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.
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.
The use of atlas registration and graph cuts for prostate segmentation in magnetic resonance images
DOE Office of Scientific and Technical Information (OSTI.GOV)
Korsager, Anne Sofie, E-mail: asko@hst.aau.dk; Østergaard, Lasse Riis; Fortunati, Valerio
2015-04-15
Purpose: An automatic method for 3D prostate segmentation in magnetic resonance (MR) images is presented for planning image-guided radiotherapy treatment of prostate cancer. Methods: A spatial prior based on intersubject atlas registration is combined with organ-specific intensity information in a graph cut segmentation framework. The segmentation is tested on 67 axial T{sub 2}-weighted MR images in a leave-one-out cross validation experiment and compared with both manual reference segmentations and with multiatlas-based segmentations using majority voting atlas fusion. The impact of atlas selection is investigated in both the traditional atlas-based segmentation and the new graph cut method that combines atlas andmore » intensity information in order to improve the segmentation accuracy. Best results were achieved using the method that combines intensity information, shape information, and atlas selection in the graph cut framework. Results: A mean Dice similarity coefficient (DSC) of 0.88 and a mean surface distance (MSD) of 1.45 mm with respect to the manual delineation were achieved. Conclusions: This approaches the interobserver DSC of 0.90 and interobserver MSD 0f 1.15 mm and is comparable to other studies performing prostate segmentation in MR.« less
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.
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.
Cutting tool form compensation system and method
Barkman, W.E.; Babelay, E.F. Jr.; Klages, E.J.
1993-10-19
A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed. 9 figures.
Cutting tool form compensaton system and method
Barkman, William E.; Babelay, Jr., Edwin F.; Klages, Edward J.
1993-01-01
A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed.
Regeneration after cutting of old-growth northern hardwoods in New Hampshire
William B. Leak; Robert W., Jr. Wilson
1958-01-01
Past experience with cuttings in old-growth northern hardwoods has demonstrated that the primary regeneration problem is to obtain a large proportion of desirable species of good quality. Regardless of method or intensity of cutting, the total amount of reproduction usually is adequate. Second-growth stands are a different story: this report pertains only to old-growth...
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
Ramos-Villarroel, Ana Y; Martín-Belloso, Olga; Soliva-Fortuny, Robert
2011-01-01
The effect of antibrowning compounds on the color and firmness of fresh-cut avocado treated with intense light pulses (ILP), as well as their impact on the survival of Listeria innocua, was investigated in this study. Dipping solutions containing 2% (w/v) L-cysteine without ascorbic acid and combined with 1% (w/v) citric acid and 1% w/v calcium lactate most effectively preserved the initial color and texture of ILP-treated fresh-cut avocado. On the other hand, ILP treatments caused a reduction of more than 3 log cycles in the populations of L. innocua inoculated on fresh-cut avocado. Log reduction levels increased when antibrowning agents were combined with ILP treatments. In conclusion, the use of quality-stabilizing agents is a good option to guarantee both the microbiological safety of fresh-cut avocado treated with ILP as well as to improve its physical and chemical quality. Intense light pulses (ILP) have received considerable attention during the last years after its approval by the U.S. Food and Drug Administration (FDA) in 1996 as a decontamination method for food or food surfaces. This article presents relevant information regarding the effect of ILP treatments combined with quality-stabilizing compounds as a feasible alternative to improve the physical and chemical quality of fresh-cut avocado as well as to guarantee its microbiological safety. © 2011 Institute of Food Technologists®
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.
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%.
Time-resolved light emission of a, c, and r-cut sapphires shock-compressed to 65 GPa
NASA Astrophysics Data System (ADS)
Liu, Q. C.; Zhou, X. M.
2018-04-01
To investigate light emission and dynamic deformation behaviors, sapphire (single crystal Al2O3) samples with three crystallographic orientations (a, c, and r-cut) were shock-compressed by the planar impact method, with final stress ranges from 47 to 65 GPa. Emission radiance and velocity versus time profiles were simultaneously measured with a fast pyrometer and a Doppler pin system in each experiment. Wave profile results show anisotropic elastic-plastic transitions, which confirm the literature observations. Under final shock stress of about 52 GPa, lower emission intensity is observed in the r-cut sample, in agreement with the previous report in the literature. When final shock stress increases to 57 GPa and 65 GPa, spectral radiance histories of the r-cut show two stages of distinct features. In the first stage, the emission intensity of r-cut is lower than those of the other two, which agrees with the previous report in the literature. In the second stage, spectral radiance of r-cut increases with time at much higher rate and it finally peaks over those of the a and c-cut. These observations (conversion of intensified emission in the r-cut) may indicate activation of a second slip system and formation of shear bands which are discussed with the resolved shear stress calculations for the slip systems in each of the three cuts under shock compression.
Hur, M. S.; Ersfeld, B.; Noble, A.; Suk, H.; Jaroszynski, D. A.
2017-01-01
Ultra-intense, narrow-bandwidth, electromagnetic pulses have become important tools for exploring the characteristics of matter. Modern tuneable high-power light sources, such as free-electron lasers and vacuum tubes, rely on bunching of relativistic or near-relativistic electrons in vacuum. Here we present a fundamentally different method for producing narrow-bandwidth radiation from a broad spectral bandwidth current source, which takes advantage of the inflated radiation impedance close to cut-off in a medium with a plasma-like permittivity. We find that by embedding a current source in this cut-off region, more than an order of magnitude enhancement of the radiation intensity is obtained compared with emission directly into free space. The method suggests a simple and general way to flexibly use broadband current sources to produce broad or narrow bandwidth pulses. As an example, we demonstrate, using particle-in-cell simulations, enhanced monochromatic emission of terahertz radiation using a two-colour pumped current source enclosed by a tapered waveguide. PMID:28071681
NASA Astrophysics Data System (ADS)
Hur, M. S.; Ersfeld, B.; Noble, A.; Suk, H.; Jaroszynski, D. A.
2017-01-01
Ultra-intense, narrow-bandwidth, electromagnetic pulses have become important tools for exploring the characteristics of matter. Modern tuneable high-power light sources, such as free-electron lasers and vacuum tubes, rely on bunching of relativistic or near-relativistic electrons in vacuum. Here we present a fundamentally different method for producing narrow-bandwidth radiation from a broad spectral bandwidth current source, which takes advantage of the inflated radiation impedance close to cut-off in a medium with a plasma-like permittivity. We find that by embedding a current source in this cut-off region, more than an order of magnitude enhancement of the radiation intensity is obtained compared with emission directly into free space. The method suggests a simple and general way to flexibly use broadband current sources to produce broad or narrow bandwidth pulses. As an example, we demonstrate, using particle-in-cell simulations, enhanced monochromatic emission of terahertz radiation using a two-colour pumped current source enclosed by a tapered waveguide.
Acoustics flow analysis in circular duct using sound intensity and dynamic mode decomposition
NASA Astrophysics Data System (ADS)
Weyna, S.
2014-08-01
Sound intensity generation in hard-walled duct with acoustic flow (no mean-flow) is treated experimentally and shown graphically. In paper, numerous methods of visualization illustrating the vortex flow (2D, 3D) can graphically explain diffraction and scattering phenomena occurring inside the duct and around open end area. Sound intensity investigation in annular duct gives a physical picture of sound waves in any duct mode. In the paper, modal energy analysis are discussed with particular reference to acoustics acoustic orthogonal decomposition (AOD). The image of sound intensity fields before and above "cut-off" frequency region are found to compare acoustic modes which might resonate in duct. The experimental results show also the effects of axial and swirling flow. However acoustic field is extremely complicated, because pressures in non-propagating (cut-off) modes cooperate with the particle velocities in propagating modes, and vice versa. Measurement in cylindrical duct demonstrates also the cut-off phenomenon and the effect of reflection from open end. The aim of experimental study was to obtain information on low Mach number flows in ducts in order to improve physical understanding and validate theoretical CFD and CAA models that still may be improved.
Zhang, Xin; Gu, Hui Yan; Chen, Xiang Wei
2018-02-01
In order to clarify the effects of selective cutting on soil phosphorus availability in Korean pine broad-leaved forest, surface soil (0-10 cm) samples from original Korean pine broad-leaved forest and natural forests with mild, medium and intensive cutting disturbances were collected. The Sui modified Hedley phosphorus fractionation method was used to continuously extract soil samples and analyzed the differences and changes of soil phosphorus fractions from different experimental stands. The results showed that the soil total phosphorus content of Korean pine broad-leaved forest varied from 1.09 to 1.66 g·kg -1 , with the original stand and intensive cutting disturbance stand being the maximum and minimum one, respectively. The differences of soil total phosphorus content among cutting disturbance levels were significant. The Olsen phosphorus and phosphorus activation coefficients changed with an amplitude of 7.26-17.79 mg·kg -1 and 0.67%-1.07%, respectively. Both of them significantly decreased with the increase of selective cutting disturbance level. The concentrations of all P fractions except HCl-P o , i.e., H 2 O-P i , NaHCO 3 -P, NaOH-P, HCl-P i , Residual-P, decreased with increasing cutting disturbance levels compared with original forest. The correlation coefficient between H 2 O-P i and soil Olsen phosphorus was the highest (0.98), though it only accounted for 1.5%-2.2% of the total phosphorus. NaOH-P content contributed to more than 48.0% of the total phosphorus, acknowledged as the potential source of soil phosphorus. In conclusion, selective cutting disturbance could constrain phosphorus storage and soil phosphorus availabi-lity of the Korean pine broad-leaved forests by significantly reducing the content of soil inorganic phosphorus and NaOH-P o , and such trends were positively dependent on the intensity of selective cutting.
Measuring moderate-intensity walking in older adults using the ActiGraph accelerometer.
Barnett, Anthony; van den Hoek, Daniel; Barnett, David; Cerin, Ester
2016-12-08
Accelerometry is the method of choice for objectively assessing physical activity in older adults. Many studies have used an accelerometer count cut point corresponding to 3 metabolic equivalents (METs) derived in young adults during treadmill walking and running with a resting metabolic rate (RMR) assumed at 3.5 mL · kg -1 · min -1 (corresponding to 1 MET). RMR is lower in older adults; therefore, their 3 MET level occurs at a lower absolute energy expenditure making the cut point derived from young adults inappropriate for this population. The few studies determining older adult specific moderate-to-vigorous intensity physical activity (MVPA) cut points had methodological limitations, such as not measuring RMR and using treadmill walking. This study determined a MVPA hip-worn accelerometer cut point for older adults using measured RMR and overground walking. Following determination of RMR, 45 older adults (mean age 70.2 ± 7 years, range 60-87.6 years) undertook an outdoor, overground walking protocol with accelerometer count and energy expenditure determined at five walking speeds. Mean RMR was 2.8 ± 0.6 mL · kg -1 · min -1 . The MVPA cut points (95% CI) determined using linear mixed models were: vertical axis 1013 (734, 1292) counts · min -1 ; vector magnitude 1924 (1657, 2192) counts · min -1 ; and walking speed 2.5 (2.2, 2.8) km · hr -1 . High levels of inter-individual variability in cut points were found. These MVPA accelerometer and speed cut points for walking, the most popular physical activity in older adults, were lower than those for younger adults. Using cut points determined in younger adults for older adult population studies is likely to underestimate time spent engaged in MVPA. In addition, prescription of walking speed based on the adult cut point is likely to result in older adults working at a higher intensity than intended.
Comparison of accelerometer cut points for predicting activity intensity in youth.
Trost, Stewart G; Loprinzi, Paul D; Moore, Rebecca; Pfeiffer, Karin A
2011-07-01
The absence of comparative validity studies has prevented researchers from reaching consensus regarding the application of intensity-related accelerometer cut points for children and adolescents. This study aimed to evaluate the classification accuracy of five sets of independently developed ActiGraph cut points using energy expenditure, measured by indirect calorimetry, as a criterion reference standard. A total of 206 participants between the ages of 5 and 15 yr completed 12 standardized activity trials. Trials consisted of sedentary activities (lying down, writing, computer game), lifestyle activities (sweeping, laundry, throw and catch, aerobics, basketball), and ambulatory activities (comfortable walk, brisk walk, brisk treadmill walk, running). During each trial, participants wore an ActiGraph GT1M, and V˙O2 was measured breath-by-breath using the Oxycon Mobile portable metabolic system. Physical activity intensity was estimated using five independently developed cut points: Freedson/Trost (FT), Puyau (PU), Treuth (TR), Mattocks (MT), and Evenson (EV). Classification accuracy was evaluated via weighted κ statistics and area under the receiver operating characteristic curve (ROC-AUC). Across all four intensity levels, the EV (κ=0.68) and FT (κ=0.66) cut points exhibited significantly better agreement than TR (κ=0.62), MT (κ=0.54), and PU (κ=0.36). The EV and FT cut points exhibited significantly better classification accuracy for moderate- to vigorous-intensity physical activity (ROC-AUC=0.90) than TR, PU, or MT cut points (ROC-AUC=0.77-0.85). Only the EV cut points provided acceptable classification accuracy for all four levels of physical activity intensity and performed well among children of all ages. The widely applied sedentary cut point of 100 counts per minute exhibited excellent classification accuracy (ROC-AUC=0.90). On the basis of these findings, we recommend that researchers use the EV ActiGraph cut points to estimate time spent in sedentary, light-, moderate-, and vigorous-intensity activity in children and adolescents.
Automatic liver segmentation from abdominal CT volumes using graph cuts and border marching.
Liao, Miao; Zhao, Yu-Qian; Liu, Xi-Yao; Zeng, Ye-Zhan; Zou, Bei-Ji; Wang, Xiao-Fang; Shih, Frank Y
2017-05-01
Identifying liver regions from abdominal computed tomography (CT) volumes is an important task for computer-aided liver disease diagnosis and surgical planning. This paper presents a fully automatic method for liver segmentation from CT volumes based on graph cuts and border marching. An initial slice is segmented by density peak clustering. Based on pixel- and patch-wise features, an intensity model and a PCA-based regional appearance model are developed to enhance the contrast between liver and background. Then, these models as well as the location constraint estimated iteratively are integrated into graph cuts in order to segment the liver in each slice automatically. Finally, a vessel compensation method based on the border marching is used to increase the segmentation accuracy. Experiments are conducted on a clinical data set we created and also on the MICCAI2007 Grand Challenge liver data. The results show that the proposed intensity, appearance models, and the location constraint are significantly effective for liver recognition, and the undersegmented vessels can be compensated by the border marching based method. The segmentation performances in terms of VOE, RVD, ASD, RMSD, and MSD as well as the average running time achieved by our method on the SLIVER07 public database are 5.8 ± 3.2%, -0.1 ± 4.1%, 1.0 ± 0.5mm, 2.0 ± 1.2mm, 21.2 ± 9.3mm, and 4.7 minutes, respectively, which are superior to those of existing methods. The proposed method does not require time-consuming training process and statistical model construction, and is capable of dealing with complicated shapes and intensity variations successfully. Copyright © 2017 Elsevier B.V. All rights reserved.
Evaluation of forest management practices through application of a biogeochemical model, PnET-BGC
NASA Astrophysics Data System (ADS)
Valipour, M.; Driscoll, C. T.; Johnson, C. E.; Campbell, J. L.; Fahey, T.; Zeng, T.
2017-12-01
Forest ecosystem response to logging disturbance varies significantly, depending on site conditions, species composition, land use history, and the method and frequency of harvesting. The long-term effects of forest cuttings are less clear due to limited information on land use history and long-term time series observations. The hydrochemical model, PnET-BGC was modified and verified using field data from multiple experimentally harvested northern hardwood watersheds at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, including a commercial whole-tree harvest (Watershed 5), a devegetation experiment (Watershed 2; devegetation and herbicide treatment), a commercial strip-cut (Watershed 4) to simulate the hydrology, biomass accumulation, and soil solution and stream water chemistry responses to clear-cutting. The confirmed model was used to investigate temporal changes in aboveground biomass accumulation and nutrient dynamics under three different harvesting intensities (40%, 60%, 80%) over four varied rotation lengths (20, 40, 60, 80 years) with results compared with a scenario of no forest harvesting. The total ecosystem carbon pool (biomass, soil and litter) was reduced over harvesting events. The greatest decline occurred in litter by 40%-70%, while the pool of carbon stored in aboveground biomass decreased by 30%-60% for 80% cutting levels at 40 and 20 year rotation lengths, respectively. The large pool of soil organic carbon remained relatively stable, with only minor declines over logging regimes. Stream water simulations demonstrated increased loss of major elements over cutting events. Ca+2 and NO3- were the most sensitive elements to leaching over frequent intensive logging. Accumulated leaching of Ca+2 and NO3- varied between 90-520 t Ca/ha and 40-420 t N/ha from conservative (80-year period and 40% cutting) to aggressive (20-year period and 80% cutting) cutting regimes, respectively. Moreover, a reduction in nutrient plant uptake over logging scenarios was estimated. Model simulations indicated nutrient losses were more sensitive to harvesting rotation length than intensity.
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.
Zheng, Qiang; Warner, Steven; Tasian, Gregory; Fan, Yong
2018-02-12
Automatic segmentation of kidneys in ultrasound (US) images remains a challenging task because of high speckle noise, low contrast, and large appearance variations of kidneys in US images. Because texture features may improve the US image segmentation performance, we propose a novel graph cuts method to segment kidney in US images by integrating image intensity information and texture feature maps. We develop a new graph cuts-based method to segment kidney US images by integrating original image intensity information and texture feature maps extracted using Gabor filters. To handle large appearance variation within kidney images and improve computational efficiency, we build a graph of image pixels close to kidney boundary instead of building a graph of the whole image. To make the kidney segmentation robust to weak boundaries, we adopt localized regional information to measure similarity between image pixels for computing edge weights to build the graph of image pixels. The localized graph is dynamically updated and the graph cuts-based segmentation iteratively progresses until convergence. Our method has been evaluated based on kidney US images of 85 subjects. The imaging data of 20 randomly selected subjects were used as training data to tune parameters of the image segmentation method, and the remaining data were used as testing data for validation. Experiment results demonstrated that the proposed method obtained promising segmentation results for bilateral kidneys (average Dice index = 0.9446, average mean distance = 2.2551, average specificity = 0.9971, average accuracy = 0.9919), better than other methods under comparison (P < .05, paired Wilcoxon rank sum tests). The proposed method achieved promising performance for segmenting kidneys in two-dimensional US images, better than segmentation methods built on any single channel of image information. This method will facilitate extraction of kidney characteristics that may predict important clinical outcomes such as progression of chronic kidney disease. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.
Gerbershagen, H J; Rothaug, J; Kalkman, C J; Meissner, W
2011-10-01
Cut-off points (CPs) of the numeric rating scale (NRS 0-10) are regularly used in postoperative pain treatment. However, there is insufficient evidence to identify the optimal CP between mild and moderate pain. A total of 435 patients undergoing general, trauma, or oral and maxillofacial surgery were studied. To determine the optimal CP for pain treatment, four approaches were used: first, patients estimated their tolerable postoperative pain intensity before operation; secondly, 24 h after surgery, they indicated if they would have preferred to receive more analgesics; thirdly, satisfaction with pain treatment was analysed, and fourthly, multivariate analysis was used to calculate the optimal CP for pain intensities in relation to pain-related interference with movement, breathing, sleep, and mood. The estimated tolerable postoperative pain before operation was median (range) NRS 4.0 (0-10). Patients who would have liked more analgesics reported significantly higher average pain since surgery [median NRS 5.0 (0-9)] compared with those without this request [NRS 3.0 (0-8)]. Patients satisfied with pain treatment reported an average pain intensity of median NRS 3.0 (0-8) compared with less satisfied patients with NRS 5.0 (2-9). Analysis of average postoperative pain in relation to pain-related interference with mood and activity indicated pain categories of NRS 0-2, mild; 3-4, moderate; and 5-10, severe pain. Three of the four methods identified a treatment threshold of average pain of NRS≥4. This was considered to identify patients with pain of moderate-to-severe intensity. This cut-off was indentified as the tolerable pain threshold.
NASA Astrophysics Data System (ADS)
Wei, J.; Ye, Y.; Sun, Z.; Liu, L.; Zou, G.
2016-05-01
Femtosecond laser beam cutting is becoming widely used to meet demands for increasing accuracy in micro-machining. In this paper, the effects of processing parameters in femtosecond laser beam cutting on the kerf size and microstructure in Inconel 738 have been investigated. The defocus, pulse width and scanning speed were selected to study the controllability of the cutting process. Adjusting and matching the processing parameters was a basic enhancement method to acquire well defined kerf size and the high-quality ablation of microstructures, which has contributed to the intensity clamping effect. The morphology and chemical compositions of these microstructures on the cut surface have been characterized by a scanning electron microscopy equipped with an energy dispersive X-ray spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Additionally, the material removal mechanism and oxidation mechanism on the Inconel 738 cut surface have also been discussed on the basis of the femtosecond laser induced normal vaporization or phase explosion, and trapping effect of the dangling bonds.
Gheorghe, Liana; Iacob, Speranta; Iacob, Razvan; Dumbrava, Mona; Becheanu, Gabriel; Herlea, Vlad; Gheorghe, Cristian; Lupescu, Ioana; Popescu, Irinel
2009-12-01
Small nodules (under 3 cm) detected on ultrasound (US) in cirrhotics represent the most challenging category for noninvasive diagnosis of hepatocellular carcinoma (HCC). To evaluate real-time sonoelastography as a noninvasive tool for the diagnosis of small HCC nodules in cirrhotic patients. 42 cirrhotic patients with 58 nodules (1-3 cm) were evaluated with real-time elastography (Hitachi EUB-6500); the mean intensity of colors red, blue, green were measured using a semi-quantitative method. Analysis of histograms for each color of the sonoelastography images was performed for quantifying the elasticity of nodule tissue in comparison with the cirrhotic liver tissue. AUROC curves were constructed to define the best cut-off points to distinguish malignant features of the nodules. Univariate and multivariate logistic regression analysis was performed. 595 sonoelastography images from 42 patients (25 men; 17 women) were analyzed. The mean age was 56.4 +/- 0.7 years and 69% patients were in Child-Pugh class A, 19% class B, 11% class C. For the mean intensity of green color AUROC=0.81, a cut-off value under 108.7 being diagnostic for HCC with a Sp=91.1%, Se=50%, PPV=92.1%, NPV=47.1%. Mean intensity of blue color proved to be an excellent diagnostic tool for HCC (AUROC=0.94); for a cut-off value greater than 128.9, Sp=92.2%, Se=78.9%, PPV=95.4%, NPV=68%. Independent predictive factors of HCC for a small nodule in cirrhotic patients were: blue color over 128.9 at sonoelastography and hypervascular appearance at Doppler US. US elastography is a promising method for the non-invasive diagnosis of early HCC. Blue color at elastography and hypervascular aspects are independent predictors of HCC.
Multilayer composition coatings for cutting tools: formation and performance properties
NASA Astrophysics Data System (ADS)
Tabakov, Vladimir P.; Vereschaka, Anatoly S.; Vereschaka, Alexey A.
2018-03-01
The paper considers the concept of a multi-layer architecture of the coating in which each layer has a predetermined functionality. Latest generation of coatings with multi-layered architecture for cutting tools secure a dual nature of the coating, in which coatings should not only improve the mechanical and physical characteristics of the cutting tool material, but also reduce the thermo-mechanical effect on the cutting tool determining wear intensity. Here are presented the results of the development of combined methods of forming multi-layer coatings with improved properties. Combined method of forming coatings using a pulsed laser allowed reducing excessively high levels of compressive residual stress and increasing micro hardness of the multilayered coatings. The results in testing coated HSS tools showed that the use of additional pulse of laser processing increases tool life up to 3 times. Using filtered cathodic vacuum arc deposition for the generation of multilayer coatings based on TiAlN compound has increased the wear-resistance of carbide tools by 2 fold compared with tool life of cutting tool with commercial TiN coatings. The aim of this study was to develop an innovative methodological approach to the deposition of multilayer coatings for cutting tools with functional architectural selection, properties and parameters of the coating based on sound knowledge of coating failure in machining process.
Lee, Hansang; Hong, Helen; Kim, Junmo
2014-12-01
We propose a graph-cut-based segmentation method for the anterior cruciate ligament (ACL) in knee MRI with a novel shape prior and label refinement. As the initial seeds for graph cuts, candidates for the ACL and the background are extracted from knee MRI roughly by means of adaptive thresholding with Gaussian mixture model fitting. The extracted ACL candidate is segmented iteratively by graph cuts with patient-specific shape constraints. Two shape constraints termed fence and neighbor costs are suggested such that the graph cuts prevent any leakage into adjacent regions with similar intensity. The segmented ACL label is refined by means of superpixel classification. Superpixel classification makes the segmented label propagate into missing inhomogeneous regions inside the ACL. In the experiments, the proposed method segmented the ACL with Dice similarity coefficient of 66.47±7.97%, average surface distance of 2.247±0.869, and root mean squared error of 3.538±1.633, which increased the accuracy by 14.8%, 40.3%, and 37.6% from the Boykov model, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.
Pulse Power Compression by Cutting a Dense Z-Pinch with a Laser Beam
NASA Astrophysics Data System (ADS)
Winterberg, F.
1999-07-01
A thin cut made through a z-pinch by an intense laser beam can become a magnetically insulated diode crossed by an intense ion beam. For larger cuts, the gap is crossed by an intense relativistic electron beam, stopped by magnetic bremsstrahlung resulting in a pointlike intense x-ray source. In either case, the impedance of the pinch discharge is increased, with the power delivered rising in the same pro-portion. A magnetically insulated cut is advantageous for three reasons: First, with the ion current com-parable to the Alfvèn ion current, the pinch instabilities are reduced. Second, with the energy deposit-ed into fast ions, a non-Maxwellian velocity distribution is established increasing<σ ν> value for nuclear fusion reactions taking place in the pinch discharge. Third, in a high density z-pinch plasma, the intense ion beam can launch a thermonuclear detonation wave propagating along the pinch discharge channel. For larger cuts the soft x-rays produced by magnetic bremsstrahlung can be used to drive a thermonuclear hohlraum target. Finally, the proposed pulse power compression scheme permits to use a cheap low power d.c. source charging a magnetic storage coil delivering the magnetically stored energy to the pinch discharge load by an exploding wire opening switch.
Darabant, András; Rai, Prem Bahadur; Staudhammer, Christina Lynn; Dorji, Tshewang
2016-08-01
Dendrocalamus hamiltonii, a large, clump-forming bamboo, has great potential to contribute towards poverty alleviation efforts across its distributional range. Harvesting methods that maximize yield while they fulfill local objectives and ensure sustainability are a research priority. Documenting local ecological knowledge on the species and identifying local users' goals for its production, we defined three harvesting treatments (selective cut, horseshoe cut, clear cut) and experimentally compared them with a no-intervention control treatment in an action research framework. We implemented harvesting over three seasons and monitored annually and two years post-treatment. Even though the total number of culms positively influenced the number of shoots regenerated, a much stronger relationship was detected between the number of culms harvested and the number of shoots regenerated, indicating compensatory growth mechanisms to guide shoot regeneration. Shoot recruitment declined over time in all treatments as well as the control; however, there was no difference among harvest treatments. Culm recruitment declined with an increase in harvesting intensity. When univariately assessing the number of harvested culms and shoots, there were no differences among treatments. However, multivariate analyses simultaneously considering both variables showed that harvested output of shoots and culms was higher with clear cut and horseshoe cut as compared to selective cut. Given the ease of implementation and issues of work safety, users preferred the horseshoe cut, but the lack of sustainability of shoot production calls for investigating longer cutting cycles.
Bayesian segmentation of atrium wall using globally-optimal graph cuts on 3D meshes.
Veni, Gopalkrishna; Fu, Zhisong; Awate, Suyash P; Whitaker, Ross T
2013-01-01
Efficient segmentation of the left atrium (LA) wall from delayed enhancement MRI is challenging due to inconsistent contrast, combined with noise, and high variation in atrial shape and size. We present a surface-detection method that is capable of extracting the atrial wall by computing an optimal a-posteriori estimate. This estimation is done on a set of nested meshes, constructed from an ensemble of segmented training images, and graph cuts on an associated multi-column, proper-ordered graph. The graph/mesh is a part of a template/model that has an associated set of learned intensity features. When this mesh is overlaid onto a test image, it produces a set of costs which lead to an optimal segmentation. The 3D mesh has an associated weighted, directed multi-column graph with edges that encode smoothness and inter-surface penalties. Unlike previous graph-cut methods that impose hard constraints on the surface properties, the proposed method follows from a Bayesian formulation resulting in soft penalties on spatial variation of the cuts through the mesh. The novelty of this method also lies in the construction of proper-ordered graphs on complex shapes for choosing among distinct classes of base shapes for automatic LA segmentation. We evaluate the proposed segmentation framework on simulated and clinical cardiac MRI.
Breeding bird responses to three silvicultural treatments in the Oregon Coast Range
Chambers, C.L.; McComb, W.C.; Tappeiner, J. C.
1999-01-01
Silvicultural alternatives to clear-cutting have been suggested to promote development, retention, or creation of late-successional features such as large trees, multilayered canopies, snags, and logs. We assessed bird response to three silvicultural alternatives to clear-cutting that retained structural features found in old Douglas-fir (Pseudotsuga menziesii) forests and that imitated natural disturbance regimes more closely than did traditional clear-cutting: (1) small-patch group selection treatment representing a low-intensity disturbance; (2) two-story treatment, representing a moderate to high-intensity disturbance; and (3) modified clear-cut treatment, representing a high-intensity disturbance. We counted diurnal breeding birds 1 yr prior to and 2 yr after harvest to estimate effects of the silvicultural treatments on bird communities compared with uncut controls. The small-patch group selection treatment was most similar in species composition to control stands. The two-story treatment was more similar to the modified clear-cut treatment. Ten bird species remained abundant following the small-patch group selection treatment. They declined in abundance in modified clearcuts and two-story stands. These species included four neotropical migratory species and five species with restricted geographic ranges and habitat associations. Nine species increased in response to moderate and/or high-intensity disturbances. This group included a larger proportion of species that were habitat generalists. Silvicultural treatments imitating low-intensity disturbances were most effective in retaining bird communities associated with mature forest; high-intensity disturbances such as the two-story and modified clear-cut treatments greatly altered bird community composition. Bird responses to the silvicultural treatments that we studied indicate that a variety of stand types is needed to meet needs of all species.
Combining watershed and graph cuts methods to segment organs at risk in radiotherapy
NASA Astrophysics Data System (ADS)
Dolz, Jose; Kirisli, Hortense A.; Viard, Romain; Massoptier, Laurent
2014-03-01
Computer-aided segmentation of anatomical structures in medical images is a valuable tool for efficient radiation therapy planning (RTP). As delineation errors highly affect the radiation oncology treatment, it is crucial to delineate geometric structures accurately. In this paper, a semi-automatic segmentation approach for computed tomography (CT) images, based on watershed and graph-cuts methods, is presented. The watershed pre-segmentation groups small areas of similar intensities in homogeneous labels, which are subsequently used as input for the graph-cuts algorithm. This methodology does not require of prior knowledge of the structure to be segmented; even so, it performs well with complex shapes and low intensity. The presented method also allows the user to add foreground and background strokes in any of the three standard orthogonal views - axial, sagittal or coronal - making the interaction with the algorithm easy and fast. Hence, the segmentation information is propagated within the whole volume, providing a spatially coherent result. The proposed algorithm has been evaluated using 9 CT volumes, by comparing its segmentation performance over several organs - lungs, liver, spleen, heart and aorta - to those of manual delineation from experts. A Dicés coefficient higher than 0.89 was achieved in every case. That demonstrates that the proposed approach works well for all the anatomical structures analyzed. Due to the quality of the results, the introduction of the proposed approach in the RTP process will be a helpful tool for organs at risk (OARs) segmentation.
Muránsky, Ondrej; Hamelin, Cory J.; Hosseinzadeh, F.; ...
2017-04-06
An assessment of cutting-induced plasticity (CIP) is performed, by finite element (FE) prediction of the plastic strain accumulation along the cut tip when the EDM wire sections the NeT TG4 weld benchmark specimen along two cutting directions. The first direction corresponds to a conventional (C) cutting strategy, whereby the EDM wire cuts through the thickness of the weld specimen and travels in a direction transverse to the weld. The second direction corresponds to a self-equilibrating cutting (SE) strategy, whereby the EDM wire cuts across the transverse direction of the weld specimens and travels through the thickness of the plate. Themore » cutting thus progresses simultaneously through the compression-tension-compression regions of present weld residual stress (WRS) field. This type of cutting strategy is believed to minimize the CIP by minimising residual stress redistribution during cutting, due to stress equilibration across the sectioned material. The simulated cutting procedures are conducted under a range of clamping conditions to assess whether mechanical restraint has a primary or secondary influence on CIP accumulation. Both predictions of CIP and the resultant back-calculated WRS demonstrate that (i) mechanical restraint is the primary variable influencing CIP development, and (ii) under no circumstance does a self-equilibrating cutting strategy perform significantly better than a conventional cutting approach. Furthermore, the reason that self-equilibrating cuts are not effective is illustrated by calculating the Mode I (K I) stress intensity factor (SIF) along the cut tip, and correlating trends in K I to CIP development.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muránsky, Ondrej; Hamelin, Cory J.; Hosseinzadeh, F.
An assessment of cutting-induced plasticity (CIP) is performed, by finite element (FE) prediction of the plastic strain accumulation along the cut tip when the EDM wire sections the NeT TG4 weld benchmark specimen along two cutting directions. The first direction corresponds to a conventional (C) cutting strategy, whereby the EDM wire cuts through the thickness of the weld specimen and travels in a direction transverse to the weld. The second direction corresponds to a self-equilibrating cutting (SE) strategy, whereby the EDM wire cuts across the transverse direction of the weld specimens and travels through the thickness of the plate. Themore » cutting thus progresses simultaneously through the compression-tension-compression regions of present weld residual stress (WRS) field. This type of cutting strategy is believed to minimize the CIP by minimising residual stress redistribution during cutting, due to stress equilibration across the sectioned material. The simulated cutting procedures are conducted under a range of clamping conditions to assess whether mechanical restraint has a primary or secondary influence on CIP accumulation. Both predictions of CIP and the resultant back-calculated WRS demonstrate that (i) mechanical restraint is the primary variable influencing CIP development, and (ii) under no circumstance does a self-equilibrating cutting strategy perform significantly better than a conventional cutting approach. Furthermore, the reason that self-equilibrating cuts are not effective is illustrated by calculating the Mode I (K I) stress intensity factor (SIF) along the cut tip, and correlating trends in K I to CIP development.« less
Simulation of dynamic processes when machining transition surfaces of stepped shafts
NASA Astrophysics Data System (ADS)
Maksarov, V. V.; Krasnyy, V. A.; Viushin, R. V.
2018-03-01
The paper addresses the characteristics of stepped surfaces of parts categorized as "solids of revolution". It is noted that in the conditions of transition modes during the switch to end surface machining, there is cutting with varied load intensity in the section of the cut layer, which leads to change in cutting force, onset of vibrations, an increase in surface layer roughness, a decrease of size precision, and increased wear of a tool's cutting edge. This work proposes a method that consists in developing a CNC program output code that allows one to process complex forms of stepped shafts with only one machine setup. The authors developed and justified a mathematical model of a technological system for mechanical processing with consideration for the resolution of tool movement at the stages of transition processes to assess the dynamical stability of a system in the process of manufacturing stepped surfaces of parts of “solid of revolution” type.
Zhang, Xin; Gu, Hui Yan; Chen, Xiang Wei
2018-01-01
This study examined the characteristics of phosphorus (P) adsorption and desorption in surface soil (0-10 cm) of a secondary forest after selective cutting disturbance at three levels of intensity (low, medium, high) in order to reveal the effects of different disturbance intensities on soil P adsorption and desorption. Maximum adsorption amount (Q m ), adsorption intensity factor, maximum buffer capacity, maximum desorption amount, average desorption rate and readily desorptable phosphorus were measured. Q m in the focal forests was 1383.93-1833.34 mg·kg -1 , and Q m in forests with middle and high disturbance intensities was significantly higher than that in forests with low disturbance intensity and in primary forests. P adsorption intensity was 0.024-0.059 L·mg -1 , and forests with high and low disturbance intensities increased the P adsorption intensity significantly. The maximum buffer capacity varied from 35.68 to 97.97 L·kg -1 , with the highest value found in the forest with the highest disturbance intensity. Selective cutting significantly reduced the potential for phosphorus supply in the forest soils. The maximum desorption amount, average desorption rate and readily desorptable phosphorus content in the focal forests were 526.32-797.54 mg·kg -1 , 14.7%-25.5% and 1.79-5.41 mg·kg -1 , respectively, indicating that the ability of soil to release phosphorus significantly decreased with increasing disturbance intensity. Selective cutting changed the phosphorus adsorption and desorption characteristics by reducing the supply and release of soil phosphorus.
Effect of severing method and stump height on coppice growth
John B. Crist; James A. Mattson; Sharon A. Winsauer
1983-01-01
In this study we evaluated the effect of stem severing method and stump height on coppice growth in a short-rotation intensively cultured Populus plantation 1, 2, and 3 years after cutting. Initially, stumps 46 cm high had smaller and significantly more sprouts than either 8 or 15 cm high stumps. However, the dominant sprouts were not affected by the stump height....
NASA Astrophysics Data System (ADS)
Gvozdev, S. V.; Glova, A. F.; Dubrovskii, V. Yu; Durmanov, S. T.; Krasyukov, A. G.; Lysikov, A. Yu; Smirnov, G. V.; Pleshkov, V. M.
2017-12-01
Mobile laser technological complex MLTC-20 with radiation power 20 kW and radiation wavelength 1.07 μm created in SRC RF TRINITI on the base of a three cw fiber Yb lasers is used successfully at remote cutting of the metalworks at carrying out of the emergency-reduction works on the out of control gas wells. In this work the results of the investigation of the possibility and the efficiency of laser radiation application for remote cutting of metals on the emergency oil wells have been presented. Measurements of the mean absorption coefficient of the radiation of a cw fiber Yb laser under its propagation in a flame of burning oil in dependence on radiation intensity have been carried out. It was shown that at the intensity ~104 W/cm2 the absorption coefficient traverses the maximum where its value is equal to ~0.1 cm-1, and at the intensity increasing to the values 105 - 106 W/cm2 it stabilizes on a small level ~5·10-3 - 10-2 cm-1. It is established that the maximal velocity and the efficiency of remote cutting of the steel plates with a thickness up to 10 mm by the radiation with the intensity 106 W/cm2 exceed these factors at the intensity 104 W/cm2. The possibility of the efficient remote cutting of steel plate with a thickness of 60 mm by laser radiation having the power 7.5 kW and the intensity 105 W/cm2 has been demonstrated.
46 CFR 164.018-11 - Approval tests.
Code of Federal Regulations, 2012 CFR
2012-10-01
... the following test methods described in Federal Specification L-S-300: (1) Test conditions. (2) Test... sharp knife from each corner to the corner diagonally opposite so that an “X” is formed. The cuts must...— (1) The L-S-300 procedure for measuring reflective intensity; or (2) The procedure for measuring...
46 CFR 164.018-11 - Approval tests.
Code of Federal Regulations, 2010 CFR
2010-10-01
... the following test methods described in Federal Specification L-S-300: (1) Test conditions. (2) Test... sharp knife from each corner to the corner diagonally opposite so that an “X” is formed. The cuts must...— (1) The L-S-300 procedure for measuring reflective intensity; or (2) The procedure for measuring...
46 CFR 164.018-11 - Approval tests.
Code of Federal Regulations, 2011 CFR
2011-10-01
... the following test methods described in Federal Specification L-S-300: (1) Test conditions. (2) Test... sharp knife from each corner to the corner diagonally opposite so that an “X” is formed. The cuts must...— (1) The L-S-300 procedure for measuring reflective intensity; or (2) The procedure for measuring...
46 CFR 164.018-11 - Approval tests.
Code of Federal Regulations, 2014 CFR
2014-10-01
... the following test methods described in Federal Specification L-S-300: (1) Test conditions. (2) Test... sharp knife from each corner to the corner diagonally opposite so that an “X” is formed. The cuts must...— (1) The L-S-300 procedure for measuring reflective intensity; or (2) The procedure for measuring...
46 CFR 164.018-11 - Approval tests.
Code of Federal Regulations, 2013 CFR
2013-10-01
... the following test methods described in Federal Specification L-S-300: (1) Test conditions. (2) Test... sharp knife from each corner to the corner diagonally opposite so that an “X” is formed. The cuts must...— (1) The L-S-300 procedure for measuring reflective intensity; or (2) The procedure for measuring...
NASA Astrophysics Data System (ADS)
Gets, A. V.; Krainov, V. P.
2018-01-01
The yield of spontaneous photons at the tunneling ionization of atoms by intense low-frequency laser radiation near the classical cut-off is estimated analytically by using the three-step model. The Bell-shaped dependence in the universal photon spectrum is explained qualitatively.
Tombesi, Sergio; Palliotti, Alberto; Poni, Stefano; Farinelli, Daniela
2015-01-01
Adventitious root formation in plant cuttings is influenced by many endogenous and environmental factors. Leaf photosynthesis during rooting of leafy cuttings in hard to root species can contribute to supply carbohydrates to the intensive metabolic processes related to adventious root formation. Light intensity during rooting is artificially kept low to decrease potential cutting desiccation, but can be limiting for photosynthetic activity. Furthermore, leafy cuttings collected from different part of the shoot can have a different ability to fuel adventitious root formation in cutting stem. The aim of this work was to determine the role of leaf photosynthesis on adventitious root formation in hazelnut (Corylus avellana L) (a hard-to-root specie) leafy cuttings and to investigate the possible influence of the shoot developmental stage on cutting rooting and survival in the post-rooting phase. Cutting rooting was closely related to carbohydrate content in cutting stems during the rooting process. Cutting carbohydrate status was positively influenced by leaf photosynthesis during rooting. Non-saturating light exposure of leafy cuttings can contribute to improve photosynthetic activity of leafy cuttings. Collection of cuttings from different part of the mother shoots influenced rooting percentage and this appear related to the different capability to concentrate soluble sugars in the cutting stem during rooting. Adventitious root formation depend on the carbohydrate accumulation at the base of the cutting. Mother shoot developmental stage and leaf photosynthesis appear pivotal factors for adventitious roots formation. PMID:26635821
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.
Nakajima, Nobuharu
2010-07-20
When a very intense beam is used for illuminating an object in coherent x-ray diffraction imaging, the intensities at the center of the diffraction pattern for the object are cut off by a beam stop that is utilized to block the intense beam. Until now, only iterative phase-retrieval methods have been applied to object reconstruction from a single diffraction pattern with a deficiency of central data due to a beam stop. As an alternative method, I present a noniterative solution in which an interpolation method based on the sampling theorem for the missing data is used for object reconstruction with our previously proposed phase-retrieval method using an aperture-array filter. Computer simulations demonstrate the reconstruction of a complex-amplitude object from a single diffraction pattern with a missing data area, which is generally difficult to treat with the iterative methods because a nonnegativity constraint cannot be used for such an object.
Lung vessel segmentation in CT images using graph-cuts
NASA Astrophysics Data System (ADS)
Zhai, Zhiwei; Staring, Marius; Stoel, Berend C.
2016-03-01
Accurate lung vessel segmentation is an important operation for lung CT analysis. Filters that are based on analyzing the eigenvalues of the Hessian matrix are popular for pulmonary vessel enhancement. However, due to their low response at vessel bifurcations and vessel boundaries, extracting lung vessels by thresholding the vesselness is not sufficiently accurate. Some methods turn to graph-cuts for more accurate segmentation, as it incorporates neighbourhood information. In this work, we propose a new graph-cuts cost function combining appearance and shape, where CT intensity represents appearance and vesselness from a Hessian-based filter represents shape. Due to the amount of voxels in high resolution CT scans, the memory requirement and time consumption for building a graph structure is very high. In order to make the graph representation computationally tractable, those voxels that are considered clearly background are removed from the graph nodes, using a threshold on the vesselness map. The graph structure is then established based on the remaining voxel nodes, source/sink nodes and the neighbourhood relationship of the remaining voxels. Vessels are segmented by minimizing the energy cost function with the graph-cuts optimization framework. We optimized the parameters used in the graph-cuts cost function and evaluated the proposed method with two manually labeled sub-volumes. For independent evaluation, we used 20 CT scans of the VESSEL12 challenge. The evaluation results of the sub-volume data show that the proposed method produced a more accurate vessel segmentation compared to the previous methods, with F1 score 0.76 and 0.69. In the VESSEL12 data-set, our method obtained a competitive performance with an area under the ROC curve of 0.975, especially among the binary submissions.
