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Sample records for cutting force signature

  1. Influence of vegetable based cutting fluids on cutting force and vibration signature during milling of aluminium metal matrix composites

    Directory of Open Access Journals (Sweden)

    S. Shankar

    2017-03-01

    Full Text Available Due to the environmental and health issues, there is an enormous requirement for developing the novel cutting fluids (CFs. The vegetable based cutting fluid (VBCFs doesn’t affect the environment, diminish the harmful effects to the operator and also enhance the machining performances such as surface roughness, tool life, minimum vibration and cutting forces. In this work, the performances of four different VBCFs like palm, coconut, sunflower, soya bean oils, and a commercial type of CFs were considered to analyze the influence of cutting fluids while measuring the cutting force and vibration signatures during milling of 7075–T6 hybrid aluminium metal matrix composite with carbide insert tool. The experiments were conducted in CNC L-MILL 55 vertical machining center, with milling tool dynamometer to measure the cutting force and a tri-axial accelerometer to measure the vibration signals. The flow rate of the VBCFs were maintained at a constant rate and the results were compared with a commercial cutting fluid. The obtained result shows that palm oil suits better than the other vegetable based cutting fluids in terms of minimum cutting force requirement and minimum vibration. Also, the experimental result shows that the cutting fluid was one of the important parameter needs to be considered which influences the cutting force and vibration signals.

  2. Cutting forces during turning with variable depth of cut

    Directory of Open Access Journals (Sweden)

    M. Sadílek

    2016-03-01

    The proposed research for the paper is an experimental work – measuring cutting forces and monitoring of the tool wear on the cutting edge. It compares the turning where standard roughing cycle is used and the turning where the proposed roughing cycle with variable depth of cut is applied.

  3. A cutting force model for micromilling applications

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2006-01-01

    In micro milling the maximum uncut chip thickness is often smaller than the cutting edge radius. This paper introduces a new cutting force model for ball nose micro milling that is capable of taking into account the effect of the edge radius.......In micro milling the maximum uncut chip thickness is often smaller than the cutting edge radius. This paper introduces a new cutting force model for ball nose micro milling that is capable of taking into account the effect of the edge radius....

  4. Analysis of changes in paper cutting forces during the cutting cycle in single-knife guillotine

    OpenAIRE

    Rusin, Agnieszka; Petriaszwili, Georgij

    2013-01-01

    Paper presents the results of changes in the three components of cutting forces of paper stacks cutting during the cutting cycle in single-knife guillotine. The changes of the three components of cutting force at different stages of cutting cycle were analyzed.

  5. An Experimental Study of the Cutting Forces in Metal Turning

    Directory of Open Access Journals (Sweden)

    Zoltan Iosif Korka

    2013-09-01

    Full Text Available Cutting forces are classified among the most important technological parameters in machining process. Cutting forces are the background for the evaluation of the necessary machining power, as well as for dimensioning of the tools. Cutting forces are also having a major influence on the deformation of the work piece machined, its dimensional accuracy, and machining system stability.

  6. Research on the Effect of Cutting Parameters on Chip Formation and Cutting Force in Elliptical Vibration Cutting Process

    Science.gov (United States)

    Lin, Jieqiong; Guan, Liang; Lu, Mingming; Han, Jinguo; Feng, Da

    2017-12-01

    Elliptical vibration cutting (EVC) has been widely concerned since it was proposed, and its unique characteristics such as friction reversal and intermittent cutting can effectively extend the tool life, improve the machined surface roughness and so on. The objective of this paper was to predict the behavior of cutting force. A method of predicting the behavior of cutting force based on the chip thickness under various cutting conditions is proposed. Based on the established tool motion model, the chip model was founded. By numerical simulation, the effects of cutting parameters on cutting force under various cutting conditions were studied. The results show that the chip thickness can be used to predict the behavior of cutting force.

  7. Effect of Type of Cutting Tips on Cutting Forces in Turning

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    Polák Pavel

    2014-10-01

    Full Text Available The aim of this article is to demonstrate the efect of cutting materials and geometry of cutting tips on cutting forces in turning as well as the quality and precision of machined surface. The experiment focuses on measuring cutting forces when turning a sample of steel 11 523 at a constant feed rate and cut depth and at varying speeds of a spindle. Measurements were made using exchangeable cutting tips of diferent types. The results will be evaluated in terms of the impact of diferent characteristics of cutting tips and variable spindle speeds.

  8. Modeling and analysis of the chip formation and transient cutting force during elliptical vibration cutting process

    Science.gov (United States)

    Lin, Jieqiong; Guan, Liang; Lu, Mingming; Han, Jinguo; Kan, Yudi

    2017-12-01

    In traditional diamond cutting, the cutting force is usually large and it will affect tool life and machining quality. Elliptical vibration cutting (EVC) as one of the ultra-precision machining technologies has a lot of advantages, such as reduces cutting force, extend tool life and so on. It's difficult to predict the transient cutting force of EVC due to its unique elliptical motion trajectory. Study on chip formation will helpfully to predict cutting force. The geometric feature of chip has important effects on cutting force, however, few scholars have studied the chip formation. In order to investigate the time-varying cutting force of EVC, the geometric feature model of chip is established based on analysis of chip formation, and the effects of cutting parameters on the geometric feature of chip are analyzed. To predict transient force quickly and effectively, the geometric feature of chip is introduced into the cutting force model. The calculated results show that the error between the predicted cutting force in this paper and that in the literature is less than 2%, which proves its feasibility.

  9. Modeling and analysis of the chip formation and transient cutting force during elliptical vibration cutting process

    Directory of Open Access Journals (Sweden)

    Jieqiong Lin

    2017-12-01

    Full Text Available In traditional diamond cutting, the cutting force is usually large and it will affect tool life and machining quality. Elliptical vibration cutting (EVC as one of the ultra-precision machining technologies has a lot of advantages, such as reduces cutting force, extend tool life and so on. It’s difficult to predict the transient cutting force of EVC due to its unique elliptical motion trajectory. Study on chip formation will helpfully to predict cutting force. The geometric feature of chip has important effects on cutting force, however, few scholars have studied the chip formation. In order to investigate the time-varying cutting force of EVC, the geometric feature model of chip is established based on analysis of chip formation, and the effects of cutting parameters on the geometric feature of chip are analyzed. To predict transient force quickly and effectively, the geometric feature of chip is introduced into the cutting force model. The calculated results show that the error between the predicted cutting force in this paper and that in the literature is less than 2%, which proves its feasibility.

  10. Monitoring machining conditions by analyzing cutting force vibration

    International Nuclear Information System (INIS)

    Piao, Chun Guang; Kim, Ju Wan; Kim, Jin Oh; Shin, Yoan

    2015-01-01

    This paper deals with an experimental technique for monitoring machining conditions by analyzing cutting-force vibration measured at a milling machine. This technique is based on the relationship of the cutting-force vibrations with the feed rate and cutting depth as reported earlier. The measurement system consists of dynamic force transducers and a signal amplifier. The analysis system includes an oscilloscope and a computer with a LabVIEW program. Experiments were carried out at various feed rates and cutting depths, while the rotating speed was kept constant. The magnitude of the cutting force vibration component corresponding to the number of cutting edges multiplied by the frequency of rotation was linearly correlated with the machining conditions. When one condition of machining is known, another condition can be identified by analyzing the cutting-force vibration

  11. Cutting Forces Prediction in the Dry Slotting of Aluminium Stacks

    OpenAIRE

    SALGUERO, Jorge; CALAMAZ, Madalina; BATISTA, Moises; GIROT, Franck; MARCOS, Mariano

    2014-01-01

    International audience; Cutting forces are one of the inherent phenomena and a very significant indicator of themetal cutting process. The work presented in this paper is an investigation of the prediction of these parameters in slotting processes of UNS A92024-T3 (Al-Cu) stacks. So, cutting speed (V) and feed per tooth (fz) based parametric models, for experimental components of cutting force, F(fz,V) have been proposed. These models have been developed from the individual models extracted f...

  12. ANALYSIS OF CUTTING FORCES ON CNC LATHES EXPERIMENTAL APPROACH

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    Erdem Koç

    1996-01-01

    Full Text Available Objective of this study is to make use easy programming of CNC lathes and to achieve the optimization of part program prepared considering the limiting parameters of the machine. In the present study, a BOXFORD 250 B CNC lathe has been used for experiment and optimization process. The measurement of cutting forces exerted on the cutting tool of CNC lathe has been performed. The cutting forces occurring during the turning operation have been determined for different depth of" cut, feed rate and cutting speed as well as different cutting tools and related data base has been obtained.

  13. Cutting force simulation in milling with multi-edges cutter

    Science.gov (United States)

    Tamura, Shoichi; Matsumura, Takashi

    2017-10-01

    In the aircraft parts, the portion of titanium alloy, one of the light-weight and high mechanical strength materials, has been increased in terms of the fuel efficiency. Therefore, the effective technologies in cutting of titanium alloy should be established to promote the material removal rate with high production quality. Multi-edges milling cutters, on which many inserts are helically aligned, have been commercially available for millings of deep sinking in large axial depth of cuts. The paper presents an analytical prediction model to control the cutting force with alignment and geometry of the insert. In the model, three dimensional chip flow on each insert is interpreted as a piling up of the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities, where the chip flow direction is determined to minimize the cutting energy. Then, the cutting force is predicted in the determined chip flow model. The cutting tests were conducted to validate the force model.

  14. The Cutting Process, Chips and Cutting Forces in Machining CFRP

    DEFF Research Database (Denmark)

    Koplev, A.; Lystrup, Aage; Vorm, T.

    1983-01-01

    The cutting of unidirectional CFRP, perpendicular as well as parallel to the fibre orientation, is examined. Shaping experiments, ‘quick-stop’ experiments, and a new chip preparation technique are used for the investigation. The formation of the chips, and the quality of the machined surface...

  15. Force Modelling in Orthogonal Cutting Considering Flank Wear Effect

    Science.gov (United States)

    Rathod, Kanti Bhikhubhai; Lalwani, Devdas I.

    2017-05-01

    In the present work, an attempt has been made to provide a predictive cutting force model during orthogonal cutting by combining two different force models, that is, a force model for a perfectly sharp tool plus considering the effect of edge radius and a force model for a worn tool. The first force model is for a perfectly sharp tool that is based on Oxley's predictive machining theory for orthogonal cutting as the Oxley's model is for perfectly sharp tool, the effect of cutting edge radius (hone radius) is added and improve model is presented. The second force model is based on worn tool (flank wear) that was proposed by Waldorf. Further, the developed combined force model is also used to predict flank wear width using inverse approach. The performance of the developed combined total force model is compared with the previously published results for AISI 1045 and AISI 4142 materials and found reasonably good agreement.

  16. Investigations in high speed blanking: cutting forces and microscopic observations

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    Larue A.

    2010-06-01

    Full Text Available A new hopefull technique, called high speed blanking, has been investigated since few years. To understand the cutting process and how the tools have to be designed, this study is interrested in the cutting force measurement. A new cutting force measurement device has to be designed consider the industrial interest of such a study. The designed test bench induces a calibration process in order to stucy the cutting forces evolution. The paper is discussing the result that the peack load seems to decrease when the punch speed increases. Finally microscopic observations are made in order to find Adiabatic Shear Bands.

  17. Counterbalance of cutting force for advanced milling operations

    Science.gov (United States)

    Tsai, Nan-Chyuan; Shih, Li-Wen; Lee, Rong-Mao

    2010-05-01

    The goal of this work is to concurrently counterbalance the dynamic cutting force and regulate the spindle position deviation under various milling conditions by integrating active magnetic bearing (AMB) technique, fuzzy logic algorithm and an adaptive self-tuning feedback loop. Since the dynamics of milling system is highly determined by a few operation conditions, such as speed of spindle, cut depth and feedrate, therefore the dynamic model for cutting process is more appropriate to be constructed by experiments, instead of using theoretical approach. The experimental data, either for idle or cutting, are utilized to establish the database of milling dynamics so that the system parameters can be on-line estimated by employing the proposed fuzzy logic algorithm as the cutting mission is engaged. Based on the estimated milling system model and preset operation conditions, i.e., spindle speed, cut depth and feedrate, the current cutting force can be numerically estimated. Once the current cutting force can be real-time estimated, the corresponding compensation force can be exerted by the equipped AMB to counterbalance the cutting force, in addition to the spindle position regulation by feedback of spindle position. On the other hand, for the magnetic force is nonlinear with respect to the applied electric current and air gap, the characteristics of the employed AMB is investigated also by experiments and a nonlinear mathematic model, in terms of air gap between spindle and electromagnetic pole and coil current, is developed. At the end, the experimental simulations on realistic milling are presented to verify the efficacy of the fuzzy controller for spindle position regulation and the capability of the dynamic cutting force counterbalance.

  18. Application of Taguchi method for cutting force optimization in rock

    Indian Academy of Sciences (India)

    In this paper, an optimization study was carried out for the cutting force (Fc) acting on circular diamond sawblades in rock sawing. The peripheral speed, traverse speed, cut depth and flow rate of cooling fluid were considered as operating variables and optimized by using Taguchi approach for the Fc. L16(44) orthogonal ...

  19. Application of Taguchi method for cutting force optimization in rock ...

    Indian Academy of Sciences (India)

    In this paper, an optimization study was carried out for the cutting force (Fc) acting on circular diamond sawblades in rock sawing. The peripheral speed, traverse speed, cut depth and flow rate of cooling fluid were considered as operating variables and optimized by using Taguchi approach for the Fc. L16(44) orthogonal ...

  20. Evaluation of cutting force uncertainty components in turning

    DEFF Research Database (Denmark)

    Axinte, Dragos Aurelian; Belluco, Walter; De Chiffre, Leonardo

    2000-01-01

    A procedure is proposed for the evaluation of those uncertainty components of a single cutting force measurement in turning that are related to the contributions of the dynamometer calibration and the cutting process itself. Based on an empirical model including errors form both sources, the unce...

  1. Drilling of metal matrix composites: cutting forces and chip formation

    International Nuclear Information System (INIS)

    Songmene, V.; Balout, B.; Masounave, J.

