculated. (2) By using the maximum stress theory jointly with Tsai-Hill criterion, muscle fiber orientation angle dependence of the fracture mode of the frozen fish muscle could be estimated.
Slice-push, formation of grooves and the scale effect in cutting.
Atkins, A G
2016-06-06
Three separate aspects of cutting are investigated which complement other papers on the mechanics of separation processes presented at this interdisciplinary Theo Murphy meeting. They apply in all types of cutting whether blades are sharp or blunt, and whether the material being cut is 'hard, stiff and strong' or 'soft, compliant and weak'. The first topic discusses why it is easier to cut when there is motion along (parallel to) the blade as well motion across (perpendicular to) the cutting edge, and the analysis is applied to optimization of blade geometries to produce minimum cutting forces and hence minimum damage to cut surfaces. The second topic concerns cutting with more than one edge with particular application to the formation of grooves in surfaces by hard pointed tools. The mechanics are investigated and applied to the topic of abrasive wear by hard particles. Traditional analyses say that abrasive wear resistance increases monotonically with the hardness of the workpiece, but we show that the fracture toughness of the surface material is also important, and that behaviour is determined by the toughness-to-hardness ratio rather than hardness alone. Scaling forms the third subject. As cutting is a branch of elasto-plastic fracture mechanics, cube-square energy scaling applies in which the important length scale is (ER/k (2)), where E is Young's modulus, R is the fracture toughness and k is the shear yield strength. Whether, in cutting, material is removed as ductile ribbons, as semi-ductile discontinuous chips, or by brittle 'knocking lumps out' is shown to depend on the depth of cut relative to this characteristic length parameter. Scaling in biology is called allometry and its relationship with engineering scaling is discussed. Some speculative predictions are made in relation to the action of teeth on food.
Method and apparatus for preventing cyclotron breakdown in partially evacuated waveguide
Moeller, Charles P.
1987-01-01
Cyclotron breakdown is prevented in a partially evacuated waveguide by providing a section of waveguide having an axial cut therein in order to apply a potential across the two halves of the waveguide. This section is positioned in the waveguide crossing the area of electron cyclotron resonance. The potential applied across the waveguide halves is used to deflect seed electrons into the wall of the waveguide in order to prevent ionization of gas molecules and creation of more electron ion pairs which would result in cyclotron breakdown. Support means is also disclosed for electrically isolating the waveguide halves and transition means is provided between the section of the waveguide with the axial cut and the solid waveguide at either end thereof.
NASA Technical Reports Server (NTRS)
Roth, Don J.; Farmer, Donald A.
1998-01-01
Abrasive cut-off wheels are at times unintentionally manufactured with nonuniformity that is difficult to identify and sufficiently characterize without time-consuming, destructive examination. One particular nonuniformity is a density variation condition occurring around the wheel circumference or along the radius, or both. This density variation, depending on its severity, can cause wheel warpage and wheel vibration resulting in unacceptable performance and perhaps premature failure of the wheel. Conventional nondestructive evaluation methods such as ultrasonic c-scan imaging and film radiography are inaccurate in their attempts at characterizing the density variation because a superimposing thickness variation exists as well in the wheel. In this article, the single transducer thickness-independent ultrasonic imaging method, developed specifically to allow more accurate characterization of aerospace components, is shown to precisely characterize the extent of the density variation in a cut-off wheel having a superimposing thickness variation. The method thereby has potential as an effective quality control tool in the abrasives industry for the wheel manufacturer.
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
Thermal modelling of cooling tool cutting when milling by electrical analogy
NASA Astrophysics Data System (ADS)
Benabid, F.; Arrouf, M.; Assas, M.; Benmoussa, H.
2010-06-01
Measurement temperatures by (some devises) are applied immediately after shut-down and may be corrected for the temperature drop that occurs in the interval between shut-down and measurement. This paper presents a new procedure for thermal modelling of the tool cutting used just after machining; when the tool is out off the chip in order to extrapolate the cutting temperature from the temperature measured when the tool is at stand still. A fin approximation is made in enhancing heat loss (by conduction and convection) to air stream is used. In the modelling we introduce an equivalent thermal network to estimate the cutting temperature as a function of specific energy. In another hand, a local modified element lumped conduction equation is used to predict the temperature gradient with time when the tool is being cooled, with initial and boundary conditions. These predictions provide a detailed view of the global heat transfer coefficient as a function of cutting speed because the heat loss for the tool in air stream is an order of magnitude larger than in normal environment. Finally we deduct the cutting temperature by inverse method.
Numerical modelling of orthogonal cutting: application to woodworking with a bench plane.
Nairn, John A
2016-06-06
A numerical model for orthogonal cutting using the material point method was applied to woodcutting using a bench plane. The cutting process was modelled by accounting for surface energy associated with wood fracture toughness for crack growth parallel to the grain. By using damping to deal with dynamic crack propagation and modelling all contact between wood and the plane, simulations could initiate chip formation and proceed into steady-state chip propagation including chip curling. Once steady-state conditions were achieved, the cutting forces became constant and could be determined as a function of various simulation variables. The modelling details included a cutting tool, the tool's rake and grinding angles, a chip breaker, a base plate and a mouth opening between the base plate and the tool. The wood was modelled as an anisotropic elastic-plastic material. The simulations were verified by comparison to an analytical model and then used to conduct virtual experiments on wood planing. The virtual experiments showed interactions between depth of cut, chip breaker location and mouth opening. Additional simulations investigated the role of tool grinding angle, tool sharpness and friction.
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.
He, Pei
2014-07-01
The advancements in biotechnology and genetics lead to an increasing research interest in personalized medicine, where a patient's genetic profile or biological traits contribute to choosing the most effective treatment for the patient. The process starts with finding a specific biomarker among all possible candidates that can best predict the treatment effect. After a biomarker is chosen, identifying a cut point of the biomarker value that splits the patients into treatment effective and non-effective subgroups becomes an important scientific problem. Numerous methods have been proposed to validate the predictive marker and select the appropriate cut points either prospectively or retrospectively using clinical trial data. In trials with survival outcomes, the current practice applies an interaction testing procedure and chooses the cut point that minimizes the p-values for the tests. Such method assumes independence between the baseline hazard and biomarker value. In reality, however, this assumption is often violated, as the chosen biomarker might also be prognostic in addition to its predictive nature for treatment effect. In this paper we propose a block-wise estimation and a sequential testing approach to identify the cut point in biomarkers that can group the patients into subsets based on their distinct treatment outcomes without assuming independence between the biomarker and baseline hazard. Numerical results based on simulated survival data show that the proposed method could pinpoint accurately the cut points in biomarker values that separate the patient subpopulations into subgroups with distinctive treatment outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Almukhametova, E. M.; Gizetdinov, I. A.
2018-05-01
Development of most deposits in Russia is accompanied with a high level of crude water cut. More than 70% of the operating well count of Barsukovskoye deposit operates with water; about 12% of the wells are characterized by a saturated water cut; many wells with high water cut are idling. To optimize the current FPM system of the Barsukovskoye deposit, a calculation method over a hydrodynamic model was applied with further analysis of hydrodynamic connectivity between the wells. A plot was selected, containing several wells with water cut going ahead of reserve recovery rate; injection wells, exerting the most influence onto the selected producer wells, were determined. Then, several variants were considered for transformation of the FPM system of this plot. The possible cases were analyzed with the hydrodynamic model with further determination of economic effect of each of them.
Photonic mesophases from cut rod rotators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stelson, Angela C.; Liddell Watson, Chekesha M., E-mail: cml66@cornell.edu; Avendano, Carlos
2016-01-14
The photonic band properties of random rotator mesophases are calculated using supercell methods applied to cut rods on a hexagonal lattice. Inspired by the thermodynamic mesophase for anisotropic building blocks, we vary the shape factor of cut fraction for the randomly oriented basis. We find large, stable bandgaps with high gap isotropy in the inverted and direct structures as a function of cut fraction, dielectric contrast, and filling fraction. Bandgap sizes up to 34.5% are maximized at high dielectric contrast for rods separated in a matrix. The bandgaps open at dielectric contrasts as low as 2.0 for the transverse magneticmore » polarization and 2.25 for the transverse electric polarization. Additionally, the type of scattering that promotes the bandgap is correlated with the effect of disorder on bandgap size. Slow light properties are investigated in waveguide geometry and slowdown factors up to 5 × 10{sup 4} are found.« less
A new IRT-based standard setting method: application to eCat-listening.
García, Pablo Eduardo; Abad, Francisco José; Olea, Julio; Aguado, David
2013-01-01
Criterion-referenced interpretations of tests are highly necessary, which usually involves the difficult task of establishing cut scores. Contrasting with other Item Response Theory (IRT)-based standard setting methods, a non-judgmental approach is proposed in this study, in which Item Characteristic Curve (ICC) transformations lead to the final cut scores. eCat-Listening, a computerized adaptive test for the evaluation of English Listening, was administered to 1,576 participants, and the proposed standard setting method was applied to classify them into the performance standards of the Common European Framework of Reference for Languages (CEFR). The results showed a classification closely related to relevant external measures of the English language domain, according to the CEFR. It is concluded that the proposed method is a practical and valid standard setting alternative for IRT-based tests interpretations.
Girdling and Applying Chemicals Promote Rapid Rooting of Sycamore Cuttings
Robert C. Hare
1975-01-01
Shoots of 6- and 13-year-old sycamore (Platanus occidentalis L.) were girdled and treated with rooting powder 4 weeks before cuttings were taken. The powder, which contained auxins, sucrose, and cap tan, was also applied basally to nongirdled cuttings immediately before iwertion in a rooting medium. Thirteen days later, 100 percent of the...
Deferment cutting in central Appalachian hardwoods: an update
Gary w. Miller; James E. Johnson; John E. Baumgras
1997-01-01
This paper summarizes research results on deferment cutting, a silvicultural practice that promotes a two-age stand structure, as it has been applied in central Appalachian hardwoods on the Monongahela National Forest (MNF) since 1979. Ten-year results from experimental cuts that were applied from 1979 to 1983 indicated that 89% of residual trees survived, 76 to 100%...
Dental cutting behaviour of mica-based and apatite-based machinable glass-ceramics.
Taira, M; Wakasa, K; Yamaki, M; Matsui, A
1990-09-01
Some recently developed industrial ceramics have excellent machinability properties. The objective of this study was to evaluate the dental cutting behaviour of two machinable glass-ceramics, mica-containing Macor-M and apatite- and diopside-containing Bioram-M, and to compare them with the cutting behaviour of a composite resin typodont tooth enamel and bovine enamel. Weight-load cutting tests were conducted, using a diamond point driven by an air-turbine handpiece, While the transverse load applied on the point was varied, the handpiece speed during cutting and the volume of removal upon cutting were measured. In general, an increase in the applied load caused a decrease in cutting speed and an increase in cutting volume. However, the intensity of this trend was found to differ between four workpieces. Cutting Macor-M resulted in the second-most reduced cutting speed and the maximum cutting volume. Cutting Bioram-M gave the least reduced cutting speed and the minimum cutting volume. It was suggested that two machinable glass-ceramics could be employed as typodont teeth. This study may also contribute to the development of new restorative dental ceramic materials, prepared by machining.
An Interactive Image Segmentation Method in Hand Gesture Recognition
Chen, Disi; Li, Gongfa; Sun, Ying; Kong, Jianyi; Jiang, Guozhang; Tang, Heng; Ju, Zhaojie; Yu, Hui; Liu, Honghai
2017-01-01
In order to improve the recognition rate of hand gestures a new interactive image segmentation method for hand gesture recognition is presented, and popular methods, e.g., Graph cut, Random walker, Interactive image segmentation using geodesic star convexity, are studied in this article. The Gaussian Mixture Model was employed for image modelling and the iteration of Expectation Maximum algorithm learns the parameters of Gaussian Mixture Model. We apply a Gibbs random field to the image segmentation and minimize the Gibbs Energy using Min-cut theorem to find the optimal segmentation. The segmentation result of our method is tested on an image dataset and compared with other methods by estimating the region accuracy and boundary accuracy. Finally five kinds of hand gestures in different backgrounds are tested on our experimental platform, and the sparse representation algorithm is used, proving that the segmentation of hand gesture images helps to improve the recognition accuracy. PMID:28134818
Hanson, Erik A; Lundervold, Arvid
2013-11-01
Multispectral, multichannel, or time series image segmentation is important for image analysis in a wide range of applications. Regularization of the segmentation is commonly performed using local image information causing the segmented image to be locally smooth or piecewise constant. A new spatial regularization method, incorporating non-local information, was developed and tested. Our spatial regularization method applies to feature space classification in multichannel images such as color images and MR image sequences. The spatial regularization involves local edge properties, region boundary minimization, as well as non-local similarities. The method is implemented in a discrete graph-cut setting allowing fast computations. The method was tested on multidimensional MRI recordings from human kidney and brain in addition to simulated MRI volumes. The proposed method successfully segment regions with both smooth and complex non-smooth shapes with a minimum of user interaction.
Nucleon-nucleon interactions from dispersion relations: Elastic partial waves
NASA Astrophysics Data System (ADS)
Albaladejo, M.; Oller, J. A.
2011-11-01
We consider nucleon-nucleon (NN) interactions from chiral effective field theory. In this work we restrict ourselves to the elastic NN scattering. We apply the N/D method to calculate the NN partial waves taking as input the one-pion exchange discontinuity along the left-hand cut. This discontinuity is amenable to a chiral power counting as discussed by Lacour, Oller, and Meißner [Ann. Phys. (NY)APNYA60003-491610.1016/j.aop.2010.06.012 326, 241 (2011)], with one-pion exchange as its leading order contribution. The resulting linear integral equation for a partial wave with orbital angular momentum ℓ≥2 is solved in the presence of ℓ-1 constraints, so as to guarantee the right behavior of the D- and higher partial waves near threshold. The calculated NN partial waves are based on dispersion relations and are independent of regulator. This method can also be applied to higher orders in the calculation of the discontinuity along the left-hand cut and extended to triplet coupled partial waves.
Comparative study of 0° X-cut and Y + 36°-cut lithium niobate high-voltage sensing
NASA Astrophysics Data System (ADS)
Patel, N.; Branch, D. W.; Schamiloglu, E.; Cular, S.
2015-08-01
A comparison study between Y + 36° and 0° X-cut lithium niobate (LiNbO3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz-100 kHz. Using the same conditions as the Y + 36° cut, the 0° X-cut crystal sensed a shift of 10-273 ps for DC voltages and 189-813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250-2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115-1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.
Comparative study of 0° X-cut and Y + 36°-cut lithium niobate high-voltage sensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patel, N.; Department of Electrical and Computer Engineering, MSC01 1100, University of New Mexico, Albuquerque, New Mexico 87131-0001; Branch, D. W.
2015-08-15
A comparison study between Y + 36° and 0° X-cut lithium niobate (LiNbO{sub 3}) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y + 36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5more » μs voltage pulses to both crystals, the voltage-induced shift scaled linearly with voltage. For the Y + 36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz–100 kHz. Using the same conditions as the Y + 36° cut, the 0° X-cut crystal sensed a shift of 10–273 ps for DC voltages and 189–813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250–2 ns and the Y + 36°-cut crystal sensed a time shift of 0.115–1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. When the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.« less
Comparative study of 0° X-cut and Y+36°-cut lithium niobate high-voltage sensing
Patel, N.; Branch, D. W.; Schamiloglu, E.; ...
2015-08-11
A comparison study between Y+36° and 0° X-cut lithium niobate (LiNbO 3) was performed to evaluate the influence of crystal cut on the acoustic propagation to realize a piezoelectric high-voltage sensor. The acoustic time-of-flight for each crystal cut was measured when applying direct current (DC), alternating current (AC), and pulsed voltages. Results show that the voltage-induced shift in the acoustic wave propagation time scaled quadratically with voltage for DC and AC voltages applied to X-cut crystals. For the Y+36° crystal, the voltage-induced shift scales linearly with DC voltages and quadratically with AC voltages. When applying 5 μs voltage pulses tomore » both crystals, the voltage-induced shift scaled linearly with voltage. For the Y+36° cut, the voltage-induced shift from applying DC voltages ranged from 10 to 54 ps and 35 to 778 ps for AC voltages at 640 V over the frequency range of 100 Hz–100 kHz. Using the same conditions as the Y+36° cut, the 0° X-cut crystal sensed a shift of 10–273 ps for DC voltages and 189–813 ps for AC voltage application. For 5 μs voltage pulses, the 0° X-cut crystal sensed a voltage induced shift of 0.250–2 ns and the Y+36°-cut crystal sensed a time shift of 0.115–1.6 ns. This suggests a frequency sensitive response to voltage where the influence of the crystal cut was not a significant contributor under DC, AC, or pulsed voltage conditions. The measured DC data were compared to a 1-D impedance matrix model where the predicted incremental length changed as a function of voltage. Furthermore, when the voltage source error was eliminated through physical modeling from the uncertainty budget, the combined uncertainty of the sensor (within a 95% confidence interval) decreased to 0.0033% using a Y + 36°-cut crystal and 0.0032% using an X-cut crystal for all the voltage conditions used in this experiment.« less
Controlling beech root and stump sprouts using the cut-stump treatment
Jeffery D. Kochenderfer; James N. Kochenderfer; Gary W. Miller
2006-01-01
Application costs and efficacy were determined for cut-stump treatments applied to American beech (Fagus grandifolia Ehrh.) to control root and stump sprouts in central West Virginia. Glyphosate as Glypro (53.8%) was applied to the outer 2 in. of beech stumps from trees >6.0-in. dbh within 1 hour after cutting. In addition to treatment plots,...
NASA Astrophysics Data System (ADS)
Kroonblawd, Matthew P.; Mathew, Nithin; Jiang, Shan; Sewell, Thomas D.
2016-10-01
A Generalized Crystal-Cutting Method (GCCM) is developed that automates construction of three-dimensionally periodic simulation cells containing arbitrarily oriented single crystals and thin films, two-dimensionally (2D) infinite crystal-crystal homophase and heterophase interfaces, and nanostructures with intrinsic N-fold interfaces. The GCCM is based on a simple mathematical formalism that facilitates easy definition of constraints on cut crystal geometries. The method preserves the translational symmetry of all Bravais lattices and thus can be applied to any crystal described by such a lattice including complicated, low-symmetry molecular crystals. Implementations are presented with carefully articulated combinations of loop searches and constraints that drastically reduce computational complexity compared to simple loop searches. Orthorhombic representations of monoclinic and triclinic crystals found using the GCCM overcome some limitations in standard distributions of popular molecular dynamics software packages. Stability of grain boundaries in β-HMX was investigated using molecular dynamics and molecular statics simulations with 2D infinite crystal-crystal homophase interfaces created using the GCCM. The order of stabilities for the four grain boundaries studied is predicted to correlate with the relative prominence of particular crystal faces in lab-grown β-HMX crystals. We demonstrate how nanostructures can be constructed through simple constraints applied in the GCCM framework. Example GCCM constructions are shown that are relevant to some current problems in materials science, including shock sensitivity of explosives, layered electronic devices, and pharmaceuticals.
Strengthening method of concrete structure
NASA Astrophysics Data System (ADS)
Inge, Wewin; Audrey; Nugroho, Sofie; Njo, Helen
2018-03-01
Building extension in Indonesia is not favored, and not many people know the advantages of the method because architects and engineers tend to lack the knowledge and experience. The aim of this paper is to explain a method on how to strengthen a concrete building structure that people can use/learn as a better way to cut potential cost and save time. The strengthening method explained in this paper is steel jacketing, providing a case study of this method in the extension of a restaurant located in Medan, Indonesia. In this study, engineers calculated that the tensile stress of the existing RC column and beam is not strong enough to reinforce the building extension applied load. Therefore, the steel jacketing method can be applied to improve the column and beam strength and ductility. The result of the case study proves that this is one of the best methods for building extension applied in Indonesia.
Electromagnetic variable degrees of freedom actuator systems and methods
Montesanti, Richard C [Pleasanton, CA; Trumper, David L [Plaistow, NH; Kirtley, Jr., James L.
2009-02-17
The present invention provides a variable reluctance actuator system and method that can be adapted for simultaneous rotation and translation of a moving element by applying a normal-direction magnetic flux on the moving element. In a beneficial example arrangement, the moving element includes a swing arm that carries a cutting tool at a set radius from an axis of rotation so as to produce a rotary fast tool servo that provides a tool motion in a direction substantially parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. An actuator rotates a swing arm such that a cutting tool moves toward and away from a mounted rotating workpiece in a controlled manner in order to machine the workpiece. Position sensors provide rotation and displacement information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in feed slide of a precision lathe.
Real-time simulation of contact and cutting of heterogeneous soft-tissues.
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.
Mechanisms and FEM Simulation of Chip Formation in Orthogonal Cutting In-Situ TiB₂/7050Al MMC.
Xiong, Yifeng; Wang, Wenhu; Jiang, Ruisong; Lin, Kunyang; Shao, Mingwei
2018-04-15
The in-situ TiB₂/7050Al composite is a new kind of Al-based metal matrix composite (MMC) with super properties, such as low density, improved strength, and wear resistance. This paper, for a deep insight into its cutting performance, involves a study of the chip formation process and finite element simulation during orthogonal cutting in-situ TiB₂/7050Al MMC. With chips, material properties, cutting forces, and tool geometry parameters, the Johnson-Cook (J-C) constitutive equation of in-situ TiB₂/7050Al composite was established. Then, the cutting simulation model was established by applying the Abaqus-Explicit method, and the serrated chip, shear plane, strain rate, and temperature were analyzed. The experimental and simulation results showed that the obtained material's constitutive equation was of high reliability, and the saw-tooth chips occurred commonly under either low or high cutting speed and small or large feed rate. From result analysis, it was found that the mechanisms of chip formation included plastic deformation, adiabatic shear, shearing slip, and crack extension. In addition, it was found that the existence of small, hard particles reduced the ductility of the MMC and resulted in segmental chips.
Wanyenya, Irene; Muyanja, Charles; Nasinyama, George William
2004-09-01
Cross-contamination during food preparation has been identified as an important factor associated with foodborne illnesses. Handling practices used during preparation of broiler chickens in 31 fast-food restaurants and 86 semisettled street stands (street vendors) were assessed by use of a standard checklist. These establishments used wood, plastic, or metal cutting surfaces during the preparation of broiler chickens. The survival of Campylobacter spp. on kitchen cutting surfaces was determined by inoculating approximately 10(6) CFU of Campylobacter jejuni onto sterile plastic, wooden, and metal cutting boards. The concentrations of the organisms were then assessed in triplicate on each type of cutting board over a 3-h period using standard microbiological methods for thermophilic Campylobacter spp. In 87% of food establishments, the same work area was used for preparation of raw and cooked chicken, and in 68% of these establishments the same cutting boards were used for raw and cooked chicken. None of the establishments applied disinfectants or sanitizers when washing contact surfaces. Campylobacter spp. survived on wooden and plastic but not on metal cutting boards after 3 h of exposure. The handling practices in food preparation areas, therefore, provide an opportunity for cross-contamination of Campylobacter spp. to ready-to-eat foods.
29 CFR 1915.53 - Welding, cutting and heating in way of preservative coatings.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 7 2010-07-01 2010-07-01 false Welding, cutting and heating in way of preservative... SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.53 Welding, cutting and heating in way of... and shipbulding and shall not apply to shipbreaking. (b) Before welding, cutting or heating is...
29 CFR 1915.53 - Welding, cutting and heating in way of preservative coatings.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 7 2014-07-01 2014-07-01 false Welding, cutting and heating in way of preservative... SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.53 Welding, cutting and heating in way of... and shipbulding and shall not apply to shipbreaking. (b) Before welding, cutting or heating is...
29 CFR 1915.53 - Welding, cutting and heating in way of preservative coatings.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 7 2012-07-01 2012-07-01 false Welding, cutting and heating in way of preservative... SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.53 Welding, cutting and heating in way of... and shipbulding and shall not apply to shipbreaking. (b) Before welding, cutting or heating is...
29 CFR 1915.53 - Welding, cutting and heating in way of preservative coatings.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 7 2013-07-01 2013-07-01 false Welding, cutting and heating in way of preservative... SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.53 Welding, cutting and heating in way of... and shipbulding and shall not apply to shipbreaking. (b) Before welding, cutting or heating is...
29 CFR 1915.53 - Welding, cutting and heating in way of preservative coatings.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 7 2011-07-01 2011-07-01 false Welding, cutting and heating in way of preservative... SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.53 Welding, cutting and heating in way of... and shipbulding and shall not apply to shipbreaking. (b) Before welding, cutting or heating is...
Hoofs, H.; Jansen, N. W. H.; Mohren, D. C. L.; Jansen, M. W. J.; Kant, I. J.
2015-01-01
Background The Strength and Difficulties Questionnaire (SDQ) is a screening instrument for psychosocial problems in children and adolescents, which is applied in “individual” and “collective” settings. Assessment in the individual setting is confidential for clinical applications, such as preventive child healthcare, while assessment in the collective setting is anonymous and applied in (epidemiological) research. Due to administration differences between the settings it remains unclear whether results and conclusions actually can be used interchangeably. This study therefore aims to investigate whether the SDQ is invariant across settings. Methods Two independent samples were retrieved (mean age = 14.07 years), one from an individual setting (N = 6,594) and one from a collective setting (N = 4,613). The SDQ was administered in the second year of secondary school in both settings. Samples come from the same socio-geographic population in the Netherlands. Results Confirmatory factor analysis showed that the SDQ was measurement invariant/equivalent across settings and gender. On average, children in the individual setting scored lower on total difficulties (mean difference = 2.05) and the psychosocial problems subscales compared to those in the collective setting. This was also reflected in the cut-off points for caseness, defined by the 90th percentiles, which were lower in the individual setting. Using cut-off points from the collective in the individual setting therefore resulted in a small number of cases, 2 to 3%, while ∼10% is expected. Conclusion The SDQ has the same connotation across the individual and collective setting. The observed structural differences regarding the mean scores, however, undermine the validity of the cross-use of absolute SDQ-scores between these settings. Applying cut-off scores from the collective setting in the individual setting could, therefore, result in invalid conclusions and potential misuse of the instrument. To correctly apply cut-off scores these should be retrieved from the applied setting. PMID:25886464
A micro-scale cutting model for UD CFRP composites with thermo-mechanical coupling
Cheng, Hui; Gao, Jiaying; Kafka, Orion Landauer; ...
2017-09-23
Cutting a unidirectional carbon fiber-reinforced polymer (UD CFRP) structure is the basic unit for CFRP machining, which is a complex thermal-mechanically coupled process. To reveal the deformation mechanism and predict cutting force in UD CFRP micro cutting, a micro-scale fracture model for UD CFRP cutting with thermal-mechanical coupling is demonstrated in this paper, which captures the failure modes for fibers, matrix and the interface based on a micro-level RVE using a relatively simple damage based fracture method. The thermal-mechanical coupling model at the micro scale is developed on the basis of the plastic energy dissipation and frictional heating during cutting.more » Failure models for the fiber, matrix and interface region are applied depending on the material properties of each of these three phases. Numerical simulations based on the above model with different fiber orientations were performed to predict the deformation and forces of different components in UD CFRP. Cutting experiments with the same fiber orientations as considered in the simulations were carried out to validate the force and deformation results. The predicted force and deformation patterns match well with evidence from our experiments. In general, the cutting force is larger than the thrust force regardless of fiber orientation. The cutting force reaches a maximum as the fiber orientation approaches 90 , but thrust forces do not vary substantially across cases. When the fiber orientation is acute, the deformation of fibers is much smaller than when the cutting angle is obtuse. Surface roughness follows the same trend with cutting angle as fiber deformation.« less
A micro-scale cutting model for UD CFRP composites with thermo-mechanical coupling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng, Hui; Gao, Jiaying; Kafka, Orion Landauer
Cutting a unidirectional carbon fiber-reinforced polymer (UD CFRP) structure is the basic unit for CFRP machining, which is a complex thermal-mechanically coupled process. To reveal the deformation mechanism and predict cutting force in UD CFRP micro cutting, a micro-scale fracture model for UD CFRP cutting with thermal-mechanical coupling is demonstrated in this paper, which captures the failure modes for fibers, matrix and the interface based on a micro-level RVE using a relatively simple damage based fracture method. The thermal-mechanical coupling model at the micro scale is developed on the basis of the plastic energy dissipation and frictional heating during cutting.more » Failure models for the fiber, matrix and interface region are applied depending on the material properties of each of these three phases. Numerical simulations based on the above model with different fiber orientations were performed to predict the deformation and forces of different components in UD CFRP. Cutting experiments with the same fiber orientations as considered in the simulations were carried out to validate the force and deformation results. The predicted force and deformation patterns match well with evidence from our experiments. In general, the cutting force is larger than the thrust force regardless of fiber orientation. The cutting force reaches a maximum as the fiber orientation approaches 90 , but thrust forces do not vary substantially across cases. When the fiber orientation is acute, the deformation of fibers is much smaller than when the cutting angle is obtuse. Surface roughness follows the same trend with cutting angle as fiber deformation.« less
NASA Astrophysics Data System (ADS)
Adesta, Erry Yulian T.; Riza, Muhammad; Avicena
2018-03-01
Tool wear prediction plays a significant role in machining industry for proper planning and control machining parameters and optimization of cutting conditions. This paper aims to investigate the effect of tool path strategies that are contour-in and zigzag tool path strategies applied on tool wear during pocket milling process. The experiments were carried out on CNC vertical machining centre by involving PVD coated carbide inserts. Cutting speed, feed rate and depth of cut were set to vary. In an experiment with three factors at three levels, Response Surface Method (RSM) design of experiment with a standard called Central Composite Design (CCD) was employed. Results obtained indicate that tool wear increases significantly at higher range of feed per tooth compared to cutting speed and depth of cut. This result of this experimental work is then proven statistically by developing empirical model. The prediction model for the response variable of tool wear for contour-in strategy developed in this research shows a good agreement with experimental work.
Implementation of Steiner point of fuzzy set.
Liang, Jiuzhen; Wang, Dejiang
2014-01-01
This paper deals with the implementation of Steiner point of fuzzy set. Some definitions and properties of Steiner point are investigated and extended to fuzzy set. This paper focuses on establishing efficient methods to compute Steiner point of fuzzy set. Two strategies of computing Steiner point of fuzzy set are proposed. One is called linear combination of Steiner points computed by a series of crisp α-cut sets of the fuzzy set. The other is an approximate method, which is trying to find the optimal α-cut set approaching the fuzzy set. Stability analysis of Steiner point of fuzzy set is also studied. Some experiments on image processing are given, in which the two methods are applied for implementing Steiner point of fuzzy image, and both strategies show their own advantages in computing Steiner point of fuzzy set.
Applying the shelterwood system
Richard M. Godman
1992-01-01
The 2-cut shelterwood silvicultural system is the most reliable method we have for regenerating even-aged hardwoods. Unlike other systems it can be used for all hardwood species, both small- and large-seeded, but will probably be used most often for the small-seeded ones such as yellow birch, paper birch, and hemlock.
Cutting efficiency of a mid-infrared laser on human enamel.
Levy, G; Koubi, G F; Miserendino, L J
1998-02-01
In this study, the cutting ability of a newly developed dental laser was compared with a dental high-speed handpiece and rotary bur for removal of enamel. Measurements of the volume of tissue removed, energy emitted, and time of exposure were used to quantify the ablation rate (rate of tissue removal) for each test group and compared. Cutting efficiency (mm3/s) of the laser was calculated based on the mean volume of tissue removed per pulse (mm3/pulse) and unit energy expended (mm3/J) over the range of applied powers (2, 4, 6, and 8 W). The specimens were then examined by light microscopy and scanning electron micrographs for qualitative analysis of the amount of remaining debris and the presence of the smear layer on the prepared enamel surface. Calculations of the cutting efficiency of the laser over the range of powers tested revealed a linear relationship with the level of applied power. The maximum average rate of tissue removal by the laser was 0.256 mm3/s at 8 W, compared with 0.945 mm3/s by the dental handpiece. Light microscopy and scanning electron micrograph examinations revealed a reduction in the amount of remaining debris and smear layer in the laser-prepared enamel surfaces, compared with the conventional method. Based on the results of this study, the cutting efficiency of the high-speed handpiece and dental bur was 3.7 times greater than the laser over the range of powers tested, but the laser appeared to create a cleaner enamel surface with minimal thermal damage. Further modifications of the laser system are suggested for improvement of laser cutting efficiency.
Yu, Lu; Shi, Jing; Cao, Lianlian; Zhang, Guoping; Wang, Wenli; Hu, Deyu; Song, Baoan
2017-08-15
Southern rice black-streaked dwarf virus (SRBSDV) has spread from the south of China to the north of Vietnam in the past few years, and has severely influenced rice production. However, previous study of traditional SRBSDV transmission method by the natural virus vector, the white-backed planthopper (WBPH, Sogatella furcifera), in the laboratory, researchers are frequently confronted with lack of enough viral samples due to the limited life span of infected vectors and rice plants and low virus acquisition and inoculation efficiency by the vector. Meanwhile, traditional mechanical inoculation of virus only apply to dicotyledon because of the higher content of lignin in the leaves of the monocot. Therefore, establishing an efficient and persistent-transmitting model, with a shorter virus transmission time and a higher virus transmission efficiency, for screening novel anti-SRBSDV drugs is an urgent need. In this study, we firstly reported a novel method for transmitting SRBSDV in rice using the bud-cutting method. The transmission efficiency of SRBSDV in rice was investigated via the polymerase chain reaction (PCR) method and the replication of SRBSDV in rice was also investigated via the proteomics analysis. Rice infected with SRBSDV using the bud-cutting method exhibited similar symptoms to those infected by the WBPH, and the transmission efficiency (>80.00%), which was determined using the PCR method, and the virus transmission time (30 min) were superior to those achieved that transmitted by the WBPH. Proteomics analysis confirmed that SRBSDV P1, P2, P3, P4, P5-1, P5-2, P6, P8, P9-1, P9-2, and P10 proteins were present in infected rice seedlings infected via the bud-cutting method. The results showed that SRBSDV could be successfully transmitted via the bud-cutting method and plants infected SRBSDV exhibited the symptoms were similar to those transmitted by the WBPH. Therefore, the use of the bud-cutting method to generate a cheap, efficient, reliable supply of SRBSDV-infected rice seedlings should aid the development of disease control strategies. Meanwhile, this method also could provide a new idea for the other virus transmission in monocot.
Patch-based iterative conditional geostatistical simulation using graph cuts
NASA Astrophysics Data System (ADS)
Li, Xue; Mariethoz, Gregoire; Lu, DeTang; Linde, Niklas
2016-08-01
Training image-based geostatistical methods are increasingly popular in groundwater hydrology even if existing algorithms present limitations that often make real-world applications difficult. These limitations include a computational cost that can be prohibitive for high-resolution 3-D applications, the presence of visual artifacts in the model realizations, and a low variability between model realizations due to the limited pool of patterns available in a finite-size training image. In this paper, we address these issues by proposing an iterative patch-based algorithm which adapts a graph cuts methodology that is widely used in computer graphics. Our adapted graph cuts method optimally cuts patches of pixel values borrowed from the training image and assembles them successively, each time accounting for the information of previously stitched patches. The initial simulation result might display artifacts, which are identified as regions of high cost. These artifacts are reduced by iteratively placing new patches in high-cost regions. In contrast to most patch-based algorithms, the proposed scheme can also efficiently address point conditioning. An advantage of the method is that the cut process results in the creation of new patterns that are not present in the training image, thereby increasing pattern variability. To quantify this effect, a new measure of variability is developed, the merging index, quantifies the pattern variability in the realizations with respect to the training image. A series of sensitivity analyses demonstrates the stability of the proposed graph cuts approach, which produces satisfying simulations for a wide range of parameters values. Applications to 2-D and 3-D cases are compared to state-of-the-art multiple-point methods. The results show that the proposed approach obtains significant speedups and increases variability between realizations. Connectivity functions applied to 2-D models transport simulations in 3-D models are used to demonstrate that pattern continuity is preserved.
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.
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.
NASA Astrophysics Data System (ADS)
Haddag, B.; Kagnaya, T.; Nouari, M.; Cutard, T.
2013-01-01
Modelling machining operations allows estimating cutting parameters which are difficult to obtain experimentally and in particular, include quantities characterizing the tool-workpiece interface. Temperature is one of these quantities which has an impact on the tool wear, thus its estimation is important. This study deals with a new modelling strategy, based on two steps of calculation, for analysis of the heat transfer into the cutting tool. Unlike the classical methods, considering only the cutting tool with application of an approximate heat flux at the cutting face, estimated from experimental data (e.g. measured cutting force, cutting power), the proposed approach consists of two successive 3D Finite Element calculations and fully independent on the experimental measurements; only the definition of the behaviour of the tool-workpiece couple is necessary. The first one is a 3D thermomechanical modelling of the chip formation process, which allows estimating cutting forces, chip morphology and its flow direction. The second calculation is a 3D thermal modelling of the heat diffusion into the cutting tool, by using an adequate thermal loading (applied uniform or non-uniform heat flux). This loading is estimated using some quantities obtained from the first step calculation, such as contact pressure, sliding velocity distributions and contact area. Comparisons in one hand between experimental data and the first calculation and at the other hand between measured temperatures with embedded thermocouples and the second calculation show a good agreement in terms of cutting forces, chip morphology and cutting temperature.
Mohan, Alladi; Reddy, S. Aparna; Sachan, Alok; Sarma, K.V.S.; Kumar, D. Prabath; Panchagnula, Mahesh V.; Rao, P.V.L.N. Srinivasa; Kumar, B. Siddhartha; Krishnaprasanthi, P.
2016-01-01
Background & Objectives: Glycosylated haemoglobin (HbA1c) has been in use for more than a decade, as a diagnostic test for type 2 diabetes. Validity of HbA1c needs to be established in the ethnic population in which it is intended to be used. The objective of this study was to derive and validate a HbA1c cut-off value for the diagnosis of type 2 diabetes in the ethnic population of Rayalaseema area of south India. Methods: In this cross-sectional study, consecutive patients suspected to have type 2 diabetes underwent fasting plasma glucose (FPG) and 2 h post-load plasma glucose (2 h-PG) measurements after a 75 g glucose load and HbA1c estimation. They were classified as having diabetes as per the American Diabetes Association criteria [(FPG ≥7 mmol/l (≥126 mg/dl) and/or 2 h-PG ≥11.1 mmol/l (≥200 mg/dl)]. In the training data set (n = 342), optimum cut-off value of HbA1c for defining type 2 diabetes was derived by receiver-operator characteristic (ROC) curve method using oral glucose tolerance test results as gold standard. This cut-off was validated in a validation data set (n = 341). Results: On applying HbA1c cut-off value of >6.3 per cent (45 mmol/mol) to the training data set, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for diagnosing type 2 diabetes were calculated to be 90.6, 85.2, 80.8 and 93.0 per cent, respectively. When the same cut-off value was applied to the validation data set, sensitivity, specificity, PPV and NPV were 88.8, 81.9, 74.0 and 92.7 per cent, respectively, although the latter were consistently smaller than the proportions for the training data set, the differences being not significant. Interpretation & conclusions: HbA1c >6.3 per cent (45 mmol/mol) appears to be the optimal cut-off value for the diagnosis of type 2 diabetes applicable to the ethnic population of Rayalaseema area of Andhra Pradesh state in south India. PMID:27934801
Transfer of Campylobacter jejuni from raw to cooked chicken via wood and plastic cutting boards.
Tang, J Y H; Nishibuchi, M; Nakaguchi, Y; Ghazali, F M; Saleha, A A; Son, R
2011-06-01
We quantified Campylobacter jejuni transferred from naturally contaminated raw chicken fillets and skins to similar cooked chicken parts via standard rubberwood (RW) and polyethylene cutting boards (PE). RW and PE cutting boards (2.5 × 2.5 cm(2)) were constructed. RW surfaces were smooth and even, whereas PE was uneven. Scoring with scalpel blades produced crevices on RW and flaked patches on the PE boards. Raw chicken breast fillets or skin pieces (10 g) naturally contaminated with Camp. jejuni were used to contaminate the cutting boards (6.25 cm(2)). These were then briefly covered with pieces of cooked chicken. Campylobacter jejuni on raw chicken, the boards, and cooked chicken pieces were counted using a combined most-probable-number (MPN)-PCR method. The type of cutting board (RW, PE; unscored and scored) and temperature of cooked chicken fillets and skins were examined. Unscored PE and RW boards were not significantly different in regards to the mean transfer of Camp. jejuni from raw samples to the boards. The mean transfer of Camp. jejuni from scored RW was significantly higher than from scored PE. When the chicken fillets were held at room temperature, the mean transfer of Camp. jejuni from scored RW and PE was found to be 44.9 and 40.3%, respectively. RW and PE cutting boards are potential vehicles for Camp. jejuni to contaminate cooked chicken. Although cooked chicken maintained at high temperatures reduced cross-contamination via contaminated boards, a risk was still present. Contamination of cooked chicken by Camp. jejuni from raw chicken via a cutting board is influenced by features of the board (material, changes caused by scoring) and chicken (types of chicken parts and temperature of the cooked chicken). © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.
29 CFR 1915.55 - Gas welding and cutting.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 7 2014-07-01 2014-07-01 false Gas welding and cutting. 1915.55 Section 1915.55 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.55 Gas welding and cutting. The provisions of this section shall apply to ship repairing...
29 CFR 1915.56 - Arc welding and cutting.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 7 2014-07-01 2014-07-01 false Arc welding and cutting. 1915.56 Section 1915.56 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Welding, Cutting and Heating § 1915.56 Arc welding and cutting. The provisions of this section shall apply to ship repairing...
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.
The LS-STAG immersed boundary/cut-cell method for non-Newtonian flows in 3D extruded geometries
NASA Astrophysics Data System (ADS)
Nikfarjam, F.; Cheny, Y.; Botella, O.
2018-05-01
The LS-STAG method is an immersed boundary/cut-cell method for viscous incompressible flows based on the staggered MAC arrangement for Cartesian grids, where the irregular boundary is sharply represented by its level-set function, results in a significant gain in computer resources (wall time, memory usage) compared to commercial body-fitted CFD codes. The 2D version of LS-STAG method is now well-established (Cheny and Botella, 2010), and this paper presents its extension to 3D geometries with translational symmetry in the z direction (hereinafter called 3D extruded configurations). This intermediate step towards the fully 3D implementation can be applied to a wide variety of canonical flows and will be regarded as the keystone for the full 3D solver, since both discretization and implementation issues on distributed memory machines are tackled at this stage of development. The LS-STAG method is then applied to various Newtonian and non-Newtonian flows in 3D extruded geometries (axisymmetric pipe, circular cylinder, duct with an abrupt expansion) for which benchmark results and experimental data are available. The purpose of these investigations are (a) to investigate the formal order of accuracy of the LS-STAG method, (b) to assess the versatility of method for flow applications at various regimes (Newtonian and shear-thinning fluids, steady and unsteady laminar to turbulent flows) (c) to compare its performance with well-established numerical methods (body-fitted and immersed boundary methods).