Sensitivity of allowable cuts to intensive management.
Roger D. Fight; Dennis L. Schweitzer
1974-01-01
A sensitivity analysis of allowable cuts on two BLM master units shows that even-flow allowable cuts depend primarily on: (1) assumed long-term growth potential, (2) period that growth increases must be cumulated before they can be removed from the stands on which they occur, and (3) amount and age-class distribution of the initial inventory. Current allowable cut...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bahadur, A.; Yadav, R.S.; Yadav, R.V.
This paper reports the optical properties of Tb{sup 3+}/Yb{sup 3+} co-doped lithium borate (LB) glass prepared by melt quench method. The absorption spectrum of the Yb{sup 3+} doped LB glass contains intense NIR band centered at 976 nm due to {sup 2}F{sub 7/2}→{sup 2}F{sub 5/2} transition. The emission spectra of the prepared glasses have been monitored on excitation with 266, 355 and 976 nm. The Yb{sup 3+} doped glass emits a broad NIR band centered at 976 nm whereas the Tb{sup 3+} doped glass gives off visible bands on excitations with 266 and 355 nm. When the Tb{sup 3+} andmore » Yb{sup 3+} ions are co-doped together, the emission intensity in the visible region decreases whereas it increases in the NIR region significantly. The increase in the emission intensity in the NIR region is due to efficient cooperative energy transfer (CET) from Tb{sup 3+} to Yb{sup 3+} ions. The quantum cutting efficiency for Tb{sup 3+}/Yb{sup 3+} co-doped glass has been calculated and compared for 266 and 355 nm excitations. The quantum cutting efficiency is larger for 355 nm excitation (137%). The Tb{sup 3+}/Yb{sup 3+} co-doped LB glass also emits upconverted visible bands on excitation with 976 nm. The mechanisms involved in the energy transfer have been discussed using schematic energy level diagram. The Tb{sup 3+}/Yb{sup 3+} co-doped LB glass may be used in the optical devices and in solar cell for solar spectral conversion and behaves as a multi-modal photo-luminescent material. - Graphical abstract: The Tb{sup 3+}/Yb{sup 3+} co-doped lithium borate (LB) glass prepared by melt quench method emits upconverted visible emissions through upconversion CET from Yb{sup 3+} to Tb{sup 3+} ions and quantum cutting emissions through downconversion CET from Tb{sup 3+} to Yb{sup 3+} ions. Therefore, the Tb{sup 3+}/Yb{sup 3+} co-doped LB glass may find applications in optical devices and solar cell and behaves as a multi-modal photo-luminescent material. - Highlights: • The Tb{sup 3+}/Yb{sup 3+} co-doped lithium borate (LB) glass prepared by melt quench method. • The Tb{sup 3+}/Yb{sup 3+} co-doped glass gives QC emissions upon 266 and 355 nm excitations. • The Tb{sup 3+}/Yb{sup 3+} co-doped glass also emits intense green color on excitation with 976 nm. • The quantum cutting efficiency is larger for 355 nm excitation (137%). • The Tb{sup 3+}/Yb{sup 3+} co-doped glass may be used in solar cell and display devices.« less
Clearcutting and natural regeneration: management implications for the northern Sierra Nevada
Philip M. McDonald
1983-01-01
In the young-mature mixed-conifer and hardwood forests of north-central California, a dense and persistent hardwood understory competes with the conifers for space, nutrients, and water. Clear-cutting with intensive site preparation often is the most appropriate silvicultural regeneration method. This report, the result of 20 years of research on the Challenge...
Logging slash flammability after five years
George R. Fahnestock; John H. Dieterich
1962-01-01
This paper reports the final phase of research that has determined the flammability of slash for nine species of northern Rocky Mountain conifers at three ages. Visual characteristics, rate of fire spread, and fire intensity for 5-year-old slash were studied by essentially the same methods as had been used previously on freshly cut and 1-year-old material. Final...
The best of both worlds: automated CMP polishing of channel-cut monochromators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kasman, Elina; Erdmann, Mark; Stoupin, Stanislav
2015-09-03
The use of a channel-cut monochromator is the most straightforward method to ensure that the two reflection surfaces maintain alignment between crystallographic planes without the need for complicated alignment mechanisms. Three basic characteristics that affect monochromator performance are: subsurface damage which contaminates spectral purity; surface roughness which reduces efficiency due to scattering; and surface figure error which imparts intensity structure and coherence distortion in the beam. Standard chemical-mechanical polishing processes and equipment are used when the diffracting surface is easily accessible, such as for single-bounce monochromators. Due to the inaccessibly of the surfaces inside a channel-cut monochromator for polishing, thesemore » optics are generally wet-etched for their final processing. This results in minimal subsurface damage, but very poor roughness and figure error. A new CMP channel polishing instrument design is presented which allows the internal diffracting surface quality of channel-cut crystals to approach that of conventional single-bounce monochromators« less
Laser Cutting of Thin Nickel Bellows
NASA Technical Reports Server (NTRS)
Butler, C. L.
1986-01-01
Laser cutting technique produces narrow, precise, fast, and repeatable cuts in thin nickel-allow bellows material. Laser cutting operation uses intense focused beam to melt material and assisting gas to force melted material through part thickness, creating void. When part rotated or moved longitudinally, melting and material removal continuous and creates narrow, fast, precise, and repeatable cut. Technique used to produce cuts of specified depths less than material thickness. Avoids distortion, dents, and nicks produced in delicate materials during lathe trimming operations, which require high cutting-tool pressure and holding-fixture forces.
User's manual for a computer program for simulating intensively managed allowable cut.
Robert W. Sassaman; Ed Holt; Karl Bergsvik
1972-01-01
Detailed operating instructions are described for SIMAC, a computerized forest simulation model which calculates the allowable cut assuming volume regulation for forests with intensively managed stands. A sample problem illustrates the required inputs and expected output. SIMAC is written in FORTRAN IV and runs on a CDC 6400 computer with a SCOPE 3.3 operating system....
Liu, Ying; Xu, Yi; Cheng, Wen; Liu, Xinghan
2016-01-01
The present study aimed to investigate the feasibility of applying contrast-enhanced ultrasonography (CEUS) imaging technology for distinguishing between benign and malignant endometrial lesions, and to screen markers that could be correlated with the pathological results. In this study, endometrial diseases were diagnosed by biopsy under hysteroscopy and CEUS examinations. The intensity and time parameters of the time-intensity curve (TIC) were analyzed. The mean arrival time (AT), time-to-peak (TTP), rise time (RT), washout half-time and clearance half-time of malignant lesions were shorter than those of benign lesions (P<0.05), whereas the average peak intensity (PI) and enhancement intensity (EI) of malignant lesions were higher than those of benign lesions (P<0.05). The receiver operating characteristic curve showed the following cut-off values: PI, 29.2 dB; EI, 21.35 dB; AT, 12.75 sec; TTP, 26.75 sec; RT, 13.2 sec; clearance half-time, 89.3 sec; and washout half-time, 75.45 sec. The lesions with PI, an EI higher than that of the cut-off and lesions with an AT, TTP, RT, half clearing time and washout half-time shorter than the cut-off were considered malignant. The TTP, RT and half clearing time were negatively correlated with microvessel density (MVD), i.e., MVD was higher when the TTP, RT and half clearing time were shorter. Overall, changes in the enhancement and clearing of lesions could be quantitatively analyzed by CEUS TIC and further discriminate benign from malignant lesions. In the present study, CEUS appeared to indirectly reflect blood vessel changes inside the lesions and provided a pre-operative non-invasive fast imaging method for the diagnosis of endometrial disease. PMID:27895728
Vähä-Ypyä, Henri; Vasankari, Tommi; Husu, Pauliina; Suni, Jaana; Sievänen, Harri
2015-01-01
Accelerometers are increasingly used for objective assessment of physical activity. However, because of lack of the proprietary analysis algorithms, direct comparisons between accelerometer brands are difficult. In this study, we propose and evaluate open source methods for commensurate assessment of raw accelerometer data irrespective of the brand. Twenty-one participants carried simultaneously three different tri-axial accelerometers on their waist during five different sedentary activities and five different intensity levels of bipedal movement from slow walking to running. Several time and frequency domain traits were calculated from the measured raw data, and their performance in classifying the activities was compared. Of the several traits, the mean amplitude deviation (MAD) provided consistently the best performance in separating the sedentary activities and different speeds of bipedal movement from each other. Most importantly, the universal cut-off limits based on MAD classified sedentary activities and different intensity levels of walking and running equally well for all three accelerometer brands and reached at least 97% sensitivity and specificity in each case. Irrespective of the accelerometer brand, a simply calculable MAD with universal cut-off limits provides a universal method to evaluate physical activity and sedentary behaviour using raw accelerometer data. A broader application of the present approach is expected to render different accelerometer studies directly comparable with each other. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.
The Grand Challenge: Helping Teachers Learn/Teach Cutting-Edge Science via a PBL Approach
ERIC Educational Resources Information Center
Ertmer, Peggy A.; Schlosser, Sarah; Clase, Kari; Adedokun, Omolola
2014-01-01
A mixed-methods research study was designed to examine teachers' knowledge and confidence for implementing a STEM-based problem-based learning (PBL) unit in their 6-12 grade science and math classrooms. Twenty-one teachers (7 in-service and 13 pre-service) participated in an intensive two-week summer workshop during which they engaged in, and then…
Influence of Weathering Depth and Fracture Intensity to Cut-slope Movements
NASA Astrophysics Data System (ADS)
Yoon, W. S.; Choi, J. W.; Jeong, U.; Kim, J. H.
2003-04-01
Generally, Failure modes in cut slopes are triggered by combination of various failure factors which have different effects on failure modes according to ground condition. It is, therefore, important to identify the behavioural characteristic of cut slope in that they reflect the failure mechanism. From the careful field investigation for 373 road cuts along the national highway in Korea, we analysed various types of failure modes for different ground conditions. The ground conditions which control failure modes of cut slopes and their related failure factors are dependent on weathering (or soil) depth and intensity of discontinuities in cut slopes. Firstly, the ratio of the soil depth and slope height (soil depth ratio; SR) is important parameter to classify ground conditions into soil-like masses and rock masses. When a SR value is greater than 0.4, sliding failures on discontinuities do not occur. In this case, weathering condition, slope gradient and external rainfall play a key role on failure factors of cut-slope. The proposed 0.4, therefore, is the critical SR value to identify the soil-like masses and rock masses. Secondly, Intensity of discontinuities is expressed by block size ratio (BR), which is defined by the ratio of block size index (Ib; ISRM (1978)) and slope height. For a rock slope (SR<0.4), when BR is greater than 0.01, key failure modes in a cut slope are wedge sliding, fall and topple. In this case, attitudes and shear strength of discontinuities play an important role on behaviour of cut-slope. When BR is less than 0.01, however, behaviour of cut slope shows circular sliding and surface failure like soil-like mass. To sum up, we could divide the ground conditions in cut-slope into 3 classes on the basis of SR (soil depth ratio) and BR (block size ratio); JRM (joint rock mass), HRM (highly fractured rock mass) and SLM (soil-like mass). Moreover, to evaluate the stability of cut-slope reasonably, it needs new evaluating categories having different weighting factors for each ground condition.
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.
Roscoe, Clare M P; James, Rob S; Duncan, Michael J
2017-08-01
This study sought to validate cut-points for use of wrist-worn GENEActiv accelerometer data, to analyse preschool children's (4 to 5 year olds) physical activity (PA) levels via calibration with oxygen consumption values (VO 2 ). This was a laboratory-based calibration study. Twenty-one preschool children, aged 4.7 ± 0.5 years old, completed six activities (ranging from lying supine to running) whilst wearing the GENEActiv accelerometers at two locations (left and right wrist), these being the participants' non-dominant and dominant wrist, and a Cortex face mask for gas analysis. VO 2 data was used for the assessment of criterion validity. Location specific activity intensity cut-points were established via receiver operator characteristic curve (ROC) analysis. The GENEActiv accelerometers, irrespective of their location, accurately discriminated between all PA intensities (sedentary, light, and moderate and above), with the dominant wrist monitor providing a slightly more precise discrimination at light PA and the non-dominant at the sedentary behaviour and moderate and above intensity levels (area under the curve (AUC) for non-dominant = 0.749-0.993, compared to AUC dominant = 0.760-0.988). This study establishes wrist-worn physical activity cut-points for the GENEActiv accelerometer in preschoolers. What is Known: • GENEActiv accelerometers have been validated as a PA measurement tool in adolescents and adults. • No study to date has validated the GENEActiv accelerometers in preschoolers. What is New: • Cut-points were determined for the wrist-worn GENEActiv accelerometer in preschoolers. • These cut-points can be used in future research to help classify and increase preschoolers' compliance rates with PA.
Quantitative analysis of airway abnormalities in CT
NASA Astrophysics Data System (ADS)
Petersen, Jens; Lo, Pechin; Nielsen, Mads; Edula, Goutham; Ashraf, Haseem; Dirksen, Asger; de Bruijne, Marleen
2010-03-01
A coupled surface graph cut algorithm for airway wall segmentation from Computed Tomography (CT) images is presented. Using cost functions that highlight both inner and outer wall borders, the method combines the search for both borders into one graph cut. The proposed method is evaluated on 173 manually segmented images extracted from 15 different subjects and shown to give accurate results, with 37% less errors than the Full Width at Half Maximum (FWHM) algorithm and 62% less than a similar graph cut method without coupled surfaces. Common measures of airway wall thickness such as the Interior Area (IA) and Wall Area percentage (WA%) was measured by the proposed method on a total of 723 CT scans from a lung cancer screening study. These measures were significantly different for participants with Chronic Obstructive Pulmonary Disease (COPD) compared to asymptomatic participants. Furthermore, reproducibility was good as confirmed by repeat scans and the measures correlated well with the outcomes of pulmonary function tests, demonstrating the use of the algorithm as a COPD diagnostic tool. Additionally, a new measure of airway wall thickness is proposed, Normalized Wall Intensity Sum (NWIS). NWIS is shown to correlate better with lung function test values and to be more reproducible than previous measures IA, WA% and airway wall thickness at a lumen perimeter of 10 mm (PI10).
Shoot position affects root initiation and growth of dormant unrooted cuttings of Populus
R.S., Jr. Zalesny; R.B. Hall; E.O. Bauer; D.E. Riemenschneider
2003-01-01
Rooting of dormant unrooted cuttings is crucial to the commercial deployment of intensively cultured poplar (Populus spp.) plantations because it is the first biological prerequisite to stand establishment. Rooting can be genetically controlled and subject to selection. Thus, our objective was to test for differences in rooting ability among cuttings...
33 CFR 84.17 - Horizontal sectors.
Code of Federal Regulations, 2010 CFR
2010-07-01
... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside the... intensity may decrease by 50 percent up to the prescribed limits; it shall decrease steadily to reach...
Vähä-Ypyä, Henri; Vasankari, Tommi; Husu, Pauliina; Mänttäri, Ari; Vuorimaa, Timo; Suni, Jaana; Sievänen, Harri
2015-01-01
Our recent study of three accelerometer brands in various ambulatory activities showed that the mean amplitude deviation (MAD) of the resultant acceleration signal performed best in separating different intensity levels and provided excellent agreement between the three devices. The objective of this study was to derive a regression model that estimates oxygen consumption (VO2) from MAD values and validate the MAD-based cut-points for light, moderate and vigorous locomotion against VO2 within a wide range of speeds. 29 participants performed a pace-conducted non-stop test on a 200 m long indoor track. The initial speed was 0.6 m/s and it was increased by 0.4 m/s every 2.5 minutes until volitional exhaustion. The participants could freely decide whether they preferred to walk or run. During the test they carried a hip-mounted tri-axial accelerometer and mobile metabolic analyzer. The MAD was calculated from the raw acceleration data and compared to directly measured incident VO2. Cut-point between light and moderate activity was set to 3.0 metabolic equivalent (MET, 1 MET = 3.5 ml · kg-1 · min-1) and between moderate and vigorous activity to 6.0 MET as per standard use. The MAD and VO2 showed a very strong association. Within individuals, the range of r values was from 0.927 to 0.991 providing the mean r = 0.969. The optimal MAD cut-point for 3.0 MET was 91 mg (milligravity) and 414 mg for 6.0 MET. The present study showed that the MAD is a valid method in terms of the VO2 within a wide range of ambulatory activities from slow walking to fast running. Being a device-independent trait, the MAD facilitates directly comparable, accurate results on the intensity of physical activity with all accelerometers providing tri-axial raw data.
30 CFR 75.1719-3 - Methods of measurement; light measuring instruments.
Code of Federal Regulations, 2010 CFR
2010-07-01
... §§ 75.1719.1(e)(1) through 75.1719-1(e)(3) luminous intensity measurements of the face, ribs, roof... approximate center of the working place with the cutting, loading, or drilling head toward the face and not more than 3 feet from the face. (2) In areas of working places specified in § 75.1719-1(e)(4) luminous...
30 CFR 75.1719-3 - Methods of measurement; light measuring instruments.
Code of Federal Regulations, 2013 CFR
2013-07-01
... §§ 75.1719.1(e)(1) through 75.1719-1(e)(3) luminous intensity measurements of the face, ribs, roof... approximate center of the working place with the cutting, loading, or drilling head toward the face and not more than 3 feet from the face. (2) In areas of working places specified in § 75.1719-1(e)(4) luminous...
30 CFR 75.1719-3 - Methods of measurement; light measuring instruments.
Code of Federal Regulations, 2014 CFR
2014-07-01
... §§ 75.1719.1(e)(1) through 75.1719-1(e)(3) luminous intensity measurements of the face, ribs, roof... approximate center of the working place with the cutting, loading, or drilling head toward the face and not more than 3 feet from the face. (2) In areas of working places specified in § 75.1719-1(e)(4) luminous...
30 CFR 75.1719-3 - Methods of measurement; light measuring instruments.
Code of Federal Regulations, 2012 CFR
2012-07-01
... §§ 75.1719.1(e)(1) through 75.1719-1(e)(3) luminous intensity measurements of the face, ribs, roof... approximate center of the working place with the cutting, loading, or drilling head toward the face and not more than 3 feet from the face. (2) In areas of working places specified in § 75.1719-1(e)(4) luminous...
30 CFR 75.1719-3 - Methods of measurement; light measuring instruments.
Code of Federal Regulations, 2011 CFR
2011-07-01
... §§ 75.1719.1(e)(1) through 75.1719-1(e)(3) luminous intensity measurements of the face, ribs, roof... approximate center of the working place with the cutting, loading, or drilling head toward the face and not more than 3 feet from the face. (2) In areas of working places specified in § 75.1719-1(e)(4) luminous...
The longitudinal development of muons in cosmic ray air showers at energies 10(15) - 10(17) eV
NASA Technical Reports Server (NTRS)
1985-01-01
The relationship between longitudinal development of muons and conventional equi-intensity cuts is carefully investigated. The development of muons in Extensive Air Showers (EAS) has been calculated using simulation with a scaling violation model at the highest energies and mixed primary composition. Profiles of equi-intensity cuts expected at observation altitudes of 550, 690 and 930/sq cm can fit the observed data very well.
Improvements of high-power diode laser line generators open up new application fields
NASA Astrophysics Data System (ADS)
Meinschien, J.; Bayer, A.; Bruns, P.; Aschke, L.; Lissotschenko, V. N.
2009-02-01
Beam shaping improvements of line generators based on high power diode lasers lead to new application fields as hardening, annealing or cutting of various materials. Of special interest is the laser treatment of silicon. An overview of the wide variety of applications is presented with special emphasis of the relevance of unique laser beam parameters like power density and beam uniformity. Complementary to vision application and plastic processing, these new application markets become more and more important and can now be addressed by high power diode laser line generators. Herewith, a family of high power diode laser line generators is presented that covers this wide spectrum of application fields with very different requirements, including new applications as cutting of silicon or glass, as well as the beam shaping concepts behind it. A laser that generates a 5m long and 4mm wide homogeneous laser line is shown with peak intensities of 0.2W/cm2 for inspection of railway catenaries as well as a laser that generates a homogeneous intensity distribution of 60mm x 2mm size with peak intensities of 225W/cm2 for plastic processing. For the annealing of silicon surfaces, a laser was designed that generates an extraordinary uniform intensity distribution with residual inhomogeneities (contrast ratio) of less than 3% over a line length of 11mm and peak intensities of up to 75kW/cm2. Ultimately, a laser line is shown with a peak intensity of 250kW/cm2 used for cutting applications. Results of various application tests performed with the above mentioned lasers are discussed, particularly the surface treatment of silicon and the cutting of glass.
Effect of cutting parameters on strain hardening of nickel–titanium shape memory alloy
NASA Astrophysics Data System (ADS)
Wang, Guijie; Liu, Zhanqiang; Ai, Xing; Huang, Weimin; Niu, Jintao
2018-07-01
Nickel–titanium shape memory alloy (SMA) has been widely used as implant materials due to its good biocompatibility, shape memory property and super-elasticity. However, the severe strain hardening is a main challenge due to cutting force and temperature caused by machining. An orthogonal experiment of nickel–titanium SMA with different milling parameters conditions was conducted in this paper. On the one hand, the effect of cutting parameters on work hardening is obtained. It is found that the cutting speed has the most important effect on work hardening. The depth of machining induced layer and the degree of hardening become smaller with the increase of cutting speed when the cutting speed is less than 200 m min‑1 and then get larger with further increase of cutting speed. The relative intensity of diffraction peak increases as the cutting speed increase. In addition, all of the depth of machining induced layer, the degree of hardening and the relative intensity of diffraction peak increase when the feed rate increases. On the other hand, it is found that the depth of machining induced layer is closely related with the degree of hardening and phase transition. The higher the content of austenite in the machined surface is, the higher the degree of hardening will be. The depth of the machining induced layer increases with the degree of hardening increasing.
Interaction of beaver and elk herbivory reduces standing crop of willow
Baker, B.W.; Mitchell, D.C.S.; Ducharme, H.C.; Stanley, T.R.; Peinetti, H.R.
2005-01-01
Populations of beaver and willow have not thrived in riparian environments that are heavily browsed by livestock or ungulates, such as elk. The interaction of beaver and elk herbivory may be an important mechanism underlying beaver and willow declines in this competitive environment. We conducted a field experiment that compared the standing crop of willow three years after simulated beaver cutting on paired plants with and without intense elk browsing (∼85% utilization rate). Simulated beaver cutting with intense elk browsing produced willow that was small (biomass and diameter) and short, with far fewer, but longer, shoots and a higher percentage of dead biomass. In contrast, simulated beaver cutting without elk browsing produced willow that was large, tall, and leafy, with many more, but shorter, shoots (highly branched) and a lower percentage of dead biomass. Total stem biomass after three years was 10 times greater on unbrowsed plants than on browsed plants. Unbrowsed plants recovered 84% of their pre-cut biomass after only two growing seasons, whereas browsed plants recovered only 6%. Thus, the interaction of beaver cutting and elk browsing strongly suppressed the standing crop of willow. We predict that a lack of willow suitable as winter food for beaver can cause beaver populations to decline, creating a feedback mechanism that reduces beaver and willow populations. Thus, intense herbivory by ungulates or livestock can disrupt beaver–willow mutualisms that naturally occur in less competitive environments.
Sabzehei, Faezeh; Kouhpayeh, Shirin; Dastjerdeh, Mansoureh Shahbazi; Khanahmad, Hossein; Salehi, Rasoul; Naderi, Shamsi; Taghizadeh, Razieh; Rabiei, Parisa; Hejazi, Zahra; Shariati, Laleh
2017-01-01
Background: Gene editing technology has created a revolution in the field of genome editing. The three of the most famous tools in gene editing technology are zinc finger nucleases (ZFNs), transcription activator-like effector nucleases, clustered regularly interspaced short palindromic repeats (CRISPR), and CRISPR-associated systems. As their predictable nature, it is necessary to assess their efficiency. There are some methods for this purpose, but most of them are time labor and complicated. Here, we introduce a new prokaryotic reporter system, which makes it possible to evaluate the efficiency of gene editing tools faster, cheaper, and simpler than previous methods. Materials and Methods: At first, the target sites of a custom ZFN, which is designed against a segment of ampicillin resistance gene, were cloned on both sides of green fluorescent protein (GFP) gene to construct pPRO-GFP. Then pPRO-GFP was transformed into Escherichia coli TOP10F’ that contains pZFN (contains expression cassette of a ZFN against ampicillin resistant gene), or p15A-KanaR as a negative control. The transformed bacteria were cultured on three separate media that contained ampicillin, kanamycin, and ampicillin + kanamycin; then the resulted colonies were assessed by flow cytometry. Results: The results of flow cytometry showed a significant difference between the case (bacteria contain pZFN) and control (bacteria contain p15A, KanaR) in MFI (Mean Fluorescence Intensity) (P < 0.0001). Conclusion: According to ZFN efficiency, it can bind and cut the target sites, the bilateral cutting can affect the intensity of GFP fluorescence. Our flow cytometry results showed that this ZFN could reduce the intensity of GFP color and colony count of bacteria in media containing amp + kana versus control sample. PMID:29285485
Wang, Siqin; Qiu, Jianbei; Wang, Qi; Zhou, Dacheng; Yang, Zhengwen
2015-08-01
YPO4: Tm, Yb inverse opal photonic crystals were successfully synthesized by the colloidal crystal templates method, and the visible-infrared quantum cutting (QC) photoluminescence properties of YPO4: Tm, Yb inverse opal photonic crystals were investigated. We obtained tetragonal phase YPO4 in all the samples when the samples sintered at 950°C for 5 h. The visible emission intensity of Tm3+ decreased significantly when the photonic bandgap was located at 650 nm under 480 nm excitation. On the contrary, the QC emission intensity of Yb3+ was enhanced as compared with the no photonic bandgap sample. When the photonic bandgap was located at 480 nm, the Yb3+ and Tm3+ light-emitting intensity weakened at the same time. We demonstrated that the energy transfer between Tm3+ and Yb3+ is enhanced by the suppression of the red emission of Tm3+. Additionally, the mechanisms for the influence of the photonic bandgap on the energy transfer process of the Tm3+, Yb3+ codoped YPO4 inverse opal are discussed.
NASA Astrophysics Data System (ADS)
Huang, Kai; Jia, Qi; You, Tiangui; Zhang, Shibin; Lin, Jiajie; Zhang, Runchun; Zhou, Min; Yu, Wenjie; Zhang, Bo; Ou, Xin; Wang, Xi
2017-09-01
Cross-sectional Raman spectroscopy is used to characterize the defect formation and the defect recovery in MeV H+ implanted bulk GaN and 4H-SiC in the high energy MeV ion-cut process. The Raman intensity decreases but the forbidden modes are activated at the damage region, and the intensity decrease is proportional to the damage level. The Raman spectrum is quite sensitive to detect the damage recovery after annealing. The main peak intensity increases and the forbidden mode disappears in both annealed GaN and 4H-SiC samples. The Raman spectra of GaN samples annealed at different temperatures suggest that higher annealing temperature is more efficient for damage recovery. While, the Raman spectra of SiC indicate that higher implantation temperature results in heavier lattice damage and other polytype clusters might be generated by high annealing temperature in the annealed SiC samples. The cross-sectional Raman spectroscopy is a straightforward method to characterize lattice damage and damage recovery in high energy ion-cut process. It can serve as a fast supplementary measurement technique to Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA) and transmission electron microscope (TEM) for the defect characterizations.
NASA Astrophysics Data System (ADS)
Wang, Zhiguo; Liang, Yingchun; Chen, Mingjun; Tong, Zhen; Chen, Jiaxuan
2010-10-01
Tool wear not only changes its geometry accuracy and integrity, but also decrease machining precision and surface integrity of workpiece that affect using performance and service life of workpiece in ultra-precision machining. Scholars made a lot of experimental researches and stimulant analyses, but there is a great difference on the wear mechanism, especially on the nano-scale wear mechanism. In this paper, the three-dimensional simulation model is built to simulate nano-metric cutting of a single crystal silicon with a non-rigid right-angle diamond tool with 0 rake angle and 0 clearance angle by the molecular dynamics (MD) simulation approach, which is used to investigate the diamond tool wear during the nano-metric cutting process. A Tersoff potential is employed for the interaction between carbon-carbon atoms, silicon-silicon atoms and carbon-silicon atoms. The tool gets the high alternating shear stress, the tool wear firstly presents at the cutting edge where intension is low. At the corner the tool is splitted along the {1 1 1} crystal plane, which forms the tipping. The wear at the flank face is the structure transformation of diamond that the diamond structure transforms into the sheet graphite structure. Owing to the tool wear the cutting force increases.
An interferometer having fused optical fibers, and apparatus and method using the interferometer
NASA Technical Reports Server (NTRS)
Hellbaum, Richard F. (Inventor); Claus, Richard O. (Inventor); Murphy, Kent A. (Inventor); Gunther, Michael F. (Inventor)
1992-01-01
An interferometer includes a first optical fiber coupled to a second optical fiber by fusing. At a fused portion, the first and second optical fibers are cut to expose respective cores. The cut or fused end of the first and second optical fibers is arranged to oppose a diaphragm or surface against which a physical phenomenon such as pressure or stress, is applied. In a first embodiment, a source light which is generally single-mode monochromatic, coherent light, is input to the first optical fiber and by evanescence, effectively crosses to the second optical fiber at the fused portion. Source light from the second optical fiber is reflected by the diaphragm or surface, and received at the second optical fiber to generate an output light which has an intensity which depends upon interference of reference light based on the source light, and the reflected light reflected from the diaphragm or surface. The intensity of the output light represents a positional relationship or displacement between the interferometer and the diaphragm or surface.
Identification of Tool Wear when Machining of Austenitic Steels and Titatium by Miniature Machining
NASA Astrophysics Data System (ADS)
Pilc, Jozef; Kameník, Roman; Varga, Daniel; Martinček, Juraj; Sadilek, Marek
2016-12-01
Application of miniature machining is currently rapidly increasing mainly in biomedical industry and machining of hard-to-machine materials. Machinability of materials with increased level of toughness depends on factors that are important in the final state of surface integrity. Because of this, it is necessary to achieve high precision (varying in microns) in miniature machining. If we want to guarantee machining high precision, it is necessary to analyse tool wear intensity in direct interaction with given machined materials. During long-term cutting process, different cutting wedge deformations occur, leading in most cases to a rapid wear and destruction of the cutting wedge. This article deal with experimental monitoring of tool wear intensity during miniature machining.
Numerical phase retrieval from beam intensity measurements in three planes
NASA Astrophysics Data System (ADS)
Bruel, Laurent
2003-05-01
A system and method have been developed at CEA to retrieve phase information from multiple intensity measurements along a laser beam. The device has been patented. Commonly used devices for beam measurement provide phase and intensity information separately or with a rather poor resolution whereas the MIROMA method provides both at the same time, allowing direct use of the results in numerical models. Usual phase retrieval algorithms use two intensity measurements, typically the image plane and the focal plane (Gerschberg-Saxton algorithm) related by a Fourier transform, or the image plane and a lightly defocus plane (D.L. Misell). The principal drawback of such iterative algorithms is their inability to provide unambiguous convergence in all situations. The algorithms can stagnate on bad solutions and the error between measured and calculated intensities remains unacceptable. If three planes rather than two are used, the data redundancy created confers to the method good convergence capability and noise immunity. It provides an excellent agreement between intensity determined from the retrieved phase data set in the image plane and intensity measurements in any diffraction plane. The method employed for MIROMA is inspired from GS algorithm, replacing Fourier transforms by a beam-propagating kernel with gradient search accelerating techniques and special care for phase branch cuts. A fast one dimensional algorithm provides an initial guess for the iterative algorithm. Applications of the algorithm on synthetic data find out the best reconstruction planes that have to be chosen. Robustness and sensibility are evaluated. Results on collimated and distorted laser beams are presented.
Theory of high-order harmonic generation for gapless graphene
NASA Astrophysics Data System (ADS)
Zurrón, Óscar; Picón, Antonio; Plaja, Luis
2018-05-01
We study the high-harmonic spectrum emitted by a single-layer graphene, irradiated by an ultrashort intense infrared laser pulse. We show the emergence of the typical non-perturbative spectral features, harmonic plateau and cut-off, for mid-infrared driving fields, at fluences below the damage threshold. In contrast to previous works, using THz drivings, we demonstrate that the harmonic cut-off frequency saturates with the intensity. Our results are derived from the numerical integration of the time-dependent Schrödinger equation using a nearest neighbor tight-binding description of graphene. We also develop a saddle-point analysis that reveals a mechanism for harmonic emission in graphene different from that reported in atoms, molecules and finite gap solids. In graphene, the first step is initiated by the non-diabatic crossing of the valence band electron trajectories through the Dirac points, instead of tunneling ionization/excitation. We include a complete identification of the trajectories contributing to any particular high harmonic and reproduce the harmonic cut-off scaling with the driving intensity.
Wedge cutting of mild steel by CO 2 laser and cut-quality assessment in relation to normal cutting
NASA Astrophysics Data System (ADS)
Yilbas, B. S.; Karatas, C.; Uslan, I.; Keles, O.; Usta, Y.; Yilbas, Z.; Ahsan, M.
2008-10-01
In some applications, laser cutting of wedge surfaces cannot be avoided in sheet metal processing and the quality of the end product defines the applicability of the laser-cutting process in such situations. In the present study, CO 2 laser cutting of the wedge surfaces as well as normal surfaces (normal to laser beam axis) is considered and the end product quality is assessed using the international standards for thermal cutting. The cut surfaces are examined by the optical microscopy and geometric features of the cut edges such as out of flatness and dross height are measured from the micrographs. A neural network is introduced to classify the striation patterns of the cut surfaces. It is found that the dross height and out of flatness are influenced significantly by the laser output power, particularly for wedge-cutting situation. Moreover, the cut quality improves at certain value of the laser power intensity.
Whyte, Enda F; Richter, Chris; O'connor, Siobhan; Moran, Kieran A
2018-04-01
We investigated the effects of high intensity, intermittent exercise (HIIP) and anticipation on trunk, pelvic and lower limb biomechanics during a crossover cutting manoeuvre. Twenty-eight male, varsity athletes performed crossover cutting manoeuvres in anticipated and unanticipated conditions pre- and post-HIIP. Kinematic and kinetic variables were captured using a motion analysis system. Statistical parametric mapping (repeated-measures ANOVA) was used to identify differences in biomechanical patterns. Results demonstrated that both unanticipation and fatigue (HIIP) altered the biomechanics of the crossover cutting manoeuvre, whereas no interactions effects were observed. Unanticipation resulted in less trunk and pelvic side flexion in the direction of cut (d = 0.70 - 0.79). This led to increased hip abductor and external rotator moments and increased knee extensor and valgus moments with small effects (d = 0.24-0.42), potentially increasing ACL strain. The HIIP resulted in trivial to small effects only with a decrease in internal knee rotator and extensor moment and decreased knee power absorption (d = 0.35), reducing potential ACL strain. The effect of trunk and hip control exercises in unanticipated conditions on the crossover cutting manoeuvre should be investigated with a view to refining ACL injury prevention programmes.
Wels, Michael; Carneiro, Gustavo; Aplas, Alexander; Huber, Martin; Hornegger, Joachim; Comaniciu, Dorin
2008-01-01
In this paper we present a fully automated approach to the segmentation of pediatric brain tumors in multi-spectral 3-D magnetic resonance images. It is a top-down segmentation approach based on a Markov random field (MRF) model that combines probabilistic boosting trees (PBT) and lower-level segmentation via graph cuts. The PBT algorithm provides a strong discriminative observation model that classifies tumor appearance while a spatial prior takes into account the pair-wise homogeneity in terms of classification labels and multi-spectral voxel intensities. The discriminative model relies not only on observed local intensities but also on surrounding context for detecting candidate regions for pathology. A mathematically sound formulation for integrating the two approaches into a unified statistical framework is given. The proposed method is applied to the challenging task of detection and delineation of pediatric brain tumors. This segmentation task is characterized by a high non-uniformity of both the pathology and the surrounding non-pathologic brain tissue. A quantitative evaluation illustrates the robustness of the proposed method. Despite dealing with more complicated cases of pediatric brain tumors the results obtained are mostly better than those reported for current state-of-the-art approaches to 3-D MR brain tumor segmentation in adult patients. The entire processing of one multi-spectral data set does not require any user interaction, and takes less time than previously proposed methods.
Efficient broadband near-infrared quantum cutting for solar cells.
Teng, Yu; Zhou, Jiajia; Liu, Xiaofeng; Ye, Song; Qiu, Jianrong
2010-04-26
Yb(2+) and Yb(3+) co-activated luminescent material that can cut one photon in ultraviolet and visible region into multi NIR photons could be used as a downconversion luminescent convertor in front of crystalline silicon solar cell panels to reduce thermalization loss of the solar cell. After a direct excitation of Yb(2+) ions, an intense Yb(3+) luminescence is observed based on a cooperative energy transfer process. The energy transfer process is discussed according to the dependence of Yb(3+) luminescence intensity on the excitation power and the ambient temperature.
Investigating bone chip formation in craniotomy.
Huiyu, He; Chengyong, Wang; Yue, Zhang; Yanbin, Zheng; Linlin, Xu; Guoneng, Xie; Danna, Zhao; Bin, Chen; Haoan, Chen
2017-10-01
In a craniotomy, the milling cutter is one of the most important cutting tools. The operating performance, tool durability and cutting damage to patients are influenced by the tool's sharpness, intensity and structure, whereas the cutting characteristics rely on interactions between the tool and the skull. In this study, an orthogonal cutting experiment during a craniotomy of fresh pig skulls was performed to investigate chip formation on the side cutting and face cutting of the skull using a high-speed camera. The cutting forces with different combinations of cutting parameters, such as the rake angle, clearance angle, depth of cut and cutting speed, were measured. The skull bone microstructure and cutting damage were observed by scanning electron microscope. Cutting models for different cutting approaches and various depths of cut were constructed and analyzed. The study demonstrated that the effects of shearing, tension and extrusion occur during chip formation. Various chip types, such as unit chips, splintering chips and continuous chips, were generated. Continuous pieces of chips, which are advisable for easy removal from the field of operation, were formed at greater depths of cut and tool rake angles greater than 10°. Cutting damage could be relieved with a faster recovery with clearance angles greater than 20°.
NASA Astrophysics Data System (ADS)
Saito, Hitoshi; Murakami, Wataru; Daimaru, Hiromu; Oguchi, Takashi
2017-01-01
Vegetation cover is an important factor for rainfall-induced landslides. We analyzed the effect of forest clear-cutting on the initiation of landslides using empirical rainfall intensity-duration (I-D) thresholds at Mt. Ichifusa, Japan, which is characterized by granitic rocks. Extensive clear-cutting was conducted for the forest industry during the late 1960s in the northern part of Mt. Ichifusa. This single episode of clear-cutting caused frequent shallow landslides triggered by rainfall. We interpreted orthorectified aerial photographs from 1969, 1976, 1980, 1985, 1990, 1995, 1999, and 2005 using GIS and mapped landslides based on these photographs. We then analyzed all rainfall events of the warm seasons (Apr.-Oct.) of 1952-2011 (60 years) based on hourly rain gauge data. We used basic rainfall parameters such as mean rainfall intensity (I, mm/h) and duration (D, h) and estimated the return periods of these rainfall conditions. We investigated rainfall I-D thresholds for landslide occurrences in each period represented by the aerial photographs and assessed the relationships between landslide occurrences and topographic characteristics from 10-m DEMs. The results show that several landslides occurred after clear-cutting before 1976 but that they have occurred most frequently during the periods 1976-1980, 1980-1985, and 1990-1995. Numerous landslides occurred in these years at steeper and gentler slopes in the clear-cut area, but few landslides occurred in the non-clear-cut area. Rainfall analysis demonstrates that rainfall I-D thresholds after clear-cutting declined to half of those of the non-clear-cut area. The return periods of these rainfall I-D thresholds also declined to 1 year for short durations of < 12 h and to < 3 years for 72 h in the clear-cut area. Our findings underscore the substantial hysteresis effects between clear-cutting and landslide occurrences at Mt. Ichifusa.
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.
Sabzehei, Faezeh; Kouhpayeh, Shirin; Dastjerdeh, Mansoureh Shahbazi; Khanahmad, Hossein; Salehi, Rasoul; Naderi, Shamsi; Taghizadeh, Razieh; Rabiei, Parisa; Hejazi, Zahra; Shariati, Laleh
2017-01-01
Gene editing technology has created a revolution in the field of genome editing. The three of the most famous tools in gene editing technology are zinc finger nucleases (ZFNs), transcription activator-like effector nucleases, clustered regularly interspaced short palindromic repeats (CRISPR), and CRISPR-associated systems. As their predictable nature, it is necessary to assess their efficiency. There are some methods for this purpose, but most of them are time labor and complicated. Here, we introduce a new prokaryotic reporter system, which makes it possible to evaluate the efficiency of gene editing tools faster, cheaper, and simpler than previous methods. At first, the target sites of a custom ZFN, which is designed against a segment of ampicillin resistance gene, were cloned on both sides of green fluorescent protein (GFP) gene to construct pPRO-GFP. Then pPRO-GFP was transformed into Escherichia coli TOP10F' that contains pZFN (contains expression cassette of a ZFN against ampicillin resistant gene), or p15A-KanaR as a negative control. The transformed bacteria were cultured on three separate media that contained ampicillin, kanamycin, and ampicillin + kanamycin; then the resulted colonies were assessed by flow cytometry. The results of flow cytometry showed a significant difference between the case (bacteria contain pZFN) and control (bacteria contain p15A, KanaR) in MFI (Mean Fluorescence Intensity) ( P < 0.0001). According to ZFN efficiency, it can bind and cut the target sites, the bilateral cutting can affect the intensity of GFP fluorescence. Our flow cytometry results showed that this ZFN could reduce the intensity of GFP color and colony count of bacteria in media containing amp + kana versus control sample.
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.
Rachel A. Tarpey; Martin F. Jurgensen; Brian J. Palik; Randy K. Kolka
2008-01-01
Periodic silvicultural thinnings (23.0, 27.6, 32.1 m2 ha-1 residual basal area) in a red pine stand growing on a sandy soil in north-central Minnesota over a 57-yr period increased soil compaction as the intensity of the thinning treatment increased. Of the three different methods used to measure soil compaction (bulk...
Educators Flock to NPS amidst Concerns about Budget Cuts
ERIC Educational Resources Information Center
Emeagwali, N. Susan
2011-01-01
At a time of intense politicking on Capitol Hill as legislators work feverishly to cut federal spending, and amidst more threats to slash Perkins funding, career and technical education (CTE) professionals from around the country converged on Washington, D.C., to attend the Association for Career and Technical Education's National Policy Seminar…
USDA-ARS?s Scientific Manuscript database
Twelve cacao (Theobroma cacao) clones propagated by grafting and orthotropic rooted cuttings of somatic embryo-derived plants were grown on an Ultisol soil at Corozal, Puerto Rico and evaluated for six years of production under intensive management. Year, variety, year x variety and propagation tre...
Nutrient losses from timber harvesting in a larch/ Douglas-fir forest
Nellie M. Stark
1979-01-01
Nutrient levels as a result of experimental clearcutting, shelterwood cutting, and group selection cutting - each with three levels of harvesting intensity - were studied in a larchfir forest in northwest Montana, experimentally logged with a skyline system. None of the treatments altered nutrient levels in an intermittent stream, nor were excessive amounts of...
Communicating Spending Cuts: Lessons for Australian University Leaders
ERIC Educational Resources Information Center
Sharrock, Geoff
2014-01-01
In 2011 and 2012, two Australian university vice chancellors flagged spending cuts at their institutions to overcome financial problems. In both cases, union and staff opposition led to public protests, intense media scrutiny, delays and retreats. This article compares the two cases to see what lessons may be drawn for university leaders faced…
Energy-Intensive Processes Portfolio: Addressing Key Energy Challenges Across U.S. Industry
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
AMO is developing advanced technologies that cut energy use and carbon emissions in some of the most energy-intensive processes within U.S. manufacturing. The brochure describes the AMO R&D projects that address these challenges.
Electrocautery effect on intestinal vascularisation in a murine model.