    2002-01-01

    Particulate metal matrix composites (MMCs) are known for their low weight and their high wear resistance, but also for the difficulties encountered during their machining. New aluminium MMCs containing with both soft lubricating graphite particles and hard particles (silicon carbide or alumina) with improved machinability were developed. This study investigates the drilling of these composites as compared to non-reinforced aluminium. The microstructure of chip, the cutting forces, the shear angles and the friction at tool-chip interface are used to compare the machinability of these composites. It was found that, during drilling of this new family of composites, the feed rate, and the nature of reinforcing particles govern the cutting forces. The mathematical models established by previous researchers for predicting the cutting forces when drilling metals were validated for these composites. The reinforcing particles within the composite help for chip segmentation, making the composite more brittle and easy to shear during the cutting process. (author)

  2. Measuring forces in liver cutting: new equipment and experimental results.

    Science.gov (United States)

    Chanthasopeephan, Teeranoot; Desai, Jaydev P; Lau, Alan C W

    2003-12-01

    We are interested in modeling the liver cutting process as accurately as possible by determining the mechanical properties experimentally and developing a predictive model that is self-consistent with the experimentally determined properties. In this paper, we present the newly developed hardware and software to characterize the mechanical response of pig liver during (ex vivo) cutting. We describe the custom-made cutting apparatus, the data acquisition system, and the characteristics of the cutting force versus displacement plot. The force-displacement behavior appears to reveal that the cutting process consists of a sequence of intermittent localized crack extension in the tissue on the macroscopic scale. The macroscopic cutting force-displacement curve shows repeating self-similar units of localized linear loading followed by sudden unloading. The sudden unloading coincides with observed onset of localized crack growth. This experimental data were used to determine the self-consistent local effective Young's modulus for the specimens, to be used in finite element models. Results from finite element analyses models reveal that the magnitude of the self-consistent local effective Young's modulus determined by plane-stress and plane-strain varies within close bounds. Finally, we have also observed that the local effective Young's modulus determined by plane stress and plane strain analysis decreases with increasing cutting speed.

  3. Development of lathe tool dynamometer and finding cutting forces using negative and positive rake angle cutting tool

    International Nuclear Information System (INIS)

    Zeb, M.A.; Irfan, M.A.

    2005-01-01

    Most output parameters in machining, such as cutting forces, temperatures, strains and the work-hardening of the chip material, are directly related to the chip formation process. The characteristics of machining processes can be well understood if the forces and strains during chip formation are known. In this research a lathe tool dynamometer was used to measure cutting forces involved in machining of Steel 1045 and Aluminum 2219 T62. High Speed Steel (HSS), cutting tools with positive and negative rake angles were used. It was observed that more cutting forces are experienced by the cutting tool with positive rake angle as compared to the forces experienced by the cutting tool with negative rake angle. For steel 1045 the cutting forces using positive rake angle cutting tool were much higher. This suggested that for harder materials using a negative rake angle is more suitable for cutting. (author)

  4. Effects of cutting conditions on forces and force coefficients in plunge milling operations

    Directory of Open Access Journals (Sweden)

    Francesco Rafanelli

    2015-06-01

    Full Text Available The modeling of milling forces is a crucial issue to understand milling processes. In the literature, many force models and experiments to identify force coefficients are found. The objective of this article is to develop a new approach, based on the traditional average force method, able to measure and compute the cutting coefficients for end mills used in plunging operations. This model has been used to evaluate the effect of the radial engagement on the cutting coefficients themselves, proposing a new strategy to update these values for different cutting parameters. This dependency of the cutting coefficient is particularly important for the determination of the stability lobe diagrams, used to predict the chatter conditions. In this article, the method to assess the cutting coefficients, the results of the experimental tests, and the effect of condition-dependent cutting coefficients on process stability are presented.

  5. The effects of cutting parameters on cutting forces and heat generation when drilling animal bone and biomechanical test materials.

    Science.gov (United States)

    Cseke, Akos; Heinemann, Robert

    2018-01-01

    The research presented in this paper investigated the effects of spindle speed and feed rate on the resultant cutting forces (thrust force and torque) and temperatures while drilling SawBones ® biomechanical test materials and cadaveric cortical bone (bovine and porcine femur) specimens. It also investigated cortical bone anisotropy on the cutting forces, when drilling in axial and radial directions. The cutting forces are only affected by the feed rate, whereas the cutting temperature in contrast is affected by both spindle speed and feed rate. The temperature distribution indicates friction as the primary heat source, which is caused by the rubbing of the tool margins and the already cut chips over the borehole wall. Cutting forces were considerably higher when drilling animal cortical bone, in comparison to cortical test material. Drilling direction, and therewith anisotropy, appears to have a negligible effect on the cutting forces. The results suggest that this can be attributed to the osteons being cut at an angle rather than in purely axial or radial direction, as a result of a twist drill's point angle. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. Investigation of the Effect of Cutting Tool Rake Angle on Feed Force

    OpenAIRE

    GÜNAY, Mustafa; ŞEKER, Ulvi

    2005-01-01

    This paper presents a study of investigation into cutting tool rake angle effect on feed force to have secondary important during machining. For this purpose, a dynamometer was designed and manufactured for experimental determination of the cutting forces and mounted to a CNC turning centre. With the help of two beam type load cells suitably located on the dynamometer, it became possible to sense the cutting tool deflections due to the cutting forces. AISI 1040 was used as the workpiece mater...

  7. Surface roughness and cutting force estimation in the CNC turning using artificial neural networks

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    Mohammad Ramezani

    2015-04-01

    Full Text Available Surface roughness and cutting forces are considered as important factors to determine machinability rate and the quality of product. A number of factors like cutting speed, feed rate, depth of cutting and tool noise radius influence the surface roughness and cutting forces in turning process. In this paper, an Artificial Neural Network (ANN model was used to forecast surface roughness and cutting forces with related inputs, including cutting speed, feed rate, depth of cut and tool noise radius. The machined surface roughness and cutting force parameters related to input parameters are the outputs of the ANN model. In this work, 24 samples of experimental data were used to train the network. Moreover, eight other experimental tests were implemented to test the network. The study concludes that ANN was a reliable and accurate method for predicting machining parameters in CNC turning operation.

  8. Effect of reinforcement on the cutting forces while machining metal matrix composites–An experimental approach

    Directory of Open Access Journals (Sweden)

    Ch. Shoba

    2015-12-01

    Full Text Available Hybrid metal matrix composites are of great interest for researchers in recent years, because of their attractive superior properties over traditional materials and single reinforced composites. The machinabilty of hybrid composites becomes vital for manufacturing industries. The need to study the influence of process parameters on the cutting forces in turning such hybrid composite under dry environment is essentially required. In the present study, the influence of machining parameters, e.g. cutting speed, feed and depth of cut on the cutting force components, namely feed force (Ff, cutting force (Fc, and radial force (Fd has been investigated. Investigations were performed on 0, 2, 4, 6 and 8 wt% Silicon carbide (SiC and rice husk ash (RHA reinforced composite specimens. A comparison was made between the reinforced and unreinforced composites. The results proved that all the cutting force components decrease with the increase in the weight percentage of the reinforcement: this was probably due to the dislocation densities generated from the thermal mismatch between the reinforcement and the matrix. Experimental evidence also showed that built-up edge (BUE is formed during machining of low percentage reinforced composites at high speed and high depth of cut. The formation of BUE was captured by SEM, therefore confirming the result. The decrease of cutting force components with lower cutting speed and higher feed and depth of cut was also highlighted. The related mechanisms are explained and presented.

  9. A combination method of the theory and experiment in determination of cutting force coefficients in ball-end mill processes

    Directory of Open Access Journals (Sweden)

    Yung-Chou Kao

    2015-10-01

    Full Text Available In this paper, the cutting force calculation of ball-end mill processing was modeled mathematically. All derivations of cutting forces were directly based on the tangential, radial, and axial cutting force components. In the developed mathematical model of cutting forces, the relationship of average cutting force and the feed per flute was characterized as a linear function. The cutting force coefficient model was formulated by a function of average cutting force and other parameters such as cutter geometry, cutting conditions, and so on. An experimental method was proposed based on the stable milling condition to estimate the cutting force coefficients for ball-end mill. This method could be applied for each pair of tool and workpiece. The developed cutting force model has been successfully verified experimentally with very promising results.

  10. Machining of bone: Analysis of cutting force and surface roughness by turning process.

    Science.gov (United States)

    Noordin, M Y; Jiawkok, N; Ndaruhadi, P Y M W; Kurniawan, D

    2015-11-01

    There are millions of orthopedic surgeries and dental implantation procedures performed every year globally. Most of them involve machining of bones and cartilage. However, theoretical and analytical study on bone machining is lagging behind its practice and implementation. This study views bone machining as a machining process with bovine bone as the workpiece material. Turning process which makes the basis of the actually used drilling process was experimented. The focus is on evaluating the effects of three machining parameters, that is, cutting speed, feed, and depth of cut, to machining responses, that is, cutting forces and surface roughness resulted by the turning process. Response surface methodology was used to quantify the relation between the machining parameters and the machining responses. The turning process was done at various cutting speeds (29-156 m/min), depths of cut (0.03 -0.37 mm), and feeds (0.023-0.11 mm/rev). Empirical models of the resulted cutting force and surface roughness as the functions of cutting speed, depth of cut, and feed were developed. Observation using the developed empirical models found that within the range of machining parameters evaluated, the most influential machining parameter to the cutting force is depth of cut, followed by feed and cutting speed. The lowest cutting force was obtained at the lowest cutting speed, lowest depth of cut, and highest feed setting. For surface roughness, feed is the most significant machining condition, followed by cutting speed, and with depth of cut showed no effect. The finest surface finish was obtained at the lowest cutting speed and feed setting. © IMechE 2015.

  11. Cutting Forces Parametric Model for the Dry High Speed Contour Milling of Aerospace Aluminium Alloys

    OpenAIRE

    SALGUERO , JORGE; BATISTA , MOISES; CALAMAZ , Madalia; GIROT , Franck; MARCOS , MARIANO

    2013-01-01

    International audience; Cutting forces is one of the most important outputs in material removal machining processes. Their values depend on a large number of parameters, such as the cutting tool material and geometry, the workpiece material or the cutting parameters, among others. In this paper, cutting forces behavior have been analyzed as a function of feedrate and cutting speed, for the high-speed peripheral milling of UNS A92024-T3 (Al-Cu) stacks. This alloy is widely used in the manufact...

  12. The influence of mechanical properties of workpiece material on the main cutting force in face milling

    Directory of Open Access Journals (Sweden)

    M. Sekulić

    2010-10-01

    Full Text Available The paper presents the research into cutting forces in face milling of three different materials: steel Č 4732 (EN42CrMo4, nodular cast iron NL500 (EN-GJS-500-7 and silumine AlSi10Mg (EN AC-AlSi10Mg. Obtained results show that hardness and tensile strength values of workpiece material have a significant influence on the main cutting force, and thereby on the cutting energy in machining.

  13. Modelling the cutting edge radius size effect for force prediction in micro milling

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; Jan, Slunsky

    2008-01-01

    This paper presents a theoretical model for cutting force prediction in micro milling, taking into account the cutting edge radius size effect, the tool run out and the deviation of the chip flow angle from the inclination angle. A parameterization according to the uncut chip thickness to cutting...... edge radius ratio is used for the parameters involved in the force calculation. The model was verified by means of cutting force measurements in micro milling. The results show good agreement between predicted and measured forces. It is also demonstrated that the use of the Stabler's rule...... is a reasonable approximation and that micro end mill run out is effectively compensated by the deflections induced by the cutting forces....

  14. Sawtooth forces in cutting tropical hardwoods native to South America

    Science.gov (United States)

    S. P. Loehnertz; I. V. Cooz

    As a result of design, operation, and maintenance, sawblades used in tropical sawmills can cause many problems. Improvements in these areas are needed to reduce the waste associated with sawing of tropical species that are regarded as difficult to cut. In this study, cutting experiments that simulated bandsawing of tropical hardwoods showed the effect of chip...

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

    Science.gov (United States)

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

    2013-05-01

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

  16. EXAMINATION OF THE CUTTING FORCES OF AISI 304 AUSTENITIC STAINLESS STEEL IN THE TURNING PROCESS WITH TITANIUM CARBIDE COATED CUTTING TOOLS

    Directory of Open Access Journals (Sweden)

    Özgür TEKASLAN

    2007-02-01

    Full Text Available In this study, cutting forces occurring in the machining process of AISI 304 austenitic stainless steel specimen using titanium coated cutting tools are investigated experimentally and the results are compared to theoretical calculations. In the experimental study, various cutting speeds, feed rates and cutting depths are considered. Cutting forces are measured by 3-dimensional Kistler dynamometer. In the theoretically study, cutting forces are determined by Kienzle formulation. Consequently, it is found that the calculation of cutting forces in the theoretical method doesn't yield the exact results because of various factors and there is a % 25 average differences in accordance with the experimental results. Hence it is evaluated that the experimental technique in the determination of cutting forces yields more accurate results.

  17. Analysing a Relationship Between Wheel Wear and Cutting Forces During Diamond Grinding

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    M. A. Shavva

    2014-01-01

    Full Text Available In diamond grinding cutting forces affect the quality of the machined surface. We can estimate a wear rate of the diamond wheel by the magnitude of the forces and promptly resort to the restoration of its cutting properties. To solve this problem it is necessary to define a relationship between grinding wheel wear and cutting forces. There was no this dependence found in the sources of literature.The forces acting on a single worn diamond grain are considered to find the relationship between wheel wear and cutting forces. The main forces acting on the diamond grain are such as a reaction force of machining material, a frictional force over a worn place of the grain, and a total pressure on the contact surface of the grain and machining material. According to calculation results, in grinding the cutting forces are proportional to the hardness of machining material, and depend on the grain wear, as well as on the process operation conditions.The paper presents a technique for calculating the number of cutting (active grains per unit surface of diamond wheel to determine a total cutting force in grinding. The number of cutting grains depends on the properties of diamond wheel and on the operation conditions of grinding process.During grinding a total cutting force is calculated through the single grain cutting force, the number of cutting grains per unit surface of the grinding wheel and the contact area between the wheel and the work piece. Theoretical calculation of the forces is based on the condition that protrusions of all cutting grains are identical and all grains have a maximum wear, i.e. maximum worn place of grain.Calculations based on proposed theoretical formulas are compared with the calculations from the empirical formulas given in the literature. Varying the operation conditions of grinding makes the comparison. Convergence of results in the range of 5-20% is regarded as acceptable.On the BMSTU base flat diamond grinding of tungsten

  18. In processing of a spheroidized medium carbon steel, modelling with regression analysis of cutting forces and surface roughness affected by cutting parameters

    Directory of Open Access Journals (Sweden)

    Hüdayim Başak

    2016-08-01

    Full Text Available In this study, different spheronization heat treatment applied on a mild carbon steel during the machining was created main cutting forces and surface roughness value, were modeled by using multiple linear regression analysis. Main cutting force and surface roughness value which are dependent variable are described respectively rate of 94.6% and 94.2% by independent variables. The ANOVA significance test were used to determine dependent and independent variables correlations. Also, processing parameters variations such as effects on the feed rate, depth of cut and cutting force changes effect on surface roughness and main cutting force general effects were plotted to discuss.