Endoscopic removal of over-the-scope clips: Clinical experience with a bipolar cutting device
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
Parallax handling of image stitching using dominant-plane homography
NASA Astrophysics Data System (ADS)
Pang, Zhaofeng; Li, Cheng; Zhao, Baojun; Tang, Linbo
2015-10-01
In this paper, we present a novel image stitching method to handle parallax in practical application. For images with significant amount of parallax, the more effective approach is to align roughly and globally the overlapping regions and then apply a seam-cutting method to composite naturally stitched images. It is well known that images can be modeled by various planes result from the projective parallax under non-ideal imaging condition. The dominant-plane homography has important advantages of warping an image globally and avoiding some local distortions. The proposed method primarily addresses large parallax problem through two steps: (1) selecting matching point pairs located on the dominant plane, by clustering matching correspondences and then measuring the cost of each cluster; and (2) in order to obtain a plausible seam, edge maps of overlapped area incorporation arithmetic is adopted to modify the standard seam-cutting method. Furthermore, our approach is demonstrated to achieve reliable performance of handling parallax through a mass of experimental comparisons with state-of-the-art methods.
Taking Charge of Professional Development: A Practical Model for Your School
ERIC Educational Resources Information Center
Semadeni, Joseph
2009-01-01
Overcome budget cuts, lack of leadership, top-down mandates, and other obstacles to professional development by using this book's take-charge approach. Joseph H. Semadeni guides you through a systemic method to professional development that: (1) Motivates teachers to continuously learn and apply best practices; (2) Makes adult learning activities…
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.
Mechanisms and FEM Simulation of Chip Formation in Orthogonal Cutting In-Situ TiB2/7050Al MMC
Wang, Wenhu; Jiang, Ruisong; Lin, Kunyang; Shao, Mingwei
2018-01-01
The in-situ TiB2/7050Al composite is a new kind of Al-based metal matrix composite (MMC) with super properties, such as low density, improved strength, and wear resistance. This paper, for a deep insight into its cutting performance, involves a study of the chip formation process and finite element simulation during orthogonal cutting in-situ TiB2/7050Al MMC. With chips, material properties, cutting forces, and tool geometry parameters, the Johnson–Cook (J–C) constitutive equation of in-situ TiB2/7050Al composite was established. Then, the cutting simulation model was established by applying the Abaqus–Explicit method, and the serrated chip, shear plane, strain rate, and temperature were analyzed. The experimental and simulation results showed that the obtained material’s constitutive equation was of high reliability, and the saw-tooth chips occurred commonly under either low or high cutting speed and small or large feed rate. From result analysis, it was found that the mechanisms of chip formation included plastic deformation, adiabatic shear, shearing slip, and crack extension. In addition, it was found that the existence of small, hard particles reduced the ductility of the MMC and resulted in segmental chips. PMID:29662047
Xia, Qian Hua; Zheng, Li Ping; Zhao, Pei Fei; Wang, Jian Wen
2017-03-01
A biological method for synthesising silver nanoparticles (AgNPs) was developed using the callus extracts from Artemisia annua L. under sunlight at 25,000 lx. The AgNPs were characterised using transmission electron microscopy, atomic force microscope, X-ray diffraction and Fourier transform infrared spectroscopy. The AgNPs were mostly spherical with the size of 2.1 to 45.2 nm (average 10.9 nm). Pulse treatments of AgNPs at 125, 250 and 500 mg/l for 1 h extended vase life of cut carnation ( Dianthus caryophyllus cv. Green Land) flowers. Four dominant bacteria strains Arthrobacter arilaitensis, Kocuria sp., Staphylococcus equorum and Microbacterium oxydans were isolated from the stem-ends of cut D. caryophyllus flowers. AgNP pulse inhibited significantly bacterial growth in vase solution and cut stem ends during all of the vase period. The bacteria related blockage in the stem-ends was significantly alleviated by AgNP pulse because of its higher antibacterial efficacy against the dominant bacteria. In addition, ethylene release of cut carnation flowers was inhibited in response to AgNP pulse. This is the first time that the biologically synthesised AgNPs could be applied as a promising preservative agent for cut carnation flowers.
NASA Astrophysics Data System (ADS)
Norcahyo, Rachmadi; Soepangkat, Bobby O. P.
2017-06-01
A research was conducted for the optimization of the end milling process of ASSAB XW-42 tool steel with multiple performance characteristics based on the orthogonal array with Taguchi-grey relational analysis method. Liquid nitrogen was applied as a coolant. The experimental studies were conducted under varying the liquid nitrogen cooling flow rates (FL), and the end milling process variables, i.e., cutting speed (Vc), feeding speed (Vf), and axial depth of cut (Aa). The optimized multiple performance characteristics were surface roughness (SR), flank wear (VB), and material removal rate (MRR). An orthogonal array, signal-to-noise (S/N) ratio, grey relational analysis, grey relational grade, and analysis of variance were employed to study the multiple performance characteristics. Experimental results showed that flow rate gave the highest contribution for reducing the total variation of the multiple responses, followed by cutting speed, feeding speed, and axial depth of cut. The minimum surface roughness, flank wear, and maximum material removal rate could be obtained by using the values of flow rate, cutting speed, feeding speed, and axial depth of cut of 0.5 l/minute, 109.9 m/minute, 440 mm/minute, and 0.9 mm, respectively.
NASA Astrophysics Data System (ADS)
Shrivastava, Prashant Kumar; Pandey, Arun Kumar
2018-06-01
Inconel-718 has found high demand in different industries due to their superior mechanical properties. The traditional cutting methods are facing difficulties for cutting these alloys due to their low thermal potential, lower elasticity and high chemical compatibility at inflated temperature. The challenges of machining and/or finishing of unusual shapes and/or sizes in these materials have also faced by traditional machining. Laser beam cutting may be applied for the miniaturization and ultra-precision cutting and/or finishing by appropriate control of different process parameter. This paper present multi-objective optimization the kerf deviation, kerf width and kerf taper in the laser cutting of Incone-718 sheet. The second order regression models have been developed for different quality characteristics by using the experimental data obtained through experimentation. The regression models have been used as objective function for multi-objective optimization based on the hybrid approach of multiple regression analysis and genetic algorithm. The comparison of optimization results to experimental results shows an improvement of 88%, 10.63% and 42.15% in kerf deviation, kerf width and kerf taper, respectively. Finally, the effects of different process parameters on quality characteristics have also been discussed.
Funkenbusch, Paul D; Rotella, Mario; Chochlidakis, Konstantinos; Ercoli, Carlo
2016-10-01
Laboratory studies of tooth preparation often involve single values for all variables other than the one being tested. In contrast, in clinical settings, not all variables can be adequately controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but, in clinical practice, the instrument must make different cuts with individual dentists applying different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies difficult. The purpose of this in vitro study was to examine the effects of 9 process variables on the dental cutting of rotary cutting instruments used with an electric handpiece and compare them with those of a previous study that used an air-turbine handpiece. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using an electric handpiece in a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures with Macor blocks as the cutting substrate. Analysis of variance (ANOVA) was used to assess the statistical significance (α=.05). Four variables (targeted applied load, cut length, diamond grit size, and cut type) consistently produced large, statistically significant effects, whereas 5 variables (rotation per minute, number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate) produced relatively small, statistically insignificant effects. These results are generally similar to those previously found for an air-turbine handpiece. Regardless of whether an electric or air-turbine handpiece was used, the control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances and hardware choices. These results highlight the greater importance of local clinical conditions (procedure, dentist) in understanding dental cutting as opposed to other hardware-related factors. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Funkenbusch, Paul D; Rotella, Mario; Ercoli, Carlo
2015-04-01
Laboratory studies of tooth preparation are often performed under a limited range of conditions involving single values for all variables other than the 1 being tested. In contrast, in clinical settings not all variables can be tightly controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but in clinical practice, the instrument must make different cuts with individual dentists applying a range of different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies is difficult. The purpose of this study was to examine the effect of 9 process variables on dental cutting in a single experiment, allowing each variable to be robustly tested over a range of values for the other 8 and permitting a direct comparison of the relative importance of each on the cutting process. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures and Macor blocks as the cutting substrate. Analysis of Variance (ANOVA) was used to judge the statistical significance (α=.05). Five variables consistently produced large, statistically significant effects (target applied load, cut length, starting rpm, diamond grit size, and cut type), while 4 variables produced relatively small, statistically insignificant effects (number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate). The control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances as well as hardware choices. These results highlight the importance of local clinical conditions (procedure, dentist) in understanding dental cutting procedures and in designing adequate experimental methodologies for future studies. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Finite pure integer programming algorithms employing only hyperspherically deduced cuts
NASA Technical Reports Server (NTRS)
Young, R. D.
1971-01-01
Three algorithms are developed that may be based exclusively on hyperspherically deduced cuts. The algorithms only apply, therefore, to problems structured so that these cuts are valid. The algorithms are shown to be finite.
Oak Regeneration Following Three Cutting Treatments on Mountain Slopes in Northern Alabama
Michael S. Golden; Mark R. Dubois; Jeffery L. Stockman
1999-01-01
Early regeneration success of upland oaks (Quercus spp. L.) was compared for three regeneration cutting treatments in the Sandstone Mountain Region of northern Alabama. Two 4-acre replications each of block dearcutting, strip cutting, and deferment cutting were established on north-facing slopes. The three harvesting treatments were applied in...
The Oxygen Dissociation Curve of Hemoglobin: Bridging the Gap between Biochemistry and Physiology
NASA Astrophysics Data System (ADS)
Gómez-Cambronero, Julian
2001-06-01
Cooperativity is a very difficult concept for biochemistry students in the health sciences. An analogy between breaking salt bonds and tearing apart a block of four stamps has been proposed for hemoglobin (Hb). However, since tearing is equated to binding of molecules, two intrinsically contradictory terms, students still have difficulty. I apply the pictorial analogy to the releasing of oxygen instead of the binding, thus bridging biochemistry (cooperativity) with physiology (oxygen dissociation). I embark on an imaginary journey from the lungs (saturation at 100 mmHg) to the oxygen-starved tissues. The stamps represent fully loaded Hb. By making two cuts the first "oxygen" is released. For the second, only one cut is needed. With one final cut, the last two stamps are separated. This means that less energy is needed to unload oxygen: just small drops in partial pressure do the trick in the right place (tissues) but not in the wrong one (lungs). In doing this, I use the three main models of learning: association, discovery and mentoring. Additionally, by guiding students to discover the truth by themselves, I can use hemoglobin as a wonderful excuse to apply the "Socratic method" in the classroom.
Jacups, Susan P; Whelan, Peter I; Harley, David
2011-03-01
Ross River virus (RRV) causes the most common human arbovirus disease in Australia. Although the disease is nonfatal, the associated arthritis and postinfection fatigue can be debilitating for many months, impacting on workforce participation. We sought to create an early-warning system to notify of approaching RRV disease outbreak conditions for major townships in the Northern Territory. By applying a logistic regression model to meteorologic factors, including rainfall, a postestimation analysis of sensitivity and specificity can create rainfall cut-points. These rainfall cut-points indicate the rainfall level above which previous epidemic conditions have occurred. Furthermore, rainfall cut-points indirectly adjust for vertebrate host data from the agile wallaby (Macropus agilis) as the life cycle of the agile wallaby is intricately meshed with the wet season. Once generated, cut-points can thus be used prospectively to allow timely implementation of larval survey and control measures and public health warnings to preemptively reduce RRV disease incidence. Cut-points are location specific and have the capacity to replace previously used models, which require data management and input, and rarely provide timely notification for vector control requirements and public health warnings. These methods can be adapted for use elsewhere.
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.
Michael G. Shelton
1997-01-01
The shelterwood reproduction cutting method using two overstory compositions (a pine basal area of 30 ft* per acre with and without 15 ftâ per acre of hardwoods) and two methods of submerchantable hardwood control (chain-saw felling with and without stump-applied herbicide) was tested in a 2x2 factorial, split-plot design with four randomized complete blocks....
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.
Applying Rasch Model and Generalizability Theory to Study Modified-Angoff Cut Scores
ERIC Educational Resources Information Center
Arce, Alvaro J.; Wang, Ze
2012-01-01
The traditional approach to scale modified-Angoff cut scores transfers the raw cuts to an existing raw-to-scale score conversion table. Under the traditional approach, cut scores and conversion table raw scores are not only seen as interchangeable but also as originating from a common scaling process. In this article, we propose an alternative…
Epidermal electronic systems for sensing and therapy
NASA Astrophysics Data System (ADS)
Lu, Nanshu; Ameri, Shideh K.; Ha, Taewoo; Nicolini, Luke; Stier, Andrew; Wang, Pulin
2017-04-01
Epidermal electronic system is a class of hair thin, skin soft, stretchable sensors and electronics capable of continuous and long-term physiological sensing and clinical therapy when applied on human skin. The high cost of manpower, materials, and photolithographic facilities associated with its manufacture limit the availability of disposable epidermal electronics. We have invented a cost and time effective, completely dry, benchtop "cut-and-paste" method for the green, freeform and portable manufacture of epidermal electronics within minutes. We have applied the "cut-and-paste" method to manufacture epidermal electrodes, hydration and temperature sensors, conformable power-efficient heaters, as well as cuffless continuous blood pressure monitors out of metal thin films, two-dimensional (2D) materials, and piezoelectric polymer sheets. For demonstration purpose, we will discuss three examples of "cut-and-pasted" epidermal electronic systems in this paper. The first will be submicron thick, transparent epidermal graphene electrodes that can be directly transferred to human skin like a temporary transfer tattoo and can measure electrocardiogram (ECG) with signal-to-noise ratio and motion artifacts on par with conventional gel electrodes. The second will be a chest patch which houses both electrodes and pressure sensors for the synchronous measurements of ECG and seismocardiogram (SCG) such that beat-to-beat blood pressure can be inferred from the time interval between the R peak of the ECG and the AC peak of the SCG. The last example will be a highly conformable, low power consumption epidermal heater for thermal therapy.
Yanagawa, T; Tokudome, S
1990-01-01
We developed methods to assess the cancer risks by screening tests. These methods estimate the size of the high risk group adjusted for the characteristics of screening tests and estimate the incidence rates of cancer among the high risk group adjusted for the characteristics of the tests. A method was also developed for selecting the cut-off point of a screening test. Finally, the methods were applied to estimate the risk of the adult T-cell leukemia/lymphoma. PMID:2269244
The Rational Approach to Budget Cuts: One University's Experience. ASHE 1987 Annual Meeting Paper.
ERIC Educational Resources Information Center
Hardy, Cynthia
The experiences of the University of Montreal in using a rational-analytic framework to allocate resources at a time of budget costs are discussed. The following characteristics for rational decision-making are identified and applied to the University of Montreal: whether goals were known, whether alternative methods of resource allocation were…
Policy Mobilities and Methodology: A Proposition for Inventive Methods in Education Policy Studies
ERIC Educational Resources Information Center
Gulson, Kalervo N.; Lewis, Steven; Lingard, Bob; Lubienski, Christopher; Takayama, Keita; Webb, P. Taylor
2017-01-01
The argument of this paper is that new methodologies associated with the emerging field of "policy mobilities" can be applied, and are in fact required, to examine and research the networked and relational, or "topological", nature of globalised education policy, which cuts across the new spaces of policymaking and new modes of…
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…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-27
...'s and boys' worsted wool suits and suit-like jackets and trousers in the United States and who apply for an allocation based on the amount of such suits cut and sewn during the prior calendar year... be reallocated. II. Method of Collection Forms are available on the Internet and by mail to...
NASA Astrophysics Data System (ADS)
Chlebowski, Dariusz; Zorychta, Andrzej; Burtan, Zbigniew; Cała, Marek
2017-03-01
The paper outlines the main objectives of the method used for assessment of rockburst hazard during longwall mining operations taking into account factors expressing the confined work conditions. Relying on analytical approach, the conditions are examined that are likely to trigger the rockburst occurrence along the face, with regards to the location of cross-cuts and taking into account the presence of past excavation and geological disorders in the overlying strata. Simulation data apply to three cases of model loading, representing the impacts of residual pillars, gobs surrounded by undisturbed blocks of coal and the presence of faults, whilst the procedure involves five possible locations of opening-out cross-cuts in relation to characteristic points in the model. Results are examined basing on variability patterns of stress concentration and energy density distribution in the proximity of the workface in the course of progressing mining operations.
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.
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.
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.
He, Y; Zhang, W; Huang, T; Wang, X; Wang, M
2015-10-01
To evaluate a diagnostic flow chart applying medical thoracoscoy (MT), adenosine deaminase (ADA) and T-SPOT.TB in diagnosis of tuberculous pleural effusion (TPE) at a high TB burden country. 136 patients with pleural effusion (PE) were enrolled and divided into TPE and Non-TPE group. MT (histology), PE ADA and T-SPOT.TB were conducted on all patients. ROC analysis was performed for the best cut-off value of PE ADA in detection of TPE. The diagnostic flow chart applying MT, ADA and T-SPOT.TB was evaluated for improving the limitations of each diagnostic method. ROC analysis showed that the best cut-off value of PE ADA was 30U/L. The sensitivity and specificity of these tests were calculated respectively to be: 71.4% (58.5%-81.6%) and 100% (95.4-100.0%) for MT, 92.9% (83.0-97.2%) and 68.8% (57.9-77.9%) for T-SPOT.TB, and 80.0% (69.6-88.1%) and 92.9% (82.7-98.0%) for PE ADA. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value and negative predictive value of the diagnostic flow chart were 96.4% (87.9-99.0%), 96.3% (89.6-98.7%), 25.714, 0.037, 97.4 and 94.9, respectively. The diagnostic flow chart applying MT, ADA and T-SPOT.TB is an accurate and rapid diagnostic method in detection of TPE.
Qin, Sheng; Li, Zhongquan; Guo, Guoqiang; An, Qinglong; Chen, Ming; Ming, Weiwei
2016-09-28
The tool coating and cooling strategy are two key factors when machining difficult-to-cut materials such as titanium alloy. In this paper, diamond coating was deposited on a commercial carbide insert as an attempt to increase the machinability of TC11 alloy during the turning process. An uncoated carbide insert and a commercial Al₂O₃/TiAlN-coated tool were also tested as a comparison. Furthermore, MQL was applied to improve the cutting condition. Cutting performances were analyzed by cutting force, cutting temperate and surface roughness measurements. Tool wears and tool lives were evaluated to find a good matchup between the tool coating and cooling strategy. According to the results, using MQL can slightly reduce the cutting force. By applying MQL, cutting temperatures and tool wears were reduced by a great amount. Besides, MQL can affect the tool wear mechanism and tool failure modes. The tool life of an Al₂O₃/TiAlN-coated tool can be prolonged by 88.4% under the MQL condition. Diamond-coated tools can obtain a good surface finish when cutting parameters and lubrication strategies are properly chosen.
Qin, Sheng; Li, Zhongquan; Guo, Guoqiang; An, Qinglong; Chen, Ming; Ming, Weiwei
2016-01-01
The tool coating and cooling strategy are two key factors when machining difficult-to-cut materials such as titanium alloy. In this paper, diamond coating was deposited on a commercial carbide insert as an attempt to increase the machinability of TC11 alloy during the turning process. An uncoated carbide insert and a commercial Al2O3/TiAlN-coated tool were also tested as a comparison. Furthermore, MQL was applied to improve the cutting condition. Cutting performances were analyzed by cutting force, cutting temperate and surface roughness measurements. Tool wears and tool lives were evaluated to find a good matchup between the tool coating and cooling strategy. According to the results, using MQL can slightly reduce the cutting force. By applying MQL, cutting temperatures and tool wears were reduced by a great amount. Besides, MQL can affect the tool wear mechanism and tool failure modes. The tool life of an Al2O3/TiAlN-coated tool can be prolonged by 88.4% under the MQL condition. Diamond-coated tools can obtain a good surface finish when cutting parameters and lubrication strategies are properly chosen. PMID:28773926
Application of laser spot cutting on spring contact probe for semiconductor package inspection
NASA Astrophysics Data System (ADS)
Lee, Dongkyoung; Cho, Jungdon; Kim, Chan Ho; Lee, Seung Hwan
2017-12-01
A packaged semiconductor has to be electrically tested to make sure they are free of any manufacturing defects. The test interface, typically employed between a Printed Circuit Board and the semiconductor devices, consists of densely populated Spring Contact Probe (SCP). A standard SCP typically consists of a plunger, a barrel, and an internal spring. Among these components, plungers are manufactured by a stamping process. After stamping, plunger connecting arms need to be cut into pieces. Currently, mechanical cutting has been used. However, it may damage to the body of plungers due to the mechanical force engaged at the cutting point. Therefore, laser spot cutting is considered to solve this problem. The plunger arm is in the shape of a rectangular beam, 50 μm (H) × 90 μm (W). The plunger material used for this research is gold coated beryllium copper. Laser parameters, such as power and elapsed time, have been selected to study laser spot cutting. Laser material interaction characteristics such as a crater size, material removal zone, ablation depth, ablation threshold, and full penetration are observed. Furthermore, a carefully chosen laser parameter (Etotal = 1000mJ) to test feasibility of laser spot cutting are applied. The result show that laser spot cutting can be applied to cut SCP.
Diameter-limit cutting in Appalachian hardwoods: boon or bane?
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...
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’.
Some aspects of precise laser machining - Part 2: Experimental
NASA Astrophysics Data System (ADS)
Grabowski, Marcin; Wyszynski, Dominik; Ostrowski, Robert
2018-05-01
The paper describes the role of laser beam polarization on quality of laser beam machined cutting tool edge. In micromachining the preparation of the cutting tools in play a key role on dimensional accuracy, sharpness and the quality of the cutting edges. In order to assure quality and dimensional accuracy of the cutting tool edge it is necessary to apply laser polarization control. In the research diode pumped Nd:YAG 532nm pulse laser was applied. Laser beam polarization used in the research was linear (horizontal, vertical). The goal of the carried out research was to describe impact of laser beam polarization on efficiency of the cutting process and quality of machined parts (edge, surface) made of polycrystalline diamond (PCD) and cubic boron nitride (cBN). Application of precise cutting tool in micromachining has significant impact on the minimum uncut chip thickness and quality of the parts. The research was carried within the INNOLOT program funded by the National Centre for Research and Development.
NASA Astrophysics Data System (ADS)
Lin, S. Y.; Chung, C. T.; Cheng, Y. Y.
2011-01-01
The main objective of this study is to develop a thermo-elastic-plastic coupling model, based on a combination skill of ultrasonically assisted cutting and cryogenic cooling, under large deformation for Inconel 718 alloy machining process. The improvement extent on cutting performance and tool life promotion may be examined from this investigation. The critical value of the strain energy density of the workpiece will be utilized as the chip separation and the discontinuous chip segmentation criteria. The forced convection cooling and a hydrodynamic lubrication model will be considered and formulated in the model. Finite element method will be applied to create a complete numerical solution for this ultrasonic vibration cutting model. During the analysis, the cutting tool is incrementally advanced forward with superimposed ultrasonic vibration in a back and forth step-by-step manner, from an incipient stage of tool-workpiece engagement to a steady state of chip formation, a whole simulation of orthogonal cutting process under plane strain deformation is thus undertaken. High shear strength induces a fluctuation phenomenon of shear angle, high shear strain rate, variation of chip types and chip morphology, tool-chip contact length variation, the temperature distributions within the workpiece, chip and tool, periodic fluctuation in cutting forces can be determined from the developed model. A complete comparison of machining characteristics between some different combinations of ultrasonically assisted cutting and cryogenic cooling with conventional cutting operation can be acquired. Finally, the high-speed turning experiment for Inconel 718 alloy will be taken in the laboratory to validate the accuracy of the model, and the progressive flank wear, crater wear, notching and chipping of the tool edge can also be measured in the experiments.
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.
16 CFR 23.16 - Misuse of the words “brilliant” and “full cut.”
Code of Federal Regulations, 2014 CFR
2014-01-01
...,” “brilliant cut,” or “full cut” to describe, identify, or refer to any diamond except a round diamond that has... below. Note to § 23.16: Such terms should not be applied to single or rose-cut diamonds. They may be...) cut diamonds meeting the above-stated facet requirements when, in immediate conjunction with the term...
16 CFR 23.16 - Misuse of the words “brilliant” and “full cut.”
Code of Federal Regulations, 2013 CFR
2013-01-01
...,” “brilliant cut,” or “full cut” to describe, identify, or refer to any diamond except a round diamond that has... below. Note to § 23.16: Such terms should not be applied to single or rose-cut diamonds. They may be...) cut diamonds meeting the above-stated facet requirements when, in immediate conjunction with the term...
16 CFR 23.16 - Misuse of the words “brilliant” and “full cut.”
Code of Federal Regulations, 2012 CFR
2012-01-01
...,” “brilliant cut,” or “full cut” to describe, identify, or refer to any diamond except a round diamond that has... below. Note to § 23.16: Such terms should not be applied to single or rose-cut diamonds. They may be...) cut diamonds meeting the above-stated facet requirements when, in immediate conjunction with the term...
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...
Restoration of Aspen-Dominated Ecosystem in the Lake States
Douglas M. Stone; John D. Elioff; Donald V. Potter; Donald B. Peterson; Robert Wagner
2001-01-01
A reserve tree method(RTM)of harvesting was installed in six 70-to75-year-old aspen-dominated stands to determine if retaining 10 to 15 dominant aspen per acre would decrease sucker density to facilitate restoration of a conifer component. A reserve shelterwood cut was applied to three additional stands to evaluate performance of white pine planted under 50% crown...
Restoration of aspen-dominated ecosystems in the Lake States
Douglas M. Stone; John D. Elioff; Donald V. Potter; Donald B. Peterson; Robert Wagner
2000-01-01
A reserve tree method (RTM) of harvesting was installed in six 70-to75-year old aspen-dominated stands to determine if retaining 10 to 15 dominant aspen per acre would decrease sucker density to facilitate restoration of a conifer component. A reserve shelterwood cut was applied to three additional stands to evaluate performance of white pine planted under 50% crown...
Restoration of aspen-dominated ecosystems in the Lake States
Douglas M. Stone; John D. Elioff; Donald V. Potter; Donald B. Peterson; Robert Wagner
2001-01-01
A reserve tree method (RTM) of harvesting was installed in six 70- to 75-yearold aspen-dominated stands to determine if retaining 10 to 15 dominant aspen per acre would decrease sucker density to facilitate restoration of a conifer component. A reserve shelterwood cut was applied to three additional stands to evaluate performance of white pine planted under 50% crown...
Karthikeyan, A; Chandrasekaran, K; Geetha, M; Kalaiselvi, R
2013-11-01
Casuarina equisetifolia Forst. is a tree crop that provides fuel wood, land reclamation, dune stabilization, and scaffolding for construction, shelter belts, and pulp and paper production. C. equisetifolia fixes atmospheric nitrogen through a symbiotic relationship with Frankia, a soil bacterium of the actinobacteria group. The roots of C. equisetifolia produce root nodules where the bacteria fix atmospheric nitrogen, which is an essential nutrient for all plant metabolic activities. However, rooted stem cuttings of elite clones of C. equisetifolia by vegetative propagation is being planted by the farmers of Pondicherry as costeffective method. As the vegetative propagation method uses inert material (vermiculite) for rooting there is no chance for Frankia association. Therefore after planting of these stocks the farmers are applying 150 kg of di-ammonium phosphate (DAP)/acre/year. To overcome this fertilizer usage, the Frankia-inoculated rooted stem cuttings were propagated under nursery conditions and transplanted in the nutrient-deficient soils of Karaikal, Pondicherry (India), in this study. Under nursery experiments the growth and biomass of C. equisetifolia rooted stem cuttings inoculated with Frankia showed 3 times higher growth and biomass than uninoculated control. These stocks were transplanted and monitored for their growth and survival for 1 year in the nutrient-deficient farm land. The results showed that the rooted stem cuttings of C. equisetifolia significantly improved growth in height (8.8 m), stem girth (9.6 cm) and tissue nitrogen content (3.3 mg g-1) than uninoculated controls. The soil nutrient status was also improved due to inoculation of Frankia.
The machined surface of magnesium AZ31 after rotary turning at air cooling condition
NASA Astrophysics Data System (ADS)
Akhyar, G.; Purnomo, B.; Hamni, A.; Harun, S.; Burhanuddin, Y.
2018-04-01
Magnesium is a lightweight metal that is widely used as an alternative to iron and steel. Magnesium has been applied in the automotive industry to reduce the weight of a component, but the machining process has the disadvantage that magnesium is highly flammable because it has a low flash point. High temperature can cause the cutting tool wear and contributes to the quality of the surface roughness. The purpose of this study is to obtain the value of surface roughness and implement methods of rotary cutting tool and air cooling output vortex tube cooler to minimize the surface roughness values. Machining parameters that is turning using rotary cutting tool at speed the workpiece of (Vw) 50, 120, 160 m/min, cutting speed of rotary tool of (Vt) 25, 50, 75 m/min, feed rate of (f) 0.1, 0.15, 0.2 mm/rev, and depth of cut of 0.3 mm. Type of tool used is a carbide tool diameter of 16 mm and air cooling pressure of 6 bar. The results show the average value of the lowest surface roughness on the speed the workpiece of 80 m/min, cutting speed of rotary tool of 50 m/min, feed rate of 0.2 mm/rev, and depth of cut of 0.3 mm. While the average value of the highest surface roughness on the speed the workpiece of 160 m/min, cutting speed of rotary tool of 50 m/min, feed rate of 0.2 mm/rev, and depth of cut of 0.3 mm. The influence of machining parameters concluded the higher the speed of the workpiece the surface roughness value higher. Otherwise the higher cutting speed of rotary tool then the lower the surface roughness value. The observation on the surface of the rotary tool, it was found that no uniform tool wear which causes non-uniform surface roughness. The use of rotary cutting tool contributing to lower surface roughness values generated.
Material properties and laser cutting of composites
NASA Astrophysics Data System (ADS)
Chen, Chia-Chieh; Cheng, Wing
Laser (Light Amplification by Stimulated Emission of Radiation) has been used successfully for many material cutting, drilling, metal welding and heat treating applications. However, laser cutting of polymer composites were attempted with varying degrees of success. Because composites are heterogeneous, the energy applied by laser could result in severe resin degradation before fibers were cut. In this study, cutting of glass, Kevlar, and graphite composites were evaluated based on their material properties and laser cutting parameters. A transient heat transfer analysis was used to determine the relative heat affected zones of these composites. Kevlar composites can be cut very well while graphite composites are difficult to cut. Though the cutting process is much more complicated in reality, the analysis provides a semi-quantitative perspective on the characteristics and limitations of laser cutting of different composites.
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...
Extending the time interval for applying herbicide in cut-stump treatments on American beech
Jeffrey D. Kochenderfer; James N. Kochenderfer; Gary W. Miller
2013-01-01
American Beech (Fagus grandifolia Ehrh.) root sprouts often form dense understories that interfere with tree reproduction throughout much of the eastern hardwood region. The cut-stump treatment, whereby herbicide is applied to the stump within a few hours after a larger beech is felled, has been shown to mitigate the interference problem by...
Cut Next Winter's Heating Bill Today.
ERIC Educational Resources Information Center
Sturgeon, Julie
1999-01-01
Presents specific steps that help make schools energy efficient and cut costs. Four basic strategies are suggested that include creating a database of energy usage that can also catch the occasional billing error, investigating less obvious ways of cutting energy use, such as applying cellulose commercial spray as an insulation choice, and…
Maximizing adhesion of auxin solutions to stem cuttings using sodium cellulose glycolate
USDA-ARS?s Scientific Manuscript database
Auxin solutions prepared with sodium cellulose glycolate (SCG; a thickening agent, also known as sodium carboxymethylcellulose) and applied to stem cuttings using a basal quick-dip extend the duration of exposure of cuttings to the auxin and have previously been shown to increase root number and/or ...
An Exact Algorithm to Compute the Double-Cut-and-Join Distance for Genomes with Duplicate Genes.
Shao, Mingfu; Lin, Yu; Moret, Bernard M E
2015-05-01
Computing the edit distance between two genomes is a basic problem in the study of genome evolution. The double-cut-and-join (DCJ) model has formed the basis for most algorithmic research on rearrangements over the last few years. The edit distance under the DCJ model can be computed in linear time for genomes without duplicate genes, while the problem becomes NP-hard in the presence of duplicate genes. In this article, we propose an integer linear programming (ILP) formulation to compute the DCJ distance between two genomes with duplicate genes. We also provide an efficient preprocessing approach to simplify the ILP formulation while preserving optimality. Comparison on simulated genomes demonstrates that our method outperforms MSOAR in computing the edit distance, especially when the genomes contain long duplicated segments. We also apply our method to assign orthologous gene pairs among human, mouse, and rat genomes, where once again our method outperforms MSOAR.
Micropunching lithography for generating micro- and submicron-patterns on polymer substrates.
Chakraborty, Anirban; Liu, Xinchuan; Luo, Cheng
2012-07-02
Conducting polymers have attracted great attention since the discovery of high conductivity in doped polyacetylene in 1977(1). They offer the advantages of low weight, easy tailoring of properties and a wide spectrum of applications(2,3). Due to sensitivity of conducting polymers to environmental conditions (e.g., air, oxygen, moisture, high temperature and chemical solutions), lithographic techniques present significant technical challenges when working with these materials(4). For example, current photolithographic methods, such as ultra-violet (UV), are unsuitable for patterning the conducting polymers due to the involvement of wet and/or dry etching processes in these methods. In addition, current micro/nanosystems mainly have a planar form(5,6). One layer of structures is built on the top surfaces of another layer of fabricated features. Multiple layers of these structures are stacked together to form numerous devices on a common substrate. The sidewall surfaces of the microstructures have not been used in constructing devices. On the other hand, sidewall patterns could be used, for example, to build 3-D circuits, modify fluidic channels and direct horizontal growth of nanowires and nanotubes. A macropunching method has been applied in the manufacturing industry to create macropatterns in a sheet metal for over a hundred years. Motivated by this approach, we have developed a micropunching lithography method (MPL) to overcome the obstacles of patterning conducting polymers and generating sidewall patterns. Like the macropunching method, the MPL also includes two operations (Fig. 1): (i) cutting; and (ii) drawing. The "cutting" operation was applied to pattern three conducting polymers(4), polypyrrole (PPy), Poly(3,4-ethylenedioxythiophen)-poly(4-styrenesulphonate) (PEDOT) and polyaniline (PANI). It was also employed to create Al microstructures(7). The fabricated microstructures of conducting polymers have been used as humidity(8), chemical(8), and glucose sensors(9). Combined microstructures of Al and conducting polymers have been employed to fabricate capacitors and various heterojunctions(9,10,11). The "cutting" operation was also applied to generate submicron-patterns, such as 100- and 500-nm-wide PPy lines as well as 100-nm-wide Au wires. The "drawing" operation was employed for two applications: (i) produce Au sidewall patterns on high density polyethylene (HDPE) channels which could be used for building 3D microsystems(12,13,14), and (ii) fabricate polydimethylsiloxane (PDMS) micropillars on HDPE substrates to increase the contact angle of the channel(15).
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.
"Cut-and-paste" manufacture of multiparametric epidermal electronic systems
NASA Astrophysics Data System (ADS)
Lu, Nanshu; Yang, Shixuan; Wang, Pulin
2016-05-01
Epidermal electronics is a class of noninvasive and unobstructive skin-mounted, tattoo-like sensors and electronics capable of vital sign monitoring and establishing human-machine interface. The high cost of manpower, materials, vacuum equipment, and photolithographic facilities associated with its manufacture greatly hinders the widespread use of disposable epidermal electronics. Here we report a cost and time effective, completely dry, benchtop "cut-and-paste" method for the freeform and portable manufacture of multiparametric epidermal sensor systems (ESS) within minutes. This versatile method works for all types of thin metal and polymeric sheets and is compatible with any tattoo adhesives or medical tapes. The resulting ESS are multimaterial and multifunctional and have been demonstrated to noninvasively but accurately measure electrophysiological signals, skin temperature, skin hydration, as well as respiratory rate. In addition, planar stretchable coils exploiting double-stranded serpentine design have been successfully applied as wireless, passive epidermal strain sensors.
Split-ball resonator as a three-dimensional analogue of planar split-rings
NASA Astrophysics Data System (ADS)
Kuznetsov, Arseniy I.; Miroshnichenko, Andrey E.; Hsing Fu, Yuan; Viswanathan, Vignesh; Rahmani, Mohsen; Valuckas, Vytautas; Ying Pan, Zhen; Kivshar, Yuri; Pickard, Daniel S.; Luk'Yanchuk, Boris
2014-01-01
Split-ring resonators are basic elements of metamaterials, which can induce a magnetic response in metallic nanosctructures. Tunability of such response up to the visible frequency range is still a challenge. Here we introduce the concept of the split-ball resonator and demonstrate the strong magnetic response in the visible for both gold and silver spherical plasmonic nanoparticles with nanometre scale cuts. We realize this concept experimentally by employing the laser-induced transfer method to produce near-perfect metallic spheres and helium ion beam milling to make cuts with the clean straight sidewalls and nanometre resolution. The magnetic resonance is observed at 600 nm in gold and at 565 nm in silver nanoparticles. This method can be applied to the structuring of arbitrary three-dimensional features on the surface of nanoscale resonators. It provides new ways for engineering hybrid resonant modes and ultra-high near-field enhancement.
Cutting Force Predication Based on Integration of Symmetric Fuzzy Number and Finite Element Method
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
Machine-learning identification of galaxies in the WISE × SuperCOSMOS all-sky catalogue
NASA Astrophysics Data System (ADS)
Krakowski, T.; Małek, K.; Bilicki, M.; Pollo, A.; Kurcz, A.; Krupa, M.
2016-11-01
Context. The two currently largest all-sky photometric datasets, WISE and SuperCOSMOS, have been recently cross-matched to construct a novel photometric redshift catalogue on 70% of the sky. Galaxies were separated from stars and quasars through colour cuts, which may leave imperfections because different source types may overlap in colour space. Aims: The aim of the present work is to identify galaxies in the WISE × SuperCOSMOS catalogue through an alternative approach of machine learning. This allows us to define more complex separations in the multi-colour space than is possible with simple colour cuts, and should provide a more reliable source classification. Methods: For the automatised classification we used the support vector machines (SVM) learning algorithm and employed SDSS spectroscopic sources that we cross-matched with WISE × SuperCOSMOS to construct the training and verification set. We performed a number of tests to examine the behaviour of the classifier (completeness, purity, and accuracy) as a function of source apparent magnitude and Galactic latitude. We then applied the classifier to the full-sky data and analysed the resulting catalogue of candidate galaxies. We also compared the resulting dataset with the one obtained through colour cuts. Results: The tests indicate very high accuracy, completeness, and purity (>95%) of the classifier at the bright end; this deteriorates for the faintest sources, but still retains acceptable levels of 85%. No significant variation in the classification quality with Galactic latitude is observed. When we applied the classifier to all-sky WISE × SuperCOSMOS data, we found 15 million galaxies after masking problematic areas. The resulting sample is purer than the one produced by applying colour cuts, at the price of a lower completeness across the sky. Conclusions: The automatic classification is a successful alternative approach to colour cuts for defining a reliable galaxy sample. The identifications we obtained are included in the public release of the WISE × SuperCOSMOS galaxy catalogue. The public release of the WISE × SuperCOSMOS galaxy catalogue is available from http://ssa.roe.ac.uk/WISExSCOS
NASA Astrophysics Data System (ADS)
Yahyaei, Mohsen; Bashiri, Mahdi
2017-12-01
The hub location problem arises in a variety of domains such as transportation and telecommunication systems. In many real-world situations, hub facilities are subject to disruption. This paper deals with the multiple allocation hub location problem in the presence of facilities failure. To model the problem, a two-stage stochastic formulation is developed. In the proposed model, the number of scenarios grows exponentially with the number of facilities. To alleviate this issue, two approaches are applied simultaneously. The first approach is to apply sample average approximation to approximate the two stochastic problem via sampling. Then, by applying the multiple cuts Benders decomposition approach, computational performance is enhanced. Numerical studies show the effective performance of the SAA in terms of optimality gap for small problem instances with numerous scenarios. Moreover, performance of multi-cut Benders decomposition is assessed through comparison with the classic version and the computational results reveal the superiority of the multi-cut approach regarding the computational time and number of iterations.
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.
Cornelissen, M; Salmon, P M; Stanton, N A; McClure, R
2015-01-01
While a safe systems approach has long been acknowledged as the underlying philosophy of contemporary road safety strategies, systemic applications are sparse. This article argues that systems-based methods from the discipline of Ergonomics have a key role to play in road transport design and evaluation. To demonstrate, the Cognitive Work Analysis framework was used to evaluate two road designs - a traditional Melbourne intersection and a cut-through design for future intersections based on road safety safe systems principles. The results demonstrate that, although the cut-through intersection appears different in layout from the traditional intersection, system constraints are not markedly different. Furthermore, the analyses demonstrated that redistribution of constraints in the cut-through intersection resulted in emergent behaviour, which was not anticipated and could prove problematic. Further, based on the lack of understanding of emergent behaviour, similar design induced problems are apparent across both intersections. Specifically, incompatibilities between infrastructure, vehicles and different road users were not dealt with by the proposed design changes. The importance of applying systems methods in the design and evaluation of road transport systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Long, Zhen; Zhang, Yanhai; Gamache, Paul; Guo, Zhimou; Steiner, Frank; Du, Nana; Liu, Xiaoda; Jin, Yan; Liu, Xingguo; Liu, Lvye
2018-01-01
Current Chinese Pharmacopoeia (ChP) standards apply liquid extraction combined with one dimensional liquid chromatography (1DLC) method for determining alkaloids in herbal medicines. The complex pretreatments lead to a low analytical efficiency and possible component loss. In this study, a heart cutting reversed phase - strong cation exchange two dimensional liquid chromatography (RP - SCX 2DLC) approach was optimized for simultaneously quantifying tropane alkaloids (anisodine, scopolamine and hyoscyamine) in herbal medicines and herbal medicine tablets without further treatment of the filtered extract. The chromatographic conditions were systematically optimized in terms of column type, mobile phase composition and flow rate. To improve peak capacity and obtain symmetric peak shape of alkaloids, a polar group embedded C18 column combined with chaotropic salts was used in the first dimension. To remove the disturbance of non-alkaloids, achieve unique selectivity and acquire symmetric peak shape of alkaloids, an SCX column combined with phosphate buffer was used in the second dimension. Method validation was performed in terms of linearity, precision (0.54-0.82%), recovery (94.1-105.2%), limit of detection (LOD) and limit of quantification (LOQ) of the three analytes varied between 0.067-0.115mgL -1 and 0.195-0.268mgL -1 , respectively. The method demonstrated superiority over 1DLC method in respect of resolution (less alkaloid co-eluted), sample preparation (no pretreatment procedure) and transfer rate (minimum component loss). The optimized RP - SCX 2DLC approach was subsequently applied to quantify target alkaloids in five herbal medicines and herbal medicine tablets from three different manufactures. The results demonstrated that the developed heart cutting RP - SCX 2DLC approach represented a new, strategically significant methodology for the quality evaluation of tropane alkaloid in related herbal medicines that involve complex chemical matrix. Copyright © 2017. Published by Elsevier B.V.