Tremblay, Jean-François; Sideris, Lucas; Leblond, François A; Trépanier, Jean-Sébastien; Badrudin, David; Drolet, Pierre; Mitchell, Andrew; Dubé, Pierre
2016-09-01
The use of electrocautery devices is associated with complications such as perforation or fistulisation when used near intestinal structures. This is likely due to its effect on vascularisation of the bowel wall. To test this hypothesis we established a murine model to quantify the effect of electrocautery injury on the intestinal microvascularisation. Sprague-Dawley rats were subjected to five electrocautery injuries on the small bowel in coagulation mode (30 W intensity) and in cut mode (40 W, 80 W and 200 W intensities) for durations of 1, 2 and 5 s. 5 mg/kg of fluorescein was injected intravenously, the injured bowel segments harvested and the rat sacrificed. The segments were analysed to measure the fluorescence of injured bowel compared to adjacent unharmed tissue. A significant decrease in bowel wall microvascularisation occurred with increasing intensity (coag 30 W/cut 40 W versus cut 200 W 1 s: p < 0.05) and duration of electrocautery injury (cut 40 W 1/2 s versus 5 s: p < 0.05). There was a 40% perforation rate when decreased bowel wall microvascularisation was 25% or more. Despite similar electrocautery injury, a significantly greater microvascularisation decrease was observed in jejunum compared to ileum (p < 0.05). We successfully established a murine model to quantify the decrease of bowel wall microvascularisation associated with electrocautery use. Unsurprisingly, the decrease in microvascularisation is greater with higher intensity and duration of electrocautery and is associated with more perforations in the experimental model. The jejunum seems more vulnerable to electrocautery injury than the ileum. These observations support caution when using electrocautery devices near intestinal structures.
NASA Astrophysics Data System (ADS)
Vinogradova, Julia; Perminova, Evgenia; Khabibullina, Fluza; Kovaleva, Vera; Lapteva, Elena
2016-04-01
Plant waste decomposition processes are closely associated with living activity of soil microbiota in aboveground ecosystems. Functional activity of microorganisms and soil invertebrates determines plant material transformation rate whereby changes in plant material chemical composition during destruction - succession change of soil biota. The purpose of the work was revealing the mechanism of microorganisms succession change during plant waste decomposition in middle-taiga green-moss spruce forests and coniferous-deciduous secondary stands formed after earlier cut bilberry spruce forests. The study materials were undisturbed bilberry spruce forest (Sample Plot 1 - SP1) and coniferous-deciduous secondary stands which were formed after tree cutting activities of 2001-2002 (SP2) and 1969 and 1970 (SP3). Plant material decomposition intensity was determined in microcosms isolated into kapron bags with cell size of 1 mm. At SP1 and SP2, test material was living mosses and at SP3 - fallen birch and aspen leaves. Every test material was exposed for 2 years. Destruction rate was calculated as a weight loss for a particular time period. Composition of micromycetes which participated in plant material decomposition was assessed by the method of inoculation of soil extract to Getchinson's medium and acidified Czapek's medium (pH=4.5). Microbe number and biomass was analyzed by the method of luminescent microscopy. Chemical analysis of plant material was done in the certified Ecoanalytical Laboratory of the Institute of Biology Komi SC UrD RAS. Finally, plant material destruction intensity was similar for study plots and comprised 40-44 % weight loss for 2 years. The strongest differences in plant material decomposition rate between undisturbed spruce forests and secondary after-cut stands were observed at first stages of destruction process. In the first exposition year, mineralizing processes were most active in undisturbed spruce forest. Decomposition rate in cuts at that period was less by a factor of 1.7-2.3. The highest diversity of moss-decomposing micromycetes (30 species of microscopic fungi of 13 genera) was found for undisturbed spruce forest (SP1). At cuts, the figures were 17 and 23 species of micromycetes, correspondingly. Succession change in composition of micromycetes was best pronounced in undisturbed spruce forest. At cuts, there was no clear mechanism of micromycetes species diversity change during plant waste decomposition. This could serve an anthropogenic disturbance marker of taiga ecosystems. Generally, microscopic moss- and leaf-decomposing fungi at all plots were very species specific. Total biomass of microorganisms in microcosms at cuts was less than that at undisturbed spruce forest by 1.4-1.6 time. Its structure was dominated by mycelium and fungal spores (98-99 % total biomass). On leaf waste decomposition (SP3), microbe biomass got more bacteria. By the obtained data, undisturbed middle-taiga spruce forests have better conditions for living activity of plant waste-decomposing microscopic fungi. This is evidenced by less species diversity of microscopic fungi, shorter length and less biomass of mycelium at cuts as compared with undisturbed spruce forests.
Whyte, Enda F; Richter, Chris; OʼConnor, Siobhan; Moran, Kieran A
2018-06-01
Whyte, EF, Richter, C, O'Connor, S, and Moran, KA. Investigation of the effects of high-intensity, intermittent exercise and unanticipation on trunk and lower limb biomechanics during a side-cutting maneuver using statistical parametric mapping. J Strength Cond Res 32(6): 1583-1593, 2018-Anterior cruciate ligament (ACL) injuries frequently occur during side-cutting maneuvers when fatigued or reacting to the sporting environment. Trunk and hip biomechanics are proposed to influence ACL loading during these activities. However, the effects of fatigue and unanticipation on the biomechanics of the kinetic chain may be limited by traditional discrete point analysis. We recruited 28 male, varsity, Gaelic footballers (21.7 ± 2.2 years; 178.7 ± 14.6 m; 81.8 ± 11.4 kg) to perform anticipated and unanticipated side-cutting maneuvers before and after a high-intensity, intermittent exercise protocol (HIIP). Statistical parametric mapping (repeated-measures analysis of varience) identified differences in phases of trunk and stance leg biomechanics during weight acceptance. Unanticipation resulted in less trunk flexion (p < 0.001) and greater side flexion away from the direction of cut (p < 0.001). This led to smaller (internal) knee flexor and greater (internal) knee extensor (p = 0.002-0.007), hip adductor (p = 0.005), and hip external rotator (p = 0.007) moments. The HIIP resulted in increased trunk flexion (p < 0.001) and side flexion away from the direction of cut (p = 0.038), resulting in smaller (internal) knee extensor moments (p = 0.006). One interaction effect was noted demonstrating greater hip extensor moments in the unanticipated condition post-HIIP (p = 0.025). Results demonstrate that unanticipation resulted in trunk kinematics considered an ACL injury risk factor. A subsequent increase in frontal and transverse plane hip loading and sagittal plane knee loading was observed, which may increase ACL strain. Conversely, HIIP-induced trunk kinematic alterations resulted in reduced sagittal plane knee and subsequent ACL loading. Therefore, adequate hip and knee control is important during unanticipated side-cutting maneuvers.
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.
Long-term management impacts on carbon storage in Lake States forests
Matthew Powers; Randall Kolka; Brian Palik; Rachel McDonald; Martin Jurgensen
2011-01-01
We examined carbon storage following 50+ years of forest management in two long-term silvicultural studies in red pine and northern hardwood ecosystems of North Americaâs Great Lakes region. The studies contrasted various thinning intensities (red pine) or selection cuttings, shelterwoods, and diameter-limit cuttings (northern hardwoods) to unmanaged controls of...
An Assessment of Soil Disturbance from Five Harvesting Intensities
John Klepac; Stephen E. Reutebuch; Robert B. Rummer
1999-01-01
Surface soil disturbance was compared among a commercial thinning, group selection, patch cut, 2-age, and clearcut. The thinning, group selection and patch cut units had significantly higher percentages of undisturbed area. The 2-age unit had a significantly higher percentage of area disturbed with litter in place. The clearcut unit had a significantly higher...
Beef customer satisfaction: trained sensory panel ratings and Warner-Bratzler shear force values.
Lorenzen, C L; Miller, R K; Taylors, J F; Neely, T R; Tatum, J D; Wise, J W; Buyek, M J; Reagan, J O; Savell, J W
2003-01-01
Trained sensory panel ratings and Warner-Bratzler shear force (WBS) values from the Beef Customer Satisfaction study are reported. Carcasses were chosen to fit into USDA quality grades of Top Choice (upper two-thirds of USDA Choice), Low Choice, High Select, and Low Select. A trained, descriptive attribute panel evaluated top loin, top sirloin, and top round steaks for muscle fiber tenderness, connective tissue amount, overall tenderness, juiciness, flavor intensity, cooked beef flavor intensity, and cooked beef fat flavor intensity. Four steaks from each of the three cuts from each carcass were assigned randomly to one of four cooking endpoint temperature treatments (60, 65, 70, or 75 degrees C) for WBS determination. For all trained panel measures of tenderness and WBS, regardless of USDA quality grade, top loin steaks were rated higher than top sirloin steaks, which were rated higher than top round steaks (P < 0.05). There were significant interactions between USDA quality grade and cut for most of the trained sensory panel traits: USDA quality grade influenced ratings for top loin steaks more than ratings for top round steaks or top sirloin steaks. Three interactions were significant for WBS values: USDA quality grade x endpoint temperature (P = 0.02), USDA quality grade x cut (P = 0.0007), and cut x endpoint temperature (P = 0.0001). With the exception of High Select, WBS values increased (P < 0.05) for each grade with increasing endpoint temperature. Choice top loin and top round steaks had lower (P < 0.05) WBS values than Select steaks of the same cut; however, only Top Choice top sirloin steaks differed (P < 0.05) from the other USDA grades. As endpoint temperatures increased, WBS values for top sirloin steaks increased substantially compared to the other cuts. When cooked to 60 degrees C, top sirloin steaks were closer to top loin steaks in WBS values, when cooked to 75 degrees C, top sirloin steaks were closer to top round steaks in WBS values. Simple correlation coefficients between consumer ratings and trained sensory muscle fiber tenderness, connective tissue amount, overall tenderness, juiciness, flavor intensity, and cooked beef fat flavor were significant (P < 0.05), but values were low. While relationships exist between consumer and trained sensory measures, it is difficult to predict from objective data how consumers will rate meat at home.
Comprehensive surface treatment of high-speed steel tool
NASA Astrophysics Data System (ADS)
Fedorov, Sergey V.; Aleshin, Sergey V.; Swe, Min Htet; Abdirova, Raushan D.; Kapitanov, Alexey V.; Egorov, Sergey B.
2018-03-01
One of the promising directions of hardening of high-speed steel tool is the creation on their surface of the layered structures with the gradient of physic-chemical properties between the wear-resistant coatings to the base material. Among the methods of such surface modification, a special process takes place based on the use of pulsed high-intensity charged particle beams. The high speed of heating and cooling allows structural-phase transformations in the surface layer, which cannot be realized in a stationary mode. The treatment was conducted in a RITM-SP unit, which constitutes a combination of a source of low-energy high-current electron beams "RITM" and two magnetron spraying systems on a single vacuum chamber. The unit enables deposition of films on the surface of the desired product and subsequent liquid-phase mixing of materials of the film and the substrate by an intense pulse electron beam. The article discusses features of the structure of the subsurface layer of high-speed steel M2, modified by surface alloying of a low-energy high-current electron beam, and its effect on the wear resistance of the tool when dry cutting hard to machine Nickel alloy. A significant decrease of intensity of wear of high-speed steel with combined treatment happens due to the displacement of the zone of wear and decrease the radius of rounding of the cutting edge because of changes in conditions of interaction with the material being treated.
NASA Astrophysics Data System (ADS)
Ivanova, T. N.; Lyupa, D. C.; Revenko, N. F.; Berkutova, T. A.; Silivanova, O. A.
2018-03-01
A lot of factors varied in time lead to instability of the grinding process. Besides, the method of grinding influences significantly the productivity and quality of processing. In this regard a creation of processes of intensive defect-free grinding on the basis of new constructive and technology solutions represents the scientific problem which is of great importance. One of such solutions is application of planetary face grinding which allows simultaneously changing the kinematics of movement, implementing discontinuous grinding. The distinctive features of such grinding are decreasing the heat release rate in a contact zone; ensuring intermittence of the process with a solid grinding wheel; reverse grinding; cutting by different edges of an abrasive grain; stabilization of working parameters of a grinding wheel; ensuring work of a grinding wheel in a self-sharpening mode. The design of the planetary grinding tool was developed for plane surface processing for implementation of the specified distinctive features of planetary grinding. The kinematics of shaping a surface by flat face diamond grinding has been investigated; manufacturing capabilities of planetary face grinding have been revealed, and ways of improvement of quality and productivity have been offered. The algorithm and the program to define the motion path of a grain depending on the given set of grinding factors were received. Optimization of the process of face diamond grinding using the planetary grinding device has been confirmed with the developed program and techniques to choose cutting conditions of planetary grinding and characteristics of grinding wheels for processing different materials. While studying the process of planetary grinding, special attention was paid to the research how processing conditions influence microgeometry of the processed surface made of steel 4X5M (Russian State Standard (GOST)). As a result of the executed research, it was established that surface roughness parameter Ra during the processing using the planetary grinding device is 35 - 40% less than when using the tool with the solid cutting surface. This phenomenon can be accounted for more uniform work of the cutting grains of the planetary grinding tool as the number of meetings of diamond grains with the surface being processed increases. At the same time, it should be noted that during the planetary grinding more intensive smoothing of tops of microroughnesses is observed that provides the creation of steadier cutting shape. The given method of calculation of cost value of grinding operation allows solving various manufacturing problems: to compare cost value of grinding different materials, grinding wheels of different parameters; to define the optimum grinding conditions.
Method of sections in analytical calculations of pneumatic tires
NASA Astrophysics Data System (ADS)
Tarasov, V. N.; Boyarkina, I. V.
2018-01-01
Analytical calculations in the pneumatic tire theory are more preferable in comparison with experimental methods. The method of section of a pneumatic tire shell allows to obtain equations of intensities of internal forces in carcass elements and bead rings. Analytical dependencies of intensity of distributed forces have been obtained in tire equator points, on side walls (poles) and pneumatic tire bead rings. Along with planes in the capacity of secant surfaces cylindrical surfaces are used for the first time together with secant planes. The tire capacity equation has been obtained using the method of section, by means of which a contact body is cut off from the tire carcass along the contact perimeter by the surface which is normal to the bearing surface. It has been established that the Laplace equation for the solution of tasks of this class of pneumatic tires contains two unknown values that requires the generation of additional equations. The developed computational schemes of pneumatic tire sections and new equations allow to accelerate the pneumatic tire structure improvement process during engineering.
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.
A difference-matrix metaheuristic for intensity map segmentation in step-and-shoot IMRT delivery.
Gunawardena, Athula D A; D'Souza, Warren D; Goadrich, Laura D; Meyer, Robert R; Sorensen, Kelly J; Naqvi, Shahid A; Shi, Leyuan
2006-05-21
At an intermediate stage of radiation treatment planning for IMRT, most commercial treatment planning systems for IMRT generate intensity maps that describe the grid of beamlet intensities for each beam angle. Intensity map segmentation of the matrix of individual beamlet intensities into a set of MLC apertures and corresponding intensities is then required in order to produce an actual radiation delivery plan for clinical use. Mathematically, this is a very difficult combinatorial optimization problem, especially when mechanical limitations of the MLC lead to many constraints on aperture shape, and setup times for apertures make the number of apertures an important factor in overall treatment time. We have developed, implemented and tested on clinical cases a metaheuristic (that is, a method that provides a framework to guide the repeated application of another heuristic) that efficiently generates very high-quality (low aperture number) segmentations. Our computational results demonstrate that the number of beam apertures and monitor units in the treatment plans resulting from our approach is significantly smaller than the corresponding values for treatment plans generated by the heuristics embedded in a widely use commercial system. We also contrast the excellent results of our fast and robust metaheuristic with results from an 'exact' method, branch-and-cut, which attempts to construct optimal solutions, but, within clinically acceptable time limits, generally fails to produce good solutions, especially for intensity maps with more than five intensity levels. Finally, we show that in no instance is there a clinically significant change of quality associated with our more efficient plans.
Snag density varies with intensity of timber harvest and human access
Michael J. Wisdom; Lisa J. Bate
2008-01-01
Many species of vertebrates depend on snags (standing dead trees) for persistence, and limited research suggests that snag density is lower in areas of intensive timber harvest and increased human access. While intensive timber harvest is one source of potential snag loss, ease of human access to forest stands may also facilitate loss via firewood cutting of snags....
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, D.; Krasheninnikov, S. I.; Luan, S. X.
The generation of super-high energetic electrons influenced by pre-plasma in relativistic intensity laser–matter interaction is studied in a one-dimensional slab approximation with particle-in-cell simulations. Different pre-plasma scale lengths and laser intensities are considered, showing an increase in both particle number and cut-off kinetic energy of electrons with the increase of pre-plasma scale length and laser intensity, the cut-off kinetic energy greatly exceeding the corresponding laser ponderomotive energy. A two-stage electron acceleration model is proposed to explain the underlying physics. The first stage is attributed to the synergetic acceleration by longitudinal electric field and counter-propagating laser pulses, and a scaling lawmore » is obtained with efficiency depending on the pre-plasma scale length and laser intensity. These electrons pre-accelerated in the first stage could build up an intense electrostatic potential barrier with maximal value several times as large as the initial electron kinetic energy. Some of the energetic electrons could be further accelerated by reflection off the electrostatic potential barrier, with their finial kinetic energies significantly higher than the values pre-accelerated in the first stage.« less
Wu, D.; Krasheninnikov, S. I.; Luan, S. X.; ...
2016-10-03
The generation of super-high energetic electrons influenced by pre-plasma in relativistic intensity laser–matter interaction is studied in a one-dimensional slab approximation with particle-in-cell simulations. Different pre-plasma scale lengths and laser intensities are considered, showing an increase in both particle number and cut-off kinetic energy of electrons with the increase of pre-plasma scale length and laser intensity, the cut-off kinetic energy greatly exceeding the corresponding laser ponderomotive energy. A two-stage electron acceleration model is proposed to explain the underlying physics. The first stage is attributed to the synergetic acceleration by longitudinal electric field and counter-propagating laser pulses, and a scaling lawmore » is obtained with efficiency depending on the pre-plasma scale length and laser intensity. These electrons pre-accelerated in the first stage could build up an intense electrostatic potential barrier with maximal value several times as large as the initial electron kinetic energy. Some of the energetic electrons could be further accelerated by reflection off the electrostatic potential barrier, with their finial kinetic energies significantly higher than the values pre-accelerated in the first stage.« less
NASA Astrophysics Data System (ADS)
Zaal, K. J. J. M.
1991-06-01
In programming solutions of complex function theory, the complex logarithm function is replaced by the complex logarithmic function, introducing a discontinuity along the branch cut into the programmed solution which was not present in the mathematical solution. Recently, Liaw and Kamel presented their solution of the infinite anisotropic centrally cracked plate loaded by an arbitrary point force, which they used as Green's function in a boundary element method intended to evaluate the stress intensity factor at the tip of a crack originating from an elliptical home. Their solution may be used as Green's function of many more numerical methods involving anisotropic elasticity. In programming applications of Liaw and Kamel's solution, the standard definition of the logarithmic function with the branch cut at the nonpositive real axis cannot provide a reliable computation of the displacement field for Liaw and Kamel's solution. Either the branch cut should be redefined outside the domain of the logarithmic function, after proving that the domain is limited to a part of the plane, or the logarithmic function should be defined on its Riemann surface. A two dimensional line fractal can provide the link between all mesh points on the plane essential to evaluate the logarithm function on its Riemann surface. As an example, a two dimensional line fractal is defined for a mesh once used by Erdogan and Arin.
Wu, Shibin; Zhuang, Ling; Wei, Xinhua; Sak, Mark; Neb, Duric; Hu, Jiani; Xie, Yaoqin
2017-01-01
As an emerging modality for whole breast imaging, ultrasound tomography (UST), has been adopted for diagnostic purposes. Efficient segmentation of an entire breast in UST images plays an important role in quantitative tissue analysis and cancer diagnosis, while major existing methods suffer from considerable time consumption and intensive user interaction. This paper explores three-dimensional GrabCut (GC3D) for breast isolation in thirty reflection (B-mode) UST volumetric images. The algorithm can be conveniently initialized by localizing points to form a polygon, which covers the potential breast region. Moreover, two other variations of GrabCut and an active contour method were compared. Algorithm performance was evaluated from volume overlap ratios (TO, target overlap; MO, mean overlap; FP, false positive; FN, false negative) and time consumption. Experimental results indicate that GC3D considerably reduced the work load and achieved good performance (TO = 0.84; MO = 0.91; FP = 0.006; FN = 0.16) within an average of 1.2 min per volume. Furthermore, GC3D is not only user friendly, but also robust to various inputs, suggesting its great potential to facilitate clinical applications during whole-breast UST imaging. In the near future, the implemented GC3D can be easily automated to tackle B-mode UST volumetric images acquired from the updated imaging system. PMID:28786946
Investigation of Cutting Quality of Remote DOE Laser Cutting in 0.5 mm Stainless Steel
NASA Astrophysics Data System (ADS)
Villumsen, Sigurd Lazic; Kristiansen, Morten
It has previously been shown that the stability of the remote fusion cutting (RFC) process can be increased by modifying the intensity profile of the laser by means of a diffractive optical element (DOE). This paper investigates the quality of remote DOE cutting (RDC) conducted with a 3 kW single mode fiber laser in 0.5 mm stainless steel. An automatic measurement system is used to investigate how the travel speed, focus offset and angle of incidence effect the kerf width and kerf variance. The study shows that the RDC process has a very low kerf width variance, and that the kerf width decreases with cutting speed. Furthermore, selected etched samples show a significant increase in the perpendicularity of the cuts when compared to RFC. Also, on average, the depth of the layer of molten material for RFC is 83% deeper than for RDC.
Forest cutting and impacts on carbon in the eastern United States
Zhou, Decheng; Liu, Shuguang; Oeding, Jennifer; Zhao, Shuqing
2013-01-01
Forest cutting is a major anthropogenic disturbance that affects forest carbon (C) storage and fluxes. Yet its characteristics and impacts on C cycling are poorly understood over large areas. Using recent annualized forest inventory data, we estimated cutting-related loss of live biomass in the eastern United States was 168 Tg C yr−1 from 2002 to 2010 (with C loss per unit forest area of 1.07 Mg ha−1 yr−1), which is equivalent to 70% of the total U.S. forest C sink or 11% of the national annual CO2 emissions from fossil-fuel combustion over the same period. We further revealed that specific cutting-related C loss varied with cutting intensities, forest types, stand ages, and geographic locations. Our results provide new insights to the characteristics of forest harvesting activities in the eastern United States and highlight the significance of partial cutting to regional and national carbon budgets.
NFC-enabled, tattoo-like stretchable biosensor manufactured by "cut-and-paste" method.
Hyoyoung Jeong; Taewoo Ha; Kuang, Irene; Linxiao Shen; Zhaohe Dai; Nan Sun; Nanshu Lu
2017-07-01
The wearables industry is lacking in devices that have the ability to provide valuable biometrics data in a soft, wireless and disposable system. Such a system should be high performance, multifunctional, but battery-free and low cost. Near field communication (NFC) is a wireless communication protocol built in many smartphones nowadays that can read data from battery-free passive tags. As a result, NFC-enabled wearable biosensors have been reported, but they are either unstretchable or have to be manufactured by labor- and time-intensive photolithography and transfer-printing processes. Using a dry and freeform "cut-and-paste" method, we have built a wireless and low-cost stretchable biosensor that integrates temperature sensor, light source/sensor, NFC chip, and antenna. It is battery-free and can be laminated on any part of human skin like a temporary transfer tattoo. The sensor can fully follow the stretching and compression of skin without mechanical failure or delamination. Thus, it is imperceptible to wear and can perform high-fidelity sensing. Potential applications include, but are not limited to, skin thermography and photometry.
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...
Status of Prvately Owned Harvested Timberland in East Texas, 1975-1986
William H. McWilliams; David J. Skove
1987-01-01
Harvesting was conducted on 4.7 million acres, or 43 percent of the privately owned timberland, in east Texas between 1975 and 1986. Cutting was most intensive on forest industry lands, where 59 percent of the total timberland base underwent some form of harvesting. Seventy-nine percent of the pine and mixed pinehardwood stands receiving heavy cutting exhibited an...
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...
NASA Astrophysics Data System (ADS)
Dorman, L. I.; Iucci, N.; Pustil'Nik, L. A.; Sternlieb, A.; Villoresi, G.; Zukerman, I. G.
On the basis of cosmic ray hourly data obtained by NM of Emilio Segre' Observatory (hight 2025 m above s.l., cut-off rigidity for vertical direction 10.8 GV) we determine the snow effect in CR for total neutron intensity and for multiplicities m=1, m=2, m=3, m=4, m=5, m=6, and m=7. For comparison and excluding primary CR variations we use also hourly data on neutron multiplicities obtained by Rome NM (about sea level, cut-off rigidity 6.7 GV). In this paper we will analize effects of snow in periods from 4 January 2000 to 15 April 2000 with maximal absorption effect about 5%, and from 21 December 2000 up to 31 March 2001 with maximal effect 13% in the total neu- tron intensity. We use the periods without snow to determine regeression coefficients between primary CR variations observed by NM of Emilio Segre' Observatory, and by Rome NM. On the basis of obtained results we develop a method to correct data on snow effect by using several NM hourly data. On the basis of our data we estimate the accuracy with what can be made correction of NM data of stations where the snow effect can be important.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marler, R.L.
1981-11-01
Intensive cultivation of fast-growing hardwoods, such as hybrid poplars, is a promising method of assuring adequate supplies of biomass for energy purposes. This report details the establishment of a hybrid poplar nursery on formerly unused land at the Reynolds Metals Company's reduction plant in Massena, NY and presents the results obtained during the first growing season. Cuttings from the nursery replanted during the Spring of 1982 are the first phase of a 600-acre hybrid poplar plantation at the Reynolds site.
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
NASA Astrophysics Data System (ADS)
Ammann, C.; Leifeld, J.; Neftel, A.; Fuhrer, J.
2012-04-01
Experimental assessment of soil carbon (C) stock changes over time is typically based on the application of either one of two methods, namely (i) repeated soil inventory and (ii) determination of the ecosystem C budget or net biome productivity (NBP) by continuous measurement of CO2 exchange in combination with quantification of other C imports and exports. However, there exist hardly any published study hitherto that directly compared the results of both methods. Here, we applied both methods in parallel to determine C stock changes of two temperate grassland fields previously converted from long-term cropland. The grasslands differed in management intensity with either intensive management (high fertilization, frequent cutting) or extensive management (no fertilization, less frequent cutting). Soil organic C stocks (0-45 cm depth) were quantified at the beginning (2001) and the end (2006) of a 5 year observational period using the equivalent soil mass approach. For the same period and in both fields, NBP was quantified from net CO2 fluxes monitored using eddy covariance systems, and measured C import by organic fertilizer and C export by harvest. Both NBP and repeated soil inventories revealed a consistent and significant difference between management systems of 170 ± 48 and 253 ± 182 g C m-2 a-1, respectively. For both fields, the inventory method showed a tendency towards higher C loss/smaller C gain than NBP. In the extensive field, a significant C loss was observed by the inventory but not by the NBP approach. Thus both, flux measurements and repeated soil sampling, seem to be adequate and equally suited for detecting relative management effects. However, the suitability for tracking absolute changes in SOC could not be proven for neither of the two methods. Overall, our findings stress the need for more direct comparisons to evaluate whether the observed difference in the outcome of the two approaches reflects a general methodological bias, which would have important implications for regional terrestrial C budgets.
NASA Astrophysics Data System (ADS)
Kubin, Eero
2013-04-01
Clear-cutting and site preparation cause the greatest changes in site conditions and to the environment. The oldest research carried out within the boreal coniferous forest zone on the leaching of nutrients into watercourses was conducted in Sweden in the early 1970s. Also in Finland, the effect of clear-cutting and site preparation on the quality of surface runoff has been monitored since 1974 and into the groundwater, after waste wood harvesting, since 1986. Recently intensive biomass harvest has been rapidly increasing and nowadays about seven percent of the total consumption of energy in Finland comes from forest energy. The consumption derived from wood-based fuels is as much as 23 per cent of the total energy. Thus study and understanding forest ecosystems function is nowadays facing new challenges, especially when harvested forest energy, especially stumps, course disturbances and more water penetrating into the soil and groundwater in addition to other ecosystem changes. According the long term-monitoring results nitrate nitrogen seems to be the foremost nutrient leached into the groundwater as a consequence of forestry operations. The effects of clear-cutting on nitrate nitrogen leaching and concentrations in surface water have been shown to last only a few years, but the long-term property of increasing groundwater concentrations, have persisted 25 years which has not reported earlier from other sites. Clear-cutting increases the input of precipitation, but in northern areas this cannot be the main reason for the higher values. The greater part of the increased concentrations is due to the decomposition of cutting waste and humus. This is interesting in relation to intensive biomass harvesting. The availability and the quality of water are strongly influenced by forests. The relationship between forests and water is therefore a critical issue that must be accorded high priority also when developing forest biomass harvesting for energy. To develop best forest management practices to protect water quality is becoming more and more important. Forests are stabilizing soils and protecting watersheds. In the conference the long-term effects of different regeneration cuttings and biomass harvesting to the ground water will be discussed with special attention to the needs of understanding the great value of catchment base monitoring.
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.
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.
NASA Astrophysics Data System (ADS)
Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Salewski, Mirko; Leipold, Frank; Kusano, Yukihiro
2014-07-01
We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV emission of the gliding arc were investigated by optical methods. High-speed photography was utilized to reveal flow-rate dependent dynamics such as ignitions, propagation, short-cutting events, extinctions and conversions of the discharge from glowtype to spark-type. Short-cutting events and ignitions occur more frequently at higher flow rates. The anchor points of the gliding arc are mostly steady at the top of the electrodes at lower flow rates whereas at higher flow rates they glide up along the electrodes most of the time. The afterglow of fully developed gliding arcs is observed to decay over hundreds of microseconds after being electronically short-cut by a newly ignited arc. The extinction time decreases with the increase of the flow rate. The frequency of the conversion of a discharge from glow-type to spark-type increases with the flow rate. Additionally, spatial distributions of ground-state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy and it is found that the emission intensity of NO γ (A-X), OH (A-X) and N2 (C-B) increase with the flow rates showing more characteristics of spark-type arcs. The observed phenomena indicate the significance of the interaction between local turbulence and the gliding arc.
Effective plasmonic mode-size converter.
Park, Hae-Ryeong; Park, Jong-Moon; Kim, Min-su; Ju, Jung Jin; Son, Jung-Han; Lee, Myung-Hyun
2011-10-24
Plasmonic mode-size converters (PMSCs) for long-range surface plasmon polaritons (LR-SPPs) at the wavelength of 1.55 μm are presented. The PMSC is composed of an insulator-metal-insulator waveguide (IMI-W), a laterally tapered insulator-metal-insulator-metal-insulator waveguide (LT-IMIMI-W), and an IMIMI-W in series. The mode-intensity sizes of the LR-SPPs for the IMI-W and the IMIMI-W were not only calculated using a finite element method but were also experimentally measured. The propagation losses of the IMI-W and the IMIMI-W as well as the coupling losses between them were analyzed by the cut-back method to investigate the effect of LT-IMIMI-Ws. By using the PMSC with a ~27 ° angled LT-IMIMI-W, the coupling loss between a polarization-maintaining fiber and a 3 μm-wide IMIMI-W was reduced by ~3.4 dB. Moreover, the resulting mode-intensity in the output of the PMSC was squeezed to ~35% of the mode-intensity in the input IMI-W. The PMSC may be potentially useful for bridging micro- to nano-plasmonic integrated circuits. © 2011 Optical Society of America
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.
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
Prognosis for Survival of Young Women with Breast Cancer by Quantitative p53 Immunohistochemistry
Axelrod, David E.; Shah, Kinsuk; Yang, Qifeng; Haffty, Bruce G.
2015-01-01
p53 protein detected immunohistochemically has not been accepted as a biomarker for breast cancer patients because of disparate reports of the relationship between the amount of p53 protein detected and patient survival. The purpose of this study was to determine experimental conditions and methods of data analysis for which p53 stain intensity could be prognostic for survival of young breast cancer patients. A tissue microarray of specimens from 93 patients was stained with anti-p53 antibody, and stain intensity measured with a computer-aided image analysis system. A cut-point at one standard deviation below the mean of the distribution of p53 stain intensity separated patients into two groups with significantly different survival. These results were confirmed by Quantitative Nuclear Grade determined by DNA-specific Feulgen staining. P53 provided information beyond ER and PR status. Therefore, under the conditions reported here, p53 protein can be an effective prognostic factor for young breast cancer patients. PMID:26322145
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...
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.
NASA Astrophysics Data System (ADS)
Cheluszka, Piotr
2017-12-01
This article discusses the issue of selecting a pick system for cutting mining machinery, concerning the reduction of vibrations in the cutting system, particularly in a load-carrying structure at work. Numerical analysis was performed on a telescopic roadheader boom equipped with transverse heads. A frequency range of the boom's free vibrations with a set structure and dynamic properties were determined based on a dynamic model. The main components excited by boom vibrations, generated through the process of cutting rock, were identified. This was closely associated with the stereometry of the cutting heads. The impact on the pick system (the number of picks and their arrangement along the side of the cutting head) was determined by the intensity of the external boom load elements, especially in resonance zones. In terms of the anti-resonance criterion, an advantageous system of cutting head picks was determined as a result of the analysis undertaken. The correct selection of the pick system was ascertained based on a computer simulation of the dynamic loads and vibrations of a roadheader telescopic boom.
NASA Astrophysics Data System (ADS)
Ali, H.; Yilbas, B. S.
2016-09-01
Phonon cross-plane transport across silicon and diamond thin films pair is considered, and thermal boundary resistance across the films pair interface is examined incorporating the cut-off mismatch and diffusive mismatch models. In the cut-off mismatch model, phonon frequency mismatch for each acoustic branch is incorporated across the interface of the silicon and diamond films pair in line with the dispersion relations of both films. The frequency-dependent and transient solution of the Boltzmann transport equation is presented, and the equilibrium phonon intensity ratios at the silicon and diamond film edges are predicted across the interface for each phonon acoustic branch. Temperature disturbance across the edges of the films pair is incorporated to assess the phonon transport characteristics due to cut-off and diffusive mismatch models across the interface. The effect of heat source size, which is allocated at high-temperature (301 K) edge of the silicon film, on the phonon transport characteristics at the films pair interface is also investigated. It is found that cut-off mismatch model predicts higher values of the thermal boundary resistance across the films pair interface as compared to that of the diffusive mismatch model. The ratio of equilibrium phonon intensity due to the cut-off mismatch over the diffusive mismatch models remains >1 at the silicon edge, while it becomes <1 at the diamond edge for all acoustic branches.
ERIC Educational Resources Information Center
Loprinzi, Paul D.; Lee, Hyo; Cardinal, Bradley J.; Crespo, Carlos J.; Andersen, Ross E.; Smit, Ellen
2012-01-01
The purpose of this study was to examine the influence of child and adult cut-points on physical activity (PA) intensity, the prevalence of meeting PA guidelines, and association with selected health outcomes. Participants (6,578 adults greater than or equal to 18 years, and 3,174 children and adolescents less than or equal to 17 years) from the…
ERIC Educational Resources Information Center
Howe, Christopher C. F.; Moir, Hannah J.; Easton, Chris
2017-01-01
This study establishes tri-axial activity count (AC) cut-points for the GT3X+ accelerometer to classify physical activity intensity in overweight and obese adults. Further, we examined the accuracy of established and novel energy expenditure (EE) prediction equations based on AC and other metrics. "Part 1": Twenty overweight or obese…
Park, Hyun; Yoon, Sang-Wook; Sokolov, Amit
2015-12-01
Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a non-invasive method to treat uterine fibroids. To help determine the patient suitability for MRgFUS, we propose a new objective measure: the scaled signal intensity (SSI) of uterine fibroids in T2 weighted MR images (T2WI). Forty three uterine fibroids in 40 premenopausal women were included in this retrospective study. SSI of each fibroid was measured from the screening T2WI by standardizing its mean signal intensity to a 0-100 scale, using reference intensities of rectus abdominis muscle (0) and subcutaneous fat (100). Correlation between the SSI and the non-perfused volume (NPV) ratio (a measure for treatment success) was calculated. Pre-treatment SSI showed a significant inverse-correlation with post treatment NPV ratio (p < 0.05). When dichotomizing NPV ratio at 45 %, the optimal cut off value of the SSI was found to be 16.0. A fibroid with SSI value 16.0 or less can be expected to have optimal responses. The SSI of uterine fibroids in T2WI can be suggested as an objective parameter to help in patient selection for MRgFUS. • Signal intensity of fibroid in MR images predicts treatment response to MRgFUS. • Signal intensity is standardized into scaled form using adjacent tissues as references. • Fibroids with SSI less than 16.0 are expected to have optimal responses.
Functional diversity, succession, and human-mediated disturbances in raised bog vegetation.
Dyderski, Marcin K; Czapiewska, Natalia; Zajdler, Mateusz; Tyborski, Jarosław; Jagodziński, Andrzej M
2016-08-15
Raised and transitional bogs are one of the most threatened types of ecosystem, due to high specialisation of biota, associated with adaptations to severe environmental conditions. The aim of the study was to characterize the relationships between functional diversity (reflecting ecosystem-shaping processes) of raised bog plant communities and successional gradients (expressed as tree dimensions) and to show how impacts of former clear cuts may alter these relationships in two raised bogs in 'Bory Tucholskie' National Park (N Poland). Herbaceous layers of the plant communities were examined by floristic relevés (25m(2)) on systematically established transects. We also assessed patterns of tree ring widths. There were no relationships between vegetation functional diversity components and successional progress: only functional dispersion was negatively, but weakly, correlated with median DBH. Lack of these relationships may be connected with lack of prevalence of habitat filtering and low level of competition over all the successional phases. Former clear cuts, indicated by peaks of tree ring width, influenced the growth of trees in the bogs studied. In the bog with more intensive clear cuts we found more species with higher trophic requirements, which may indicate nutrient influx. However, we did not observe differences in vegetation patterns, functional traits or functional diversity indices between the two bogs studied. We also did not find an influence of clear cut intensity on relationships between functional diversity indices and successional progress. Thus, we found that alteration of the ecosystems studied by neighbourhood clear cuts did not affect the bogs strongly, as the vegetation was resilient to these impacts. Knowledge of vegetation resilience after clear cuts may be crucial for conservation planning in raised bog ecosystems. Copyright © 2016 Elsevier B.V. All rights reserved.
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.
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.
Management intensity and vegetation complexity affect web-building spiders and their prey.
Diehl, Eva; Mader, Viktoria L; Wolters, Volkmar; Birkhofer, Klaus
2013-10-01
Agricultural management and vegetation complexity affect arthropod diversity and may alter trophic interactions between predators and their prey. Web-building spiders are abundant generalist predators and important natural enemies of pests. We analyzed how management intensity (tillage, cutting of the vegetation, grazing by cattle, and synthetic and organic inputs) and vegetation complexity (plant species richness, vegetation height, coverage, and density) affect rarefied richness and composition of web-building spiders and their prey with respect to prey availability and aphid predation in 12 habitats, ranging from an uncut fallow to a conventionally managed maize field. Spiders and prey from webs were collected manually and the potential prey were quantified using sticky traps. The species richness of web-building spiders and the order richness of prey increased with plant diversity and vegetation coverage. Prey order richness was lower at tilled compared to no-till sites. Hemipterans (primarily aphids) were overrepresented, while dipterans, hymenopterans, and thysanopterans were underrepresented in webs compared to sticky traps. The per spider capture efficiency for aphids was higher at tilled than at no-till sites and decreased with vegetation complexity. After accounting for local densities, 1.8 times more aphids were captured at uncut compared to cut sites. Our results emphasize the functional role of web-building spiders in aphid predation, but suggest negative effects of cutting or harvesting. We conclude that reduced management intensity and increased vegetation complexity help to conserve local invertebrate diversity, and that web-building spiders at sites under low management intensity (e.g., semi-natural habitats) contribute to aphid suppression at the landscape scale.
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…
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.
ERIC Educational Resources Information Center
Fuller, Alison; Unwin, Lorna
2010-01-01
This paper explores the concept of apprenticeship in the context of the professional formation of knowledge workers. It draws on evidence from research conducted in two knowledge intensive organizations: a research-intensive, elite university; and a "cutting edge" software engineering company. In the former, we investigated the learning…
Cathryn H. Greenberg; Daniel G. Neary; Lawrence D. Harris; Steven P. Linda
1994-01-01
We hypothesized that clear-cutting mimics natural high-intensity disturbance by wildfire followed by salvage logging in sand pine scrub, and tested whether vegetation adapted to recovery from fire would respond similarly to another type of biomass removal. We measured plant community composition and structural characteristics in three replicated disturbance treatments...
Figure correction of a metallic ellipsoidal neutron focusing mirror
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Jiang, E-mail: jiang.guo@riken.jp; Yamagata, Yutaka; Morita, Shin-ya
2015-06-15
An increasing number of neutron focusing mirrors is being adopted in neutron scattering experiments in order to provide high fluxes at sample positions, reduce measurement time, and/or increase statistical reliability. To realize a small focusing spot and high beam intensity, mirrors with both high form accuracy and low surface roughness are required. To achieve this, we propose a new figure correction technique to fabricate a two-dimensional neutron focusing mirror made with electroless nickel-phosphorus (NiP) by effectively combining ultraprecision shaper cutting and fine polishing. An arc envelope shaper cutting method is introduced to generate high form accuracy, while a fine polishingmore » method, in which the material is removed effectively without losing profile accuracy, is developed to reduce the surface roughness of the mirror. High form accuracy in the minor-axis and the major-axis is obtained through tool profile error compensation and corrective polishing, respectively, and low surface roughness is acquired under a low polishing load. As a result, an ellipsoidal neutron focusing mirror is successfully fabricated with high form accuracy of 0.5 μm peak-to-valley and low surface roughness of 0.2 nm root-mean-square.« less
DPSSL for direct dicing and drilling of dielectrics
NASA Astrophysics Data System (ADS)
Ashkenasi, David; Schwagmeier, M.
2007-02-01
New strategies in laser micro processing of glasses and other optically transparent materials are being developed with increasing interest and intensity using diode pumped solid state laser (DPSSL) systems generating short or ultra-short pulses in the optical spectra at good beam quality. Utilizing non-linear absorption channels, it can be demonstrated that ns green (532 nm) laser light can scribe, dice, full body cut and drill (flat) borofloat and borosilicate glasses at good quality. Outside of the correct choice in laser parameters, an intelligent laser beam management plays an important role in successful micro processing of glass. This application characterizes a very interesting alternative where standard methods demonstrate severe limitations such as diamond dicing, CO2 laser treatment or water jet cutting, especially for certain type of optical materials and/or geometric conditions. Application near processing examples using different DPSSL systems generating ns pulsed light at 532 nm in TEM 00 at average powers up to 10 W are presented and discussed in respect to potential applications in display technology, micro electronics and optics.
Multicriteria evaluation of simulated logging scenarios in a tropical rain forest.
Huth, Andreas; Drechsler, Martin; Köhler, Peter
2004-07-01
Forest growth models are useful tools for investigating the long-term impacts of logging. In this paper, the results of the rain forest growth model FORMIND were assessed by a multicriteria decision analysis. The main processes covered by FORMIND include tree growth, mortality, regeneration and competition. Tree growth is calculated based on a carbon balance approach. Trees compete for light and space; dying large trees fall down and create gaps in the forest. Sixty-four different logging scenarios for an initially undisturbed forest stand at Deramakot (Malaysia) were simulated. The scenarios differ regarding the logging cycle, logging method, cutting limit and logging intensity. We characterise the impacts with four criteria describing the yield, canopy opening and changes in species composition. Multicriteria decision analysis was used for the first time to evaluate the scenarios and identify the efficient ones. Our results plainly show that reduced-impact logging scenarios are more 'efficient' than the others, since in these scenarios forest damage is minimised without significantly reducing yield. Nevertheless, there is a trade-off between yield and achieving a desired ecological state of logged forest; the ecological state of the logged forests can only be improved by reducing yields and enlarging the logging cycles. Our study also demonstrates that high cutting limits or low logging intensities cannot compensate for the high level of damage caused by conventional logging techniques.
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
NASA Astrophysics Data System (ADS)
Alday, Josu G.; Martínez-Ruiz, Carolina; Marrs, Rob H.; Bravo, Felipe
2010-05-01
Understorey plant species composition is an important part of forest ecosystems and its conservation is becoming an increasingly frequent objective in forest management plans. However, there is a lack of knowledge of the effect of timber harvesting on the characteristic understorey species in the Mediterranean region. We investigated the effects of three different harvest intensities on the short-term dynamics of understorey vegetation in a natural Maritime pine forest in Spain, and compared the results with uncut controls. Clear-cutting induced both qualitative and quantitative differences with respect to the controls, but intermediate levels of harvesting (25% and 50% removal) induced only quantitative differences. Harvesting reduced the frequency and cover of 56% of characteristic forest species, but only 22% showed an increase. Of the most abundant plant families only the Fabaceae showed a significant response with respect to harvesting intensity. Our findings suggest that Light- and Medium-harvest regimes are better management options than clear-cutting if the aim is to conserve the understorey vegetation.