  19. Multiple Regression Prediction Model for Cutting Forces in Turning Carbon-Reinforced PEEK CF30

    Directory of Open Access Journals (Sweden)

    Francisco Mata

    2010-01-01

    Full Text Available Among the thermoplastic polymers available, the reinforced polyetheretherketone with 30% of carbon fibres (PEEK CF 30 demonstrates a particularly good combination of strength, rigidity, and hardness, which prove ideal for industrial applications. Considering these properties and potential areas of application, it is necessary to investigate the machining of PEEK CF30. In this study, response surface methodology was applied to predict the cutting forces in turning operations using TiN-coated cutting tools under dry conditions where the machining parameters are cutting speed ranges, feed rate, and depth of cut. For this study, the experiments have been conducted using full factorial design in the design of experiments (DOEs on CNC turning machine. Based on statistical analysis, multiple quadratic regression model for cutting forces was derived with satisfactory 2-squared correlation. This model proved to be highly preferment for predicting cutting forces.

  20. Methods and Research for Multi-Component Cutting Force Sensing Devices and Approaches in Machining.

    Science.gov (United States)

    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.

  1. Methods and Research for Multi-Component Cutting Force Sensing Devices and Approaches in Machining

    Directory of Open Access Journals (Sweden)

    Qiaokang Liang

    2016-11-01

    Full Text Available 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.

  2. A High Performance Sensor for Triaxial Cutting Force Measurement in Turning

    Directory of Open Access Journals (Sweden)

    You Zhao

    2015-04-01

    Full Text Available This paper presents a high performance triaxial cutting force sensor with excellent accuracy, favorable natural frequency and acceptable cross-interference for high speed turning process. Octagonal ring is selected as sensitive element of the designed sensor, which is drawn inspiration from ring theory. A novel structure of two mutual-perpendicular octagonal rings is proposed and three Wheatstone full bridge circuits are specially organized in order to obtain triaxial cutting force components and restrain cross-interference. Firstly, the newly developed sensor is tested in static calibration; test results indicate that the sensor possesses outstanding accuracy in the range of 0.38%–0.83%. Secondly, impacting modal tests are conducted to identify the natural frequencies of the sensor in triaxial directions (i.e., 1147 Hz, 1122 Hz and 2035 Hz, which implies that the devised sensor can be used for cutting force measurement in a high speed lathe when the spindle speed does not exceed 17,205 rev/min in continuous cutting condition. Finally, an application of the sensor in turning process is operated to show its performance for real-time cutting force measurement; the measured cutting forces demonstrate a good accordance with the variation of cutting parameters. Thus, the developed sensor possesses perfect properties and it gains great potential for real-time cutting force measurement in turning.

  3. Force Relations and Dynamics of Cutting Knife in a Vertical Disc Mobile Wood Chipper

    Directory of Open Access Journals (Sweden)

    Segun R. BELLO

    2011-06-01

    Full Text Available The force relations and dynamics of cutting knife in a vertical disc wood chipper were investigated. The tool geometry determined include: rake angle (20 deg C; Shear angle, (fi= 52.15 deg C; the mean frictional angle, (t = 5.71 deg C. The analysis and comparison of the cutting forces has shown that the chips separated from the wood are being formed by off cutting, since normal applied force N is compressive in nature, the magnitude of the forces used by the knife on the wood is expected to increase as the cutting edge of the knife goes deeper into the wood until the value of the resisting force acting against the cut wood Ff is reached and exceeded. The evaluated forces acting on the knife and the chip are: F = 3.63Nmm^-1; N = 34.7 Nmm^-1; Fs= 27.45Nmm^-1; Fn =31.92 Nmm^-1; Ft = -8.46Nmm^-1; Fc = 33.85Nmm^-1. The resultant force acting on the tool face, Pr = 34.89Nmm^-1. The specific cutting pressure, Pc and cutting force needed to cut the timber, Fc, are 1.79 × 10^6 N/m2 and 644.84N respectively. The energy consumed in removing a unit volume of material is 69.96kJ/mm^-3 and the maximum power developed in cutting the chip is 3591.77W (4.82hp. The chipper efficiency (86.6% was evaluated by the highest percentage of accepted chip sizes.

  4. Rotary ultrasonic machining of CFRP: a mechanistic predictive model for cutting force.

    Science.gov (United States)

    Cong, W L; Pei, Z J; Sun, X; Zhang, C L

    2014-02-01

    Cutting force is one of the most important output variables in rotary ultrasonic machining (RUM) of carbon fiber reinforced plastic (CFRP) composites. Many experimental investigations on cutting force in RUM of CFRP have been reported. However, in the literature, there are no cutting force models for RUM of CFRP. This paper develops a mechanistic predictive model for cutting force in RUM of CFRP. The material removal mechanism of CFRP in RUM has been analyzed first. The model is based on the assumption that brittle fracture is the dominant mode of material removal. CFRP micromechanical analysis has been conducted to represent CFRP as an equivalent homogeneous material to obtain the mechanical properties of CFRP from its components. Based on this model, relationships between input variables (including ultrasonic vibration amplitude, tool rotation speed, feedrate, abrasive size, and abrasive concentration) and cutting force can be predicted. The relationships between input variables and important intermediate variables (indentation depth, effective contact time, and maximum impact force of single abrasive grain) have been investigated to explain predicted trends of cutting force. Experiments are conducted to verify the model, and experimental results agree well with predicted trends from this model. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Development and testing of an integrated smart tool holder for four-component cutting force measurement

    Science.gov (United States)

    Xie, Zhengyou; Lu, Yong; Li, Jianguang

    2017-09-01

    Cutting force measurement is a significant requirement for monitoring and controlling the machining processes. Hence, various methods of measuring the cutting force have been proposed by many researchers. In this study, an innovative integrated smart tool holder system based on capacitive sensors is designed, constructed and tested, which is capable of measuring triaxial cutting force and a torque simultaneously in a wireless environment system. A standard commercial tool holder is modified to make itself be the force sensing element that has advantages of simple structure and easy machining. Deformable beams are created in the tool holder, and the tiny deformations of which used to calculate the four-component cutting force are detected by six high precision capacitive sensors. All the sensors and other electronics, like data acquisition and transmitting unit, and wireless power unit, are incorporated into the tool holder as a whole system. The device is intended to be used in a rotating spindle such as in milling and drilling processes. Eventually, the static and dynamic characteristics of the smart tool holder have been determined by a series of tests. Cutting tests have also been carried out and the results show it is stable and practical to measure the cutting force in milling and drilling processes.

  6. Machinability evaluation of titanium alloys (Part 2)--Analyses of cutting force and spindle motor current.

    Science.gov (United States)

    Kikuchi, Masafumi; Okuno, Osamu

    2004-12-01

    To establish a method of determining the machinability of dental materials for CAD/CAM systems, the machinability of titanium, two titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb), and free-cutting brass was evaluated through cutting force and spindle motor current. The metals were slotted using a milling machine and square end mills at four cutting conditions. Both the static and dynamic components of the cutting force represented well the machinability of the metals tested: the machinability of Ti-6Al-4V and Ti-6Al-7Nb was worse than that of titanium, while that of free-cutting brass was better. On the other hand, the results indicated that the spindle motor current was not sensitive enough to detect the material difference among the titanium and its alloys.

  7. Laboratory versus industrial cutting force sensor in tool condition monitoring system

    International Nuclear Information System (INIS)

    Szwajka, K

    2005-01-01

    Research works concerning the utilisation of cutting force measures in tool condition monitoring usually present results and deliberations based on laboratory sensors. These sensors are too fragile to be used in industrial practice. Industrial sensors employed on the factory floor are less accurate, and this must be taken into account when creating a tool condition monitoring strategy. Another drawback of most of these works is that constant cutting parameters are used for the entire tool life. This does not reflect industrial practice where the same tool is used at different feeds and depths of cut in sequential passes. This paper presents a comparison of signals originating from laboratory and industrial cutting force sensors. The usability of the sensor output was studied during a laboratory simulation of industrial cutting conditions. Instead of building mathematical models for the correlation between tool wear and cutting force, an FFBP artificial neural network was used to find which combination of input data would provide an acceptable estimation of tool wear. The results obtained proved that cross talk between channels has an important influence on cutting force measurements, however this input configuration can be used for a tool condition monitoring system

  8. A Modernized UDM-600 Dynamometer-Based Setup for the Cutting Force Measurement

    Directory of Open Access Journals (Sweden)

    Ya. I. Shuliak

    2016-01-01

    Full Text Available The article considers development of a modernized UDM-600 dynamometer-based setup for measuring the cutting force components. Modernization of existing equipment to improve the method of recording the cutting force components in the automated mode is of relevance. The measuring setup allows recording the cutting force components in turning and milling, as well as the axial force and the torque in the drilling and milling operations.The article presents a block diagram and a schematic diagram of the setup to measure the cutting force components, and describes a basic principle of measuring units within the modernized setup. The developed setup uses a half-bridge strain gauge measuring circuit to record the cutting forces. To enhance the measuring circuit output voltage is used a 16-channel amplifier of LA-UN16 model with a discretely adjustable gain. To record and process electrical signals is used a data acquisition device of NI USB-6009 model, which enables transmitting the received data to a PC via USB-interface. The data acquisition device has a built-in stabilized DC power supply that is used to power the strain gauge bridges. A developed schematic diagram of the measuring setup allows us to realize this measuring device and implement its modernization.Final processing of recorded data is provided through the software developed in visual programming environment LabVIEW 9.0. The program allows us to show the real-time measuring values of the cutting force components graphically and to record the taken data to a text file.The measuring setup modernization enabled increasing measurement accuracy and reducing time for processing and analysis of experimental data obtained when measuring the cutting force components. The MT2 Department of BMSTU uses it in education and research activities and in experimental efforts and laboratory classes.

  9. Impact of Cutting Forces and Chip Microstructure in High Speed Machining of Carbon Fiber – Epoxy Composite Tube

    Directory of Open Access Journals (Sweden)

    Roy Y. Allwin

    2017-09-01

    Full Text Available Carbon fiber reinforced polymeric (CFRP composite materials are widely used in aerospace, automobile and biomedical industries due to their high strength to weight ratio, corrosion resistance and durability. High speed machining (HSM of CFRP material is needed to study the impact of cutting parameters on cutting forces and chip microstructure which offer vital inputs to the machinability and deformation characteristics of the material. In this work, the orthogonal machining of CFRP was conducted by varying the cutting parameters such as cutting speed and feed rate at high cutting speed/feed rate ranges up to 346 m/min/ 0.446 mm/rev. The impact of the cutting parameters on cutting forces (principal cutting, feed and thrust forces and chip microstructure were analyzed. A significant impact on thrust forces and chip segmentation pattern was seen at higher feed rates and low cutting speeds.

  10. Signatures of Self-Organized Criticality as System Forcing Changes

    Science.gov (United States)

    Woodard, R.; Newman, D.; Sanchez, R.; Carreras, B.

    2003-12-01

    Because of the broad claims of applicability made for self-organized criticality (SOC), it is important to define measurable characteristics which can validate or invalidate a statement that a system or model is SOC. We examine two such measures, spectral and R/S analysis, on a SOC sandpile model with varying driving rate and very long time records and find that: 1) the length of the data record can be crucial in distinguishing SOC from random dynamics, 2) R/S analysis gives a more consistent indication of the dynamics (whether correlated or not) in a SOC system than does the power spectrum, 3) a 1/f region in the SOC power spectrum does not arise from just a random superposition of events (pulses) from a power law distribution and 4) the 1/f spectrum can be substantially altered by keeping the same events and simply changing the spacing between them. The first result implies that SOC should not necessarily be discounted as a model for a geophysical process whose data do not match SOC signatures, since many such processes have long time scales that preclude the collection of relevantly long time series. The second result is an argument for including R/S analysis in one's standard toolbox when characterizing the dynamics of any physical system. The final two results imply a test to see if a process with a 1/f signal is possibly due to SOC.

  11. Identification of cutting force coefficients in machining process considering cutter vibration

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2004-01-01

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

  13. Cutting force analysis as a tool for evaluating the surface quality of machined parts

    International Nuclear Information System (INIS)

    Sanchez-Carrilero, M.; Marcos, M.; Alvarez-Alcon, M.; Sanchez-Corbacho, V.M.

    1998-01-01

    Surface quality is one of the most important criteria for establishing the optimum cutting parameters needed to perform a machining process. Usually, the evaluation of the degree of the surface finishing requires to apply metrological techniques which involve times out in the production. As a consequence of this, a loss in both the economy of the process and the fiability of the tests reproducibility can be produced. In this work a relation between cutting force and surface roughness has been studied for the turning process of an Al-Cu alloy. From this relation, the surface quality of the machined samples can be evaluated by using the cutting forces values acquired during the cutting process. (Author) 8 refs

  14. Measurement and prediction of cutting forces and vibrations on longwall shearers

    Energy Technology Data Exchange (ETDEWEB)

    Bulent Tiryaki [CRCMining (Australia)

    2006-12-15

    CRCMining has developed the Cutting Head Performance Analysis Software (CPAS) to predict cutter motor power, ranging arm reaction forces, and vibrations for different drum designs, coal seams, and shearer operational conditions. This project describes the work on THE DBT EL3000 shearer at Beltana to validate/update CPAS by measuring the cutter motor power, ranging arm vibrations, and reaction forces through an online data acquisition system called Cutting Head Performance Monitoring System (CPMS). This system records the outputs of six strain gauge bridges, six accelerometers, and two pressure transducers on ranging arms during underground coal production. CPAS2 has then been developed in order to eliminate the needs for performing coal cutting tests for the target coal seam. CPAS2 simulations for cutter motor power, vertical reaction force, and vibrations were also close to those measured in the trials. CRCMining will release the CPAS code including fully functioning software code on CD to Australian coal mining industry.

  15. Cutting force response in milling of Inconel: analysis by wavelet and Hilbert-Huang Transforms

    Directory of Open Access Journals (Sweden)

    Grzegorz Litak

    Full Text Available We study the milling process of Inconel. By continuously increasing the cutting depth we follow the system response and appearance of oscillations of larger amplitude. The cutting force amplitude and frequency analysis has been done by means of wavelets and Hilbert-Huang transform. We report that in our system the force oscillations are closely related to the rotational motion of the tool and advocate for a regenerative mechanism of chatter vibrations. To identify vibrations amplitudes occurrence in time scale we apply wavelet and Hilbert-Huang transforms.

  16. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes

    Directory of Open Access Journals (Sweden)

    Qiaokang Liang

    2016-01-01

    Full Text Available Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes.