Davis, Richard F.; Kemerait, Robert C.
2010-01-01
The southern root-knot nematode (Meloidogyne incognita) is a major parasite of cotton in the U.S., and management tactics for this nematode attempt to minimize population levels. We compared three post-harvest practices for their ability to reduce nematode population levels in the field, thereby reducing initial nematode population for the next year's crop. The three practices tested were: 1) chemical defoliation before harvest plus cutting cotton stalks after harvest, 2) chemical defoliation plus applying a herbicide to kill plants prior to cutting the stalks, and 3) chemical defoliation without cutting stalks. Experiments were conducted in both the greenhouse and in the field. The greenhouse experiments demonstrated that M. incognita reproduction (measured as egg counts and root gall rating indices) was significantly greater when stalks were not cut. Cutting stalks plus applying herbicide to kill cotton roots did not significantly reduce nematode reproduction compared to cutting stalks alone. In field experiments, cutting stalks reduced egg populations and root galling compared to defoliation without stalk cutting. In a greenhouse bioassay which used soil from the field plots, plants grown in soil from the defoliation only treatment had greater root gall ratings and egg counts than in the stalk cutting plus herbicide treatment. Therefore, we conclude that cutting cotton stalks immediately after harvest effectively reduces M. incognita reproduction, and may lead to a lower initial population density of this nematode in the following year. PMID:22736845
Cutting thread at flexible endoscopy.
Gong, F; Swain, P; Kadirkamanathan, S; Hepworth, C; Laufer, J; Shelton, J; Mills, T
1996-12-01
New thread-cutting techniques were developed for use at flexible endoscopy. A guillotine was designed to follow and cut thread at the endoscope tip. A new method was developed for guiding suture cutters. Efficacy of Nd: YAG laser cutting of threads was studied. Experimental and clinical experience with thread-cutting methods is presented. A 2.4 mm diameter flexible thread-cutting guillotine was constructed featuring two lateral holes with sharp edges through which sutures to be cut are passed. Standard suture cutters were guided by backloading thread through the cutters extracorporeally. A snare cutter was constructed to retrieve objects sewn to tissue. Efficacy and speed of Nd: YAG laser in cutting twelve different threads were studied. The guillotine cut thread faster (p < 0.05) than standard suture cutters. Backloading thread shortened time taken to cut thread (p < 0.001) compared with free-hand cutting. Nd: YAG laser was ineffective in cutting uncolored threads and slower than mechanical cutters. Results of thread cutting in clinical studies using sewing machine (n = 77 cutting episodes in 21 patients), in-vivo experiments (n = 156), and postsurgical cases (n = 15 over 15 years) are presented. New thread-cutting methods are described and their efficacy demonstrated in experimental and clinical studies.
Mori, N; Pozzebon, A; Duso, C; Reggiani, N; Pavan, F
2016-02-01
Stinging nettle (Urtica dioica L.) is the most important host plant for both phytoplasma associated with Bois noir disease of the grapevine and its vector Hyalesthes obsoletus Signoret (Hemiptera: Cixiidae). Vector abundance in vineyards is favored by stinging nettle growing in surrounding areas. Nettle control by herbicides or cutting can reduce vector population in vineyards. However, chemical weeding can cause environmental problems. Many authors suggest that stinging nettle control applied during H. obsoletus flight could force adults to migrate into vineyards. We evaluate if cutting of nettle growing along ditches during adult flight favors vineyard colonization by H. obsoletus. Three different weed management regimes ("no cuts," "one cut" just before the beginning of adult flight, and "frequent cuts" over the whole vegetative season) were applied to the herbaceous vegetation in ditches bordering two vineyards. The flight dynamics of H. obsoletus were recorded by placing yellow sticky traps on the vegetation along the ditches and at different positions in the vineyards. Frequent stinging nettle cuts (compared with a single cut) in surrounding areas favored the dispersion of vectors inside the vineyards. Stinging nettle control should be based on an integration of a single herbicide application before H. obsoletus emergence followed by frequent cuts to minimize negative side effects of chemical weeding. In organic viticulture, a frequent-cuts strategy should avoid cuts during H. obsoletus flight period, at least in the first year of adoption. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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.
A review of virtual cutting methods and technology in deformable objects.
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.
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.
Using appropriate body mass index cut points for overweight and obesity among Asian Americans
Jih, Jane; Mukherjea, Arnab; Vittinghoff, Eric; Nguyen, Tung T.; Tsoh, Janice Y.; Fukuoka, Yoshimi; Bender, Melinda S.; Tseng, Winston; Kanaya, Alka M.
2014-01-01
Objective Asian Americans have low prevalence of overweight/obesity based on standard BMI cut points yet have higher rates of diabetes. We examined the prevalence of overweight/obesity, using lower BMI cut points recommended by the World Health Organization (WHO) for Asians, and diabetes in Asian American subgroups in California. Method Secondary analysis of the 2009 adult California Health Interview Survey (n = 45,946) of non-Hispanic Whites (NHW), African Americans, Hispanics and Asians (Vietnamese, Chinese, Korean, Filipino, South Asian and Japanese). WHO Asian BMI cut points (overweight = 23–27.5 kg/m2; obese ≥ 27.5 kg/m2) were used for Asian subgroups. Standard BMI cut points (overweight = 25–29.9 kg/m2; obese ≥ 30 kg/m2) were applied for other groups. Results Among Asian subgroups, overweight/obesity was highest among Filipinos (78.6%), which was higher than NHWs (p < 0.001) but similar to African Americans and Hispanics. Compared to NHW, diabetes prevalence was higher for Vietnamese, Koreans, Filipinos and South Asians with BMI = 23–24.9 kg/m2 and Koreans, Filipinos and Japanese with BMI = 27.5–29.9 kg/m2, the ranges WHO recommends as overweight or obese for Asians but not for other groups. Conclusions Filipinos should be a priority population for overweight/obesity screening. Filipinos, Vietnamese, Korean, South Asians and Japanese have higher diabetes prevalence at lower BMI cut points. WHO Asian BMI cut points may have clinical utility to identify at-risk Asian Americans. PMID:24736092
Computation of two-dimensional flows past ram-air parachutes
NASA Astrophysics Data System (ADS)
Mittal, S.; Saxena, P.; Singh, A.
2001-03-01
Computational results for flow past a two-dimensional model of a ram-air parachute with leading edge cut are presented. Both laminar (Re=104) and turbulent (Re=106) flows are computed. A well-proven stabilized finite element method (FEM), which has been applied to various flow problems earlier, is utilized to solve the incompressible Navier-Stokes equations in the primitive variables formulation. The Baldwin-Lomax model is employed for turbulence closure. Turbulent flow computations past a Clarck-Y airfoil without a leading edge cut, for =7.5°, result in an attached flow. The leading edge cut causes the flow to become unsteady and leads to a significant loss in lift and an increase in drag. The flow inside the parafoil cell remains almost stagnant, resulting in a high value of pressure, which is responsible for giving the parafoil its shape. The value of the lift-to-drag ratio obtained with the present computations is in good agreement with those reported in the literature. The effect of the size and location of the leading edge cut is studied. It is found that the flow on the upper surface of the parafoil is fairly insensitive to the configuration of the cut. However, the flow quality on the lower surface improves as the leading edge cut becomes smaller. The lift-to-drag ratio for various configurations of the leading edge cut varies between 3.4 and 5.8. It is observed that even though the time histories of the aerodynamic coefficients from the laminar and turbulent flow computations are quite different, their time-averaged values are quite similar. Copyright
“Agility” - Complexity Description in a New Dimension applied for Laser Cutting
NASA Astrophysics Data System (ADS)
Bartels, F.; Suess, B.; Wagner, A.; Hauptmann, J.; Wetzig, A.; Beyer, E.
How to describe or to compare the complexity of industrial upcoming part geometries in laser-cutting? This question is essential for defining machine dynamics or kinematic structures for efficient use of the technological cutting-potential which is given by modern beam sources. Solid-state lasers as well as CO2 lasers offer, especially in thin materials, the opportunity of high cutting velocities. Considering the mean velocity on cutting geometries, it is significantly below the technological limitations. The characterization of cutting geometries by means of the agility as well as the application for laser-cutting will be introduced. The identification of efficient dynamic constellations will be shown as basic principle for designing future machine structures.
... will be applying the patch. Cut open the envelope containing the patches, cutting on the dotted line ... it. Pull apart the zipper seal on the envelope and remove one patch. Reseal the envelope by ...
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...
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.
Ivanov, Ilia N [Knoxville, TN; Simpson, John T [Clinton, IN
2012-01-24
A method of making a large area conformable shape structure comprises drawing a plurality of tubes to form a plurality of drawn tubes, and cutting the plurality of drawn tubes into cut drawn tubes of a predetermined shape. The cut drawn tubes have a first end and a second end along the longitudinal direction of the cut drawn tubes. The method further comprises conforming the first end of the cut drawn tubes into a predetermined curve to form the large area conformable shape structure, wherein the cut drawn tubes contain a material.
Ercoli, Carlo; Rotella, Mario; Funkenbusch, Paul D; Russell, Scott; Feng, Changyong
2009-05-01
The cutting behavior of dental rotary cutting instruments is influenced by the handpiece used. While the turbine handpiece has been extensively tested in previous studies, limited published information exists on the use of rotary cutting instruments with the electric handpiece system and on possible interactions between rotary cutting instruments and handpiece type. The purpose of this study was to examine the cutting performance of a wide selection of rotary cutting instruments tested with the electric handpiece and compare the results with those of the air-turbine handpiece (Part I), identifying possible interactions between handpiece type and rotary cutting instruments. Ten groups of rotary cutting instruments (n=30) designed for tooth preparation were selected: 9 diamond (7 multi-use, 2 disposable) and 1 carbide. Macor blocks (n=75) were used as a substrate, and 4 cuts were made on each specimen, using a new rotary cutting instrument each time, for a total of 300 cuts. The cuts were performed with an electric handpiece (Intramatic Lux K200), with the same methods used in the Part I study. To qualitatively evaluate the rotary cutting instrument surface characteristics, 1 specimen from each group was examined 3 times with a scanning electron microscope (SEM): before use, then after use, but before being cleaned and sterilized, and finally, after ultrasonic cleaning. To compare rotary cutting instrument performance between the turbine and electric handpieces, the data were analyzed using 2-way ANOVA to study the main effects of the group of rotary cutting instruments, handpieces, and their interaction. For analysis of the significant main effect, 1-way ANOVA and Tukey's Studentized Range test were used (alpha=.05). Compared to the baseline temperature, all rotary cutting instruments showed a reduction of the temperature in the simulated pulp chamber when tested with the electric handpiece. The Great White Ultra (carbide bur) showed the highest rate of advancement (0.17 mm/s) and lowest applied load (108.35 g). Considering all rotary cutting instruments as a single group, the electric handpiece showed mean lower temperature (26.68 degrees C), higher rate of advancement (0.12 mm/s), and higher load (124.53 g) than the air-turbine handpiece (28.37 degrees C, 0.11 mm/s, and 121.7 g, respectively). Considering each single group of rotary cutting instruments, significant differences were found for the electric or air-turbine handpiece. The tested carbide bur showed greater cutting efficiency than the tested diamond rotary cutting instruments when used with the electric handpiece. The electric handpiece showed a higher cutting efficiency than the turbine, especially when used with the carbide bur, probably due to its greater torque.
Selecting a silvicultural system
Richard M. Godman
1992-01-01
Sometimes a name creates a problem. The name of a silvicultural system usually refers to the way a stand is cut to get regeneration-"single tree selection"-for example. Trouble is, the name suggests that the regeneration cut will be the first treatment applied to the stand. Not so. We are now mostly making "intermediate" cuts in our Lake States...
Abdeldaim, G; Herrmann, B; Korsgaard, J; Olcén, P; Blomberg, J; Strålin, K
2009-06-01
The pneumolysin (ply) gene is widely used as a target in PCR assays for Streptococcus pneumoniae in respiratory secretions. However, false-positive results with conventional ply-based PCR have been reported. The aim here was to study the performance of a quantitative ply-based PCR for the identification of pneumococcal lower respiratory tract infection (LRTI). In a prospective study, fibreoptic bronchoscopy was performed in 156 hospitalized adult patients with LRTI and 31 controls who underwent bronchoscopy because of suspicion of malignancy. Among the LRTI patients and controls, the quantitative ply-based PCR applied to bronchoalveolar lavage (BAL) fluid was positive at >or=10(3) genome copies/mL in 61% and 71% of the subjects, at >or=10(5) genome copies/mL in 40% and 58% of the subjects, and at >or=10(7) genome copies/mL in 15% and 3.2% of the subjects, respectively. Using BAL fluid culture, blood culture, and/or a urinary antigen test, S. pneumoniae was identified in 19 LRTI patients. As compared with these diagnostic methods used in combination, quantitative ply-based PCR showed sensitivities and specificities of 89% and 43% at a cut-off of 10(3) genome copies/mL, of 84% and 66% at a cut-off of 10(5) genome copies/mL, and of 53% and 90% at a cut-off of 10(7) genome copies/mL, respectively. In conclusion, a high cut-off with the quantitative ply-based PCR was required to reach acceptable specificity. However, as a high cut-off resulted in low sensitivity, quantitative ply-based PCR does not appear to be clinically useful. Quantitative PCR methods for S. pneumoniae using alternative gene targets should be evaluated.
INTERIOR VIEW SHOWING PROTOTYPE BEGUN APRIL 1988 METHOD OF CUTTING ...
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
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.
Assessment of commuters' daily exposure to flash flooding over the roads of the Gard region, France
NASA Astrophysics Data System (ADS)
Debionne, Samuel; Ruin, Isabelle; Shabou, Saif; Lutoff, Céline; Creutin, Jean-Dominique
2016-10-01
Flash floods are responsible for a majority of natural disaster fatalities in the USA and Europe and most of them are vehicle-related. If human exposure to flood is generally assessed through the number of inhabitants per buildings located in flood prone zone, it is clear that this number varies dramatically throughout the day as people move from place to place to follow their daily program of activities. Knowing the number of motorists exposed on flood prone road sections or the factors determining their exposure would allow providing a more realistic evaluation of the degree of exposure. In order to bridge this gap and provide emergency managers with methods to assess the risk level for motorists, this paper describes two methods, a simple rough-and-ready estimate and a traffic attribution method, and applies both of them on datasets of the Gard département, an administrative region of Southern France with about 700 000 inhabitants over 5875 km2. The first method to obtain an overall estimation of motorists flood exposure is to combine (i) the regional density of roads and rivers to derive a count of potential road cuts and (ii) the average daily kilometers driven by commuters of the study area to derive the number of people passing these potential cuts. If useful as a first approximation, this method fails to capture the spatial heterogeneities introduced by the geometry of river and road networks and the distribution of commuters' itineraries. To address this point, this paper (i) uses a pre-established detailed identification of road cuts (Naulin et al., 2013) and (ii) applies a well-known traffic attribution method to existing and freely available census datasets. Both methods indicate that commuters' exposure is much larger than the number of commuters itself, illustrating the risk amplification effect of mobility. Comparing the results from both methods shows that (i) the road network geometry plays a significant role in reducing the risk of river-road dangerous intersections and (ii) not all commuters are equally exposed. Evidently commuters who have longer routes are more exposed, but residents of rural municipalities as well as professionals with highly qualified jobs are also more exposed. Finally, these exposure assessment methods applied to the Gard area allows locating road sections where commuters' exposure to flood is high. It also sets the first step toward the implementation of a modeling platform able to combine the estimation of daily travel patterns exposure and behavioral response of motorists to road flooding, a critical input for emergency services and services in charge of the management of road networks in flash flood prone areas.
Factor models for cancer signatures
NASA Astrophysics Data System (ADS)
Kakushadze, Zura; Yu, Willie
2016-11-01
We present a novel method for extracting cancer signatures by applying statistical risk models (http://ssrn.com/abstract=2732453) from quantitative finance to cancer genome data. Using 1389 whole genome sequenced samples from 14 cancers, we identify an ;overall; mode of somatic mutational noise. We give a prescription for factoring out this noise and source code for fixing the number of signatures. We apply nonnegative matrix factorization (NMF) to genome data aggregated by cancer subtype and filtered using our method. The resultant signatures have substantially lower variability than those from unfiltered data. Also, the computational cost of signature extraction is cut by about a factor of 10. We find 3 novel cancer signatures, including a liver cancer dominant signature (96% contribution) and a renal cell carcinoma signature (70% contribution). Our method accelerates finding new cancer signatures and improves their overall stability. Reciprocally, the methods for extracting cancer signatures could have interesting applications in quantitative finance.
Tanner, Hannah; Evans, Jason T; Gossain, Savita; Hussain, Abid
2017-01-18
Patient mortality is significantly reduced by rapid identification of bacteria from sterile sites. MALDI-TOF can identify bacteria directly from positive blood cultures and multiple sample preparation methods are available. We evaluated three sample preparation methods and two MALDI-TOF score cut-off values. Positive blood culture bottles with organisms present in Gram stains were prospectively analysed by MALDI-TOF. Three lysis reagents (Saponin, SDS, and SepsiTyper lysis bufer) were applied to each positive culture followed by centrifugation, washing and protein extraction steps. Methods were compared using the McNemar test and 16S rDNA sequencing was used to assess discordant results. In 144 monomicrobial cultures, using ≥2.000 as the cut-off value, species level identifications were obtained from 69/144 (48%) samples using Saponin, 86/144 (60%) using SDS, and 91/144 (63%) using SepsiTyper. The difference between SDS and SepsiTyper was not statistically significant (P = 0.228). Differences between Saponin and the other two reagents were significant (P < 0.01). Using ≥1.700 plus top three results matching as the cut-off value, species level identifications were obtained from 100/144 (69%) samples using Saponin, 103/144 (72%) using SDS, and 106/144 (74%) using SepsiTyper and there was no statistical difference between the methods. No true discordances between culture and direct MALDI-TOF identification were observed in monomicrobial cultures. In 32 polymicrobial cultures, MALDI-TOF identified one organism in 34-75% of samples depending on the method. This study demonstrates two inexpensive in-house detergent lysis methods are non-inferior to a commercial kit for analysis of positive blood cultures by direct MALDI-TOF in a clinical diagnostic microbiology laboratory.
Celik, Talip; Mutlu, Ibrahim; Ozkan, Arif; Kisioglu, Yasin
2016-01-01
Background. In this study, the cut-out risk of Dynamic Hip Screw (DHS) was investigated in nine different positions of the lag screw for two fracture types by using Finite Element Analysis (FEA). Methods. Two types of fractures (31-A1.1 and A2.1 in AO classification) were generated in the femur model obtained from Computerized Tomography images. The DHS model was placed into the fractured femur model in nine different positions. Tip-Apex Distances were measured using SolidWorks. In FEA, the force applied to the femoral head was determined according to the maximum value being observed during walking. Results. The highest volume percentage exceeding the yield strength of trabecular bone was obtained in posterior-inferior region in both fracture types. The best placement region for the lag screw was found in the middle of both fracture types. There are compatible results between Tip-Apex Distances and the cut-out risk except for posterior-superior and superior region of 31-A2.1 fracture type. Conclusion. The position of the lag screw affects the risk of cut-out significantly. Also, Tip-Apex Distance is a good predictor of the cut-out risk. All in all, we can supposedly say that the density distribution of the trabecular bone is a more efficient factor compared to the positions of lag screw in the cut-out risk.
A 3D modeling approach to complex faults with multi-source data
NASA Astrophysics Data System (ADS)
Wu, Qiang; Xu, Hua; Zou, Xukai; Lei, Hongzhuan
2015-04-01
Fault modeling is a very important step in making an accurate and reliable 3D geological model. Typical existing methods demand enough fault data to be able to construct complex fault models, however, it is well known that the available fault data are generally sparse and undersampled. In this paper, we propose a workflow of fault modeling, which can integrate multi-source data to construct fault models. For the faults that are not modeled with these data, especially small-scale or approximately parallel with the sections, we propose the fault deduction method to infer the hanging wall and footwall lines after displacement calculation. Moreover, using the fault cutting algorithm can supplement the available fault points on the location where faults cut each other. Increasing fault points in poor sample areas can not only efficiently construct fault models, but also reduce manual intervention. By using a fault-based interpolation and remeshing the horizons, an accurate 3D geological model can be constructed. The method can naturally simulate geological structures no matter whether the available geological data are sufficient or not. A concrete example of using the method in Tangshan, China, shows that the method can be applied to broad and complex geological areas.
Effects of Microwave Radiation on Oil Recovery
NASA Astrophysics Data System (ADS)
Esmaeili, Abdollah
2011-12-01
A variety of oil recovery methods have been developed and applied to mature and depleted reservoirs in order to improve the efficiency. Microwave radiation oil recovery method is a relatively new method and has been of great interest in the recent years. Crude oil is typically co-mingled with suspended solids and water. To increase oil recovery, it is necessary to remove these components. The separation of oil from water and solids using gravitational settling methods is typically incomplete. Oil-in-water and oil-water-solid emulsions can be demulsified and separated into their individual layers by microwave radiation. The data also show that microwave separation is faster than gravity separation and can be faster than conventional heating at many conditions. After separation of emulsion into water and oil layers, water can be discharged and oil is collected. High-frequency microwave recycling process can recover oil and gases from oil shale, residual oil, drill cuttings, tar sands oil, contaminated dredge/sediments, tires and plastics with significantly greater yields and lower costs than are available utilizing existing known technologies. This process is environmentally friendly, fuel-generating recycler to reduce waste, cut emissions, and save energy. This paper presents a critical review of Microwave radiation method for oil recovery.
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
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…
de Oliveira, Ricardo A G; Camargo, Fiamma; Pesquero, Naira C; Faria, Ronaldo Censi
2017-03-08
This paper describes the fabrication of 2D and 3D microfluidic paper-based analytical devices (μPADs) for monitoring glucose, total protein, and nitrite in blood serum and artificial urine. A new method of cutting and sealing filter paper to construct μPADs was demonstrated. Using an inexpensive home cutter printer soft cellulose-based filter paper was easily and precisely cut to produce pattern hydrophilic microchannels. 2D and 3D μPADs were designed with three detection zones each for the colorimetric detection of the analytes. A small volume of samples was added to the μPADs, which was photographed after 15 min using a digital camera. Both μPADs presented an excellent analytical performance for all analytes. The 2D device was applied in artificial urine samples and reached limits of detection (LODs) of 0.54 mM, 5.19 μM, and 2.34 μM for glucose, protein, and nitrite, respectively. The corresponding LODs of the 3D device applied for detecting the same analytes in artificial blood serum were 0.44 mM, 1.26 μM, and 4.35 μM. Copyright © 2017 Elsevier B.V. All rights reserved.
Chatter active control in a lathe machine using magnetostrictive actuator
NASA Astrophysics Data System (ADS)
Nosouhi, R.; Behbahani, S.
2011-01-01
This paper analyzes the chatter phenomena in lathe machines. Chatter is one of the main causes of inaccuracy, reduction of life cycle of the machine and tool wear in machine tools. This phenomenon limits the depth of cut as a function of the cutting speed, which consequently reduces the material removal rate and machining efficiency. Chatter control is therefore important since it increases the stability region in machining and increases the critical depth of cut in machining case. To control the chatter in lathe machines, a magnetostrictive actuator is used. The materials with magnetostriction properties are kind of smart materials of which their length changes as a result of applying an exterior magnetic field, which make them suitable for control applications. It is assumed that the actuator applies the proper force exactly at the point where the machining force is applied on the tool. In this paper the chatter stability lobes is excelled as a result of applying a PID controller on the magnetostrictive actuator equipped-tool in turning.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-10
... (Photographic Film Cutting); Goose Creek, South Carolina The South Carolina State Ports Authority, grantee of... facility is located within Site 16 of FTZ 21. The facility is used for the cutting of photographic film to... choose the duty rates during customs entry procedures that apply to its finished cut film (3.7%) and...
Contact diode laser application through a fiberoptic cutting tip.
Peyman, G A; Cruz, S A; Ruiz-Lapuente, C
1991-01-01
We applied diode laser energy through a fiberoptic probe to cut ocular structures. The diameter of the probe's tip was 100 microns. The amount of energy used for cutting the lid, the cornea, or for perforation of the glove was 2.5 watts in the continuous mode. The incised border demonstrated coagulation into the healthy tissue ranging from 10 to 50 microns.
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.
Castrejón, Isabel; Ortiz, Ana M.; Toledano, Esther; Castañeda, Santos; García-Vadillo, Alberto; Carmona, Loreto
2016-01-01
Objective To estimate cut-off points and to establish response criteria for the Hospital Universitario La Princesa Index (HUPI) in patients with chronic polyarthritis. Methods Two cohorts, one of early arthritis (Princesa Early Arthritis Register Longitudinal [PEARL] study) and other of long-term rheumatoid arthritis (Estudio de la Morbilidad y Expresión Clínica de la Artritis Reumatoide [EMECAR]) including altogether 1200 patients were used to determine cut-off values for remission, and for low, moderate and high activity through receiver operating curve (ROC) analysis. The areas under ROC (AUC) were compared to those of validated indexes (SDAI, CDAI, DAS28). ROC analysis was also applied to establish minimal and relevant clinical improvement for HUPI. Results The best cut-off points for HUPI are 2, 5 and 9, classifying RA activity as remission if ≤2, low disease activity if >2 and ≤5), moderate if >5 and <9 and high if ≥9. HUPI’s AUC to discriminate between low-moderate activity was 0.909 and between moderate-high activity 0.887. DAS28’s AUCs were 0.887 and 0.846, respectively; both indices had higher accuracy than SDAI (AUCs: 0.832 and 0.756) and CDAI (AUCs: 0.789 and 0.728). HUPI discriminates remission better than DAS28-ESR in early arthritis, but similarly to SDAI. The HUPI cut-off for minimal clinical improvement was established at 2 and for relevant clinical improvement at 4. Response criteria were established based on these cut-off values. Conclusions The cut-offs proposed for HUPI perform adequately in patients with either early or long term arthritis. PMID:27603313
1994-05-01
utilizes drill bits and tubing to cut through the soil. Unlike the auger method, a slurry mixture is used to keep the drill bit clean and assist in...is applied. In the sleeve pipe method, or also called tube -a-manchette, the sleeve pipe is installed in the grout hole, and sealed in place with a...acts as a one-way valve. allowing grout out of the pipe, but not back into the sleeve. A grouting tube with double packer is used to inject the grout
Study on Roadheader Cutting Load at Different Properties of Coal and Rock
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
Southern Pine Beetle Survival In Trees Felled By the Cut and Top-Cut and Leave Method
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...
Automatic building extraction from LiDAR data fusion of point and grid-based features
NASA Astrophysics Data System (ADS)
Du, Shouji; Zhang, Yunsheng; Zou, Zhengrong; Xu, Shenghua; He, Xue; Chen, Siyang
2017-08-01
This paper proposes a method for extracting buildings from LiDAR point cloud data by combining point-based and grid-based features. To accurately discriminate buildings from vegetation, a point feature based on the variance of normal vectors is proposed. For a robust building extraction, a graph cuts algorithm is employed to combine the used features and consider the neighbor contexture information. As grid feature computing and a graph cuts algorithm are performed on a grid structure, a feature-retained DSM interpolation method is proposed in this paper. The proposed method is validated by the benchmark ISPRS Test Project on Urban Classification and 3D Building Reconstruction and compared to the state-art-of-the methods. The evaluation shows that the proposed method can obtain a promising result both at area-level and at object-level. The method is further applied to the entire ISPRS dataset and to a real dataset of the Wuhan City. The results show a completeness of 94.9% and a correctness of 92.2% at the per-area level for the former dataset and a completeness of 94.4% and a correctness of 95.8% for the latter one. The proposed method has a good potential for large-size LiDAR data.
The efficacy of disinfectants on abattoirs’ Candida albicans isolates in Niger Delta region
Olorode, Oluwayemisi A
2012-01-01
This study was conducted to evaluate the antimicrobial activities of common disinfectants- these are (parachlorometaxylenol) dettol, savlon purit and jik (sodium hypochlorite) on Candida albicans isolated from displaying and cutting tables in five different abattoirs in Port Harcourt (Niger Delta region); the abattoirs include Trans Amadi, Agip, Woji, Rumuokoro, and Rumuodara. This research was carried out between January 2005 and June 2006. Swab samples were collected from abattoirs cutting tables with sterile swab sticks and immediately transferred and cultured in the laboratory on a selective medium Sabouraud Dextrose Agar (SDA). The disinfectants’ concentrations were prepared at 10%, 20%, 40%, and 70%, in triplicates and the mean values calculated. 0.5 Mc Farland turbidity method of standardization and Agar diffusion method were used for disinfectants testing of the isolates. Statistical analysis of the data showed no significant difference in the effectiveness of these disinfectants at (p<0.05). In conclusion, this study has shown that savlon and dettol were the most potent antimicrobial agents at 10% concentration on Candida albicans isolates when compared with purit and jik in this study, hence they are good sanitizing agents to be applied on the abattoirs cutting tables, before meat products can be displayed for sale. PMID:24358834
NASA Astrophysics Data System (ADS)
Druart, Guillaume; Rommeluere, Sylvain; Viale, Thibault; Guerineau, Nicolas; Ribet-Mohamed, Isabelle; Crastes, Arnaud; Durand, Alain; Taboury, Jean
2014-05-01
Today, both military and civilian applications require miniaturized and cheap optical systems. One way to achieve this trend consists in decreasing the pixel pitch of focal plane arrays (FPA). In order to evaluate the performance of the overall optical systems, it is necessary to measure the modulation transfer function (MTF) of these pixels. However, small pixels lead to higher cut-off frequencies and therefore, original MTF measurements that are able to extract frequencies up to these high cut-off frequencies, are needed. In this paper, we will present a way to extract 1D MTF at high frequencies by projecting fringes on the FPA. The device uses a Lloyd mirror placed near and perpendicular to the focal plane array. Consequently, an interference pattern of fringes can be projected on the detector. By varying the angle of incidence of the light beam, we can tune the period of the interference fringes and, thus, explore a wide range of spatial frequencies, and mainly around the cut-off frequency of the pixel which is one of the most interesting area. Illustration of this method will be applied to a 640×480 microbolometer focal plane array with a pixel pitch of 17µm in the LWIR spectral region.
Chien, Chia-Chang; Huang, Shu-Fen; Lung, For-Wey
2009-01-01
Objective: The purpose of this study was to apply a two-stage screening method for the large-scale intelligence screening of military conscripts. Methods: We collected 99 conscripted soldiers whose educational levels were senior high school level or lower to be the participants. Every participant was required to take the Wisconsin Card Sorting Test (WCST) and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) assessments. Results: Logistic regression analysis showed the conceptual level responses (CLR) index of the WCST was the most significant index for determining intellectual disability (ID; FIQ ≤ 84). We used the receiver operating characteristic curve to determine the optimum cut-off point of CLR. The optimum one cut-off point of CLR was 66; the two cut-off points were 49 and 66. Comparing the two-stage window screening with the two-stage positive screening, the area under the curve and the positive predictive value increased. Moreover, the cost of the two-stage window screening decreased by 59%. Conclusion: The two-stage window screening is more accurate and economical than the two-stage positive screening. Our results provide an example for the use of two-stage screening and the possibility of the WCST to replace WAIS-R in large-scale screenings for ID in the future. PMID:21197345
Energy saving in ac generators
NASA Technical Reports Server (NTRS)
Nola, F. J.
1980-01-01
Circuit cuts no-load losses, without sacrificing full-load power. Phase-contro circuit includes gate-controlled semiconductor switch that cuts off applied voltage for most of ac cycle if generator idling. Switch "on" time increases when generator is in operation.
Calibration and comparison of accelerometer cut points in preschool children.
van Cauwenberghe, Eveline; Labarque, Valery; Trost, Stewart G; de Bourdeaudhuij, Ilse; Cardon, Greet
2011-06-01
The present study aimed to develop accelerometer cut points to classify physical activities (PA) by intensity in preschoolers and to investigate discrepancies in PA levels when applying various accelerometer cut points. To calibrate the accelerometer, 18 preschoolers (5.8 ± 0.4 years) performed eleven structured activities and one free play session while wearing a GT1M ActiGraph accelerometer using 15 s epochs. The structured activities were chosen based on the direct observation system Children's Activity Rating Scale (CARS) while the criterion measure of PA intensity during free play was provided using a second-by-second observation protocol (modified CARS). Receiver Operating Characteristic (ROC) curve analyses were used to determine the accelerometer cut points. To examine the classification differences, accelerometer data of four consecutive days from 114 preschoolers (5.5 ± 0.3 years) were classified by intensity according to previously published and the newly developed accelerometer cut points. Differences in predicted PA levels were evaluated using repeated measures ANOVA and Chi Square test. Cut points were identified at 373 counts/15 s for light (sensitivity: 86%; specificity: 91%; Area under ROC curve: 0.95), 585 counts/15 s for moderate (87%; 82%; 0.91) and 881 counts/15 s for vigorous PA (88%; 91%; 0.94). Further, applying various accelerometer cut points to the same data resulted in statistically and biologically significant differences in PA. Accelerometer cut points were developed with good discriminatory power for differentiating between PA levels in preschoolers and the choice of accelerometer cut points can result in large discrepancies.
Extraction of breast lesions from ultrasound imagery: Bhattacharyya gradient flow approach
NASA Astrophysics Data System (ADS)
Torkaman, Mahsa; Sandhu, Romeil; Tannenbaum, Allen
2018-03-01
Breast cancer is one of the most commonly diagnosed neoplasms among American women and the second leading cause of death among women all over the world. In order to reduce the mortality rate and cost of treatment, early diagnosis and treatment are essential. Accurate and reliable diagnosis is required in order to ensure the most effective treatment and a second opinion is often advisable. In this paper, we address the problem of breast lesion detection from ultrasound imagery by means of active contours, whose evolution is driven by maximizing the Bhattacharyya distance1 between the probability density functions (PDFs). The proposed method was applied to ultrasound breast imagery, and the lesion boundary was obtained by maximizing the distance-based energy functional such that the maximum (optimal contour) is attained at the boundary of the potential lesion. We compared the results of the proposed method quantitatively using the Dice coefficient (similarity index)2 to well-known GrowCut segmentation method3 and demonstrated that Bhattacharyya approach outperforms GrowCut in most of the cases.
Well-balanced compressible cut-cell simulation of atmospheric flow.
Klein, R; Bates, K R; Nikiforakis, N
2009-11-28
Cut-cell meshes present an attractive alternative to terrain-following coordinates for the representation of topography within atmospheric flow simulations, particularly in regions of steep topographic gradients. In this paper, we present an explicit two-dimensional method for the numerical solution on such meshes of atmospheric flow equations including gravitational sources. This method is fully conservative and allows for time steps determined by the regular grid spacing, avoiding potential stability issues due to arbitrarily small boundary cells. We believe that the scheme is unique in that it is developed within a dimensionally split framework, in which each coordinate direction in the flow is solved independently at each time step. Other notable features of the scheme are: (i) its conceptual and practical simplicity, (ii) its flexibility with regard to the one-dimensional flux approximation scheme employed, and (iii) the well-balancing of the gravitational sources allowing for stable simulation of near-hydrostatic flows. The presented method is applied to a selection of test problems including buoyant bubble rise interacting with geometry and lee-wave generation due to topography.
Deducing material quality in cast and hot-forged steels by new bending test
NASA Astrophysics Data System (ADS)
Valberg, Henry; Langøy, Morten; Nedreberg, Mette; Helvig, Torgeir
2017-10-01
A special bend test has been developed and applied for the purpose of characterization and comparison of the material ductility in crankpin steel discs manufactured by casting, or casting subsequently followed by hot open-die forging (ODF) or closed-die forging (CDF). The bending test specimen consists of a small rectangular plate of material with a round hole cut out in the middle. The "eye-shape" specimens were cut out from various positions either near to the surface of, or from the interior of the discs. The test method revealed differences in ductility for the investigated materials, and for different depth positions inside the discs. The roughening of the specimen surface on the top-side of the specimen bend also varied dependent on the processing method for the material. Current results show that this test method is useful for evaluation of material quality in differently processed material. Experimental bend test results are presented for differently processed variants of the same material, i.e., crankpin discs either made by solely casting or casting subsequently followed by hot working either by ODF or CDF.
Applying a crop-tree release in small-sawtimber white oak stands
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...
Emily A. Carter; Robert B. Rummer; Bryce J. Stokes
2006-01-01
Soil disturbance patterns and associated changes in soil physical status were measured in a study that evaluated the implementation of three alternative management prescriptions in an upland hardwood stand in northern Alabama, USA. Management prescriptions applied in this study consisted of a clear-cut, strip cut, and deferment cut that were compared to a non-harvested...
Reduce, Reuse, Recycle: The Longitudinal Value of Local Cut Scores Using State Test Data
ERIC Educational Resources Information Center
Nelson, Peter M.; Van Norman, Ethan R.; VanDerHeyden, Amanda
2017-01-01
We used existing reading (n = 1,498) and math (n = 2,260) data to evaluate state test scores for screening middle school students. In Phase 1, state test data were used to create a research-derived cut score that was optimal for predicting state test performance the following year. In Phase 2, those cut scores were applied with future cohorts.…
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
Means and method for nonuniform poling of piezoelectric transducers
Hsu, David K.; Margetan, Frank J.; Hasselbusch, Michael D.; Wormley, Samuel J.; Hughes, Michael S.; Thompson, Donald O.
1990-10-09
An apparatus and method for nonuniform poling of piezoelectric transducers includes machining one or more indentation into an end of a piezoelectric rod and cutting the rod to present a thickened disk shape. Highly electrically conductive material is deposited on at least the indentations in the one end and on at least portions of the opposite face of the member. One or more electrodes are configured to matingly fit within the indentations on the one face of the disk, with a like number of electrodes being positionable on the opposite face of the material. Electrical power is then applied to the electrodes in desired amounts, polarity, and duration. The indentations vary the electrical field produced within the piezoelectric material to produce nonuniform poling in the material. The thick disk is then cut to remove the indentations and to present a thin, flat two sided disk for installation in a conventional piezoelectric transducer probe. The indentations are selected to produce poling in accordance with desired transducer response profiles such as Gaussian or Bessel functions.
Aspects of the tribological behaviour of powders recycled from rapid steel treated sub-zero
NASA Astrophysics Data System (ADS)
Radu, S.; Ciobanu, M.
2017-02-01
The recycling of high-alloyed steels represents a significant opportunity in Powder Metallurgy as it permits the use of raw materials with relatively low prices compared to the conventional methods. Recycling can be achieved by two methods: from spraying debris resulted from worn cutting tools and processes obtained from processing chip drilling and re-sharpening of tools. The research aims to confirm that wastes from rapid steels can become, by the successive processing, metal powders that can thereafter be used for cutting tools of lathe type removable plate. After pressing and sintering the recycling powder, cylindrical samples were obtained that were subsequently applied a subcritical annealing. Wear tests conducted on a tribometer type TRB-01-02541 confirmed that their wear resistance is superior to the same samples that were sintered, hardened and tempered in oil. This paper was accepted for publication in Proceedings after double peer reviewing process but was not presented at the Conference ROTRIB’16.
NASA Astrophysics Data System (ADS)
Madajewski, Marek; Nowakowski, Zbigniew
2017-01-01
This paper presents analysis of flank wear influence on forces in orthogonal turning of 42CrMo4 steel and evaluates capacity of finite element model to provide such force values. Data about magnitude of feed and cutting force were obtained from measurements with force tensiometer in experimental test as well as from finite element analysis of chip formation process in ABAQUS/Explicit software. For studies an insert with complex rake face was selected and flank wear was simulated by grinding operation on its flank face. The aim of grinding inset surface was to obtain even flat wear along cutting edge, which after the measurement could be modeled with CAD program and applied in FE analysis for selected range of wear width. By comparing both sets of force values as function of flank wear in given cutting conditions FEA model was validated and it was established that it can be applied to analyze other physical aspects of machining. Force analysis found that progression of wear causes increase in cutting force magnitude and steep boost to feed force magnitude. Analysis of Fc/Ff force ratio revealed that flank wear has significant impact on resultant force in orthogonal cutting and magnitude of this force components in cutting and feed direction. Surge in force values can result in transfer of substantial loads to machine-tool interface.
Flux cutting in high- T c superconductors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vlasko-Vlasov, V.; Koshelev, A.; Glatz, A.
We performed magneto-optical study of flux distributions in a YBCO crystal under various applied crossed- field orientations to elucidate the complex nature of magnetic flux cutting in superconductors. Our study reveals unusual vortex patterns induced by the interplay between flux-cutting and vortex pinning. We observe strong flux penetration anisotropy of the normal flux B⊥ in the presence of an in-plane field H|| and associate the modified flux dynamics with staircase structure of tilted vortices in YBCO and the flux-cutting process. We demonstrate that flux-cutting can effectively delay vortex entry in the direction transverse to H||. Finally, we elucidate details ofmore » the vortex-cutting and reconnection process using time-dependent Ginzburg-Landau simulations.« less
Hard-Rock Stability Analysis for Span Design in Entry-Type Excavations with Learning Classifiers
García-Gonzalo, Esperanza; Fernández-Muñiz, Zulima; García Nieto, Paulino José; Bernardo Sánchez, Antonio; Menéndez Fernández, Marta
2016-01-01
The mining industry relies heavily on empirical analysis for design and prediction. An empirical design method, called the critical span graph, was developed specifically for rock stability analysis in entry-type excavations, based on an extensive case-history database of cut and fill mining in Canada. This empirical span design chart plots the critical span against rock mass rating for the observed case histories and has been accepted by many mining operations for the initial span design of cut and fill stopes. Different types of analysis have been used to classify the observed cases into stable, potentially unstable and unstable groups. The main purpose of this paper is to present a new method for defining rock stability areas of the critical span graph, which applies machine learning classifiers (support vector machine and extreme learning machine). The results show a reasonable correlation with previous guidelines. These machine learning methods are good tools for developing empirical methods, since they make no assumptions about the regression function. With this software, it is easy to add new field observations to a previous database, improving prediction output with the addition of data that consider the local conditions for each mine. PMID:28773653
Hard-Rock Stability Analysis for Span Design in Entry-Type Excavations with Learning Classifiers.