Asymmetrically cut crystal pair as x-ray magnifier for imaging at high intensity laser facilitiesa)
NASA Astrophysics Data System (ADS)
Szabo, C. I.; Feldman, U.; Seely, J. F.; Curry, J. J.; Hudson, L. T.; Henins, A.
2010-10-01
The potential of an x-ray magnifier prepared from a pair of asymmetrically cut crystals is studied to explore high energy x-ray imaging capabilities at high intensity laser facilities. OMEGA-EP and NIF when irradiating mid and high Z targets can be a source of high-energy x-rays whose production mechanisms and use as backlighters are a subject of active research. This paper studies the properties and potential of existing asymmetric cut crystal pairs from the National Institute of Standards and Technology (NIST) built in a new enclosure for imaging x-ray sources. The technique of the x-ray magnifier has been described previously. This new approach is aimed to find a design that could be used at laser facilities by magnifying the x-ray source into a screen far away from the target chamber center, with fixed magnification defined by the crystals' lattice spacing and the asymmetry angles. The magnified image is monochromatic and the imaging wavelength is set by crystal asymmetry and incidence angles. First laboratory results are presented and discussed.
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...
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.
Pilot study of manual sugarcane harvesting using biomechanical analysis.
Clementson, C L; Hansen, A C
2008-07-01
In many countries, sugar cane harvesting is a very labor-intensive activity in which workers usually become fatigued after manually cutting the cane for a few hours. They need frequent pauses for rest, and they experience sustained injuries from excessive stress on the joints and muscles of the body. The cutting tool and motion involved directly influence the stresses created. A cutting tool that has not been designed by taking into consideration occupational biomechanics can lead to unnecessary strains in the body's muscle system, resulting in injuries. The purpose of this research was to carry out a pilot study of the impact of two common manual sugarcane cutting tools and the cutting posture they induce on the body with the aid of biomechanics. The machete and the cutlass from South Africa and Guyana, respectively, were examined to determine the cutting forces. Using static strength prediction modeling, the body stress levels at the point of cut in the cutting motion were determined. The cutting postures of three subjects were contrasted, their extreme postures were identified, and suggestions were made to improve the ergonomics of the cutting activity. The results of this pilot study showed that the cutlass required less cutting force than the machete because of the slicing cut provided by the curved blade edge of the cutlass. However, the biomechanical analysis indicated that the bent blade of the machete required less flexion of the back and therefore was likely to cause less back fatigue and injury. An improved design of the sugarcane manual harvesting tool should incorporate the bend of the machete to reduce flexion and a curved cutting edge that provides a slicing cut.
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
NASA Astrophysics Data System (ADS)
Tahir, Abdul Fattah Mohd; Aqida, Syarifah Nur
2017-07-01
In hot press forming, changes of mechanical properties in boron steel blanks have been a setback in trimming the final shape components. This paper presents investigation of kerf width and heat affected zone (HAZ) of ultra high strength 22MnB5 steel cutting. Sample cutting was conducted using a 4 kW Carbon Dioxide (CO2) laser machine with 10.6 μm wavelength with the laser spot size of 0.2 mm. A response surface methodology (RSM) using three level Box-Behnken design of experiment was developed with three factors of peak power, cutting speed and duty cycle. The parameters were optimised for minimum kerf width and HAZ formation. Optical evaluation using MITUTOYO TM 505 were conducted to measure the kerf width and HAZ region. From the findings, laser duty cycle was crucial to determine cutting quality of ultra-high strength steel; followed by cutting speed and laser power. Meanwhile, low power intensity with continuous wave contributes the narrowest kerf width formation and least HAZ region.
Furtner, J; Schöpf, V; Preusser, M; Asenbaum, U; Woitek, R; Wöhrer, A; Hainfellner, J A; Wolfsberger, S; Prayer, D
2014-05-01
Using conventional MRI methods, the differentiation of primary cerebral lymphomas (PCNSL) and other primary brain tumors, such as glioblastomas, is difficult due to overlapping imaging characteristics. This study was designed to discriminate tumor entities using normalized vascular intratumoral signal intensity values (nVITS) obtained from pulsed arterial spin labeling (PASL), combined with intratumoral susceptibility signals (ITSS) from susceptibility-weighted imaging (SWI). Thirty consecutive patients with glioblastoma (n=22) and PCNSL (n=8), histologically classified according to the WHO brain tumor classification, were included. MRIs were acquired on a 3T scanner, and included PASL and SWI sequences. nVITS was defined by the signal intensity ratio between the tumor and the contralateral normal brain tissue, as obtained by PASL images. ITSS was determined as intratumoral low signal intensity structures detected on SWI sequences and were divided into four different grades. Potential differences in the nVITS and ITSS between glioblastomas and PCNSLs were revealed using statistical testing. To determine sensitivity, specificity, and diagnostic accuracy, as well as an optimum cut-off value for the differentiation of PCNSL and glioblastoma, a receiver operating characteristic analysis was used. We found that nVITS (p=0.011) and ITSS (p=0.001) values were significantly higher in glioblastoma than in PCNSL. The optimal cut-off value for nVITS was 1.41 and 1.5 for ITSS, with a sensitivity, specificity, and accuracy of more than 95%. These findings indicate that nVITS values have a comparable diagnostic accuracy to ITSS values in differentiating glioblastoma and PCNSL, offering a completely non-invasive and fast assessment of tumoral vascularity in a clinical setting. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Erbium ion implantation into different crystallographic cuts of lithium niobate
NASA Astrophysics Data System (ADS)
Nekvindova, P.; Svecova, B.; Cajzl, J.; Mackova, A.; Malinsky, P.; Oswald, J.; Kolistsch, A.; Spirkova, J.
2012-02-01
Single crystals like lithium niobate are frequently doped with optically active rare-earth or transition-metal ions for a variety of applications in optical devices such as solid-state lasers, amplifiers or sensors. To exploit the potential of the Er:LiNbO 3, one must ensure high intensity of the 1.5 μm luminescence as an inevitable prerequisite. One of the important factors influencing the luminescence properties of a lasing ion is the crystal field of the surrounding, which is inevitably determined by the crystal structure of the pertinent material. From that point it is clear that it cannot be easy to affect the resulting luminescence properties - intensity or position of the luminescence band - without changing the structure of the substrate. However, there is a possibility to utilise a potential of the ion implantation of the lasing ions, optionally accompanied with a sensitising one, that can, besides the doping, also modify the structure of the treated area od the crystal. This effect can be eventually enhanced by a post-implantation annealing that may help to recover the damaged structure and hence to improve the desired luminescence. In this paper we are going to report on our experiments with ion-implantation technique followed with subsequent annealing could be a useful way to influence the crystal field of LN. Optically active Er:LiNbO 3 layers were fabricated by medium energy implantation under various experimental conditions. The Er + ions were implanted at energies of 330 and 500 keV with fluences ranging from 1.0 × 10 15 to 1.0 × 10 16 ion cm -2 into LiNbO 3 single-crystal cuts of both common and special orientations. The as-implanted samples were annealed in air and oxygen at two different temperatures (350 and 600 °C) for 5 h. The depth concentration profiles of the implanted erbium were measured by Rutherford Backscattering Spectroscopy (RBS) using 2 MeV He + ions. The photoluminescence spectra of the samples were measured to determine the emission of 1.5 μm. It has been shown that the projected range Rp of the implanted erbium depends on the beam energies of implantation. The concentration of the implanted erbium corresponds well with the fluence and is similar in all of the cuts of lithium niobate used. What was different were the intensities of the 1.5 μm luminescence bands not only before and after the annealing but also in various types of the crystal cuts. The cut perpendicular to the cleavage plane <10-14> exhibited the best luminescence properties for all of the experimental conditions used. In order to study the damage introduced by the implantation process, the influence of the annealing procedure on the recovery of the host lattice was examined by RBS/channelling. The RBS/channelling method serves to determine the disorder density in the as-implanted surface layer.
Simple to complex modeling of breathing volume using a motion sensor.
John, Dinesh; Staudenmayer, John; Freedson, Patty
2013-06-01
To compare simple and complex modeling techniques to estimate categories of low, medium, and high ventilation (VE) from ActiGraph™ activity counts. Vertical axis ActiGraph™ GT1M activity counts, oxygen consumption and VE were measured during treadmill walking and running, sports, household chores and labor-intensive employment activities. Categories of low (<19.3 l/min), medium (19.3 to 35.4 l/min) and high (>35.4 l/min) VEs were derived from activity intensity classifications (light <2.9 METs, moderate 3.0 to 5.9 METs and vigorous >6.0 METs). We examined the accuracy of two simple techniques (multiple regression and activity count cut-point analyses) and one complex (random forest technique) modeling technique in predicting VE from activity counts. Prediction accuracy of the complex random forest technique was marginally better than the simple multiple regression method. Both techniques accurately predicted VE categories almost 80% of the time. The multiple regression and random forest techniques were more accurate (85 to 88%) in predicting medium VE. Both techniques predicted the high VE (70 to 73%) with greater accuracy than low VE (57 to 60%). Actigraph™ cut-points for light, medium and high VEs were <1381, 1381 to 3660 and >3660 cpm. There were minor differences in prediction accuracy between the multiple regression and the random forest technique. This study provides methods to objectively estimate VE categories using activity monitors that can easily be deployed in the field. Objective estimates of VE should provide a better understanding of the dose-response relationship between internal exposure to pollutants and disease. Copyright © 2013 Elsevier B.V. All rights reserved.
Fracture Capabilities in Grizzly with the extended Finite Element Method (X-FEM)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dolbow, John; Zhang, Ziyu; Spencer, Benjamin
Efforts are underway to develop fracture mechanics capabilities in the Grizzly code to enable it to be used to perform deterministic fracture assessments of degraded reactor pressure vessels (RPVs). A capability was previously developed to calculate three-dimensional interaction- integrals to extract mixed-mode stress-intensity factors. This capability requires the use of a finite element mesh that conforms to the crack geometry. The eXtended Finite Element Method (X-FEM) provides a means to represent a crack geometry without explicitly fitting the finite element mesh to it. This is effected by enhancing the element kinematics to represent jump discontinuities at arbitrary locations inside ofmore » the element, as well as the incorporation of asymptotic near-tip fields to better capture crack singularities. In this work, use of only the discontinuous enrichment functions was examined to see how accurate stress intensity factors could still be calculated. This report documents the following work to enhance Grizzly’s engineering fracture capabilities by introducing arbitrary jump discontinuities for prescribed crack geometries; X-FEM Mesh Cutting in 3D: to enhance the kinematics of elements that are intersected by arbitrary crack geometries, a mesh cutting algorithm was implemented in Grizzly. The algorithm introduces new virtual nodes and creates partial elements, and then creates a new mesh connectivity; Interaction Integral Modifications: the existing code for evaluating the interaction integral in Grizzly was based on the assumption of a mesh that was fitted to the crack geometry. Modifications were made to allow for the possibility of a crack front that passes arbitrarily through the mesh; and Benchmarking for 3D Fracture: the new capabilities were benchmarked against mixed-mode three-dimensional fracture problems with known analytical solutions.« less
Zhao, Yitian; Zheng, Yalin; Liu, Yonghuai; Yang, Jian; Zhao, Yifan; Chen, Duanduan; Wang, Yongtian
2017-01-01
Leakage in retinal angiography currently is a key feature for confirming the activities of lesions in the management of a wide range of retinal diseases, such as diabetic maculopathy and paediatric malarial retinopathy. This paper proposes a new saliency-based method for the detection of leakage in fluorescein angiography. A superpixel approach is firstly employed to divide the image into meaningful patches (or superpixels) at different levels. Two saliency cues, intensity and compactness, are then proposed for the estimation of the saliency map of each individual superpixel at each level. The saliency maps at different levels over the same cues are fused using an averaging operator. The two saliency maps over different cues are fused using a pixel-wise multiplication operator. Leaking regions are finally detected by thresholding the saliency map followed by a graph-cut segmentation. The proposed method has been validated using the only two publicly available datasets: one for malarial retinopathy and the other for diabetic retinopathy. The experimental results show that it outperforms one of the latest competitors and performs as well as a human expert for leakage detection and outperforms several state-of-the-art methods for saliency detection.
Development of a lemon cutting machine.
Hrishikesh Tavanandi, A; Deepak, S; Venkateshmurthy, K; Raghavarao, K S M S
2014-12-01
Cutting of lemon and other similar fruits is conventionally done manually by sharp knife, which is labor intensive and often un-hygienic. In the present work, a device has been designed and developed for cutting of lemon hygienically into four pieces of similar shape based on stationery cutters and rotating centralizing/locating slit plate concept. Machine has a unique knife assembly consisting of two bird wing shaped knives, joined by welding perpendicularly to a vertical knife, so that the lemon can be cut into four pieces in a single sweep. Six numbers of rotating centralizing/locating slit plates are welded on to the side plates and the plates carry a groove on its inner face, to enable the wing shaped knife to complete the horizontal cut. The rotating slit plates, having centralizing angle of 90°, are rotated by an electric geared motor. The prototype machine has capacity of over 5,000 lemons/h with a power consumption of 0.11 kW.
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.
Bugmyrin, S V; Bespiatova, L A; Anikanova, V S; Ieshko, E P
2009-01-01
Data of long-term investigations (1998-2004) on the abundance of the taiga tick larvae and nymphs in the cut-over lands of different age in the middle taiga subzone of Karelia (62 degrees 04'S; 33 degrees 55'W) are presented. The investigation was carried out on three model cut-over lands of different age: 1) "young" cut-over land; age of cut-over in the beginning of investigation is 7 years; Betula-Deschampsia cespitosa-Agrostis tenuis; 2) "middle" cut-over land; age of cut-over is 12 years; Salix-Deschampsia cespitosa-Agrostis tenuis; 3) "old" cut-over land; age of cut-over 25 years; Alnus incana-Rubus idaeus-grass. The number of ticks was estimated by using common parasitological indices: prevalence, abundance, and index of feeding intensity (the tick abundance multiply by the number of small mammals per hundred traps-nights). In the beginning of investigation the "young" cut-over land was a typical meadow association. The lowest tick abundance was recorded here. That was a result of unfavorable abiotic conditions and low number of small mammals in the beginning of summer. "Middle" cut-over land is characterized by the highest number of the tick larvae, which is the evidence for high number of the hosts of tick imago. "Old" cut-over land has the optimum conditions for development of taiga ticks. High abundance of the ticks (larvae and nymphs) was recorded during the whole period of investigations. The number of preimaginal ticks is shown to be much higher in cut-over lands as compared with that in mixed and coniferous forests, due to the higher number of small mammals.
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...
Recruitment of single muscle fibers during submaximal cycling exercise.
Altenburg, T M; Degens, H; van Mechelen, W; Sargeant, A J; de Haan, A
2007-11-01
In literature, an inconsistency exists in the submaximal exercise intensity at which type II fibers are activated. In the present study, the recruitment of type I and II fibers was investigated from the very beginning and throughout a 45-min cycle exercise at 75% of the maximal oxygen uptake, which corresponded to 38% of the maximal dynamic muscle force. Biopsies of the vastus lateralis muscle were taken from six subjects at rest and during the exercise, two at each time point. From the first biopsy single fibers were isolated and characterized as type I and II, and phosphocreatine-to-creatine (PCr/Cr) ratios and periodic acid-Schiff (PAS) stain intensities were measured. Cross sections were cut from the second biopsy, individual fibers were characterized as type I and II, and PAS stain intensities were measured. A decline in PCr/Cr ratio and in PAS stain intensity was used as indication of fiber recruitment. Within 1 min of exercise both type I and, although to a lesser extent, type II fibers were recruited. Furthermore, the PCr/Cr ratio revealed that the same proportion of fibers was recruited during the whole 45 min of exercise, indicating a rather constant recruitment. The PAS staining, however, proved inadequate to fully demonstrate fiber recruitment even after 45 min of exercise. We conclude that during cycling exercise a greater proportion of type II fibers is recruited than previously reported for isometric contractions, probably because of the dynamic character of the exercise. Furthermore, the PCr/Cr ratio method is more sensitive in determining fiber activation than the PAS stain intensity method.
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.
Headspace profiling of cocaine samples for intelligence purposes.
Dujourdy, Laurence; Besacier, Fabrice
2008-08-06
A method for determination of residual solvents in illicit hydrochloride cocaine samples using static headspace-gas chromatography (HS-GC) associated with a storage computerized procedure is described for the profiling and comparison of seizures. The system involves a gas chromatographic separation of 18 occluded solvents followed by fully automatic data analysis and transfer to a PHP/MySQL database. First, a fractional factorial design was used to evaluate the main effects of some critical method parameters (salt choice, vial agitation intensity, oven temperature, pressurization and loop equilibration) on the results with a minimum of experiments. The method was then validated for tactical intelligence purposes (batch comparison) via several studies: selection of solvents and mathematical comparison tool, reproducibility and "cutting" influence studies. The decision threshold to determine the similarity of two samples was set and false positives and negatives evaluated. Finally, application of the method to distinguish geographical origins is discussed.
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
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.
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.
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.
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.
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
NASA Astrophysics Data System (ADS)
Zeeman, M. J.; Tuzson, B.; Eugster, W.; Werner, R. A.; Buchmann, N.; Emmenegger, L.
2007-12-01
To improve our understanding of greenhouse gas dynamics of managed ecosystems such as grasslands, we not only need to investigate the effects of management (e.g., grass cuts) and weather events (e.g., rainy days) on carbon dioxide fluxes, but also need to increase the time resolution of our measurements. Thus, for the first time, we assessed respiration and assimilation fluxes with high time resolution (5Hz) stable isotope measurements at an intensively managed farmland in Switzerland (Chamau, 400m ASL). Two different methods were used to quantify fluxes of carbon dioxide and associated fluxes of stable carbon isotopes: (1) the flux gradient method, and (2) the eddy covariance method. During a week long intensive measurement campaign, we (1) measured mixing ratios of carbon dioxide isotopomers (12C16O2, 12C16O18O, 13C16O2) with a Quantum Cascade Laser (QCL, Aerodyne Inc.) spectroscope and (2) collected air samples for isotope analyses (13C/12C) and (18O/16O) of carbon dioxide by Isotope Ratio Mass Spectrometry (IRMS, Finnigan) every two hours, concurrently along a height profile (z = 0.05; 0.10; 0.31; 2.15m). In the following week, the QCL setup was used for closed-path eddy covariance flux measurement of the carbon dioxide isotopomers, with the air inlet located next to an open-path Infra Red Gas Analyzers (IRGA, LiCor 7500) used simultaneously for carbon dioxide measurements. During this second week, an area of grass inside the footprint was cut and harvested after several days. The first results of in-field continuous QCL measurements of carbon dioxide mixing ratios and their stable isotopic ratios show good agreement with IRGA measurements and isotope analysis of flask samples by IRMS. Thus, QCL spectroscopy is a very promising tool for stable isotope flux investigations.
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.
A shape prior-based MRF model for 3D masseter muscle segmentation
NASA Astrophysics Data System (ADS)
Majeed, Tahir; Fundana, Ketut; Lüthi, Marcel; Beinemann, Jörg; Cattin, Philippe
2012-02-01
Medical image segmentation is generally an ill-posed problem that can only be solved by incorporating prior knowledge. The ambiguities arise due to the presence of noise, weak edges, imaging artifacts, inhomogeneous interior and adjacent anatomical structures having similar intensity profile as the target structure. In this paper we propose a novel approach to segment the masseter muscle using the graph-cut incorporating additional 3D shape priors in CT datasets, which is robust to noise; artifacts; and shape deformations. The main contribution of this paper is in translating the 3D shape knowledge into both unary and pairwise potentials of the Markov Random Field (MRF). The segmentation task is casted as a Maximum-A-Posteriori (MAP) estimation of the MRF. Graph-cut is then used to obtain the global minimum which results in the segmentation of the masseter muscle. The method is tested on 21 CT datasets of the masseter muscle, which are noisy with almost all possessing mild to severe imaging artifacts such as high-density artifacts caused by e.g. the very common dental fillings and dental implants. We show that the proposed technique produces clinically acceptable results to the challenging problem of muscle segmentation, and further provide a quantitative and qualitative comparison with other methods. We statistically show that adding additional shape prior into both unary and pairwise potentials can increase the robustness of the proposed method in noisy datasets.
Mark Alexander Butler; Joseph Dahlen; Richard F. Daniels; Thomas L. Eberhardt; Finto Antony
2016-01-01
Loblolly pine is increasingly grown on intensively managed plantation forests that yield excellent growth; however, lumber cut from these trees often contains a large percentage of juvenile wood which negatively impacts strength and stiffness. Because of changing forest management and mill practices the design values for visually graded southern pine were updated in...
Intensive Cleaning Increses Sapling Growth and Browse Production in the Southern Appalachians
Lino Della-Bianca
1969-01-01
All woody stems except selected crop trees were cut in an 11-year-old mixed-hardwood sapling stand in the Southern Appalachians to determine the effect of intensive cleaning on crop-tree growth and deer-browse production. During the 6-year post-cleaning period, crop trees in uncleaned compartments produced significantly more basal area and grew more in diameter than...
Patrick H. Brose
2016-01-01
In the shelterwood-burn technique, a moderate- to high-intensity growing-season prescribed fire is essential to achieve desired oak regeneration goals. These levels of fire intensity are dependent on the increased fuel loadings created by the preceding first removal cut. However, the loadings of forest fuels and their fluctuation during implementation of the...
... metal ores. Silica is a main part of sand, so glass workers and sand-blasters are also exposed to silica. Three types ... Glass manufacturing Mining Quarrying Road and building construction Sand blasting Stone cutting Intense exposure to silica can ...
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…
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.
Gender Difference in Internet Use and Internet Problems among Quebec High School Students.
Dufour, Magali; Brunelle, Natacha; Tremblay, Joel; Leclerc, Danielle; Cousineau, Marie-Marthe; Khazaal, Yasser; Légaré, Andrée-Anne; Rousseau, Michel; Berbiche, Djamal
2016-10-01
There are presently no data available concerning Internet addiction (IA) problems among adolescents in Canada and the province of Quebec. The goal of this study is thus to document and compare the influence of gender on Internet use and addiction. The study data were collected from a larger research project on gambling among adolescents. Activities conducted online (applications used and time spent) as well as answers to the Internet Addiction Test (IAT) were collected from 3938 adolescents from grades 9 to 11. The two most often employed cut-off points for the IAT in the literature were documented: (40-69 and 70+) and (50+). Boys spent significantly more time on the Internet than did girls. A greater proportion of the girls made intense use of social networks, whereas a greater proportion of the boys made intense use of massively multiplayer online role-playing games, online games, and adult sites. The proportion of adolescents with a potential IA problem varied according to the cut-off employed. When the cut-off was set at 70+, 1.3% of the adolescents were considered to have an IA, while 41.7% were seen to be at risk. At a 50+ cut-off, 18% of the adolescents were considered to have a problem. There was no significant difference between the genders concerning the proportion of adolescents considered to be at risk or presenting IA problems. Finally, analysis of the percentile ranks would seem to show that a cut-off of 50+ better describes the category of young people at risk. The results of this study make it possible to document Internet use and IA in a large number of Quebec adolescents. © The Author(s) 2016.
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.
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.
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.
2011-01-01
Background Bovine tuberculosis (BTB) is endemic in Ethiopian cattle. The aim of this study was to assess BTB prevalence at an intensive contact interface in Meskan Woreda (district) in cattle, small ruminants and suspected TB-lymphadenitis (TBLN) human patients. Methods The comparative intradermal test (CIDT) was carried out for all animals involved in the cross-sectional study and results interpreted using a > 4 mm and a > 2 mm cut-off. One PPD positive goat was slaughtered and lymph nodes subjected to culture and molecular typing. In the same villages, people with lymphadenitis were subjected to clinical examination. Fine needle aspirates (FNA) were taken from suspected TBLN and analyzed by smear microscopy and molecular typing. Results A total of 1214 cattle and 406 small ruminants were tested for BTB. In cattle, overall individual prevalence (> 2 mm cut-off) was 6.8% (CI: 5.4-8.5%) with 100% herd prevalence. Only three small ruminants (2 sheep and 1 goat) were reactors. The overall individual prevalence in small ruminants (> 2 mm cut-off) was 0.4% (CI: 0.03-5.1%) with 25% herd prevalence. Cattle from owners with PPD positive small ruminants were all PPD negative. 83% of the owners kept their sheep and goats inside their house at night and 5% drank regularly goat milk. FNAs were taken from 33 TBLN suspected cases out of a total of 127 screened individuals with lymph node swellings. Based on cytology results, 12 were confirmed TBLN cases. Nine out of 33 cultures were AFB positive. Culture positive samples were subjected to molecular typing and they all yielded M. tuberculosis. M. tuberculosis was also isolated from the goat that was slaughtered. Conclusions This study highlighted a low BTB prevalence in sheep and goats despite intensive contact with cattle reactors. TBLN in humans was caused entirely by M. tuberculosis, the human pathogen. M. tuberculosis seems to circulate also in livestock but their role at the interface is unknown. PMID:22085784
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.
Summerville, Keith S
2013-07-01
A common measure of ecosystem resilience is the time course to recovery for a system that has been previously disturbed. The goal of this study was to assess whether forest lepidopteran communities displayed three different forms of resilience following experimental timber harvest. Specifically, I examined whether moth species assemblages returned to pre-logging composition (compositional resilience), species richness (structural resilience), and guild diversity (functional resilience) after forest management. Lepidoptera were sampled from 16 forest stands managed with one of four harvest treatments: no logging, clear-cutting, shelterwood harvests, and group selection harvests. Moths were sampled from all forest stands one year prior to harvest in 2007 and immediately postharvest in 2009-2011. Moth community composition only appeared to be resilient to timber harvest in stands managed with shelterwood methods (15% biomass removed) or in the unlogged stands within managed concession units. Both total species richness and species richness of Quercus-feeding moths also appeared to recover to a near original condition three years post-shelterwood logging. In contrast, moth assemblages in clear-cut stands and group selection stands (80% biomass removed) remained impoverished. Tests of functional resilience suggested that richness of species known to be pollinators was largely unaffected by timber management, and the number of moth species known to feed on herbaceous vegetation doubled in stands logged using group selection methods. Dietary specialists were disproportionately abundant in the unlogged stands postharvest, suggesting that species with more narrow dietary niches have the lowest resilience to timber management. These results suggest that most methods of forest management have short-term negative impacts on woody-plant-feeding Lepidoptera, but that the effects are limited to a few years when the harvest method involves shelterwood cuts. Herbaceous-feeding Lepidoptera appear to quickly colonize stands managed with group selection or clear-cutting, so loss of species richness in stands managed with either of these treatments may be less than predicted based on level of timber being removed. Recovery of moth assemblages in more highly disturbed stands will require longer time periods and techniques such as group selection harvests, where upwards of 80% of the standing bole is removed, may not be consistent with conservation goals.
Albà, Xènia; Figueras I Ventura, Rosa M; Lekadir, Karim; Tobon-Gomez, Catalina; Hoogendoorn, Corné; Frangi, Alejandro F
2014-12-01
Magnetic resonance imaging (MRI), specifically late-enhanced MRI, is the standard clinical imaging protocol to assess cardiac viability. Segmentation of myocardial walls is a prerequisite for this assessment. Automatic and robust multisequence segmentation is required to support processing massive quantities of data. A generic rule-based framework to automatically segment the left ventricle myocardium is presented here. We use intensity information, and include shape and interslice smoothness constraints, providing robustness to subject- and study-specific changes. Our automatic initialization considers the geometrical and appearance properties of the left ventricle, as well as interslice information. The segmentation algorithm uses a decoupled, modified graph cut approach with control points, providing a good balance between flexibility and robustness. The method was evaluated on late-enhanced MRI images from a 20-patient in-house database, and on cine-MRI images from a 15-patient open access database, both using as reference manually delineated contours. Segmentation agreement, measured using the Dice coefficient, was 0.81±0.05 and 0.92±0.04 for late-enhanced MRI and cine-MRI, respectively. The method was also compared favorably to a three-dimensional Active Shape Model approach. The experimental validation with two magnetic resonance sequences demonstrates increased accuracy and versatility. © 2013 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Liu, Pengxiang; Xu, Degang; Liu, Changming; Lv, Da; Lv, Yingjin; Wang, Peng; Yao, Jianquan
2011-08-01
In this paper, we investigated p-polarized Cherenkov radiation excited by an ultra-short laser pulse focused into a line in an LiNbO3 crystal. The geometries of p- and s-polarized THz generation were both analyzed. We did further calculations on p-polarized THz radiation and designed a Brewster-cut geometry. The radiated energy and conversion efficiency were roughly estimated. Compared with s-polarized waves radiated from a Cherenkov-cut crystal, p-polarized THz radiation has lower energy and conversion efficiency, but higher intensity and better beam quality. The effect of angular dispersion between the spectral components of the THz pulse after refraction at the Brewster surface was also discussed.
Verschueren, Sabine M. P.; Degens, Hans; Morse, Christopher I.; Onambélé, Gladys L.
2017-01-01
Accurate monitoring of sedentary behaviour and physical activity is key to investigate their exact role in healthy ageing. To date, accelerometers using cut-off point models are most preferred for this, however, machine learning seems a highly promising future alternative. Hence, the current study compared between cut-off point and machine learning algorithms, for optimal quantification of sedentary behaviour and physical activity intensities in the elderly. Thus, in a heterogeneous sample of forty participants (aged ≥60 years, 50% female) energy expenditure during laboratory-based activities (ranging from sedentary behaviour through to moderate-to-vigorous physical activity) was estimated by indirect calorimetry, whilst wearing triaxial thigh-mounted accelerometers. Three cut-off point algorithms and a Random Forest machine learning model were developed and cross-validated using the collected data. Detailed analyses were performed to check algorithm robustness, and examine and benchmark both overall and participant-specific balanced accuracies. This revealed that the four models can at least be used to confidently monitor sedentary behaviour and moderate-to-vigorous physical activity. Nevertheless, the machine learning algorithm outperformed the cut-off point models by being robust for all individual’s physiological and non-physiological characteristics and showing more performance of an acceptable level over the whole range of physical activity intensities. Therefore, we propose that Random Forest machine learning may be optimal for objective assessment of sedentary behaviour and physical activity in older adults using thigh-mounted triaxial accelerometry. PMID:29155839
Wullems, Jorgen A; Verschueren, Sabine M P; Degens, Hans; Morse, Christopher I; Onambélé, Gladys L
2017-01-01
Accurate monitoring of sedentary behaviour and physical activity is key to investigate their exact role in healthy ageing. To date, accelerometers using cut-off point models are most preferred for this, however, machine learning seems a highly promising future alternative. Hence, the current study compared between cut-off point and machine learning algorithms, for optimal quantification of sedentary behaviour and physical activity intensities in the elderly. Thus, in a heterogeneous sample of forty participants (aged ≥60 years, 50% female) energy expenditure during laboratory-based activities (ranging from sedentary behaviour through to moderate-to-vigorous physical activity) was estimated by indirect calorimetry, whilst wearing triaxial thigh-mounted accelerometers. Three cut-off point algorithms and a Random Forest machine learning model were developed and cross-validated using the collected data. Detailed analyses were performed to check algorithm robustness, and examine and benchmark both overall and participant-specific balanced accuracies. This revealed that the four models can at least be used to confidently monitor sedentary behaviour and moderate-to-vigorous physical activity. Nevertheless, the machine learning algorithm outperformed the cut-off point models by being robust for all individual's physiological and non-physiological characteristics and showing more performance of an acceptable level over the whole range of physical activity intensities. Therefore, we propose that Random Forest machine learning may be optimal for objective assessment of sedentary behaviour and physical activity in older adults using thigh-mounted triaxial accelerometry.
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.
NASA Astrophysics Data System (ADS)
Vuichard, Nicolas; Soussana, Jean-FrançOis; Ciais, Philippe; Viovy, Nicolas; Ammann, Christof; Calanca, Pierluigi; Clifton-Brown, John; Fuhrer, Jürg; Jones, Mike; Martin, CéCile
2007-03-01
We improved a process-oriented biogeochemical model of carbon and nitrogen cycling in grasslands and tested it against in situ measurements of biomass and CO2 and CH4 fluxes at five European grassland sites. The new version of the model (PASIM) calculates the growth and senescence of aboveground vegetation biomass accounting for sporadic removals when the grassland is cut and for continuous removals when it is grazed. Limitations induced by high leaf area index (LAI), soil water deficits and aging of leaves are also included. We added to this a simple empirical formulation to account for the detrimental impact on vegetation of trampling and excreta by grazing animals. Finally, a more realistic methane emission module than is currently used was introduced on the basis of the quality of the animals' diet. Evaluation of this improved version of PASIM is performed at (1) Laqueuille, France, on grassland continuously grazed by cattle with two plots of intensive and extensive grazing intensities, (2) Oensingen, Switzerland, on cut grassland with two fertilized and nonfertilized plots, and (3) Carlow, Ireland, on grassland that is both cut and grazed by cattle during the growing season. In addition, we compared the modeled animal CH4 emissions with in situ measurements on cattle for two grazing intensities at the grazed grassland site of Laqueuille. Altogether, when all improvements to the PASIM model are included, we found that the new parameterizations resulted into a better fit to the observed seasonal cycle of biomass and of measured CO2 and CH4 fluxes. However, the large uncertainties in measurements of biomass and LAI make simulation of biomass dynamics difficult to make. Also simulations for cut grassland are better than for grazed swards. This work paves the way for simulating greenhouse gas fluxes over grasslands in a spatially explicit manner, in order to quantify and understand the past, present and future role of grasslands in the greenhouse gas budget of the European continent.
Evolution of energy deposition during glass cutting with pulsed femtosecond laser radiation
NASA Astrophysics Data System (ADS)
Kalupka, C.; Großmann, D.; Reininghaus, M.
2017-05-01
We report on investigations of the energy deposition in the volume of thin glass during an ablation cutting process with pulsed femtosecond laser radiation by time-resolved pump-probe shadowgraphy. For a single laser pulse, the temporal evolution of the transient electronic excitation of the glass volume is imaged up to 10 ps after initial excitation. For an increasing number of laser pulses, the spatial excitation of the glass volume significantly changes compared to single pulse irradiation. Sharp spikes are observed, which reduce the transmission of the illuminating probe pulse. This indicates local maxima of the absorption and, therefore, energy deposition of the pump pulse energy in the glass volume. Furthermore, for an increasing number of pulses, different shapes of the surface ablation crater are observed. To study the correlation between the shape of the surface ablation crater and the energy deposition in the glass volume, simulations of the spatial intensity distribution of the pump pulse are executed by means of linear beam propagation method. We show that the transient excitation spikes observed by pump-probe shadowgraphy can be explained by refraction and diffraction of the laser radiation at the surface ablation crater. Our results provide an experimental validation for the physical reason of an ablation stop for an ablation cutting process. Moreover, the simulations allow for the prediction of damage inside the glass volume.
NASA Astrophysics Data System (ADS)
Applbaum, David; Dorman, Lev; Pustil'Nik, Lev; Sternlieb, Abraham; Zagnetko, Alexander; Zukerman, Igor
In Applbaum et al. (2010) it was described how the "SEP-Search" program works automat-ically, determining on the basis of on-line one-minute NM data the beginning of a great SEP event. The "SEP-Search" next uses one-minute data in order to check whether or not the observed increase reflects the beginning of a real great SEP event. If yes, the program "SEP-Research/Spectrum" automatically starts to work on line. We consider two variants: 1) quiet period (no change in cut-off rigidity), 2) disturbed period (characterized with possible changing of cut-off rigidity). We describe the method of determining the spectrum of SEP in the 1st vari-ant (for this we need data for at least two components with different coupling functions). For the 2nd variant we need data for at least three components with different coupling functions. We show that for these purposes one can use data of the total intensity and some different mul-tiplicities, but that it is better to use data from two or three NM with different cut-off rigidities. We describe in detail the algorithms of the program "SEP-Research/Spectrum." We show how this program worked on examples of some historical great SEP events. The work of NM on Mt. Hermon is supported by Israel (Tel Aviv University and ISA) -Italian (UNIRoma-Tre and IFSI-CNR) collaboration.
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.
[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...
Tracking with occlusions via graph cuts.
Papadakis, Nicolas; Bugeau, Aurélie
2011-01-01
This work presents a new method for tracking and segmenting along time-interacting objects within an image sequence. One major contribution of the paper is the formalization of the notion of visible and occluded parts. For each object, we aim at tracking these two parts. Assuming that the velocity of each object is driven by a dynamical law, predictions can be used to guide the successive estimations. Separating these predicted areas into good and bad parts with respect to the final segmentation and representing the objects with their visible and occluded parts permit handling partial and complete occlusions. To achieve this tracking, a label is assigned to each object and an energy function representing the multilabel problem is minimized via a graph cuts optimization. This energy contains terms based on image intensities which enable segmenting and regularizing the visible parts of the objects. It also includes terms dedicated to the management of the occluded and disappearing areas, which are defined on the areas of prediction of the objects. The results on several challenging sequences prove the strength of the proposed approach.
da Silva, Débora Cristina Fernandes; de Arruda, Alex Martins Varela; Gonçalves, Alex Augusto
2017-06-01
The aim of this study was to determine and compare the quality parameters of broiler chicken meat from free-range and industrial poultry system. Proximate composition, color, pH, shear force, microbial quality and sensory characteristics were evaluated. Both free-range and industrial chicken meat presented PSE (pale, soft and exudative) anomaly ( L * > 53). An inverse correlation between lightness, pH and shear force was observed. The free range broiler meat had higher yellow color ( b * 11.56) and shear force (2.75 kgf) and lower red color ( a * 1.65) and pH (5.75) in comparison to the industrial broiler meat, due intensive physical activity on growing phase and influence of the pre-slaughter stress on the rigor mortis. The thigh cut from free range broiler meat showed higher protein levels (18.00%), while to the thigh and drumstick cuts of industrial broiler meat showed higher total fat levels (3.4 and 5.0%, respectively). In general, each strain and chickens producing methods gave the peculiar characteristics to meat (chemical, physical, microbiological and sensorial).
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jing, Qun; University of Chinese Academy of Sciences, Beijing 100049; Department of Physics, School of Science, Shihezi University, Shihezi 832000
2014-11-15
It is an interesting topic to reveal the origin of the SHG intensity enhancement after substitution from alkali and alkali-earth metal atoms to cadmium in a series of apatite-like borates KSr{sub 4}(BO{sub 3}){sub 3}, Ca{sub 5}(BO{sub 3}){sub 3}F, Cd{sub 5}(BO{sub 3}){sub 3}F. Combined with the first-principles method, SHG-density method and real-space atom-cutting method, the electronic structure, the optical properties and the contribution of respective ion and ion groups have been investigated. Second harmonic generation (SHG) responses are mainly attributed to BO{sub 3} groups with π conjugated configuration and their alignment framework. The contributions of A site are more important inmore » CaBOF and CdBOF compounds than in KSrBO. It is also demonstrated that the strong covalent interactions between the boron–oxygen groups and the cadmium atoms contribute the enhancement of SHG responses after substitution from alkali and alkali-earth metal atoms. - graphical abstract: Combined with the first-principles method, SHG-density method and real-space atom-cutting method, the enhancement of SHG response are attributed to the interaction between cadmium and BO{sub 3} groups. - Highlights: • SHG response on a series of apatite-like borates was studied by a SHG-density method. • SHG responses are mainly attributed to BO{sub 3} groups and their alignment framework. • The contributions of A site are more important in CaBOF and CdBOF than in KSrBO. • Covalent interaction between BO and Cd is responsible for SHG of CdBOF.« less
Heat-Assisted Machining for Material Removal Improvement
NASA Astrophysics Data System (ADS)
Mohd Hadzley, A. B.; Hafiz, S. Muhammad; Azahar, W.; Izamshah, R.; Mohd Shahir, K.; Abu, A.
2015-09-01
Heat assisted machining (HAM) is a process where an intense heat source is used to locally soften the workpiece material before machined by high speed cutting tool. In this paper, an HAM machine is developed by modification of small CNC machine with the addition of special jig to hold the heat sources in front of the machine spindle. Preliminary experiment to evaluate the capability of HAM machine to produce groove formation for slotting process was conducted. A block AISI D2 tool steel with100mm (width) × 100mm (length) × 20mm (height) size has been cut by plasma heating with different setting of arc current, feed rate and air pressure. Their effect has been analyzed based on distance of cut (DOC).Experimental results demonstrated the most significant factor that contributed to the DOC is arc current, followed by the feed rate and air pressure. HAM improves the slotting process of AISI D2 by increasing distance of cut due to initial cutting groove that formed during thermal melting and pressurized air from the heat source.
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.
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.
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.
China cuts energy intensity, but overall energy growth continues, report notes
NASA Astrophysics Data System (ADS)
Showstack, Randy
2012-02-01
A new report states that China has cut its energy intensity—defined as energy use per unit of economic output—by 19.1% from 2006 to 2010, reversing the previous upward trend. However, energy use and carbon emissions in the country continue to grow sharply, according to the Climate Policy Initiative's (CPI) Annual Review of Low-Carbon Development in China: 2010, the second of such reports. China nearly hit its goal of a 20% target reduction in energy intensity during that time period, which spanned the country's eleventh Five-Year Period (FYP) for social and economic development, but during that same period energy-related growth in carbon dioxide (CO2) emissions in China increased by 33.6%, from 5.15 billion tons to 6.88 billion tons, said Qi Ye, CPI's Beijing office director, at a 2 February briefing held at the Brookings Institution in Washington, D. C.
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.
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.
Kocer, Derya; Sarıguzel, Fatma M; Karakukcu, Cıgdem
2014-08-01
The microscopic analysis of urine is essential for the diagnosis of patients with urinary tract infections. Quantitative urine culture is the 'gold standard' method for definitive diagnosis of urinary-tract infections, but it is labor-intensive, time consuming, and does not provide the same-day results. The aim of this study was to evaluate the analytical and diagnostic performance of the FUS200 (Changchun Dirui Industry, China), a new urine sedimentation analyzer in comparison to urine culture as the reference method. We evaluated 1000 urine samples, submitted for culture and urine analysis with a preliminary diagnosis of urinary-tract infection. Cut-off values for the FUS200 were determined by comparing the results with urine cultures. The cut-off values by the receiver operating characteristic (ROC) curve technique, sensitivity, and specificity were calculated for bacteria and white blood cells (WBCs). Among the 1000 urine specimens submitted for culture, 637 cultures (63.7%) were negative, and 363 were (36.3%) positive. The best cut-off values obtained from ROC analysis were 16/μL for bacteriuria (sensitivity: 82.3%, specificity: 58%), and 34/μL for WBCs (sensitivity: 72.3%, specificity: 65.2%). The area under the curve (AUC) for the bacteria and WBCs count were 0.71 (95% CI: 0.67-0.74) and, 0.72 (95% CI: 0.69-0.76) respectively. The most important requirement of a rapid diagnostic screening test is sensitivity, and, in this perspective, an unsatisfactory sensitivity by using bacteria recognition and quantification performed by the FUS200 analyzer has been observed. After further technical improvements in particle recognition and laboratory personnel training, the FUS200 might show better results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Shunli; Fu, Li; Gan, Wei
2016-01-21
In this report we show that the ability to measure the sub-1 cm -1 resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra (HR-BB-SFG-VS) of the –CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4’-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows for the first time the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral lineshapes in detail. The difference of the full width at half maxima (FWHM) of the imaginary and intensity SFG-VS spectra of the same vibrational mode is the signature of the Voigtmore » lineshape and it measures the relative contribution to the overall lineshape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ±0.02 cm -1 peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm -1 and 21.6 ± 0.4 cm -1, respectively, for the –CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm -1 agrees quantitatively with a Voigt lineshape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm -1 and a inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm -1. These results shed new lights on the understanding and interpretation of the lineshapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.« less
Chen, Shun-Li; Fu, Li; Gan, Wei; Wang, Hong-Fei
2016-01-21
In this report, we show that the ability to measure the sub-1 cm(-1) resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra of the -CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4'-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral line shapes in detail. The difference of the full width at half maximum (FWHM) of the imaginary and intensity sum-frequency generation vibrational spectroscopy spectra of the same vibrational mode is the signature of the Voigt line shape and it measures the relative contribution to the overall line shape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ± 0.02 cm(-1) peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm(-1) and 21.6 ± 0.4 cm(-1), respectively, for the -CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm(-1) agrees quantitatively with a Voigt line shape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm(-1) and an inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm(-1). These results shed new lights on the understanding and interpretation of the line shapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.