  17. Design and Analysis of a Sensor System for Cutting Force Measurement in Machining Processes.

    Science.gov (United States)

    Liang, Qiaokang; Zhang, Dan; Coppola, Gianmarc; Mao, Jianxu; Sun, Wei; Wang, Yaonan; Ge, Yunjian

    2016-01-07

    Multi-component force sensors have infiltrated a wide variety of automation products since the 1970s. However, one seldom finds full-component sensor systems available in the market for cutting force measurement in machine processes. In this paper, a new six-component sensor system with a compact monolithic elastic element (EE) is designed and developed to detect the tangential cutting forces Fx, Fy and Fz (i.e., forces along x-, y-, and z-axis) as well as the cutting moments Mx, My and Mz (i.e., moments about x-, y-, and z-axis) simultaneously. Optimal structural parameters of the EE are carefully designed via simulation-driven optimization. Moreover, a prototype sensor system is fabricated, which is applied to a 5-axis parallel kinematic machining center. Calibration experimental results demonstrate that the system is capable of measuring cutting forces and moments with good linearity while minimizing coupling error. Both the Finite Element Analysis (FEA) and calibration experimental studies validate the high performance of the proposed sensor system that is expected to be adopted into machining processes.

  18. Analysis of surface roughness and cutting force during turning of Ti6Al4V ELI in dry environment

    Directory of Open Access Journals (Sweden)

    V. G. Sargade

    2016-04-01

    Full Text Available This paper investigates the effect of cutting parameters on the surface roughness and cutting force of titanium alloy Ti-6Al-4V ELI when turning using PVD TiAlN coated tool in dry environment. Taguchi L9 orthogonal array design of experiment was used for the turning experiment 2 factors and 3 levels. Turning parameters studied were cutting speed (50, 65, 80 m/min, feed rate (0.08, 0.15, 0.2 mm/rev and depth of cut 0.5 mm constant. Linear and second order model of the surface roughness and cutting force has been developed in terms of cutting speed and feed. The results show that the feed rate was the most impact factor controlling the cutting force and surface roughness produced. MINITAB 17software was used to develop a linear and second order model of surface roughness and cutting force. Optimum condition was at 66.97 m/min of cutting speed, 0.08 mm/rev of feed rate. Surface roughness 0.57μm and cutting force 54.02 N were obtained at the optimum condition. A good agreement between the experimental and predicted surface roughness and cutting force were observed.

  19. Improved method for the cutting coefficients calculation in micromilling force modeling

    NARCIS (Netherlands)

    Li, P.; Oosterling, J.A.J.; Hoogstrate, A.M.; Langen, H.H.

    2008-01-01

    This paper discusses the influence of runout on the calculation of the coefficients of mechanistic force models in micromilling. A runout mode is used to study the change of chip thickness, tool angles, and immersion period of two cutting edges of micro endmills due to runout. A new method to find

  20. Method for Friction Force Estimation on the Flank of Cutting Tools

    Directory of Open Access Journals (Sweden)

    Luis Huerta

    2017-01-01

    Full Text Available Friction forces are present in any machining process. These forces could play an important role in the dynamics of the system. In the cutting process, friction is mainly present in the rake face and the flank of the tool. Although the one that acts on the rake face has a major influence, the other one can become also important and could take part in the stability of the system. In this work, experimental identification of the friction on the flank is presented. The experimental determination was carried out by machining aluminum samples in a CNC lathe. As a result, two friction functions were obtained as a function of the cutting speed and the relative motion of the contact elements. Experiments using a worn and a new insert were carried out. Force and acceleration were recorded simultaneously and, from these results, different friction levels were observed depending on the cutting parameters, such as cutting speed, feed rate, and tool condition. Finally, a friction model for the flank friction is presented.

  1. A theoretical model for predicting the Peak Cutting Force of conical picks

    Directory of Open Access Journals (Sweden)

    Gao Kuidong

    2014-01-01

    Full Text Available In order to predict the PCF (Peak Cutting Force of conical pick in rock cutting process, a theoretical model is established based on elastic fracture mechanics theory. The vertical fracture model of rock cutting fragment is also established based on the maximum tensile criterion. The relation between vertical fracture angle and associated parameters (cutting parameter  and ratio B of rock compressive strength to tensile strength is obtained by numerical analysis method and polynomial regression method, and the correctness of rock vertical fracture model is verified through experiments. Linear regression coefficient between the PCF of prediction and experiments is 0.81, and significance level less than 0.05 shows that the model for predicting the PCF is correct and reliable. A comparative analysis between the PCF obtained from this model and Evans model reveals that the result of this prediction model is more reliable and accurate. The results of this work could provide some guidance for studying the rock cutting theory of conical pick and designing the cutting mechanism.

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

    Science.gov (United States)

    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.

  3. Experimental investigation and modelling of surface roughness and resultant cutting force in hard turning of AISI H13 Steel

    Science.gov (United States)

    Boy, M.; Yaşar, N.; Çiftçi, İ.

    2016-11-01

    In recent years, turning of hardened steels has replaced grinding for finishing operations. This process is compared to grinding operations; hard turning has higher material removal rates, the possibility of greater process flexibility, lower equipment costs, and shorter setup time. CBN or ceramic cutting tools are widely used hard part machining. For successful application of hard turning, selection of suitable cutting parameters for a given cutting tool is an important step. For this purpose, an experimental investigation was conducted to determine the effects of cutting tool edge geometry, feed rate and cutting speed on surface roughness and resultant cutting force in hard turning of AISI H13 steel with ceramic cutting tools. Machining experiments were conducted in a CNC lathe based on Taguchi experimental design (L16) in different levels of cutting parameters. In the experiments, a Kistler 9257 B, three cutting force components (Fc, Ff and Fr) piezoelectric dynamometer was used to measure cutting forces. Surface roughness measurements were performed by using a Mahrsurf PS1 device. For statistical analysis, analysis of variance has been performed and mathematical model have been developed for surface roughness and resultant cutting forces. The analysis of variance results showed that the cutting edge geometry, cutting speed and feed rate were the most significant factors on resultant cutting force while the cutting edge geometry and feed rate were the most significant factor for the surface roughness. The regression analysis was applied to predict the outcomes of the experiment. The predicted values and measured values were very close to each other. Afterwards a confirmation tests were performed to make a comparison between the predicted results and the measured results. According to the confirmation test results, measured values are within the 95% confidence interval.

  4. Some studies on cutting force and temperature in machining Ti-6Al-4V alloy using regression analysis and ANOVA

    Directory of Open Access Journals (Sweden)

    K.Satyanarayana

    2013-06-01

    Full Text Available The present work deals with the cutting forces and cutting temperature produced during turning of titanium alloy Ti-6Al-4V with PVD TiN coated tungsten carbide inserts under dry environment. The 1st order mathematical models are developed using multiple regression analysis and optimized the process parameters using contour plots. The model presented high determination coefficient (R2 = 0.964 and 0.989 explaining 96.4 % and 98.9 % of the variability in the cutting force and cutting temperature, which indicates the goodness of fit for the model and high significance of the model. The developed mathematical model correlates the relationship of the cutting force and temperature with the process parameters with good degree of approximation. From the contour plots, the optimal parametric combination for lowest cutting force is v 3 (75 m/min – f 1 (0.25 mm/rev. Similarly, the optimal parametric combination for minimum temperature is v 1 (45 m/min – f 1 (0.25 mm/rev. Cutting speed is found to be the most significance parameter on cutting forces followed by feed. Similarly, for cutting temperature, feed is found to be the most influencing parameter followed by cutting speed.

  5. The study on the nanomachining property and cutting model of single-crystal sapphire by atomic force microscopy.

    Science.gov (United States)

    Huang, Jen-Ching; Weng, Yung-Jin

    2014-01-01

    This study focused on the nanomachining property and cutting model of single-crystal sapphire during nanomachining. The coated diamond probe is used to as a tool, and the atomic force microscopy (AFM) is as an experimental platform for nanomachining. To understand the effect of normal force on single-crystal sapphire machining, this study tested nano-line machining and nano-rectangular pattern machining at different normal force. In nano-line machining test, the experimental results showed that the normal force increased, the groove depth from nano-line machining also increased. And the trend is logarithmic type. In nano-rectangular pattern machining test, it is found when the normal force increases, the groove depth also increased, but rather the accumulation of small chips. This paper combined the blew by air blower, the cleaning by ultrasonic cleaning machine and using contact mode probe to scan the surface topology after nanomaching, and proposed the "criterion of nanomachining cutting model," in order to determine the cutting model of single-crystal sapphire in the nanomachining is ductile regime cutting model or brittle regime cutting model. After analysis, the single-crystal sapphire substrate is processed in small normal force during nano-linear machining; its cutting modes are ductile regime cutting model. In the nano-rectangular pattern machining, due to the impact of machined zones overlap, the cutting mode is converted into a brittle regime cutting model. © 2014 Wiley Periodicals, Inc.

  6. Analysis of bit-rock interaction during stick-slip vibrations using PDC cutting force model

    Energy Technology Data Exchange (ETDEWEB)

    Patil, P.A.; Teodoriu, C. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE

    2013-08-01

    Drillstring vibration is one of the limiting factors maximizing the drilling performance and also causes premature failure of drillstring components. Polycrystalline diamond compact (PDC) bit enhances the overall drilling performance giving the best rate of penetrations with less cost per foot but the PDC bits are more susceptible to the stick slip phenomena which results in high fluctuations of bit rotational speed. Based on the torsional drillstring model developed using Matlab/Simulink for analyzing the parametric influence on stick-slip vibrations due to drilling parameters and drillstring properties, the study of relations between weight on bit, torque on bit, bit speed, rate of penetration and friction coefficient have been analyzed. While drilling with the PDC bits, the bit-rock interaction has been characterized by cutting forces and the frictional forces. The torque on bit and the weight on bit have both the cutting component and the frictional component when resolved in horizontal and vertical direction. The paper considers that the bit is undergoing stick-slip vibrations while analyzing the bit-rock interaction of the PDC bit. The Matlab/Simulink bit-rock interaction model has been developed which gives the average cutting torque, T{sub c}, and friction torque, T{sub f}, values on cutters as well as corresponding average weight transferred by the cutting face, W{sub c}, and the wear flat face, W{sub f}, of the cutters value due to friction.

  7. Assessment on F/W electrical cutting for reduction of electromagnetic force on the blanket module

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, Kazunori; Nishio, Satoshi; Koizumi, Kouichi; Takatsu, Hideyuki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Komatsuzaki, Manabu

    1996-07-01

    For mitigating the electromagnetic (EM) force acting on the first wall (F/W) during plasma disruption, effects of toroidally electrical cutting slits on copper heat sink of F/W have been investigated by EM analysis of the blanket module designed for the International Thermonuclear Experimental Reactor (ITER). The analytical studies include (1) effects of F/W material and its thickness on eddy current reduction, and (2) effects of number of toroidal cutting slits on copper heat sink and of gap length of the slit on the eddy current reduction in the copper heat sink. The following conclusions were obtained and the effectiveness of toroidal cutting of copper heat sink was clarified by a series of analyses; (a)A change of F/W material from copper alloy (DSCu) to SS316 decreases the eddy current and electromagnetic force on the F/W at plasma disruption. In the case of SS316, reduction effect is remarkable in the range of the thickness less than 50mm. (b)Toroidal cutting on F/W DSCu region can reduce total eddy current acting on the F/W. By increasing number of toroidal slits with 1mm gap length up to 17 (corresponding to maximum limit), about 60% of the eddy current in the F/W runs away through the SS316 support plate located at the behind of copper alloy heat sink. (author)

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

    Science.gov (United States)

    García Plaza, E.; Núñez López, P. J.

    2018-01-01

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

  9. Multi-objective optimization of surface roughness, cutting forces, productivity and Power consumption when turning of Inconel 718

    Directory of Open Access Journals (Sweden)

    Hamid Tebassi

    2016-01-01

    Full Text Available Nickel based super alloys are excellent for several applications and mainly in structural components submitted to high temperatures owing to their high strength to weight ratio, good corrosion resistance and metallurgical stability such as in cases of jet engine and gas turbine components. The current work presents the experimental investigations of the cutting parameters effects (cutting speed, depth of cut and feed rate on the surface roughness, cutting force components, productivity and power consumption during dry conditions in straight turning using coated carbide tool. The mathematical models for output parameters have been developed using Box-Behnken design with 15 runs and Box-Cox transformation was used for improving normality. The results of the analysis have shown that the surface finish was statistically sensitive to the feed rate and cutting speed with the contribution of 43.58% and 23.85% respectively, while depth of cut had the greatest effect on the evolution of cutting force components with the contribution of 79.87% for feed force, 66.92% for radial force and 66.26% for tangential force. Multi-objective optimization procedure allowed minimizing roughness Ra, cutting forces and power consumption and maximizing material removal rate using desirability approach.

  10. Cutting force and wear evaluation in peripheral milling by CVD diamond dental tools

    International Nuclear Information System (INIS)

    Polini, R.; Allegri, A.; Guarino, S.; Quadrini, F.; Sein, H.; Ahmed, W.