García-Gonzalo, Esperanza; Fernández-Muñiz, Zulima; García Nieto, Paulino José; Bernardo Sánchez, Antonio; Menéndez Fernández, Marta
2016-06-29
The mining industry relies heavily on empirical analysis for design and prediction. An empirical design method, called the critical span graph, was developed specifically for rock stability analysis in entry-type excavations, based on an extensive case-history database of cut and fill mining in Canada. This empirical span design chart plots the critical span against rock mass rating for the observed case histories and has been accepted by many mining operations for the initial span design of cut and fill stopes. Different types of analysis have been used to classify the observed cases into stable, potentially unstable and unstable groups. The main purpose of this paper is to present a new method for defining rock stability areas of the critical span graph, which applies machine learning classifiers (support vector machine and extreme learning machine). The results show a reasonable correlation with previous guidelines. These machine learning methods are good tools for developing empirical methods, since they make no assumptions about the regression function. With this software, it is easy to add new field observations to a previous database, improving prediction output with the addition of data that consider the local conditions for each mine.
Assembly, Integration, and Test Methods for Operationally Responsive Space Satellites
2010-03-01
like assembly and vibration tests, to ensure there have been no failures induced by the activities. External thermal control blankets and radiator...configuration of the satellite post- vibration test and adds time to the process. • Thermal blanketing is not realistic with current technology or...patterns for thermal blankets and radiator tape. The computer aided drawing (CAD) solid model was used to generate patterns that were cut and applied real
Making the Cut: Lattice Kirigami Rules
NASA Astrophysics Data System (ADS)
Castle, Toen; Cho, Yigil; Gong, Xingting; Jung, Euiyeon; Sussman, Daniel M.; Yang, Shu; Kamien, Randall D.
2014-12-01
In this Letter we explore and develop a simple set of rules that apply to cutting, pasting, and folding honeycomb lattices. We consider origami-like structures that are extrinsically flat away from zero-dimensional sources of Gaussian curvature and one-dimensional sources of mean curvature, and our cutting and pasting rules maintain the intrinsic bond lengths on both the lattice and its dual lattice. We find that a small set of rules is allowed providing a framework for exploring and building kirigami—folding, cutting, and pasting the edges of paper.
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.
Yun, Kyung-Jin; Han, Kyungdo; Kim, Mee Kyoung; Park, Yong-Moon; Baek, Ki-Hyun; Song, Ki-Ho; Kwon, Hyuk-Sang
2016-01-01
Background We sought to identify the distribution and cut-off value of the ‘homeostasis model assessment of insulin resistance’ (HOMA-IR) according to gender and menopausal status for metabolic syndrome in Koreans. Methods Data were from the Korean National Health and Nutrition Examination Survey in 2008–2010. The subjects included adults aged 20 years or older. We excluded participants who had diabetes or fasting serum glucose ≥ 7 mmol/L. Finally, 11,121 subjects (4,911 men, 3,597 premenopausal women, 2,613 postmenopausal women) were enrolled. The modified Adult Treatment Panel III criteria were used to define metabolic syndrome. Results The mean HOMA-IR was 2.11 (2.07–2.15) for men, 2.0 (1.97–2.04) for premenopausal women, and 2.14 (2.2–2.19) for postmenopausal women. The first cut-off values in men, premenopausal women, and postmenopausal women were 2.23 (sensitivity 70.6%, specificity 66.9%), 2.39 (sensitivity 72.3%, specificity 76.4%), and 2.48 (sensitivity 51.9%, specificity 80.2%), respectively. Based on the first HOMA-IR cut-off value, the prevalence of metabolic syndrome was 22.9% in men, 13.7% in premenopausal women, and 51.6% in postmenopausal women. The second cut-off value was around 3.2 in all three groups. Based on the second HOMA-IR cut-off value, the prevalence of metabolic syndrome was 50.8% in men, 42.5% in premenopausal women, and 71.6% in postmenopausal women. Conclusion In conclusion, the first cut-off values for HOMA-IR were 2.2–2.5 and the second cut-off value was 3.2 in Korea. The distribution of HOMA-IR showed differences according to gender and menopausal status. When we apply HOMA-IR, we should consider gender, menopausal status, and the prevalence of metabolic syndrome. PMID:27128847
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...
High Resolution DNS of Turbulent Flows using an Adaptive, Finite Volume Method
NASA Astrophysics Data System (ADS)
Trebotich, David
2014-11-01
We present a new computational capability for high resolution simulation of incompressible viscous flows. Our approach is based on cut cell methods where an irregular geometry such as a bluff body is intersected with a rectangular Cartesian grid resulting in cut cells near the boundary. In the cut cells we use a conservative discretization based on a discrete form of the divergence theorem to approximate fluxes for elliptic and hyperbolic terms in the Navier-Stokes equations. Away from the boundary the method reduces to a finite difference method. The algorithm is implemented in the Chombo software framework which supports adaptive mesh refinement and massively parallel computations. The code is scalable to 200,000 + processor cores on DOE supercomputers, resulting in DNS studies at unprecedented scale and resolution. For flow past a cylinder in transition (Re = 300) we observe a number of secondary structures in the far wake in 2D where the wake is over 120 cylinder diameters in length. These are compared with the more regularized wake structures in 3D at the same scale. For flow past a sphere (Re = 600) we resolve an arrowhead structure in the velocity in the near wake. The effectiveness of AMR is further highlighted in a simulation of turbulent flow (Re = 6000) in the contraction of an oil well blowout preventer. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research, Applied Mathematics program under Contract Number DE-AC02-05-CH11231.
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.
The ‘cut and push’ technique: is it really safe?
Peacock, Oliver; Singh, Rajeev; Cole, Andrew; Speake, William
2012-01-01
Percutaneous endoscopic gastrostomy (PEG) feeding is routinely used as an endoscopic and effective method for providing enteral nutrition in those whose oral access has been diminished or lost. One technique for removal of the PEG is cutting the tube at the skin level and allowing the tube and internal flange to pass spontaneously. This is known as the ‘cut and push’ method. Several studies have concluded that the ‘cut and push’ method is a safe and cost-effective method. This case demonstrates a rare cause of small bowel obstruction following the ‘cut and push’ method for PEG replacement, with only a few other cases been reported. This method of removal should be avoided in patients with previous abdominal surgery. It is important that the PEG flange is retrieved endoscopically or an alternative PEG tube (designed to be completely removed through the skin) is used to prevent this complication occurring in such individuals. PMID:22847571
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.
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.
NASA Astrophysics Data System (ADS)
Yudasari, N.; Prasetyo, S.; Suliyanti, M. M.
2018-03-01
The laser-induced breakdown spectroscopy (LIBS) technique was applied to detect the nutrient elements contained in fresh carrot. Nd:YAG laser the wavelength of 1064 nm was employed in the experiments for ablation. Employing simple set-up of LIBS and preparing the sample with less step method, we are able to detect 18 chemical elements including some fundamental element of carrot, i.e Mg, Al, Fe, Mn, Ti, Ca, and Mn. By applying normalized profiles calculation on some of the element, we are able to compare the concentration level of each element of the outer and inner part of carrot.
Development of economic and environmental metrics for forest-based biomass harvesting
NASA Astrophysics Data System (ADS)
Zhang, F. L.; Wang, J. J.; Liu, S. H.; Zhang, S. M.
2016-08-01
An assessment of the economic, energy consumption, and greenhouse gas (GHG) emission dimensions of forest-based biomass harvest stage in the state of Michigan, U.S. through gathering data from literature, database, and other relevant sources, was performed. The assessment differentiates harvesting systems (cut-to-length harvesting, whole tree harvesting, and motor-manual harvesting), harvest types (30%, 70%, and 100% cut) and forest types (hardwoods, softwoods, mixed hardwood/softwood, and softwood plantations) that characterize Michigan's logging industry. Machine rate methods were employed to determine unit harvesting cost. A life cycle inventory was applied to calculating energy demand and GHG emissions of different harvesting scenarios, considering energy and material inputs (diesel, machinery, etc.) and outputs (emissions) for each process (cutting, forwarding/skidding, etc.). A sensitivity analysis was performed for selected input variables for the harvesting operation in order to explore their relative importance. The results indicated that productivity had the largest impact on harvesting cost followed by machinery purchase price, yearly scheduled hours, and expected utilization. Productivity and fuel use, as well as fuel factors, are the most influential environmental impacts of harvesting operations.
Large area substrate for surface enhanced Raman spectroscopy (SERS) using glass-drawing technique
Ivanov, Ilia N; Simpson, John T
2012-06-26
A method of making a large area substrate comprises drawing a plurality of tubes to form a plurality of drawn tubes, and cutting the plurality of drawn tubes into cut drawn tubes. Each cut drawn tube has a first end and a second end along the longitudinal direction of the respective cut drawn tube. The cut drawn tubes collectively have a predetermined periodicity. The method of making a large area substrate also comprises forming a metal layer on the first ends of the cut drawn tubes to provide a large area substrate.
A new nanosecond UV laser at 355 nm: early results of corneal flap cutting in a rabbit model.
Trost, Andrea; Schrödl, Falk; Strohmaier, Clemens; Bogner, Barbara; Runge, Christian; Kaser-Eichberger, Alexandra; Krefft, Karolina; Vogel, Alfred; Linz, Norbert; Freidank, Sebastian; Hilpert, Andrea; Zimmermann, Inge; Grabner, Günther; Reitsamer, Herbert A
2013-12-03
A new 355 nm UV laser was used for corneal flap cutting in an animal model and tested for clinical and morphologic alterations. Corneal flaps were created (Chinchilla Bastards; n = 25) with an UV nanosecond laser at 355 nm (150 kHz, pulse duration 850 ps, spot-size 1 μm, spot spacing 6 × 6 μm, side cut Δz 1 μm; cutting depth 130 μm) and pulse energies of 2.2 or 2.5 μJ, respectively. Following slit-lamp examination, animals were killed at 6, 12, and 24 hours after treatment. Corneas were prepared for histology (hematoxylin and eosin [HE], TUNEL-assay) and evaluated statistically, followed by ultrastructural investigations. Laser treatment was tolerated well, flap lift was easier at 2.5 μJ compared with 2.2 μJ. Standard HE at 24 hours revealed intact epithelium in the horizontal cut, with similar increase in corneal thickness at both energies. Irrespective of energy levels, TUNEL assay revealed comparable numbers of apoptotic cells in the horizontal and vertical cut at 6, 12, and 24 hours, becoming detectable in the horizontal cut as an acellular stromal band at 24 hours. Ultrastructural analysis revealed regular morphology in the epi- and endothelium, while in the stroma, disorganized collagen lamellae were detectable representing the horizontal cut, again irrespective of energy levels applied. This new UV laser revealed no epi- nor endothelial damage at energies feasible for corneal flap cutting. Observed corneal swelling was lower compared with existing UV laser studies, albeit total energy applied here was much higher. Observed loss of stromal keratinocytes is comparable with available laser systems. Therefore, this new laser is suitable for refractive surgery, awaiting its test in a chronic environment.
Mutlu, Ibrahim; Ozkan, Arif; Kisioglu, Yasin
2016-01-01
Background. In this study, the cut-out risk of Dynamic Hip Screw (DHS) was investigated in nine different positions of the lag screw for two fracture types by using Finite Element Analysis (FEA). Methods. Two types of fractures (31-A1.1 and A2.1 in AO classification) were generated in the femur model obtained from Computerized Tomography images. The DHS model was placed into the fractured femur model in nine different positions. Tip-Apex Distances were measured using SolidWorks. In FEA, the force applied to the femoral head was determined according to the maximum value being observed during walking. Results. The highest volume percentage exceeding the yield strength of trabecular bone was obtained in posterior-inferior region in both fracture types. The best placement region for the lag screw was found in the middle of both fracture types. There are compatible results between Tip-Apex Distances and the cut-out risk except for posterior-superior and superior region of 31-A2.1 fracture type. Conclusion. The position of the lag screw affects the risk of cut-out significantly. Also, Tip-Apex Distance is a good predictor of the cut-out risk. All in all, we can supposedly say that the density distribution of the trabecular bone is a more efficient factor compared to the positions of lag screw in the cut-out risk. PMID:27995133
Li, Zhe-Xuan; Huang, Lei-Lei; Liu, Cong; Formichella, Luca; Zhang, Yang; Wang, Yu-Mei; Zhang, Lian; Ma, Jun-Ling; Liu, Wei-Dong; Ulm, Kurt; Wang, Jian-Xi; Zhang, Lei; Bajbouj, Monther; Li, Ming; Vieth, Michael; Quante, Michael; Zhou, Tong; Wang, Le-Hua; Suchanek, Stepan; Soutschek, Erwin; Schmid, Roland; Classen, Meinhard; You, Wei-Cheng; Gerhard, Markus; Pan, Kai-Feng
2017-05-18
The performance of diagnostic tests in intervention trials of Helicobacter pylori (H.pylori) eradication is crucial, since even minor inaccuracies can have major impact. To determine the cut-off point for 13 C-urea breath test ( 13 C-UBT) and to assess if it can be further optimized by serologic testing, mathematic modeling, histopathology and serologic validation were applied. A finite mixture model (FMM) was developed in 21,857 subjects, and an independent validation by modified Giemsa staining was conducted in 300 selected subjects. H.pylori status was determined using recomLine H.pylori assay in 2,113 subjects with a borderline 13 C-UBT results. The delta over baseline-value (DOB) of 3.8 was an optimal cut-off point by a FMM in modelling dataset, which was further validated as the most appropriate cut-off point by Giemsa staining (sensitivity = 94.53%, specificity = 92.93%). In the borderline population, 1,468 subjects were determined as H.pylori positive by recomLine (69.5%). A significant correlation between the number of positive H.pylori serum responses and DOB value was found (r s = 0.217, P < 0.001). A mathematical approach such as FMM might be an alternative measure in optimizing the cut-off point for 13 C-UBT in community-based studies, and a second method to determine H.pylori status for subjects with borderline value of 13 C-UBT was necessary and recommended.
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.
Gaussian Multiscale Aggregation Applied to Segmentation in Hand Biometrics
de Santos Sierra, Alberto; Ávila, Carmen Sánchez; Casanova, Javier Guerra; del Pozo, Gonzalo Bailador
2011-01-01
This paper presents an image segmentation algorithm based on Gaussian multiscale aggregation oriented to hand biometric applications. The method is able to isolate the hand from a wide variety of background textures such as carpets, fabric, glass, grass, soil or stones. The evaluation was carried out by using a publicly available synthetic database with 408,000 hand images in different backgrounds, comparing the performance in terms of accuracy and computational cost to two competitive segmentation methods existing in literature, namely Lossy Data Compression (LDC) and Normalized Cuts (NCuts). The results highlight that the proposed method outperforms current competitive segmentation methods with regard to computational cost, time performance, accuracy and memory usage. PMID:22247658
Gaussian multiscale aggregation applied to segmentation in hand biometrics.
de Santos Sierra, Alberto; Avila, Carmen Sánchez; Casanova, Javier Guerra; del Pozo, Gonzalo Bailador
2011-01-01
This paper presents an image segmentation algorithm based on Gaussian multiscale aggregation oriented to hand biometric applications. The method is able to isolate the hand from a wide variety of background textures such as carpets, fabric, glass, grass, soil or stones. The evaluation was carried out by using a publicly available synthetic database with 408,000 hand images in different backgrounds, comparing the performance in terms of accuracy and computational cost to two competitive segmentation methods existing in literature, namely Lossy Data Compression (LDC) and Normalized Cuts (NCuts). The results highlight that the proposed method outperforms current competitive segmentation methods with regard to computational cost, time performance, accuracy and memory usage.
Taguchi method for partial differential equations with application in tumor growth.
Ilea, M; Turnea, M; Rotariu, M; Arotăriţei, D; Popescu, Marilena
2014-01-01
The growth of tumors is a highly complex process. To describe this process, mathematical models are needed. A variety of partial differential mathematical models for tumor growth have been developed and studied. Most of those models are based on the reaction-diffusion equations and mass conservation law. A variety of modeling strategies have been developed, each focusing on tumor growth. Systems of time-dependent partial differential equations occur in many branches of applied mathematics. The vast majority of mathematical models in tumor growth are formulated in terms of partial differential equations. We propose a mathematical model for the interactions between these three cancer cell populations. The Taguchi methods are widely used by quality engineering scientists to compare the effects of multiple variables, together with their interactions, with a simple and manageable experimental design. In Taguchi's design of experiments, variation is more interesting to study than the average. First, Taguchi methods are utilized to search for the significant factors and the optimal level combination of parameters. Except the three parameters levels, other factors levels other factors levels would not be considered. Second, cutting parameters namely, cutting speed, depth of cut, and feed rate are designed using the Taguchi method. Finally, the adequacy of the developed mathematical model is proved by ANOVA. According to the results of ANOVA, since the percentage contribution of the combined error is as small. Many mathematical models can be quantitatively characterized by partial differential equations. The use of MATLAB and Taguchi method in this article illustrates the important role of informatics in research in mathematical modeling. The study of tumor growth cells is an exciting and important topic in cancer research and will profit considerably from theoretical input. Interpret these results to be a permanent collaboration between math's and medical oncologists.
Influence of microwave sterilization on the cutting capacity of carbide burs.
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
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
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.
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.
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…
Generalised Pareto distribution: impact of rounding on parameter estimation
NASA Astrophysics Data System (ADS)
Pasarić, Z.; Cindrić, K.
2018-05-01
Problems that occur when common methods (e.g. maximum likelihood and L-moments) for fitting a generalised Pareto (GP) distribution are applied to discrete (rounded) data sets are revealed by analysing the real, dry spell duration series. The analysis is subsequently performed on generalised Pareto time series obtained by systematic Monte Carlo (MC) simulations. The solution depends on the following: (1) the actual amount of rounding, as determined by the actual data range (measured by the scale parameter, σ) vs. the rounding increment (Δx), combined with; (2) applying a certain (sufficiently high) threshold and considering the series of excesses instead of the original series. For a moderate amount of rounding (e.g. σ/Δx ≥ 4), which is commonly met in practice (at least regarding the dry spell data), and where no threshold is applied, the classical methods work reasonably well. If cutting at the threshold is applied to rounded data—which is actually essential when dealing with a GP distribution—then classical methods applied in a standard way can lead to erroneous estimates, even if the rounding itself is moderate. In this case, it is necessary to adjust the theoretical location parameter for the series of excesses. The other solution is to add an appropriate uniform noise to the rounded data ("so-called" jittering). This, in a sense, reverses the process of rounding; and thereafter, it is straightforward to apply the common methods. Finally, if the rounding is too coarse (e.g. σ/Δx 1), then none of the above recipes would work; and thus, specific methods for rounded data should be applied.
[Histochemical stains for minerals by hematoxylin-lake method].
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.
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.
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.
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.
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.
Response of feline intradental nerve fibers to tooth cutting by Er:YAG laser.
Chaiyavej, S; Yamamoto, H; Takeda, A; Suda, H
2000-01-01
The aim of this study was to investigate the response of intradental A- and C-fibers during tooth cutting by Er:YAG laser. Bipolar electrical stimulation was applied to the cat's canine to identify functional single nerve fibers of the inferior alveolar nerve. The tip of the canine tooth was cut in 0.5-mm steps until the pulp was exposed. Teeth were alternately cut by using Er:YAG laser (50 mJ, 5 pps) and micromotor under water cooling. The nerve response recorded from the single nerve fibers during laser cutting was compared with that during micromotor cutting. All 26 A-fibers responded to laser cutting with high frequency of nerve firings. The nerve firing rate was significantly higher during laser cutting compared with that during micromotor cutting of superficial dentin (Chi(2) test, P < 0.05) but was not significantly different at deep dentin (P > or = 0. 05). Nine of 11 C-fibers responded to laser cutting when the deep dentin was cut. Among those nine nerve fibers, three also showed a low frequency response to laser cutting of the superficial dentin. During the tooth cutting, Er:YAG laser was more effective in activating intradental A-fibers compared with micromotor and also caused the activation of intradental C-fibers. Copyright 2000 Wiley-Liss, Inc.
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.
Cutting process simulation of flat drill
NASA Astrophysics Data System (ADS)
Tamura, Shoichi; Matsumura, Takashi
2018-05-01
Flat drills at a point angle of 180 deg. have recently been developed for drilling of automobile parts with the inclination of the workpiece surfaces. The paper studies the cutting processes of the flat drills in the analytical simulation. A predictive force model is applied to simulation of the cutting force with the chip flow direction. The chip flow model is piled up with orthogonal cuttings in the plane containing the cutting velocities and the chip flow velocities, in which the chip flow direction is determined to minimize the cutting energy. Then, the cutting force is predicted in the determined in the chip flow model. The typical cutting force of the flat drill is discussed with comparing to that of the standard drill. The typical differences are confirmed in the cutting force change during the tool engagement and disengagement. The cutting force, then, is simulated in drilling for an inclined workpiece with a flat drill. The horizontal components in the cutting forces are simulated with changing the inclination angle of the plate. The horizontal force component in the flat drilling is stable to be controlled in terms of the machining accuracy and the tool breakage.
Apparatus and method for cutting soft materials, especially meat
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.
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.
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.
Wang, Yu; Cao, Meng; Zhao, Xiangrui; Zhu, Gang; McClean, Colin; Zhao, Yuanyuan; Fan, Yubo
2014-11-01
Heat generated during bone drilling could cause irreversible thermal damage, which can lead to bone necrosis or even osteomyelitis. In this study, vibrational drilling was applied to fresh bovine bones to investigate the cutting heat in comparison with conventional drilling through experimental investigation and finite element analysis (FEA). The influence of vibrational frequency and amplitude on cutting heat generation and conduction were studied. The experimental results showed that, compared with the conventional drilling, vibrational drilling could significantly reduce the cutting temperature in drilling of cortical bone (P<0.05): the cutting temperature tended to decrease with increasing vibrational frequency and amplitude. The FEA results also showed that the vibrational amplitude holds a significant effect on the cutting heat conduction. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bondarenko, J. A.; Fedorenko, M. A.; Pogonin, A. A.
2018-03-01
Large parts can be treated without disassembling machines using “Extra”, having technological and design challenges, which differ from the challenges in the processing of these components on the stationary machine. Extension machines are used to restore large parts up to the condition allowing one to use them in a production environment. To achieve the desired accuracy and surface roughness parameters, the surface after rotary grinding becomes recoverable, which greatly increases complexity. In order to improve production efficiency and productivity of the process, the qualitative rotary processing of the machined surface is applied. The rotary cutting process includes a continuous change of the cutting edge surfaces. The kinematic parameters of a rotary cutting define its main features and patterns, the cutting operation of the rotary cutting instrument.
NASA Astrophysics Data System (ADS)
Venkata Subbaiah, K.; Raju, Ch.; Suresh, Ch.
2017-08-01
The present study aims to compare the conventional cutting inserts with wiper cutting inserts during the hard turning of AISI 4340 steel at different workpiece hardness. Type of insert, hardness, cutting speed, feed, and depth of cut are taken as process parameters. Taguchi’s L18 orthogonal array was used to conduct the experimental tests. Parametric analysis carried in order to know the influence of each process parameter on the three important Surface Roughness Characteristics (Ra, Rz, and Rt) and Material Removal Rate. Taguchi based Grey Relational Analysis (GRA) used to optimize the process parameters for individual response and multi-response outputs. Additionally, the analysis of variance (ANOVA) is also applied to identify the most significant factor.
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.
[Comparisons of different methods for virus-elimination of edible fungi].
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.
[A graph cuts-based interactive method for segmentation of magnetic resonance images of meningioma].
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...
Zooming in: high resolution 3D reconstruction of differently stained histological whole slide images
NASA Astrophysics Data System (ADS)
Lotz, Johannes; Berger, Judith; Müller, Benedikt; Breuhahn, Kai; Grabe, Niels; Heldmann, Stefan; Homeyer, André; Lahrmann, Bernd; Laue, Hendrik; Olesch, Janine; Schwier, Michael; Sedlaczek, Oliver; Warth, Arne
2014-03-01
Much insight into metabolic interactions, tissue growth, and tissue organization can be gained by analyzing differently stained histological serial sections. One opportunity unavailable to classic histology is three-dimensional (3D) examination and computer aided analysis of tissue samples. In this case, registration is needed to reestablish spatial correspondence between adjacent slides that is lost during the sectioning process. Furthermore, the sectioning introduces various distortions like cuts, folding, tearing, and local deformations to the tissue, which need to be corrected in order to exploit the additional information arising from the analysis of neighboring slide images. In this paper we present a novel image registration based method for reconstructing a 3D tissue block implementing a zooming strategy around a user-defined point of interest. We efficiently align consecutive slides at increasingly fine resolution up to cell level. We use a two-step approach, where after a macroscopic, coarse alignment of the slides as preprocessing, a nonlinear, elastic registration is performed to correct local, non-uniform deformations. Being driven by the optimization of the normalized gradient field (NGF) distance measure, our method is suitable for differently stained and thus multi-modal slides. We applied our method to ultra thin serial sections (2 μm) of a human lung tumor. In total 170 slides, stained alternately with four different stains, have been registered. Thorough visual inspection of virtual cuts through the reconstructed block perpendicular to the cutting plane shows accurate alignment of vessels and other tissue structures. This observation is confirmed by a quantitative analysis. Using nonlinear image registration, our method is able to correct locally varying deformations in tissue structures and exceeds the limitations of globally linear transformations.
ERIC Educational Resources Information Center
Cutting Edge, 2000
2000-01-01
The Cutting Edge is a bimonthly newsletter of the Regional Center for Applied Technology and Training at Danville Community College (DCC) (Virginia) that provides the latest information on a wide range of issues including technology, business, employment trends, and new legislation. Articles from the first five issues discuss: (1) the July 2000…
Improved estimation of nitrogen uptake in grasslands using the nitrogen dilution curve
USDA-ARS?s Scientific Manuscript database
The critical nitrogen concentration (CNC) is a simple yet robust relationship that describes the changes in crop N during growth. We applied the concept of CNC to calculate N uptake across various cutting regimes. While it is well-established that decreasing cutting frequency changes growth rates, t...
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.
Hydrogen peroxide test for intraoperative bile leak detection.
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.
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.
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.
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.
Integrand reduction for two-loop scattering amplitudes through multivariate polynomial division
NASA Astrophysics Data System (ADS)
Mastrolia, Pierpaolo; Mirabella, Edoardo; Ossola, Giovanni; Peraro, Tiziano
2013-04-01
We describe the application of a novel approach for the reduction of scattering amplitudes, based on multivariate polynomial division, which we have recently presented. This technique yields the complete integrand decomposition for arbitrary amplitudes, regardless of the number of loops. It allows for the determination of the residue at any multiparticle cut, whose knowledge is a mandatory prerequisite for applying the integrand-reduction procedure. By using the division modulo Gröbner basis, we can derive a simple integrand recurrence relation that generates the multiparticle pole decomposition for integrands of arbitrary multiloop amplitudes. We apply the new reduction algorithm to the two-loop planar and nonplanar diagrams contributing to the five-point scattering amplitudes in N=4 super Yang-Mills and N=8 supergravity in four dimensions, whose numerator functions contain up to rank-two terms in the integration momenta. We determine all polynomial residues parametrizing the cuts of the corresponding topologies and subtopologies. We obtain the integral basis for the decomposition of each diagram from the polynomial form of the residues. Our approach is well suited for a seminumerical implementation, and its general mathematical properties provide an effective algorithm for the generalization of the integrand-reduction method to all orders in perturbation theory.
Monitoring of Surface Roughness in Aluminium Turning Process
NASA Astrophysics Data System (ADS)
Chaijareenont, Atitaya; Tangjitsitcharoen, Somkiat
2018-01-01
As the turning process is one of the most necessary process. The surface roughness has been considered for the quality of workpiece. There are many factors which affect the surface roughness. Hence, the objective of this research is to monitor the relation between the surface roughness and the cutting forces in aluminium turning process with a wide range of cutting conditions. The coated carbide tool and aluminium alloy (Al 6063) are used for this experiment. The cutting parameters are investigated to analyze the effects of them on the surface roughness which are the cutting speed, the feed rate, the tool nose radius and the depth of cut. In the case of this research, the dynamometer is installed in the turret of CNC turning machine to generate a signal while turning. The relation between dynamic cutting forces and the surface roughness profile is examined by applying the Fast Fourier Transform (FFT). The experimentally obtained results showed that the cutting force depends on the cutting condition. The surface roughness can be improved when increasing the cutting speed and the tool nose radius in contrast to the feed rate and the depth of cut. The relation between the cutting parameters and the surface roughness can be explained by the in-process cutting forces. It is understood that the in-process cutting forces are able to predict the surface roughness in the further research.
Financial Distress Prediction Using Discrete-time Hazard Model and Rating Transition Matrix Approach
NASA Astrophysics Data System (ADS)
Tsai, Bi-Huei; Chang, Chih-Huei
2009-08-01
Previous studies used constant cut-off indicator to distinguish distressed firms from non-distressed ones in the one-stage prediction models. However, distressed cut-off indicator must shift according to economic prosperity, rather than remains fixed all the time. This study focuses on Taiwanese listed firms and develops financial distress prediction models based upon the two-stage method. First, this study employs the firm-specific financial ratio and market factors to measure the probability of financial distress based on the discrete-time hazard models. Second, this paper further focuses on macroeconomic factors and applies rating transition matrix approach to determine the distressed cut-off indicator. The prediction models are developed by using the training sample from 1987 to 2004, and their levels of accuracy are compared with the test sample from 2005 to 2007. As for the one-stage prediction model, the model in incorporation with macroeconomic factors does not perform better than that without macroeconomic factors. This suggests that the accuracy is not improved for one-stage models which pool the firm-specific and macroeconomic factors together. In regards to the two stage models, the negative credit cycle index implies the worse economic status during the test period, so the distressed cut-off point is adjusted to increase based on such negative credit cycle index. After the two-stage models employ such adjusted cut-off point to discriminate the distressed firms from non-distressed ones, their error of misclassification becomes lower than that of one-stage ones. The two-stage models presented in this paper have incremental usefulness in predicting financial distress.
3rd congress on applied synthetic biology in Europe (Costa da Caparica, Portugal, February 2016).
Cueva, Miguel
2017-03-25
The third meeting organised by the European Federation of Biotechnology (EFB) on advances in Applied Synthetic Biotechnology in Europe (ASBE) was held in Costa da Caparica, Portugal, in February 2016. Abundant novel applications in synthetic biology were described in the six sessions of the meeting, which was divided into technology and tools for synthetic biology (I, II and III), bionanoscience, biosynthetic pathways and enzyme synthetic biology, and metabolic engineering and chemical manufacturing. The meeting presented numerous methods for the development of novel synthetic strains, synthetic biological tools and synthetic biology applications. With the aid of synthetic biology, production costs of chemicals, metabolites and food products are expected to decrease, by generating sustainable biochemical production of such resources. Also, such synthetic biological advances could be applied for medical purposes, as in pharmaceuticals and for biosensors. Recurrent, linked themes throughout the meeting were the shortage of resources, the world's transition into a bioeconomy, and how synthetic biology is helping tackle these issues through cutting-edge technologies. While there are still limitations in synthetic biology research, innovation is propelling the development of technology, the standardisation of synthetic biological tools and the use of suitable host organisms. These developments are laying a foundation to providing a future where cutting-edge research could generate potential solutions to society's pressing issues, thus incentivising a transition into a bioeconomy. Copyright © 2016 Elsevier B.V. All rights reserved.
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.
Borelli, Joao; Bello, Fernando; Rodriguez Y Bena, Ferdinando; Davies, Brian
2004-01-01
Master/slave telemanipulator systems can be applied in minimally invasive heart surgery. However, due to the beating heart and difficulties of finding inner points inside the heart, a surgical task operation such as cutting can be very difficult. In order to avoid surgical error, the "active constraint" concept can be applied. This paper shows an example of an "active constraint" environment used for minimally invasive heart surgery. Experiments have been carried out for a 2-DOF master and the preliminary results validate the present approach.
Means and method for nonuniform poling of piezoelectric transducers
Hsu, D.K.; Margetan, F.J.; Hasselbusch, M.D.; Wormley, S.J.; Hughes, M.S.; Thompson, D.O.
1990-10-09
An apparatus and method are disclosed for nonuniform poling of piezoelectric transducers includes machining one or more indentation into an end of a piezoelectric rod and cutting the rod to present a thickened disk shape. Highly electrically conductive material is deposited on at least the indentations in the one end and on at least portions of the opposite face of the member. One or more electrodes are configured to matingly fit within the indentations on the one face of the disk, with a like number of electrodes being positionable on the opposite face of the material. Electrical power is then applied to the electrodes in desired amounts, polarity, and duration. The indentations vary the electrical field produced within the piezoelectric material to produce nonuniform poling in the material. The thick disk is then cut to remove the indentations and to present a thin, flat two sided disk for installation in a conventional piezoelectric transducer probe. The indentations are selected to produce poling in accordance with desired transducer response profiles such as Gaussian or Bessel functions. 14 figs.
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.
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
Diffractive elements for generating microscale laser beam patterns: a Y2K problem
NASA Astrophysics Data System (ADS)
Teiwes, Stephan; Krueger, Sven; Wernicke, Guenther K.; Ferstl, Margit
2000-03-01
Lasers are widely used in industrial fabrication for engraving, cutting and many other purposes. However, material processing at very small scales is still a matter of concern. Advances in diffractive optics could provide for laser systems that could be used for engraving or cutting of micro-scale patterns at high speeds. In our paper we focus on the design of diffractive elements which can be used for this special application. It is a common desire in material processing to apply 'discrete' as well as 'continuous' beam patterns. Especially, the latter case is difficult to handle as typical micro-scale patterns are characterized by bad band-limitation properties, and as speckles can easily occur in beam patterns. It is shown in this paper that a standard iterative design method usually fails to obtain diffractive elements that generate diffraction patterns with acceptable quality. Insights gained from an analysis of the design problems are used to optimize the iterative design method. We demonstrate applicability and success of our approach by the design of diffractive phase elements that generate a discrete and a continuous 'Y2K' pattern.
Retrograde endopyelotomy: a comparison between laser and Acucise balloon cutting catheter.
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.
Visual detection of gas shows from coal core and cuttings using liquid leak detector
Barker, C.E.
2006-01-01
Portions of core or cutting samples that have active gas shows can be identified by applying a liquid leak detector to the core surface. Although these gas shows can be caused by manmade changes to the coals' internal structure and surface of the core during the coring process, in many cases, the marked gas shows overlie changes in maceral composition, subtle fractures or coal, coal structure and so forth that seemingly are places where natural primary permeability is higher and gas shows would be favored. Given the limited time available for core description before a core is closed in a canister, using the liquid leak detector method to mark gas shows enhances core description by providing a photographic record of places of apparently increased gas flow likely related to enhanced coal permeability that cannot be easily detected otherwise.
Mitigating cutting-induced plasticity in the contour method, Part 2: Numerical analysis
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
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.
Vegetative propagation of Cecropia obtusifolia (Cecropiaceae).
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
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.
Burnout in the staff of a chronic care hospital.
Merino-Plaza, Maria Jose; Carrera-Hueso, Francisco Javier; Arribas-Boscá, Nuria; Martínez-Asensi, Amparo; Trull-Maravilla, Emilia; Fikri-Benbrahim, Narjis
2018-01-01
OBJECTIVE To estimate the prevalence of Burnout in a medium or long-stay hospital, to monitor its evolution and to highlight the importance of cut-off points used to avoid distortions in the interpretation of the results. METHODS Two cross-sectional studies (2013-2016) were carried out, applying the Spanish version of the Maslach Burnout Inventory to the staff of a chronic care hospital (n = 323). Result variables were: Burnout prevalence and a high degree of affectation of the subscales and predictor variables: sociodemographic characteristics and factors that trigger and modulate the syndrome. The association between variables was quantified using odds ratio. RESULTS The participation rate went from 31.5% to 39.3%. The professionals presented a mean level of Burnout in both moments, observing a lower degree of affectation of the depersonalization subscales and personal accomplishment in the 2016 cut-off. The average score of the subscales in 2016 was 21.5 for emotional fatigue, 4.7 for depersonalization and 41.7 for personal fulfillment, compared to the values of emotional fatigue = 21.6, depersonalization = 6.9 and personal fulfillment = 36.3 obtained in 2013. The emotional fatigue score was slightly higher than the mean value of the national studies (19.9), while the rest of the values were similar to the mean values of the studies considered. The prevalence of Burnout and the interpretation of the results varied significantly according to the cut-off points considered. In both studies, sociodemographic variables showed little significance, while social support and interpersonal relationships were associated with the degree of burnout among professionals. CONCLUSIONS Our prevalence of Burnout was similar to that of other studies consulted, although the emotional component is more marked in our environment. The interpretation of the results varied significantly according to the cut-off points applied, due to the cross-cultural differences.
Burnout in the staff of a chronic care hospital
Merino-Plaza, Maria Jose; Carrera-Hueso, Francisco Javier; Arribas-Boscá, Nuria; Martínez-Asensi, Amparo; Trull-Maravilla, Emilia; Fikri-Benbrahim, Narjis
2018-01-01
ABSTRACT OBJECTIVE To estimate the prevalence of Burnout in a medium or long-stay hospital, to monitor its evolution and to highlight the importance of cut-off points used to avoid distortions in the interpretation of the results. METHODS Two cross-sectional studies (2013–2016) were carried out, applying the Spanish version of the Maslach Burnout Inventory to the staff of a chronic care hospital (n = 323). Result variables were: Burnout prevalence and a high degree of affectation of the subscales and predictor variables: sociodemographic characteristics and factors that trigger and modulate the syndrome. The association between variables was quantified using odds ratio. RESULTS The participation rate went from 31.5% to 39.3%. The professionals presented a mean level of Burnout in both moments, observing a lower degree of affectation of the depersonalization subscales and personal accomplishment in the 2016 cut-off. The average score of the subscales in 2016 was 21.5 for emotional fatigue, 4.7 for depersonalization and 41.7 for personal fulfillment, compared to the values of emotional fatigue = 21.6, depersonalization = 6.9 and personal fulfillment = 36.3 obtained in 2013. The emotional fatigue score was slightly higher than the mean value of the national studies (19.9), while the rest of the values were similar to the mean values of the studies considered. The prevalence of Burnout and the interpretation of the results varied significantly according to the cut-off points considered. In both studies, sociodemographic variables showed little significance, while social support and interpersonal relationships were associated with the degree of burnout among professionals. CONCLUSIONS Our prevalence of Burnout was similar to that of other studies consulted, although the emotional component is more marked in our environment. The interpretation of the results varied significantly according to the cut-off points applied, due to the cross-cultural differences. PMID:29723388
The Effects of Cryogenic Treatment on Cutting Tools
NASA Astrophysics Data System (ADS)
Kumar, Satish; Khedkar, Nitin K.; Jagtap, Bhushan; Singh, T. P.
2017-08-01
Enhancing the cutting tool life is important and economic factor to reduce the tooling as well as manufacturing cost. The tool life is improved considerably by 92 % after cryogenic treatment. The cryogenic treatment is a one-time permanent, sub-zero heat treatment that entirely changes cross-section of cutting tool. The cryogenic treatment is carried out with deep freezing of cutting tool materials to enhance physical and mechanical properties. The cryogenic treatment improves mechanical such as hardness, toughness and tribological properties such as wear resistance, coefficient of friction, surface finish, dimensional stability and stress relief. The deep cryogenic treatment is the most beneficial treatment applied on cutting tools. The cryogenic treatment is the most advanced heat treatment and popular to improve performance of the cutting tool. The optimization of cryogenic treatment variables is necessary to improve tool life. This study reviews the effects of cryogenic treatment on microstructure, tribological properties of tool steels and machining applications of cutting tool by investigating the surface and performing the surface characterization test like SEM. The economy of cutting tool can be achieved by deep cryogenic treatment.
Engineering the shape and structure of materials by fractal cut.
Cho, Yigil; Shin, Joong-Ho; Costa, Avelino; Kim, Tae Ann; Kunin, Valentin; Li, Ju; Lee, Su Yeon; Yang, Shu; Han, Heung Nam; Choi, In-Suk; Srolovitz, David J
2014-12-09
In this paper we discuss the transformation of a sheet of material into a wide range of desired shapes and patterns by introducing a set of simple cuts in a multilevel hierarchy with different motifs. Each choice of hierarchical cut motif and cut level allows the material to expand into a unique structure with a unique set of properties. We can reverse-engineer the desired expanded geometries to find the requisite cut pattern to produce it without changing the physical properties of the initial material. The concept was experimentally realized and applied to create an electrode that expands to >800% the original area with only very minor stretching of the underlying material. The generality of our approach greatly expands the design space for materials so that they can be tuned for diverse applications.
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.
Xu, Jing; Wang, Zhongbin; Tan, Chao; Liu, Xinhua
2018-01-01
As a sound signal has the advantages of non-contacted measurement, compact structure, and low power consumption, it has resulted in much attention in many fields. In this paper, the sound signal of the coal mining shearer is analyzed to realize the accurate online cutting pattern identification and guarantee the safety quality of the working face. The original acoustic signal is first collected through an industrial microphone and decomposed by adaptive ensemble empirical mode decomposition (EEMD). A 13-dimensional set composed by the normalized energy of each level is extracted as the feature vector in the next step. Then, a swarm intelligence optimization algorithm inspired by bat foraging behavior is applied to determine key parameters of the traditional variable translation wavelet neural network (VTWNN). Moreover, a disturbance coefficient is introduced into the basic bat algorithm (BA) to overcome the disadvantage of easily falling into local extremum and limited exploration ability. The VTWNN optimized by the modified BA (VTWNN-MBA) is used as the cutting pattern recognizer. Finally, a simulation example, with an accuracy of 95.25%, and a series of comparisons are conducted to prove the effectiveness and superiority of the proposed method. PMID:29382120
Pérez-Fernández, Virginia; Castro-Puyana, María; González, María José; Marina, María Luisa; García, María Ángeles; Gómara, Belén
2012-07-01
The potential of three capillary columns based on β-cyclodextrin (i.e., Chirasil-Dex, BGB-172, and BGB-176SE) has been studied for the simultaneous enantiomeric separation of polychlorinated biphenyls (PCBs) and methylsulfonyl metabolites of PCBs (MeSO(2)-PCBs) employing a heart-cut multidimensional gas chromatographic system (heart-cut MDGC). Among the columns studied, the BGB-176SE capillary column provided the best results, allowing the simultaneous enantioselective resolution of six MeSO(2)-PCBs and six chiral PCBs; the Chirasil-Dex column did not resolve any of the studied MeSO(2)-PCBs; and a poor resolution was obtained for three MeSO(2)-PCBs when the BGB-172 column was employed. The developed method was successfully applied to two fish oil and one cow liver samples commercially available, which showed different enantioselective pattern. PCBs 91 and 176 presented a clear enrichment of the second eluted atropisomer in codfish oil, whereas in fish oil sample, slight enrichment of the first eluted atropisomer of CB45 and the second eluted atropisomer of CB136 were observed. © 2012 Wiley Periodicals, Inc.
Harmonic curved shears system prevent of bile leakage after liver resection in a pig model.