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.
García, Carlos J; García-Villalba, Rocío; Gil, María I; Tomas-Barberan, Francisco A
2017-06-07
Enzymatic browning is one of the main causes of quality loss in lettuce as a prepared and ready-to-eat cut salad. An untargeted metabolomics approach using UPLC-ESI-QTOF-MS was performed to explain the wound response of lettuce after cutting and to identify the metabolites responsible of browning. Two cultivars of Romaine lettuce with different browning susceptibilities were studied at short time intervals after cutting. From the total 5975 entities obtained from the raw data after alignment, filtration reduced the number of features to 2959, and the statistical analysis found that only 1132 entities were significantly different. Principal component analysis (PCA) clearly showed that these samples grouped according to cultivar and time after cutting. From those, only 15 metabolites belonging to lysophospholipids, oxylipin/jasmonate metabolites, and phenolic compounds were able to explain the browning process. These selected metabolites showed different trends after cutting; some decreased rapidly, others increased but decreased thereafter, whereas others increased during the whole period of storage. In general, the fast-browning cultivar showed a faster wound response and a higher raw intensity of some key metabolites than the slow-browning one. Just after cutting, the fast-browning cultivar contained 11 of the 15 browning-associated metabolites, whereas the slow-browning cultivar only had 5 of them. These metabolites could be used as biomarkers in breeding programs for the selection of lettuce cultivars with lower browning potential for fresh-cut applications.
Selective preparation of hard dental tissue: classical and laser treatments comparison
NASA Astrophysics Data System (ADS)
Dostálova, Tat'jana; Jelínkova, Helena; Němec, Michal; Koranda, Petr; Miyagi, Mitsunobu; Iwai, Katsumasa; Shi, Yi-Wei; Matsuura, Yuji
2006-02-01
For the purpose of micro-selective preparation which is part of the modern dentistry four various methods were examined: ablation by Er:YAG laser radiation (free-running or Q-switching regime), preparation of tissues by ultrasonic round ball tip, and by the classical dental drilling machine using diamond round bur. In the case of Er:YAG laser application the interaction energy 40 mJ in pulse of 200 us yielding to the interaction intensity 62 kW/cm2, and 20 mJ in pulse of 100 ns yielding to the interaction intensity 62 MW/cm2 was used for the case of free running, and Q-switch regime, respectively. For comparisson with the classical methods the ultrasound preparation tip (Sonixflex cariex TC, D - Sonicsys micro) and dental driller together with usual preparation burrs and standard handpiece were used. For the interaction experiment the samples of extracted human teeth and ebony cut into longitudinal sections and polished were used. The thickness of the prepared samples ranged from 5 to 7 mm. The methods were compared from the point of prepared cavity shape (SEM), inner surface, and possibility of selective removal of carries. The composite filling material was used to reconstruct the cavities. The dye penetrating analysis was performed.
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.
Hip and Wrist Accelerometer Algorithms for Free-Living Behavior Classification.
Ellis, Katherine; Kerr, Jacqueline; Godbole, Suneeta; Staudenmayer, John; Lanckriet, Gert
2016-05-01
Accelerometers are a valuable tool for objective measurement of physical activity (PA). Wrist-worn devices may improve compliance over standard hip placement, but more research is needed to evaluate their validity for measuring PA in free-living settings. Traditional cut-point methods for accelerometers can be inaccurate and need testing in free living with wrist-worn devices. In this study, we developed and tested the performance of machine learning (ML) algorithms for classifying PA types from both hip and wrist accelerometer data. Forty overweight or obese women (mean age = 55.2 ± 15.3 yr; BMI = 32.0 ± 3.7) wore two ActiGraph GT3X+ accelerometers (right hip, nondominant wrist; ActiGraph, Pensacola, FL) for seven free-living days. Wearable cameras captured ground truth activity labels. A classifier consisting of a random forest and hidden Markov model classified the accelerometer data into four activities (sitting, standing, walking/running, and riding in a vehicle). Free-living wrist and hip ML classifiers were compared with each other, with traditional accelerometer cut points, and with an algorithm developed in a laboratory setting. The ML classifier obtained average values of 89.4% and 84.6% balanced accuracy over the four activities using the hip and wrist accelerometer, respectively. In our data set with average values of 28.4 min of walking or running per day, the ML classifier predicted average values of 28.5 and 24.5 min of walking or running using the hip and wrist accelerometer, respectively. Intensity-based cut points and the laboratory algorithm significantly underestimated walking minutes. Our results demonstrate the superior performance of our PA-type classification algorithm, particularly in comparison with traditional cut points. Although the hip algorithm performed better, additional compliance achieved with wrist devices might justify using a slightly lower performing algorithm.
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.
Breast mass segmentation in mammography using plane fitting and dynamic programming.
Song, Enmin; Jiang, Luan; Jin, Renchao; Zhang, Lin; Yuan, Yuan; Li, Qiang
2009-07-01
Segmentation is an important and challenging task in a computer-aided diagnosis (CAD) system. Accurate segmentation could improve the accuracy in lesion detection and characterization. The objective of this study is to develop and test a new segmentation method that aims at improving the performance level of breast mass segmentation in mammography, which could be used to provide accurate features for classification. This automated segmentation method consists of two main steps and combines the edge gradient, the pixel intensity, as well as the shape characteristics of the lesions to achieve good segmentation results. First, a plane fitting method was applied to a background-trend corrected region-of-interest (ROI) of a mass to obtain the edge candidate points. Second, dynamic programming technique was used to find the "optimal" contour of the mass from the edge candidate points. Area-based similarity measures based on the radiologist's manually marked annotation and the segmented region were employed as criteria to evaluate the performance level of the segmentation method. With the evaluation criteria, the new method was compared with 1) the dynamic programming method developed by Timp and Karssemeijer, and 2) the normalized cut segmentation method, based on 337 ROIs extracted from a publicly available image database. The experimental results indicate that our segmentation method can achieve a higher performance level than the other two methods, and the improvements in segmentation performance level were statistically significant. For instance, the mean overlap percentage for the new algorithm was 0.71, whereas those for Timp's dynamic programming method and the normalized cut segmentation method were 0.63 (P < .001) and 0.61 (P < .001), respectively. We developed a new segmentation method by use of plane fitting and dynamic programming, which achieved a relatively high performance level. The new segmentation method would be useful for improving the accuracy of computerized detection and classification of breast cancer in mammography.
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.
Laser processing of thin films for industrial packaging
NASA Astrophysics Data System (ADS)
Sozzi, Michele; Lutey, Adrian H. A.; Cucinotta, Annamaria; Selleri, Stefano; Molari, Pier Gabriele
2014-05-01
Single layer thin-film materials such as aluminum, polyethylene, polypropylene, and their multi-layer combinations such as aluminum-paper have been exposed to different laser radiation. A wide number of samples have been processed with 10 - 12.5 ns IR and Green, and 500 - 800 ps IR laser radiation at different translating speeds ranging from 50 mm/s to 1 m/s. High quality incisions have been obtained for all tested materials within the experimental conditions. The presented results provide the necessary parameters for an efficient cut and processing of the tested materials, for the employment of pulsed laser sources in the packaging industry, allowing the laser to prevail in lieu of more costly and energy intensive methods.
NASA Astrophysics Data System (ADS)
Vícha, Jakub; Trávníček, Petr; Nosek, Dalibor; Ebr, Jan
2015-09-01
We consider a hypothetical observatory of ultra-high energy cosmic rays consisting of two surface detector arrays that measure independently electromagnetic and muon signals induced by air showers. Using the constant intensity cut method, sets of events ordered according to each of both signal sizes are compared giving the number of matched events. Based on its dependence on the zenith angle, a parameter sensitive to the dispersion of the distribution of the logarithmic mass of cosmic rays is introduced. The results obtained using two post-LHC models of hadronic interactions are very similar and indicate a weak dependence on details of these interactions.
Lactate clearance cut off for early mortality prediction in adult sepsis and septic shock patients
NASA Astrophysics Data System (ADS)
Sinto, R.; Widodo, D.; Pohan, H. T.
2018-03-01
Previous lactate clearance cut off for early mortality prediction in sepsis and septic shock patient was determined by consensus from small sample size-study. We investigated the best lactate clearance cut off and its ability to predict early mortality in sepsis and septic shock patients. This cohort study was conducted in Intensive Care Unit of CiptoMangunkusumo Hospital in 2013. Patients’ lactate clearance and eight other resuscitationendpoints were recorded, and theoutcome was observed during the first 120 hours. The clearance cut off was determined using receiver operating characteristic (ROC) analysis, and its ability was investigated with Cox’s proportional hazard regression analysis using other resuscitation endpoints as confounders. Total of 268 subjects was included, of whom 70 (26.11%) subjects died within the first 120 hours. The area under ROC of lactate clearance to predict early mortality was 0.78 (95% % confidence interval [CI] 0.71-0.84) with best cut off was <7.5% (sensitivity and specificity 88.99% and 81.4% respectively). Compared with group achieving lactate clearance target, group not achieving lactate clearance target had to increase early mortality risk (adjusted hazard ratio 13.42; 95%CI 7.19-25.07). In conclusion, the best lactate clearance cut off as anearly mortality predictor in sepsis and septic shock patients is 7.5%.
ERIC Educational Resources Information Center
Lin, Jie
2006-01-01
The Bookmark standard-setting procedure was developed to address the perceived problems with the most popular method for setting cut-scores: the Angoff procedure (Angoff, 1971). The purposes of this article are to review the Bookmark procedure and evaluate it in terms of Berk's (1986) criteria for evaluating cut-score setting methods. The…
Method and apparatus for suppressing regenerative instability and related chatter in machine tools
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.
Accurate segmenting of cervical tumors in PET imaging based on similarity between adjacent slices.
Chen, Liyuan; Shen, Chenyang; Zhou, Zhiguo; Maquilan, Genevieve; Thomas, Kimberly; Folkert, Michael R; Albuquerque, Kevin; Wang, Jing
2018-06-01
Because in PET imaging cervical tumors are close to the bladder with high capacity for the secreted 18 FDG tracer, conventional intensity-based segmentation methods often misclassify the bladder as a tumor. Based on the observation that tumor position and area do not change dramatically from slice to slice, we propose a two-stage scheme that facilitates segmentation. In the first stage, we used a graph-cut based algorithm to obtain initial contouring of the tumor based on local similarity information between voxels; this was achieved through manual contouring of the cervical tumor on one slice. In the second stage, initial tumor contours were fine-tuned to more accurate segmentation by incorporating similarity information on tumor shape and position among adjacent slices, according to an intensity-spatial-distance map. Experimental results illustrate that the proposed two-stage algorithm provides a more effective approach to segmenting cervical tumors in 3D 18 FDG PET images than the benchmarks used for comparison. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zou, X. J.; Zheng, G. G.; Chen, Y. Y.; Xu, L. H.; Lai, M.
2018-04-01
A multi-band absorber constructed from prism-incorporated one-dimensional photonic crystal (1D-PhC) containing graphene defects is achieved theoretically in the visible and near-infrared (vis-NIR) spectral range. By means of the transfer matrix method (TMM), the effect of structural parameters on the optical response of the structure has been investigated. It is possible to achieve multi-peak and complete optical absorption. The simulations reveal that the light intensity is enhanced at the graphene plane, and the resonant wavelength and the absorption intensity can also be tuned by tilting the incidence angle of the impinging light. In particular, multiple graphene sheets are embedded in the arrays, without any demand of manufacture process to cut them into periodic patterns. The proposed concept can be extended to other two-dimensional (2D) materials and engineered for promising applications, including selective or multiplex filters, multiple channel sensors, and photodetectors.
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.
Trujillo, Francisco Javier; Sevilla, Lorenzo; Marcos, Mariano
2017-01-01
In this work, the study of the influence of cutting parameters (cutting speed, feed, and depth of cut) on the tool wear used in in the dry turning of cylindrical bars of the UNS A97075 (Al-Zn) alloy, has been analyzed. In addition, a study of the physicochemical mechanisms of the secondary adhesion wear has been carried out. The behavior of this alloy, from the point of view of tool wear, has been compared to similar aeronautical aluminum alloys, such as the UNS A92024 (Al-Cu) alloy and UNS A97050 (Al-Zn) alloy. Furthermore, a first approach to the measurement of the 2D surface of the adhered material on the rake face of the tool has been conducted. Finally, a parametric model has been developed from the experimental results. This model allows predicting the intensity of the secondary adhesion wear as a function of the cutting parameters applied. PMID:28772510
Intense laser beams; Proceedings of the Meeting, Los Angeles, CA, Jan. 23, 24, 1992
NASA Technical Reports Server (NTRS)
Wade, Richard C. (Editor); Ulrich, Peter B. (Editor)
1992-01-01
Various papers on intense laser beams are presented. Individual topics addressed include: novel methods of copper vapor laser excitation, UCLA IR FEL, lasing characteristics of a large-bore copper vapor laser (CVL), copper density measurement of a large-bore CVL, high-power XeCl excimer laser, solid state direct-drive circuit for pumping gas lasers, united energy model for FELs, intensity and frequency instabilities in double-mode CO2 lasers, comparison of output power stabilities of CO and CO2 lasers, increasing efficiency of sealed-off CO lasers, thermal effects in singlet delta oxygen generation, optical extraction from the chemical oxygen-iodine laser medium, generation and laser diagnostic analysis of bismuth fluoride. Also discussed are: high-Q resonator design for an HF overtone chemical lasers, improved coatings for HF overtone lasers, scaled atmospheric blooming experiment, simulation on producing conjugate field using deformable mirrors, paraxial theory of amplitude correction, potential capabilities of adaptive optical systems in the atmosphere, power beaming research at NASA, system evaluations of laser power beaming options, performance projections for laser beam power to space, independent assessment of laser power beaming options, removal of atmospheric CFCs by lasers, efficiency of vaporization cutting by CVL.
NASA Astrophysics Data System (ADS)
Agarwal Mishra, Rekha; Mishra, Rajesh Kumar
2016-07-01
Propagation of cosmic rays to and inside the heliosphere, encounter an outward moving solar wind with cyclic magnetic field fluctuation and turbulence, causing convection and diffusion in the heliosphere. Cosmic ray counts from the ground ground-based neutron monitors at different cut of rigidity show intensity changes, which are anti-correlated with sunspot numbers. They also lose energy as they propagate towards the Earth and experience various types of modulations due to different solar activity indices. In this work, we study the first three harmonics of cosmic ray intensity on geo-magnetically quiet days over the period 1965-2014 for Beijing, Moscow and Tokyo neutron monitoring stations located at different cut off rigidity. The amplitude of first harmonic remains high for low cutoff rigidity as compared to high cutoff rigidity on quiet days. The diurnal amplitude significantly decreases during solar activity minimum years. The diurnal time of maximum significantly shifts to an earlier time as compared to the corotational direction having different cutoff rigidities. The time of maximum for first harmonic significantly shifts towards later hours and for second harmonic it shifts towards earlier hours at low cutoff rigidity station as compared to the high cut off rigidity station on quiet days. The amplitude of second/third harmonics shows a good positive correlation with solar wind velocity, while the others (i.e. amplitude and phase) have no significant correlation on quiet days. The amplitude and direction of the anisotropy on quiet days does not show any significant dependence on high-speed solar wind streams for these neutron monitoring stations of different cutoff rigidity threshold. Keywords: cosmic ray, cut off rigidity, quiet days, harmonics, amplitude, phase.
A supervoxel-based segmentation method for prostate MR images.
Tian, Zhiqiang; Liu, Lizhi; Zhang, Zhenfeng; Xue, Jianru; Fei, Baowei
2017-02-01
Segmentation of the prostate on MR images has many applications in prostate cancer management. In this work, we propose a supervoxel-based segmentation method for prostate MR images. A supervoxel is a set of pixels that have similar intensities, locations, and textures in a 3D image volume. The prostate segmentation problem is considered as assigning a binary label to each supervoxel, which is either the prostate or background. A supervoxel-based energy function with data and smoothness terms is used to model the label. The data term estimates the likelihood of a supervoxel belonging to the prostate by using a supervoxel-based shape feature. The geometric relationship between two neighboring supervoxels is used to build the smoothness term. The 3D graph cut is used to minimize the energy function to get the labels of the supervoxels, which yields the prostate segmentation. A 3D active contour model is then used to get a smooth surface by using the output of the graph cut as an initialization. The performance of the proposed algorithm was evaluated on 30 in-house MR image data and PROMISE12 dataset. The mean Dice similarity coefficients are 87.2 ± 2.3% and 88.2 ± 2.8% for our 30 in-house MR volumes and the PROMISE12 dataset, respectively. The proposed segmentation method yields a satisfactory result for prostate MR images. The proposed supervoxel-based method can accurately segment prostate MR images and can have a variety of application in prostate cancer diagnosis and therapy. © 2016 American Association of Physicists in Medicine.
Rockwell, Cara A.; Guariguata, Manuel R.; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José
2015-01-01
Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù. PMID:26271042
Rockwell, Cara A; Guariguata, Manuel R; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Quenta Hancco, Roger; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José
2015-01-01
Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world's most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1-2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù.
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.
Brain Damage Treated with Non Proven Intensive Training 2003-2011: A Norwegian Cost Analysis
Norum, Jan; Ramsvik, Arnborg; Tjeldnes, Knut
2012-01-01
Objectives: There has been an increased request for intensive training and rehabilitation of patients with brain damage in Norway. These programs are demanding with regard to personnel, travelling, time and economic resources. We aimed to indicate cost and gain to make these programs cost-effective. Methods: A retrospective study included all patients referred to the Northern Norway Regional Health Authority (NNRHA) trust during the nine years period 2003-2011. All referrals to the NNRHA trust for the economic coverage of foreign based rehabilitation or habilitation programs (The Advanced Bio-Mechanical Rehabilitation (ABR), Institutes of Achievement of Human Potential program (IAHP) (Doman method), Family Hope Center (FHC) program and the Kozijavkin method) were included. 17 patients were detected and 15 fulfilled the inclusion criteria for funding. Median age was 8 years (1-31 years). Cost from the specialist health care point of view was calculated. A cut-off limit of €57,000/quality adjusted life year (QALY) and a 4% discount rate was employed. Results: The undiscounted cost per patient enrolled was calculated €133,210 (discounted €121,348). To make these therapies cost effective, a total of at least 2.13 QALYs (2.34 undiscounted QALYs) must be gained per patient enrolled. Such a gain could not be indicated and we doubt it is achievable. Conclusion: Non-proven intensive training programs for patients with brain damage are costly. As long as their effect has not been documented, health care services should not spend resources on these programs outside clinical trials. PMID:23121754
Pimentel, Marcio Fernandes; Soares, Marcelo José Ferreira; Murad Junior, Jamil Alli; de Oliveira, Marcos Aurelio Barboza; Faria, Fernanda Luiza; Faveri, Vinicius Zani; Iano, Yuzo; Guido, Rodrigo Capobianco
2017-01-01
Objective To test the capacity of the Logistic CASUS Score on the second postoperative day, the total serum bilirubin dosage on the second postoperative day and the extracorporeal circulation time, as possible predictive factors of long-term stay in Intensive Care Unit after cardiac surgery. Methods Eight-two patients submitted to cardiac surgery with extracorporeal circulation were selected. The Logistic CASUS Score on the second postoperative day was calculated and bilirubin dosage on the second postoperative day was measured. The extracorporeal circulation time was also registered. Patients were divided into two groups: Group A, those who were discharged up to the second day of postoperative care; Group B, those who were discharged after the second day of postoperative care. Results In this study, 40 cases were listed in Group A and 42 cases in Group B. The mean extracorporeal circulation time was 83.9±29.4 min in Group A and 95.8±29.31 min in Group B. Extracorporeal circulation time was not significant in this study (P=0.0735). The level of P significance of bilirubin dosage on the second postoperative day was 0.0003 and an area under the ROC curve of 0.708 with a cut-off point at 0.51 mg/dl was registered. The level of P significance of Logistic CASUS Score on the second postoperative day was 0.0001 and an area under the ROC curve of 0.723 with a cut-off point at 0.40% was registered. Conclusion The Logistic CASUS Score on the second postoperative day has shown to be better than the bilirubin dosage on the second postoperative day as a predictive tool for calculating the length of stay in intensive care unit during the postoperative care period of patients. Notwithstanding, extracorporeal circulation time has failed to prove itself as an efficient tool to predict an extended length of stay in intensive care unit. PMID:29211215
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...
Malanson, Katherine; Jacque, Berri; Faux, Russell; Meiri, Karina F.
2014-01-01
This small-scale comparison case study evaluates the impact of an innovative approach to teacher professional development designed to promote implementation of a novel cutting edge high school neurological disorders curriculum. ‘Modeling for Fidelity’ (MFF) centers on an extended mentor relationship between teachers and biomedical scientists carried out in a virtual format in conjunction with extensive online educative materials. Four teachers from different diverse high schools in Massachusetts and Ohio who experienced MFF contextualized to a 6-week Neurological Disorders curriculum with the same science mentor were compared to a teacher who had experienced an intensive in-person professional development contextualized to the same curriculum with the same mentor. Fidelity of implementation was measured directly using an established metric and indirectly via student performance. The results show that teachers valued MFF, particularly the mentor relationship and were able to use it effectively to ensure critical components of the learning objectives were preserved. Moreover their students performed equivalently to those whose teacher had experienced intensive in-person professional development. Participants in all school settings demonstrated large (Cohen's d>2.0) and significant (p<0.0001 per-post) changes in conceptual knowledge as well as self-efficacy towards learning about neurological disorders (Cohen's d>1.5, p<0.0001 pre-post). The data demonstrates that the virtual mentorship format in conjunction with extensive online educative materials is an effective method of developing extended interactions between biomedical scientists and teachers that are scalable and not geographically constrained, facilitating teacher implementation of novel cutting-edge curricula. PMID:25551645
Malanson, Katherine; Jacque, Berri; Faux, Russell; Meiri, Karina F
2014-01-01
This small-scale comparison case study evaluates the impact of an innovative approach to teacher professional development designed to promote implementation of a novel cutting edge high school neurological disorders curriculum. 'Modeling for Fidelity' (MFF) centers on an extended mentor relationship between teachers and biomedical scientists carried out in a virtual format in conjunction with extensive online educative materials. Four teachers from different diverse high schools in Massachusetts and Ohio who experienced MFF contextualized to a 6-week Neurological Disorders curriculum with the same science mentor were compared to a teacher who had experienced an intensive in-person professional development contextualized to the same curriculum with the same mentor. Fidelity of implementation was measured directly using an established metric and indirectly via student performance. The results show that teachers valued MFF, particularly the mentor relationship and were able to use it effectively to ensure critical components of the learning objectives were preserved. Moreover their students performed equivalently to those whose teacher had experienced intensive in-person professional development. Participants in all school settings demonstrated large (Cohen's d>2.0) and significant (p<0.0001 per-post) changes in conceptual knowledge as well as self-efficacy towards learning about neurological disorders (Cohen's d>1.5, p<0.0001 pre-post). The data demonstrates that the virtual mentorship format in conjunction with extensive online educative materials is an effective method of developing extended interactions between biomedical scientists and teachers that are scalable and not geographically constrained, facilitating teacher implementation of novel cutting-edge curricula.
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...
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.
Dumais, Daniel; Prévost, Marcel
2008-08-01
We investigated ecophysiological and growth responses of short (0.4 to 1.3 m in height) advance regeneration of red spruce (Picea rubens Sarg.) and balsam fir (Abies balsamea L.) six years after removal of 0, 40, 50, 60 and 100% of the overstory basal area (BA) in two yellow birch-conifer stands. Partial cuts significantly increased stomatal conductance of red spruce only. Light-saturated photosynthesis (leaf-area basis) of both species increased with BA removal, but unlike red spruce, specific leaf area (SLA) of balsam fir decreased with increased cutting intensity. Partial cuts appreciably increased the concentration of N and Ca in red spruce and balsam fir foliage, respectively, and resulted in decreased foliar concentrations of K in red spruce and Mg in balsam fir. The height and lateral growth of both species increased with BA removal, although partial cuts were more beneficial to balsam fir. The data suggest that short advance regeneration of red spruce and balsam fir can coexist under partial overstory conditions, but balsam fir has physiological characteristics and a capacity for morphological adjustment (SLA) that places it at an advantage when in competition with red spruce.
Silveira, Ana C; Aguayo, Encarna; Artés, Francisco
2013-12-01
Melons (Cucumis melo L.) are widely cultivated in Mediterranean countries. For fresh-cut melon elaboration, factors such as type of cultivar and cut have a significant impact on final product quality. The quality parameters from long, medium and short shelf-life Galia melon cultivars, cut into different shapes such as slices, trapezoids and cylinders and stored up to 10 days at 5 °C, were evaluated in order to learn the suitability of these cultivars and type of cut for minimal processing. In general, long-life melon cultivar had a low respiration rate and ethylene emissions, and high tissue firmness, but low levels of glucose, fructose, vitamin C and flavor rating by consumers. However, despite having higher metabolic activity and susceptibility to microbial spoilage, the short shelf-life cultivar melon had higher firmness retention. This cultivar was characterized by its richness in glucose, fructose and vitamin C, and its sensory quality (flavor) was highly valued. In general, the medium cultivar had an intermediate behavior between long and short cultivars but without their positive attributes. As a consequence of the most intense damage, the cylindrical shape had higher metabolic activity, susceptibility to microbial spoilage and reduced appearance. In the long and medium-life cultivars studied, low flavor was the limiting factor to extend the shelf-life of fresh-cut melon while for the short-life cultivar the limiting factor was its susceptibility to bacterial growth. Cut types such as cylinders should be avoided. © 2013 Society of Chemical Industry.
Klopotek, Yvonne; Haensch, Klaus-Thomas; Hause, Bettina; Hajirezaei, Mohammad-Reza; Druege, Uwe
2010-05-01
The effect of temporary dark exposure on adventitious root formation (ARF) in Petuniaxhybrida 'Mitchell' cuttings was investigated. Histological and metabolic changes in the cuttings during the dark treatment and subsequent rooting in the light were recorded. Excised cuttings were exposed to the dark for seven days at 10 degrees C followed by a nine-day rooting period in perlite or were rooted immediately for 16 days in a climate chamber at 22/20 degrees C (day/night) and a photosynthetic photon flux density (PPFD) of 100micromolm(-2)s(-1). Dark exposure prior to rooting increased, accelerated and synchronized ARF. The rooting period was reduced from 16 days (non-treated cuttings) to 9 days (treated cuttings). Under optimum conditions, despite the reduced rooting period, dark-exposed cuttings produced a higher number and length of roots than non-treated cuttings. An increase in temperature to 20 degrees C during the dark treatment or extending the cold dark exposure to 14 days caused a similar enhancement of root development compared to non-treated cuttings. Root meristem formation had already started during the dark treatment and was enhanced during the subsequent rooting period. Levels of soluble sugars (glucose, fructose and sucrose) and starch in leaf and basal stem tissues significantly decreased during the seven days of dark exposure. This depletion was, however, compensated during rooting after 6 and 24h for soluble sugars in leaves and the basal stem, respectively, whereas the sucrose level in the basal stem was already increased at 6h. The association of higher carbohydrate levels with improved rooting in previously dark-exposed versus non-treated cuttings indicates that increased post-darkness carbohydrate availability and allocation towards the stem base contribute to ARF under the influence of dark treatment and provide energy for cell growth subject to a rising sink intensity in the base of the cutting. Copyright 2009 Elsevier GmbH. All rights reserved.
A composite lithology log while drilling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tannenbaum, E.; Sutcliffe, B.; Franks, A.
A new method for producing a computerized composite lithology log (CLL) while drilling by integrating MWD (measurement while drilling) and surface data is described. At present, lithology logs are produced at the well site by mud loggers. They provide basic description and relative amounts of lithologies. Major difficulties are encountered in relating the cuttings to their original formations due to mixing in the drilling mud while transporting to the surface, sloughing shales, flawed sampling, etc. This results in a poor control on the stratigraphic sequence and on the depth of formation boundaries. A composite log can be produced after drillingmore » this additional inputs such as wireline, petrography, and paleontology. This process is labor intensive and expensive. The CLL integrates three types of data (MWD mechanical, MWD geophysical, and surface cuttings) acquired during drilling, in three time stages: (1) Real Time. MWD drilling mechanical data including the rate of penetration and the downhole torque. This stage would provide bed boundaries and some inferred lithology. This would assist the driller with immediate drilling decisions and determine formation tops for coring, casing point, and correlation. (2) MWD Time. Recomputation of the above by adding MWD geophysical data (gamma-ray, resistivity, neutron-density). This stage would upgrade the lithology inference, and give higher resolution to bed boundaries, (3) Lag Time. Detailed analysis of surface cuttings to confirm the inferred lithologies. This last input results in a high-quality CLL with accurate lithologies and bed boundaries.« less
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
Silvicultural rehabilitation of cutover mixedwood stands
Laura S. Kenefic; Mohammad Bataineh; Jeremy S. Wilson; John C. Brissette; Ralph D. Nyland
2014-01-01
We investigated rehabilitation of mixedwood stands degraded by exploitative cutting on the Penobscot Experimental Forest in Maine. Three precommercial rehabilitation treatments were applied: control (no rehabilitation), moderate rehabilitation (crop tree release [CTR]), and intensive rehabilitation (CTR, timber stand improvement [TSI], and red spruce fill planting)....
Aorta and pulmonary artery segmentation using optimal surface graph cuts in non-contrast CT
NASA Astrophysics Data System (ADS)
Sedghi Gamechi, Zahra; Arias-Lorza, Andres M.; Pedersen, Jesper Holst; de Bruijne, Marleen
2018-03-01
Accurate measurements of the size and shape of the aorta and pulmonary arteries are important as risk factors for cardiovascular diseases, and for Chronicle Obstacle Pulmonary Disease (COPD).1 The aim of this paper is to propose an automated method for segmenting the aorta and pulmonary arteries in low-dose non-ECGgated non-contrast CT scans. Low contrast and the high noise level make the automatic segmentation in such images a challenging task. In the proposed method, first, a minimum cost path tracking algorithm traces the centerline between user-defined seed points. The cost function is based on a multi-directional medialness filter and a lumen intensity similarity metric. The vessel radius is also estimated from the medialness filter. The extracted centerlines are then smoothed and dilated non-uniformly according to the extracted local vessel radius and subsequently used as initialization for a graph-cut segmentation. The algorithm is evaluated on 225 low-dose non-ECG-gated non-contrast CT scans from a lung cancer screening trial. Quantitatively analyzing 25 scans with full manual annotations, we obtain a dice overlap of 0.94+/-0.01 for the aorta and 0.92+/-0.01 for pulmonary arteries. Qualitative validation by visual inspection on 200 scans shows successful segmentation in 93% of all cases for the aorta and 94% for pulmonary arteries.
Dai, Jianrong; Que, William
2004-12-07
This paper introduces a method to simultaneously minimize the leaf travel distance and the tongue-and-groove effect for IMRT leaf sequences to be delivered in segmental mode. The basic idea is to add a large enough number of openings through cutting or splitting existing openings for those leaf pairs with openings fewer than the number of segments so that all leaf pairs have the same number of openings. The cutting positions are optimally determined with a simulated annealing technique called adaptive simulated annealing. The optimization goal is set to minimize the weighted summation of the leaf travel distance and tongue-and-groove effect. Its performance was evaluated with 19 beams from three clinical cases; one brain, one head-and-neck and one prostate case. The results show that it can reduce the leaf travel distance and (or) tongue-and-groove effect; the reduction of the leaf travel distance reaches its maximum of about 50% when minimized alone; the reduction of the tongue-and-groove reaches its maximum of about 70% when minimized alone. The maximum reduction in the leaf travel distance translates to a 1 to 2 min reduction in treatment delivery time per fraction, depending on leaf speed. If the method is implemented clinically, it could result in significant savings in treatment delivery time, and also result in significant reduction in the wear-and-tear of MLC mechanics.
Novel methods for measuring afterglow in developmental scintillators for X-ray and neutron detection
NASA Astrophysics Data System (ADS)
Bartle, C. M.; Edgar, A.; Dixie, L.; Varoy, C.; Piltz, R.; Buchanan, S.; Rutherford, K.
2011-09-01
In this paper we discuss two novel methods of measuring afterglow in scintillators. One method is designed for X-ray detection and the other for neutron detection applications. In the first method a commercial fan-beam scanner of basic design similar to those seen at airports is used to deliver a typically 12 ms long X-ray pulse to a scintillator by passing the test equipment through the scanner on the conveyor belt. In the second method the thermal neutron beam from a research reactor is incident on the scintillator. The beam is cut-off in about 1 ms using a 10B impregnated aluminum pneumatic shutter, and the afterglow is recorded on a dual range storage oscilloscope to capture both the steady state intensity and the weak decay. We describe these measurement methods and the results obtained for a range of developmental ceramic and glass scintillators, as well as some standard scintillators such as NaI(Tl), LiI(Eu) and the plastic scintillator NE102A. Preliminary modeling of the afterglow is presented.
Designing an optimal software intensive system acquisition: A game theoretic approach
NASA Astrophysics Data System (ADS)
Buettner, Douglas John
The development of schedule-constrained software-intensive space systems is challenging. Case study data from national security space programs developed at the U.S. Air Force Space and Missile Systems Center (USAF SMC) provide evidence of the strong desire by contractors to skip or severely reduce software development design and early defect detection methods in these schedule-constrained environments. The research findings suggest recommendations to fully address these issues at numerous levels. However, the observations lead us to investigate modeling and theoretical methods to fundamentally understand what motivated this behavior in the first place. As a result, Madachy's inspection-based system dynamics model is modified to include unit testing and an integration test feedback loop. This Modified Madachy Model (MMM) is used as a tool to investigate the consequences of this behavior on the observed defect dynamics for two remarkably different case study software projects. Latin Hypercube sampling of the MMM with sample distributions for quality, schedule and cost-driven strategies demonstrate that the higher cost and effort quality-driven strategies provide consistently better schedule performance than the schedule-driven up-front effort-reduction strategies. Game theory reasoning for schedule-driven engineers cutting corners on inspections and unit testing is based on the case study evidence and Austin's agency model to describe the observed phenomena. Game theory concepts are then used to argue that the source of the problem and hence the solution to developers cutting corners on quality for schedule-driven system acquisitions ultimately lies with the government. The game theory arguments also lead to the suggestion that the use of a multi-player dynamic Nash bargaining game provides a solution for our observed lack of quality game between the government (the acquirer) and "large-corporation" software developers. A note is provided that argues this multi-player dynamic Nash bargaining game also provides the solution to Freeman Dyson's problem, for a way to place a label of good or bad on systems.
A calibration protocol for population-specific accelerometer cut-points in children.
Mackintosh, Kelly A; Fairclough, Stuart J; Stratton, Gareth; Ridgers, Nicola D
2012-01-01
To test a field-based protocol using intermittent activities representative of children's physical activity behaviours, to generate behaviourally valid, population-specific accelerometer cut-points for sedentary behaviour, moderate, and vigorous physical activity. Twenty-eight children (46% boys) aged 10-11 years wore a hip-mounted uniaxial GT1M ActiGraph and engaged in 6 activities representative of children's play. A validated direct observation protocol was used as the criterion measure of physical activity. Receiver Operating Characteristics (ROC) curve analyses were conducted with four semi-structured activities to determine the accelerometer cut-points. To examine classification differences, cut-points were cross-validated with free-play and DVD viewing activities. Cut-points of ≤ 372, >2160 and >4806 counts • min(-1) representing sedentary, moderate and vigorous intensity thresholds, respectively, provided the optimal balance between the related needs for sensitivity (accurately detecting activity) and specificity (limiting misclassification of the activity). Cross-validation data demonstrated that these values yielded the best overall kappa scores (0.97; 0.71; 0.62), and a high classification agreement (98.6%; 89.0%; 87.2%), respectively. Specificity values of 96-97% showed that the developed cut-points accurately detected physical activity, and sensitivity values (89-99%) indicated that minutes of activity were seldom incorrectly classified as inactivity. The development of an inexpensive and replicable field-based protocol to generate behaviourally valid and population-specific accelerometer cut-points may improve the classification of physical activity levels in children, which could enhance subsequent intervention and observational studies.
Experiences in implementing uHTS--cutting edge technology meets the real world.
Gribbon, Philip; Schaertl, Sabine; Wickenden, Malcolm; Williams, Gareth; Grimley, Rachel; Stuhmeier, Frank; Preckel, Hartwig; Eggeling, Christian; Kraemer, Joachim; Everett, Jeremy; Keighley, Wilma W; Sewing, Andreas
2004-01-01
Driven by growing corporate compound files, the demands of target biology, and attempts to cut cost, the number of solutions to HTS has spiralled. In quick succession new assay technologies and screening platforms are appearing on the market, with the promise of screening faster than ever in low volume high density formats whilst providing high quality data. Within this world of rapid change, Pfizer has applied cutting edge technology to HTS by introducing screening in 1 microl formats utilising single molecule detection technology. Instead of resource intensive in-house development, Pfizer entered into a collaboration with Evotec OAI / Evotec Technologies and introduced their Mark-II EVOscreen platform. In this article we will outline the benefits of the approach taken at Pfizer, Sandwich, and introduce the Mark-II EVOscreen platform, illustrating the potential but also possible pitfalls of HTS miniaturisation.
Johansson, Madeleine; Hjärthag, Fredrik; Helldin, Lars
2018-05-01
A decade has passed since the standardized remission criteria of schizophrenia spectrum disorders-the Andreasen Criteria-were defined. Over 2000 studies have been published, but only a few describe symptomatic remission over time. In this prospective study we followed patients for 3 and 5years, respectively. The aim was to investigate how different symptoms affect the occurrence of remission and how the remission cut-off level affects remission sustainability. The participants were patients diagnosed with schizophrenia spectrum disorders (DSM-IV). First, the importance of each core symptom for remission was examined using the Positive and Negative Syndrome Scale (n=274). Second, we investigated which items affect patients to either go in and out of remission or never achieve remission (n=154). Third, we investigated how the sustainability of remission is affected by a cut-off set to 2 (minimal) and 3 (mild) points, respectively (n=154). All core symptoms affected the occurence of remission, to a higher or lesser extent. Delusions and Hallucinatory behavior contributed the strongest to fluctuation between remission and non-remission, while the contribution of Mannerism and posturing was very marginal. Negative symptoms were enhanced when remission was never achieved. Moreover, the study found that remission duration was significantly longer for the cut-off score 2 rather than 3. The study shows that, over time, remission criteria discriminate between being stable, unstable, or never in remission. Patients with only a minimal occurrence of symptom intensity exhibit a significantly longer remission duration compared to patients with mild symptom intensity, indicating that the treatment goal should be minimal symptom intensity. Copyright © 2017 Elsevier B.V. All rights reserved.
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.
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.
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.
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.
Interannual variability in the number of Northern Hemisphere Cut-off low systems.
NASA Astrophysics Data System (ADS)
Nieto, R.; Gimeno, L.; de La Torre, L.; Tesouro, M.; Añel, J. A.; Ribera, P.
2003-04-01
Cut-off low-pressure systems-COLS- are usually closed circulations at middle and upper troposphere developed from a deep trough in the westerlies. The importance of their study is due to both the convective severe events that can occur if they are over warm ocean and because they are important mechanisms of Stratosphere-troposphere exchange- STE-. However few is known about their interannual variability, due to the limited duration of the study (five years) of previous global climatologies. In this study we identify COLs systems in the Northern Hemisphere for a 41-year period (1958 to 1998) using an approach based in imposing the three main physical characteristics of the conceptual model of COL (a. closed circulation and minimum of geopotential, minimum of equivalent thickness, and two baroclinic zones, one in front of the low and the other behind the low). Data from NCAR-NCEP reanalysis were used. The aim of the study is to detect trends and to identify associations both with blocking events and major modes of climate variability. Results show that 1) in the Asian sector both less intense and more intense COLs had a significant positive trend whereas in the Pacific and the Atlantic sectors only less intense COLs had a significant positive trend, 2) Most of COLs were associated with blocking events, 3) During positive ENSO phases the number of less intense COLs in the Pacific were lower than during negative ENSO phases and 4) During positive Northern Annular Mode (NAM) phases the number of less intense COLs in the Atlantic were higher than during negative NAM phases.
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.
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%.
Defoliation effects on pasture photosynthesis and respiration
USDA-ARS?s Scientific Manuscript database
Ecosystem C gain or loss from managed grasslands can depend on the type and intensity of management practices that are employed. However, limited information is available at the field scale on how the type of defoliation, specifically grazing vs. cutting, affects gross primary productivity (GPP) an...
Brain damage treated with non proven intensive training 2003-2011: a Norwegian cost analysis.
Norum, Jan; Ramsvik, Arnborg; Tjeldnes, Knut
2012-10-10
There has been an increased request for intensive training and rehabilitation of patients with brain damage in Norway. These programs are demanding with regard to personnel, travelling, time and economic resources. We aimed to indicate cost and gain to make these programs cost-effective. A retrospective study included all patients referred to the Northern Norway Regional Health Authority (NNRHA) trust during the nine years period 2003-2011. All referrals to the NNRHA trust for the economic coverage of foreign based rehabilitation or habilitation programs (The Advanced Bio-Mechanical Rehabilitation (ABR), Institutes of Achievement of Human Potential program (IAHP) (Doman Method), Family Hope Center (FHC) program and the Kozijavkin Method) were included. 17 patients were detected and 15 fulfilled the inclusion criteria for funding. Median age was 8 years (1-31 years). Cost from the specialist health care point of view was calculated. A cut-off limit of €57,000/quality adjusted life year (QALY) and a 4% discount rate was employed. The undiscounted cost per patient enrolled was calculated €133,210 (discounted €121,348). To make these therapies cost effective, a total of at least 2.13 QALYs (2.34 undiscounted QALYs) must be gained per patient enrolled. Such a gain could not be indicated and we doubt it is achievable. Non-proven intensive training programs for patients with brain damage are costly. As long as their effect has not been documented, health care services should not spend resources on these programs outside clinical trials.
Extracting spatial information from networks with low-order eigenvectors
NASA Astrophysics Data System (ADS)
Cucuringu, Mihai; Blondel, Vincent D.; Van Dooren, Paul
2013-03-01
We consider the problem of inferring meaningful spatial information in networks from incomplete information on the connection intensity between the nodes of the network. We consider two spatially distributed networks: a population migration flow network within the US, and a network of mobile phone calls between cities in Belgium. For both networks we use the eigenvectors of the Laplacian matrix constructed from the link intensities to obtain informative visualizations and capture natural geographical subdivisions. We observe that some low-order eigenvectors localize very well and seem to reveal small geographically cohesive regions that match remarkably well with political and administrative boundaries. We discuss possible explanations for this observation by describing diffusion maps and localized eigenfunctions. In addition, we discuss a possible connection with the weighted graph cut problem, and provide numerical evidence supporting the idea that lower-order eigenvectors point out local cuts in the network. However, we do not provide a formal and rigorous justification for our observations.
Modelling and simulation of effect of ultrasonic vibrations on machining of Ti6Al4V.
Patil, Sandip; Joshi, Shashikant; Tewari, Asim; Joshi, Suhas S
2014-02-01
The titanium alloys cause high machining heat generation and consequent rapid wear of cutting tool edges during machining. The ultrasonic assisted turning (UAT) has been found to be very effective in machining of various materials; especially in the machining of "difficult-to-cut" material like Ti6Al4V. The present work is a comprehensive study involving 2D FE transient simulation of UAT in DEFORM framework and their experimental characterization. The simulation shows that UAT reduces the stress level on cutting tool during machining as compared to that of in continuous turning (CT) barring the penetration stage, wherein both tools are subjected to identical stress levels. There is a 40-45% reduction in cutting forces and about 48% reduction in cutting temperature in UAT over that of in CT. However, the reduction magnitude reduces with an increase in the cutting speed. The experimental analysis of UAT process shows that the surface roughness in UAT is lower than in CT, and the UATed surfaces have matte finish as against the glossy finish on the CTed surfaces. Microstructural observations of the chips and machined surfaces in both processes reveal that the intensity of thermal softening and shear band formation is reduced in UAT over that of in CT. Copyright © 2013 Elsevier B.V. All rights reserved.
[Cuff pressure control at the intersinve care unit: influence of nursing professionals' training].