    2004-01-01

    Co-cemented tungsten carbide (WC-Co) tools are currently employed in dental application for prosthesis fabrication. The deposition of a diamond coating onto WC-Co tools could allow both to increase the tool life and tool performance at higher speeds. However, at present it is very difficult to quantify the effective advantage of the application of a diamond coating onto dental tools compared to traditional uncoated tools. Therefore, in this work, we have deposited diamond coatings onto WC-Co dental tools having different geometries by Hot Filament Chemical Vapour Deposition (HFCVD). Prior to deposition, the WC-Co tools were pre-treated in order to roughen the surface and to modify the chemical surface composition. The use of the HFCVD process enabled the deposition of a uniform coating despite the complex geometries of the dental mills. For the first time, in accordance to the knowledge of the authors, we have studied and compared the cutting behaviour of both virgin and diamond-coated dental tools by measuring both wear and cutting force time evolution under milling a very hard Co-Cr-Mo dental alloy. To ensure constant cutting rate (20,000-r.p.m. cutting rate, 0.01-m/min feed rate and 0.5-mm depth of cut), a proper experimental apparatus was used. Three different mill geometries were considered in both coated and uncoated conditions. The results showed that, under the high-speed conditions employed, uncoated tools underwent to catastrophic failure within a few seconds of machining. Diamond-coated tools exhibited much longer tool lives. Lower forces were measured when the coated tool was employed due to the much lower material-mill friction. The best behaviour was observed for coated mills with the presence of a chip-breaker

  11. Penetration force, geometry, and cutting profile of the novel and old Ozurdex needle: the MONO study.

    Science.gov (United States)

    Meyer, Carsten H; Liu, Zengping; Brinkmann, Christian K; Rodrigues, Eduardo B; Bertelmann, Thomas

    2014-06-01

    To investigate the geometry, penetration force, and cutting profile of the novel and old needle of the drug delivery system (DDS) for Ozurdex injections in a standardized laboratory setting. In this experimental study, the normative geometrical data of the DDS needle were systematically analyzed according to nomenclature DIN 13097 (ISO 7864) and ISO 9626. The force to penetrate a standardized 0.4-mm-thick polyurethane foil was measured by a penetrometer, when the needle was piercing, cutting, and sliding through the foil and plotted as a load-displacement diagram. Magnified images of the consecutive cut were taken after the entire penetration through the foil. In this experimental study, the mean point length was equal to 3.34 mm (3.28-3.36 mm) for the old DDS needle versus 3.33 mm (3.30-3.36 mm) for the new DDS needle. The secondary bevel length was 1.64 mm (1.42-1.73 mm) for the new and 1.66 mm (1.62-1.69 mm) for the old needle. The primary angle was 9.2° (9.0°-9.5°) for the old and 8.9° (8.5°-9.0°) for the new needle, respectively. The secondary bevel angle was 117.2° (116°-118°) for the old and 111.4° (110°-113°) for the new needle. The mean penetration force of the old DDS needles was significantly higher at all phases of the penetration experiment: The mean piercing force was 0.7 Newton (N) with the old and 0.47 N with the new DDS needle. The mean cutting force was remarkable higher with 1.1 N for the old DDS needle versus 0.78 N for the new DDS needle. The dilatation phase was not statistically significant between 0.94 and 0.99 N in both DDS needles. The friction phase was maintained at significantly higher levels with the old DDS needle of 0.47 N, whereas it returned to the lowest measurements of 0.11 N with the new DDS needle. Both DDS systems induced a characteristic chevron-shaped incision. A comparison of the old and new DDS needles demonstrated a reduced penetration force with the modified new DDS needle, which may help to achieve a smooth

  12. The effects of femoral neck cut, cable tension, and muscles forces on the greater trochanter fixation.

    Science.gov (United States)

    Petit, Yvan; Cloutier, Luc P; Duke, Kajsa; Laflamme, G Yves

    2012-04-01

    Greater trochanter (GT) stabilization techniques following a fracture or an osteotomy are still showing high levels of postoperative complications. Understanding the effect of femoral neck cut placement, cable tension and muscles forces on GT fragment displacements could help surgeons optimize their techniques. A 3D finite element model has been developed to evaluate, through a statistical experimental design, the impact of the above variables on the GT fragment gap and sliding displacements. Muscles forces were simulating typical daily activities. Stresses were also investigated. The femoral neck cut placement had the most significant effect on the fragment displacement. Lowering it by 5 mm increased the gap and sliding fragment displacements by 288 and 128 %, respectively. Excessive cable tightening provided no significant reduction in fragment displacement. Muscle activities increased the gap and the sliding displacements for all muscle configurations. The maximum total displacement of 0.41 mm was present with a 10 mm femoral neck cut, a cable tension of 178 N, and stair climbing. Caution must be used not to over tighten the cables as the potential damage caused by the increased stress is more significant than any reduction in fragment displacement. Furthermore, preservation of the contact area is important for GT stabilization.

  13. Force signature of the unzipping transition for strip confined two-dimensional polymers

    Science.gov (United States)

    Owczarek, Aleksander L.; Rechnitzer, Andrew

    2017-12-01

    We find and analyse the exact solution of two friendly walks, modelling polymers, confined between two parallel walls in a two-dimensional strip (or slit) where the polymers interact with each other via an attractive contact interaction. In the bulk, where the polymers are always far from any walls, there is an unzipping transition between phases where the two walks drift away for low attractive fugacity (high temperatures) and bind together for high attractive fugacities (low temperatures). Previously this has been used to model the denaturation of DNA. In a strip the transition is not sharp. However, we demonstrate that there is an abrupt change in the repulsive force exerted on the walls of the strip that can be calculated exactly. We suggest that this change in the force could be exploited to provide an experimental signature of the unzipping transition.

  14. Internally displaced "victims of armed conflict" in Colombia: the trajectory and trauma signature of forced migration.

    Science.gov (United States)

    Shultz, James M; Garfin, Dana Rose; Espinel, Zelde; Araya, Ricardo; Oquendo, Maria A; Wainberg, Milton L; Chaskel, Roberto; Gaviria, Silvia L; Ordóñez, Anna E; Espinola, Maria; Wilson, Fiona E; Muñoz García, Natalia; Gómez Ceballos, Angela Milena; Garcia-Barcena, Yanira; Verdeli, Helen; Neria, Yuval

    2014-10-01

    While conflict-induced forced migration is a global phenomenon, the situation in Colombia, South America, is distinctive. Colombia has ranked either first or second in the number of internally displaced persons for 10 years, a consequence of decades of armed conflict compounded by high prevalence of drug trafficking. The displacement trajectory for displaced persons in Colombia proceeds through a sequence of stages: (1) pre-expulsion threats and vulnerability, (2) expulsion, (3) migration, (4) initial adaptation to relocation, (5) protracted resettlement (the end point for most forced migrants), and, rarely, (6) return to the community of origin. Trauma signature analysis, an evidence-based method that elucidates the physical and psychological consequences associated with exposures to harm and loss during disasters and complex emergencies, was used to identify the psychological risk factors and potentially traumatic events experienced by conflict-displaced persons in Colombia, stratified across the phases of displacement. Trauma and loss are experienced differentially throughout the pathway of displacement.

  15. Evaluation of cutting force and surface roughness in high-speed milling of compacted graphite iron

    Directory of Open Access Journals (Sweden)

    Azlan Suhaimi Mohd

    2017-01-01

    Full Text Available Compacted Graphite Iron, (CGI is known to have outstanding mechanical strength and weight-to-strength ratio as compared to conventional grey cast iron, (CI. The outstanding characteristics of CGI is due to its graphite particle shape, which is presented as compacted vermicular particle. The graphite is interconnected with random orientation and round edges, which results in higher mechanical strength. Whereas, graphite in the CI consists of a smooth-surfaced flakes that easily propagates cracks which results in weaker and brittle properties as compared to CGI. Owing to its improved properties, CGI is considered as the best candidate material in substituting grey cast iron that has been used in engine block applications for years. However, the smooth implementation of replacing CI with CGI has been hindered due to the poor machinability of CGI especially at high cutting speed. The tool life is decreased by 20 times when comparing CGI with CI under the same cutting condition. This study investigates the effect of using cryogenic cooling and minimum quantity lubrication (MQL during high-speed milling of CGI (grade 450. Results showed that, the combination of internal cryogenic cooling and enhanced MQL improved the tool life, cutting force and surface quality as compared to the conventional flood coolant strategy during high-speed milling of CGI.

  16. Characteristics and time-dependence of cut marks and blunt force fractures on costal cartilages: an experimental study.

    Science.gov (United States)

    Spagnoli, Laura; Amadasi, Alberto; Frustaci, Michela; Mazzarelli, Debora; Porta, Davide; Cattaneo, Cristina

    2016-03-01

    The distinction between cut marks and blunt force injuries on costal cartilages is a crucial issue in the forensic field. Moreover, a correct distinction may further be complicated by decomposition, so the need arises to investigate the distinctive features of lesions on cartilage and their changes over time. This study aimed to assess the stereomicroscopic features of cut marks (performed with six different knives) and blunt fractures (performed with a hammer and by means of manual bending) on 48 fragments of human costal cartilages. Moreover, in order to simulate decomposition, the cut and fractured surfaces were checked with stereomicroscopy and through casts after 1 and 2 days, 1 week, and 1, 2 and 4 months of drying in ambient air. In fresh samples, for single and unique cuts, striations were observed in between 44 and 88% of cases when non-serrated blades were used, and between 77 and 88% for serrated blades; in the case of "repeated" (back and forth movement) cuts, striations were detected in between 56 and 89% of cases for non-serrated blades, and between 66 and 100% for serrated blades. After only 1 week of decomposition the detection rates fell to percentages of between 28 and 39% for serrated blades and between 17 and 33% for non-serrated blades. Blunt force injuries showed non-specific characteristics, which, if properly assessed, may lead to a reliable distinction between different cut marks in fresh samples. The most evident alterations of the structure of the cartilage occurred in the first week of decomposition in ambient air. After one week of drying, the characteristics of cut marks were almost undetectable, thereby making it extremely challenging to distinguish between cut marks, blunt force fractures and taphonomic effects. The study represents a contribution to the correct assessment and distinction of cut marks and blunt force injuries on cartilages, providing a glimpse on the modifications such lesions may undergo with decomposition.

  17. Establishment of performance standards and a cut-score for the Canadian Forces firefighter physical fitness maintenance evaluation (FF PFME).

    Science.gov (United States)

    Todd Rogers, W; Docherty, David; Petersen, Stewart

    2014-01-01

    The bookmark method for setting cut-scores was used to re-set the cut-score for the Canadian Forces Firefighter Physical Fitness Maintenance Evaluation (FF PFME). The time required to complete 10 tasks that together simulate a first-response firefighting emergency was accepted as a measure of work capacity. A panel of 25 Canadian Forces firefighter supervisors set cut-scores in three rounds. Each round involved independent evaluation of nine video work samples, where the times systematically increased from 400 seconds to 560 seconds. Results for Round 1 were discussed before moving to Round 2 and results for Round 2 were discussed before moving to Round 3. Accounting for the variability among panel members at the end of Round 3, a cut-score of 481 seconds (mean Round 3 plus 2 SEM) was recommended. Firefighters who complete the FF PFME in 481 seconds or less have the physical capacity to complete first-response firefighting work.

  18. Influence of axial feed in hobbing with minimal quantity lubrication (MQL on wear of the hob and cutting forces

    Directory of Open Access Journals (Sweden)

    Wojciech STACHURSKI

    2015-12-01

    Full Text Available In the paper evaluation of the influence of axial feed on the hob wear in hobbing with minimal quantity lubrication technique has been done. As a work material C45 carbon steel has been investigated. Wear resistance of the hob made from high speed steel HS6-5-2 without coating has been investigated. For comparison tests with conventional fluid supply method have been carried out. Gears have been generated with full depth of cut and with two axial feed with constant cutting speed value. During hobbing cutting forces have been measured by experimental stand. Tool wear has been measured directly as a width of flank wear land of the hob cutter teeth. During investigation any significant wear changes on the rake faces haven’t been detected, so those results haven’t been taken into consideration. A constant length of cut parameter has been established as a criteria value. Results of investigation have been presented in the form of graphs describing changes of wear land width parameter in comparison to the most loaded tooth wear land parameter. Also changes of cutting forces in time are presented too. On the base of obtained results conclusion has been formulated that MQL technique might be used as an alternative solution for supplying cutting fluid into the cutting zone during hobbing process.

  19. Do rotational shear-cushioning shoes influence horizontal ground reaction forces and perceived comfort during basketball cutting maneuvers?

    Directory of Open Access Journals (Sweden)

    Wing-Kai Lam

    2017-11-01

    Full Text Available Background Court shoe designs predominantly focus on reducing excessive vertical ground reaction force, but shear force cushioning has received little attention in the basketball population. We aimed to examine the effect of a novel shoe-cushioning design on both resultant horizontal ground reaction forces and comfort perception during two basketball-specific cutting movements. Methods Fifteen university team basketball players performed lateral shuffling and 45-degree sidestep cutting at maximum effort in basketball shoes with and without the shear-cushioning system (SCS. Paired t-tests were used to examine the differences in kinetics and comfort perception between two shoes. Results SCS shoe allowed for larger rotational material deformation compared with control shoes, but no significant shoe differences were found in braking phase kinetics during both cutting movements (P = 0.35. Interestingly, a greater horizontal propulsion impulse was found with the SCS during 45-degree cutting (P  0.05. Discussion The application of a rotational shear-cushioning structure allowed for better forefoot comfort and enhanced propulsion performance in cutting, but did not influence the shear impact. Understanding horizontal ground reaction force information may be useful in designing footwear to prevent shear-related injuries in sport populations.

  20. Evaluation of the Cutting Force Components and the Surface Roughness in the Milling Process of Micro- and Nanocrystalline Titanium

    Directory of Open Access Journals (Sweden)

    Habrat W.

    2016-09-01

    Full Text Available Nanocristalline pure titanium in comparison to microcrystalline titanium is characterized by better mechanical properties which influence its wider usability. The aim of the research was to evaluate whether the grain size of pure titanium (micro- and nanocrystalline has influence on the cutting force components and the surface roughness in the milling process. Models of cutting force components for both materials were prepared and differences between the results were examined. The feed rate effect on selected parameters of surface roughness after milling of micro- and nanocrystalline pure titanium was determined.

  1. An investigation of force components in orthogonal cutting of medical grade cobalt-chromium alloy (ASTM F1537).

    Science.gov (United States)

    Baron, Szymon; Ahearne, Eamonn

    2017-04-01

    An ageing population, increased physical activity and obesity are identified as lifestyle changes that are contributing to the ongoing growth in the use of in-vivo prosthetics for total hip and knee arthroplasty. Cobalt-chromium-molybdenum (Co-Cr-Mo) alloys, due to their mechanical properties and excellent biocompatibility, qualify as a class of materials that meet the stringent functional requirements of these devices. To cost effectively assure the required dimensional and geometric tolerances, manufacturers rely on high-precision machining. However, a comprehensive literature review has shown that there has been limited research into the fundamental mechanisms in mechanical cutting of these alloys. This article reports on the determination of the basic cutting-force coefficients in orthogonal cutting of medical grade Co-Cr-Mo alloy ASTM F1537 over an extended range of cutting speeds ([Formula: see text]) and levels of undeformed chip thickness ([Formula: see text]). A detailed characterisation of the segmented chip morphology over this range is also reported, allowing for an estimation of the shear plane angle and, overall, providing a basis for macro-mechanic modelling of more complex cutting processes. The results are compared with a baseline medical grade titanium alloy, Ti-6Al-4V ASTM F136, and it is shown that the tangential and thrust-force components generated were, respectively, ≈35% and ≈84% higher, depending primarily on undeformed chip thickness but with some influence of the cutting speed.