Shimoda, Mitsugi; Iwasaki, Yoshimi; Kubota, Keiichi
2014-01-01
We evaluated the efficacy of TachoComb (TC) collagen fleece and Harmonic Focus (HF) shears in a pig liver resection model. Pigs were divided into 3 groups of 7, in which vessels were tied with silk and TC was applied to the cut surfaces (Silk+TC group), sealed and sheared with HF and TC (HF+TC group), or sealed using HF alone (HF-TC group). After 1 month, we conducted a histologic evaluation and recorded the incidence of bile leakage with infected collections at the liver cut surface. Six pigs were evaluated in each group. In the Silk+TC group, 4 of the 6 pigs had infected collections at the cut surface. Histologically, the silk had remained under the fibrotic tissue, which contained remnants of TC fragments. In the HF+TC group, 5 of the 6 pigs also had infected collections, and histologically, TC had remained in the hard fibrotic tissues. In the HF-TC group, none of the 6 pigs had infected collections, and the histologic findings were normal. Use of the HF alone may be an effective method for preventing bile leakage in infected collections after liver resection.
2011-01-01
Background Dorsal root reflexes (DRRs) are antidromic activities traveling along the primary afferent fibers, which can be generated by peripheral stimulation or central stimulation. DRRs are thought to be involved in the generation of neurogenic inflammation, as indicated by plasma extravasation and vasodilatation. The hypothesis of this study was that electrical stimulation of the central stump of a cut dorsal root would lead to generation of DRRs, resulting in plasma extravasation and vasodilatation. Methods Sprague-Dawley rats were prepared to expose spinal cord and L4-L6 dorsal roots under pentobarbital general anesthesia. Electrical stimulation of either intact, proximal or distal, cut dorsal roots was applied while plasma extravasation or blood perfusion of the hindpaw was recorded. Results While stimulation of the peripheral stump of a dorsal root elicited plasma extravasation, electrical stimulation of the central stump of a cut dorsal root generated significant DRRs, but failed to induce plasma extravasation. However, stimulation of the central stump induced a significant increase in blood perfusion. Conclusions It is suggested that DRRs are involved in vasodilatation but not plasma extravasation in neurogenic inflammation in normal animals. PMID:21356101
NASA Astrophysics Data System (ADS)
Farina, Simone; Thepsonti, Thanongsak; Ceretti, Elisabetta; Özel, Tugrul
2011-05-01
Titanium alloys offer superb properties in strength, corrosion resistance and biocompatibility and are commonly utilized in medical devices and implants. Micro-end milling process is a direct and rapid fabrication method for manufacturing medical devices and implants in titanium alloys. Process performance and quality depend upon an understanding of the relationship between cutting parameters and forces and resultant tool deflections to avoid tool breakage. For this purpose, FE simulations of chip formation during micro-end milling of Ti-6Al-4V alloy with an ultra-fine grain solid carbide two-flute micro-end mill are investigated using DEFORM software. At first, specific forces in tangential and radial directions of cutting during micro-end milling for varying feed advance and rotational speeds have been determined using designed FE simulations for chip formation process. Later, these forces are applied to the micro-end mill geometry along the axial depth of cut in 3D analysis of ABAQUS. Consequently, 3D distributions for tool deflections & von Misses stress are determined. These analyses will yield in establishing integrated multi-physics process models for high performance micro-end milling and a leap-forward to process improvements.
Electronic packaging: new results in singulation by Laser Microjet
NASA Astrophysics Data System (ADS)
Wagner, Frank; Sibailly, Ochelio; Richerzhagen, Bernold
2004-07-01
Cutting electronic packages that are produced in a matrix array fashion is an important process and deals with the ready-to-use devices. Thus an increase in the singulation yield is directly correlated to an increase in benefit. Due to the usage of different substrate materials, the saws encounter big problems in terms of lifetime and constancy of cut quality in these applications. Today"s equipment manufacturers are not yet in the position to propose an adequate solution for all types of packages. Compared to classical laser cutting, the water-jet guided laser technology minimizes the heat damages in any kind of sample. This new material processing method consists in guiding a laser beam inside a hair thin, lowpressure water-jet by total internal reflection, and is applied to package singulation since two years approximately. Using a frequency doubled Nd:YAG laser guided by a water jet, an LTCC-ceramics based package is singulated according to a scribe and break process. Speeds of 2-10 mm/s are reached in the LTTC and 40 mm/s in the mold compound. The process is wear-free and provides very good edge quality of the LTCC and the mold compound as well as reliable separation of the packages.
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.
Rethinking Cuts in Public Education: An American Example.
ERIC Educational Resources Information Center
Fenton, Richard J.; Gardner, John; Singh, Sandeep
2001-01-01
Recent public higher education spending cuts have often been matched by tuition increases, resulting in possible declines in college graduates and in personal income tax receipts. Applying a net present-value model to quantify New York State data suggests that potential revenue losses quickly dwarf short-term budgetary savings. (Contains 21…
Prediction Of Abrasive And Diffusive Tool Wear Mechanisms In Machining
NASA Astrophysics Data System (ADS)
Rizzuti, S.; Umbrello, D.
2011-01-01
Tool wear prediction is regarded as very important task in order to maximize tool performance, minimize cutting costs and improve the quality of workpiece in cutting. In this research work, an experimental campaign was carried out at the varying of cutting conditions with the aim to measure both crater and flank tool wear, during machining of an AISI 1045 with an uncoated carbide tool P40. Parallel a FEM-based analysis was developed in order to study the tool wear mechanisms, taking also into account the influence of the cutting conditions and the temperature reached on the tool surfaces. The results show that, when the temperature of the tool rake surface is lower than the activation temperature of the diffusive phenomenon, the wear rate can be estimated applying an abrasive model. In contrast, in the tool area where the temperature is higher than the diffusive activation temperature, the wear rate can be evaluated applying a diffusive model. Finally, for a temperature ranges within the above cited values an adopted abrasive-diffusive wear model furnished the possibility to correctly evaluate the tool wear phenomena.
Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes
NASA Astrophysics Data System (ADS)
Umbrello, Domenico; Rizzuti, Stefania; Outeiro, José C.; Shivpuri, Rajiv
2007-04-01
In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change.
A rapid technique for the histological examination of large ovarian follicles.
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.
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.
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…
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.
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…
Fumey, Damien; Lauri, Pierre-Éric; Guédon, Yann; Godin, Christophe; Costes, Evelyne
2011-11-01
Manipulation of tree architecture by pruning provides an experimental context to analyze architectural plasticity resulting from competition between developing organs. The objective of this study was to quantify the effects of the removal of all or part of shoots through pruning on the redistribution of growth and flowering at spatial and temporal levels. Two types of pruning cuts were applied: (1) heading cuts of either the main stem or laterals and (2) thinning cuts (i.e., complete removal) of laterals. These two types of cuts were applied in summer and winter on 1-yr-old cultivars of Fuji and Braeburn apple trees. Tree topology and geometry were described over 3 years, and responses were analyzed for both local and distant scales. Heading cuts induced quasi-deterministic local responses on pruned axes, whereas responses to thinning cuts were more variable. For the main stem and laterals, responses over greater spatial and temporal scales were highlighted with (1) stronger growth the year after summer pruning and (2) modification of branching and flowering along the unpruned parts after winter pruning. Pruning typically induced growth redistribution toward traumatic reiterations and enhanced growth of the remaining unpruned axes with a concomitant decrease of flowering and cambial growth. Although results could be interpreted in relation to the root-shoot balance, tree responses appeared highly cultivar-specific.
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.
Belk, Rachel A; Pilling, Mark; Rogers, Katherine D; Lovell, Karina; Young, Alys
2016-11-03
The PHQ-9 and the GAD-7 assess depression and anxiety respectively. There are standardised, reliability-tested versions in BSL (British Sign Language) that are used with Deaf users of the IAPT service. The aim of this study is to determine their appropriate clinical cut-offs when used with Deaf people who sign and to examine the operating characteristics for PHQ-9 BSL and GAD-7 BSL with a clinical Deaf population. Two datasets were compared: (i) dataset (n = 502) from a specialist IAPT service for Deaf people; and (ii) dataset (n = 85) from our existing study of Deaf people who self-reported having no mental health difficulties. Parameter estimates, with the precision of AUC value, sensitivity, specificity, positive predicted value (ppv) and negative predicted value (npv), were carried out to provide the details of the clinical cut-offs. Three statistical choices were included: Maximising (Youden: maximising sensitivity + specificity), Equalising (Sensitivity = Specificity) and Prioritising treatment (False Negative twice as bad as False Positive). Standard measures (as defined by IAPT) were applied to examine caseness, recovery, reliable change and reliable recovery for the first dataset. The clinical cut-offs for PHQ-9 BSL and GAD-7 BSL are 8 and 6 respectively. This compares with the original English version cut-offs in the hearing population of 10 and 8 respectively. The three different statistical choices for calculating clinical cut-offs all showed a lower clinical cut-off for the Deaf population with respect to the PHQ-9 BSL and GAD-7 BSL with the exception of the Maximising criteria when used with the PHQ-9 BSL. Applying the new clinical cut-offs, the percentage of Deaf BSL IAPT service users showing reliable recovery is 54.0 % compared to 63.7 % using the cut-off scores used for English speaking hearing people. These compare favourably with national IAPT data for the general population. The correct clinical cut-offs for the PHQ-9 BSL and GAD-7 BSL enable meaningful measures of clinical effectiveness and facilitate appropriate access to treatment when required.
Faster processing of multiple spatially-heterodyned direct to digital holograms
Hanson, Gregory R.; Bingham, Philip R.
2006-10-03
Systems and methods are described for faster processing of multiple spatially-heterodyned direct to digital holograms. A method includes of obtaining multiple spatially-heterodyned holograms, includes: digitally recording a first spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; digitally recording a second spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; Fourier analyzing the recorded first spatially-heterodyned hologram by shifting a first original origin of the recorded first spatially-heterodyned hologram including spatial heterodyne fringes in Fourier space to sit on top of a spatial-heterodyne carrier frequency defined as a first angle between a first reference beam and a first, object beam; applying a first digital filter to cut off signals around the first original origin and performing an inverse Fourier transform on the result; Fourier analyzing the recorded second spatially-heterodyned hologram by shifting a second original origin of the recorded second spatially-heterodyned hologram including spatial heterodyne fringes in Fourier space to sit on top of a spatial-heterodyne carrier frequency defined as a second angle between a second reference beam and a second object beam; and applying a second digital filter to cut off signals around the second original origin and performing an inverse Fourier transform on the result, wherein digitally recording the first spatially-heterodyned hologram is completed before digitally recording the second spatially-heterodyned hologram and a single digital image includes both the first spatially-heterodyned hologram and the second spatially-heterodyned hologram.
Faster processing of multiple spatially-heterodyned direct to digital holograms
Hanson, Gregory R [Clinton, TN; Bingham, Philip R [Knoxville, TN
2008-09-09
Systems and methods are described for faster processing of multiple spatially-heterodyned direct to digital holograms. A method includes of obtaining multiple spatially-heterodyned holograms, includes: digitally recording a first spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; digitally recording a second spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; Fourier analyzing the recorded first spatially-heterodyned hologram by shifting a first original origin of the recorded first spatially-heterodyned hologram including spatial heterodyne fringes in Fourier space to sit on top of a spatial-heterodyne carrier frequency defined as a first angle between a first reference beam and a first object beam; applying a first digital filter to cut off signals around the first original origin and performing an inverse Fourier transform on the result; Fourier analyzing the recorded second spatially-heterodyned hologram by shifting a second original origin of the recorded second spatially-heterodyned hologram including spatial heterodyne fringes in Fourier space to sit on top of a spatial-heterodyne carrier frequency defined as a second angle between a second reference beam and a second object beam; and applying a second digital filter to cut off signals around the second original origin and performing an inverse Fourier transform on the result, wherein digitally recording the first spatially-heterodyned hologram is completed before digitally recording the second spatially-heterodyned hologram and a single digital image includes both the first spatially-heterodyned hologram and the second spatially-heterodyned hologram.
Recording multiple spatially-heterodyned direct to digital holograms in one digital image
Hanson, Gregory R [Clinton, TN; Bingham, Philip R [Knoxville, TN
2008-03-25
Systems and methods are described for recording multiple spatially-heterodyned direct to digital holograms in one digital image. A method includes digitally recording, at a first reference beam-object beam angle, a first spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; Fourier analyzing the recorded first spatially-heterodyned hologram by shifting a first original origin of the recorded first spatially-heterodyned hologram to sit on top of a first spatial-heterodyne carrier frequency defined by the first reference beam-object beam angle; digitally recording, at a second reference beam-object beam angle, a second spatially-heterodyned hologram including spatial heterodyne fringes for Fourier analysis; Fourier analyzing the recorded second spatially-heterodyned hologram by shifting a second original origin of the recorded second spatially-heterodyned hologram to sit on top of a second spatial-heterodyne carrier frequency defined by the second reference beam-object beam angle; applying a first digital filter to cut off signals around the first original origin and define a first result; performing a first inverse Fourier transform on the first result; applying a second digital filter to cut off signals around the second original origin and define a second result; and performing a second inverse Fourier transform on the second result, wherein the first reference beam-object beam angle is not equal to the second reference beam-object beam angle and a single digital image includes both the first spatially-heterodyned hologram and the second spatially-heterodyned hologram.
Theory and procedures for finding a correct kinetic model for the bacteriorhodopsin photocycle.
Hendler, R W; Shrager, R; Bose, S
2001-04-26
In this paper, we present the implementation and results of new methodology based on linear algebra. The theory behind these methods is covered in detail in the Supporting Information, available electronically (Shragerand Hendler). In brief, the methods presented search through all possible forward sequential submodels in order to find candidates that can be used to construct a complete model for the BR-photocycle. The methodology is limited only to forward sequential models. If no such models are compatible with the experimental data,none will be found. The procedures apply objective tests and filters to eliminate possibilities that cannot be correct, thus cutting the total number of candidate sequences to be considered. In the current application,which uses six exponentials, the total sequences were cut from 1950 to 49. The remaining sequences were further screened using known experimental criteria. The approach led to a solution which consists of a pair of sequences, one with 5 exponentials showing BR* f L(f) M(f) N O BR and the other with three exponentials showing BR* L(s) M(s) BR. The deduced complete kinetic model for the BR photocycle is thus either a single photocycle branched at the L intermediate or a pair of two parallel photocycles. Reasons for preferring the parallel photocycles are presented. Synthetic data constructed on the basis of the parallel photocycles were indistinguishable from the experimental data in a number of analytical tests that were applied.
Ercoli, Carlo; Rotella, Mario; Funkenbusch, Paul D; Russell, Scott; Feng, Changyong
2009-04-01
Standards to test the cutting efficiency of dental rotary cutting instruments are either nonexistent or inappropriate, and knowledge of the factors that affect their cutting performance is limited. Therefore, rotary cutting instruments for crown preparation are generally marketed with weak or unsupported claims of superior performance. The purpose of this study was to examine the cutting behavior of a wide selection of rotary cutting instruments under carefully controlled and reproducible conditions with an air-turbine handpiece. Ten groups of rotary cutting instruments (n=30) designed for tooth preparation were selected: 9 diamond rotary cutting instruments (7 multi-use, 2 disposable) and 1 carbide bur. One bur per group was imaged with a scanning electron microscope (SEM) at different magnifications. Macor blocks (n=75) were used as a substrate, and 4 cuts were made on each specimen, using a new rotary cutting instrument each time, for a total of 300 cuts. The cuts were performed with an air-turbine handpiece (Midwest Quiet Air). A computer-controlled, custom-made testing apparatus was used to monitor all sensors and control the cutting action. The data were analyzed to compare the correlation of rotary cutting instrument type, grit, amount of pressure, cutting rate, revolutions per minute (rpm), temperature, and type of handpiece, using 1-way ANOVA and Tukey's Studentized Range test (alpha=.05). Compared to the baseline temperature, all rotary cutting instruments showed a reduction of temperature in the simulated pulp chamber. The Great White Ultra (carbide bur) showed a significantly higher rate of advancement (0.15 mm/s) and lower applied load (106.46 g) and rpm (304,375.97). Tooth preparation with an adequate water flow does not cause harmful temperature changes in the pulp chamber, regardless of rotary cutting instrument type. The tested carbide bur showed greater cutting efficiency than all diamond rotary cutting instruments.
Probabilistic inversion with graph cuts: Application to the Boise Hydrogeophysical Research Site
NASA Astrophysics Data System (ADS)
Pirot, Guillaume; Linde, Niklas; Mariethoz, Grégoire; Bradford, John H.
2017-02-01
Inversion methods that build on multiple-point statistics tools offer the possibility to obtain model realizations that are not only in agreement with field data, but also with conceptual geological models that are represented by training images. A recent inversion approach based on patch-based geostatistical resimulation using graph cuts outperforms state-of-the-art multiple-point statistics methods when applied to synthetic inversion examples featuring continuous and discontinuous property fields. Applications of multiple-point statistics tools to field data are challenging due to inevitable discrepancies between actual subsurface structure and the assumptions made in deriving the training image. We introduce several amendments to the original graph cut inversion algorithm and present a first-ever field application by addressing porosity estimation at the Boise Hydrogeophysical Research Site, Boise, Idaho. We consider both a classical multi-Gaussian and an outcrop-based prior model (training image) that are in agreement with available porosity data. When conditioning to available crosshole ground-penetrating radar data using Markov chain Monte Carlo, we find that the posterior realizations honor overall both the characteristics of the prior models and the geophysical data. The porosity field is inverted jointly with the measurement error and the petrophysical parameters that link dielectric permittivity to porosity. Even though the multi-Gaussian prior model leads to posterior realizations with higher likelihoods, the outcrop-based prior model shows better convergence. In addition, it offers geologically more realistic posterior realizations and it better preserves the full porosity range of the prior.
Smale, Kenneth B; Potvin, Brigitte M; Shourijeh, Mohammad S; Benoit, Daniel L
2017-09-06
The recent development of a soft tissue artifact (STA) suppression method allows us to re-evaluate the tibiofemoral kinematics currently linked to non-contact knee injuries. The purpose of this study was therefore to evaluate knee joint kinematics and kinetics in six degrees of freedom (DoF) during the loading phases of a jump lunge and side cut using this in silico method. Thirty-five healthy adults completed these movements and their surface marker trajectories were then scaled and processed with OpenSim's inverse kinematics (IK) and inverse dynamics tools. Knee flexion angle-dependent kinematic constraints defined based on previous bone pin (BP) marker trajectories were then applied to the OpenSim model during IK and these constrained results were then processed with the standard inverse dynamics tool. Significant differences for all hip, knee, and ankle DoF were observed after STA suppression for both the jump lunge and side cut. Using clinically relevant effect size estimates, we conclude that STA contamination had led to misclassifications in hip transverse plane angles, knee frontal and transverse plane angles, medial/lateral and distractive/compressive knee translations, and knee frontal plane moments between the NoBP and the BP IK solutions. Our results have substantial clinical implications since past research has used joint kinematics and kinetics contaminated by STA to identify risk factors for musculoskeletal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Boy, M.; Yaşar, N.; Çiftçi, İ.
2016-11-01
In recent years, turning of hardened steels has replaced grinding for finishing operations. This process is compared to grinding operations; hard turning has higher material removal rates, the possibility of greater process flexibility, lower equipment costs, and shorter setup time. CBN or ceramic cutting tools are widely used hard part machining. For successful application of hard turning, selection of suitable cutting parameters for a given cutting tool is an important step. For this purpose, an experimental investigation was conducted to determine the effects of cutting tool edge geometry, feed rate and cutting speed on surface roughness and resultant cutting force in hard turning of AISI H13 steel with ceramic cutting tools. Machining experiments were conducted in a CNC lathe based on Taguchi experimental design (L16) in different levels of cutting parameters. In the experiments, a Kistler 9257 B, three cutting force components (Fc, Ff and Fr) piezoelectric dynamometer was used to measure cutting forces. Surface roughness measurements were performed by using a Mahrsurf PS1 device. For statistical analysis, analysis of variance has been performed and mathematical model have been developed for surface roughness and resultant cutting forces. The analysis of variance results showed that the cutting edge geometry, cutting speed and feed rate were the most significant factors on resultant cutting force while the cutting edge geometry and feed rate were the most significant factor for the surface roughness. The regression analysis was applied to predict the outcomes of the experiment. The predicted values and measured values were very close to each other. Afterwards a confirmation tests were performed to make a comparison between the predicted results and the measured results. According to the confirmation test results, measured values are within the 95% confidence interval.
Logging costs and cutting methods in young-growth ponderosa pine in California
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...
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...
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...
Effects of Ultrasonics-Assisted Face Milling on Surface Integrity and Fatigue Life of Ni-Alloy 718
NASA Astrophysics Data System (ADS)
Suárez, Alfredo; Veiga, Fernando; de Lacalle, Luis N. López; Polvorosa, Roberto; Lutze, Steffen; Wretland, Anders
2016-11-01
This work investigates the effects of ultrasonic vibration-assisted milling on important aspects such us material surface integrity, tool wear, cutting forces and fatigue resistance. As an alternative to natural application of ultrasonic milling in brittle materials, in this study, ultrasonics have been applied to a difficult-to-cut material, Alloy 718, very common in high-temperature applications. Results show alterations in the sub-superficial part of the material which could influence fatigue resistance of the material, as it has been observed in a fatigue test campaign of specimens obtained with the application of ultrasonic milling in comparison with another batch obtained applying conventional milling. Tool wear pattern was found to be very similar for both milling technologies, concluding the study with the analysis of cutting forces, exhibiting certain improvement in case of the application of ultrasonic milling with a more stable evolution.
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
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.
Method for automated building of spindle thermal model with use of CAE system
NASA Astrophysics Data System (ADS)
Kamenev, S. V.
2018-03-01
The spindle is one of the most important units of the metal-cutting machine tool. Its performance is critical to minimize the machining error, especially the thermal error. Various methods are applied to improve the thermal behaviour of spindle units. One of the most important methods is mathematical modelling based on the finite element analysis. The most common approach for its realization is the use of CAE systems. This approach, however, is not capable to address the number of important effects that need to be taken into consideration for proper simulation. In the present article, the authors propose the solution to overcome these disadvantages using automated thermal model building for the spindle unit utilizing the CAE system ANSYS.
Lack of harmonization in sweat testing for cystic fibrosis - a national survey.
Christiansen, Anne Lindegaard; Nybo, Mads
2014-11-01
Sweat testing is used in the diagnosis of cystic fibrosis. Interpretation of the sweat test depends, however, on the method performed since conductivity, osmolality and chloride concentration all can be measured as part of a sweat test. The aim of this study was to investigate how performance of the test is organized in Denmark. Departments conducting the sweat test were contacted and interviewed following a premade questionnaire. They were asked about methods performed, applied NPU (Nomenclature for Properties and Units) code, reference interval, recommended interpretation and referred literature. 14 departments performed the sweat test. One department measured chloride and sodium concentration, while 13 departments measured conductivity. One department used a non-existing NPU code, two departments applied NPU codes inconsistent with the method performed, four departments applied no NPU code and seven applied a correct NPU code. Ten of the departments measuring conductivity applied reference intervals. Nine departments measuring conductivity had recommendations of a normal area, a grey zone and a pathological value, while four departments only applied a normal and grey zone or a pathological value. Cut-off values for normal, grey and pathological areas were like the reference intervals inconsistent. There is inconsistent use of NPU codes, reference intervals and interpretation of sweat conductivity used in the process of diagnosing cystic fibrosis. Because diagnosing cystic fibrosis is a combined effort between local pediatric departments, biochemical and genetic departments and cystic fibrosis centers, a national harmonization is necessary to assure correct clinical use.
Cha, Jungwon; Farhangi, Mohammad Mehdi; Dunlap, Neal; Amini, Amir A
2018-01-01
We have developed a robust tool for performing volumetric and temporal analysis of nodules from respiratory gated four-dimensional (4D) CT. The method could prove useful in IMRT of lung cancer. We modified the conventional graph-cuts method by adding an adaptive shape prior as well as motion information within a signed distance function representation to permit more accurate and automated segmentation and tracking of lung nodules in 4D CT data. Active shape models (ASM) with signed distance function were used to capture the shape prior information, preventing unwanted surrounding tissues from becoming part of the segmented object. The optical flow method was used to estimate the local motion and to extend three-dimensional (3D) segmentation to 4D by warping a prior shape model through time. The algorithm has been applied to segmentation of well-circumscribed, vascularized, and juxtapleural lung nodules from respiratory gated CT data. In all cases, 4D segmentation and tracking for five phases of high-resolution CT data took approximately 10 min on a PC workstation with AMD Phenom II and 32 GB of memory. The method was trained based on 500 breath-held 3D CT data from the LIDC data base and was tested on 17 4D lung nodule CT datasets consisting of 85 volumetric frames. The validation tests resulted in an average Dice Similarity Coefficient (DSC) = 0.68 for all test data. An important by-product of the method is quantitative volume measurement from 4D CT from end-inspiration to end-expiration which will also have important diagnostic value. The algorithm performs robust segmentation of lung nodules from 4D CT data. Signed distance ASM provides the shape prior information which based on the iterative graph-cuts framework is adaptively refined to best fit the input data, preventing unwanted surrounding tissue from merging with the segmented object. © 2017 American Association of Physicists in Medicine.
Method of measuring material properties of rock in the wall of a borehole
Overmier, David K.
1985-01-01
To measure the modulus of elasticity of the rock in the wall of a borehole, a plug is cut in the borehole wall. The plug, its base attached to the surrounding rock, acts as a short column in response to applied forces. A loading piston is applied to the top of the plug and compression of the plug is measured as load is increased. Measurement of piston load and plug longitudinal deformation are made to determine the elastic modulus of the plug material. Poisson's ratio can be determined by simultaneous measurements of longitudinal and lateral deformation of the plug in response to loading. To determine shear modulus, the top of the plug is twisted while measurements are taken of torsional deformation.
Method of measuring material properties of rock in the wall of a borehole
Overmier, D.K.
1984-01-01
To measure the modulus of elasticity of the rock in the wall of a borehole, a plug is cut in the borehole wall. The plug, its base attached to the surrounding rock, acts as a short column in response to applied forces. A loading piston is applied to the top of the plug and compression of the plug is measured as load is increased. Measurements of piston load and plug longitudinal deformation are made to determine the elastic modulus of the plug material. Poisson's ratio can be determined by simultaneous measurements of longitudinal and lateral deformation of the plug in response to loading. To determine shear modulus, the top of the plug is twisted while measurements are taken of torsional deformation.
Selective Coupling Enhances Harmonic Generation of Whispering-Gallery Modes
NASA Astrophysics Data System (ADS)
Trainor, Luke S.; Sedlmeir, Florian; Peuntinger, Christian; Schwefel, Harald G. L.
2018-02-01
We demonstrate second-harmonic generation (SHG) in an x -cut congruent lithium niobate (LN) whispering-gallery mode (WGM) resonator. First, we show theoretically that independent control of the coupling of the pump and signal modes is optimal for high conversion rates. A coupling scheme based on our earlier work [F. Sedlmeir et al., Phys. Rev. Applied 7, 024029 (2017), 10.1103/PhysRevApplied.7.024029] is then implemented experimentally to verify this improvement. Thereby, we are able to improve on the efficiency of SHG by more than an order of magnitude by selectively outcoupling using a LN prism, utilizing the birefringence of it and the resonator in kind. This method is also applicable to other nonlinear processes in WGM resonators.
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.
Desalination of Walls and Façades
NASA Astrophysics Data System (ADS)
Wedekind, W.; Jáuregui Arreola, K.; Siegesmund, S.
2012-04-01
For large monumental objects like walls and façades, the common technique of applying poultices for desalination often are not effective. This practice is neither cost effective nor does it lead to the desired result of desalination. To manage the conservation and desalination of these kinds of objects, several sprinkling techniques are known and have been applied on historical objects. For example, in the wooden warship Vasa, which was excavated from the sea bottom in Stockholm/Sweden, a sprinkling method was applied in 1961 for conservation and desalination. A sprinkling method to desalinate porous mineral materials will be presented using three different case studies: the rock cut monument no. 825 in Petra/Jordan, the medieval monastary church of the former Franziscan convent in Zeitz/Germany and the baroque monastary church Santa Monica in Guadalajara/Mexico. Before to start with practical conservation, the material- and petropysical properties, focoussed on water transport properties, like porosity, pore size distribution, water uptake and drying rate were investigadet. Diagnostic investigations on the objects included the mapping of deterioration, moister content measurements and salt accumulation determined by borehole cuts samples at depth. In the sprinkling method water is sprayed onto the wall surface through nozzels arranged in a modular grid. Depending on the sprinkling duration, a small or a large amount of water seeps into the porous materials, whereby the depth penetration can be adjusted accordingly. The water not absorbed by the stone runs off the facade and can be collected in liter amounts and tested by electrical conductivity with respect to the dissolved substances. After the drying of the wall's surface and the accumulation of salt at the material's surface, the procedure is repeated. For each subsequent washing a lower content of salt should be brought to the surface. Step by step the salt concentration will eventually decrease to almost zero. By application of the sprinkling method several thousand grams of soluble salts can be extracted. A significant reduction of the salt content within the stone can be detected by drilling dust analyses. The specific situation of salt-accumulation and weathering will be illustrated in each case, along with a presentation of the results and the difficulties and experiences of practical desalination.
NASA Astrophysics Data System (ADS)
Marghany, Maged; Ibrahim, Zelina; Van Genderen, Johan
2002-11-01
The present work is used to operationalize the azimuth cut-off concept in the study of significant wave height. Three ERS-1 images have been used along the coastal waters of Terengganu, Malaysia. The quasi-linear transform was applied to map the SAR wave spectra into real ocean wave spectra. The azimuth cut-off was then used to model the significant wave height. The results show that azimuth cut-off varied with the different period of the ERS-1 images. This is because of the fact that the azimuth cut-off is a function of wind speed and significant wave height. It is of interest to find that the significant wave height modeled from azimuth cut-off is in good relation with ground wave conditions. It can be concluded that ERS-1 can be used as a monitoring tool in detecting the significant wave height variation. The azimuth cut-off can be used to model the significant wave height. This means that the quasi-linear transform could be a good application to significant wave height variation during different seasons.
Experimental Investigation of Multi-mode Fiber Laser Cutting of Cement Mortar.
Lee, Dongkyoung; Pyo, Sukhoon
2018-02-10
This study successfully applied multi-mode laser cutting with the variation of the laser cutting speed to cement mortar for the first time. The effects of the amount of silica sand in the cement mortar on laser cutting are tested and analyzed. The kerf width and penetration depth of the specimens after laser cutting are investigated. As the laser cutting speed increases, the penetration depth decreases for both cement paste and cement mortar, whereas the kerf width becomes saturated and increases, respectively, for cement paste and cement mortar. Cross sections of the specimens are compared with illustrations. Top-view images of the cement mortar with indicators of the physical characteristics, such as re-solidification, burning, and cracks are examined, and the possible causes of these characteristics are explained. The optical absorption rates of cement-based materials are quantified at wide ranges of wavelength to compare the absorption rates in accordance with the materials compositions. The chemical composition variation before and after laser cutting is also compared by EDX (Energy Dispersive X-Ray) analysis. In addition to these observations, material removal mechanisms for cement mortar are proposed.
Experimental Investigation of Multi-mode Fiber Laser Cutting of Cement Mortar
2018-01-01
This study successfully applied multi-mode laser cutting with the variation of the laser cutting speed to cement mortar for the first time. The effects of the amount of silica sand in the cement mortar on laser cutting are tested and analyzed. The kerf width and penetration depth of the specimens after laser cutting are investigated. As the laser cutting speed increases, the penetration depth decreases for both cement paste and cement mortar, whereas the kerf width becomes saturated and increases, respectively, for cement paste and cement mortar. Cross sections of the specimens are compared with illustrations. Top-view images of the cement mortar with indicators of the physical characteristics, such as re-solidification, burning, and cracks are examined, and the possible causes of these characteristics are explained. The optical absorption rates of cement-based materials are quantified at wide ranges of wavelength to compare the absorption rates in accordance with the materials compositions. The chemical composition variation before and after laser cutting is also compared by EDX (Energy Dispersive X-Ray) analysis. In addition to these observations, material removal mechanisms for cement mortar are proposed. PMID:29439431
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cremonesi, Matteo
In the frame of the strong on-going data analysis effort of the CDF collaboration at Fermilab, a method was developed by the candidate to improve the background rejection efficiency in the search for associated pair production of electroweak W, Z bosons. The performaces of the method for vetoing the tt background in a WZ/ZZ → fνqmore » $$\\bar{q}$$ diboson search are reported. The method was developed in the inclusive 2-jets sample and applied to the “tag-2 jets" region, the subsample defined by the request that the two jets carry beauty flavor. In this region the tt production is one of the largest backgrounds. The tt veto proceeds in two steps: first, a set of pre-selection cuts are applied in a candidate sample where up to two leptons are accepted in addition to a jet pair, and the ZZ component of the signal is thus preserved; next, a Neural Network is trained to indicate the probability that the event be top-pair production. To validate the the method as developed in the inclusive 2-jets sample, it is applied to veto region providing a significant rejection of this important background.« less
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.
Autoresonant control of nonlinear mode in ultrasonic transducer for machining applications.
Babitsky, V I; Astashev, V K; Kalashnikov, A N
2004-04-01
Experiments conducted in several countries have shown that the improvement of machining quality can be promoted through conversion of the cutting process into one involving controllable high-frequency vibration at the cutting zone. This is achieved through the generation and maintenance of ultrasonic vibration of the cutting tool to alter the fracture process of work-piece material cutting to one in which loading of the materials at the tool tip is incremental, repetitive and controlled. It was shown that excitation of the high-frequency vibro-impact mode of the tool-workpiece interaction is the most effective way of ultrasonic influence on the dynamic characteristics of machining. The exploitation of this nonlinear mode needs a new method of adaptive control for excitation and stabilisation of ultrasonic vibration known as autoresonance. An approach has been developed to design an autoresonant ultrasonic cutting unit as an oscillating system with an intelligent electronic feedback controlling self-excitation in the entire mechatronic system. The feedback produces the exciting force by means of transformation and amplification of the motion signal. This allows realisation for robust control of fine resonant tuning to bring the nonlinear high Q-factor systems into technological application. The autoresonant control provides the possibility of self-tuning and self-adaptation mechanisms for the system to keep the nonlinear resonant mode of oscillation under unpredictable variation of load, structure and parameters. This allows simple regulation of intensity of the process whilst keeping maximum efficiency at all times. An autoresonant system with supervisory computer control was developed, tested and used for the control of the piezoelectric transducer during ultrasonically assisted cutting. The system has been developed as combined analog-digital, where analog devices process the control signal, and parameters of the devices are controlled digitally by computer. The system was applied for advanced machining of aviation materials.
Restoration guidelines for riparian areas using dormant stock "pole" cuttings
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.
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.
Edinburgh Working Papers in Applied Linguistics, Number 4.
ERIC Educational Resources Information Center
Davies, Alan
1993-01-01
"Edinburgh Working Papers" is intended to show a yearly cross-section of current work in Edinburgh's Department of Applied Linguistics and to elicit reactions and criticism. Articles in this volume include the following: "MSC Common Room Conversations: Topics and Terms" (Joan Cutting); "Speculation and Empiricism in Applied Linguistics" (Alan…
Edinburgh Working Papers in Applied Linguistics. Number 5.
ERIC Educational Resources Information Center
Davies, Alan, Ed.; Parkinson, Brian, Ed.
1994-01-01
The eight papers in this volume, prepared by staff and students of the Institute for Applied Language Studies of Edinburgh University, address a variety of issues in applied linguistics. The papers include: (1) "A Coding System for Analyzing a Spoken Database" (Joan Cutting); (2) "L2 Perceptual Acquisition: The Effect of…
Foreign Object Damage to Tires Operating in a Wartime Environment
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.
Automatic extraction of discontinuity orientation from rock mass surface 3D point cloud
NASA Astrophysics Data System (ADS)
Chen, Jianqin; Zhu, Hehua; Li, Xiaojun
2016-10-01
This paper presents a new method for extracting discontinuity orientation automatically from rock mass surface 3D point cloud. The proposed method consists of four steps: (1) automatic grouping of discontinuity sets using an improved K-means clustering method, (2) discontinuity segmentation and optimization, (3) discontinuity plane fitting using Random Sample Consensus (RANSAC) method, and (4) coordinate transformation of discontinuity plane. The method is first validated by the point cloud of a small piece of a rock slope acquired by photogrammetry. The extracted discontinuity orientations are compared with measured ones in the field. Then it is applied to a publicly available LiDAR data of a road cut rock slope at Rockbench repository. The extracted discontinuity orientations are compared with the method proposed by Riquelme et al. (2014). The results show that the presented method is reliable and of high accuracy, and can meet the engineering needs.
Kim, Yong-Ho; Park, Dongho; Hwang, Jungho; Kim, Yong-Jun
2009-09-21
Conventional virtual impactors experience a large pressure drop when they classify particles according to size, in particular ultrafine particles smaller than 100 nm in diameter. Therefore, most virtual impactors have been used to classify particles larger than 100 nm. Their cut-off diameters are also fixed by the geometry of their flow channels. In the proposed virtual impactor, particles smaller than 100 nm are accelerated by applying DC potentials to an integrated electrode pair. By the electrical acceleration, the large pressure drop could be significantly decreased and new cut-off diameters smaller than 100 nm could be successfully added. The geometric cut-off diameter (GCD) of the proposed virtual impactor was designed to be 1.0 microm. Performances including the GCD and wall loss were examined by classifying dioctyl sebacate of 100 to 600 nm in size and carbon particles of 0.6 to 10 microm in size. The GCD was measured to be 0.95 microm, and the wall loss was highest at 1.1 microm. To add new cut-off diameters, monodisperse NaCl particles ranging from 15 to 70 nm were classified using the proposed virtual impactor with applying a DC potential of 0.25 to 3.0 kV. In this range of the potential, the new cut-off diameters ranging from 15 to 35 nm was added.
The eminent need for an academic program in universities to teach nanomedicine.
Vélez, Juan Manuel; Vélez, Juan Jesus
2011-01-01
Nanomedicine is on the cutting edge of technology applied to medical and biological sciences. Nanodevices, nanomaterials, nanoinstruments, nanotechnologies, and nanotechniques (laboratory methods and procedures) are important for the modern practice of medicine and essential for research that could stimulate the discovery of new medical advances. Accordingly, there is an eminent need for implementing an academic program in universities to teach this indispensable and pragmatic discipline, especially in the departments of graduate studies and research in the areas of pharmacology, genetic engineering, proteomics, and molecular and cellular biology.
Signature of Strange Dibaryon in Kaon-Induced Reaction
NASA Astrophysics Data System (ADS)
Ohnishi, Shota; Ikeda, Yoichi; Kamano, Hiroyuki; Sato, Toru
2013-03-01
We examine how the signature of the strange-dibaryon resonances in the {bar{K}NN} - πΣ N system shows up in the scattering amplitude on the physical real energy axis within the framework of Alt-Grassberger-Sandhas equations. The so-called point method is applied to handle the three-body unitarity cut in the amplitudes. We also discuss the possibility that the strange-dibaryon production reactions can be used for discriminating between existing models of the two-body {bar{K}N} - πΣ system with Λ(1405).
Cziriak, N B; Szalma, J; Vag, J; Bogdan, S
2016-09-01
The aim of this in vitro study was to compare the effect of sagittal saw handpiece with a piezoelectric device on the rise in intraosseous temperature and on the preparation time. 100 native pieces of pork ribs were cut either with S-8 S handpiece connected to Elcomed surgical motor (W&H) (n = 30) or with B6 insert connected to Piezomed (W&H) using continuous movement (n = 30) or with B6 using short breaks to perform intermittent cutting (n = 30). The rest were cut either by S-8 S (n = 5) or by B6 (n = 5) both applied by permanent pressure. The intraosseous temperature was measured by K-type thermocouple connected to digital thermometer placed in the bone 1 mm away of the cutting line. The heat generated and the time of the complete cutting were recorded. In S-8 S group the temperature never rose above 47⁰C. Using the B6 with permanent movement the critical temperature was reached in 16.2 ± 3.53% of the cases while taking breaks decreased the results to 2.6 ? 0.96% (p <0.001). In no cases the temperature elevation above 4700 lasted more than 60 sec. Applying the B6 by permanent pressure resulted in heat up to 90.3⁰C. Our results suggest that piezoelectric device could use safely according to the factory instructions, however further reduce of heat load could be achieved if the intermittent cutting motion combined with short-time cooling periods.
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.
2012-01-01
Background Staphylococcus aureus is one of the most common causes of intramammary infections in dairy cows at dry off. Reliable identification is important for disease management on herd level and for antimicrobial treatment of infected animals. Our objective was to evaluate the test characteristics of PathoProof ™ Mastitis PCR Assay and bacteriological culture (BC) in diagnosing bovine intramammary infections caused by S. aureus at dry off at different PCR cycle threshold (Ct)-value cut-offs. Methods Sterile quarter samples and non-sterile composite samples from 140 animals in seven herds were collected in connection with the dairy herd improvement (DHI) milk recording. All quarter samples were analyzed using BC whereas all composite samples were analyzed with PathoProof ™ Mastitis PCR Assay. Latent class analysis was used to estimate test properties for PCR and BC in the absence of a perfect reference test. The population was divided into two geographically divided subpopulations and the Hui-Walter 2-test 2-populations model applied to estimate Se, Sp for the two tests, and prevalence for the two subpopulations. Results The Se for PCR increased with increasing Ct-value cut-off, accompanied by a small decrease in Sp. For BC the Se decreased and Sp increased with increasing Ct-value cut-off. Most optimal test estimates for the real-time PCR assay were at a Ct-value cut-off of 37; 0.93 [95% posterior probability interval (PPI) 0.60-0.99] for Se and 0.95 [95% PPI 0.95-0.99] for Sp. At the same Ct-value cut-off, Se and Sp for BC were 0.83 [95% PPI 0.66-0.99] and 0.97 [95% PPI 0.91-0.99] respectively. Depending on the chosen PCR Ct-value cut-off, the prevalence in the subpopulations varied; the prevalence increased with increasing PCR Ct-value cut-offs. Conclusion Neither BC nor real-time PCR is a perfect test in detecting IMI in dairy cows at dry off. The changes in sensitivity and prevalence at different Ct-value cut-offs for both PCR and BC may indicate a change in the underlying disease definition. At low PCR Ct-value cut-offs the underlying disease definition may be a truly/heavily infected cow, whereas at higher PCR Ct-value cut-offs the disease definition may be a S. aureus positive cow. PMID:23164432
Liver vessels segmentation using a hybrid geometrical moments/graph cuts method
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
Effect of Moisture Content of Paper Material on Laser Cutting
NASA Astrophysics Data System (ADS)
Stepanov, Alexander; Saukkonen, Esa; Piili, Heidi; Salminen, Antti
Laser technology has been used in industrial processes for several decades. The most advanced development and implementation took place in laser welding and cutting of metals in automotive and ship building industries. However, there is high potential to apply laser processing to other materials in various industrial fields. One of these potential fields could be paper industry to fulfill the demand for high quality, fast and reliable cutting technology. Difficulties in industrial application of laser cutting for paper industry are associated to lack of basic information, awareness of technology and its application possibilities. Nowadays possibilities of using laser cutting for paper materials are widened and high automation level of equipment has made this technology more interesting for manufacturing processes. Promising area of laser cutting application at paper making machines is longitudinal cutting of paper web (edge trimming). There are few locations at a paper making machine where edge trimming is usually done: wet press section, calender or rewinder. Paper web is characterized with different moisture content at different points of the paper making machine. The objective of this study was to investigate the effect of moisture content of paper material on laser cutting parameters. Effect of moisture content on cellulose fibers, laser absorption and energy needed for cutting is described as well. Laser cutting tests were carried out using CO2 laser.