Velasco Sanz, T R; Ronda Delgado de la Fuente, M; Sánchez de la Ventana, A B; Reyes Merino Martínez, M
2015-01-01
To analyze proper control of endotracheal cuff pressure in an intensive care unit. The specific objective is to verify whether training of nursing professionals improves monitoring endotracheal cuff pressure. the study type is descriptive, observational and retrospective. All patients were admitted to the Critical Unit II of the Clínico San Carlos Hospital between May 2010-November 2011, requiring either a tracheal tube or tracheal cannula. Studied variables were: number of in range measures, number of intubated patients, or with tracheal cannula and register. Four cuts were made on all admitted patients admitted during the study period in order to measure endotracheal cuff pressure. Two cuts were performed before the professional nurses training and the other two cuts after a specific training with respect to endotracheal cuff pressure and Zero pneumonia. There were 74 measurements. The first cut obtained 40.74% of measures in range. In the second cut 61.90% of measures were identified in range. In the third cut, it was found that 85.7% of measures were in range and in the fourth court, it was noted the 89.47% of measures were in range. Monitoring of the endotracheal cuff pressure was inadequate before specific training of professionals. Nursing professionals training facilitates the correct measurement of the endotracheal cuff pressure, which improves patient safety. Copyright © 2013 Elsevier España, S.L.U. y SEEIUC. All rights reserved.
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.
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
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.
Bautista, Ami C; Zhou, Lei; Jawa, Vibha
2013-10-01
Immunogenicity support during nonclinical biotherapeutic development can be resource intensive if supported by conventional methodologies. A universal indirect species-specific immunoassay can eliminate the need for biotherapeutic-specific anti-drug antibody immunoassays without compromising quality. By implementing the R's of sustainability (reduce, reuse, rethink), conservation of resources and greener laboratory practices were achieved in this study. Statistical analysis across four biotherapeutics supported identification of consistent product performance standards (cut points, sensitivity and reference limits) and a streamlined universal anti-drug antibody immunoassay method implementation strategy. We propose an efficient, fit-for-purpose, scientifically and statistically supported nonclinical immunogenicity assessment strategy. Utilization of a universal method and streamlined validation, while retaining comparability to conventional immunoassays and meeting the industry recommended standards, provides environmental credits in the scientific laboratory. Collectively, individual reductions in critical material consumption, energy usage, waste and non-environment friendly consumables, such as plastic and paper, support a greener laboratory environment.
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.
Balion, Cynthia; Grey, Vijaylaxmi; Ismaila, Afisi; Blatz, Susan; Seidlitz, Wendy
2006-11-03
Point of care (POC) glucose meters are routinely used as a screening tool for hypoglycemia in a neonatal setting. Glucose meters however, lack the same accuracy as laboratory instruments for glucose measurement. In this study we investigated potential reasons for this inaccuracy and established a cut off value for confirmatory testing. In this prospective study, all patients in the neonatal intensive care unit who had a plasma glucose test ordered were eligible to participate. Demographic information, sample collection information (nine variables) and a recent hematocrit value were recorded for each sample. Glucose measurements were taken at the bedside on the glucose meter (RN PCx) as well as in the laboratory on both the glucose meter (LAB PCx) and the laboratory analyzer (PG). Data were analyzed by simple and mixed-effects regression analysis and by analysis of a receiver operator characteristics (ROC) curve. There were 475 samples analyzed from 132 patients. RN PCx values were higher than PG values (mean = 4.9%), while LAB PCx results were lower (mean = -5.2%) than PG values. Only 31% of the difference between RN PCx--PG and 46% of the difference for LAB PCx--PG could be accounted for by the variables tested. The largest proportion of variance between PCx and PG measurements was explained by hematocrit (about 30%) with a greater effect seen at glucose concentrations < or =4.0 mmol/L (< or =72 mg/dL)(48% and 40% for RN PCx and LAB PCx, respectively). The ROC analysis showed that for detection of all cases of hypoglycemia (PG < 2.6 mmol/L)(PG < 47 mg/dL) the PCx screening cut off value would need to be set at 3.8 mmol/L (68 mg/dL) requiring 20% of all samples to have confirmatory analysis by the laboratory method. The large difference between glucose results obtained by PCx glucose meter compared to the laboratory analyzer can be explained in part by hematocrit and low glucose concentration. These results emphasize that the glucose meter is useful only as a screening device for neonatal hypoglycemia and that a screening cut off value must be established.
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...
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.
Liu, Qi; Cai, Hui-Ying; Jin, Guang-Ze
2013-10-01
To accurately quantify forest carbon density and net primary productivity (NPP) is of great significance in estimating the role of forest ecosystems in global carbon cycle. By using the forest inventory and allometry approaches, this paper measured the carbon density and NPP of the virgin broadleaved-Korean pine (Pinus koraiensis) forest and of the broadleaved-Korean pine forest after 34 years selective-cutting (the cutting intensity was 30%, and the cutting trees were in large diameter class). The total carbon density of the virgin and selective-cutting broadleaved-Korean pine forests was (397.95 +/- 93.82) and (355.61 +/- 59.37) t C x hm(-2), respectively. In the virgin forest, the carbon density of the vegetation, debris, and soil accounted for 31.0%, 3.1%, and 65.9% of the total carbon pool, respectively; in the selective-cutting forest, the corresponding values were 31.7%, 2.9%, and 65.4%, respectively. No significant differences were observed in the total carbon density and the carbon density of each component between the two forests. The total NPP of the virgin and selective-cutting forests was (36.27 +/- 0.36) and (6.35 +/- 0.70) t C x hm(-2) x a(-1), among which, the NPP of overstory, understory, and fine roots in virgin forest and selective-cutting forest accounted for 60.3%, 2.0%, and 37.7%, and 66.1%, 2.0%, and 31.2%, respectively. No significant differences were observed in the total NPP and the contribution rate of each component between the two forests. However, the ratios of the needle and broadleaf NPPs of the virgin and selective-cutting forests were 47.24:52.76 and 20.48:79.52, respectively, with a significant difference. The results indicated that the carbon density and NPP of the broadleaved-Korean pine forest after 34 years selective-cutting recovered to the levels of the virgin broadleaved-Korean pine forest.
Rotary ultrasonic machining of CFRP: A comparison with grinding.
Ning, F D; Cong, W L; Pei, Z J; Treadwell, C
2016-03-01
Carbon fiber reinforced plastic (CFRP) composites have been intensively used in various industries due to their superior properties. In aircraft and aerospace industry, a large number of holes are required to be drilled into CFRP components at final stage for aircraft assembling. There are two major types of methods for hole making of CFRP composites in industry, twist drilling and its derived multi-points machining methods, and grinding and its related methods. The first type of methods are commonly used in hole making of CFRP composites. However, in recent years, rotary ultrasonic machining (RUM), a hybrid machining process combining ultrasonic machining and grinding, has also been successfully used in drilling of CFRP composites. It has been shown that RUM is superior to twist drilling in many aspects. However, there are no reported investigations on comparisons between RUM and grinding in drilling of CFRP. In this paper, these two drilling methods are compared in five aspects, including cutting force, torque, surface roughness, hole diameter, and material removal rate. Copyright © 2015 Elsevier B.V. All rights reserved.
[Parallel virtual reality visualization of extreme large medical datasets].
Tang, Min
2010-04-01
On the basis of a brief description of grid computing, the essence and critical techniques of parallel visualization of extreme large medical datasets are discussed in connection with Intranet and common-configuration computers of hospitals. In this paper are introduced several kernel techniques, including the hardware structure, software framework, load balance and virtual reality visualization. The Maximum Intensity Projection algorithm is realized in parallel using common PC cluster. In virtual reality world, three-dimensional models can be rotated, zoomed, translated and cut interactively and conveniently through the control panel built on virtual reality modeling language (VRML). Experimental results demonstrate that this method provides promising and real-time results for playing the role in of a good assistant in making clinical diagnosis.
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.
Cutting Crime: Drug Courts in Action.
ERIC Educational Resources Information Center
Drug Strategies, Washington, DC.
Drug courts depart from traditional criminal justice practice by directing nonviolent drug abusing offenders to intensive court-supervised drug treatment instead of to prison. An examination of drug courts is offered in this booklet. The text is based on extensive interviews with judges, prosecutors, public defenders, court administrators, police…
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...
Intense Pulsed Light (IPL) in Aesthetic Dermatology
NASA Astrophysics Data System (ADS)
Pytras, B.; Drozdowski, P.; Zub, K.
2011-08-01
Introduction. Newer and newer technologies have been widely developed in recent years due to increasing need for aesthetic medicine procedures. Less invasive methods of skin imperfection and time-related lesions removal, IPL (Intense Pulse Light) being one of them, are gaining more and more interest. The shorter the "downtime" for the patient is and the more efficient the procedure results, the more popular the method becomes. Materials and methods_Authors analyse the results of treatment of a 571 patients-group (501 women and 70 men) aged 5-72 years in the period: October 2006-August 2010. IPL™ Quantum (Lumenis Ltd.) device with 560 nm. cut-off filter was used. Results. The results were regarded as: very good, good or satisfying (%):Skin photoaging symptomes 37/40/23, Isolated facial dyschromia 30/55/25, Isolated facial erythema 62/34/4, Lower limbs teleangiectasia 12/36/52, Keratosis solaris on hands 100/-/-. Approximately half of the patients developed transitory erythema and 25%- transitory, mild, circumscribed oedema. Following undesirable effects were noted: skin thermal irritation (6,1% of the patients) and skin hypopigmentation (2% of the patients). Discussion. Results and post-treatment management proposed by authors are similar to those reported by other authors. Conclusions. Treatment results of the 571-patients group prove IPL to be a very efficient method of non-ablative skin rejuvenation. It turned out effective also in lower limbs teleangiectasia treatment. It presents low risk of transitory and mild side effects. Futhermore, with short or no downtime, it is well-tolerated by the patients.
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.
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.
Pratinidhi, Asha K.; Bagade, Abhijit C.; Kakade, Satish V.; Kale, Hemangi P.; Kshirsagar, Vinayak Y.; Babar, Rohini; Bagal, Shilpa
2017-01-01
Background & objectives: Foot length of the newborn has a good correlation with the birth weight and is recommended to be used as a proxy measure. There can be variations in the measurement of foot length. A study was, therefore, carried out to develop a foot length calliper for accurate foot length measurement and to find cut-off values for birth weight and gestational age groups to be used by primary healthcare workers. Methods: This study was undertaken on 645 apparently healthy newborn infants with known gestational age. Nude birth weight was taken within 24 h of birth on a standard electronic weighing machine. A foot length calliper was developed. Correlation between foot length and birth weight as well as gestational age was calculated. Correctness of cut-off values was tested using another set of 133 observations on the apparently healthy newborns. Action-oriented colour coding was done to make it easy for primary healthcare workers to use it. Results: There was a significant correlation of foot length with birth weight (r=0.75) and gestational age (r=0.63). Cut-off values for birth weight groups were 6.1, 6.8 and 7.3 cm and for gestational age of 6.1, 6.8 and 7.0 cm. Correctness of these cut-off values ranged between 77.1 and 95.7 per cent for birth weight and 60-93.3 per cent for gestational age. Considering 2.5 kg as cut-off between normal birth weight and low birth weight (LBW), cut-off values of 6.1, 6.8 and 7.3 were chosen. Action-oriented colour coding was done by superimposing the colours on the scale of the calliper, green indicating home care, yellow indicating supervised home care, orange indicating care at newborn care units at primary health centres and red indicating Neonatal Intensive Care Unit care for infants. Interpretation & conclusions: A simple device was developed so that the primary health care workers and trained Accredited Social Health Activist workers can identify the risk of LBW in the absence of accurate weighing facilities and decide on the type of care needed by the newborn and take action accordingly. PMID:28749397
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.
A novel approach of deposition for uniform diamond films on circular saw blades
NASA Astrophysics Data System (ADS)
Hongxiu, ZHOU; Boya, YUAN; Jilei, LYU; Nan, JIANG
2017-11-01
Uniform diamond films are highly desirable for cutting industries, due to their high performance and long lifetime used on cutting tools. Nevertheless, they are difficult to obtain on cutting tools with complicated shapes, greatly limiting the applications of diamond films. In this study, a novel approach of deposition for uniform diamond films is proposed, on circular saw blades made of cemented carbide using reflectors of brass sheets. Diamond films are deposited using hot filament chemical vapor deposition (HFCVD). A novel concave structure of brass sheets is designed and fabricated, improving the distribution of temperature field, and overcoming the disadvantages of the conventional HFCVD systems. This increases the energy efficiency of use without changing the structure and increasing the cost of HFCVD. The grains are refined and the intensities of diamond peaks are strengthened obviously, which is confirmed by scanning electron microscopy and Raman spectra respectively.
NASA Astrophysics Data System (ADS)
Jia, Fuqiang; Liu, Pei; Li, Kang; Chen, Hao; Cheng, Yongjie; Cai, Zhiping; Copner, Nigel
2017-07-01
In this paper, a comparative study of passively Q-switched c-cut Nd:YVO4 and Nd:YAG lasers using four different layers CVD graphene as saturable absorber are demonstrated experimentally for the first time. Moreover, it is successful to accurately control the frequency of repetition rates of the CVD graphern passively Q-switched lasers by pulsed pump. The impacts of laser materials, layers of CVD graphene and cavity length on output parameters are investigated intensively as well, the result shows that the c-cut Nd:YVO4 is a promising laser media compared with Nd:YAG for passively Q-switched lasers based on CVD graphene, as it has better performances in pulse width, pulse energy and peak power. A useful and cost-effective way to generate stable pulsed lasers by CVD graphene or other novel saturable materials are demonstrated.
Reay, David S
2002-12-15
Debate over how, when, and even whether man-made greenhouse-gas emissions should be controlled has grown in intensity even faster than the levels of greenhouse gas in our atmosphere. Many argue that the costs involved in reducing emissions outweigh the potential economic damage of human-induced climate change. Here, existing cost-benefit analyses of greenhouse-gas reduction policies are examined, with a view to establishing whether any such global reductions are currently worthwhile. Potential for, and cost of, cutting our own individual greenhouse-gas emissions is then assessed. I find that many abatement strategies are able to deliver significant emission reductions at little or no net cost. Additionally, I find that there is huge potential for individuals to simultaneously cut their own greenhouse-gas emissions and save money. I conclude that cuts in global greenhouse-gas emissions, such as those of the Kyoto Protocol, cannot be justifiably dismissed as posing too large an economic burden.
Russell, Harold C.
1979-01-01
This disclosure describes a device for repeatably scribing a V-shaped scratch having sharply defined dimensions on the interior surface of a nuclear reactor fuel rod tube. A cutting tool having a V-shaped cutting tip is supported within the fuel rod tube so that the V-shaped cutting tip can be pivoted about an axis and scribe a scratch on the interior surface of the fuel rod tube. Lengthwise the scratch runs parallel to a line drawn through the axis of the fuel rod tube and is in the shape of an arc, and widthwise the scratch is V-shaped. This shape is used because the dimensions of the scratch can be plugged into appropriate formulas to calculate stress intensity of cracks in fuel rod tubes. Since the fuel rod tubes which are to be scribed may be radioactive, the scratching assembly is designed for use in a fixture which allows it to be operated in a cave by remote control handling devices.
Cutting Edge Research in Homeopathy: HRI's second international research conference in Rome.
Tournier, Alexander L; Roberts, E Rachel
2016-02-01
Rome, 3rd-5th June 2015, was the setting for the Homeopathy Research Institute's (HRI) second conference with the theme 'Cutting Edge Research in Homeopathy'. Attended by over 250 delegates from 39 countries, this event provided an intense two and a half day programme of presentations and a forum for the sharing of ideas and the creation of international scientific collaborations. With 35 oral presentations from leaders in the field, the scientific calibre of the programme was high and the content diverse. This report summarises the key themes underpinning the cutting edge data presented by the speakers, including six key-note presentations, covering advancements in both basic and clinical research. Given the clear commitment of the global homeopathic community to high quality research, the resounding success of both Barcelona 2013 and Rome 2015 HRI conferences, and the dedicated support of colleagues, the HRI moves confidently forward towards the next biennial conference. Copyright © 2015.
The Caenorhabditis elegans interneuron ALA is (also) a high-threshold mechanosensor
2013-01-01
Background To survive dynamic environments, it is essential for all animals to appropriately modulate their behavior in response to various stimulus intensities. For instance, the nematode Caenorhabditis elegans suppresses the rate of egg-laying in response to intense mechanical stimuli, in a manner dependent on the mechanosensory neurons FLP and PVD. We have found that the unilaterally placed single interneuron ALA acted as a high-threshold mechanosensor, and that it was required for this protective behavioral response. Results ALA was required for the inhibition of egg-laying in response to a strong (picking-like) mechanical stimulus, characteristic of routine handling of the animals. Moreover, ALA did not respond physiologically to less intense touch stimuli, but exhibited distinct physiological responses to anterior and posterior picking-like touch, suggesting that it could distinguish between spatially separated stimuli. These responses required neither neurotransmitter nor neuropeptide release from potential upstream neurons. In contrast, the long, bilaterally symmetric processes of ALA itself were required for producing its physiological responses; when they were severed, responses to stimuli administered between the cut and the cell body were unaffected, while responses to stimuli administered posterior to the cut were abolished. Conclusion C. elegans neurons are typically classified into three major groups: sensory neurons with specialized sensory dendrites, interneurons, and motoneurons with neuromuscular junctions. Our findings suggest that ALA can autonomously sense intense touch and is thus a dual-function neuron, i.e., an interneuron as well as a novel high-threshold mechanosensor. PMID:24341457
The Caenorhabditis elegans interneuron ALA is (also) a high-threshold mechanosensor.
Sanders, Jarred; Nagy, Stanislav; Fetterman, Graham; Wright, Charles; Treinin, Millet; Biron, David
2013-12-17
To survive dynamic environments, it is essential for all animals to appropriately modulate their behavior in response to various stimulus intensities. For instance, the nematode Caenorhabditis elegans suppresses the rate of egg-laying in response to intense mechanical stimuli, in a manner dependent on the mechanosensory neurons FLP and PVD. We have found that the unilaterally placed single interneuron ALA acted as a high-threshold mechanosensor, and that it was required for this protective behavioral response. ALA was required for the inhibition of egg-laying in response to a strong (picking-like) mechanical stimulus, characteristic of routine handling of the animals. Moreover, ALA did not respond physiologically to less intense touch stimuli, but exhibited distinct physiological responses to anterior and posterior picking-like touch, suggesting that it could distinguish between spatially separated stimuli. These responses required neither neurotransmitter nor neuropeptide release from potential upstream neurons. In contrast, the long, bilaterally symmetric processes of ALA itself were required for producing its physiological responses; when they were severed, responses to stimuli administered between the cut and the cell body were unaffected, while responses to stimuli administered posterior to the cut were abolished. C. elegans neurons are typically classified into three major groups: sensory neurons with specialized sensory dendrites, interneurons, and motoneurons with neuromuscular junctions. Our findings suggest that ALA can autonomously sense intense touch and is thus a dual-function neuron, i.e., an interneuron as well as a novel high-threshold mechanosensor.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Naunyka, V. N.; Shepelevich, V. V., E-mail: vasshep@inbox.ru
2011-05-15
The mutual transformation of light waves in the case of their simultaneous diffraction from a bulk reflection phase hologram, which was formed in a cubic photorefractive crystal of the 4-bar 3m symmetry class, has been studied. The indicator surfaces of the polarization-optimized values of the relative intensity of the object wave, which make it possible to determine the amplification of this wave for any crystal cut, are constructed. The linear polarization azimuths at which the energy exchange between the light waves reaches a maximum are found numerically for crystals of different cuts.
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.
Lightweight protective clothing for the safe handling of high-intensity pressurized lamps
NASA Technical Reports Server (NTRS)
Ewashinka, J. G.
1975-01-01
Five commercially available clothing materials, selected for their high cutting resistance, high strength, light weight and pliability, were tested by exposing them to exploding lamps located less than 60 cm (2 ft) away. Face shield material tested initially was commercial high-strength polycarbonate plastic.
Moving Past "Hello World": Learning to Mod in an Online Affinity Space
ERIC Educational Resources Information Center
Subramanian, Shree Durga
2012-01-01
Game modding has increasingly become a mainstream and "cutting edge" medium to foster a broad range of critical software design and programming practices to learners coming from wide-ranging educational and professional backgrounds. Participatory practices, like game modding, are highly interest-driven and entail intense engagement with…
W.H. McNab
1991-01-01
Soil moisture content was intensively sampled in three, 1-acre blocks containing an opening and surrounding mature upland hardwoods. Openings covering 0.19-0.26 ac were created by group-selection cutting, and they were occupied by 1-year-old trees and shrubs.
Deriving a GPS Monitoring Time Recommendation for Physical Activity Studies of Adults.
Holliday, Katelyn M; Howard, Annie Green; Emch, Michael; Rodríguez, Daniel A; Rosamond, Wayne D; Evenson, Kelly R
2017-05-01
Determining locations of physical activity (PA) is important for surveillance and intervention development, yet recommendations for using location recording tools like global positioning system (GPS) units are lacking. Specifically, no recommendation exists for the number of days study participants should wear a GPS to reliably estimate PA time spent in locations. This study used data from participants (N = 224, age = 18-85 yr) in five states who concurrently wore an ActiGraph GT1M accelerometer and a Qstarz BT-Q1000X GPS for three consecutive weeks to construct monitoring day recommendations through variance partitioning methods. PA bouts ≥10 min were constructed from accelerometer counts, and the location of GPS points was determined using a hand-coding protocol. Monitoring day recommendations varied by the type of location (e.g., participant homes vs parks) and the intensity of PA bouts considered (low and medium cut point moderate to vigorous PA [MVPA] bouts or high cut point vigorous PA [VPA] bouts). In general, minutes of all PA intensities spent in a given location could be measured with ≥80% reliability using 1-3 d of GPS monitoring for fitness facilities, schools, and footpaths. MVPA bout minutes in parks and roads required longer monitoring periods of 5-12 d. PA in homes and commercial areas required >19 d of monitoring. Twelve days of monitoring was found to reliably estimate minutes in both low and medium threshold MVPA as well as VPA bouts for many important built environment locations that can be targeted to increase PA at the population level. Minutes of PA in the home environment and commercial locations may be best assessed through other means given the lengthy estimated monitoring time required.
NASA Astrophysics Data System (ADS)
Alvarenga de Moura Meneses, Anderson; Giusti, Alessandro; de Almeida, André Pereira; Parreira Nogueira, Liebert; Braz, Delson; Cely Barroso, Regina; deAlmeida, Carlos Eduardo
2011-12-01
Synchrotron Radiation (SR) X-ray micro-Computed Tomography (μCT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-μCT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-μCT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-μCT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.
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
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).…
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…
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...
Meng, Qier; Kitasaka, Takayuki; Nimura, Yukitaka; Oda, Masahiro; Ueno, Junji; Mori, Kensaku
2017-02-01
Airway segmentation plays an important role in analyzing chest computed tomography (CT) volumes for computerized lung cancer detection, emphysema diagnosis and pre- and intra-operative bronchoscope navigation. However, obtaining a complete 3D airway tree structure from a CT volume is quite a challenging task. Several researchers have proposed automated airway segmentation algorithms basically based on region growing and machine learning techniques. However, these methods fail to detect the peripheral bronchial branches, which results in a large amount of leakage. This paper presents a novel approach for more accurate extraction of the complex airway tree. This proposed segmentation method is composed of three steps. First, Hessian analysis is utilized to enhance the tube-like structure in CT volumes; then, an adaptive multiscale cavity enhancement filter is employed to detect the cavity-like structure with different radii. In the second step, support vector machine learning will be utilized to remove the false positive (FP) regions from the result obtained in the previous step. Finally, the graph-cut algorithm is used to refine the candidate voxels to form an integrated airway tree. A test dataset including 50 standard-dose chest CT volumes was used for evaluating our proposed method. The average extraction rate was about 79.1 % with the significantly decreased FP rate. A new method of airway segmentation based on local intensity structure and machine learning technique was developed. The method was shown to be feasible for airway segmentation in a computer-aided diagnosis system for a lung and bronchoscope guidance system.
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.
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.
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.
Osewski, Pawel; Belardini, Alessandro; Petronijevic, Emilija; Centini, Marco; Leahu, Grigore; Diduszko, Ryszard; Pawlak, Dorota A.; Sibilia, Concita
2017-01-01
Second-order nonlinear optical materials are used to generate new frequencies by exploiting second-harmonic generation (SHG), a phenomenon where a nonlinear material generates light at double the optical frequency of the input beam. Maximum SHG is achieved when the pump and the generated waves are in phase, for example through birefringence in uniaxial crystals. However, applying these materials usually requires a complicated cutting procedure to yield a crystal with a particular orientation. Here we demonstrate the first example of phase matching under the normal incidence of SHG in a biaxial monoclinic single crystal of zinc tungstate. The crystal was grown by the micro-pulling-down method with the (102) plane perpendicular to the growth direction. Additionally, at the same time white light was generated as a result of stimulated Raman scattering and multiphoton luminescence induced by higher-order effects such as three-photon luminescence enhanced by cascaded third-harmonic generation. The annealed crystal offers SHG intensities approximately four times larger than the as grown one; optimized growth and annealing conditions may lead to much higher SHG intensities. PMID:28338074
NASA Astrophysics Data System (ADS)
Osewski, Pawel; Belardini, Alessandro; Petronijevic, Emilija; Centini, Marco; Leahu, Grigore; Diduszko, Ryszard; Pawlak, Dorota A.; Sibilia, Concita
2017-03-01
Second-order nonlinear optical materials are used to generate new frequencies by exploiting second-harmonic generation (SHG), a phenomenon where a nonlinear material generates light at double the optical frequency of the input beam. Maximum SHG is achieved when the pump and the generated waves are in phase, for example through birefringence in uniaxial crystals. However, applying these materials usually requires a complicated cutting procedure to yield a crystal with a particular orientation. Here we demonstrate the first example of phase matching under the normal incidence of SHG in a biaxial monoclinic single crystal of zinc tungstate. The crystal was grown by the micro-pulling-down method with the (102) plane perpendicular to the growth direction. Additionally, at the same time white light was generated as a result of stimulated Raman scattering and multiphoton luminescence induced by higher-order effects such as three-photon luminescence enhanced by cascaded third-harmonic generation. The annealed crystal offers SHG intensities approximately four times larger than the as grown one; optimized growth and annealing conditions may lead to much higher SHG intensities.
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.
Comparison of different focusing fiber tips for improved oral diode laser surgery.
Stock, Karl; Stegmayer, Thomas; Graser, Rainer; Förster, Wolfram; Hibst, Raimund
2012-12-01
State of the art for use of the fiber guided diode laser in dental therapy is the application of bare fibers. A novel concept with delivery fiber and exchangeable fiber tips enables the use of tips with special and optimized geometries for various applications. The aim of this study is the comparison of different focusing fiber tips for enhanced cutting efficacy in oral surgery. For this purpose various designs of tip geometry were investigated and optimized by ray tracing simulations. Two applicators, one with a sphere, and another one with a taper, were realized and tested on porcine gingiva (diode laser, 940 nm, 5 W/cw; 7 W/modulated). The cutting depth and quality were determined by light microscope. Histological sections of the cuts were prepared by a cryo-microtome and microscopically analyzed to determine the cut depths and thermal damage zones. The simulations show that, using a sphere as fiber tip, an intensity increase of up to a factor of 16.2 in air, and 13.2 in water compared to a bare 200 µm fiber can be achieved. Although offering high focusing factor in water, the cutting quality of the sphere was rather poor. This is probably caused by a derogation of the focusing quality due to contamination during cutting and light scattering. Much better results were achieved with conically shaped fiber tips. Compared to bare fibers they exhibit improved handling properties with no hooking, more regular and deeper cuts (5 W/cw: 2,393 ± 468 µm, compared to the cleaved bare fiber 5 W/cw: 711 ± 268 µm). The thermal damage zones of the cuts are comparable for the various tips and fibers. In conclusion the results of our study show that cutting quality and efficiency of diode laser on soft tissue can be significantly improved using conically shaped fiber tips. Copyright © 2012 Wiley Periodicals, Inc.
Vissers, Kris C. P.; van der Sande, Rob; Bronkhorst, Ewald; Lerou, Jos G. C.; Steegers, Monique A. H.
2017-01-01
Background Clinical experience teaches us that patients are willing to accept postoperative pain, despite high pain intensity scores. Nevertheless, relationships between pain scores and other methods of pain assessment, e.g. acceptability of pain or its interference with physical functioning, are not fully established. Our aims were to examine these relationships. Methods A cross-sectional study was conducted on patients who underwent major surgery between January 2008 and August 2013. Using logistic regression, we quantified the relationships between movement-evoked pain scores on the numerical rating scale (NRS-MEP) and three dichotomous dependent variables: patient’s opinion on acceptability of pain (PO: acceptable or unacceptable pain); nurses’ observation of patient’s performance of necessary activities to expedite recovery (NO: good or bad performance); a compound measure judging the presence of the clinically desirable situation of acceptable pain associated with good patients’ performance (PONO: present or not). Using Receiver Operating Characteristics (ROC) analysis, NRS cut-off points were determined such that they best discriminate between patients having one versus the other outcome for PO, NO and PONO. Results 15,394 assessments were obtained in 9,082 patients in the first three postoperative days. Nine percent of the patients had unacceptable pain while having an NRS-MEP of 0–4. An estimated 47% (95%CI = 45%-49%) of patients with an NRS-MEP of 7 described their pain as acceptable on day one. Moreover, 33% (31%-35%) performed all required physical activities, and 22% (21%-24%) combined acceptable pain with appropriate movement. NRS cut-off points for PO, NO and PONO were five, four and four, respectively, but had insufficient discriminatory power. Conclusions Our results suggest pain management should be guided by the many dimensions of the patient’s pain experience, not solely by NRS cut-off points. Future research should evaluate the impact of such multidimensional pain assessment on patients’ functional outcome. PMID:28489926
High-Intensity Focused Ultrasound Therapy: an Overview for Radiologists
Kim, Young-sun; Choi, Min Joo; Lim, Hyo Keun; Choi, Dongil
2008-01-01
High-intensity focused ultrasound therapy is a novel, emerging, therapeutic modality that uses ultrasound waves, propagated through tissue media, as carriers of energy. This completely non-invasive technology has great potential for tumor ablation as well as hemostasis, thrombolysis and targeted drug/gene delivery. However, the application of this technology still has many drawbacks. It is expected that current obstacles to implementation will be resolved in the near future. In this review, we provide an overview of high-intensity focused ultrasound therapy from the basic physics to recent clinical studies with an interventional radiologist's perspective for the purpose of improving the general understanding of this cutting-edge technology as well as speculating on future developments. PMID:18682666
2012-01-01
Background Because of the large volume of data and the intrinsic variation of data intensity observed in microarray experiments, different statistical methods have been used to systematically extract biological information and to quantify the associated uncertainty. The simplest method to identify differentially expressed genes is to evaluate the ratio of average intensities in two different conditions and consider all genes that differ by more than an arbitrary cut-off value to be differentially expressed. This filtering approach is not a statistical test and there is no associated value that can indicate the level of confidence in the designation of genes as differentially expressed or not differentially expressed. At the same time the fold change by itself provide valuable information and it is important to find unambiguous ways of using this information in expression data treatment. Results A new method of finding differentially expressed genes, called distributional fold change (DFC) test is introduced. The method is based on an analysis of the intensity distribution of all microarray probe sets mapped to a three dimensional feature space composed of average expression level, average difference of gene expression and total variance. The proposed method allows one to rank each feature based on the signal-to-noise ratio and to ascertain for each feature the confidence level and power for being differentially expressed. The performance of the new method was evaluated using the total and partial area under receiver operating curves and tested on 11 data sets from Gene Omnibus Database with independently verified differentially expressed genes and compared with the t-test and shrinkage t-test. Overall the DFC test performed the best – on average it had higher sensitivity and partial AUC and its elevation was most prominent in the low range of differentially expressed features, typical for formalin-fixed paraffin-embedded sample sets. Conclusions The distributional fold change test is an effective method for finding and ranking differentially expressed probesets on microarrays. The application of this test is advantageous to data sets using formalin-fixed paraffin-embedded samples or other systems where degradation effects diminish the applicability of correlation adjusted methods to the whole feature set. PMID:23122055
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.
Manipulation of the micro and macro-structure of beams extracted from cyclotrons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laxdal, R.E.
1995-09-01
It is standard practice in cyclotrons to alter the extracted micro-pulse width by using center-region slits and/or by chopping the beam before injection. The macro-structure can also be varied by means of pulsed or sinusoidal deflection devices before injection and/or after extraction. All above methods, however, involve cutting away the unwanted beam, thus reducing the time-averaged intensity. This paper will focus on some methods used to alter the time structure of extracted beams without significant beam loss. For example radial gradients in the accelerating fields from rf cavities can be utilized to compress, expand or even split longitudinally the circulatingmore » particle bunches. The macro-structure of the extracted beam can be altered by employing resonant extraction methods and replacing the static magnetic bump with either a pulsed or a sinusoidal transverse perturbation. The methods are most suitable for H cyclotrons but may also be considered in a limited scope for cyclotrons using direct extraction. Results of computer simulations and beam tests on the TRIUMF 500 MeV H{sup {minus}} cyclotron will be presented.« less
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
2013-01-01
Background Treatment duration varies with the type of therapy and a patient’s recovery speed. Including such a variation in randomized controlled trials (RCTs) enables comparison of the actual therapeutic potential of different therapies in clinical care. An index, Treatment Duration Control (TDC) of outcome scores was developed to help decide when to end treatment and also to determine treatment outcome by a blinded assessor. In contrast to traditional Routine Outcome Monitoring which considers raw score changes, TDC uses relative change. Methods Our theory shows that if a patient with the largest baseline scores in a sample requires a relative decrease by treatment factor T to reach a zone of low score values (functional status), any patient with smaller baselines will attain functional status with T. Furthermore, the end score values are proportional to the baseline. These characteristics concur with findings from the literature that a patient’s assessment of ‘much improved’ following treatment (related to attaining functional status) is associated with a particular relative decrease in pain intensity yielding a final pain intensity that is proportional to the baseline. Regarding the TDC-procedure: those patient’s scores that were related to pronounced signs and symptoms, were selected for adaptive testing (reference scores). A Contrast-value was determined for each reference score between its reference level and a subsequent level, and averaging all Contrast-values yielded TDC. A cut-off point related to factor T for attaining functional status, was the TDC-criterion to end a patient’s treatment as being successful. The use of TDC has been illustrated in RCT data from 118 chronic pain patients with myogenous Temporomandibular Disorders, and the TDC-criterion was validated. Results The TDC-criterion of successful/unsuccessful treatment approximated the cut-off separating two patient subgroups in a bimodal post-treatment distribution of TDC-values. Pain intensity decreased to residual levels and Health-Related Quality of Life (HRQoL) increased to normal levels, following successful treatment according to TDC. The post-treatment TDC-values were independent from the baseline values of pain intensity or HRQoL, and thus independent from the patient’s baseline severity of myogenous Temporomandibular Disorders. Conclusions TDC enables RCTs that have a variable therapy- and patient-specific duration. PMID:24112821
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.
Template-based automatic extraction of the joint space of foot bones from CT scan
NASA Astrophysics Data System (ADS)
Park, Eunbi; Kim, Taeho; Park, Jinah
2016-03-01
Clean bone segmentation is critical in studying the joint anatomy for measuring the spacing between the bones. However, separation of the coupled bones in CT images is sometimes difficult due to ambiguous gray values coming from the noise and the heterogeneity of bone materials as well as narrowing of the joint space. For fine reconstruction of the individual local boundaries, manual operation is a common practice where the segmentation remains to be a bottleneck. In this paper, we present an automatic method for extracting the joint space by applying graph cut on Markov random field model to the region of interest (ROI) which is identified by a template of 3D bone structures. The template includes encoded articular surface which identifies the tight region of the high-intensity bone boundaries together with the fuzzy joint area of interest. The localized shape information from the template model within the ROI effectively separates the bones nearby. By narrowing the ROI down to the region including two types of tissue, the object extraction problem was reduced to binary segmentation and solved via graph cut. Based on the shape of a joint space marked by the template, the hard constraint was set by the initial seeds which were automatically generated from thresholding and morphological operations. The performance and the robustness of the proposed method are evaluated on 12 volumes of ankle CT data, where each volume includes a set of 4 tarsal bones (calcaneus, talus, navicular and cuboid).
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.
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...
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.
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.
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.
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.
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
Computer-aided analysis of cutting processes for brittle materials
NASA Astrophysics Data System (ADS)
Ogorodnikov, A. I.; Tikhonov, I. N.
2017-12-01
This paper is focused on 3D computer simulation of cutting processes for brittle materials and silicon wafers. Computer-aided analysis of wafer scribing and dicing is carried out with the use of the ANSYS CAE (computer-aided engineering) software, and a parametric model of the processes is created by means of the internal ANSYS APDL programming language. Different types of tool tip geometry are analyzed to obtain internal stresses, such as a four-sided pyramid with an included angle of 120° and a tool inclination angle to the normal axis of 15°. The quality of the workpieces after cutting is studied by optical microscopy to verify the FE (finite-element) model. The disruption of the material structure during scribing occurs near the scratch and propagates into the wafer or over its surface at a short range. The deformation area along the scratch looks like a ragged band, but the stress width is rather low. The theory of cutting brittle semiconductor and optical materials is developed on the basis of the advanced theory of metal turning. The fall of stress intensity along the normal on the way from the tip point to the scribe line can be predicted using the developed theory and with the verified FE model. The crystal quality and dimensions of defects are determined by the mechanics of scratching, which depends on the shape of the diamond tip, the scratching direction, the velocity of the cutting tool and applied force loads. The disunity is a rate-sensitive process, and it depends on the cutting thickness. The application of numerical techniques, such as FE analysis, to cutting problems enhances understanding and promotes the further development of existing machining technologies.
Operationalization of Strategic Change in Continuing Education
ERIC Educational Resources Information Center
Wong, Evia O. W.
2005-01-01
Purpose: Hong Kong continuing education has encountered vigorous change in recent years. It is not limited to the mode of teaching and learning. Changing government policies, fund cutting to the higher education system and the entry of overseas university degrees increase the intensity of competition in the environment to an extraordinary extent.…
Wildlife-Habitat Relationships in California's Oak Woodlands: Where Do We Go From Here?
Michael L. Morrison; William M. Block; Jared Verner
1991-01-01
We discuss management goals and research directions for a comprehensive study of wildlife in California's oak woodlands. Oak woodlands are under intensive multiple use, including urbanization, recreation, grazing, fuel wood cutting, and hunting. Research in oak woodlands is thus complicated by these numerous, often competing, interests. Complicating understanding...
Fermilab | Science | Particle Accelerators | Advanced Superconducting Test
Accelerators for science and society Particle Physics 101 Science of matter, energy, space and time How Technology (FAST) Facility is America's only test bed for cutting-edge, record high-intensity particle beams in the United States as a particle beam research facility based on superconducting radio-frequency
29 CFR 1926.102 - Eye and face protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... protection Acetylene—Burning, Acetylene—Cutting, Acetylene—Welding Sparks, harmful rays, molten metal, flying...). Chipping Flying particles 1, 3, 4, 5, 6, 7A, 8A. Electric (arc) welding Sparks, intense rays, molten metal..., molten metal 7, 8, 9 (For severe exposure add 10). Grinding—Light Flying particles 1, 3, 4, 5, 6, 10...
29 CFR 1926.102 - Eye and face protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... protection Acetylene—Burning, Acetylene—Cutting, Acetylene—Welding Sparks, harmful rays, molten metal, flying...). Chipping Flying particles 1, 3, 4, 5, 6, 7A, 8A. Electric (arc) welding Sparks, intense rays, molten metal..., molten metal 7, 8, 9 (For severe exposure add 10). Grinding—Light Flying particles 1, 3, 4, 5, 6, 10...
29 CFR 1926.102 - Eye and face protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... protection Acetylene—Burning, Acetylene—Cutting, Acetylene—Welding Sparks, harmful rays, molten metal, flying...). Chipping Flying particles 1, 3, 4, 5, 6, 7A, 8A. Electric (arc) welding Sparks, intense rays, molten metal..., molten metal 7, 8, 9 (For severe exposure add 10). Grinding—Light Flying particles 1, 3, 4, 5, 6, 10...
A. Seki; D.L. Sirois; T. Kamen
1982-01-01
This xction explains the harvesting system selected. based upon topography, soil condition, and tree size. It is a highly mechmized, capital intensive system which includes tracked feller-bunchers to cut and bunch the trees. and trucked forwarders to transport the bunched trees to a whole tree chipper. The chips will be loaded into vans and transported to a designated...
Yield performance and bean quality traits of cacao propagated by somatic embryogenesis and grafting
USDA-ARS?s Scientific Manuscript database
Twelve cacao (Theobroma cacao) clones propagated by grafting and rooted cuttings of somatic embryo-derived plants were grown on an Ultisol soil at Corozal, Puerto Rico and evaluated for six years under intensive management. Year, variety, the year x variety and propagation treatment x variety intera...
Complex Systems, Interdisciplinary Collaboration, and Institutional Renewal
ERIC Educational Resources Information Center
Plank, Jeffrey; Feldon, David; Sherman, William; Elliot, Jennifer
2011-01-01
Research-intensive universities enjoy--or suffer--a paradoxical reputation: They are thought to be dedicated to both cutting-edge research and to the preservation of the canon. They are seen as broad and diverse communities of scholars with a vibrant collective intellectual life, yet also as silos of disciplinary entrenchment. Most significantly,…
Trends in streamflow and suspended sediment after logging, North Fork Caspar Creek
Jack Lewis; Elizabeth T. Keppeler
2007-01-01
Streamflow and suspended sediment were intensively monitored at fourteen gaging stations before and after logging a second-growth redwood (Sequoia sempervirens) forest. About 50 percent of the watershed was harvested, primarily by clear-cutting with skyline-cable systems. New road construction and tractor skidding were restricted to gently-sloping...
ERIC Educational Resources Information Center
Kashner, Zoe
2010-01-01
Corporate workers know what it means when cost-cutting consultants come to the office. Jobs will be eliminated. Employees who remain may have to do more work with less help. And new processes will reshape the organization, often from top to bottom. Although it can be an intensely disturbing event, bringing in consultants is not an exercise in…
Increasing participation in prevention research: strategies for youths, parents, and schools.
Hooven, Carole; Walsh, Elaine; Willgerodt, Mayumi; Salazar, Amy
2011-08-01
Subject participation is a critical concern for clinicians and researchers involved in prevention programs, especially for intensive interventions that require randomized assignment and lengthy youth and parent involvement. This article describes details of an integrated approach used to recruit and retain at-risk high school youths, their parents, and high schools to two different comprehensive, "indicated" prevention programs. Parent and youth recruitment and retention data for the two studies is provided in support of the approach described. A coordinated, multilevel approach, organized around cross-cutting issues, is described in detail as a response to the challenges of including vulnerable populations in intervention research. Methods are relevant to nurse clinicians who deliver prevention programs, and are important to clinical research that relies upon adequate participation in research programs. © 2011 Wiley Periodicals, Inc.
The Structure of Reclaiming Warehouse of Minerals at Open-Cut Mines with the Use Combined Transport
NASA Astrophysics Data System (ADS)
Ikonnikov, D. A.; Kovshov, S. V.
2017-07-01
In the article performed an analysis of ore reclaiming and overloading point characteristics at modern opencast mines. Ore reclaiming represents the most effective way of stability support of power-intensive and expensive technological dressing process, and, consequently, of maintenance of the optimal production and set-up parameters of extraction and quality of finished product. The paper proposed the construction of the warehouse describing the technology of its creation. Equipment used for the warehouse described in detail. All stages of development and operation was shown. Advantages and disadvantages of using mechanical shovel excavator and hydraulic excavator “backdigger” as a reloading and reclaiming equipment was compared. Ore reclaiming and overloading point construction at cyclical and continuous method of mining using a hydraulic excavator “backdigger” was proposed.
Effect sizes and cut-off points: a meta-analytical review of burnout in latin American countries.
García-Arroyo, Jose; Osca Segovia, Amparo
2018-05-02
Burnout is a highly prevalent globalized health issue that causes significant physical and psychological health problems. In Latin America research on this topic has increased in recent years, however there are no studies comparing results across countries, nor normative reference cut-offs. The present meta-analysis examines the intensity of burnout (emotional exhaustion, cynicism and personal accomplishment) in 58 adult nonclinical samples from 8 countries (Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Peru and Venezuela). We found low intensity of burnout but there are significant differences between countries in emotional exhaustion explained by occupation and language. Social and human service professionals (police officers, social workers, public administration staff) are more exhausted than health professionals (physicians, nurses) or teachers. The samples with Portuguese language score higher in emotional exhaustion than Spanish, supporting the theory of cultural relativism. Demographics (sex, age) and study variables (sample size, instrument), were not found significant to predict burnout. The effect size and confidence intervals found are proposed as a useful baseline for research and medical diagnosis of burnout in Latin American countries.