  2. Mathematical Modelling and Optimization of Cutting Force, Tool Wear and Surface Roughness by Using Artificial Neural Network and Response Surface Methodology in Milling of Ti-6242S

    Directory of Open Access Journals (Sweden)

    Erol Kilickap

    2017-10-01

    Full Text Available In this paper, an experimental study was conducted to determine the effect of different cutting parameters such as cutting speed, feed rate, and depth of cut on cutting force, surface roughness, and tool wear in the milling of Ti-6242S alloy using the cemented carbide (WC end mills with a 10 mm diameter. Data obtained from experiments were defined both Artificial Neural Network (ANN and Response Surface Methodology (RSM. ANN trained network using Levenberg-Marquardt (LM and weights were trained. On the other hand, the mathematical models in RSM were created applying Box Behnken design. Values obtained from the ANN and the RSM was found to be very close to the data obtained from experimental studies. The lowest cutting force and surface roughness were obtained at high cutting speeds and low feed rate and depth of cut. The minimum tool wear was obtained at low cutting speed, feed rate, and depth of cut.

  3. Cutting forces optimization in the turning of UD-GFRP composites ...

    African Journals Online (AJOL)

    This paper presents an effective approach for the optimization of turning parameters based on the Taugchi's method with regression analysis. Second order predictive model covering tool nose radius, tool rake angle, feed rate, cutting speed, cutting environment (dry, wet and cooled) and depth of cut has been developed at ...

  4. Tool Forces and Chip Formation In Orthogonal Cutting Of Loblolly Pine

    Science.gov (United States)

    George E. Woodson; Peter Koch

    1970-01-01

    Specimens of earlywood and latewood of Pinus taeda L. were excised so that length along the grain was 3 inches and thickness was 0.1 inch. These specimens were cut orthogonally-as with a carpenter's plane-in the three major directions. Cutting velocity was 2 inches per minute. When cutting was in the planing (90-O) direction, thin chips,...

  5. Defining the effect of sweep tillage tool cutting edge geometry on tillage forces using 3D discrete element modelling

    Directory of Open Access Journals (Sweden)

    Mustafa Ucgul

    2015-09-01

    Full Text Available The energy required for tillage processes accounts for a significant proportion of total energy used in crop production. In many tillage processes decreasing the draft and upward vertical forces is often desired for reduced fuel use and improved penetration, respectively. Recent studies have proved that the discrete element modelling (DEM can effectively be used to model the soil–tool interaction. In his study, Fielke (1994 [1] examined the effect of the various tool cutting edge geometries, namely; cutting edge height, length of underside rub, angle of underside clearance, on draft and vertical forces. In this paper the experimental parameters of Fielke (1994 [1] were simulated using 3D discrete element modelling techniques. In the simulations a hysteretic spring contact model integrated with a linear cohesion model that considers the plastic deformation behaviour of the soil hence provides better vertical force prediction was employed. DEM parameters were determined by comparing the experimental and simulation results of angle of repose and penetration tests. The results of the study showed that the simulation results of the soil-various tool cutting edge geometries agreed well with the experimental results of Fielke (1994 [1]. The modelling was then used to simulate a further range of cutting edge geometries to better define the effect of sweep tool cutting edge geometry parameters on tillage forces. The extra simulations were able to show that by using a sharper cutting edge with zero vertical cutting edge height the draft and upward vertical force were further reduced indicating there is benefit from having a really sharp cutting edge. The extra simulations also confirmed that the interpolated trends for angle of underside clearance as suggested by Fielke (1994 [1] where correct with a linear reduction in draft and upward vertical force for angle of underside clearance between the ranges of −25 and −5°, and between −5 and 0°. The

  6. The influence of cooling techniques on cutting forces and surface roughness during cryogenic machining of titanium alloys

    Directory of Open Access Journals (Sweden)

    Wstawska Iwona

    2016-12-01

    Full Text Available Titanium alloys are one of the materials extensively used in the aerospace industry due to its excellent properties of high specific strength and corrosion resistance. On the other hand, they also present problems wherein titanium alloys are extremely difficult materials to machine. In addition, the cost associated with titanium machining is also high due to lower cutting velocities and shorter tool life. The main objective of this work is a comparison of different cooling techniques during cryogenic machining of titanium alloys. The analysis revealed that applied cooling technique has a significant influence on cutting force and surface roughness (Ra parameter values. Furthermore, in all cases observed a positive influence of cryogenic machining on selected aspects after turning and milling of titanium alloys. This work can be also the starting point to the further research, related to the analysis of cutting forces and surface roughness during cryogenic machining of titanium alloys.

  7. Influence of anatomy and basic density on specific cutting force for wood from Corymbia citriodora Hill & Johnson

    Directory of Open Access Journals (Sweden)

    Luiz-E. de L. Melo

    2015-12-01

    Full Text Available Aim of the study: The aim of this study was to evaluate the influence of xylem tissue cell structure, determined through biometry and basic density of the wood from Corymbia citriodora Hill & Johnson on consumption of specific 90º-0º longitudinal cutting force.Area of study: The study area was in the region of the Vale do Rio Doce - Minas Gerais, Brazil.Material and methods: A diametrical board with dimensions of 60 x 18 x 5 cm (length x width x thickness, respectively, with more than 1.3 m from the ground, was removed. In machining trials, a 400 mm diameter circular saw was used, with 24 “WZ” teeth, feed rate of 10 m.min-1, cutting speed of 61 m.s-1, and maximum instantaneous torque of 92.5 N.m. During cutting, test specimens were removed with alternated and parallel 1.5 cm edges in 6 radial positions, which were used for biometric determination of cell structure and basic density.Main results: It was observed that wood basic density, vessel diameter, fiber wall thickness, fiber wall fraction and fiber wall portion were directly proportional to the specific cutting force. In contrast, vessel frequency and fiber lumen diameter proved to be inversely proportional to cutting force.Research highlights: This work provides important values of quantification of influence of xylem tissue cell structure, determined through biometry and physical properties of the wood that may be used to prediction of consumption of specific cutting force.Keywords: wood machining; wood properties; optimization of the process.

  8. Evaluation of Tool Path Strategy and Cooling Condition Effects on the Cutting Force and Surface Quality in Micromilling Operations

    Directory of Open Access Journals (Sweden)

    Ugur Koklu

    2017-10-01

    Full Text Available Compared to milling on a macro scale, the micromilling process has several cumbersome points that need to be addressed. Rapid tool wear and fracture, severe burr formation, and poor surface quality are the major problems encountered in the micromilling process. This study aimed to reveal the effect of cutting path strategies on the cutting force and surface quality in the micromilling of a pocket. The hatch zigzag tool path strategy and the contour climb tool path strategy under different cooling conditions (e.g., dry, air blow, and flood coolant at fixed cutting parameters. The micromilling tests revealed that better results were obtained with the use of the contour tool path strategy in terms of cutting forces (by up to ~43% compared to the dry condition and surface quality (by up to ~44% compared to the air blow condition when compared to the hatch tool path strategy. In addition, the flood coolant reduces the cutting temperature and eliminates chips to significantly enhance the quality of the micro milled surface.

  9. Finite Element Analysis Of Influence Of Flank Wear Evolution On Forces In Orthogonal Cutting Of 42CrMo4 Steel

    Science.gov (United States)

    Madajewski, Marek; Nowakowski, Zbigniew

    2017-01-01

    This paper presents analysis of flank wear influence on forces in orthogonal turning of 42CrMo4 steel and evaluates capacity of finite element model to provide such force values. Data about magnitude of feed and cutting force were obtained from measurements with force tensiometer in experimental test as well as from finite element analysis of chip formation process in ABAQUS/Explicit software. For studies an insert with complex rake face was selected and flank wear was simulated by grinding operation on its flank face. The aim of grinding inset surface was to obtain even flat wear along cutting edge, which after the measurement could be modeled with CAD program and applied in FE analysis for selected range of wear width. By comparing both sets of force values as function of flank wear in given cutting conditions FEA model was validated and it was established that it can be applied to analyze other physical aspects of machining. Force analysis found that progression of wear causes increase in cutting force magnitude and steep boost to feed force magnitude. Analysis of Fc/Ff force ratio revealed that flank wear has significant impact on resultant force in orthogonal cutting and magnitude of this force components in cutting and feed direction. Surge in force values can result in transfer of substantial loads to machine-tool interface.

  10. Finite Element Analysis Of Influence Of Flank Wear Evolution On Forces In Orthogonal Cutting Of 42CrMo4 Steel

    Directory of Open Access Journals (Sweden)

    Madajewski Marek

    2017-01-01

    Full Text Available This paper presents analysis of flank wear influence on forces in orthogonal turning of 42CrMo4 steel and evaluates capacity of finite element model to provide such force values. Data about magnitude of feed and cutting force were obtained from measurements with force tensiometer in experimental test as well as from finite element analysis of chip formation process in ABAQUS/Explicit software. For studies an insert with complex rake face was selected and flank wear was simulated by grinding operation on its flank face. The aim of grinding inset surface was to obtain even flat wear along cutting edge, which after the measurement could be modeled with CAD program and applied in FE analysis for selected range of wear width. By comparing both sets of force values as function of flank wear in given cutting conditions FEA model was validated and it was established that it can be applied to analyze other physical aspects of machining. Force analysis found that progression of wear causes increase in cutting force magnitude and steep boost to feed force magnitude. Analysis of Fc/Ff force ratio revealed that flank wear has significant impact on resultant force in orthogonal cutting and magnitude of this force components in cutting and feed direction. Surge in force values can result in transfer of substantial loads to machine-tool interface.

  11. The influence of tool path strategies on cutting force and surface texture during ball end milling of low curvature convex surfaces.

    Science.gov (United States)

    Shajari, Shaghayegh; Sadeghi, Mohammad Hossein; Hassanpour, Hamed

    2014-01-01

    Advancement in machining technology of curved surfaces for various engineering applications is increasing. Various methodologies and computer tools have been developed by the manufacturers to improve efficiency of freeform surface machining. Selection of the right sets of cutter path strategies and appropriate cutting conditions is extremely important in ensuring high productivity rate, meeting the better quality level, and lower cutting forces. In this paper, cutting force as a new decision criterion for the best selection of tool paths on convex surfaces is presented. Therefore, this work aims at studying and analyzing different finishing strategies to assess their influence on surface texture, cutting forces, and machining time. Design and analysis of experiments are performed by means of Taguchi technique and analysis of variance. In addition, the significant parameters affecting the cutting force in each strategy are introduced. Machining strategies employed include raster, 3D-offset, radial, and spiral. The cutting parameters were feed rate, cutting speed, and step over. The experiments were carried out on low curvature convex surfaces of stainless steel 1.4903. The conclusion is that radial strategy provokes the best surface texture and the lowest cutting forces and spiral strategy signifies the worst surface texture and the highest cutting forces.

  12. 3D Finite Element Modelling of Cutting Forces in Drilling Fibre Metal Laminates and Experimental Hole Quality Analysis

    Science.gov (United States)

    Giasin, Khaled; Ayvar-Soberanis, Sabino; French, Toby; Phadnis, Vaibhav

    2017-02-01

    Machining Glass fibre aluminium reinforced epoxy (GLARE) is cumbersome due to distinctively different mechanical and thermal properties of its constituents, which makes it challenging to achieve damage-free holes with the acceptable surface quality. The proposed work focuses on the study of the machinability of thin ( 2.5 mm) GLARE laminate. Drilling trials were conducted to analyse the effect of feed rate and spindle speed on the cutting forces and hole quality. The resulting hole quality metrics (surface roughness, hole size, circularity error, burr formation and delamination) were assessed using surface profilometry and optical scanning techniques. A three dimensional (3D) finite-element (FE) model of drilling GLARE laminate was also developed using ABAQUS/Explicit to help understand the mechanism of drilling GLARE. The homogenised ply-level response of GLARE laminate was considered in the FE model to predict cutting forces in the drilling process.

  13. A protocol to correct for intra- and interspecific variation in tail hair growth to align isotope signatures of segmentally cut tail hair to a common time line.

    Science.gov (United States)

    Burnik Šturm, Martina; Pukazhenthi, Budhan; Reed, Dolores; Ganbaatar, Oyunsaikhan; Sušnik, Stane; Haymerle, Agnes; Voigt, Christian C; Kaczensky, Petra

    2015-06-15

    In recent years, segmental stable isotope analysis of hair has been a focus of research in animal dietary ecology and migration. To correctly assign tail hair segments to seasons or even Julian dates, information on tail hair growth rates is a key parameter, but is lacking for most species. We (a) reviewed the literature on tail hair growth rates in mammals; b) made own measurements of three captive equid species; (c) measured δ(2)H, δ(13)C and δ(15)N values in sequentially cut tail hairs of three sympatric, free-ranging equids from the Mongolian Gobi, using isotope ratio mass spectrometry (IRMS); and (d) collected environmental background data on seasonal variation by measuring δ(2)H values in precipitation by IRMS and by compiling pasture productivity measured by remote sensing via the normalized difference vegetation index (NDVI). Tail hair growth rates showed significant inter- and intra-specific variation making temporal alignment problematic. In the Mongolian Gobi, high seasonal variation of δ(2)H values in precipitation results in winter lows and summer highs of δ(2)H values of available water sources. In water-dependent equids, this seasonality is reflected in the isotope signatures of sequentially cut tails hairs. In regions which are subject to strong seasonal patterns we suggest identifying key isotopes which show strong seasonal variation in the environment and can be expected to be reflected in the animal tissue. The known interval between the maxima and minima of these isotope values can then be used to correctly temporally align the segmental stable isotope signature for each individual animal. © 2015 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd.

  14. EXPERIMENTAL INVESTIGATION OF THE EFFECT OF MACHINIG PARAMETERS OVER CUTTING FORCE AND SURFACE ROUGHNESS IN THE MACHINABILITY OF AA5052 ALLOY

    Directory of Open Access Journals (Sweden)

    Hasan GÖKKAYA

    2006-03-01

    Full Text Available In this study, the effects of different cutting and feed rates over average surface roughness and main cutting force during the machinability of AA5052 aluminum alloy with uncoated cemented carbide insert were evaluated. In the experiments, stable depth of cut (1.5 mm, four different cutting speeds (200, 300, 400, 500 m/min and five different feed rates (0.10, 0.15, 0.20, 0.25, 0.30 mm/rev were used. Based on cutting and feed rates, the lowest main cutting force was obtained as 113 in 500 m/min cutting speed and 0.10 mm/rev feed rate and the highest cutting force was obtained as 332 N in 200 m/min cutting speed and 0.30 mm/rev feed rate. The lowest average surface roughness was obtained as 0.95 µm in 200 m/min cutting speed and 0.10 mm/rev feed rate and the highest average surface roughness was obtained as 6.65 µm in 300 m/min cutting speed and 0.30 mm/rev feed rate.

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

    Science.gov (United States)

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

    2018-02-01

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

  16. Finite Element Modelling of the effect of tool rake angle on tool temperature and cutting force during high speed machining of AISI 4340 steel

    Science.gov (United States)

    Sulaiman, S.; Roshan, A.; Ariffin, M. K. A.