Ophthalmic method and apparatus
NASA Technical Reports Server (NTRS)
Evvard, J. C.; Mcgannon, W. J.; Vargo, D. J. (Inventor)
1973-01-01
A method and apparatus for removing material and components such as the lens from an eye is described. High speed rotary cutting members at one end of a rod macerate the lens while an annular tubing disposed around the cutting members vibrates ultrasonically to coact with the cutting members in macerating the lens. At the same time, a liquid is supplied to the chamber behind the cornea of the eye. Spiral grooves extending along the rotating rod from the cutting members evacuate the liquid and the macerated material from the eye. An alternate embodiment of the apparatus includes a tube through which liquid is supplied to the operative site of the ultrasonically vibrating tube and the cutting members in the area of the lens.
Zhang, Junhua; Wang, Yuanyuan; Shi, Xinling
2009-12-01
A modified graph cut was proposed under the elliptical shape constraint to segment cervical lymph nodes on sonograms, and its effect on the measurement of short axis to long axis ratio (S/L) was investigated by using the relative ultimate measurement accuracy (RUMA). Under the same user inputs, the proposed algorithm successfully segmented all 60 sonograms tested, while the traditional graph cut failed. The mean RUMA resulted from the developed method was comparable to that resulted from the manual segmentation. Results indicated that utilizing the elliptical shape prior could appreciably improve the graph cut for nodes segmentation, and the proposed method satisfied the accuracy requirement of S/L measurement.
NASA Astrophysics Data System (ADS)
David, M.; Roche, R.; Mattsson, M.; Sutton, M. A.; Dämmgen, U.; Schjoerring, J. K.; Cellier, P.
2009-01-01
Grassland management may lead to strong modification of the canopy structure and hence fluxes of carbon and nitrogen in the soil-plant-atmosphere system. Mowing or grazing removes green leaves, which are often a sink for ammonia. Consequently, the ratio between actively growing leaves and senescing/dead parts of the plants is strongly changed in favour of the latter, which may constitute a large source of ammonia. Moreover, fertilisers are a known source of ammonia through direct volatilisation. The effects of grassland management, e.g. growing, cutting and fertilisation, on ammonia emission were investigated using a dynamic chamber. This technique made it possible to monitor ammonia emissions in the field at the plant level. With ammonia-free air at the inlet, the ammonia emissions from mature sward did not exceed 4 ng NH3 m-2 s-1. They were approximately 20 times larger above a sward re-growing after cutting and 200 times larger after fertilisation, where 0.5-1.0% of the applied inorganic nitrogen fertiliser was lost by volatilisation. Cutting implied three main changes in ammonia sources and sinks within the canopy: (i) physiological changes with nitrogen remobilisation to the growing leaves and increase in senescence, (ii) changes in compartment proportions with only 5% of green leaves remaining after cutting as opposed to equal proportions of dead leaves as green leaves before cutting, (iii) microclimate changes within the canopy especially for litter with higher turbulence, temperature, and alternation of dry (day) and wet (night) conditions after cutting. These changes promoted ammonia volatilisation from the litter, which could account for the increased ammonia loss following cutting. Another potential source was the wounded surfaces of the stubble which may have emitted ammonia during bleeding and evaporation of sap containing significant levels of ammonium. These results showed that the contribution of litter and drying cut sward on the ammonia balance of grassland is very significant, as well as their interaction with microclimatic conditions. This could apply to most natural and managed ecosystems and could be especially significant in the former. Consequently, further studies on ammonia fluxes should have a 0focus on this part of the canopy.
A Guide for Setting the Cut-Scores to Minimize Weighted Classification Errors in Test Batteries
ERIC Educational Resources Information Center
Grabovsky, Irina; Wainer, Howard
2017-01-01
In this article, we extend the methodology of the Cut-Score Operating Function that we introduced previously and apply it to a testing scenario with multiple independent components and different testing policies. We derive analytically the overall classification error rate for a test battery under the policy when several retakes are allowed for…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sofu, Tanju; LaChance, Jeffrey L.; Bari, R.
This report proposes potential research priorities for the Department of Energy (DOE) with the intent of improving the licensability of the Sodium Fast Reactor (SFR). In support of this project, five panels were tasked with identifying potential safety-related gaps in available information, data, and models needed to support the licensing of a SFR. The areas examined were sodium technology, accident sequences and initiators, source term characterization, codes and methods, and fuels and materials. It is the intent of this report to utilize a structured and transparent process that incorporates feedback from all interested stakeholders to suggest future funding priorities formore » the SFR research and development. While numerous gaps were identified, two cross-cutting gaps related to knowledge preservation were agreed upon by all panels and should be addressed in the near future. The first gap is a need to re-evaluate the current procedures for removing the Applied Technology designation from old documents. The second cross-cutting gap is the need for a robust Knowledge Management and Preservation system in all SFR research areas. Closure of these and the other identified gaps will require both a reprioritization of funding within DOE as well as a re-evaluation of existing bureaucratic procedures within the DOE associated with Applied Technology and Knowledge Management.« less
Sevik, Hakan; Guney, Kerim
2013-01-01
This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height.
Twice cutting method reduces tibial cutting error in unicompartmental knee arthroplasty.
Inui, Hiroshi; Taketomi, Shuji; Yamagami, Ryota; Sanada, Takaki; Tanaka, Sakae
2016-01-01
Bone cutting error can be one of the causes of malalignment in unicompartmental knee arthroplasty (UKA). The amount of cutting error in total knee arthroplasty has been reported. However, none have investigated cutting error in UKA. The purpose of this study was to reveal the amount of cutting error in UKA when open cutting guide was used and clarify whether cutting the tibia horizontally twice using the same cutting guide reduced the cutting errors in UKA. We measured the alignment of the tibial cutting guides, the first-cut cutting surfaces and the second cut cutting surfaces using the navigation system in 50 UKAs. Cutting error was defined as the angular difference between the cutting guide and cutting surface. The mean absolute first-cut cutting error was 1.9° (1.1° varus) in the coronal plane and 1.1° (0.6° anterior slope) in the sagittal plane, whereas the mean absolute second-cut cutting error was 1.1° (0.6° varus) in the coronal plane and 1.1° (0.4° anterior slope) in the sagittal plane. Cutting the tibia horizontally twice reduced the cutting errors in the coronal plane significantly (P<0.05). Our study demonstrated that in UKA, cutting the tibia horizontally twice using the same cutting guide reduced cutting error in the coronal plane. Copyright © 2014 Elsevier B.V. All rights reserved.
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.
[Study of cuttings identification using laser-induced breakdown spectroscopy].
Tian, Ye; Wang, Zhen-nan; Hou, Hua-ming; Zhai, Xiao-wei; Ci, Xing-hua; Zheng, Rong-er
2012-08-01
Cutting identification is one of the most important links in the course of cutting logging which is very significant in the process of oil drilling. In the present paper, LIBS was used for identification of four kinds of cutting samples coming from logging field, and then multivariate analysis was used in data processing. The whole spectra model and the feature model were built for cuttings identification using PLS-DA method. The accuracy of the whole spectra model was 88.3%, a little more than the feature model with an accuracy of 86.7%. While in the aspect of data size, the variables were decreased from 24,041 to 27 by feature extraction, which increased the efficiency of data processing observably. The obtained results demonstrate that LIBS combined with chemometrics method could be developed as a rapid and valid approach to cutting identification and has great potential to be used in logging field.
Validation of tool mark analysis of cut costal cartilage.
Love, Jennifer C; Derrick, Sharon M; Wiersema, Jason M; Peters, Charles
2012-03-01
This study was designed to establish the potential error rate associated with the generally accepted method of tool mark analysis of cut marks in costal cartilage. Three knives with different blade types were used to make experimental cut marks in costal cartilage of pigs. Each cut surface was cast, and each cast was examined by three analysts working independently. The presence of striations, regularity of striations, and presence of a primary and secondary striation pattern were recorded for each cast. The distance between each striation was measured. The results showed that striations were not consistently impressed on the cut surface by the blade's cutting edge. Also, blade type classification by the presence or absence of striations led to a 65% misclassification rate. Use of the classification tree and cross-validation methods and inclusion of the mean interstriation distance decreased the error rate to c. 50%. © 2011 American Academy of Forensic Sciences.
Cerclage handling for improved fracture treatment. A biomechanical study on the twisting procedure.
Wähnert, D; Lenz, M; Schlegel, U; Perren, S; Windolf, M
2011-01-01
Twisting is clinically the most frequently applied method for tightening and maintaining cerclage fixation. The twisting procedure is controversially discussed. Several factors during twisting affect the mechanical behaviour of the cerclage. This in vitro study investigated the influence of different parameters of the twisting procedure on the fixation strength of the cerclage in an experimental setup with centripetal force application. Cortical half shells of the femoral shaft were mounted on a testing fixture. 1.0 mm, 1.25 mm and 1.5 mm stainless ste- el wire cerclages as well as a 1.0mm cable cerclage were applied to the bone. Pretension of the cerclage during the installation was measured during the locking procedure. Subsequently, cyclic testing was performed up to failure. Higher pretension could be achieved with increasing wire diameter. However, with larger wire diameter the drop of pre- tension due to the bending and cutting the twist also increased. The cable cerclage showed the highest pretension after locking. Cerclages twisted under traction revealed significantly higher initial cerclage tension. Plastically deformed twists offered higher cerclage pretension compared to twists which were deformed in the elastic region of the material. Cutting the wire within the twist caused the highest loss of cerclage tension (44% initial tension) whereas only 11 % was lost when cutting the wire ends separately. The bending direction of the twist significantly influenced the cerclage pretension. 45% pretension was lost in forward bending of the twist, 53% in perpendicular bending and 90% in backward bending. Several parameters affect the quality of a cerclage fixation. Adequate installation of cerclage wires could markedly improve the clinical outcome of cerclage.
Velazquez-Alva, Maria Consuelo; Irigoyen Camacho, Maria Esther; Lazarevich, Irina; Delgadillo Velazquez, Jaime; Acosta Dominguez, Patricia; Zepeda Zepeda, Marco A
2017-01-01
To compare the prevalence of sarcopenia using two indicators: skeletal muscle mass index (SMI) and calf circumference (CC) used in the algorithm proposed by the European Working Group on Sarcopenia in Mexican elderly women. This was a cross-sectional study. Lean body mass was determined by dual-energy X-ray absorptiometry. To define sarcopenia, the SMI was obtained using a cut-off value of 5.5 kg/m 2 , and the CC cut-off was 31 cm. For gait speed and handgrip strength, the cut-off values were 0.8 m/s and 20 kg, respectively. A total of 137 women (mean age 73.8 ± 6.7 years) participated in the study. The prevalence of sarcopenia was 14.6% using SMI and 11.0% using CC (P = 0.009). Body mass index was associated with a lower probability of sarcopenia applying SMI or CC (OR 0.75, P = 0.002 for SMI and OR 0.71, P = 0.004 for CC). Sarcopenia evaluated either with dual-energy X-ray absorptiometry or CC was not associated with physical performance, such as five times chair stand test, timed up and go test and short physical performance battery. Additionally, SMI was not associated with physical performance, five times chair stand test (P = 0.775) and timed up-and-go test (P = 0.341). The prevalence of sarcopenia in active elderly women was low. A higher prevalence of sarcopenia was detected using SMI compared with CC. It is important to identify the best methods to assess skeletal muscle mass to obtain a reliable diagnosis of sarcopenia. Geriatr Gerontol Int 2017; 17: 161-170. © 2015 Japan Geriatrics Society.
Effective increase in beam emittance by phase-space expansion using asymmetric Bragg diffraction.
Chu, Chia-Hung; Tang, Mau-Tsu; Chang, Shih-Lin
2015-08-24
We propose an innovative method to extend the utilization of the phase space downstream of a synchrotron light source for X-ray transmission microscopy. Based on the dynamical theory of X-ray diffraction, asymmetrically cut perfect crystals are applied to reshape the position-angle-wavelength space of the light source, by which the usable phase space of the source can be magnified by over one hundred times, thereby "phase-space-matching" the source with the objective lens of the microscope. The method's validity is confirmed using SHADOW code simulations, and aberration through an optical lens such as a Fresnel zone plate is examined via matrix optics for nano-resolution X-ray images.
Graph-Cut Methods for Grain Boundary Segmentation (Preprint)
2011-06-01
metals and metal alloys ) are among the strongest determinants of many material properties, such as mechanical strength or fracture resistance. In materials...cropped) Ni-based alloy image (a) using normalized cut (b) and ratio cut (c). Similar to normalized cut is the average-cut approach [11], where the...framework [2]. (a) (b) (c) Figure 3: Segmentation of a (cropped) Ni-based alloy image by optimal labeling. (a) Segmented grain bound- aries in a template
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.
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.
EVALUATION OF THE CARBON FOOTPRINT OF AN INNOVATIVE SEWER REHABILITATION METHOD - abstract
A benefit of trenchless methods touted by many practitioners when compared to open cut construction is lower carbon dioxide emissions. In an attempt to verify these claims, tools have been developed that calculate the environmental impact of traditional open cut methods and commo...
EVALUATION OF THE CARBON FOOTPRINT OF AN INNOVATIVE SEWER REHABILITATION METHOD
A benefit of trenchless methods touted by many practitioners when compared to open cut construction is lower carbon dioxide emissions. In an attempt to verify these claims, tools have been developed that calculate the environmental impact of traditional open cut methods and commo...
NASA Astrophysics Data System (ADS)
Shim, Hackjoon; Lee, Soochan; Kim, Bohyeong; Tao, Cheng; Chang, Samuel; Yun, Il Dong; Lee, Sang Uk; Kwoh, Kent; Bae, Kyongtae
2008-03-01
Knee osteoarthritis is the most common debilitating health condition affecting elderly population. MR imaging of the knee is highly sensitive for diagnosis and evaluation of the extent of knee osteoarthritis. Quantitative analysis of the progression of osteoarthritis is commonly based on segmentation and measurement of articular cartilage from knee MR images. Segmentation of the knee articular cartilage, however, is extremely laborious and technically demanding, because the cartilage is of complex geometry and thin and small in size. To improve precision and efficiency of the segmentation of the cartilage, we have applied a semi-automated segmentation method that is based on an s/t graph cut algorithm. The cost function was defined integrating regional and boundary cues. While regional cues can encode any intensity distributions of two regions, "object" (cartilage) and "background" (the rest), boundary cues are based on the intensity differences between neighboring pixels. For three-dimensional (3-D) segmentation, hard constraints are also specified in 3-D way facilitating user interaction. When our proposed semi-automated method was tested on clinical patients' MR images (160 slices, 0.7 mm slice thickness), a considerable amount of segmentation time was saved with improved efficiency, compared to a manual segmentation approach.
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.
Heshka, Nicole E.; Hager, Darcy B.
2015-01-01
A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate interferences, a two dimensional column configuration is used, with a Deans switch employed to transfer hydrogen sulfide from the first to the second column (heart-cutting). Liquid crude samples are first separated on a dimethylpolysiloxane column, and light gases are heart-cut and further separated on a bonded porous layer open tubular (PLOT) column that is able to separate hydrogen sulfide from other light sulfur species. Hydrogen sulfide is then detected with a sulfur chemiluminescence detector, adding an additional layer of selectivity. Following separation and detection of hydrogen sulfide, the system is backflushed to remove the high-boiling hydrocarbons present in the crude samples and to preserve chromatographic integrity. Dissolved hydrogen sulfide has been quantified in liquid samples from 1.1 to 500 ppm, demonstrating wide applicability to a range of samples. The method has also been successfully applied for the analysis of gas samples from crude oil headspace and process gas bags, with measurement from 0.7 to 9,700 ppm hydrogen sulfide. PMID:26709594
Research on NC laser combined cutting optimization model of sheet metal parts
NASA Astrophysics Data System (ADS)
Wu, Z. Y.; Zhang, Y. L.; Li, L.; Wu, L. H.; Liu, N. B.
2017-09-01
The optimization problem for NC laser combined cutting of sheet metal parts was taken as the research object in this paper. The problem included two contents: combined packing optimization and combined cutting path optimization. In the problem of combined packing optimization, the method of “genetic algorithm + gravity center NFP + geometric transformation” was used to optimize the packing of sheet metal parts. In the problem of combined cutting path optimization, the mathematical model of cutting path optimization was established based on the parts cutting constraint rules of internal contour priority and cross cutting. The model played an important role in the optimization calculation of NC laser combined cutting.
García Páez, J M; Jorge Herrero, E; Rocha, A; Martín-Maestro, M; Castillo-Olivares, J L; Millán, I; Carrera Sanmartín, A; Cordón, A
2002-10-01
Ostrich pericardium, sutured using a telescoping or overlapping technique, was studied to determine its mechanical behavior. From each of 12 pericardial sacs, four contiguous strips were cut longitudinally, from root to apex, and another four contiguous strips were cut in transverse direction. One of the strips in each set of four was used as an unsutured control and the remaining three were sutured by overlapping 0.5 cm of the tissue and sewing with Gore-tex, Prolene or Pronova. These 96 samples were then subjected to tensile testing along their major axes until rupture. The tensile stresses recorded in the suture materials at the moment tears appeared in the pericardium ranged between 55.99 MPa and 70.23 MPa for Gore-tex in samples cut in the two directions. Shear stress became ostensible at 56 MPa, with clearly evident tears. However, microfracture of the collagen fibers must be produced at much lower stress levels. The comparison of the resistance in kilograms (machine-imposed), without taking into account the sections in which the load was applied, demonstrated only a slight loss of load when the telescoping suture was employed in ostrich pericardium samples. Ostrich pericardium may continue to be an alternative biological material for the construction of heart valve leaflets.
Measuring Disability: Comparing the Impact of Two Data Collection Approaches on Disability Rates
Sabariego, Carla; Oberhauser, Cornelia; Posarac, Aleksandra; Bickenbach, Jerome; Kostanjsek, Nenad; Chatterji, Somnath; Officer, Alana; Coenen, Michaela; Chhan, Lay; Cieza, Alarcos
2015-01-01
The usual approach in disability surveys is to screen persons with disability upfront and then ask questions about everyday problems. The objectives of this paper are to demonstrate the impact of screeners on disability rates, to challenge the usual exclusion of persons with mild and moderate disability from disability surveys and to demonstrate the advantage of using an a posteriori cut-off. Using data of a pilot study of the WHO Model Disability Survey (MDS) in Cambodia and the polytomous Rasch model, metric scales of disability were built. The conventional screener approach based on the short disability module of the Washington City Group and the a posteriori cut-off method described in the World Disability Report were compared regarding disability rates. The screener led to imprecise rates and classified persons with mild to moderate disability as non-disabled, although these respondents already experienced important problems in daily life. The a posteriori cut-off applied to the general population sample led to a more precise disability rate and allowed for a differentiation of the performance and needs of persons with mild, moderate and severe disability. This approach can be therefore considered as an inclusive approach suitable to monitor the Convention on the Rights of Persons with Disabilities. PMID:26308039
Chien, Chia-Chang; Huang, Shu-Fen; Lung, For-Wey
2009-01-27
The purpose of this study was to apply a two-stage screening method for the large-scale intelligence screening of military conscripts. We collected 99 conscripted soldiers whose educational levels were senior high school level or lower to be the participants. Every participant was required to take the Wisconsin Card Sorting Test (WCST) and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) assessments. Logistic regression analysis showed the conceptual level responses (CLR) index of the WCST was the most significant index for determining intellectual disability (ID; FIQ ≤ 84). We used the receiver operating characteristic curve to determine the optimum cut-off point of CLR. The optimum one cut-off point of CLR was 66; the two cut-off points were 49 and 66. Comparing the two-stage window screening with the two-stage positive screening, the area under the curve and the positive predictive value increased. Moreover, the cost of the two-stage window screening decreased by 59%. The two-stage window screening is more accurate and economical than the two-stage positive screening. Our results provide an example for the use of two-stage screening and the possibility of the WCST to replace WAIS-R in large-scale screenings for ID in the future.
The complex phase gradient method applied to leaky Lamb waves.
Lenoir, O; Conoir, J M; Izbicki, J L
2002-10-01
The classical phase gradient method applied to the characterization of the angular resonances of an immersed elastic plate, i.e., the angular poles of its reflection coefficient R, was proved to be efficient when their real parts are close to the real zeros of R and their imaginary parts are not too large compared to their real parts. This method consists of plotting the partial reflection coefficient phase derivative with respect to the sine of the incidence angle, considered as real, versus incidence angle. In the vicinity of a resonance, this curve exhibits a Breit-Wigner shape, whose minimum is located at the pole real part and whose amplitude is the inverse of its imaginary part. However, when the imaginary part is large, this method is not sufficiently accurate compared to the exact calculation of the complex angular root. An improvement of this method consists of plotting, in 3D, in the complex angle plane and at a given frequency, the angular phase derivative with respect to the real part of the sine of the incidence angle, considered as complex. When the angular pole is reached, the 3D curve shows a clear-cut transition whose position is easily obtained.
Sánchez, G; Elizaquível, P; Aznar, R
2012-01-03
Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, a rapid concentration method has been developed for the simultaneous recovery of hepatitis A virus (HAV), norovirus (NV), murine norovirus (MNV) as a surrogate for NV, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enterica. Initial experiments focused on evaluating the elution conditions suitable for virus release from vegetables. Finally, elution with buffered peptone water (BPW), using a Pulsifier, and concentration by polyethylene glycol (PEG) precipitation were the methods selected for the elution and concentration of both, enteric viruses and bacteria, from three different types of fresh-cut vegetables by quantitative PCR (qPCR) using specific primers. The average recoveries from inoculated parsley, spinach and salad, were ca. 9.2%, 43.5%, and 20.7% for NV, MNV, and HAV, respectively. Detection limits were 132 RT-PCR units (PCRU), 1.5 50% tissue culture infectious dose (TCID₅₀), and 6.6 TCID₅₀ for NV, MNV, and HAV, respectively. This protocol resulted in average recoveries of 57.4%, 64.5% and 64.6% in three vegetables for E. coli O157:H7, L. monocytogenes and Salmonella with corresponding detection limits of 10³, 10² and 10³ CFU/g, respectively. Based on these results, it can be concluded that the procedure herein is suitable to recover, detect and quantify enteric viruses and foodborne pathogenic bacteria within 5 h and can be applied for the simultaneous detection of both types of foodborne pathogens in fresh-cut vegetables. Copyright © 2011 Elsevier B.V. All rights reserved.
A dimensionally split Cartesian cut cell method for hyperbolic conservation laws
NASA Astrophysics Data System (ADS)
Gokhale, Nandan; Nikiforakis, Nikos; Klein, Rupert
2018-07-01
We present a dimensionally split method for solving hyperbolic conservation laws on Cartesian cut cell meshes. The approach combines local geometric and wave speed information to determine a novel stabilised cut cell flux, and we provide a full description of its three-dimensional implementation in the dimensionally split framework of Klein et al. [1]. The convergence and stability of the method are proved for the one-dimensional linear advection equation, while its multi-dimensional numerical performance is investigated through the computation of solutions to a number of test problems for the linear advection and Euler equations. When compared to the cut cell flux of Klein et al., it was found that the new flux alleviates the problem of oscillatory boundary solutions produced by the former at higher Courant numbers, and also enables the computation of more accurate solutions near stagnation points. Being dimensionally split, the method is simple to implement and extends readily to multiple dimensions.
Core Cutting Test with Vertical Rock Cutting Rig (VRCR)
NASA Astrophysics Data System (ADS)
Yasar, Serdar; Osman Yilmaz, Ali
2017-12-01
Roadheaders are frequently used machines in mining and tunnelling, and performance prediction of roadheaders is important for project economics and stability. Several methods were proposed so far for this purpose and, rock cutting tests are the best choice. Rock cutting tests are generally divided into two groups which are namely, full scale rock cutting tests and small scale rock cutting tests. These two tests have some superiorities and deficiencies over themselves. However, in many cases, where rock sampling becomes problematic, small scale rock cutting test (core cutting test) is preferred for performance prediction, since small block samples and core samples can be conducted to rock cutting testing. Common problem for rock cutting tests are that they can be found in very limited research centres. In this study, a new mobile rock cutting testing equipment, vertical rock cutting rig (VRCR) was introduced. Standard testing procedure was conducted on seven rock samples which were the part of a former study on cutting rocks with another small scale rock cutting test. Results showed that core cutting test can be realized successfully with VRCR with the validation of paired samples t-test.
Energy characteristics of the CO2 laser cutting of thick steel sheets
NASA Astrophysics Data System (ADS)
Orishich, A. M.
2012-01-01
In the present paper the scaling laws for the oxygen-assisted laser cutting of low-carbon steel of 5-25 mm is studied experimentally. No dross and minimal roughness of the cut surface were chosen as criteria of quality. The paper also studies the possibility to describe the cutting process by the similarity method and as ratios between dimensionless variables. Normalized power W/ktT, normalized velocity Vcb/a (Peclet number) and kerf width have special optimum numb. Formulas were obtained to determine the optimum values of the laser power and cutting speed for the given sheet thickness. The energy balance of the oxygen-assisted laser cutting is studied experimentally at these optimum parameters. The absorbed laser energy, heat conduction losses and cut width were measured experimentally, and then the energy of exothermic reaction of oxidation was found from the balance equation. To define the integral coefficient of absorption, the laser power was measured on the cutting channel exit during the cutting. The heat conduction losses were measured by the calorimetric method. It has been established that the absorbed laser energy, oxidation energy, thermal losses and melting enthalpy related to a sheet thickness unit, do not depend on the sheet thickness at the cutting with the minimal roughness. The results enable to determine the fraction of the oxidized iron in the melt and thermal efficiency at the cutting with the minimal roughness. The share of the oxidation reaction energy is 50-60% in the total contributed energy.
David L. Graney; Paul A. Murphy
1997-01-01
A test of group-selection and single-tree selection cutting methods was installed in 80-year-old even-aged oak-hickory stands in the Boston Mountains of northern Arkansas. Twenty-four 11-ac study plots were installed in well stocked stands representing north or east and south or west aspects. Stands between group openings were cut to residual basal areas of 65 and 85...
NASA Astrophysics Data System (ADS)
Li, Peng; Jiang, Shengyuan; Tang, Dewei; Xu, Bo
2017-05-01
For sake of striking a balance between the need of drilling efficiency and the constrains of power budget on the moon, the penetrations per revolution of drill bit are generally limited in the range around 0.1 mm, and besides the geometric angle of the cutting blade need to be well designed. This paper introduces a simulation approach based on PFC3D (particle flow code 3 dimensions) for analyzing the cutting load feature on lunar rock simulant, which is derived from different geometric-angle blades with a small cutting depth. The mean values of the cutting force of five blades in the survey region (four on the boundary points and one on the center point) are selected as the macroscopic responses of model. The method of experimental design which includes Plackett-Burman (PB) design and central composite design (CCD) method is adopted in the matching procedure of microparameters in PFC model. Using the optimization method of enumeration, the optimum set of microparameters is acquired. Then, the experimental validation is implemented by using other twenty-five blades with different geometric angles, and the results from both simulations and laboratory tests give fair agreements. Additionally, the rock breaking process cut by different blades are quantified from simulation analysis. This research provides the theoretical support for the refinement of the rock cutting load prediction and the geometric design of cutting blade on the drill bit.
Mita, Kazuhito; Ito, Hideto; Fukumoto, Masato; Murabayashi, Ryo; Koizumi, Kazuya; Hayashi, Takashi; Kikuchi, Hiroyuki; Kagaya, Tadashi
2011-01-01
Pancreatic fistula is the most common complication following distal pancreatectomy. We have developed a fibrin adhesive sealing method which covers the cut surface and parenchyma of the pancreas, to prevent pancreatic fistula. We performed 25 distal pancreatectomies. Fibrin adhesive (TachoComb) was applied to the staple line of the pancreas before stapling. Pancreatic fistula was defined and graded according to the International Study Group of Postoperative Pancreatic Fistula (ISGPF) definition. The overall incidence of pancreatic fistula was five cases (20%). Four cases (16%) were classified as Grade A. Only one case (4%) was classified as Grade B. In patients with or without pancreatic fistula, the mean length of postoperative hospital stay was not significant. The fibrin adhesive sealing method is a simple and effective method of preventing postoperative pancreatic fistula formation after distal pancreatectomy.
All-dielectric perforated metamaterials with toroidal dipolar response (Conference Presentation)
NASA Astrophysics Data System (ADS)
Stenishchev, Ivan; Basharin, Alexey A.
2017-05-01
We present metamaterials based on dielectric slab with perforated identical cylindrical clusters with perforated holes, which allow to support the toroidal dipolar response due to Mie-resonances in each hole. Note that proposed metamaterial is technologically simple for fabrication in optical frequency range. Metamaterial can be fabricated by several methods. For instance, we may apply the molecular beam epitaxy method for deposition of Si or GaAs layers, which have permittivity close to 16. Next step, nanometer/micrometer holes are perforated by focused ion beam method or laser cutting method. Fundamental difference of proposed metamaterial is technological fabrication process. Classically all- dielectric optical metamaterials consist of nano-spheres or nano-discs, which are complicated for fabrication, while our idea and suggested metamaterials are promising prototype of various optical/THz all-dielectic devices as sensor, nano-antennas elements for nanophotonics.
Mao, Fangjie; Zhou, Guomo; Li, Pingheng; Du, Huaqiang; Xu, Xiaojun; Shi, Yongjun; Mo, Lufeng; Zhou, Yufeng; Tu, Guoqing
2017-04-15
The selective cutting method currently used in Moso bamboo forests has resulted in a reduction of stand productivity and carbon sequestration capacity. Given the time and labor expense involved in addressing this problem manually, simulation using an ecosystem model is the most suitable approach. The BIOME-BGC model was improved to suit managed Moso bamboo forests, which was adapted to include age structure, specific ecological processes and management measures of Moso bamboo forest. A field selective cutting experiment was done in nine plots with three cutting intensities (high-intensity, moderate-intensity and low-intensity) during 2010-2013, and biomass of these plots was measured for model validation. Then four selective cutting scenarios were simulated by the improved BIOME-BGC model to optimize the selective cutting timings, intervals, retained ages and intensities. The improved model matched the observed aboveground carbon density and yield of different plots, with a range of relative error from 9.83% to 15.74%. The results of different selective cutting scenarios suggested that the optimal selective cutting measure should be cutting 30% culms of age 6, 80% culms of age 7, and all culms thereafter (above age 8) in winter every other year. The vegetation carbon density and harvested carbon density of this selective cutting method can increase by 74.63% and 21.5%, respectively, compared with the current selective cutting measure. The optimized selective cutting measure developed in this study can significantly promote carbon density, yield, and carbon sink capacity in Moso bamboo forests. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rock Drilling Performance Evaluation by an Energy Dissipation Based Rock Brittleness Index
NASA Astrophysics Data System (ADS)
Munoz, H.; Taheri, A.; Chanda, E. K.
2016-08-01
To reliably estimate drilling performance both tool-rock interaction laws along with a proper rock brittleness index are required to be implemented. In this study, the performance of a single polycrystalline diamond compact (PDC) cutter cutting and different drilling methods including PDC rotary drilling, roller-cone rotary drilling and percussive drilling were investigated. To investigate drilling performance by rock strength properties, laboratory PDC cutting tests were performed on different rocks to obtain cutting parameters. In addition, results of laboratory and field drilling on different rocks found elsewhere in literature were used. Laboratory and field cutting and drilling test results were coupled with values of a new rock brittleness index proposed herein and developed based on energy dissipation withdrawn from the complete stress-strain curve in uniaxial compression. To quantify cutting and drilling performance, the intrinsic specific energy in rotary-cutting action, i.e. the energy consumed in pure cutting action, and drilling penetration rate values in percussive action were used. The results show that the new energy-based brittleness index successfully describes the performance of different cutting and drilling methods and therefore is relevant to assess drilling performance for engineering applications.
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.
Survival Regression Modeling Strategies in CVD Prediction.
Barkhordari, Mahnaz; Padyab, Mojgan; Sardarinia, Mahsa; Hadaegh, Farzad; Azizi, Fereidoun; Bozorgmanesh, Mohammadreza
2016-04-01
A fundamental part of prevention is prediction. Potential predictors are the sine qua non of prediction models. However, whether incorporating novel predictors to prediction models could be directly translated to added predictive value remains an area of dispute. The difference between the predictive power of a predictive model with (enhanced model) and without (baseline model) a certain predictor is generally regarded as an indicator of the predictive value added by that predictor. Indices such as discrimination and calibration have long been used in this regard. Recently, the use of added predictive value has been suggested while comparing the predictive performances of the predictive models with and without novel biomarkers. User-friendly statistical software capable of implementing novel statistical procedures is conspicuously lacking. This shortcoming has restricted implementation of such novel model assessment methods. We aimed to construct Stata commands to help researchers obtain the aforementioned statistical indices. We have written Stata commands that are intended to help researchers obtain the following. 1, Nam-D'Agostino X 2 goodness of fit test; 2, Cut point-free and cut point-based net reclassification improvement index (NRI), relative absolute integrated discriminatory improvement index (IDI), and survival-based regression analyses. We applied the commands to real data on women participating in the Tehran lipid and glucose study (TLGS) to examine if information relating to a family history of premature cardiovascular disease (CVD), waist circumference, and fasting plasma glucose can improve predictive performance of Framingham's general CVD risk algorithm. The command is adpredsurv for survival models. Herein we have described the Stata package "adpredsurv" for calculation of the Nam-D'Agostino X 2 goodness of fit test as well as cut point-free and cut point-based NRI, relative and absolute IDI, and survival-based regression analyses. We hope this work encourages the use of novel methods in examining predictive capacity of the emerging plethora of novel biomarkers.
Moya, Nikolas; Falcão, Alexandre X; Ciesielski, Krzysztof C; Udupa, Jayaram K
2014-01-01
Graph-cut algorithms have been extensively investigated for interactive binary segmentation, when the simultaneous delineation of multiple objects can save considerable user's time. We present an algorithm (named DRIFT) for 3D multiple object segmentation based on seed voxels and Differential Image Foresting Transforms (DIFTs) with relaxation. DRIFT stands behind efficient implementations of some state-of-the-art methods. The user can add/remove markers (seed voxels) along a sequence of executions of the DRIFT algorithm to improve segmentation. Its first execution takes linear time with the image's size, while the subsequent executions for corrections take sublinear time in practice. At each execution, DRIFT first runs the DIFT algorithm, then it applies diffusion filtering to smooth boundaries between objects (and background) and, finally, it corrects possible objects' disconnection occurrences with respect to their seeds. We evaluate DRIFT in 3D CT-images of the thorax for segmenting the arterial system, esophagus, left pleural cavity, right pleural cavity, trachea and bronchi, and the venous system.
Human Sensibility Ergonomics Approach to Vehicle Simulator Based on Dynamics
NASA Astrophysics Data System (ADS)
Son, Kwon; Choi, Kyung-Hyun; Yoon, Ji-Sup
Simulators have been used to evaluate drivers' reactions to various transportation products. Most research, however, has concentrated on their technical performance. This paper considers driver's motion perception on a vehicle simulator through the analysis of human sensibility ergonomics. A sensibility ergonomic method is proposed in order to improve the reliability of vehicle simulators. A simulator in a passenger vehicle consists of three main modules such as vehicle dynamics, virtual environment, and motion representation modules. To evaluate drivers' feedback, human perceptions are categorized into a set verbal expressions collected and investigated to find the most appropriate ones for translation and angular accelerations of the simulator. The cut-off frequency of the washout filter in the representation module is selected as one sensibility factor. Sensibility experiments were carried out to find a correlation between the expressions and the cut-off frequency of the filter. This study suggests a methodology to obtain an ergonomic database that can be applied to the sensibility evaluation of dynamic simulators.
CFIRP: What we learned in the first ten years
Chambers, C.L.; McComb, W.C.; Tappeiner, J. C.; Kellogg, L.D.; Johnson, R.L.; Spycher, G.
1999-01-01
In response to public dissatisfaction with forest management methods, we initiated the College of Forestry Integrated Research Project (CFIRP) to test alternative silvicultural systems in Douglas-fir (Pseudotsuga menziesii stands in western Oregon. We compared costs and biological and human responses among a control and three replicated silvicultural alternatives to clearcutting that retained structural features found in old Douglas-fir forests. Treatments were applied within 8- to 15-ha stands and attempted to mimic crown fires (modified clearcut), windthrow (green tree retention), and small-scale impacts such as root rot diseases (small patch group selection). We also compared costs in three unreplicated treatments (large patch group selection, wedge cut, and strip cut). Each treatment included differences in the pattern of retained dead trees (snags), as either scattered individuals or as clumps. Good communication among researchers and managers, a long-term commitment to the project, and careful documentation of research sites and data are important to the success of long-term silvicultural research projects. To date, over 30 publications have resulted from the project.
Nondestructive and Real-time Measurement of Moisture in Plant
NASA Astrophysics Data System (ADS)
Ogawa, Yuichi; Kawase, Kodo; Mizuno, Maya; Yamashita, Masatsugu; Otani, Chiko
We constructed a THz transillumination system for water content monitoring, and we succeeded in measuring the moisture level in plants. Our measurement system uses a widely tunable coherent THz parametric oscillator source. As target we chose for this experiment a leaf of Japanese basil. The time variation of the water content in the leaf was monitored in two situations: a leaf freshly cut which is left to dry out, and the leaf of a water stressed plant. We found by real-time measurements that the water content of a cut leaf does not decrease uniformly in time. Also, the response to water stress is delayed by about 5-10 minutes. Furthermore, we demonstrated a moisture measurement using a transillumination THz imaging system. As target we chose for this experiment a leaf of Hedera helix held between two thin plastic sheets. The change of the moisture distribution is clearly visible. These results show that the method described here can be applied to nondestructive and real-time monitoring of water content in plants.
A new method for hepatic resection and hemostasis: absorbable plaque and suture.
Ozer, M Tahir; Eryilmaz, Mehmet; Coskun, Kagan; Demirbas, Sezai; Uzar, A Ihsan; Kozak, Orhan
2010-04-01
Blunt and penetrating hepatic injuries are conditions that are frequently encountered in emergency surgeries, and they involve high mortality morbidity. In the handling of such injuries, methods ranging from the application of simple cauterization and suturing for hemostasis to hepatic lobectomies, which might involve the removal of the greater part of the organ, have been defined. Due to the organ's fragility and susceptibility to bleeding, elective hepatic resections necessitate both surgical experience and technological equipment. Therefore, the demand still exists for an affordable and easy-to-use-method that could be applied by all centers. To meet this demand, we have developed a method of hemorrhage control via sutures supported by absorbable plaques that provide effective compression and prevent the suture from cutting the tissue during the application of the sutures in the treatment of such fragile organs as the liver. In our method, we have achieved hemostasis by bilaterally compressing the tissue through strong ties after placing, on the part of the tissue on which the sutures are applied, absorbable and flexible plaques that prevent the suture from cutting the tissue during the application of a polyglactin suture to the solid organ. To prevent dislocation of the plaques, we have fastened the sutures by reeving them through the holes made in the plaques. We have demonstrated the success and the practicality of our method by applying it on four pigs; we experimentally inflicted hepatic injuries on two pigs, and we performed resection on the other two pigs. The hepatic hemorrhages we developed in both of the animals were successfully restrained by the use of our method. On the other hand, two resections were performed on the right and left lobes of the other two animals. There were no hemorrhages during the surgery, and the procedure took 45 minutes in total. No postoperative complications occurred. While the liver function test values were high on the seventh day, due to the operation, they were observed to be normal on the thirtieth day. After the laparotomies, performed six months later, we observed that the plaques as well as the sutures were absorbed and that the injured tissues were completely healed. Additionally, it was observed during the pathological examination that the tissues beneath the area of application were healed through fibrosis and that the liver had no other pathologies. In conclusion, we believe that the method can be safely used in hepatic resections or traumatic hemorrhages in the proper locations.
NASA Astrophysics Data System (ADS)
Sun, Min; Chen, Xinjian; Zhang, Zhiqiang; Ma, Chiyuan
2017-02-01
Accurate volume measurements of pituitary adenoma are important to the diagnosis and treatment for this kind of sellar tumor. The pituitary adenomas have different pathological representations and various shapes. Particularly, in the case of infiltrating to surrounding soft tissues, they present similar intensities and indistinct boundary in T1-weighted (T1W) magnetic resonance (MR) images. Then the extraction of pituitary adenoma from MR images is still a challenging task. In this paper, we propose an interactive method to segment the pituitary adenoma from brain MR data, by combining graph cuts based active contour model (GCACM) and random walk algorithm. By using the GCACM method, the segmentation task is formulated as an energy minimization problem by a hybrid active contour model (ACM), and then the problem is solved by the graph cuts method. The region-based term in the hybrid ACM considers the local image intensities as described by Gaussian distributions with different means and variances, expressed as maximum a posteriori probability (MAP). Random walk is utilized as an initialization tool to provide initialized surface for GCACM. The proposed method is evaluated on the three-dimensional (3-D) T1W MR data of 23 patients and compared with the standard graph cuts method, the random walk method, the hybrid ACM method, a GCACM method which considers global mean intensity in region forces, and a competitive region-growing based GrowCut method planted in 3D Slicer. Based on the experimental results, the proposed method is superior to those methods.
36 CFR 223.195 - Procedures for identifying and marking unprocessed timber.
Code of Federal Regulations, 2013 CFR
2013-07-01
... pattern may not be used to mark logs from any other source for a period of 24 months after all logs have..., they shall be replaced. If the log is cut into two or more segments, each segment shall be identified... preserve identification of log pieces shall not apply to logs cut into two or more segments as a part of...
Assessing the Non-Timber Value of Forests: A Revealed-Preference, Hedonic Model
Riccardo Scarpa; Joseph Buongiorno; Jiin-Shyang Hseu; Karen Lee Abt
2000-01-01
Based on revealed preference theory, the value of non-timber goods and services obtained by forest owners, private or public, should be at least equal to the difference between the value of what they could have cut had they tried to maximize timber revenues, and of what they actually cut. This definition was applied to estimate the non-timber value (NTV) of...