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.
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.
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.
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...
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.
Launay, David; Schmidt, Jean; Lepers, Sébastien; Mirault, Tristan; Lambert, Marc; Kyndt, Xavier; Reumaux, Dominique; Duhamel, Alain; Hachulla, Eric; Hatron, Pierre-Yves; Prin, Lionel; Dubucquoi, Sylvain
2010-07-04
Among anti-double-strand (ds)DNA antibody assays, Farr radioimmunoassay is decreasingly used because it requires radioactive material and is labor intensive. We evaluated the performance of Farr, three commercial enzyme immunoassays (EIAs) and the Crithidia luciliae immunofluorescence test (CLIFT) in systemic lupus erythematosus (SLE). Anti-dsDNA antibodies were determined in 99 SLE patients, 101 healthy subjects, and 53 patients with autoimmune rheumatic diseases. Farr performed better than the 3 EIAs and CLIFT for the diagnosis of SLE at the manufacturer's cut off and at the cut off set to achieve a specificity of 95%. To achieve a similar level of specificity, some EIAs had a decrease in sensitivity which was dramatic for some tests. Farr was also the best at distinguishing patients with quiescent to mildly active disease from patients with more active disease at the cut off value of 93 IU/ml. Using manufacturer's cut off did not allow distinguishing between patients with quiescent and active SLE. Farr was the best global test to assess the level of anti-dsDNA antibodies for both diagnosis and disease activity evaluation in SLE with adequately determined cut off values. Some EIA had low performances limiting their use in decision-making regarding diagnosis and/or treatment. Copyright 2010 Elsevier B.V. All rights reserved.
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.
Kim, Yoon-Hee; Jeong, Seul-Gi; Back, Kyeong-Hwan; Park, Ki-Hwan; Chung, Myung-Sub; Kang, Dong-Hyun
2013-09-16
The effect of various conditions on inactivation of foodborne pathogens and quality of fresh-cut lettuce during ultraviolet (254 nm, UVC) radiation was investigated. Lettuce was inoculated with a cocktail of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes and treated at different temperatures (4 and 25 °C), distances between sample and lamp (10 and 50 cm), type of exposure (illuminated from one or two sides), UV intensities (1.36 to 6.80 mW/cm²), and exposure times (0.5 to 10 min), sequentially. UV treatment at 25 °C for 1 min achieved 1.45-, 1.35-, and 2.12-log reductions in surface-inoculated E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively, whereas the reduction of these pathogens at 4 °C was 0.31, 0.57, and 1.16 log, respectively. UV radiation was most effective when distance from UV lamp to the sample was minimal (10 cm) and radiation area was maximal (two-sided exposure). All UV intensities significantly (P<0.05) reduced the three pathogens after 10 min exposure, but the effect of treatment was correlated with UV intensity and exposure time. Color values and texture parameters of lettuce subjected to UV treatment under the optimum conditions (25 °C, 10 cm between sample and lamp, two-sided exposure, 6.80 mW/cm²) were not significantly (P>0.05) different from those of nontreated samples up to 5 min exposure. However, these qualities significantly (P<0.05) changed at prolonged treatment time. These results suggest that UV radiation under optimized conditions could reduce foodborne pathogens without adversely affecting color quality properties of fresh-cut lettuce. © 2013 Elsevier B.V. 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...
19 CFR 134.43 - Methods of marking specific articles.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 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...
Many engineers and hydrologists use the curve number method to estimate runoff from ungaged watersheds; however, the method does not explicitly account for the influence of season or forest cutting on runoff. This study of observed rainfall and runoff for small, forested watershe...
A major benefit of trenchless rehabilitation technologies touted by many practitioners when comparing their products with traditional open cut construction methods is lower carbon dioxide (CO2) emissions. In an attempt to verify these claims, multiple tools have been d...
A major benefit of trenchless rehabilitation technologies touted by many practitioners when comparing their products with tradition open cut construction methods is lower carbon dioxide (CO2) emissions. In an attempt to verify these claims, multiple tools have been dev...
USDA-ARS?s Scientific Manuscript database
Multispectral imaging algorithms were developed using visible-near-infrared (VNIR) and near-infrared (NIR) hyperspectral imaging (HSI) techniques to detect worms on fresh-cut lettuce. The optimal wavebands that detect worm on fresh-cut lettuce for each type of HSI were investigated using the one-way...
Rooting common and cat greenbrier
Franz L. Pogge; John D. Gill; Bradford C. Bearce
1974-01-01
Because reliable methods for propagating greenbriers are needed for wildlife-habitat purposes, we tested stem and rhizome cuttings of common and cat greenbrier and tubers of the latter species. Common greenbrier is the better species for most wildlife habitat uses. It proved fairly easy to propagate from either stem or rhizome cuttings. Similar cuttings from cat...
Financial aspects of partial cutting practices in central Appalachian hardwoods
Gary W. Miller; Gary W. Miller
1993-01-01
Uneven-aged silvicultural practices can be used to regenerate and manage many eastern hardwood stands. Single-tree selection methods are feasible in stands where a desirable shade-tolerant commercial species can be regenerated following periodic harvests. A variety of partial cutting practices, including single-tree selection and diameter-limit cutting have been used...
Retail Meat Cutting I. Apprentice Meat Cutter Related Training. Revised.
ERIC Educational Resources Information Center
Johnson, Dale H., Ed.
Intended as a first-year curriculum for apprentice meat cutters, this text focuses on retail meat cutting. Topics covered in the 24 chapters are background and purpose of apprenticeship, job preparation, general layout of the meat department, operational procedures, beef structure and evaluation, retail cuts and cooking methods, beef forequarter:…
Ashbaugh, Fred N.; Murry, Kenneth R.
1988-12-27
A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.
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)
Farji-Brener, Alejandro G.; Lescano, María Natalia
2017-11-01
In arid environments, the high availability of sunlight due to the scarcity of trees suggests that plant competition take place mainly belowground for water and nutrients. However, the occurrence of soil disturbances that increase nutrient availability and thereby promote plant growth may enhance shoot competition between neighboring plants. We conducted a greenhouse experiment to evaluate the influence of the enriched soil patches generated by the leaf-cutting ant, Acromyrmex lobicornis, on the performance of the alien forb Carduus thoermeri (Asteraceae) under different intraspecific competition scenarios. Our results showed that substrate type and competition scenario affected mainly aboveground plant growth. As expected, plants growing without neighbors and in nutrient-rich ant refuse dumps showed more aboveground biomass than plants growing with neighbors and in nutrient-poor steppe soils. However, aboveground competition was more intense in nutrient-poor substrates: plants under shoot and full competition growing in the nutrient-rich ant refuse dumps showed higher biomass than those growing on steppe soils. Belowground biomass was similar among focal plants growing under different substrate type. Our results support the traditional view that increments in resource availability reduce competition intensity. Moreover, the fact that seedlings in this sunny habitat mainly compete aboveground illustrates how limiting factors may be scale-dependent and change in importance as plants grow.
Paper Test Cards for Presumptive Testing of Very Low Quality Antimalarial Medications
Weaver, Abigail A.; Lieberman, Marya
2015-01-01
Carrying out chemical analysis of antimalarials to detect low-quality medications before they reach a patient is a costly venture. Here, we show that a library of chemical color tests embedded on a paper card can presumptively identify formulations corresponding to very low quality antimalarial drugs. The presence or absence of chloroquine (CQ), doxycycline (DOX), quinine, sulfadoxine, pyrimethamine, and primaquine antimalarial medications, in addition to fillers used in low-quality pharmaceuticals, are indicated by patterns of colors that are generated on the test cards. Test card sensitivity for detection of these pure components ranges from 90% to 100% with no false positives in the absence of pharmaceutical. The color intensities from reactions characteristic of CQ or DOX allowed visual detection of formulations of these medications cut with 60% or 100% filler, although samples cut with 30% filler could not be reliably detected colorimetrically. However, the addition of unexpected fillers, even in 30% quantities, or substitute pharmaceuticals, could sometimes be detected by other color reactions on the test cards. Tests are simple and inexpensive enough to be carried out in clinics, pharmacies, and ports of entry and could provide a screening method to presumptively indicate very low quality medicines throughout the supply chain. PMID:25897064
NASA Astrophysics Data System (ADS)
Gómez-Urrea, H. A.; Escorcia-García, J.; Duque, C. A.; Mora-Ramos, M. E.
2017-11-01
The transmittance spectrum of a one-dimensional hybrid photonic crystal built from the suitable arrangement of periodic and quasiregular Rudin-Shapiro heterolayers that include superconducting slabs is investigated. The four-layer Rudin-Shapiro structure is designed with three lossless dielectric layers and a low-temperature superconductor one. The dielectric function of the superconducting layer is modeled by the two-fluid Gorter-Casimir theory, and the transmittance is calculated with the use of the transfer matrix method. The obtained results reveal the presence of a cut-off frequency fc - a forbidden frequency band for propagation - that can be manipulated by changing the width of the superconducting layer, the temperature and the order of the Rudin-Shapiro sequence. In addition, the spatial distribution of the electric field amplitude for the propagating TM modes is also discussed. It is found that the maximum of localized electric field relative intensity - which reaches a value of several tens - corresponds to the frequency values above to the cut-off frequency, at which, the effective dielectric function of the hybrid unit cell becomes zero. The proposed structure could be another possible system for optical device design for temperature-dependent optical devices such as stop-band filters, or as bolometers.
Numerical simulation of rock fragmentation during cutting by conical picks under confining pressure
NASA Astrophysics Data System (ADS)
Li, Xuefeng; Wang, Shibo; Ge, Shirong; Malekian, Reza; Li, Zhixiong
2017-12-01
In this article, the effect of confining pressure on rock fragmentation process during cutting was investigated by numerical simulation with a discrete element method (DEM). Four kinds of sandstones with different physical properties were simulated in the rock cutting models under different confining pressures. The rock fragmentation process, the cutting force, and the specific energy under different confining pressures were analyzed. With the increase in confining pressure and rock strength, the vertical propagation of cracks was restrained. Rock samples were compacted and strengthened by confining pressure resulting in the increase of the cutting force. The specific energy of rock cutting linearly increased with the increase of the confining pressure ratio.
Hypervelocity cutting machine and method
Powell, J.R.; Reich, M.
1996-11-12
A method and machine are provided for cutting a workpiece such as concrete. A gun barrel is provided for repetitively loading projectiles therein and is supplied with a pressurized propellant from a storage tank. A thermal storage tank is disposed between the propellant storage tank and the gun barrel for repetitively receiving and heating propellant charges which are released in the gun barrel for repetitively firing projectiles therefrom toward the workpiece. In a preferred embodiment, hypervelocity of the projectiles is obtained for cutting the concrete workpiece by fracturing thereof. 10 figs.
Method for laser welding ultra-thin metal foils
Pernicka, J.C.; Benson, D.K.; Tracy, C.E.
1996-03-26
A method for simultaneously cutting and welding ultra-thin foils having a thickness of less than 0.002 inches wherein two ultra-thin films are stacked and clamped together. A pulsed laser such as of the Neodymium: YAG type is provided and the beam of the laser is directed onto the stacked films to cut a channel through the films. The laser is moved relative to the stacked foils to cut the stacked foils at successive locations and to form a plurality of connected weld beads to form a continuous weld. 5 figs.
Method for laser welding ultra-thin metal foils
Pernicka, John C.; Benson, David K.; Tracy, C. Edwin
1996-01-01
A method for simultaneously cutting and welding ultra-thin foils having a thickness of less than 0.002 inches wherein two ultra-thin films are stacked and clamped together. A pulsed laser such as of the Neodymium: YAG type is provided and the beam of the laser is directed onto the stacked films to cut a channel through the films. The laser is moved relative to the stacked foils to cut the stacked foils at successive locations and to form a plurality of connected weld beads to form a continuous weld.
In-situ stabilization of radioactive zirconium swarf
Hess, Clay C.
1999-01-01
The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes.
Heuristic algorithms for solving of the tool routing problem for CNC cutting machines
NASA Astrophysics Data System (ADS)
Chentsov, P. A.; Petunin, A. A.; Sesekin, A. N.; Shipacheva, E. N.; Sholohov, A. E.
2015-11-01
The article is devoted to the problem of minimizing the path of the cutting tool to shape cutting machines began. This problem can be interpreted as a generalized traveling salesman problem. Earlier version of the dynamic programming method to solve this problem was developed. Unfortunately, this method allows to process an amount not exceeding thirty circuits. In this regard, the task of constructing quasi-optimal route becomes relevant. In this paper we propose options for quasi-optimal greedy algorithms. Comparison of the results of exact and approximate algorithms is given.
NASA Astrophysics Data System (ADS)
Octarina, Sisca; Radiana, Mutia; Bangun, Putra B. J.
2018-01-01
Two dimensional cutting stock problem (CSP) is a problem in determining the cutting pattern from a set of stock with standard length and width to fulfill the demand of items. Cutting patterns were determined in order to minimize the usage of stock. This research implemented pattern generation algorithm to formulate Gilmore and Gomory model of two dimensional CSP. The constraints of Gilmore and Gomory model was performed to assure the strips which cut in the first stage will be used in the second stage. Branch and Cut method was used to obtain the optimal solution. Based on the results, it found many patterns combination, if the optimal cutting patterns which correspond to the first stage were combined with the second stage.
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.
NASA Astrophysics Data System (ADS)
Jokiaho, T.; Laitinen, A.; Santa-aho, S.; Isakov, M.; Peura, P.; Saarinen, T.; Lehtovaara, A.; Vippola, M.
2017-12-01
Heavy steel plates are used in demanding applications that require both high strength and hardness. An important step in the production of such components is cutting the plates with a cost-effective thermal cutting method such as flame cutting. Flame cutting is performed with a controlled flame and oxygen jet, which burns the steel and forms a cutting edge. However, the thermal cutting of heavy steel plates causes several problems. A heat-affected zone (HAZ) is generated at the cut edge due to the steep temperature gradient. Consequently, volume changes, hardness variations, and microstructural changes occur in the HAZ. In addition, residual stresses are formed at the cut edge during the process. In the worst case, unsuitable flame cutting practices generate cracks at the cut edge. The flame cutting of thick steel plate was modeled using the commercial finite element software ABAQUS. The results of modeling were verified by X-ray diffraction-based residual stress measurements and microstructural analysis. The model provides several outcomes, such as obtaining more information related to the formation of residual stresses and the temperature history during the flame cutting process. In addition, an extensive series of flame cut samples was designed with the assistance of the model.
A review on ductile mode cutting of brittle materials
NASA Astrophysics Data System (ADS)
Antwi, Elijah Kwabena; Liu, Kui; Wang, Hao
2018-06-01
Brittle materials have been widely employed for industrial applications due to their excellent mechanical, optical, physical and chemical properties. But obtaining smooth and damage-free surface on brittle materials by traditional machining methods like grinding, lapping and polishing is very costly and extremely time consuming. Ductile mode cutting is a very promising way to achieve high quality and crack-free surfaces of brittle materials. Thus the study of ductile mode cutting of brittle materials has been attracting more and more efforts. This paper provides an overview of ductile mode cutting of brittle materials including ductile nature and plasticity of brittle materials, cutting mechanism, cutting characteristics, molecular dynamic simulation, critical undeformed chip thickness, brittle-ductile transition, subsurface damage, as well as a detailed discussion of ductile mode cutting enhancement. It is believed that ductile mode cutting of brittle materials could be achieved when both crack-free and no subsurface damage are obtained simultaneously.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, M; Woo, B; Kim, J
Purpose: Objective and reliable quantification of imaging phenotype is an essential part of radiogenomic studies. We compared the reproducibility of two semi-automatic segmentation methods for quantitative image phenotyping in magnetic resonance imaging (MRI) of glioblastoma multiforme (GBM). Methods: MRI examinations with T1 post-gadolinium and FLAIR sequences of 10 GBM patients were downloaded from the Cancer Image Archive site. Two semi-automatic segmentation tools with different algorithms (deformable model and grow cut method) were used to segment contrast enhancement, necrosis and edema regions by two independent observers. A total of 21 imaging features consisting of area and edge groups were extracted automaticallymore » from the segmented tumor. The inter-observer variability and coefficient of variation (COV) were calculated to evaluate the reproducibility. Results: Inter-observer correlations and coefficient of variation of imaging features with the deformable model ranged from 0.953 to 0.999 and 2.1% to 9.2%, respectively, and the grow cut method ranged from 0.799 to 0.976 and 3.5% to 26.6%, respectively. Coefficient of variation for especially important features which were previously reported as predictive of patient survival were: 3.4% with deformable model and 7.4% with grow cut method for the proportion of contrast enhanced tumor region; 5.5% with deformable model and 25.7% with grow cut method for the proportion of necrosis; and 2.1% with deformable model and 4.4% with grow cut method for edge sharpness of tumor on CE-T1W1. Conclusion: Comparison of two semi-automated tumor segmentation techniques shows reliable image feature extraction for radiogenomic analysis of GBM patients with multiparametric Brain MRI.« less
Kaffes, Arthur J; Sriram, Parupudi V J; Rao, Guduru V; Santosh, Darisetti; Reddy, D Nageshwar
2005-11-01
Pre-cutting techniques have been used to gain biliary access at the expense of an increased complication rate. This may be because of the multiple attempts to achieve cannulation by using standard methods before pre-cutting and causing excess edema and papillary trauma. There are limited data on the early use of pre-cutting techniques. We performed a prospective study of the early introduction of needle-knife techniques in patients with difficult biliary cannulation. Standard biliary cannulation was attempted with a sphincterotome and a guidewire. If this failed within 10 minutes or if there were more than 5 pancreatic cannulations, the needle-knife technique was used. Either a standard method of pre-cutting (below-upward) from the papillary orifice or the modified technique of pre-cutting (above-downward), stopping short of the papillary orifice, was adopted, as per the discretion of the endoscopist. If pre-cutting failed, the cannulation was reattempted 24 to 48 hours later. A total of 346 therapeutic biliary ERCP procedures were performed between April and August 2003. Of these, 70 patients (20%) (mean age, 54 years; 38 men) underwent needle-knife pre-cut sphincterotomy (16 with the standard technique). In 58 patients (83%), the procedure was successful with the initial pre-cutting, making the total success at initial ERCP 334/346 (96.5%). Nine patients in whom pre-cut failed, returned for a second-attempt ERCP, with 7 completed successfully. The total success rate of pre-cutting was 65/70 (93%). The overall success rate of biliary cannulation, after two ERCP attempts, was 341/346 (98.5%). Six patients had mild bleeding, and one had mild pancreatitis. There was no difference in these complications between the two types of pre-cut techniques. The early use of needle knife for difficult biliary cannulation is safe and effective, irrespective of the technique used.
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.
Zhang, Lu; Yu, Qingzhao; Wu, Xiao-Cheng; Hsieh, Mei-Chin; Loch, Michelle; Chen, Vivien W; Fontham, Elizabeth; Ferguson, Tekeda
2018-05-01
To investigate the impact of chemotherapy relative dose intensity (RDI) on cause-specific and overall survival for stage I-III breast cancer: estrogen receptor or progesterone receptor positive, human epidermal-growth factor receptor negative (ER+/PR+ and HER2-) vs. triple-negative (TNBC) and to identify the optimal RDI cut-off points in these two patient populations. Data were collected by the Louisiana Tumor Registry for two CDC-funded projects. Women diagnosed with stage I-III ER+/PR+, HER2- breast cancer, or TNBC in 2011 with complete information on RDI were included. Five RDI cut-off points (95, 90, 85, 80, and 75%) were evaluated on cause-specific and overall survival, adjusting for multiple demographic variables, tumor characteristics, comorbidity, use of granulocyte-growth factor/cytokines, chemotherapy delay, chemotherapy regimens, and use of hormone therapy. Cox proportional hazards models and Kaplan-Meier survival curves were estimated and adjusted by stabilized inverse probability treatment weighting (IPTW) of propensity score. Of 494 ER+/PR+, HER2- patients and 180 TNBC patients, RDI < 85% accounted for 30.4 and 27.8%, respectively. Among ER+/PR+, HER2- patients, 85% was the only cut-off point at which the low RDI was significantly associated with worse overall survival (HR = 1.93; 95% CI 1.09-3.40). Among TNBC patients, 75% was the cut-off point at which the high RDI was associated with better cause-specific (HR = 2.64; 95% CI 1.09, 6.38) and overall survival (HR = 2.39; 95% CI 1.04-5.51). Higher RDI of chemotherapy is associated with better survival for ER+/PR+, HER2- patients and TNBC patients. To optimize survival benefits, RDI should be maintained ≥ 85% in ER+/PR+, HER2- patients, and ≥ 75% in TNBC patients.
Method and apparatus for automatically tracking a workpiece surface. [Patents
Not Available
1981-02-03
Laser cutting concepts and apparatus have been developed for cutting the shroud of the core fuel subassemblies. However, much care must be taken in the accuracy of the cutting since the fuel rods within the shroud often become warped and are forced into direct contact with the shroud in random regions. Thus, in order to cut the nuclear fuel rod shroud accurately so as not to puncture the cladding of the fuel rods, and to insure optimal cutting efficiency and performance, the focal point of beam need be maintained accurately at the workpiece surface. It becomes necessary to detect deviations in the level of the workpiece surface accurately in connection with the cutting process. Therefore, a method and apparatus for tracking the surface of a workpiece being cut by a laser beam coming from a focus head assembly is disclosed which includes two collimated laser beams directed onto the work-piece surface at spaced points by beam directing optics in generally parallel planes of incidence. A shift in spacing between the two points is detected by means of a video camera system and processed by a computer to yield a workpiece surface displacement signal which is input to a motor which raises or lowers the beam focus head accordingly.
Root canal centering ability of rotary cutting nickel titanium instruments: A meta-analysis
Gundappa, Mohan; Bansal, Rashmi; Khoriya, Sarvesh; Mohan, Ranjana
2014-01-01
Aim: To systematically review articles on canal centering ability of endodontic rotary cutting Nickel-Titanium (Ni-Ti) instruments and subject results to meta-analysis. Materials and Methods: A comprehensive search was initiated on canal centering ability of different rotary cutting Ni-Ti files such as Protaper, Hero Shaper, K3, Mtwo, Race, Wave One by selecting articles published in peer reviewed journals during 1991-2013 using “Pub Med” database. Inclusion and exclusion criteria were established. A data was created by tabulating: Author name, publication year, sample size, number of experimental groups, methods to evaluate canal centering ability, instrument cross section, taper, tip design, rake angle, mean and standard deviation. The data generated was subjected to meta-analysis. Results: Maximum studies were found to be conducted on mesiobuccal canal of mandibular 1st molar with curvature ranging from 15-60°. The difference in canal centering ability of different rotary cutting Ni-Ti instruments was not statistically significant. Conclusion: All endodontic rotary cutting Ni-Ti instruments are capable of producing centered preparations. Protaper depicted the best centering ability. Computed tomography is an effective method of evaluating canal centering ability. PMID:25506134
On determining the most appropriate test cut-off value: the case of tests with continuous results
Habibzadeh, Parham; Yadollahie, Mahboobeh
2016-01-01
There are several criteria for determination of the most appropriate cut-off value in a diagnostic test with continuous results. Mostly based on receiver operating characteristic (ROC) analysis, there are various methods to determine the test cut-off value. The most common criteria are the point on ROC curve where the sensitivity and specificity of the test are equal; the point on the curve with minimum distance from the left-upper corner of the unit square; and the point where the Youden’s index is maximum. There are also methods mainly based on Bayesian decision analysis. Herein, we show that a proposed method that maximizes the weighted number needed to misdiagnose, an index of diagnostic test effectiveness we previously proposed, is the most appropriate technique compared to the aforementioned ones. For determination of the cut-off value, we need to know the pretest probability of the disease of interest as well as the costs incurred by misdiagnosis. This means that even for a certain diagnostic test, the cut-off value is not universal and should be determined for each region and for each disease condition. PMID:27812299
NASA Astrophysics Data System (ADS)
Yilbas, B. S.; Akhtar, S. S.; Karatas, C.
2017-11-01
A Kevlar laminate has negative thermal expansion coefficient, which makes it difficult to machine at room temperaures using the conventional cutting tools. Contararily, laser machining of a Kevlar laminate provides advantages over the conventional methods because of the non-mechanical contact between the cutting tool and the workpiece. In the present study, laser circular cutting of Kevlar laminate is considered. The experiment is carried out to examine and evaluate the cutting sections. Temperature and stress fields formed in the cutting section are simulated in line with the experimental study. The influence of hole diameters on temperature and stress fields are investigated incorporating two different hole diameters. It is found that the Kevlar laminate cutting section is free from large size asperities such as large scale sideways burnings and attachemnt of charred residues. The maximum temperature along the cutting circumference remains higher for the large diameter hole than that of the small diameter hole. Temperature decay is sharp around the cutting section in the region where the cutting terminates. This, in turn, results in high temperature gradients and the thermal strain in the cutting region. von Mises stress remains high in the region where temperature gradients are high. von Mises stress follows similar to the trend of temperature decay around the cutting edges.
Ortensi, Livia Elisa; Farina, Patrizia; Leye, Els
2018-01-12
Migration flows of women from Female Genital Mutilation/Cutting practicing countries have generated a need for data on women potentially affected by Female Genital Mutilation/Cutting. This paper presents enhanced estimates for foreign-born women and asylum seekers in Italy in 2016, with the aim of supporting resource planning and policy making, and advancing the methodological debate on estimation methods. The estimates build on the most recent methodological development in Female Genital Mutilation/Cutting direct and indirect estimation for Female Genital Mutilation/Cutting non-practicing countries. Direct estimation of prevalence was performed for 9 communities using the results of the survey FGM-Prev, held in Italy in 2016. Prevalence for communities not involved in the FGM-Prev survey was estimated using to the 'extrapolation-of-FGM/C countries prevalence data method' with corrections according to the selection hypothesis. It is estimated that 60 to 80 thousand foreign-born women aged 15 and over with Female Genital Mutilation/Cutting are present in Italy in 2016. We also estimated the presence of around 11 to 13 thousand cut women aged 15 and over among asylum seekers to Italy in 2014-2016. Due to the long established presence of female migrants from some practicing communities Female Genital Mutilation/Cutting is emerging as an issue also among women aged 60 and over from selected communities. Female Genital Mutilation/Cutting is an additional source of concern for slightly more than 60% of women seeking asylum. Reliable estimates on Female Genital Mutilation/Cutting at country level are important for evidence-based policy making and service planning. This study suggests that indirect estimations cannot fully replace direct estimations, even if corrections for migrant socioeconomic selection can be implemented to reduce the bias.
Five Methods for Estimating Angoff Cut Scores with IRT
ERIC Educational Resources Information Center
Wyse, Adam E.
2017-01-01
This article illustrates five different methods for estimating Angoff cut scores using item response theory (IRT) models. These include maximum likelihood (ML), expected a priori (EAP), modal a priori (MAP), and weighted maximum likelihood (WML) estimators, as well as the most commonly used approach based on translating ratings through the test…
Greening the Bottom Line: The Trend toward Green Revolving Funds on Campus
ERIC Educational Resources Information Center
Weisbord, Dano
2011-01-01
Facing steep budget cuts and rising energy costs, many colleges are grappling with how to finance urgently needed, but capital intensive, energy efficiency upgrades on campus. One innovative approach, using return-oriented green revolving funds (GRFs), is a rapidly growing trend at colleges and universities. GRFs can invest in a variety of…
Laminated lumber may be more profitable than sawn lumber
P. Koch
1976-01-01
By laminating 1/4-in. rotary-cut veneer into structural lumber, manufacturers can expand lumber output by at least 30% without increasing volume logged. The idea merits intensive study. Manufacturing plus raw material costs should total about $142/Mbf; sales price for desirable widths and lengths of the strong laminated product should approach or exceed $200/Mbf.
Stand size, stand distribution, and rotation lengths for forest wildlife
Steven E. Backs; Russel R. Titus
1989-01-01
The key to managing forest wildlife is providing diverse habitats. Stand size, stand distribution, and rotation length determine how diverse habitats will be. Since the tenure of private forest owners is generally shorter than prescribed rotations, rotation recommendations serve more as guides to the amount and intensity of cutting needed to maintain desired habitat....
Patrick H. Brose; David H. Van Lear
1998-01-01
Effects of seasonal prescribed fires of varying intensities on density, mortality, stem form, height, and height growth of hardwood advance regeneration were investigated. Three mixed-hardwood stands on productive upland sites were cut using a shelterwood technique, each forming a block of spring burn, summer burn, winter burn, and control treatments. Advance...
Managing the Teacher Workforce: The Consequences of "Last in, First out" Personnel Policies
ERIC Educational Resources Information Center
Goldhaber, Dan; Theobald, Roddy
2011-01-01
Tough economic times mean tight school district budgets, possibly for years to come. Education is a labor-intensive industry, and because most districts devote well over half of all spending to teacher compensation, budget cuts have already led to the most substantial teacher layoffs in recent memory. Although the 2010 federal Education Jobs and…
E.B. Schilling; B.G. Lockaby; Robert Rummer
1999-01-01
Abstract: The influence of clear and partial cut harvests on belowground nutrient cycling processes was examined on the Pearl River floodplain, Mississippi. Foci examined by this study included fine root biomass and detritus, fine root production, fine root nutrient contents, soil respiration rates, and microbial biomass C, N, and P during the first...
Oak Ecosystem Restoration and Maintenance in Southern Illinois
Charles M. Ruffner; John W. Groninger
2004-01-01
Oak dominance in southern Illinois appears to be a consequence of long term anthropogenic disturbances, including burning, grazing, and cutting. The increased prevalence of thin barked, shade tolerant species, such as sugar maple and beech on presently oak-dominated upland sites appears to be a result of the extremely low-intensity distur-bance regimes of the late 20...
Air Pollution, Acid Rain, and the Future of Forests. Worldwatch Paper 58.
ERIC Educational Resources Information Center
Postel, Sandra
This book traces centuries of human use and abuse of forest ecosystems by discussing past decades of intense burning, grazing, and timber cutting that added to the natural acidification of the soil. Air pollutants and acids generated by industrial activities worldwide are also considered. Many forests in Europe and North America now receive as…
From the Rio to the Sierra: An environmental history of the Middle Rio Grande Basin
Dan Scurlock
1998-01-01
Various human groups have greatly affected the processes and evolution of Middle Rio Grande Basin ecosystems, especially riparian zones, from A.D. 1540 to the present. Overgrazing, clear-cutting, irrigation farming, fire suppression, intensive hunting, and introduction of exotic plants have combined with droughts and floods to bring about environmental and associated...
Slash disposal in oak-pine stands of southern New Jersey
S. Little; H. A. Somes
1949-01-01
Slash left from cutting operations in forest stands may have several important economic effects. It may kill established reproduction or provide unfavorable conditions for the establishment of new seedlings, thus preventing the restocking of the area with a desirable crop of timber. Slash may also create a serious fire hazard, providing fuel for intense fires that are...
Output-Adaptive Tetrahedral Cut-Cell Validation for Sonic Boom Prediction
NASA Technical Reports Server (NTRS)
Park, Michael A.; Darmofal, David L.
2008-01-01
A cut-cell approach to Computational Fluid Dynamics (CFD) that utilizes the median dual of a tetrahedral background grid is described. The discrete adjoint is also calculated, which permits adaptation based on improving the calculation of a specified output (off-body pressure signature) in supersonic inviscid flow. These predicted signatures are compared to wind tunnel measurements on and off the configuration centerline 10 body lengths below the model to validate the method for sonic boom prediction. Accurate mid-field sonic boom pressure signatures are calculated with the Euler equations without the use of hybrid grid or signature propagation methods. Highly-refined, shock-aligned anisotropic grids were produced by this method from coarse isotropic grids created without prior knowledge of shock locations. A heuristic reconstruction limiter provided stable flow and adjoint solution schemes while producing similar signatures to Barth-Jespersen and Venkatakrishnan limiters. The use of cut-cells with an output-based adaptive scheme completely automated this accurate prediction capability after a triangular mesh is generated for the cut surface. This automation drastically reduces the manual intervention required by existing methods.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pasquariello, Vito, E-mail: vito.pasquariello@tum.de; Hammerl, Georg; Örley, Felix
2016-02-15
We present a loosely coupled approach for the solution of fluid–structure interaction problems between a compressible flow and a deformable structure. The method is based on staggered Dirichlet–Neumann partitioning. The interface motion in the Eulerian frame is accounted for by a conservative cut-cell Immersed Boundary method. The present approach enables sub-cell resolution by considering individual cut-elements within a single fluid cell, which guarantees an accurate representation of the time-varying solid interface. The cut-cell procedure inevitably leads to non-matching interfaces, demanding for a special treatment. A Mortar method is chosen in order to obtain a conservative and consistent load transfer. Wemore » validate our method by investigating two-dimensional test cases comprising a shock-loaded rigid cylinder and a deformable panel. Moreover, the aeroelastic instability of a thin plate structure is studied with a focus on the prediction of flutter onset. Finally, we propose a three-dimensional fluid–structure interaction test case of a flexible inflated thin shell interacting with a shock wave involving large and complex structural deformations.« less
Dong, Jianwu; Chen, Feng; Zhou, Dong; Liu, Tian; Yu, Zhaofei; Wang, Yi
2017-03-01
Existence of low SNR regions and rapid-phase variations pose challenges to spatial phase unwrapping algorithms. Global optimization-based phase unwrapping methods are widely used, but are significantly slower than greedy methods. In this paper, dual decomposition acceleration is introduced to speed up a three-dimensional graph cut-based phase unwrapping algorithm. The phase unwrapping problem is formulated as a global discrete energy minimization problem, whereas the technique of dual decomposition is used to increase the computational efficiency by splitting the full problem into overlapping subproblems and enforcing the congruence of overlapping variables. Using three dimensional (3D) multiecho gradient echo images from an agarose phantom and five brain hemorrhage patients, we compared this proposed method with an unaccelerated graph cut-based method. Experimental results show up to 18-fold acceleration in computation time. Dual decomposition significantly improves the computational efficiency of 3D graph cut-based phase unwrapping algorithms. Magn Reson Med 77:1353-1358, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
Lexan Linear Shaped Charge Holder with Magnets and Backing Plate
NASA Technical Reports Server (NTRS)
Maples, Matthew W.; Dutton, Maureen L.; Hacker, Scott C.; Dean, Richard J.; Kidd, Nicholas; Long, Chris; Hicks, Robert C.
2013-01-01
A method was developed for cutting a fabric structural member in an inflatable module, without damaging the internal structure of the module, using linear shaped charge. Lexan and magnets are used in a charge holder to precisely position the linear shaped charge over the desired cut area. Two types of charge holders have been designed, each with its own backing plate. One holder cuts fabric straps in the vertical configuration, and the other charge holder cuts fabric straps in the horizontal configuration.
NASA Astrophysics Data System (ADS)
Apel, W. D.; Arteaga-Velázquez, J. C.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Fuhrmann, D.; Gherghel-Lascu, A.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huber, D.; Huege, T.; Kampert, K.-H.; Kang, D.; Klages, H. O.; Link, K.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Oehlschläger, J.; Ostapchenko, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schoo, S.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Zabierowski, J.
2016-04-01
The energy reconstruction at KASCADE-Grande is based on a combination of the shower size and the total muon number, which are both estimated for each individual air shower event. We present investigations where we employed a second method to reconstruct the primary energy using S(500), which are the charged particle densities inferred with the KASCADE-Grande detector at a distance of 500 m from the shower axis. We considered the attenuation of inclined showers by applying the "Constant Intensity Cut" method and we employed a simulation-derived calibration to convert the recorded S(500) into primary energy. We observed a systematic shift in the S(500)-derived energy compared with previously reported results obtained using the standard reconstruction technique. However, a comparison of the two methods based on simulated and measured data showed that this shift only appeared in the measured data. Our investigations showed that this shift was caused mainly by the inadequate description of the shape of the lateral density distribution in the simulations.
Numerical simulation and comparison of nonlinear self-focusing based on iteration and ray tracing
NASA Astrophysics Data System (ADS)
Li, Xiaotong; Chen, Hao; Wang, Weiwei; Ruan, Wangchao; Zhang, Luwei; Cen, Zhaofeng
2017-05-01
Self-focusing is observed in nonlinear materials owing to the interaction between laser and matter when laser beam propagates. Some of numerical simulation strategies such as the beam propagation method (BPM) based on nonlinear Schrödinger equation and ray tracing method based on Fermat's principle have applied to simulate the self-focusing process. In this paper we present an iteration nonlinear ray tracing method in that the nonlinear material is also cut into massive slices just like the existing approaches, but instead of paraxial approximation and split-step Fourier transform, a large quantity of sampled real rays are traced step by step through the system with changing refractive index and laser intensity by iteration. In this process a smooth treatment is employed to generate a laser density distribution at each slice to decrease the error caused by the under-sampling. The characteristics of this method is that the nonlinear refractive indices of the points on current slice are calculated by iteration so as to solve the problem of unknown parameters in the material caused by the causal relationship between laser intensity and nonlinear refractive index. Compared with the beam propagation method, this algorithm is more suitable for engineering application with lower time complexity, and has the calculation capacity for numerical simulation of self-focusing process in the systems including both of linear and nonlinear optical media. If the sampled rays are traced with their complex amplitudes and light paths or phases, it will be possible to simulate the superposition effects of different beam. At the end of the paper, the advantages and disadvantages of this algorithm are discussed.
Evaluation of laser ablation microtomy for correlative microscopy of hard tissues.
Boyde, A
2018-02-27
Laser ablation machining or microtomy (LAM) is a relatively new approach to producing slide mounted sections of translucent materials. We evaluated the method with a variety of problems from the bone, joint and dental tissues fields where we require thin undecalcified and undistorted sections for correlative light microscopy (LM) and backscattered electron scanning electron microscopy (BSE SEM). All samples were embedded in poly-methylmethacrlate (PMMA) and flat block surfaces had been previously studied by BSE-SEM and confocal scanning light microscopy (CSLM). Most were also studied by X-yay microtomography (XMT). The block surface is stuck to a glass slide with cyanoacrylate adhesive. Setting the section thickness and levelling uses inbuilt optical coherence tomographic imaging. Tight focusing of near-infrared laser radiation in the sectioning plane gives extreme intensities causing photodisruption of material at the focal point. The laser beam is moved by a fast scanner to write a cutting line, which is simultaneously moved by an XY positioning unit to create a sectioning plane. The block is thereby released from the slide, leaving the section stuck to the slide. Light, wet polishing on the finest grade (4000 grit) silicon carbide polishing paper is used to remove a 1-2 μm thick damaged layer at the surface of the section. Sections produced by laser cutting are fine in quality and superior to those produced by mechanical cutting and can be thinner than the 'voxel' in most laboratory X-ray microtomography systems. The present extensive pilot studies have shown that it works to produce samples which we can study by both light and electron microscopy. © 2018 The Authors Journal of Microscopy © 2018 Royal Microscopical Society.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dong, S. L.; Lin, H. H., E-mail: linhh@hstc.edu.cn, E-mail: qyzhang@scut.edu.cn; Yu, T.
2014-07-14
The phosphors Ca{sub 3}(PO{sub 4}){sub 2}:Tm{sup 3+} by co-doping Ce{sup 3+} have been synthesized by conventional high-temperature solid-state reaction method. Their spectroscopic properties in the UV-VIS-NIR range have been investigated. The first 5d crystal field level location and stokes shift have been determined from the UV excitation and emission spectra of Ca{sub 3}(PO{sub 4}){sub 2}:Ce{sup 3+}. The three-photon NIR quantum-cutting luminescence of Tm{sup 3+} assigned to the electronic transitions of {sup 1}G{sub 4}→{sup 3}H{sub 4}, {sup 3}H{sub 4}→{sup 3}F{sub 4} and {sup 3}F{sub 4}→{sup 3}H{sub 6} is observed, whether in Ca{sub 3}(PO{sub 4}){sub 2}:Tm{sup 3+} or Ca{sub 3}(PO{sub 4}){sub 2}:Tm{supmore » 3+},Ce{sup 3+}. The energy transfer from Ce{sup 3+} to Tm{sup 3+} takes place with energy-transfer efficiency up to 34.5% for the Ca{sub 3}(PO{sub 4}){sub 2}:Tm{sup 3+},Ce{sup 3+}. A cross relaxation scheme using the 5d states of Ce{sup 3+} and f-f transition of Tm{sup 3+} is proposed. The mechanism is revealed from energy level and decay measurements. The results show that the broadband absorption of Ce{sup 3+} sensitizer not only extends the spectrum conversion in UV region but also greatly enhances the photoluminescence intensities of the three-photon quantum cutting luminescence of Tm{sup 3+} doped Ca{sub 3}(PO{sub 4}){sub 2}.« less
... such as redness, swelling, pain, or drainage. Wire cutting method: First, wash your hands with soap and ... is casting. Keep electrician's pliers with a wire-cutting blade and disinfecting solution in your tackle box. ...
[Improvement of magnetic resonance phase unwrapping method based on Goldstein Branch-cut algorithm].
Guo, Lin; Kang, Lili; Wang, Dandan
2013-02-01
The phase information of magnetic resonance (MR) phase image can be used in many MR imaging techniques, but phase wrapping of the images often results in inaccurate phase information and phase unwrapping is essential for MR imaging techniques. In this paper we analyze the causes of errors in phase unwrapping with the commonly used Goldstein Brunch-cut algorithm and propose an improved algorithm. During the unwrapping process, masking, filtering, dipole- remover preprocessor, and the Prim algorithm of the minimum spanning tree were introduced to optimize the residues essential for the Goldstein Brunch-cut algorithm. Experimental results showed that the residues, branch-cuts and continuous unwrapped phase surface were efficiently reduced and the quality of MR phase images was obviously improved with the proposed method.
NASA Astrophysics Data System (ADS)
Lawal, S. A.; Choudhury, I. A.; Nukman, Y.
2015-01-01
The understanding of cutting fluids performance in turning process is very important in order to improve the efficiency of the process. This efficiency can be determined based on certain process parameters such as flank wear, cutting forces developed, temperature developed at the tool chip interface, surface roughness on the work piece, etc. In this study, the objective is to determine the influence of cutting fluids on flank wear during turning of AISI 4340 with coated carbide inserts. The performances of three types of cutting fluids were compared using Taguchi experimental method. The results show that palm kernel oil based cutting fluids performed better than the other two cutting fluids in reducing flank wear. Mathematical models for cutting parameters such as cutting speed, feed rate, depth of cut and cutting fluids were obtained from regression analysis using MINITAB 14 software to predict flank wear. Experiments were conducted based on the optimized values to validate the regression equations for flank wear and 5.82 % error was obtained. The optimal cutting parameters for the flank wear using S/N ratio were 160 m/min of cutting speed (level 1), 0.18 mm/rev of feed (level 1), 1.75 mm of depth of cut (level 2) and 2.97 mm2/s palm kernel oil based cutting fluid (level 3). ANOVA shows cutting speed of 85.36 %; and feed rate 4.81 %) as significant factors.
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.
Zhang, Ju-qiong; Lin, Hai-ming; Lin, Nan
2011-07-01
To study the effect of plastic film covering, straw covering, plastic film covering in greenhouse and no-covering cutting on growth and Chlorophyll content of Lycium barbarum hardwood cutting seedlings. Single factor randomized block design method was used in this research. The effect of different covering treatments on germination rate, seedling rate and growth potential were all plastic film covering in greenhouse > plastic film covering > straw covering > no-covering cutting. Chlorophyll a, Chlorophyll b, Chlorophyll a + b content and Ca/Cb were significantly different with different coverings in different periods. The optimal covering on hardwood cutting of Lycium barbarum is plastic film covering in greenhouse. Both plastic film and straw covering are better than no-covering cutting.
Optimum wall impedance for spinning modes: A correlation with mode cut-off ratio
NASA Technical Reports Server (NTRS)
Rice, E. J.
1978-01-01
A correlating equation relating the optimum acoustic impedance for the wall lining of a circular duct to the acoustic mode cut-off ratio, is presented. The optimum impedance was correlated with cut-off ratio because the cut-off ratio appears to be the fundamental parameter governing the propagation of sound in the duct. Modes with similar cut-off ratios respond in a similar way to the acoustic liner. The correlation is a semi-empirical expression developed from an empirical modification of an equation originally derived from sound propagation theory in a thin boundary layer. This correlating equation represents a part of a simplified liner design method, based upon modal cut-off ratio, for multimodal noise propagation.