    2013-12-01

    In this paper, a Finite Element Method (FEM) based on the ABAQUS explicit software which involves Johnson-Cook material model was used to simulate cutting force and tool temperature during high speed machining (HSM) of AISI 4340 steel. In this simulation work, a tool rake angle ranging from 0° to 20° and a range of cutting speeds between 300 to 550 m/min was investigated. The purpose of this simulation analysis was to find optimum tool rake angle where cutting force is smallest as well as tool temperature is lowest during high speed machining. It was found that cutting forces to have a decreasing trend as rake angle increased to positive direction. The optimum rake angle observed between 10° and 18° due to decrease of cutting force as 20% for all simulated cutting speeds. In addition, increasing cutting tool rake angle over its optimum value had negative influence on tool's performance and led to an increase in cutting temperature. The results give a better understanding and recognition of the cutting tool design for high speed machining processes.

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

    OpenAIRE

    Norman, D. G.; Watson, Derrick G.; Burnett, B.; Fenne, P. M.; Williams, M. A. (Mark A.)

    2018-01-01

    Toolmark analysis involves examining marks created on an object to identify the likely tool responsible for creating those marks (e.g., a knife). Although a potentially powerful forensic tool, knife mark analysis is still in its infancy and the validation of imaging techniques as well as quantitative approaches is ongoing. This study builds on previous work by simulating real-world stabbings experimentally and statistically exploring quantitative toolmark properties, such as cut mark angle ca...

  18. EVALUATION OF MACHINABILITY OF DUCTILE IRONS ALLOYED WITH Ni AND Cu IN TERMS OF CUTTING FORCES AND SURFACE QUALITY

    Directory of Open Access Journals (Sweden)

    Yücel AŞKUN

    2003-02-01

    Full Text Available Due to the enhanced strength, ductility and thoughness of Ductile Iron (DI when compared to the other types cast iron, its machinability is relatively poor. When a steel part is replaced with ductile iron, however, better machinability is considered to be the most important gain. This study presents the results of machining tests of ductile irons alloyed with Ni and Cu at various contents to determine the effect of their microstructure and mechanical properties on cutting forces and surface roughness. Six different specimen groups of ductile iron alloyed with various amounts of nickel and copper were subjected to machining tests and their machinabilities were investigated based on cutting forces and surface roughness criteria. The results were evaluated according to microstructure and mechanical properties of specimens determined before. In terms of both criterion, the best result obtained was specimen added 0.7 % Ni and 0.7 % Cu. When the specimens were evaluated according to their mechanical properties, the specimens alloyed 1 % Ni and 0.65 % Cu seemed promising.

  19. CHANGE@CERN:Task Force 1: finding the least painful cuts

    CERN Multimedia

    2002-01-01

    This week sees the first in our series of reports on the work of the Task Forces By 2004, COMPASS will be the main experiment at the SPS, but the LHC experiments will also be calibrating detectors. 'It was a painful task, with which we had to proceed in the least damaging way', says Dieter Schlatter, Head of the EP Division, when describing his experience as Convenor of Task Force 1. This Task Force was charged with responsibility for advising on how money could be saved within CERN's research programme, in order to help deal with the increased cost to completion of the LHC project. Their role, as with the other Task Forces, was to suggest where savings could be made, and in most cases their suggestions have been incorporated in the Management's draft Long Term Plan. The pain of the task was to some extent alleviated by developments within the LHC project itself. Delays in the delivery of superconducting cable meant that the start up of the LHC would be delayed by a year, to 2007, and this gave Task Force ...

  20. Internally Displaced “Victims of Armed Conflict” in Colombia: The Trajectory and Trauma Signature of Forced Migration

    Science.gov (United States)

    Shultz, James M.; Garfin, Dana Rose; Espinel, Zelde; Araya, Ricardo; Oquendo, Maria A.; Wainberg, Milton L.; Chaskel, Roberto; Gaviria, Silvia L.; Ordóñez, Anna E.; Espinola, Maria; Wilson, Fiona E.; García, Natalia Muñoz; Ceballos, Ángela Milena Gómez; Garcia-Barcena, Yanira; Verdeli, Helen; Neria, Yuval

    2016-01-01

    While conflict-induced forced migration is a global phenomenon, the situation in Colombia, South America, is distinctive. Colombia has ranked either first or second in the number of internally displaced persons for 10 years, a consequence of decades of armed conflict compounded by high prevalence of drug trafficking. The displacement trajectory for displaced persons in Colombia proceeds through a sequence of stages: (1) pre-expulsion threats and vulnerability, (2) expulsion, (3) migration, (4) initial adaptation to relocation, (5) protracted resettlement (the end point for most forced migrants), and, rarely, (6) return to the community of origin. Trauma signature analysis, an evidence-based method that elucidates the physical and psychological consequences associated with exposures to harm and loss during disasters and complex emergencies, was used to identify the psychological risk factors and potentially traumatic events experienced by conflict-displaced persons in Colombia, stratified across the phases of displacement. Trauma and loss are experienced differentially throughout the pathway of displacement. PMID:25135775

  1. Cutting forces in ultrasonically assisted drilling of carbon fibre-reinforced plastics

    Science.gov (United States)

    Makhdum, Farrukh; Jennings, Luke T.; Roy, Anish; Silberschmidt, Vadim V.

    2012-08-01

    Ultrasonically assisted drilling (UAD) is a non-traditional hybrid machining process, which combines features of conventional drilling and vibratory machining techniques to obtain remarkable improvements in machinability of advanced materials. The experiments are conducted on commercially available samples of a carbon fibre-reinforced plastic (CFRP) at a feed rate of 16 mm/min. In this study, a thrust force reduction in excess of 60% is observed in UAD when compared to conventional drilling (CD). Lower delamination was observed when compared to CD techniques. Optical microscopy revealed that the material is removed as a continuous chip in UAD whereas in case of CD we observe powdered dust. Light and scanning electron microscopy of CFRP chips obtained in drilling elucidate fundamental differences in the underlying machining processes in UAD of CFRP.

  2. Attenuated geophysical signatures associated with ongoing remediation efforts at Wurtsmith Air Force Base, Oscoda, Michigan

    Science.gov (United States)

    Che-Alota, V.; Atekwana, E. A.; Sauck, W. A.; Nolan, J. T.; Slater, L. D.

    2007-12-01

    Previous geophysical investigations (1996, 1997, 2003, and 2004) conducted at the decommissioned Wurtsmith Air Force Base former Fire Training Cell (FT-02) showed a clearly defined high conductivity anomaly associated with hydrocarbon contaminants in the vadose zone and ground water near the source area. The source of the geophysical anomalies was attributed to biogeochemical modifications of the contaminated zone resulting from intrinsic bioremediation. During these previous surveys, ground penetrating radar (GPR) data showed a zone of attenuated GPR reflections extending from the vadose zone to below the water table. Self potential data (SP) data defined a positive anomaly coincident with the hydrochemically defined plume, while electrical resistivity data showed anomalously high conductivity within the zone of impact. In 2007, another integrated geophysical study of the site was conducted. GPR, SP, electrical resistivity, and induced polarization surveys were conducted with expectations of achieving similar results as the past surveys. However, preliminary assessment of the data shows a marked decrease in electrical conductivity and SP response over the plume. GPR data still showed the attenuated signals, but the zone of attenuation was only observed below the water table. We attribute the attenuation of the observed geophysical anomalies to ongoing soil vapor extraction initiated in 2003. Significant removal of the contaminant mass by the vapor extraction system has altered the subsurface biogeochemical conditions and these changes were documented by the 2007 geophysical and geochemical data. The results of this study show that the attenuation of the contaminant plume is detectable with geophysical methods.

  3. Dry Machining Aeronautical Aluminum Alloy AA2024-T351: Analysis of Cutting Forces, Chip Segmentation and Built-Up Edge Formation

    Directory of Open Access Journals (Sweden)

    Badis Haddag

    2016-08-01

    Full Text Available In this paper, machining aeronautical aluminum alloy AA2024-T351 in dry conditions was investigated. Cutting forces, chip segmentation, and built-up edge formation were analyzed. Machining tests revealed that the chip formation process depends on cutting conditions and tool geometry. So continuous and segmented chips are generated. Under some cutting conditions, built-up edge formation occurs. A predictive machining theory, based on a finite elements method (FEM, was applied to reproduce and explain these phenomena. Thermomechanical behaviors of the work material and the tool-work material interface were considered. Results of the proposed modelling were compared to experimental data for a wide range of cutting speed. It was shown that the feed force is well reproduced by the ALE-FE (arbitrary lagrangian-eulerian finite element formulation and highly underestimated by the lagrangian finite element (LAG-FE one. While, the periodic localized shear band, leading to a chip segmentation, is well reproduced with the Lagrangian FE formulation. It was found that the chip segmentation can be correlated to the cutting force evolution using the defined chip segmentation intensity parameter. For the built-up edge (BUE phenomenon, it was shown that it depends on the contact/friction at the tool-chip interface, and this is possible to simulate by making the friction coefficient time-dependent.

  4. Effect of Cutting Parameters on Thrust Force and Surface Roughness in Drilling of Al-2219/B4C/Gr Metal Matrix Composites

    Science.gov (United States)

    Ravindranath, V. M.; Basavarajappa, G. S. Shiva Shankar S.; Suresh, R.

    2016-09-01

    In aluminium matrix composites, reinforcement of hard ceramic particle present inside the matrix which causes tool wear, high cutting forces and poor surface finish during machining. This paper focuses on effect of cutting parameters on thrust force, surface roughness and burr height during drilling of MMCs. In the present work, discuss the influence of spindle speed and feed rate on drilling the pure base alloy (Al-2219), mono composite (Al- 2219+8% B4C) and hybrid composite (Al-2219+8%B4C+3%Gr). The composites were fabricated using liquid metallurgy route. The drilling experiments were conducted by CNC machine with TiN coated HSS tool, M42 (Cobalt grade) and carbide tools at various spindle speeds and feed rates. The thrust force, surface roughness and burr height of the drilled hole were investigated in mono composite and hybrid composite containing graphite particles, the experimental results show that the feed rate has more influence on thrust force and surface roughness. Lesser thrust force and discontinuous chips were produced during machining of hybrid composites when compared with mono and base alloy during drilling process. It is due to solid lubricant property of graphite which reduces the lesser thrust force, burr height and lower surface roughness. When machining with Carbide tool at low feed and high speeds good surface finish was obtained compared to other two types of cutting tool materials.

  5. Cutting force model for high speed machining process; Modelo matematico para la prediccion del esfuerzo de corte en el mecanizado a alta velocidad

    Energy Technology Data Exchange (ETDEWEB)

    Haber, R. E.; Jimenez, J. E.; Jimenez, A.; Lopez-Coronado, J.

    2004-07-01

    This paper presents cutting force-based models able to describe a high speed machining process. The model considers the cutting force as output variable, essential for the physical processes that are taking place in high speed machining. Moreover, this paper shows the mathematical development to derive the integral-differential equations, and the algorithms implemented in MATLAB to predict the cutting force in real time MATLAB is a software tool for doing numerical computations with matrices and vectors. It can also display information graphically and includes many toolboxes for several research and applications areas. Two end mill shapes are considered (i. e. cylindrical and ball end mill) for real-time implementation of the developed algorithms. the developed models are validated in slot milling operations. The results corroborate the importance of the cutting force variable for predicting tool wear in high speed machining operations. The developed models are the starting point for future work related with vibration analysis, process stability and dimensional surface finish in high speed machining processes. (Author) 19 refs.

  6. Study of performance of high speed turning using the volumetric dimension coefficient of resultant cutting force; Estudio del rendimiento del torneado de alta velocidad utilizando el coeficiente de dimension volumetrica de la fuerza de corte resultante

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Gonzalez, L. W.; Perez-Rodriguez, R.; Zambrano-Robledo, P. C.; Siller-Carrillo, H. R.; Toscano-Reyes, H.

    2013-07-01

    This work deals with the experimental study of the resultant cutting force evolution of two coating carbide and a cermet inserts, during the dry turning of AISI 1045 steel with 400, 500 and 600 m/min cutting speeds. A new criterion for machinability study, the coefficient of volumetric dimension of cutting force, it is introduced. The investigation showed a better performance of cermet for moderate and intermediate cutting speeds, while at high cutting speed and final machining time, the three layers coated carbide achieved the best result. The factorial analysis of variance demonstrated a significant effect of machining time on the coefficient of volumetric dimension of resultant cutting force, while the material insert factor and their interaction, for intermediate cutting speed was just significant. (Author)

  7. Signature of the CERN GoldenBook at CERN by Peters Higgs British theoretical physicist - He worked on proposals to unify the weak and the electromagnetic forces into a single electroweak theory, The Boson of Higgs.

    CERN Multimedia

    Claudia Marcelloni

    2008-01-01

    Signature of the CERN GoldenBook at CERN by Peters Higgs British theoretical physicist - He worked on proposals to unify the weak and the electromagnetic forces into a single electroweak theory, The Boson of Higgs.

  8. Effect of type and percentage of reinforcement for optimization of the cutting force in turning of Aluminium matrix nanocomposites using response surface methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Priyadarshi, Devinder [DAV Institute of Engineering and Technology, Jalandhar (India); Sharma, Rajesh Kumar [Institute of Technology, Hamirpur (India)

    2016-03-15

    Aluminium matrix composites (AMCs) now hold a significant share of raw materials in many applications. It is of prime importance to study the machinability of such composites so as to enhance their applicability. Sufficient work has been done for studying the machining of AMCs with particle reinforcements of micron range. This paper presents the study of AMCs with particle reinforcement of under micron range i.e. nanoparticles. This paper brings out the results of an experimental investigation of type and weight percent of nanoparticles on the tangential cutting force during turning operation. SiC, Gr and SiC-Gr (in equal proportions) were used with Al-6061 alloy as the matrix phase. The results indicate that composites with SiC require greater cutting force followed by hybrid and then Gr. Increase in the weight percent also significantly affected the magnitude of cutting force. RSM was used first to design and analyze the experiments and then to optimize the turning process and obtain optimal conditions of weight and type of reinforcements for turning operation.

  9. Amputee locomotion: Frequency content of prosthetic vs. intact limb vertical ground reaction forces during running and the effects of filter cut-off frequency.