Clyde G. Vidrine; John C. Adams
2002-01-01
Thirteen year growth results of 1-0 out-planted loblolly pine seedlings on nonintensively prepared up-land mixed pine-hardwood sites receiving machine applied cut-stump treatment (CST) herbicides onto hardwood stumps at the time of harvesting is presented. Plantation pine growth shows significantly higher growth for pine in the CST treated plots compared to non-CST...
Visible light exposure reduces the drip loss of fresh-cut watermelon.
Wang, Yubin; Li, Wu; Cai, Wenqian; Ma, Yue; Xu, Yong; Zhao, Xiaoyan; Zhang, Chao
2018-05-01
Drip loss of fresh-cut watermelon has become a concern for both producers and consumers. The effect of visible light exposure on the drip loss of fresh-cut watermelon was evaluated. Visible light treatments of 3000 and 10 Lux were applied to fresh-cut watermelon at 4 °C during the shelf life for 5 days, with light exposure of 150 Lux as the control. The drip loss of the fresh-cut watermelon at 3000 Lux was 74.8% of that at 150 Lux on the fifth day, and the moisture evaporation at 3000 Lux was 1.89 times that at 150 Lux. Moreover, the light exposure of 3000 Lux reduced the activity of polygalacturonase, which is a key hydrolase related to cell wall degradation. The cell wall degradation ratio of the fresh-cut watermelon at 3000 Lux was 81.7% of that at 150 Lux on the fifth day. Overall, light exposure of 3000 Lux reduced drip loss by accelerating moisture evaporation in fresh-cut watermelon, as well as by reducing the activity of polygalacturonase and the ratio of cell wall degradation. Hence, exposing the fresh-cut watermelon to visible light of 3000 Lux during the shelf life was a feasible way of reducing drip loss.
NASA Astrophysics Data System (ADS)
Nor Khairusshima, M. K.; Hafiz Zakwan, B. Muhammad; Suhaily, M.; Sharifah, I. S. S.; Shaffiar, N. M.; Rashid, M. A. N.
2018-01-01
Carbon Fibre Reinforced Plastic (CFRP) composite has become one of famous materials in industry, such as automotive, aeronautics, aerospace and aircraft. CFRP is attractive due to its properties, which promising better strength and high specification of mechanical properties other than its high resistance to corrosion. Other than being abrasive material due to the carbon nature, CFRP is an anisotropic material, which the knowledge of machining metal and steel cannot be applied during machining CFRP. The improper technique and parameters used to machine CFRP may result in high tool wear. This paper is to study the tool wear of 8 mm diameter carbide cutting tool during milling CFRP. To predict the suitable cutting parameters within range of 3500-6220 (rev/min), 200-245 (mm/min), and 0.4-1.8 (mm) for cutting speed, speed, feed rate and depth of cut respectively, which produce optimized result (less tool wear), Response Surface Methodology (RSM) has been used. Based on the developed mathematical model, feed rate was identified as the primary significant item that influenced tool wear. The optimized cutting parameters are cutting speed, feed and depth of cut of 3500 rev/min, 200 mm/min and 0.5 mm, respectively, with tool wear of 0.0267 mm. It is also can be observed that as the cutting speed and feed rate increased the tool wear is increasing.
Protecting Unrooted Cuttings From Bemisia tabaci (Hemiptera Aleyrodidae) During Propagation
Krauter, Peter C.; Arthurs, Steven
2017-01-01
Abstract In North America, the sweetpotato whitefly, Bemisia tabaci Genn., is an important pest of greenhouse poinsettia. Growers have limited options to control this pest during propagation of cuttings, which are rooted under mist for several weeks. Early establishment of this pest increases the difficulty of managing the whitefly and retaining high aesthetic standard during the remaining crop production phase. We evaluated two neonicotinoids with translaminar activity, thiamethoxam (Flagship 25WG), and acetamiprid (TriStar 70 WSP), for control of B. tabaci pre-infested on unrooted cuttings propagated under mist. In an experimental greenhouse, both materials significantly reduced whitefly populations, providing an average reduction of 87.8% and 61.5% total recovered whitefly stages respectively, compared with controls. In another test, dipping cuttings in thiamethoxam (immersion treatment) did not improve control significantly, when compared with foliar sprays applied at label rate. In a commercial greenhouse operation, immersion treatments of thiamethoxam on pre-infested poinsettia cuttings maintained whiteflies at ≤ 0.02/plant, compared with up to 0.33/plant in untreated cuttings. Our data suggest that treating unrooted cuttings before or at the start of propagation can be part of an overall strategy for growers to manage whiteflies in poinsettia production. PMID:28973486
The effect of workstation and task variables on forces applied during simulated meat cutting.
McGorry, Raymond W; Dempsey, Patrick G; O'Brien, Niall V
2004-12-01
The purpose of the study was to investigate factors related to force and postural exposure during a simulated meat cutting task. The hypothesis was that workstation, tool and task variables would affect the dependent kinetic variables of gripping force, cutting moment and the dependent kinematic variables of elbow elevation and wrist angular displacement in the flexion/extension and radial/ulnar deviation planes. To evaluate this hypothesis a 3 x 3 x 2 x 2 x 2 (surface orientation by surface height by blade angle by cut complexity by work pace) within-subject factorial design was conducted with 12 participants. The results indicated that the variables can act and interact to modify the kinematics and kinetics of a cutting task. Participants used greater grip force and cutting moment when working at a pace based on productivity. The interactions of the work surface height and orientation indicated that the use of an adjustable workstation could minimize wrist deviation from neutral and improve shoulder posture during cutting operations. Angling the knife blade also interacted with workstation variables to improve wrist and upper extremity posture, but this benefit must be weighed against the potential for small increases in force exposure.
Wear and breakage monitoring of cutting tools by an optical method: theory
NASA Astrophysics Data System (ADS)
Li, Jianfeng; Zhang, Yongqing; Chen, Fangrong; Tian, Zhiren; Wang, Yao
1996-10-01
An essential part of a machining system in the unmanned flexible manufacturing system, is the ability to automatically change out tools that are worn or damaged. An optoelectronic method for in situ monitoring of the flank wear and breakage of cutting tools is presented. A flank wear estimation system is implemented in a laboratory environment, and its performance is evaluated through turning experiments. The flank wear model parameters that need to be known a priori are determined through several preliminary experiments, or from data available in the literature. The resulting cutting conditions are typical of those used in finishing cutting operations. Through time and amplitude domain analysis of the cutting tool wear states and breakage states, it is found that the original signal digital specificity (sigma) 2x and the self correlation coefficient (rho) (m) can reflect the change regularity of the cutting tool wear and break are determined, but which is not enough due to the complexity of the wear and break procedure of cutting tools. Time series analysis and frequency spectrum analysis will be carried out, which will be described in the later papers.
Local Structure Fixation in the Composite Manufacturing Chain
NASA Astrophysics Data System (ADS)
Girdauskaite, Lina; Krzywinski, Sybille; Rödel, Hartmut; Wildasin-Werner, Andrea; Böhme, Ralf; Jansen, Irene
2010-12-01
Compared to metal materials, textile reinforced composites show interesting features, but also higher production costs because of low automation rate in the manufacturing chain at this time. Their applicability is also limited due to quality problems, which restrict the production of complex shaped dry textile preforms. New technologies, design concepts, and cost-effective manufacturing methods are needed in order to establish further fields of application. This paper deals with possible ways to improve the textile deformation process by locally applying a fixative to the structure parallel to the cut. This hinders unwanted deformation in the textile stock during the subsequent stacking and formation steps. It is found that suitable thermoplastic binders, applied in the appropriate manner do not restrict formation of the textile and have no negative influence on the mechanical properties of the composite.
Metallicity-Corrected Tip of the Red Giant Branch Distances to M66 and M96
NASA Astrophysics Data System (ADS)
Mager, Violet; Madore, Barry F.; Freedman, Wendy L.
2018-06-01
We present distances to M66 and M96 obtained through measurements of the tip of the red giant branch (TRGB) in HST ACS/WFC images, and give details of our method. The TRGB can be difficult to determine in color-magnitude diagrams where it is not a hard, well-defined edge. We discuss our approach to this in our edge-detection algorithm. Furthermore, metals affect the magnitude of the TRGB as a function of color, creating a slope to the edge that has been dealt with in the past by applying a red color cut-off. We instead apply a metallicity correction to the data that removes this effect, increasing the number of useable stars and providing a more accurate distance measurement.
Ali, S; Charles, T C; Glick, B R
2012-11-01
The ability of 1-aminocyclopropane-1-carboxylate (ACC) deaminase-containing plant growth-promoting bacterial (PGPB) endophytes Pseudomonas fluorescens YsS6 and Pseudomonas migulae 8R6, their ACC deaminase minus mutants and the rhizospheric plant growth-promoting bacterium Pseudomonas putida UW4 to delay the senescence of mini carnation cut flowers was assessed. Fresh cut flowers were incubated with either a bacterial cell suspension, the ethylene precursor ACC, the ethylene inhibitor l-α-(aminoethoxyvinyl)-glycine or 0·85% NaCl at room temperature for 11 days. Levels of flower senescence were recorded every other day. To verify the presence of endophytes inside the plant tissues, scanning electron microscopy was performed. Among all treatments, flowers treated with wild-type ACC deaminase-containing endophytic strains exhibited the most significant delay in flower senescence, while flowers treated with the ACC deaminase minus mutants senesced at a rate similar to the control. Flowers treated with Ps. putida UW4 senesced more rapidly than untreated control flowers. The only difference between wild-type and mutant bacterial endophytes was ACC deaminase activity so that it may be concluded that this enzyme is directly responsible for the significant delay in flower senescence. Despite containing ACC deaminase activity, Ps. putida UW4 is not taken up by the cut flowers and therefore has no effect on prolonging their shelf life. The world-wide cut flower industry currently uses expensive and potentially environmentally dangerous chemical inhibitors of ethylene to prolong the shelf life of cut flowers. The use of PGPB endophytes with ACC deaminase activity has the potential to replace the chemicals that are currently used by the cut flower industry. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
Brekke, Mette; Rekdal, Magne; Straand, Jørund
2007-06-01
To assess level of cardiovascular risk factors in a non-selected, middle-aged population. To estimate the proportion target for risk intervention according to present guidelines and according to different cut-off levels for two risk algorithms. Population survey, modelling study. The Norwegian Hordaland Health Study (HUSK) 1997-99. A total of 22 289 persons born in 1950-57. Own and relatives' cardiovascular morbidity, antihypertensive and lipid-lowering treatment, smoking, blood pressure, cholesterol. Framingham and Systematic Coronary Risk Evaluation (SCORE) algorithms. The European guidelines on CVD prevention in clinical practice were applied to estimate size of risk groups. Some 9.7% of men and 7.6% of women had CVD, diabetes mellitus, a high level of one specific risk factor, or received lipid-lowering or antihypertensive treatment. Applying a SCORE (60 years) cut-off level at 5% to the rest of the population selected 52.4% of men and 0.8% of women into a primary prevention group, while a cut-off level at 8% included 22.0% and 0.06% respectively. A cut-off level for the Framingham score (60 years) of 20% selected 43.6% of men and 4.7% of women, while a cut-off level of 25% selected 25.6% of men and 1.8% of women. The findings illustrate how choices regarding risk estimation highly affect the size of the target population. Modelling studies are important when preparing guidelines, to address implications for resource allocation and risk of medicalization. The population share to be targeted for primary prevention ought to be estimated, including the impact of various cut-off points for risk algorithms on the size of the risk population.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Towprayoon, S.; Kuntrangwattana, S.
Cutting oil wastewater from an iron and steel factory was applied to the soil windrow. Self-remediation was then compared with remediation with acclimatized indigenous microbes. The incremental reduction rate of the microorganisms and hydrocarbon-degradable microbes was slower in self-remediation than in the latter treatment. Within 30 days, when the acclimatized indigenous microbes were used, there was a significant reduction of the contaminated hydrocarbons, while self-remediation took longer to reduce to the same concentration. Various nitrogen sources were applied to the soil pile, namely, organic compost, chemical fertilizer, ammonium sulfate, and urea. The organic compost induced a high yield of hydrocarbon-degradablemore » microorganisms, but the rate at which the cutting oil in the soil decreased was slower than when other nitrogen sources were used. The results of cutting oil degradation studied by gas chromatography showed the absence of some important hydrocarbons. The increment of the hydrocarbon-degradable microbes in the land treatment ecosystem does not necessarily correspond to the hydrocarbon reduction efficiency. 3 refs., 3 figs.« less
NASA Astrophysics Data System (ADS)
Seon, Sangwoo; Shin, Jae Sung; Oh, Seong Yong; Park, Hyunmin; Chung, Chin-Man; Kim, Taek-Soo; Lee, Lim; Lee, Jonghwan
2018-07-01
A study was conducted to improve the cutting performance of a 60-mm thick stainless steel plate using a 6-kW fiber laser. Two techniques for improving the initial cutting performance were evaluated by preheating the work piece with a waiting time and step-like cutting speed increase. Both techniques showed improved cutting results compared to constant speed cutting. Among them, the method with a step-like cutting speed increase showed the better result in terms of cutting performance. As a result, a 60-mm thick stainless steel plate was cut at a maximum cutting speed of 72 mm/min with a preheating cutting speed of 24 mm/min. In order to confirm the effect of preheating, an additional experiment was performed to measure the temperature variation during the cutting process. Through this experiment, preheating temperature conditions were found to allow the specimen to be cut. It is expected that the results of this work will contribute to improving the cutting performance of thick metal structures in various industrial fields, as well as the dismantling of nuclear facilities using lasers in the future.
Fuzzy robust credibility-constrained programming for environmental management and planning.
Zhang, Yimei; Hang, Guohe
2010-06-01
In this study, a fuzzy robust credibility-constrained programming (FRCCP) is developed and applied to the planning for waste management systems. It incorporates the concepts of credibility-based chance-constrained programming and robust programming within an optimization framework. The developed method can reflect uncertainties presented as possibility-density by fuzzy-membership functions. Fuzzy credibility constraints are transformed to the crisp equivalents with different credibility levels, and ordinary fuzzy inclusion constraints are determined by their robust deterministic constraints by setting a-cut levels. The FRCCP method can provide different system costs under different credibility levels (lambda). From the results of sensitivity analyses, the operation cost of the landfill is a critical parameter. For the management, any factors that would induce cost fluctuation during landfilling operation would deserve serious observation and analysis. By FRCCP, useful solutions can be obtained to provide decision-making support for long-term planning of solid waste management systems. It could be further enhanced through incorporating methods of inexact analysis into its framework. It can also be applied to other environmental management problems.
Changing cultural attitudes towards female genital cutting.
Vogt, Sonja; Mohmmed Zaid, Nadia Ahmed; El Fadil Ahmed, Hilal; Fehr, Ernst; Efferson, Charles
2016-10-27
As globalization brings people with incompatible attitudes into contact, cultural conflicts inevitably arise. Little is known about how to mitigate conflict and about how the conflicts that occur can shape the cultural evolution of the groups involved. Female genital cutting is a prominent example. Governments and international agencies have promoted the abandonment of cutting for decades, but the practice remains widespread with associated health risks for millions of girls and women. In their efforts to end cutting, international agents have often adopted the view that cutting is locally pervasive and entrenched. This implies the need to introduce values and expectations from outside the local culture. Members of the target society may view such interventions as unwelcome intrusions, and campaigns promoting abandonment have sometimes led to backlash as they struggle to reconcile cultural tolerance with the conviction that cutting violates universal human rights. Cutting, however, is not necessarily locally pervasive and entrenched. We designed experiments on cultural change that exploited the existence of conflicting attitudes within cutting societies. We produced four entertaining movies that served as experimental treatments in two experiments in Sudan, and we developed an implicit association test to unobtrusively measure attitudes about cutting. The movies depart from the view that cutting is locally pervasive by dramatizing members of an extended family as they confront each other with divergent views about whether the family should continue cutting. The movies significantly improved attitudes towards girls who remain uncut, with one in particular having a relatively persistent effect. These results show that using entertainment to dramatize locally discordant views can provide a basis for applied cultural evolution without accentuating intercultural divisions.
Innovation Study for Laser Cutting of Complex Geometries with Paper Materials
NASA Astrophysics Data System (ADS)
Happonen, A.; Stepanov, A.; Piili, H.; Salminen, A.
Even though technology for laser cutting of paper materials has existed for over 30 years, it seems that results of applications of this technology and possibilities of laser cutting systems are not easily available. The aim of this study was to analyze the feasibility of the complex geometry laser cutting of paper materials and to analyze the innovation challenges and potential of current laser cutting technologies offer. This research studied the potential and possible challenges in applying CO2 laser cutting technology for cutting of paper materials in current supply chains trying to fulfil the changing needs of customer in respect of shape, fast response during rapid delivery cycle. The study is focused on examining and analyzing the different possibilities of laser cutting of paper material in application area of complex low volume geometry cutting. The goal of this case was to analyze the feasibility of the laser cutting from technical, quality and implementation points of view and to discuss availability of new business opportunities. It was noticed that there are new business models still available within laser technology applications in complex geometry cutting. Application of laser technology, in business-to-consume markets, in synergy with Internet service platforms can widen the customer base and offer new value streams for technology and service companies. Because of this, existing markets and competition has to be identified, and appropriate new and innovative business model needs to be developed. And to be competitive in the markets, models like these need to include the earning logic and the stages from production to delivery as discussed in the paper.
Counterbalance of cutting force for advanced milling operations
NASA Astrophysics Data System (ADS)
Tsai, Nan-Chyuan; Shih, Li-Wen; Lee, Rong-Mao
2010-05-01
The goal of this work is to concurrently counterbalance the dynamic cutting force and regulate the spindle position deviation under various milling conditions by integrating active magnetic bearing (AMB) technique, fuzzy logic algorithm and an adaptive self-tuning feedback loop. Since the dynamics of milling system is highly determined by a few operation conditions, such as speed of spindle, cut depth and feedrate, therefore the dynamic model for cutting process is more appropriate to be constructed by experiments, instead of using theoretical approach. The experimental data, either for idle or cutting, are utilized to establish the database of milling dynamics so that the system parameters can be on-line estimated by employing the proposed fuzzy logic algorithm as the cutting mission is engaged. Based on the estimated milling system model and preset operation conditions, i.e., spindle speed, cut depth and feedrate, the current cutting force can be numerically estimated. Once the current cutting force can be real-time estimated, the corresponding compensation force can be exerted by the equipped AMB to counterbalance the cutting force, in addition to the spindle position regulation by feedback of spindle position. On the other hand, for the magnetic force is nonlinear with respect to the applied electric current and air gap, the characteristics of the employed AMB is investigated also by experiments and a nonlinear mathematic model, in terms of air gap between spindle and electromagnetic pole and coil current, is developed. At the end, the experimental simulations on realistic milling are presented to verify the efficacy of the fuzzy controller for spindle position regulation and the capability of the dynamic cutting force counterbalance.
The Methodology of Calculation of Cutting Forces When Machining Composite Materials
NASA Astrophysics Data System (ADS)
Rychkov, D. A.; Yanyushkin, A. S.
2016-08-01
Cutting of composite materials has specific features and is different from the processing of metals. When this characteristic intense wear of the cutting tool. An important criterion in the selection process parameters composite processing is the value of the cutting forces, which depends on many factors and is determined experimentally, it is not always appropriate. The study developed a method of determining the cutting forces when machining composite materials and the comparative evaluation of the calculated and actual values of cutting forces. The methodology for calculating cutting forces into account specific features of the cutting tool and the extent of wear, the strength properties of the processed material and cutting conditions. Experimental studies conducted with fiberglass milling cutter equipped with elements of hard metal VK3M. The discrepancy between the estimated and the actual values of the cutting force is not more than 10%.
The Size of Gelatin Sponge Particles: Differences with Preparation Method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Katsumori, Tetsuya, E-mail: katsumo@eurus.dti.ne.jp; Kasahara, Toshiyuki
2006-12-15
Purpose. To assess whether the size distribution of gelatin sponge particles differed according to the method used to make them and the type of original sheet. Methods. Gelatin sponge particles of approximately 1-1.5 x 1-1.5 x 2 mm were made from either Spongel or Gelfoam sheets by cutting with a scalpel and scissors. Particles were also made of either Spongel or Gelfoam sheets by pumping with two syringes and a three-way stopcock. The size distribution of the particles in saline was compared among the groups. Results. (1) Cutting versus pumping: When Spongel was used, cutting produced lower rates of smallermore » particles {<=}500 {mu}m and larger particles >2000 {mu}m compared with pumping back and forth 30 times (1.1% vs 37.6%, p < 0.0001; 2.2% vs 14.4%, p = 0.008). When Gelfoam was used, cutting produced lower rates of smaller and larger particles compared with pumping (8.5% vs 20.4%, p = 0.1809; 0% vs 48.1%, p < 0.0001). (2) Spongel versus Gelfoam: There was no significant difference in the size distribution of the particles between Spongel and Gelfoam (p = 0.2002) when cutting was used. Conclusion. The size distribution of gelatin sponge particles differed according to the method used to make them. More uniform particle sizes can be achieved by cutting than by pumping.« less
Study of process parameter on mist lubrication of Titanium (Grade 5) alloy
NASA Astrophysics Data System (ADS)
Maity, Kalipada; Pradhan, Swastik
2017-02-01
This paper deals with the machinability of Ti-6Al-4V alloy with mist cooling lubrication using carbide inserts. The influence of process parameter on the cutting forces, evolution of tool wear, surface finish of the workpiece, material removal rate and chip reduction coefficient have been investigated. Weighted principal component analysis coupled with grey relational analysis optimization is applied to identify the optimum setting of the process parameter. Optimal condition of the process parameter was cutting speed at 160 m/min, feed at 0.16 mm/rev and depth of cut at 1.6 mm. Effects of cutting speed and depth of cut on the type of chips formation were observed. Most of the chips forms were long tubular and long helical type. Image analyses of the segmented chip were examined to study the shape and size of the saw tooth profile of serrated chips. It was found that by increasing cutting speed from 95 m/min to 160 m/min, the free surface lamella of the chips increased and the visibility of the saw tooth segment became clearer.
Mesoplasticity approach to studies of the cutting mechanism in ultra-precision machining
NASA Astrophysics Data System (ADS)
Lee, Rongbin W. B.; Wang, Hao; To, Suet; Cheung, Chi Fai; Chan, Chang Yuen
2014-03-01
There have been various theoretical attempts by researchers worldwide to link up different scales of plasticity studies from the nano-, micro- and macro-scale of observation, based on molecular dynamics, crystal plasticity and continuum mechanics. Very few attempts, however, have been reported in ultra-precision machining studies. A mesoplasticity approach advocated by Lee and Yang is adopted by the authors and is successfully applied to studies of the micro-cutting mechanisms in ultra-precision machining. Traditionally, the shear angle in metal cutting, as well as the cutting force variation, can only be determined from cutting tests. In the pioneering work of the authors, the use of mesoplasticity theory enables prediction of the fluctuation of the shear angle and micro-cutting force, shear band formation, chip morphology in diamond turning and size effect in nano-indentation. These findings are verified by experiments. The mesoplasticity formulation opens up a new direction of studies to enable how the plastic behaviour of materials and their constitutive representations in deformation processing, such as machining can be predicted, assessed and deduced from the basic properties of the materials measurable at the microscale.
Peters, O A; Morgental, R D; Schulze, K A; Paqué, F; Kopper, P M P; Vier-Pelisser, F V
2014-06-01
To develop a method to evaluate the cutting behaviour of nickel-titanium (NiTi) coronal flaring instruments. BioRaCe BR0 (BR), HyFlex CM 1 (HY), ProFile OS No. 2 (PF) and ProTaper Sx (PT) instruments were used in simulated coronal flaring using a lateral action against bovine dentine blocks, at 250 and 500 rpm. Cutting efficiency was assessed by three methods: first, areas of notches produced by instruments were directly measured under a stereomicroscope. Second, dentine specimens were then analysed by surface profilometry to determine the maximum cutting depth and finally by microcomputed tomography to assess the volume of removed dentine. Data were compared using parametric tests with the significance level set at 0.05. For all three methods, HY and PF were the most and the least cutting-efficient instruments, respectively (P < 0.05). Significant differences were detected between 250 and 500 rpm for HY and PT (area); for BR, HY and PT (depth); and for BR and HY (volume). There were strong positive correlations between the results obtained with those three different methods with r-values ranging from 0.81 to 0.92. Measuring the amount of material removed in a specific time under stereomicroscopy is a simple and rational way to assess the cutting behaviour of NiTi rotary instruments in lateral action. HyFlex, manufactured with thermomechanically treated NiTi wire, was the most efficient instrument, and increased rotational speed was associated with increased cutting efficiency. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions
Jingxin Wang; W. Dale Greene; Bryce J. Stokes
1998-01-01
We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...
Examining Classification Criteria: A Comparison of Three Cut Score Methods
ERIC Educational Resources Information Center
DiStefano, Christine; Morgan, Grant
2011-01-01
This study compared 3 different methods of creating cut scores for a screening instrument, T scores, receiver operating characteristic curve (ROC) analysis, and the Rasch rating scale method (RSM), for use with the Behavioral and Emotional Screening System (BESS) Teacher Rating Scale for Children and Adolescents (Kamphaus & Reynolds, 2007).…
Martínez-del Campo, Ana; Bodea, Smaranda; Hamer, Hilary A; Marks, Jonathan A; Haiser, Henry J; Turnbaugh, Peter J; Balskus, Emily P
2015-04-14
Elucidation of the molecular mechanisms underlying the human gut microbiota's effects on health and disease has been complicated by difficulties in linking metabolic functions associated with the gut community as a whole to individual microorganisms and activities. Anaerobic microbial choline metabolism, a disease-associated metabolic pathway, exemplifies this challenge, as the specific human gut microorganisms responsible for this transformation have not yet been clearly identified. In this study, we established the link between a bacterial gene cluster, the choline utilization (cut) cluster, and anaerobic choline metabolism in human gut isolates by combining transcriptional, biochemical, bioinformatic, and cultivation-based approaches. Quantitative reverse transcription-PCR analysis and in vitro biochemical characterization of two cut gene products linked the entire cluster to growth on choline and supported a model for this pathway. Analyses of sequenced bacterial genomes revealed that the cut cluster is present in many human gut bacteria, is predictive of choline utilization in sequenced isolates, and is widely but discontinuously distributed across multiple bacterial phyla. Given that bacterial phylogeny is a poor marker for choline utilization, we were prompted to develop a degenerate PCR-based method for detecting the key functional gene choline TMA-lyase (cutC) in genomic and metagenomic DNA. Using this tool, we found that new choline-metabolizing gut isolates universally possessed cutC. We also demonstrated that this gene is widespread in stool metagenomic data sets. Overall, this work represents a crucial step toward understanding anaerobic choline metabolism in the human gut microbiota and underscores the importance of examining this microbial community from a function-oriented perspective. Anaerobic choline utilization is a bacterial metabolic activity that occurs in the human gut and is linked to multiple diseases. While bacterial genes responsible for choline fermentation (the cut gene cluster) have been recently identified, there has been no characterization of these genes in human gut isolates and microbial communities. In this work, we use multiple approaches to demonstrate that the pathway encoded by the cut genes is present and functional in a diverse range of human gut bacteria and is also widespread in stool metagenomes. We also developed a PCR-based strategy to detect a key functional gene (cutC) involved in this pathway and applied it to characterize newly isolated choline-utilizing strains. Both our analyses of the cut gene cluster and this molecular tool will aid efforts to further understand the role of choline metabolism in the human gut microbiota and its link to disease. Copyright © 2015 Martínez-del Campo et al.
Setting Cut-Scores: A Critical Review of the Angoff and Modified Angoff Methods
ERIC Educational Resources Information Center
Ricker, Kathryn L.
2006-01-01
The purpose of this article is to review critically the Angoff (1971) and modified Angoff methods for setting cut-scores. The criteria used in this review were originally proposed by Berk (1986). The assumptions of the Angoff method and other current issues surrounding this method are also discussed. Recommendations are made for using the Angoff…
Automated segmentation of serous pigment epithelium detachment in SD-OCT images
NASA Astrophysics Data System (ADS)
Sun, Zhuli; Shi, Fei; Xiang, Dehui; Chen, Haoyu; Chen, Xinjian
2015-03-01
Pigment epithelium detachment (PED) is an important clinical manifestation of multiple chorio-retinal disease processes, which can cause the loss of central vision. A 3-D method is proposed to automatically segment serous PED in SD-OCT images. The proposed method consists of five steps: first, a curvature anisotropic diffusion filter is applied to remove speckle noise. Second, the graph search method is applied for abnormal retinal layer segmentation associated with retinal pigment epithelium (RPE) deformation. During this process, Bruch's membrane, which doesn't show in the SD-OCT images, is estimated with the convex hull algorithm. Third, the foreground and background seeds are automatically obtained from retinal layer segmentation result. Fourth, the serous PED is segmented based on the graph cut method. Finally, a post-processing step is applied to remove false positive regions based on mathematical morphology. The proposed method was tested on 20 SD-OCT volumes from 20 patients diagnosed with serous PED. The average true positive volume fraction (TPVF), false positive volume fraction (FPVF), dice similarity coefficient (DSC) and positive predictive value (PPV) are 97.19%, 0.03%, 96.34% and 95.59%, respectively. Linear regression analysis shows a strong correlation (r = 0.975) comparing the segmented PED volumes with the ground truth labeled by an ophthalmology expert. The proposed method can provide clinicians with accurate quantitative information, including shape, size and position of the PED regions, which can assist diagnose and treatment.
Control of red alder by cutting.
Dean S. DeBell; Thomas C. Turpin
1989-01-01
Effects of tree age, month of cut, and height and angle of cut on sprouting of red alder stumps were evaluated in a study designed to develop an effective method for controlling red alder in Douglas-fir plantations. Ninety-five percent or more of alder stumps cut in June or July died by the end of the next growing season; mortality was 88, 70, and 22 percent for stumps...
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.
Hou, Fang; Huang, Chang-Bing; Lesmes, Luis; Feng, Li-Xia; Tao, Liming; Zhou, Yi-Feng; Lu, Zhong-Lin
2010-01-01
Purpose. The qCSF method is a novel procedure for rapid measurement of spatial contrast sensitivity functions (CSFs). It combines Bayesian adaptive inference with a trial-to-trial information gain strategy, to directly estimate four parameters defining the observer's CSF. In the present study, the suitability of the qCSF method for clinical application was examined. Methods. The qCSF method was applied to rapidly assess spatial CSFs in 10 normal and 8 amblyopic participants. The qCSF was evaluated for accuracy, precision, test–retest reliability, suitability of CSF model assumptions, and accuracy of amblyopia screening. Results. qCSF estimates obtained with as few as 50 trials matched those obtained with 300 Ψ trials. The precision of qCSF estimates obtained with 120 and 130 trials, in normal subjects and amblyopes, matched the precision of 300 Ψ trials. For both groups and both methods, test–retest sensitivity estimates were well matched (all R > 0.94). The qCSF model assumptions were valid for 8 of 10 normal participants and all amblyopic participants. Measures of the area under log CSF (AULCSF) and the cutoff spatial frequency (cutSF) were lower in the amblyopia group; these differences were captured within 50 qCSF trials. Amblyopia was detected at an approximately 80% correct rate in 50 trials, when a logistic regression model was used with AULCSF and cutSF as predictors. Conclusions. The qCSF method is sufficiently rapid, accurate, and precise in measuring CSFs in normal and amblyopic persons. It has great potential for clinical practice. PMID:20484592
Device and method for producing a containment barrier underneath and around in-situ buried waste
Gardner, Bradley M.; Smith, Ann M.; Hanson, Richard W.; Hodges, Richard T.
1998-01-01
An apparatus for building a horizontal underground barrier by cutting through soil and depositing a slurry, preferably on which cures into a hardened material. The apparatus includes a digging means for cutting and removing soil to create a void under the surface of the ground and injection means for inserting barrier-forming material into the void. In one embodiment, the digging means is a continuous cutting chain. Mounted on the continuous cutting chain are cutter teeth for cutting through soil and discharge paddles for removing the loosened soil. This invention includes a barrier placement machine, a method for building an underground horizontal containment barrier using the barrier placement machine, and the underground containment system. Preferably the underground containment barrier goes underneath and around the site to be contained in a bathtub-type containment.
Effects of random aspects of cutting tool wear on surface roughness and tool life
NASA Astrophysics Data System (ADS)
Nabil, Ben Fredj; Mabrouk, Mohamed
2006-10-01
The effects of random aspects of cutting tool flank wear on surface roughness and on tool lifetime, when turning the AISI 1045 carbon steel, were studied in this investigation. It was found that standard deviations corresponding to tool flank wear and to the surface roughness increase exponentially with cutting time. Under cutting conditions that correspond to finishing operations, no significant differences were found between the calculated values of the capability index C p at the steady-state region of the tool flank wear, using the best-fit method or the Box-Cox transformation, or by making the assumption that the surface roughness data are normally distributed. Hence, a method to establish cutting tool lifetime could be established that simultaneously respects the desired average of surface roughness and the required capability index.
NASA Astrophysics Data System (ADS)
Abdelkrim, M.; Brabie, G.; Belloufi, A.; Catalin, T.; Chirita, B.
2017-08-01
Today major metal cutting companies in industrial countries, looking to gain time and reduce manufacturing costs while respecting the environment. There are many phenomena which affect the quality and production costs of the product, including cutting efforts, cutting temperature, residual stresses, etc. A better understanding of these phenomena will reduce production costs and maximize productivity. The aim of this work is to analyze the effect of machining conditions (cutting speed, feed speed and cutting depth) on cutting temperature and residual stresses, during the milling operations using the response surface method. A good accuracy between predicted and measured values of the cutting temperature was found, the cutting speed and the depth of cut are parameters whose effect is most sensitive to the residual stresses and the cutting temperature.However, little influence has been registered in the case of an increase of the feed rate. The percentage of error is 4.57%, indicating that the numerical approach can accurately predict the cutting temperature of the AISI 1045.
Subprimal purchasing and merchandising decisions for pork: relationship to retail value.
Lorenzen, C L; Walter, J P; Dockerty, T R; Griffin, D B; Johnson, H K; Savell, J W
1996-01-01
To assess retail value and profitability, cutting test data were obtained in a simulated retail cutting room for boxed pork subprimals, bone-in loins (n = 180), boneless loins (n = 94), Boston butts (n = 148), fresh hams (n = 28), and boneless hams (n = 23). Processing times (seconds) and retail weights (kilograms) were used to determine relative value. Cutting style affected (P < .05) value differential (US$/subprimal) for bone-in and boneless loins. When cutting styles within subprimals were pooled, value differential was affected (P < .05) by purchasing specification for bone-in loins, boneless loins, Boston butts, and inside fresh hams. Processing bone-in loins to a boneless end point produced a greater (P < .05) value differential and percentage of gross margin than a bone-in retail end point. Bone-in loins fabricated to a boneless retail end point produced a greater (P < .05) value differential and percentage of gross margin than boneless loins fabricated to the same end point. The increase in retail value can be attributed to the increased number and weight of retail cuts produced from bone-in loins. The thick, boneless loin cutting style produced a greater (P < .05) value differential and percentage of gross margin as a result of a lower (P < .05) cost of fabrication and increased value of retail cuts than the thin, boneless cutting style. In general, boneless pork cutting methods were more profitable than bone-in cutting methods regardless of subprimal.
Short-cut Methods versus Rigorous Methods for Performance-evaluation of Distillation Configurations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramapriya, Gautham Madenoor; Selvarajah, Ajiththaa; Jimenez Cucaita, Luis Eduardo
Here, this study demonstrates the efficacy of a short-cut method such as the Global Minimization Algorithm (GMA), that uses assumptions of ideal mixtures, constant molar overflow (CMO) and pinched columns, in pruning the search-space of distillation column configurations for zeotropic multicomponent separation, to provide a small subset of attractive configurations with low minimum heat duties. The short-cut method, due to its simplifying assumptions, is computationally efficient, yet reliable in identifying the small subset of useful configurations for further detailed process evaluation. This two-tier approach allows expedient search of the configuration space containing hundreds to thousands of candidate configurations for amore » given application.« less
Short-cut Methods versus Rigorous Methods for Performance-evaluation of Distillation Configurations
Ramapriya, Gautham Madenoor; Selvarajah, Ajiththaa; Jimenez Cucaita, Luis Eduardo; ...
2018-05-17
Here, this study demonstrates the efficacy of a short-cut method such as the Global Minimization Algorithm (GMA), that uses assumptions of ideal mixtures, constant molar overflow (CMO) and pinched columns, in pruning the search-space of distillation column configurations for zeotropic multicomponent separation, to provide a small subset of attractive configurations with low minimum heat duties. The short-cut method, due to its simplifying assumptions, is computationally efficient, yet reliable in identifying the small subset of useful configurations for further detailed process evaluation. This two-tier approach allows expedient search of the configuration space containing hundreds to thousands of candidate configurations for amore » given application.« less
Root Formation in Ethylene-Insensitive Plants1
Clark, David G.; Gubrium, Erika K.; Barrett, James E.; Nell, Terril A.; Klee, Harry J.
1999-01-01
Experiments with ethylene-insensitive tomato (Lycopersicon esculentum) and petunia (Petunia × hybrida) plants were conducted to determine if normal or adventitious root formation is affected by ethylene insensitivity. Ethylene-insensitive Never ripe (NR) tomato plants produced more belowground root mass but fewer aboveground adventitious roots than wild-type Pearson plants. Applied auxin (indole-3-butyric acid) increased adventitious root formation on vegetative stem cuttings of wild-type plants but had little or no effect on rooting of NR plants. Reduced adventitious root formation was also observed in ethylene-insensitive transgenic petunia plants. Applied 1-aminocyclopropane-1-carboxylic acid increased adventitious root formation on vegetative stem cuttings from NR and wild-type plants, but NR cuttings produced fewer adventitious roots than wild-type cuttings. These data suggest that the promotive effect of auxin on adventitious rooting is influenced by ethylene responsiveness. Seedling root growth of tomato in response to mechanical impedance was also influenced by ethylene sensitivity. Ninety-six percent of wild-type seedlings germinated and grown on sand for 7 d grew normal roots into the medium, whereas 47% of NR seedlings displayed elongated taproots, shortened hypocotyls, and did not penetrate the medium. These data indicate that ethylene has a critical role in various responses of roots to environmental stimuli. PMID:10482660
Point-Wise Phase Matching for Nonlinear Frequency Generation in Dielectric Resonators
NASA Technical Reports Server (NTRS)
Yu, Nan (Inventor); Strekalov, Dmitry V. (Inventor); Lin, Guoping (Inventor)
2016-01-01
An optical resonator fabricated from a uniaxial birefringent crystal, such as beta barium borate. The crystal is cut with the optical axis not perpendicular to a face of the cut crystal. In some cases the optical axis lies in the plane of the cut crystal face. An incident (input) electromagnetic signal (which can range from the infrared through the visible to the ultraviolet) is applied to the resonator. An output signal is recovered which has a frequency that is an integer multiple of the frequency of the input signal. In some cases a prism is used to evanescently couple the input and the output signals to the resonator.
Atmospheric Plasma Blade for Surgical Purposes
NASA Astrophysics Data System (ADS)
Oksuz, Lutfi; Yurdabak Karaca, Gozde; Özkaptan, Emir; Uygun, Emre; Uygun Oksuz, Aysegul
2017-10-01
Atmospheric plasma cut is a process at the minimum level due to the ions, radicals and free electrons generated by the active electrode and target tissue. Atmospheric plasma cutting devices provide significant advantages as a non-contact electrocautery system that can operate in isotonic environment. During operations where plasma cutting is applied, bleeding is controlled and the side effects that would create the isotonic environment are eliminated. In this study in vivo and in vitro studies will be carried out by producing and optimizing the atmospheric plasma blade. Once the optimum parameters of the instrument are determined, in vivo studies will be performed and the pathology results will be evaluated.
NASA Astrophysics Data System (ADS)
Phi Long, Nguyen; Matsunaga, Yukihiro; Hanari, Toshihide; Yamada, Tomonori; Muramatsu, Toshiharu
2016-10-01
Experiment of temperature measurement was performed to investigate the transient temperature characteristics of molten metal during laser cutting. The aim of this study was to establish a method for measuring the surface temperature variation near the molten pool correlated with changes in cutting parameters. The relationship between temperature inside the kerf cut and characteristic of the cut surface was investigated by using thermography and thermocouples. Results show strong correlations between the transient temperatures and the thermal image for different cutting conditions. In addition, two-color thermometer has been used to obtain radiation intensity emitted from the irradiating zone as a function of operating conditions. Experiments have shown that one can detect the cutting quality by characterization of the surface temperature during laser cutting process.
Pre-release plastic packaging of MEMS and IMEMS devices
Peterson, Kenneth A.; Conley, William R.
2002-01-01
A method is disclosed for pre-release plastic packaging of MEMS and IMEMS devices. The method can include encapsulating the MEMS device in a transfer molded plastic package. Next, a perforation can be made in the package to provide access to the MEMS elements. The non-ablative material removal process can include wet etching, dry etching, mechanical machining, water jet cutting, and ultrasonic machining, or any combination thereof. Finally, the MEMS elements can be released by using either a wet etching or dry plasma etching process. The MEMS elements can be protected with a parylene protective coating. After releasing the MEMS elements, an anti-stiction coating can be applied. The perforating step can be applied to both sides of the device or package. A cover lid can be attached to the face of the package after releasing any MEMS elements. The cover lid can include a window for providing optical access. The method can be applied to any plastic packaged microelectronic device that requires access to the environment, including chemical, pressure, or temperature-sensitive microsensors; CCD chips, photocells, laser diodes, VCSEL's, and UV-EPROMS. The present method places the high-risk packaging steps ahead of the release of the fragile portions of the device. It also provides protection for the die in shipment between the molding house and the house that will release the MEMS elements and subsequently treat the surfaces.
Automatic 3D kidney segmentation based on shape constrained GC-OAAM
NASA Astrophysics Data System (ADS)
Chen, Xinjian; Summers, Ronald M.; Yao, Jianhua
2011-03-01
The kidney can be classified into three main tissue types: renal cortex, renal medulla and renal pelvis (or collecting system). Dysfunction of different renal tissue types may cause different kidney diseases. Therefore, accurate and efficient segmentation of kidney into different tissue types plays a very important role in clinical research. In this paper, we propose an automatic 3D kidney segmentation method which segments the kidney into the three different tissue types: renal cortex, medulla and pelvis. The proposed method synergistically combines active appearance model (AAM), live wire (LW) and graph cut (GC) methods, GC-OAAM for short. Our method consists of two main steps. First, a pseudo 3D segmentation method is employed for kidney initialization in which the segmentation is performed slice-by-slice via a multi-object oriented active appearance model (OAAM) method. An improved iterative model refinement algorithm is proposed for the AAM optimization, which synergistically combines the AAM and LW method. Multi-object strategy is applied to help the object initialization. The 3D model constraints are applied to the initialization result. Second, the object shape information generated from the initialization step is integrated into the GC cost computation. A multi-label GC method is used to segment the kidney into cortex, medulla and pelvis. The proposed method was tested on 19 clinical arterial phase CT data sets. The preliminary results showed the feasibility and efficiency of the proposed method.