Fiber optic submarine cables cuts cost modeling and cable protection aspects
NASA Astrophysics Data System (ADS)
Al-Lawati, Ali
2015-03-01
This work presents a model to calculate costs associated with submarine fiber optic cable cuts. It accounts for both fixed and variable factors determining cost of fixing cables and restoring data transmission. It considers duration of a cut, capacity of fibers, number of fiber pairs and expected number of cuts during cable life time. Moreover, it provides templates for initial feasibility assessments by comparing cut costs to cost of different cable protection schemes. It offers a needed tool to assist in guiding decision makers in selecting type of cable, length and depth of cable burial in terms of increase in initial investment due to adapting such protection methods, and compare it to cost of cuts repair and alternative restoration paths for data.
Nanoplasmonic generation of ultrashort EUV pulses
NASA Astrophysics Data System (ADS)
Choi, Joonhee; Lee, Dong-Hyub; Han, Seunghwoi; Park, In-Yong; Kim, Seungchul; Kim, Seung-Woo
2012-10-01
Ultrashort extreme-ultraviolet (EUV) light pulses are an important tool for time-resolved pump-probe spectroscopy to investigate the ultrafast dynamics of electrons in atoms and molecules. Among several methods available to generate ultrashort EUV light pulses, the nonlinear frequency upconversion process of high-harmonic generation (HHG) draws attention as it is capable of producing coherent EUV pulses with precise control of burst timing with respect to the driving near-infrared (NIR) femtosecond laser. In this report, we present and discuss our recent experimental data obtained by the plasmon-driven HHG method that generate EUV radiation by means of plasmonic nano-focusing of NIR femtosecond pulses. For experiment, metallic waveguides having a tapered hole of funnel shape inside were fabricated by adopting the focused-ion-beam process on a micro-cantilever substrate. The plasmonic field formed within the funnelwaveguides being coupled with the incident femtosecond pulse permitted intensity enhancement by a factor of ~350, which creates a hot spot of sub-wavelength size with intensities strong enough for HHG. Experimental results showed that with injection of noble gases into the funnel-waveguides, EUV radiation is generated up to wavelengths of 32 nm and 29.6 nm from Ar and Ne gas atoms, respectively. Further, it was observed that lower-order EUV harmonics are cut off in the HHG spectra by the tiny exit aperture of the funnel-waveguide.
Production of a high-velocity water slug using an impacting technique.
Dehkhoda, S; Bourne, N K
2014-02-01
A pulsed water jet consists of a series of discrete water slugs travelling at high velocity. Immediately after striking a target, these slugs apply high-intensity, short-duration transient stress pulses reaching an amplitude known as the water hammer pressure, followed by low-intensity, long-duration stationary stress at a lower stagnation pressure. The magnitude and duration of the water hammer and stagnation pressures are controlled by the size and quality of the water slugs. The use of water jets for rock cutting in mining operations is a centuries-old technology; however, practical methods for producing high-energy water slugs repeatedly have proven difficult. This can be partly due to the fact that the geometrical properties of a jet and so its effectiveness in creating damage is controlled and influenced by the method that is employed to generate the water slugs. This paper investigates the quality of a single water slug produced using an impacting technique where a hammer strikes a piston, resting on top of a water-filled chamber. The coherence and integrity of the jet core was of concern in this study. The impact impulse of the formed water jet was measured in a Kel-F target material using an embedded PVDF (Polyvinylidene fluoride) shock gauge. The recorded stress waveform was then used to determine the unity and endurance of the water slug stream once travelled through air.
Production of a high-velocity water slug using an impacting technique
NASA Astrophysics Data System (ADS)
Dehkhoda, S.; Bourne, N. K.
2014-02-01
A pulsed water jet consists of a series of discrete water slugs travelling at high velocity. Immediately after striking a target, these slugs apply high-intensity, short-duration transient stress pulses reaching an amplitude known as the water hammer pressure, followed by low-intensity, long-duration stationary stress at a lower stagnation pressure. The magnitude and duration of the water hammer and stagnation pressures are controlled by the size and quality of the water slugs. The use of water jets for rock cutting in mining operations is a centuries-old technology; however, practical methods for producing high-energy water slugs repeatedly have proven difficult. This can be partly due to the fact that the geometrical properties of a jet and so its effectiveness in creating damage is controlled and influenced by the method that is employed to generate the water slugs. This paper investigates the quality of a single water slug produced using an impacting technique where a hammer strikes a piston, resting on top of a water-filled chamber. The coherence and integrity of the jet core was of concern in this study. The impact impulse of the formed water jet was measured in a Kel-F target material using an embedded PVDF (Polyvinylidene fluoride) shock gauge. The recorded stress waveform was then used to determine the unity and endurance of the water slug stream once travelled through air.
Froud, Robert; Abel, Gary
2014-01-01
Background Receiver Operator Characteristic (ROC) curves are being used to identify Minimally Important Change (MIC) thresholds on scales that measure a change in health status. In quasi-continuous patient reported outcome measures, such as those that measure changes in chronic diseases with variable clinical trajectories, sensitivity and specificity are often valued equally. Notwithstanding methodologists agreeing that these should be valued equally, different approaches have been taken to estimating MIC thresholds using ROC curves. Aims and objectives We aimed to compare the different approaches used with a new approach, exploring the extent to which the methods choose different thresholds, and considering the effect of differences on conclusions in responder analyses. Methods Using graphical methods, hypothetical data, and data from a large randomised controlled trial of manual therapy for low back pain, we compared two existing approaches with a new approach that is based on the addition of the sums of squares of 1-sensitivity and 1-specificity. Results There can be divergence in the thresholds chosen by different estimators. The cut-point selected by different estimators is dependent on the relationship between the cut-points in ROC space and the different contours described by the estimators. In particular, asymmetry and the number of possible cut-points affects threshold selection. Conclusion Choice of MIC estimator is important. Different methods for choosing cut-points can lead to materially different MIC thresholds and thus affect results of responder analyses and trial conclusions. An estimator based on the smallest sum of squares of 1-sensitivity and 1-specificity is preferable when sensitivity and specificity are valued equally. Unlike other methods currently in use, the cut-point chosen by the sum of squares method always and efficiently chooses the cut-point closest to the top-left corner of ROC space, regardless of the shape of the ROC curve. PMID:25474472
Quartz crystal resonator g sensitivity measurement methods and recent results.
Driscoll, M M
1990-01-01
A technique for accurate measurements of quartz crystal resonator vibration sensitivity is described. The technique utilizes a crystal oscillator circuit in which a prescribed length of coaxial cable is used to connect the resonator to the oscillator sustaining stage. A method is provided for determination and removal of measurement errors normally introduced as a result of cable vibration. In addition to oscillator-type measurements, it is also possible to perform similar vibration sensitivity measurements using a synthesized signal generator with the resonator installed in a passive phase bridge. Test results are reported for 40 and 50 MHz, fifth overtone AT-cut, and third overtone SC-cut crystals. Acceleration sensitivity (gamma vector) values for the SC-cut resonators were typically four times smaller (5x10(-10) per g) than for the AT-cut units. However, smaller unit-to-unit gamma vector magnitude variation was exhibited by the AT-cut resonators. Oscillator sustaining stage vibration sensitivity was characterized by an equivalent open-loop phase modulation of 10(-6) rad/g.
Detection of Cutting Tool Wear using Statistical Analysis and Regression Model
NASA Astrophysics Data System (ADS)
Ghani, Jaharah A.; Rizal, Muhammad; Nuawi, Mohd Zaki; Haron, Che Hassan Che; Ramli, Rizauddin
2010-10-01
This study presents a new method for detecting the cutting tool wear based on the measured cutting force signals. A statistical-based method called Integrated Kurtosis-based Algorithm for Z-Filter technique, called I-kaz was used for developing a regression model and 3D graphic presentation of I-kaz 3D coefficient during machining process. The machining tests were carried out using a CNC turning machine Colchester Master Tornado T4 in dry cutting condition. A Kistler 9255B dynamometer was used to measure the cutting force signals, which were transmitted, analyzed, and displayed in the DasyLab software. Various force signals from machining operation were analyzed, and each has its own I-kaz 3D coefficient. This coefficient was examined and its relationship with flank wear lands (VB) was determined. A regression model was developed due to this relationship, and results of the regression model shows that the I-kaz 3D coefficient value decreases as tool wear increases. The result then is used for real time tool wear monitoring.
Vapor-melt Ratio in Laser Fine Cutting of Slot Arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang Xuyue; Meng Qingxuan; Kang Renke
In order to improve cut quality for slot arrays, a new method of laser fine cutting under the consideration of the ratio of vapor to melt is presented. Laser cutting of 6063 aluminum alloy sheet, 0.5 mm in thickness, was carried out on a JK701H Nd:YAG pulse laser cutting system. The effects of vapor-melt ratio on kerf width, surface roughness and recast layer were studied which relate cutting qualities. Observation on the cut samples with different vapor-melt ratios (0.687, 1.574, 3.601 varied with laser power increasing, and 1.535, 3.601, 7.661 with decreasing of beam cutting speed) shows that high vapor-meltmore » ratio improves laser cut quality clearly. Kerf width 0.2 mm of smooth area on kerf top area and thickness 2.03 {mu}m of recast layer are obtained. No dross was found on the kerf bottom and the percentage of the smooth area is up to 40% out of whole kerf side. The research on vapor-melt ratio provides a deeper understanding of laser cutting and improves laser cut quality effectively.« less
Distribution of contact loads over the flank-land of the cutter with a rounded cutting edge
NASA Astrophysics Data System (ADS)
Kozlov, V.; Gerasimov, A.; Kim, A.
2016-04-01
In this paper, contact conditions between a tool and a workpiece material for wear-simulating turning by a cutter with a sharp-cornered edge and with a rounded cutting edge are analysed. The results of the experimental study of specific contact load distribution over the artificial flank wear-land of the cutter in free orthogonal turning of the disk from titanium alloy (Ti6Al2Mo2Cr), ductile (63Cu) and brittle (57Cu1Al3Mn) brasses are described. Investigations were carried out by the method of ‘split cutter’ and by the method of the artificial flank-land of variable width. The experiments with a variable feed rate and a cutting speed show that in titanium alloy machining with a sharp-cornered cutting edge the highest normal contact load (σh max = 3400…2200 MPa) is observed immediately at the cutting edge, and the curve has a horizontal region with the length of 0.2… 0.6 mm. At a distance from the cutting edge, the value of specific normal contact load is dramatically reduced to 1100…500 MPa. The character of normal contact load for a rounded cutting edge is different -it is uniform, and its value is approximately 2 times smaller compared to machining with a sharp-cornered cutting edge. In author’s opinion it is connected with generation of a seizure zone in a chip formation region and explains the capacity of highly worn-out cutting tools for titanium alloys machining. The paper analyses the distribution of tangential contact loads over the flank land, which pattern differs considerably for machining with a sharp-cornered edge and with a rounded cutting edge. Abbreviation and symbols: m/s - meter per second (cutting speed v); mm/r - millimeter per revolution (feed rate f); MPa - mega Pascal (specific contact load as a stress σ or τ) hf - the width of the flank wear land (chamfer) of the cutting tool, flank wear land can be natural or artificial like the one in this paper [mm]; xh - distance from the cutting edge on the surface of the flank-land [mm]; σh - normal specific contact load on the flank land [MPa]; τh - tangential (shear) specific contact load on the flank land [MPa]; HSS - high speed steel (material of cutting tool); Py - radial component of cutting force [N]; Py r - radial component of cutting force on the rake face [N]; Pz - tangential component of cutting force [N]; γ - rake angle of the cutting tool [°] α - clearance angle of the sharp cutting tool [°] αh - clearance angle of the flank wear land [°] ρ - rounding off radius of the cutting edge [mm]; b - width of the machined disk [mm].
Apparatus for preparing cornea material for tabbed (sutureless) transplantation
Collins, Joseph Patrick
1997-01-01
A tool and a method for preparing a donor material used in sutureless corneal transplants uses a first cutting portion to prepare a donor blank having tabbed portions extending outwardly radially. A second cutting portion is used to cut the central portion of the blank. The tool is used as a guide member for the second cutting portion. In one embodiment the tool has slits laterally defined therethrough which allow the tabbed portions of the donor material to be thinned to a desired thickness using a scalpel. In an another embodiment the second cutting portion is a round trephine which is used to simultaneously trim each of the tabbed portions.
Hypervelocity cutting machine and method
Powell, James R.; Reich, Morris
1996-11-12
A method and machine 14 are provided for cutting a workpiece 12 such as concrete. A gun barrel 16 is provided for repetitively loading projectiles 22 therein and is supplied with a pressurized propellant from a storage tank 28. A thermal storage tank 32,32A is disposed between the propellant storage tank 28 and the gun barrel 16 for repetitively receiving and heating propellant charges which are released in the gun barrel 16 for repetitively firing projectiles 22 therefrom toward the workpiece 12. In a preferred embodiment, hypervelocity of the projectiles 22 is obtained for cutting the concrete workpiece 12 by fracturing thereof.
In-situ stabilization of radioactive zirconium swarf
Hess, C.C.
1999-08-31
The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes. 6 figs.
Computer numeric control generation of toric surfaces
NASA Astrophysics Data System (ADS)
Bradley, Norman D.; Ball, Gary A.; Keller, John R.
1994-05-01
Until recently, the manufacture of toric ophthalmic lenses relied largely upon expensive, manual techniques for generation and polishing. Recent gains in computer numeric control (CNC) technology and tooling enable lens designers to employ single- point diamond, fly-cutting methods in the production of torics. Fly-cutting methods continue to improve, significantly expanding lens design possibilities while lowering production costs. Advantages of CNC fly cutting include precise control of surface geometry, rapid production with high throughput, and high-quality lens surface finishes requiring minimal polishing. As accessibility and affordability increase within the ophthalmic market, torics promise to dramatically expand lens design choices available to consumers.
A new method to measure circular runout of end-milling spindle based on cutting mark
NASA Astrophysics Data System (ADS)
Zhou, Jianlai; Liu, Shuchun
2008-12-01
A practical method is introduced to measure the circular runout of a end-milling spindle system at high speed rotations without the need of a reference sphere. A workpiece is held on a linear slide which moves along the axial direction of the spindle. The spindle is then programmed to run at a specific speed. A very sharp edge cutter must be used and the depth of cut will be very shallow in order to keep the cutting force very small. The workpiece is then fed into the end mill in order to make a cutting mark of teens μm in depth. The cutting marks are circular, and their diameters are related to the circular runout of the spindle system. The cutting mark that is generated at a specific speed is expected to contain information about the spindle circular runout at this speed. In practice the cutting marks are not perfectly circular. Therefore, a best-fit circle of a cutting mark is needed to determine its diameter. A high-resolution edge detector machine is used for this purpose. Quantitative precision analysis was carried out to confirm the accuracy and repeatability of this new measurement technique. It is demonstrated that this technique for the measurement of spindle circular runout is an effective tool in verifying the actual running accuracy of spindles at their actual operating speeds and can be accomplished without the need for a reference sphere.
Economics of cutting hardwood dimension parts with an automated system
Henry A. Huber; Steve Ruddell; Kalinath Mukherjee; Charles W. McMillin
1989-01-01
A financial analysis using discounted cash-flow decision methods was completed to determine the economic feasibility of replacing a conventional roughmill crosscut and rip operation with a proposed automated computer vision and laser cutting system. Red oak and soft maple lumber were cut at production levels of 30 thousand board feet (MBF)/day and 5 MBF/day to produce...
Vogt, Sonja; Efferson, Charles; Fehr, Ernst
2017-12-01
Worldwide, an estimated 200 million girls and women have been subjected to female genital cutting. Female genital cutting is defined as an intentional injury to the female genitalia without medical justification. The practice occurs in at least 29 countries in Africa, the Middle East, and Asia. In addition, globalization and migration have brought immigrants from countries where cutting is commonly practiced to countries where cutting is not traditionally practiced and may even be illegal. In countries receiving immigrants, governments and development agencies would like to know if girls with parents who immigrated from practicing countries are at risk of being cut. Risk assessments, for example, could help governments identify the need for programs promoting the abandonment of cutting among immigrants. Extrapolating from the prevalence and incidence rates in practicing countries, however, is generally not sufficient to guarantee a valid estimate of risk in immigrant populations. In particular, immigrants might differ from their counterparts in the country of origin in terms of attitudes toward female genital cutting. Attitudes can differ because migrants represent a special sample of people from the country of origin or because immigrants acculturate after arriving in a new country. To examine these possibilities, we used a fully anonymous, computerized task to elicit implicit attitudes toward female genital cutting among Sudanese immigrants living in Switzerland and Sudanese people in Sudan. Results show that Sudanese immigrants in Switzerland were significantly more positive about uncut girls than Sudanese in Sudan, and that selective migration out of Sudan likely contributed substantially to this difference. We conclude by suggesting how our method could potentially be coupled with recent efforts to refine extrapolation methods for estimating cutting risk among immigrant populations. More broadly, our results highlight the need to better understand how heterogeneous attitudes can affect the risk of cutting among immigrant communities and in countries of origin.
New Design Heaters Using Tubes Finned by Deforming Cutting Method
NASA Astrophysics Data System (ADS)
Zubkov, N. N.; Nikitenko, S. M.; Nikitenko, M. S.
2017-10-01
The article describes the results of research aimed at selecting and assigning technological processing parameters for obtaining outer fins of heat-exchange tubes by the deformational cutting method, for use in a new design of industrial water-air heaters. The thermohydraulic results of comparative engineering tests of new and standard design air-heaters are presented.
Repairing Hard-to-Reach Cracks in Heat-Exchanger Tubes
NASA Technical Reports Server (NTRS)
Mills, R. C., Sr.; Duesberg, J.
1986-01-01
Inaccessible leaks repaired from accessible side of tube. Fish-Mouth insert placed in cut in leaky heat-exchanger tube. Insert welded or brazed to tube, and remaining open area of cut patched. Method developed for repairing leaks in nozzle coolant tubes of Space Shuttle main engine. Method also used on other types of tubular heat exchangers.
Method and apparatus for jet-assisted drilling or cutting
Summers, David Archibold; Woelk, Klaus Hubert; Oglesby, Kenneth Doyle; Galecki, Grzegorz
2012-09-04
An abrasive cutting or drilling system, apparatus and method, which includes an upstream supercritical fluid and/or liquid carrier fluid, abrasive particles, a nozzle and a gaseous or low-density supercritical fluid exhaust abrasive stream. The nozzle includes a throat section and, optionally, a converging inlet section, a divergent discharge section, and a feed section.
Method and apparatus for jet-assisted drilling or cutting
Summers, David Archibold; Woelk, Klaus Hubert; Oglesby, Kenneth Doyle; Galecki, Grzegorz
2013-07-02
An abrasive cutting or drilling system, apparatus and method, which includes an upstream supercritical fluid and/or liquid carrier fluid, abrasive particles, a nozzle and a gaseous or low-density supercritical fluid exhaust abrasive stream. The nozzle includes a throat section and, optionally, a converging inlet section, a divergent discharge section, and a feed section.
1978-08-01
12°±30’ 1180±2° OPTIONAL .0005 IN./IN. BACK TAPER 015 RAD LIPS TO BE WITHIN .002 OF TRUE ANGULAR POSITION NOTES: 1. LAND WIDTH: 28% ± .005... horoscope and dye-penetrant requirements. 79 PHASE 1 PHASE II PHASE III PHASE IV CUTTING DRILLING MACHINING NONDESTRUCTIVE EVALUATION METHOD MATERIAL
Schlesinger, E R; Skoner, M M; Trooskin, E D; Markel, J R; North, A F
1976-04-01
A questionnaire survey of Title V special projects--Maternal and Infant Care (M&I), Comprehensive Care for Children and Youth (C&Y), Neonatal Intensive Care and Children's Dental Care--indicated that the anticipated change from federal project grants to state formula grants caused anxiety among project directors, low morale and high turnover in project staff, difficulty in filling staff positions, and anticipation of service reductions. These effects were much more prevalent and severe in projects which could realistically be expected to suffer budget cuts as a result of the shift in funding method. Despite the widespread anxiety, low morale and adverse effects reported by program directors, there was no reduction in the number of patients served, the scope of services offered, or the number of staff employed.
Sensory Characterization of Odors in Used Disposable Absorbent Incontinence Products
Widén, Heléne; Forsgren-Brusk, Ulla; Hall, Gunnar
2017-01-01
PURPOSE: The objectives of this study were to characterize the odors of used incontinence products by descriptive analysis and to define attributes to be used in the analysis. A further objective was to investigate to what extent the odor profiles of used incontinence products differed from each other and, if possible, to group these profiles into classes. SUBJECTS AND SETTING: Used incontinence products were collected from 14 residents with urinary incontinence living in geriatric nursing homes in the Gothenburg area, Sweden. METHODS: Pieces were cut from the wet area of used incontinence products. They were placed in glass bottles and kept frozen until odor analysis was completed. A trained panel consisting of 8 judges experienced in this area of investigation defined terminology for odor attributes. The intensities of these attributes in the used products were determined by descriptive odor analysis. Data were analyzed both by analysis of variance (ANOVA) followed by the Tukey post hoc test and by principal component analysis and cluster analysis. RESULTS: An odor wheel, with 10 descriptive attributes, was developed. The total odor intensity, and the intensities of the attributes, varied considerably between different, used incontinence products. The typical odors varied from “sweetish” to “urinal,” “ammonia,” and “smoked.” Cluster analysis showed that the used products, based on the quantitative odor data, could be divided into 5 odor classes with different profiles. CONCLUSIONS: The used products varied considerably in odor character and intensity. Findings suggest that odors in used absorptive products are caused by different types of compounds that may vary in concentration. PMID:28328646
Kuusisto, N; Vallittu, P K; Lassila, L V J
2015-01-01
Objectives: The aim was to compare the intensity of artefacts in CBCT images caused by different percentages of radio-opacifying material in composite simulation models of implants. Titanium and zirconia models of implants were used as a reference for the evaluation of the intensity of artefacts. Methods: Seven different percentages of radio-opacifying BaAlSiO2 fillers were added to composite resin to fabricate seven step wedges and simulation models of implants. Titanium and zirconia simulation models of implants were also fabricated. Aluminium step wedge was used as a reference for the measurement of grey values in intraoral radiographs. Step wedges were exposed with a Planmeca Intra X-ray machine (Planmeca Oy, Helsinki, Finland). All composite, titanium and zirconia simulation models of implants were exposed with a SCANORA® 3D dental X-ray machine (Soredex, Tuusula, Finland). Images and grey values were analysed with ImageJ software (National Institutes of Health, Bethesda, MD). To demonstrate possible artefacts between all the simulation models of implants, the images were also visually compared with each other using ImageJ software. Results: Artefacts were clearly present in CBCT images caused by titanium and zirconia and when the composite material consisted at least 20% BaAlSiO2. The intensity of artefacts increased when the radio-opacity of the composite material increased. Conclusions: Materials containing less radio-opacity produce less pronounced artefacts. The cut-off point for artefacts is at 20% radio-opaque filling material in composite material. PMID:25283364
Optimisation Of Cutting Parameters Of Composite Material Laser Cutting Process By Taguchi Method
NASA Astrophysics Data System (ADS)
Lokesh, S.; Niresh, J.; Neelakrishnan, S.; Rahul, S. P. Deepak
2018-03-01
The aim of this work is to develop a laser cutting process model that can predict the relationship between the process input parameters and resultant surface roughness, kerf width characteristics. The research conduct is based on the Design of Experiment (DOE) analysis. Response Surface Methodology (RSM) is used in this work. It is one of the most practical and most effective techniques to develop a process model. Even though RSM has been used for the optimization of the laser process, this research investigates laser cutting of materials like Composite wood (veneer)to be best circumstances of laser cutting using RSM process. The input parameters evaluated are focal length, power supply and cutting speed, the output responses being kerf width, surface roughness, temperature. To efficiently optimize and customize the kerf width and surface roughness characteristics, a machine laser cutting process model using Taguchi L9 orthogonal methodology was proposed.
NASA Astrophysics Data System (ADS)
Cevizci, Halim
2014-10-01
In this study, the plaster stemming application for blasting at a basalt quarry is studied. Drill cuttings are generally used in open pits and quarries as the most common stemming material since these are most readily available at blast sites. However, dry drill cuttings eject very easily from blastholes without offering much resistance to blast energy. The plaster stemming method has been found to be better than the drill cuttings stemming method due to increased confinement inside the hole and better utilization of blast explosive energy in the rock. The main advantage of the new stemming method is the reduction in the cost of blasting. At a basalt quarry, blasting costs per unit volume of rock were reduced to 15% by increasing burden and spacing distances. In addition, better fragmentation was obtained by using the plaster stemming method. Blast trials showed that plaster stemming produced finer material. In the same blast tests, +30 cm size fragments were reduced to 47.3% of the total, compared to 32.6% in the conventional method of drill cuttings stemming. With this method of stemming, vibration and air shock values increased slightly due to more blast energy being available for rock breakage but generally these increased values were small and stayed under the permitted limit for blast damage criteria unless measuring distance is too close.
NASA Astrophysics Data System (ADS)
Konig, Karsten; Wang, Bagui; Krauss, Oliver; Riemann, Iris; Schubert, Harald; Kirste, Sigrun; Fischer, Peter
2004-07-01
We report on a method for refractive laser surgery based on low-energy femtosecond laser pulses provided by ultracompact turn-key non-amplified laser systems. An additional excimer laser is not required for ablation of the stroma. The novel method has the potential to be used for (i) optical flap creation as well as stroma ablation and (ii) for non-invasive flap-free intrastromal ablation. In addition, 3D multiphoton imaging of the cornea can be performed. In particular, we used sub-nanojoule near infrared 80 MHz femtosecond laser pulses for multiphoton imaging of corneal structures with ultrahigh resolution (< 1μm) as well as for highly precise intraocular refractive surgery. Imaging based on two-photon excited cellular autofluorescence and SHG formation in collagen structures was performed at GW/cm2 intensities, whereas destructive optical breakdown for nanoprocessing occurred at TW/cm2 light intensities. These high intensities were realized with sub-nJ pulses within a subfemtoliter intrastromal volume by diffraction-limited focussing with high NA objectives and beam scanning 50 to 140 μm below the epithelial surface. Multiphoton tomography of the cornea was used to determine the target of interest and to visualize intraocular post-laser effects. Histological examination with light- and electron microscopes of laser-exposed porcine and rabbit eyes reveal a minimum intratissue cut size below 1 μm without destructive effects to surrounding collagen structures. LASIK flaps and intracorneal cavities could be realized with high precision using 200 fs, 80 MHz, sub-nanojoule pulses at 800 nm. First studies on 80 MHz femtosecond laser surgery on living rabbits have been performed.
Digital modeling of end-mill cutting tools for FEM applications from the active cutting contour
NASA Astrophysics Data System (ADS)
Salguero, Jorge; Marcos, M.; Batista, M.; Gómez, A.; Mayuet, P.; Bienvenido, R.
2012-04-01
A very current technique in the research field of machining by material removal is the use of simulations using the Finite Element Method (FEM). Nevertheless, and although is widely used in processes that allows approximations to orthogonal cutting, such as shaping, is scarcely used in more complexes processes, such as milling. This fact is due principally to the complex geometry of the cutting tools in these processes, and the need to realize the studi es in an oblique cutting configuration. This paper shows a methodology for the geometrical characterization of commercial endmill cutting tools, by the extraction of the cutting tool contour, making use of optical metrology, and using this geometry to model the active cutting zone with a 3D CAD software. This model is easily exportable to different CAD formats, such as IGES or STEP, and importable from FEM software, where is possible to study the behavior in service of the same ones.
Khode, Rajiv Tarachand; Shenoi, Pratima Ramakrishna; Kubde, Rajesh R.; Makade, Chetana S.; Wadekar, Kanchan D.; Khode, Priyanka Tarachand
2017-01-01
Aims: This study evaluated effect of infection control barriers on light intensity (LI) of light-curing unit (LCU) and microhardness of composite. Materials and Methods: Four different disposable barriers (n = 30) were tested against the control. LI for each barrier was measured with Lux meter. One hundred and fifty Teflon molds were equally divided into five groups of thirty each. Composite was filled in bulk in these molds and cured without and with barrier. Microhardness was evaluated on top and bottom surface of composite specimen with microhardness testing machine and hardness ratio (HR) was derived. Statistical Analysis Used: One-way analysis of variance, Tukey's honestly significant difference test, and paired t-test using SPSS version 18 software. Results: All barriers had significantly reduced the baseline LI of LCU (P < 0.0001), but only Cure Elastic Steri-Shield and latex cut glove pieces (LCGP) significantly reduced the microhardness of the composite (P < 0.05). However, HR determined inadequate curing only with LCGP. Conclusions: Although entire tested barrier significantly reduced the LI; none, except LCGP markedly affected the degree of cure of the composite. PMID:29279622
Shaping Cutter Original Profile for Fine-module Ratchet Teeth Cutting
NASA Astrophysics Data System (ADS)
Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.
2018-03-01
The methods for determining geometric characteristics of a theoretical original profile of the cutter for cutting ratchet teeth with a module of 0.3–1.0 mm are considered in the article. Design models describing the shaping process of cutting edges of cutter teeth are developed. Systems of expressions for determining coordinates of the points of front and back edges of cutter teeth; the workpiece angles of rotation during the cutting process; the minimum cutter radius are received. The basic data when using the proposed technique are: radii of circumferences passing through cavities of cutter teeth and external cut teeth; the gradient angle and length of straight section of the front edge of a cut tooth; angles of rotation of the cutter and the workpiece at the moment of shaping.
NASA Astrophysics Data System (ADS)
Zainal Ariffin, S.; Razlan, A.; Ali, M. Mohd; Efendee, A. M.; Rahman, M. M.
2018-03-01
Background/Objectives: The paper discusses about the optimum cutting parameters with coolant techniques condition (1.0 mm nozzle orifice, wet and dry) to optimize surface roughness, temperature and tool wear in the machining process based on the selected setting parameters. The selected cutting parameters for this study were the cutting speed, feed rate, depth of cut and coolant techniques condition. Methods/Statistical Analysis Experiments were conducted and investigated based on Design of Experiment (DOE) with Response Surface Method. The research of the aggressive machining process on aluminum alloy (A319) for automotive applications is an effort to understand the machining concept, which widely used in a variety of manufacturing industries especially in the automotive industry. Findings: The results show that the dominant failure mode is the surface roughness, temperature and tool wear when using 1.0 mm nozzle orifice, increases during machining and also can be alternative minimize built up edge of the A319. The exploration for surface roughness, productivity and the optimization of cutting speed in the technical and commercial aspects of the manufacturing processes of A319 are discussed in automotive components industries for further work Applications/Improvements: The research result also beneficial in minimizing the costs incurred and improving productivity of manufacturing firms. According to the mathematical model and equations, generated by CCD based RSM, experiments were performed and cutting coolant condition technique using size nozzle can reduces tool wear, surface roughness and temperature was obtained. Results have been analyzed and optimization has been carried out for selecting cutting parameters, shows that the effectiveness and efficiency of the system can be identified and helps to solve potential problems.
Determination of glucose-6-phosphate dehydrogenase cut-off values in a Tunisian population.
Laouini, Naouel; Sahli, Chaima Abdelhafidh; Jouini, Latifa; Haloui, Sabrine; Fredj, Sondes Hadj; Daboubi, Rym; Siala, Hajer; Ouali, Faida; Becher, Meriam; Toumi, Nourelhouda; Bibi, Amina; Messsaoud, Taieb
2017-07-26
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest enzymopathy worldwide. The incidence depends essentially on the methods used for the assessment. In this respect, we attempted in this study to set cut-off values of G6PD activity to discriminate among normal, heterozygous, and deficient individuals using the World Health Organization (WHO) classification and the receiver operating characteristics (ROC) curve analysis. Blood samples from 250 female and 302 male subjects were enrolled in this study. The G6PD activity was determined using a quantitative assay. The common G6PD mutations in Tunisia were determined using the amplification refractory mutation system (ARMS-PCR) method. The ROC curve was used to choice the best cut-off. Normal G6PD values were 7.69±2.37, 7.86±2.39, and 7.51±2.35 U/g Hb for the entire, male, and female groups, respectively. Cut-off values for the total, male, and female were determined using the WHO classification and ROC curves analysis. In the male population, both cut-offs established using ROC curve analysis (4.00 U/g Hb) and the 60% level (3.82 U/g Hb), respectively are sensitive and specific resulting in a good efficiency of discrimination between deficient and normal males. For the female group the ROC cut-off (5.84 U/g Hb) seems better than the 60% level cut-off (3.88 U/g Hb) to discriminate between normal and heterozygote or homozygote women with higher Youden Index. The establishment of the normal values for a population is important for a better evaluation of the assay result. The ROC curve analysis is an alternative method to determine the status of patients since it correlates DNA analysis and G6PD activity.
Wei, Yingying; An, Qinglong; Cai, Xiaojiang; Chen, Ming; Ming, Weiwei
2015-10-02
The purpose of this article is to investigate the influences of carbon fibers on the fracture mechanism of carbon fibers both in macroscopic view and microscopic view by using single-point flying cutting method. Cutting tools with three different materials were used in this research, namely, PCD (polycrystalline diamond) tool, CVD (chemical vapor deposition) diamond thin film coated carbide tool and uncoated carbide tool. The influence of fiber orientation on the cutting force and fracture topography were analyzed and conclusions were drawn that cutting forces are not affected by cutting speeds but significantly influenced by the fiber orientation. Cutting forces presented smaller values in the fiber orientation of 0/180° and 15/165° but the highest one in 30/150°. The fracture mechanism of carbon fibers was studied in different cutting conditions such as 0° orientation angle, 90° orientation angle, orientation angles along fiber direction, and orientation angles inverse to the fiber direction. In addition, a prediction model on the cutting defects of carbon fiber reinforced plastic was established based on acoustic emission (AE) signals.
Wei, Yingying; An, Qinglong; Cai, Xiaojiang; Chen, Ming; Ming, Weiwei
2015-01-01
The purpose of this article is to investigate the influences of carbon fibers on the fracture mechanism of carbon fibers both in macroscopic view and microscopic view by using single-point flying cutting method. Cutting tools with three different materials were used in this research, namely, PCD (polycrystalline diamond) tool, CVD (chemical vapor deposition) diamond thin film coated carbide tool and uncoated carbide tool. The influence of fiber orientation on the cutting force and fracture topography were analyzed and conclusions were drawn that cutting forces are not affected by cutting speeds but significantly influenced by the fiber orientation. Cutting forces presented smaller values in the fiber orientation of 0/180° and 15/165° but the highest one in 30/150°. The fracture mechanism of carbon fibers was studied in different cutting conditions such as 0° orientation angle, 90° orientation angle, orientation angles along fiber direction, and orientation angles inverse to the fiber direction. In addition, a prediction model on the cutting defects of carbon fiber reinforced plastic was established based on acoustic emission (AE) signals. PMID:28793597
MIRAP, microcomputer reliability analysis program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jehee, J.N.T.
1989-01-01
A program for a microcomputer is outlined that can determine minimal cut sets from a specified fault tree logic. The speed and memory limitations of the microcomputers on which the program is implemented (Atari ST and IBM) are addressed by reducing the fault tree's size and by storing the cut set data on disk. Extensive well proven fault tree restructuring techniques, such as the identification of sibling events and of independent gate events, reduces the fault tree's size but does not alter its logic. New methods are used for the Boolean reduction of the fault tree logic. Special criteria formore » combining events in the 'AND' and 'OR' logic avoid the creation of many subsuming cut sets which all would cancel out due to existing cut sets. Figures and tables illustrates these methods. 4 refs., 5 tabs.« less
IndeCut evaluates performance of network motif discovery algorithms.
Ansariola, Mitra; Megraw, Molly; Koslicki, David
2018-05-01
Genomic networks represent a complex map of molecular interactions which are descriptive of the biological processes occurring in living cells. Identifying the small over-represented circuitry patterns in these networks helps generate hypotheses about the functional basis of such complex processes. Network motif discovery is a systematic way of achieving this goal. However, a reliable network motif discovery outcome requires generating random background networks which are the result of a uniform and independent graph sampling method. To date, there has been no method to numerically evaluate whether any network motif discovery algorithm performs as intended on realistically sized datasets-thus it was not possible to assess the validity of resulting network motifs. In this work, we present IndeCut, the first method to date that characterizes network motif finding algorithm performance in terms of uniform sampling on realistically sized networks. We demonstrate that it is critical to use IndeCut prior to running any network motif finder for two reasons. First, IndeCut indicates the number of samples needed for a tool to produce an outcome that is both reproducible and accurate. Second, IndeCut allows users to choose the tool that generates samples in the most independent fashion for their network of interest among many available options. The open source software package is available at https://github.com/megrawlab/IndeCut. megrawm@science.oregonstate.edu or david.koslicki@math.oregonstate.edu. Supplementary data are available at Bioinformatics online.
Tension Behaviour on the Connection of the Cold-Formed Cut-Curved Steel Channel Section
NASA Astrophysics Data System (ADS)
Sani, Mohd Syahrul Hisyam Mohd; Muftah, Fadhluhartini; Fakri Muda, Mohd; Siang Tan, Cher
2017-08-01
Cold-formed steel (CFS) are utilised as a non-structural and structural element in construction activity especially a residential house and small building roof truss system. CFS with a lot of advantages and some of disadvantages such as buckling that must be prevented for roof truss production are being studied equally. CFS was used as a top chord of the roof truss system which normally a slender section is dramatically influenced to buckling failure and instability of the structure. So, the curved section is produced for a top chord for solving the compression member of the roof truss. Besides, there are lacked of design and production information about the CFS curved channel section. In the study, the CFS is bent by using a cut-curved method because of ease of production, without the use of skilled labour and high cost machine. The tension behaviour of the strengthening method of cut-curved or could be recognised as a connection of the cut-curved section was tested and analysed. There are seven types of connection was selected. From the testing and observation, it is shown the specimen with full weld along the cut section and adds with flange element plate with two self-drilling screws (F7A) was noted to have a higher value of ultimate load. Finally, there are three alternative methods of connection for CFS cut-curved that could be a reference for a contractor and further design.
Computational Efficiency of the Simplex Embedding Method in Convex Nondifferentiable Optimization
NASA Astrophysics Data System (ADS)
Kolosnitsyn, A. V.
2018-02-01
The simplex embedding method for solving convex nondifferentiable optimization problems is considered. A description of modifications of this method based on a shift of the cutting plane intended for cutting off the maximum number of simplex vertices is given. These modification speed up the problem solution. A numerical comparison of the efficiency of the proposed modifications based on the numerical solution of benchmark convex nondifferentiable optimization problems is presented.
The ongoing violence against women: Female Genital Mutilation/Cutting.
Muteshi, Jacinta K; Miller, Suellen; Belizán, José M
2016-04-18
Female Genital Mutilation/Cutting (FGM/C) comprises different practices involving cutting, pricking, removing and sometimes sewing up external female genitalia for non-medical reasons. The practice of FGM/C is highly concentrated in a band of African countries from the Atlantic coast to the Horn of Africa, in areas of the Middle East such as Iraq and Yemen, and in some countries in Asia like Indonesia. Girls exposed to FGM/C are at risk of immediate physical consequences such as severe pain, bleeding, and shock, difficulty in passing urine and faeces, and sepsis. Long-term consequences can include chronic pain and infections. FGM/C is a deeply entrenched social norm, perpetrated by families for a variety of reasons, but the results are harmful. FGM/C is a human rights issue that affects girls and women worldwide. The practice is decreasing, due to intensive advocacy activities of international, national, and grassroots agencies. An adolescent girl today is about a third less likely to be cut than 30 years ago. However, the rates of abandonment are not high enough, and change is not happening as rapidly as necessary. Multiple interventions have been implemented, but the evidence base on what works is lacking. We in reproductive health must work harder to find strategies to help communities and families abandon these harmful practices.
Factors affecting microcuttings of Stevia using a mist-chamber propagation box.
Osman, Mohamad; Samsudin, Nur Syamimi; Faruq, Golam; Nezhadahmadi, Arash
2013-01-01
Stevia rebaudiana Bertoni is a member of Compositae family. Stevia plant has zero calorie content and its leaves are estimated to be 300 times sweeter than sugar. This plant is believed to be the most ideal substitute for sugar and important to assist in medicinal value especially for diabetic patients. In this study, microcutting techniques using a mist-chamber propagation box were used as it was beneficial for propagation of Stevia and gave genetic uniformity to the plant. The effects of different treatments on root stimulation of Stevia in microcuttings technique were evaluated. Treatments studied were different sizes of shoot cuttings, plant growth regulators, lights, and shades. Data logger was used to record the mean value of humidity (>90% RH), light intensity (673-2045 lx), and temperature (28.6-30.1°C) inside the mist-chamber propagation box. From analysis of variance, there were significant differences between varieties and treatments in parameters studied (P < 0.05). For the size of shoot cuttings treatment, 6 nodes cuttings were observed to increase root number. As compared to control, shoot cuttings treated with indole butyric acid (IBA) had better performance regarding root length. Yellow light and 50% shade treatments showed higher root and leaf number and these conditions can be considered as crucial for potential propagation of Stevia.
Diagnosis of edge condition based on force measurement during milling of composites
NASA Astrophysics Data System (ADS)
Felusiak, Agata; Twardowski, Paweł
2018-04-01
The present paper presents comparative results of the forecasting of a cutting tool wear with the application of different methods of diagnostic deduction based on the measurement of cutting force components. The research was carried out during the milling of the Duralcan F3S.10S aluminum-ceramic composite. Prediction of the toolwear was based on one variable, two variables regression Multilayer Perceptron(MLP)and Radial Basis Function(RBF)neural networks. Forecasting the condition of the cutting tool on the basis of cutting forces has yielded very satisfactory results.
Study on processing parameters of glass cutting by nanosecond 532 nm fiber laser
NASA Astrophysics Data System (ADS)
Wang, Jin; Gao, Fan; Xiong, Baoxing; Zhang, Xiang; Yuan, Xiao
2018-03-01
The processing parameters of soda-lime glass cutting with several nanosecond 532 nm pulsed fiber laser are studied in order to obtain sufficiently large ablation rate and better processing quality. The influences of laser processing parameters on effective cutting speed and cutting quality of 1 2 mm thick soda-lime glass are studied. The experimental results show that larger laser pulse energy will lead to higher effective cutting speed and larger maximum edge collapse of the front side of the glass samples. Compared with that of 1.1 mm thick glass samples, the 2.0 mm thick glass samples is more difficult to cut. With the pulse energy of 51.2 μJ, the maximum edge collapse is more than 200 μm for the 2.0 mm thick glass samples. In order to achieve the high effective cutting speed and good cutting quality at the same time, the dual energy overlapping method is used to obtain the better cutting performance for the 2.0 mm thick glass samples, and the cutting speed of 194 mm/s and the maximum edge collapse of less than 132 μm are realized.
Cutting Zone Temperature Identification During Machining of Nickel Alloy Inconel 718
NASA Astrophysics Data System (ADS)
Czán, Andrej; Daniš, Igor; Holubják, Jozef; Zaušková, Lucia; Czánová, Tatiana; Mikloš, Matej; Martikáň, Pavol
2017-12-01
Quality of machined surface is affected by quality of cutting process. There are many parameters, which influence on the quality of the cutting process. The cutting temperature is one of most important parameters that influence the tool life and the quality of machined surfaces. Its identification and determination is key objective in specialized machining processes such as dry machining of hard-to-machine materials. It is well known that maximum temperature is obtained in the tool rake face at the vicinity of the cutting edge. A moderate level of cutting edge temperature and a low thermal shock reduce the tool wear phenomena, and a low temperature gradient in the machined sublayer reduces the risk of high tensile residual stresses. The thermocouple method was used to measure the temperature directly in the cutting zone. An original thermocouple was specially developed for measuring of temperature in the cutting zone, surface and subsurface layers of machined surface. This paper deals with identification of temperature and temperature gradient during dry peripheral milling of Inconel 718. The measurements were used to identification the temperature gradients and to reconstruct the thermal distribution in cutting zone with various cutting conditions.
L. Finer; M. Jurgensen; M. Palviainen; S. Piirainen; Deborah Page-Dumroese
2016-01-01
Coarse woody debris (CWD) serves a variety of ecological functions in forests, and the understanding of its decomposition is needed for estimating changes in CWD-dependent forest biodiversity, and for the quantification of forest ecosystem carbon and nutrient pools and fluxes. Boreal forests are often intensively managed, so information is needed on the effects of...