Dominus for cut flower production
USDA-ARS?s Scientific Manuscript database
Fumigation with methyl bromide was the principal method of soilborne pest control in cut flower production. Many cut flower growers in Florida have ceased production, but those that remain are restricted in the fumigants that they are able to utilize due to proximity to potable water sources and oc...
Modeling of thermal processes arising during shaping gears with internal non-involute teeth
NASA Astrophysics Data System (ADS)
Kanatnikov, N. V.; Kanatnikova, P. A.; Vlasov, V. V.; Pashmentova, A. S.
2018-03-01
The paper presents a model for predicting the thermal processes arising during shaping gears with internal non-involute teeth. The kinematics of cutting is modeled due to the analytical model. Chipping is modeled using the finite element method. The experiment is based on the method of infrared photography of the cutting process. The simulation results showed that the maximum temperatures and heat flows in the tool vary by more than 10% when the rake and clearance angels of the cutting are changed.
Numerical analyses of planer plasmonic focusing lens
NASA Astrophysics Data System (ADS)
Chou, Yen-Yu; Lee, Yeeu-Chang
2018-03-01
The use of polystyrene (PS) sphere lithography has been widely applied in the fabrication of micron and nano structures, due to their low cost and ease of fabrication in large scale applications. This study evaluated the feasibility of plasmonic lens base on metal thin films with nanohole structures fabricated by using PS sphere lithography through three-dimensional (3D) finite difference time domain (FDTD) method. We calculated the intensity profile of lens with various wavelength of incident light, lens size, cutting positions, diameters of nanohole, and periods of nanohole to investigate the geometric parameters influence on the focusing properties of the plasmonic lens.
Paulsamy, Sivachandran
2014-01-01
In wind energy systems employing permanent magnet generator, there is an imperative need to reduce the cogging torque for smooth and reliable cut in operation. In a permanent magnet generator, cogging torque is produced due to interaction of the rotor magnets with slots and teeth of the stator. This paper is a result of an ongoing research work that deals with various methods to reduce cogging torque in dual rotor radial flux permanent magnet generator (DRFPMG) for direct coupled stand alone wind energy systems (SAWES). Three methods were applied to reduce the cogging torque in DRFPMG. The methods were changing slot opening width, changing magnet pole arc width and shifting of slot openings. A combination of these three methods was applied to reduce the cogging torque to a level suitable for direct coupled SAWES. Both determination and reduction of cogging torque were carried out by finite element analysis (FEA) using MagNet Software. The cogging torque of DRFPMG has been reduced without major change in induced emf. A prototype of 1 kW, 120 rpm DRFPMG was fabricated and tested to validate the simulation results. The test results have good agreement with the simulation predictions. PMID:25202746
Paulsamy, Sivachandran
2014-01-01
In wind energy systems employing permanent magnet generator, there is an imperative need to reduce the cogging torque for smooth and reliable cut in operation. In a permanent magnet generator, cogging torque is produced due to interaction of the rotor magnets with slots and teeth of the stator. This paper is a result of an ongoing research work that deals with various methods to reduce cogging torque in dual rotor radial flux permanent magnet generator (DRFPMG) for direct coupled stand alone wind energy systems (SAWES). Three methods were applied to reduce the cogging torque in DRFPMG. The methods were changing slot opening width, changing magnet pole arc width and shifting of slot openings. A combination of these three methods was applied to reduce the cogging torque to a level suitable for direct coupled SAWES. Both determination and reduction of cogging torque were carried out by finite element analysis (FEA) using MagNet Software. The cogging torque of DRFPMG has been reduced without major change in induced emf. A prototype of 1 kW, 120 rpm DRFPMG was fabricated and tested to validate the simulation results. The test results have good agreement with the simulation predictions.
NASA Astrophysics Data System (ADS)
Raff, L. M.; Malshe, M.; Hagan, M.; Doughan, D. I.; Rockley, M. G.; Komanduri, R.
2005-02-01
A neural network/trajectory approach is presented for the development of accurate potential-energy hypersurfaces that can be utilized to conduct ab initio molecular dynamics (AIMD) and Monte Carlo studies of gas-phase chemical reactions, nanometric cutting, and nanotribology, and of a variety of mechanical properties of importance in potential microelectromechanical systems applications. The method is sufficiently robust that it can be applied to a wide range of polyatomic systems. The overall method integrates ab initio electronic structure calculations with importance sampling techniques that permit the critical regions of configuration space to be determined. The computed ab initio energies and gradients are then accurately interpolated using neural networks (NN) rather than arbitrary parametrized analytical functional forms, moving interpolation or least-squares methods. The sampling method involves a tight integration of molecular dynamics calculations with neural networks that employ early stopping and regularization procedures to improve network performance and test for convergence. The procedure can be initiated using an empirical potential surface or direct dynamics. The accuracy and interpolation power of the method has been tested for two cases, the global potential surface for vinyl bromide undergoing unimolecular decomposition via four different reaction channels and nanometric cutting of silicon. The results show that the sampling methods permit the important regions of configuration space to be easily and rapidly identified, that convergence of the NN fit to the ab initio electronic structure database can be easily monitored, and that the interpolation accuracy of the NN fits is excellent, even for systems involving five atoms or more. The method permits a substantial computational speed and accuracy advantage over existing methods, is robust, and relatively easy to implement.
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
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.
NASA Astrophysics Data System (ADS)
Ee, K. C.; Dillon, O. W.; Jawahir, I. S.
2004-06-01
This paper discusses the influence of major chip-groove parameters of a cutting tool on the chip formation process in orthogonal machining using finite element (FE) methods. In the FE formulation, a thermal elastic-viscoplastic material model is used together with a modified Johnson-Cook material law for the flow stress. The chip back-flow angle and the chip up-curl radius are calculated for a range of cutting conditions by varying the chip-groove parameters. The analysis provides greater understanding of the effectiveness of chip-groove configurations and points a way to correlate cutting conditions with tool-wear when machining with a grooved cutting tool.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ashbaugh, F.N.; Murry, K.R.
A method of boring two concentric holes of different depths is described utilizing an elongated boring tool having a tool axis of rotation, a longitudinally disposed tool centerline axis, and first and second transverse cutting edges at one end thereof extending across the boring tool, the second cutting edge being longitudinally rearwardly recessed with respect to the first cutting edge. The method consists of inserting the boring tool into an adjustable boring head, adjusting a distance B between the tool centerline axis and the tool axis of rotation such that the tool axis of rotation intersects a first boring areamore » of the first cutting edge; and boring the concentric holes having respectively larger and smaller diameters.« less
Generalized interactions using virtual tools within the spring framework: cutting
NASA Technical Reports Server (NTRS)
Montgomery, Kevin; Bruyns, Cynthia D.
2002-01-01
We present schemes for real-time generalized mesh cutting. Starting with the a basic example, we describe the details of implementing cutting on single and multiple surface objects as well as hybrid and volumetric meshes using virtual tools with single and multiple cutting surfaces. These methods have been implemented in a robust surgical simulation environment allowing us to model procedures ranging from animal dissection to cleft lip correction.
High power laser downhole cutting tools and systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O
Downhole cutting systems, devices and methods for utilizing 10 kW or more laser energy transmitted deep into the earth with the suppression of associated nonlinear phenomena. Systems and devices for the laser cutting operations within a borehole in the earth. These systems and devices can deliver high power laser energy down a deep borehole, while maintaining the high power to perform cutting operations in such boreholes deep within the earth.
Improved resolution by mounting of tissue sections for laser microdissection
van Dijk, M C R F; Rombout, P D M; Dijkman, H B P M; Ruiter, D J; Bernsen, M R
2003-01-01
Background: Laser microbeam microdissection has greatly facilitated the procurement of specific cell populations from tissue sections. However, the fact that a coverslip is not used means that the morphology of the tissue sections is often poor. Aims: To develop a mounting method that greatly improves the morphological quality of tissue sections for laser microbeam microdissection purposes so that the identification of target cells can be facilitated. Methods: Fresh frozen tissue and formalin fixed, paraffin wax embedded tissue specimens were used to test the morphological quality of mounted and unmounted tissue. The mounting solution consisted of an adhesive gum and blue ink diluted in water. Interference of the mounting solution with DNA quality was analysed by the polymerase chain reaction using 10–2000 cells isolated by microdissection from mounted and unmounted tissue. Results: The mounting solution greatly improved the morphology of tissue sections for laser microdissection purposes and had no detrimental effects on the isolation and efficiency of amplification of DNA. One disadvantage was that the mounting solution reduced the cutting efficiency of the ultraviolet laser. To minimise this effect, the mounting solution should be diluted as much as possible. Furthermore, the addition of blue ink to the mounting medium restores the cutting efficiency of the laser. Conclusions: The mounting solution is easy to prepare and apply and can be combined with various staining methods without compromising the quality of the DNA extracted. PMID:12890747
Litmus paper helps detect potential pancreatoenterostomy leakage.
Yamaguchi, K; Chijiwa, K; Shimizu, S; Yokohata, K; Tanaka, M
1998-03-01
Leakage of pancreatoenterostomy remains as a serious and fatal complication after pancreatectomy. Several risk factors have been reported, ie, normal pancreatic parenchyma, small pancreatic duct, a large amount of intraoperative blood loss, management of the cut surface of the pancreas, and the presence of preoperative jaundice. Transected pancreatic ductules on the cut surface of the pancreas that are not drained into the main pancreatic duct after pancreatectomy are one of the risks. The pancreatic juice is alkaline and turns red litmus to blue. In order to detect the transected pancreatic ductules on the cut surface of the pancreas, red litmus paper is applied to the cutting surface of the pancreas after stimulation of secretin. Nondrained, transected pancreatic ductules on the cut surface of the pancreas can be detected as blue spots on the red litmus paper. The corresponding areas to the blue spots can be transfixed with sutures to close the nondrained and transected pancreatic ductules. Litmus paper can be expected to detect pancreatoenterostomy leakage after pancreatectomy.
Resection with laser and high frequency cutting loop in tracheo-bronchial diseases.
Illum, P
1989-04-01
A total of 23 patients have been treated endoscopically during the last three and a half years for a variety of diseases in the tracheo-bronchial tree; nine had a tracheal stenosis. Thirteen patients have been treated by resection with a high frequency cutting loop, eleven with a CO2-laser and one with an argon laser. A total of 44 treatments have been performed. Half of the treatments were given because of various malignant diseases. The results of the treatment of this very mixed group of patients were, as a whole, satisfactory with both CO2-laser and cutting loop. A more precise technique can be applied with the CO2-laser than the cutting loop, though the latter is the more efficient and easy to work with. Care must be taken with the loop because of its greater cutting depth. The argon laser has only limited use in the treatment of diseases in the trachea.
26 CFR 1.585-7 - Elective cut-off method of changing from the reserve method of section 585.
Code of Federal Regulations, 2010 CFR
2010-04-01
... § 1.585-7 Elective cut-off method of changing from the reserve method of section 585. (a) General rule... section, and the bank must include in income any excess balance in this reserve, as required by paragraph...-disqualification loans—(1) In general. A bank that makes the election allowed by paragraph (a) of this section must...
Quality factors in beef, pork, and lamb cooked by microwaves.
Korschgen, B M; Baldwin, R E; Snider, S
1976-12-01
Three cooking treatments were applied to the longissimus muscle of beef and of pork and to deboned leg of lamb. Cooking treatments included: Intermittent energy application (3-min. cycle) with a microwave range operated at 220V and intermittent energy application (6-min. cycle) with a microwave range operated at 115V. Control roasts were cooked in a conventional gas oven (163+/-3 degrees C.). Cooking was adjusted so that roasts achieved an internal temperature of 70 degrees C. when cut for analyses. Cooking losses were significantly greater for microwave than for conventionally cooked beef. However, microwave cooking resulted in beef, pork, and lamb roasts with flavor of interior portions similar to those prepared conventionally. Flavor differences in samples from the edge of the slices of lamb and of pork and tenderness of lamb appeared to be related to cooking method. For these attributes, meat cooked conventionally was superior. In contrast, patterns in significant differences in tenderness and juiciness of beef and of pork were not consistent and were not related solely to method of cookery. Neither creatine nor creatinine was a good index of flavor of meat cooked by these methods. Aside from the time-saving aspect of microwave heating, there was no major advantage of one method of cooking over another. Thus, either high- or low- powered microwave equipment, operated at 2450 MHz, can be used satisfactorily for cooking tender cuts of beef, pork, and lamb.
McDonald, Scott D; Thompson, NiVonne L; Stratton, Kelcey J; Calhoun, Patrick S
2014-03-01
Self-report questionnaires are frequently used to identify PTSD among U.S. military personnel and Veterans. Two common scoring methods used to classify PTSD include: (1) a cut score threshold and (2) endorsement of PTSD symptoms meeting DSM-IV-TR symptom cluster criteria (SCM). A third method requiring a cut score in addition to SCM has been proposed, but has received little study. The current study examined the diagnostic accuracy of three scoring methods for the Davidson Trauma Scale (DTS) among 804 Afghanistan and Iraq war-era military Service Members and Veterans. Data were weighted to approximate the prevalence of PTSD and other Axis I disorders in VA primary care. As expected, adding a cut score criterion to SCM improved specificity and positive predictive power. However, a cut score of 68-72 provided optimal diagnostic accuracy. The utility of the DTS, the role of baseline prevalence, and recommendations for future research are discussed. Published by Elsevier Ltd.
On Computations of Duct Acoustics with Near Cut-Off Frequency
NASA Technical Reports Server (NTRS)
Dong, Thomas Z.; Povinelli, Louis A.
1997-01-01
The cut-off is a unique feature associated with duct acoustics due to the presence of duct walls. A study of this cut-off effect on the computations of duct acoustics is performed in the present work. The results show that the computation of duct acoustic modes near cut-off requires higher numerical resolutions than others to avoid being numerically cut off. Duct acoustic problems in Category 2 are solved by the DRP finite difference scheme with the selective artificial damping method and results are presented and compared to reference solutions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Jie; Ni, Ming-Jiu, E-mail: mjni@ucas.ac.cn
2014-01-01
The numerical simulation of Magnetohydrodynamics (MHD) flows with complex boundaries has been a topic of great interest in the development of a fusion reactor blanket for the difficulty to accurately simulate the Hartmann layers and side layers along arbitrary geometries. An adaptive version of a consistent and conservative scheme has been developed for simulating the MHD flows. Besides, the present study forms the first attempt to apply the cut-cell approach for irregular wall-bounded MHD flows, which is more flexible and conveniently implemented under adaptive mesh refinement (AMR) technique. It employs a Volume-of-Fluid (VOF) approach to represent the fluid–conducting wall interfacemore » that makes it possible to solve the fluid–solid coupling magnetic problems, emphasizing at how electric field solver is implemented when conductivity is discontinuous in cut-cell. For the irregular cut-cells, the conservative interpolation technique is applied to calculate the Lorentz force at cell-center. On the other hand, it will be shown how consistent and conservative scheme is implemented on fine/coarse mesh boundaries when using AMR technique. Then, the applied numerical schemes are validated by five test simulations and excellent agreement was obtained for all the cases considered, simultaneously showed good consistency and conservative properties.« less
Fifteen-year results from six cutting methods in second-growth northern hardwoods.
Gayne G. Erdmann; Robert R. Oberg
1973-01-01
Presents and compares stand growth and yield information from three single-tree selection cuts, a crop-tree release treatment, an 8-inch diameter limit cut, and an uncut control. Discusses the influence of stand density on basal area growth, cubic volume growth, and board-foot volume growth.
USDA-ARS?s Scientific Manuscript database
Nondestructive methods based on fluorescence hyperspectral imaging (HSI) techniques were developed in order to detect worms on fresh-cut lettuce. The optimal wavebands for detecting worms on fresh-cut lettuce were investigated using the one-way ANOVA analysis and correlation analysis. The worm detec...
NASA Astrophysics Data System (ADS)
Pan, Minqiang; Zeng, Dehuai; Tang, Yong
A novel multi-cutter milling process for multiple parallel microchannels with manifolds is proposed to address the challenge of mass manufacture as required for cost-effective commercial applications. Several slotting cutters are stacked together to form a composite tool for machining microchannels simultaneously. The feasibility of this new fabrication process is experimentally investigated under different machining conditions and reaction characteristics of methanol steam reforming for hydrogen production. The influences of cutting parameters and the composite tool on the microchannel qualities and burr formation are analyzed. Experimental results indicate that larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively good microchannel qualities and small burrs. Of all the cutting parameters considered in these experiments, 94.2 m min -1 cutting speed, 23.5 mm min -1 feed rate and 0.5 mm cutting depth are found to be the optimum value. According to the comparisons of experimental results of multi-cutter milling process and estimated one of other alternative methods, it is found that multi-cutter milling process shows much shorter machining time and higher work removal rate than that of other alternative methods. Reaction characteristics of methanol steam reforming in microchannels also indicate that multi-cutter milling process is probably suitable for a commercial application.
von See, Constantin; Stoetzer, Marcus; Ruecker, Martin; Wagner, Max; Schumann, Paul; Gellrich, Nils-Claudius
2014-01-01
The placement of self-tapping implants is associated with microfractures and the formation of bone chips along the cutting flutes. This study was conducted to investigate the effect of different cutting edge angles on chip formation during the machining of trabecular and cortical bone using instruments with a rough titanium surface. Mandibular cortical and trabecular bone specimens were obtained from freshly slaughtered domestic pigs. A predefined thrust force was applied to the specimens. Four specially designed cutting instruments that simulated dental implants and had a rough titanium surface were allowed to complete one full revolution at cutting edge angles of 55, 65, 75, and 85 degrees, respectively. Torque and thrust were measured during the cutting process. Bone chips were measured and weighed under a microscope. Different cutting edge angles did not lead to significant differences in torque. The lowest torque values were measured when the cutting edges were positioned at 65 degrees in trabecular bone and at 85 degrees in cortical bone. Bone chips were significantly larger and heavier at angles of 55 and 65 degrees than at angles of 75 and 85 degrees in trabecular bone. Instruments with a rough titanium surface show considerable angle-dependent differences in chip formation. In addition to bone density, the angle of the cutting edges should be taken into consideration during the placement of dental implants. Good results were obtained when the cutting edges were positioned at an angle of 65 degrees. This angle can have positive effects on osseointegration.
Reviews on laser cutting technology for industrial applications
NASA Astrophysics Data System (ADS)
Muangpool, T.; Pullteap, S.
2018-03-01
In this paper, an overview of the laser technology applied for the industrial has been reviewed. In general, this technology was used in several engineering applications such as industrial, medical, science, research sectors, etc. Focusing on the laser technology in the industrial section, it was, normally, employed for many purposes i.e. target marking, welding, drilling, and also cutting. Consequently, the laser cutting technology was, however, divided into three classifications YAG, CO2, and fiber laser, respectively. Each laser types have different advantages and disadvantages depending on the material type. The advantages by using laser cutting compared with the general cutting machines were exploited in terms of narrow kerf, high cutting speed, low heat-affected zone (HAZ), improve efficiency of the cutting process, high accuracy, etc. However, the main objectives from the technology used were increasing of the products and also decreasing the production cost. In the opposite way, some disadvantages of the technology were summarized by complexity to operate, high maintenance cost, and also high power consumption. In Thailand industry, there were many factories used this technology as a cutting process. Unfortunately, only few researches were published. It might explains that this technology were difficulty to develop, high investment, and also easy to import from aboard. For becoming to the Thailand 4.0 community, the Thailand industry might awareness to reduce the importing machine and boosting some policies to create novel innovative / know-how from the own country.
Mechanical specific energy versus depth of cut in rock cutting and drilling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Yaneng; Zhang, Wu; Gamwo, Isaac
The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of amore » cutter referred to as a wear flat, and that wear flat in the past is often considered to be fixed during cutting. But during a drilling operation by a full bit that consists of multiple circular cutters, the wear flat length may increase because of various wear mechanisms involved. The wear progression of cutters generally results in reduced efficiency with either increased MSE or decreased ROP. Also, an accurate estimate of removed rock volume is found important for the evaluation of MSE. The derived model is compared with experiment results from a single circular cutter, for cutting soft rock under ambient pressure with actual depth measured through a micrometer, and for cutting high strength rock under high pressure with actual cutting area measured by a confocal microscope. Lastly, the model is employed to interpret the evolution of MSE with depth of cut for a full drilling bit under confining pressure. The general form of equation of the developed model is found to describe well the experiment data and can be applied to interpret the drilling data for a full bit.« less
Mechanical specific energy versus depth of cut in rock cutting and drilling
Zhou, Yaneng; Zhang, Wu; Gamwo, Isaac; ...
2017-12-07
The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of amore » cutter referred to as a wear flat, and that wear flat in the past is often considered to be fixed during cutting. But during a drilling operation by a full bit that consists of multiple circular cutters, the wear flat length may increase because of various wear mechanisms involved. The wear progression of cutters generally results in reduced efficiency with either increased MSE or decreased ROP. Also, an accurate estimate of removed rock volume is found important for the evaluation of MSE. The derived model is compared with experiment results from a single circular cutter, for cutting soft rock under ambient pressure with actual depth measured through a micrometer, and for cutting high strength rock under high pressure with actual cutting area measured by a confocal microscope. Lastly, the model is employed to interpret the evolution of MSE with depth of cut for a full drilling bit under confining pressure. The general form of equation of the developed model is found to describe well the experiment data and can be applied to interpret the drilling data for a full bit.« less
Device and method for producing a containment barrier underneath and around in-situ buried waste
Gardner, B.M.; Smith, A.M.; Hanson, R.W.; Hodges, R.T.
1998-08-11
An apparatus is described for building a horizontal underground barrier by cutting through soil and depositing a slurry, preferably on which cures into a hardened material. The apparatus includes a digging means for cutting and removing soil to create a void under the surface of the ground and injection means for inserting barrier-forming material into the void. In one embodiment, the digging means is a continuous cutting chain. Mounted on the continuous cutting chain are cutter teeth for cutting through soil and discharge paddles for removing the loosened soil. This invention includes a barrier placement machine, a method for building an underground horizontal containment barrier using the barrier placement machine, and the underground containment system. Preferably the underground containment barrier goes underneath and around the site to be contained in a bathtub-type containment. 15 figs.
Quartz crystal resonator g sensitivity measurement methods and recent results
NASA Astrophysics Data System (ADS)
Driscoll, M. M.
1990-09-01
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 (5 x 10 to the -10th/g) than for the AT-cut units. However, smaller unit-to-unit gamma vector magnitude variation was exhibited by the AT-cut resonators.
NASA Astrophysics Data System (ADS)
Emam-Ismail, M.
2015-11-01
In a broad spectral range (300-2500 nm), we report the use of channeled spectra formed from the interference of polarized white light to extract the dispersion of the phase birefringence Δnp(λ) of the x- and y-cuts of lithium tantalite (LiTaO3:LT) plates. A new method named as wavenumber difference method is used to extract the spectral behavior of the phase birefringence of the x- and y- cuts of LT plates. The correctness of the obtained birefringence data is confirmed by using Jones vector method through recalculating the plates thicknesses. The spectral variation of the phase birefringence Δnp(λ) of the x- and y-cuts of LT plates is fitted to Cauchy dispersion function with relative error for both x- and y-cuts of order 2.4×10-4. The group birefringence dispersion Δng (λ) of the x- and y-cuts of LT plates is also calculated and fitted to Ghosh dispersion function with relative error for both x- and y-cuts of order 2.83×10-4. Furthermore, the phase retardation introduced by the x- and y-cuts of LT plates is also calculated. It is found that the amount of phase retardation confirms that the x- and y-cuts of LT plates can act as a multiple order half- and quarter-wave plates working at many different wavelengths through the spectral range 300-2500 nm. For the x- and y-cuts of LT plates, a large difference between group and phase birefringence is observed at a short wavelength (λ=300 nm); while such difference progressively diminished at longer wavelength (λ=2000 nm). In the near infrared region (NIR) region (700-2500 nm), a broad spectral full width at half maximum (FWHM) is observed for either x- or y-cut of LT plate which can act as if it is working as a zero order wave plate. Finally, an achromatic half-wave plate working at 598 nm and covering a wide spectral range (300-900 nm) is demonstrated experimentally by combining both x- and y-cuts of LT plates.
Brain Tumor Segmentation Using Deep Belief Networks and Pathological Knowledge.
Zhan, Tianming; Chen, Yi; Hong, Xunning; Lu, Zhenyu; Chen, Yunjie
2017-01-01
In this paper, we propose an automatic brain tumor segmentation method based on Deep Belief Networks (DBNs) and pathological knowledge. The proposed method is targeted against gliomas (both low and high grade) obtained in multi-sequence magnetic resonance images (MRIs). Firstly, a novel deep architecture is proposed to combine the multi-sequences intensities feature extraction with classification to get the classification probabilities of each voxel. Then, graph cut based optimization is executed on the classification probabilities to strengthen the spatial relationships of voxels. At last, pathological knowledge of gliomas is applied to remove some false positives. Our method was validated in the Brain Tumor Segmentation Challenge 2012 and 2013 databases (BRATS 2012, 2013). The performance of segmentation results demonstrates our proposal providing a competitive solution with stateof- the-art methods. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Room-temperature wafer bonding of LiNbO3 and SiO2 using a modified surface activated bonding method
NASA Astrophysics Data System (ADS)
Takigawa, Ryo; Higurashi, Eiji; Asano, Tanemasa
2018-06-01
In this paper, we report room-temperature bonding of LiNbO3 (LN) and SiO2/Si for the realization of a LN on insulator (LNOI)/Si hybrid wafer. We investigate the applicability of a modified surface activated bonding (SAB) method for the direct bonding of LN and a thermally grown SiO2 layer. The modified SAB method using ion beam bombardment demonstrates the room-temperature wafer bonding of LN and SiO2. The bonded wafer was successfully cut into 0.5 × 0.5 mm2 dies without interfacial debonding owing to the applied stress during dicing. In addition, the surface energy of the bonded wafer was estimated to be approximately 1.8 J/m2 using the crack opening method. These results indicate that a strong bond strength can be achieved, which may be sufficient for device applications.
Expanding the printable design space for lithography processes utilizing a cut mask
NASA Astrophysics Data System (ADS)
Wandell, Jerome; Salama, Mohamed; Wilkinson, William; Curtice, Mark; Feng, Jui-Hsuan; Gao, Shao Wen; Asthana, Abhishek
2016-03-01
The utilization of a cut-mask in semiconductor patterning processes has been in practice for logic devices since the inception of 32nm-node devices, notably with unidirectional gate level printing. However, the microprocessor applications where cut-mask patterning methods are used are expanding as Self-Aligned Double Patterning (SADP) processes become mainstream for 22/14nm fin diffusion, and sub-14nm metal levels. One common weakness for these types of lithography processes is that the initial pattern requiring the follow-up cut-mask typically uses an extreme off-axis imaging source such as dipole to enhance the resolution and line-width roughness (LWR) for critical dense patterns. This source condition suffers from poor process margin in the semi-dense (forbidden pitch) realm and wrong-way directional design spaces. Common pattern failures in these limited design regions include bridging and extra-printing defects that are difficult to resolve with traditional mask improvement means. This forces the device maker to limit the allowable geometries that a designer may use on a device layer. This paper will demonstrate methods to expand the usable design space on dipole-like processes such as unidirectional gate and SADP processes by utilizing the follow-up cut mask to improve the process window. Traditional mask enhancement means for improving the process window in this design realm will be compared to this new cut-mask approach. The unique advantages and disadvantages of the cut-mask solution will be discussed in contrast to those customary methods.
Meneses, Anderson Alvarenga de Moura; Palheta, Dayara Bastos; Pinheiro, Christiano Jorge Gomes; Barroso, Regina Cely Rodrigues
2018-03-01
X-ray Synchrotron Radiation Micro-Computed Tomography (SR-µCT) allows a better visualization in three dimensions with a higher spatial resolution, contributing for the discovery of aspects that could not be observable through conventional radiography. The automatic segmentation of SR-µCT scans is highly valuable due to its innumerous applications in geological sciences, especially for morphology, typology, and characterization of rocks. For a great number of µCT scan slices, a manual process of segmentation would be impractical, either for the time expended and for the accuracy of results. Aiming the automatic segmentation of SR-µCT geological sample images, we applied and compared Energy Minimization via Graph Cuts (GC) algorithms and Artificial Neural Networks (ANNs), as well as the well-known K-means and Fuzzy C-Means algorithms. The Dice Similarity Coefficient (DSC), Sensitivity and Precision were the metrics used for comparison. Kruskal-Wallis and Dunn's tests were applied and the best methods were the GC algorithms and ANNs (with Levenberg-Marquardt and Bayesian Regularization). For those algorithms, an approximate Dice Similarity Coefficient of 95% was achieved. Our results confirm the possibility of usage of those algorithms for segmentation and posterior quantification of porosity of an igneous rock sample SR-µCT scan. Copyright © 2017 Elsevier Ltd. All rights reserved.
10-kW-class YAG laser application for heavy components
NASA Astrophysics Data System (ADS)
Ishide, Takashi; Tsubota, S.; Nayama, Michisuke; Shimokusu, Yoshiaki; Nagashima, Tadashi; Okimura, K.
2000-02-01
The authors have put the YAG laser of the kW class to practical use for repair welding of nuclear power plant steam generator heat exchanger tubes, all-position welding of pipings, etc. This paper describes following developed methods and systems of high power YAG laser processing. First, we apply the 6 kW to 10 kW YAG lasers for welding and cutting in heavy components. The beam guide systems we have used are optical fibers which core diameter is 0.6 mm to 0.8 mm and its length is 200 m as standard one. Using these system, we can get the 1 pass penetration of 15 mm to 20 mm and multi pass welding for more thick plates. Cutting of 100 mm thickness plate data also described for dismantling of nuclear power plants. In these systems we carried out the in-process monitoring by using CCD camera image processing and monitoring fiber which placed coaxial to the YAG optical lens system. In- process monitoring by the monitoring fiber, we measured the light intensity from welding area. Further, we have developed new hybrid welding with the TIG electrode at the center of lens for high power. The hybrid welding with TIG-YAG system aims lightening of welding groove allowances and welding of high quality. Through these techniques we have applied 7 kW class YAG laser for welding in the components of nuclear power plants.
Arévalo, José Ramón; García-Domínguez, Celia; Naranjo-Cigala, Agustín; Grillo, Federico
2014-01-01
Prescribed fires are a powerful tool for reducing fire hazards by decreasing amounts of fuel. The main objective is to analyze the effects of prescribed burning on the understory vegetation composition as well as on the soil characteristics of a reforested stand of Pinus canariensis. The study attempts to identify the effects of the preburning treatment of cutting understory vegetation on the floristic parameters of the vegetation community. This study was carried out for two years following a prescribed fire in a Canarian pine stand. Cutting and burning treatment affected species composition and increased diversity. Burnt and cut plots were characterized by a diverse array of herbaceous species and by a lower abundance of Teline microphylla (endemic legume), although burning apparently induced its germination. Cut treatment was more consistently differentiated from the control plots than burnt treatment. Soil K decreased after both treatments, pH slightly decreased after cutting, while P and Ca increased after fire. From an ecological point of view, prescribed burning is a better management practice than cutting the woody species of the understory. However, long-term studies would be necessary to evaluate the effects of fire intensity, season and frequency in which the prescribed burning is applied. PMID:25147839
Arévalo, José Ramón; Fernández-Lugo, Silvia; García-Domínguez, Celia; Naranjo-Cigala, Agustín; Grillo, Federico; Calvo, Leonor
2014-01-01
Prescribed fires are a powerful tool for reducing fire hazards by decreasing amounts of fuel. The main objective is to analyze the effects of prescribed burning on the understory vegetation composition as well as on the soil characteristics of a reforested stand of Pinus canariensis. The study attempts to identify the effects of the preburning treatment of cutting understory vegetation on the floristic parameters of the vegetation community. This study was carried out for two years following a prescribed fire in a Canarian pine stand. Cutting and burning treatment affected species composition and increased diversity. Burnt and cut plots were characterized by a diverse array of herbaceous species and by a lower abundance of Teline microphylla (endemic legume), although burning apparently induced its germination. Cut treatment was more consistently differentiated from the control plots than burnt treatment. Soil K decreased after both treatments, pH slightly decreased after cutting, while P and Ca increased after fire. From an ecological point of view, prescribed burning is a better management practice than cutting the woody species of the understory. However, long-term studies would be necessary to evaluate the effects of fire intensity, season and frequency in which the prescribed burning is applied.
Venous tree separation in the liver: graph partitioning using a non-ising model.
O'Donnell, Thomas; Kaftan, Jens N; Schuh, Andreas; Tietjen, Christian; Soza, Grzegorz; Aach, Til
2011-01-01
Entangled tree-like vascular systems are commonly found in the body (e.g., in the peripheries and lungs). Separation of these systems in medical images may be formulated as a graph partitioning problem given an imperfect segmentation and specification of the tree roots. In this work, we show that the ubiquitous Ising-model approaches (e.g., Graph Cuts, Random Walker) are not appropriate for tackling this problem and propose a novel method based on recursive minimal paths for doing so. To motivate our method, we focus on the intertwined portal and hepatic venous systems in the liver. Separation of these systems is critical for liver intervention planning, in particular when resection is involved. We apply our method to 34 clinical datasets, each containing well over a hundred vessel branches, demonstrating its effectiveness.
Novel face-detection method under various environments
NASA Astrophysics Data System (ADS)
Jing, Min-Quan; Chen, Ling-Hwei
2009-06-01
We propose a method to detect a face with different poses under various environments. On the basis of skin color information, skin regions are first extracted from an input image. Next, the shoulder part is cut out by using shape information and the head part is then identified as a face candidate. For a face candidate, a set of geometric features is applied to determine if it is a profile face. If not, then a set of eyelike rectangles extracted from the face candidate and the lighting distribution are used to determine if the face candidate is a nonprofile face. Experimental results show that the proposed method is robust under a wide range of lighting conditions, different poses, and races. The detection rate for the HHI face database is 93.68%. For the Champion face database, the detection rate is 95.15%.
NASA Astrophysics Data System (ADS)
Toparli, M. Burak; Fitzpatrick, Michael E.; Gungor, Salih
2015-09-01
In this study, residual stress fields, including the near-surface residual stresses, were determined for an Al7050-T7451 sample after laser peening. The contour method was applied to measure one component of the residual stress, and the relaxed stresses on the cut surfaces were then measured by X-ray diffraction. This allowed calculation of the three orthogonal stress components using the superposition principle. The near-surface results were validated with results from incremental hole drilling and conventional X-ray diffraction. The results demonstrate that multiple residual stress components can be determined using a combination of the contour method and another technique. If the measured stress components are congruent with the principal stress axes in the sample, then this allows for determination of the complete stress tensor.
Lim, Se-Ho; Kim, Yeon-Ho; Kim, Moon-Key; Nam, Woong; Kang, Sang-Hoon
2016-12-01
We examined whether cutting a fibula graft with a surgical guide template, prepared with computer-aided design/computer-aided manufacturing (CAD/CAM), would improve the precision and accuracy of mandibular reconstruction. Thirty mandibular rapid prototype (RP) models were allocated to experimental (N = 15) and control (N = 15) groups. Thirty identical fibular RP models were assigned randomly, 15 to each group. For reference, we prepared a reconstructed mandibular RP model with a three-dimensional printer, based on surgical simulation. In the experimental group, a stereolithography (STL) surgical guide template, based on simulation, was used for cutting the fibula graft. In the control group, the fibula graft was cut manually, with reference to the reconstructed RP mandible model. The mandibular reconstructions were compared to the surgical simulation, and errors were calculated for both the STL surgical guide and the manual methods. The average differences in three-dimensional, minimum distances between the reconstruction and simulation were 9.87 ± 6.32 mm (mean ± SD) for the STL surgical guide method and 14.76 ± 10.34 mm (mean ± SD) for the manual method. The STL surgical guide method incurred less error than the manual method in mandibular reconstruction. A fibula cutting guide improved the precision of reconstructing the mandible with a fibula graft.
Inferior vena cava segmentation with parameter propagation and graph cut.
Yan, Zixu; Chen, Feng; Wu, Fa; Kong, Dexing
2017-09-01
The inferior vena cava (IVC) is one of the vital veins inside the human body. Accurate segmentation of the IVC from contrast-enhanced CT images is of great importance. This extraction not only helps the physician understand its quantitative features such as blood flow and volume, but also it is helpful during the hepatic preoperative planning. However, manual delineation of the IVC is time-consuming and poorly reproducible. In this paper, we propose a novel method to segment the IVC with minimal user interaction. The proposed method performs the segmentation block by block between user-specified beginning and end masks. At each stage, the proposed method builds the segmentation model based on information from image regional appearances, image boundaries, and a prior shape. The intensity range and the prior shape for this segmentation model are estimated based on the segmentation result from the last block, or from user- specified beginning mask if at first stage. Then, the proposed method minimizes the energy function and generates the segmentation result for current block using graph cut. Finally, a backward tracking step from the end of the IVC is performed if necessary. We have tested our method on 20 clinical datasets and compared our method to three other vessel extraction approaches. The evaluation was performed using three quantitative metrics: the Dice coefficient (Dice), the mean symmetric distance (MSD), and the Hausdorff distance (MaxD). The proposed method has achieved a Dice of [Formula: see text], an MSD of [Formula: see text] mm, and a MaxD of [Formula: see text] mm, respectively, in our experiments. The proposed approach can achieve a sound performance with a relatively low computational cost and a minimal user interaction. The proposed algorithm has high potential to be applied for the clinical applications in the future.
Numerical Modeling of the Work Piece Region in the Plasma Arc Cutting Process
NASA Astrophysics Data System (ADS)
Osterhouse, David
The plasma arc cutting process is widely used for the cutting of metals. The process, however, is not fully understood and further understanding will lead to further improvements. This work aims to elucidate the fundamental physical phenomena in the region where the plasma interacts with the work piece through the use of numerical modeling techniques. This model follows standard computational fluid dynamic methods that have been suitably modified to include plasma effects, assuming either local thermodynamic equilibrium or a slight non-equilibrium captured by the two-temperature assumption. This is implemented in the general purpose, open source CFD package, OpenFOAM. The model is applied to a plasma flow through a geometry that extends from inside the plasma torch to the bottom of the slot cut in the work piece. The shape of the kerf is taken from experimental measurements. The results of this model include the temperature, velocity, and electrical current distribution throughout the plasma. From this, the heat flux to and drag force on the work piece are calculated. The location of the arc attachment in the cut slot is also noted because it is a matter of interest in the published literature as well as significantly effecting the dynamics of the heat flux and drag force. The results of this model show that the LTE formulation is not sufficient to capture the physics present due to unphysical fluid dynamic instabilities and numerical problems with the arc attachment. The two-temperature formulation, however, captures a large part of the physics present. Of particular note, it is found that an additional inelastic collision factor is necessary to describe the increased energy transfer between electrons and diatomic molecules, which is widely neglected in published literature. It is also found that inclusion of the oxygen molecular ion is necessary to accurately describe the plasma flow, which has been neglected in all published two-temperature oxygen calculations. The heat flux is found to be greatest at the top of the cut slot where the thermal boundary layer is thinnest and the arc attachment increases heat transfer.
26 CFR 1.669(c)-1A - Special rules applicable to section 669.
Code of Federal Regulations, 2010 CFR
2010-04-01
... the 1980 Trust Y capital gain distribution. To compute A's tax under the exact method for 1974 on the... year taxpayer. Determination of the tax on the distribution under the short-cut method requires the use... income for 1975, for purposes of using the short-cut method to determine the tax from the trust T capital...
Chang, Shu Fang; Yang, Rong Sen
2014-09-01
To examine the cut-off point of the osteoporosis self-assessment tool, age, weight and body mass index for osteoporosis among young adult Taiwanese women, using a large-scale health examination database containing bone mineral density tests. The cut-off points of osteoporosis risk factors identified earlier focus on menopausal or senior Caucasian and Asian women. However, young adult Asian women have seldom been identified. A retrospective historical cohort study. Using the 2009-2011 health examination database of a large-scale medical centre in northern Taiwan, this study investigated young adult Asian women (i.e. range in age from 30-49 years) in Taiwan who had received dual-energy X-ray absorptiometry test. This study also explored the cut-off point, sensitivity, specificity and diagnostic accuracy of receiver operating characteristics of osteoporosis among young adult females in Taiwan. This study collected 2454 young adult Asian women in Taiwan. Cochran-Armitage analysis results indicated that the prevalence of osteoporosis increased with decreasing weight, body mass index and osteoporosis self-assessment method quartiles. According to the results of receiver operating characteristics, weight, body mass index and osteoporosis self-assessment tool approaches can generally be used as indicators to predict osteoporosis among young adult Asian women. Results of this study demonstrate that Taiwanese women contracting osteoporosis tend to be young and underweight, as well as having a low body mass index and osteoporosis self-assessment scores. Those results further suggest that the assessment indicators for cut-off points are appropriately suitable for young adult women in Taiwan. Early detection is the only available means of preventing osteoporosis. Professional nurses should apply convenient and accurate assessment procedures to help young adult women to adopt preventive strategies against osteoporosis early, thus eliminating the probability of osteoporotic fracture. © 2013 John Wiley & Sons Ltd.
Covic, Tanya; Pallant, Julie F; Conaghan, Philip G; Tennant, Alan
2007-01-01
Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D) scale using Rasch analysis in a rheumatoid arthritis (RA) population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF) and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression. PMID:17629902
A review of cutting mechanics and modeling techniques for biological materials.
Takabi, Behrouz; Tai, Bruce L
2017-07-01
This paper presents a comprehensive survey on the modeling of tissue cutting, including both soft tissue and bone cutting processes. In order to achieve higher accuracy in tissue cutting, as a critical process in surgical operations, the meticulous modeling of such processes is important in particular for surgical tool development and analysis. This review paper is focused on the mechanical concepts and modeling techniques utilized to simulate tissue cutting such as cutting forces and chip morphology. These models are presented in two major categories, namely soft tissue cutting and bone cutting. Fracture toughness is commonly used to describe tissue cutting while Johnson-Cook material model is often adopted for bone cutting in conjunction with finite element analysis (FEA). In each section, the most recent mathematical and computational models are summarized. The differences and similarities among these models, challenges, novel techniques, and recommendations for future work are discussed along with each section. This review is aimed to provide a broad and in-depth vision of the methods suitable for tissue and bone cutting simulations. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.
19 CFR 134.43 - Methods of marking specific articles.
Code of Federal Regulations, 2014 CFR
2014-04-01
... origin by cutting, die-sinking, engraving, stamping, or some other permanent method. The indelible... metal or plastic tag indelibly marked with the country of origin and permanently attached to the article... crafts must be indelibly marked with the country of origin by means of cutting, die-sinking, engraving...