    Science.gov (United States)

    Kiernan, Dovin; Miller, Ross H; Baum, Brian S; Kwon, Hyun Joon; Shim, Jae Kun

    2017-07-26

    Compared to intact limbs, running-specific prostheses have high resonance non-biologic materials and lack active tissues to damp high frequencies. These differences may lead to ground reaction forces (GRFs) with high frequency content. If so, ubiquitously applying low-pass filters to prosthetic and intact limb GRFs may attenuate veridical high frequency content and mask important and ecologically valid data from prostheses. To explore differences in frequency content between prosthetic and intact limbs we divided signal power from transtibial unilateral amputees and controls running at 2.5, 3.0, and 3.5m/s into Low (25Hz) frequency bandwidths. Faster speeds tended to reduce the proportion of signal power in the Low bandwidth while increasing it in the High and Non-biologic bandwidths. Further, prostheses had lower proportions of signal power at the High frequency bandwidth but greater proportions at the Non-biologic bandwidth. To evaluate whether these differences in frequency content interact with filter cut-offs and alter results, we filtered GRFs with cut-offs from 1 to 100Hz and calculated vertical impact peak (VIP). Changing cut-off had inconsistent effects on VIP across speeds and limbs: Faster speeds had significantly larger changes in VIP per change in cut-off while, compared to controls, prosthetic limbs had significantly smaller changes in VIP per change in cut-off. These findings reveal differences in GRF frequency content between prosthetic and intact limbs and suggest that a cut-off frequency that is appropriate for one limb or speed may be inappropriate for another. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Institute of Geophysics, Planetary Physics, and Signatures

    Data.gov (United States)

    Federal Laboratory Consortium — The Institute of Geophysics, Planetary Physics, and Signatures at Los Alamos National Laboratory is committed to promoting and supporting high quality, cutting-edge...

  11. Orthogonal cutting forces in juvenile and mature Pinus taeda wood Forças de corte ortogonal na madeira juvenil e adulta de Pinus taeda

    Directory of Open Access Journals (Sweden)

    Raquel Gonçalves

    2005-08-01

    Full Text Available The distinct characteristics of juvenile and mature woods, which are observed particularly in softwoods, have an influence on processing due to their different mechanical resistance properties in relation to cutting operations. In the past, when most of the wood used industrially came from adult trees of natural forests, little importance was given to a distinction between different zones of the tree stem. At present, however, as the supply of mature trees with large diameters from native forests is constantly decreasing, the use of short-cycle trees has become a common practice, through the adoption of species that grow relatively fast, such as pines and eucalyptus. In both softwoods and hardwoods, juvenile wood cells are generally smaller and thinner than in mature wood, and this reflects on their density and mechanical resistance, which should have an effect on the cutting forces developed during processing. The main object of this research was to evaluate orthogonal cutting forces in juvenile and mature Pinus taeda woods. Cutting force magnitude differences were observed for those two regions of the trunk, with parallel cutting forces being 33.4% higher, on average, at the mature wood region for 90-0 cutting, and 12% higher for 90-90 cutting. This result is consistent with the distinct anatomical structures of the material, since the forces developed during machining depend directly upon its properties.As características distintas dos lenhos juvenil e adulto, existentes principalmente na formação das coníferas, influenciam na usinagem devido às diferentes propriedades de resistência mecânica ao corte. No passado, quando a maior parte da madeira utilizada industrialmente era proveniente de árvores adultas de florestas naturais, pouca importância era dada à diferenciação de zonas no tronco. Atualmente, no entanto, com o decréscimo constante do suprimento de árvores adultas de grandes diâmetros, provenientes de florestas nativas

  12. Drilling High Precision Holes in Ti6Al4V Using Rotary Ultrasonic Machining and Uncertainties Underlying Cutting Force, Tool Wear, and Production Inaccuracies.

    Science.gov (United States)

    Chowdhury, M A K; Sharif Ullah, A M M; Anwar, Saqib

    2017-09-12

    Ti6Al4V alloys are difficult-to-cut materials that have extensive applications in the automotive and aerospace industry. A great deal of effort has been made to develop and improve the machining operations of Ti6Al4V alloys. This paper presents an experimental study that systematically analyzes the effects of the machining conditions (ultrasonic power, feed rate, spindle speed, and tool diameter) on the performance parameters (cutting force, tool wear, overcut error, and cylindricity error), while drilling high precision holes on the workpiece made of Ti6Al4V alloys using rotary ultrasonic machining (RUM). Numerical results were obtained by conducting experiments following the design of an experiment procedure. The effects of the machining conditions on each performance parameter have been determined by constructing a set of possibility distributions (i.e., trapezoidal fuzzy numbers) from the experimental data. A possibility distribution is a probability-distribution-neural representation of uncertainty, and is effective in quantifying the uncertainty underlying physical quantities when there is a limited number of data points which is the case here. Lastly, the optimal machining conditions have been identified using these possibility distributions.

  13. Effects of Increasing Feed Rate on Tool Deterioration and Cutting Force during End Milling of 718Plus Superalloy Using Cemented Tungsten Carbide Tool

    Directory of Open Access Journals (Sweden)

    Nurul H. Razak

    2017-10-01

    Full Text Available Understanding how feed rate (ft affects tool deterioration during milling of Ni-based superalloys is practically important, but this understanding is currently insufficient. In the present study using a 718Plus Ni-based alloy and cemented tungsten carbide tool inserts, milling experiments were conducted with ft = 0.10 mm/tooth under either dry or wet (with coolant conditions. The results are compared to those based on using ft = 0.05 mm/tooth from previous studies. The milling force (F was monitored, the cutting tool edge was examined and the flank wear (VBmax was measured. As would be expected, an increase in ft increased F. It was found that F correlated well with VBmax for the high ft (0.1 mm/tooth experiments, as opposed to the previously observed poor F-VBmax relationship for the lower ft (0.05 mm/tooth value. This is explained, supported by detailed failure analysis of the cutting tool edges, by the deterioration mode to be dominantly edge chipping with a low occurrence of fracturing along the flank face when the high ft was used. This dominancy of the deterioration mode means that the tool edge and workpiece contact was consistent and thus resulted in a clear F-VBmax relationship. A clear F-VBmax relationship should then mean monitoring VBmax through monitoring F is possible.

  14. Force

    CERN Document Server

    Graybill, George

    2007-01-01

    Forces are at work all around us. Discover what a force is, and different kinds of forces that work on contact and at a distance. We use simple language and vocabulary to make this invisible world easy for students to ""see"" and understand. Examine how forces ""add up"" to create the total force on an object, and reinforce concepts and extend learning with sample problems.

  15. Determination of gas & liquid two-phase flow regime transitions in wellbore annulus by virtual mass force coefficient when gas cut

    Science.gov (United States)

    Qu, Junbo; Yan, Tie; Sun, Xiaofeng; Chen, Ye; Pan, Yi

    2017-10-01

    With the development of drilling technology to deeper stratum, overflowing especially gas cut occurs frequently, and then flow regime in wellbore annulus is from the original drilling fluid single-phase flow into gas & liquid two-phase flow. By using averaged two-fluid model equations and the basic principle of fluid mechanics to establish the continuity equations and momentum conservation equations of gas phase & liquid phase respectively. Relationship between pressure and density of gas & liquid was introduced to obtain hyperbolic equation, and get the expression of the dimensionless eigenvalue of the equation by using the characteristic line method, and analyze wellbore flow regime to get the critical gas content under different virtual mass force coefficients. Results show that the range of equation eigenvalues is getting smaller and smaller with the increase of gas content. When gas content reaches the critical point, the dimensionless eigenvalue of equation has no real solution, and the wellbore flow regime changed from bubble flow to bomb flow. When virtual mass force coefficients are 0.50, 0.60, 0.70 and 0.80 respectively, the critical gas contents are 0.32, 0.34, 0.37 and 0.39 respectively. The higher the coefficient of virtual mass force, the higher gas content in wellbore corresponding to the critical point of transition flow regime, which is in good agreement with previous experimental results. Therefore, it is possible to determine whether there is a real solution of the dimensionless eigenvalue of equation by virtual mass force coefficient and wellbore gas content, from which we can obtain the critical condition of wellbore flow regime transformation. It can provide theoretical support for the accurate judgment of the annular flow regime.

  16. Ultrasonic Cutting of Foods

    Science.gov (United States)

    Schneider, Yvonne; Zahn, Susann; Rohm, Harald

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

  17. DEEPWAVE Initial Investigation of Mesospheric Gravity Wave Signatures Generated by Variable Orographic Forcing Over Lauder Station (45°S). New Zealand

    Science.gov (United States)

    Criddle, N.; Taylor, M. J.; Pautet, P. D.; Zhao, Y.

    2014-12-01

    DEEPWAVE is a new international collaborative research program focused on identifying, characterizing, and predicting the generation and propagation of deeply propagating atmospheric gravity waves from the Earth's surface up to ̴100 km altitude and beyond. An extended series of coordinated airborne and ground-based measurements were recently conducted from New Zealand's South Island to investigate gravity wave forcing during the winter months when strong North-Westerly winds are known to generate gravity waves capable of penetrating well into the stratosphere. As part of this collaborative effort the Atmospheric Imaging Lab at Utah State University (USU) deployed and operated an Advanced Mesospheric Temperature Mapper (AMTM) at the National Institute for Water and Atmosphere (NIWA) Lauder research station, NZ (45°S 169°E). In the lee of the Southern Alps, Lauder is well positioned for measuring a broad spectrum of gravity waves launched from south island orography and from other meteorological sources. The AMTM is uniquely capable of mapping the wave-induced temperature perturbations to investigate the two-dimensional gravity wave field with high temporal ( ̴10 sec) and high temperature precision ( ̴1-2 K in 30 sec). High-quality infrared image measurements of the OH (3,1) band emission layer (altitude ̴ 87 km) were made nightly from May 31 to July 22, 2014. The DEEPWAVE program has been a resounding success and over 42 nights of data were obtained at Lauder with distinct mesospheric mountain wave signatures recorded there in OH intensity, and in temperatures for the first time. In this poster we provide a summary of the AMTM data set from Lauder, complemented by data from coincident airborne over-flights where appropriate, and we present initial results characterizing the mesopause gravity wave field under varying orographic forcings. We thank the NSF for sponsoring this research program.

  18. Performance Testing of Cutting Fluids

    DEFF Research Database (Denmark)

    Belluco, Walter

    The importance of cutting fluid performance testing has increased with documentation requirements of new cutting fluid formulations based on more sustainable products, as well as cutting with minimum quantity of lubrication and dry cutting. Two sub-problems have to be solved: i) which machining...... tests feature repeatability, reproducibility and sensitivity to cutting fluids, and ii) to what extent results of one test ensure relevance to a wider set of machining situations. The present work is aimed at assessing the range of validity of the different testing methods, investigating correlation...... within the whole range of operations, materials, cutting fluids, operating conditions, etc. Cutting fluid performance was evaluated in turning, drilling, reaming and tapping, and with respect to tool life, cutting forces, chip formation and product quality (dimensional accuracy and surface integrity...

  19. Application of response surface methodology for determining cutting ...

    Indian Academy of Sciences (India)

    by software Minitab (multiple linear regression and response surface methodology) in order to express the influence degree of the main cutting variables such as cutting speed, feed rate and depth of cut on cutting force components. These models would be helpful in selecting cutting variables for optimization of hard cutting ...

  20. Cutting edge

    CERN Multimedia

    McMullen, K

    1999-01-01

    A new collaboration has been set up between physicists at CERN and artists at the London Institute. The research programme called "Signatures of the Invisible' is aiming to hold exhibitions simultaneously in three European locations next year (1 pg)

  1. Optical Cutting Interruption Sensor for Fiber Lasers

    Directory of Open Access Journals (Sweden)

    Benedikt Adelmann

    2015-09-01

    Full Text Available We report on an optical sensor system attached to a 4 kW fiber laser cutting machine to detect cutting interruptions. The sensor records the thermal radiation from the process zone with a modified ring mirror and optical filter arrangement, which is placed between the cutting head and the collimator. The process radiation is sensed by a Si and InGaAs diode combination with the detected signals being digitalized with 20 kHz. To demonstrate the function of the sensor, signals arising during fusion cutting of 1 mm stainless steel and mild steel with and without cutting interruptions are evaluated and typical signatures derived. In the recorded signals the piercing process, the laser switch on and switch off point and waiting period are clearly resolved. To identify the cutting interruption, the signals of both Si and InGaAs diodes are high pass filtered and the signal fluctuation ranges being subsequently calculated. Introducing a correction factor, we identify that only in case of a cutting interruption the fluctuation range of the Si diode exceeds the InGaAs diode. This characteristic signature was successfully used to detect 80 cutting interruptions of 83 incomplete cuts (alpha error 3.6% and system recorded no cutting interruption from 110 faultless cuts (beta error of 0. This particularly high detection rate in combination with the easy integration of the sensor, highlight its potential for cutting interruption detection in industrial applications.

  2. Cutting assembly

    Science.gov (United States)

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

    1984-01-01

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

  3. Radiation signatures

    International Nuclear Information System (INIS)

    McGlynn, S.P.; Varma, M.N.

    1992-01-01

    A new concept for modelling radiation risk is proposed. This concept is based on the proposal that the spectrum of molecular lesions, which we dub ''the radiation signature'', can be used to identify the quality of the causal radiation. If the proposal concerning radiation signatures can be established then, in principle, both prospective and retrospective risk determination can be assessed on an individual basis. A major goal of biophysical modelling is to relate physical events such as ionization, excitation, etc. to the production of radiation carcinogenesis. A description of the physical events is provided by track structure. The track structure is determined by radiation quality, and it can be considered to be the ''physical signature'' of the radiation. Unfortunately, the uniqueness characteristics of this signature are dissipated in biological systems in ∼10 -9 s. Nonetheless, it is our contention that this physical disturbance of the biological system eventuates later, at ∼10 0 s, in molecular lesion spectra which also characterize the causal radiation. (author)

  4. Study of heat generation and cutting force according to minimization of grain size (500 nm to 180 nm) of WC ball endmill using FEM

    Science.gov (United States)

    Byeon, J. H.; Ahmed, F.; Ko, T. J.; lee, D. K.; Kim, J. S.

    2018-03-01

    As the industry develops, miniaturization and refinement of products are important issues. Precise machining is required for cutting, which is a typical method of machining a product. The factor determining the workability of the cutting process is the material of the tool. Tool materials include carbon tool steel, alloy tool steel, high-speed steel, cemented carbide, and ceramics. In the case of a carbide material, the smaller the particle size, the better the mechanical properties with higher hardness, strength and toughness. The specific heat, density, and thermal diffusivity are also changed through finer particle size of the material. In this study, finite element analysis was performed to investigate the change of heat generation and cutting power depending on the physical properties (specific heat, density, thermal diffusivity) of tool material. The thermal conductivity coefficient was obtained by measuring the thermal diffusivity, specific heat, and density of the material (180 nm) in which the particle size was finer and the particle material (0.05 μm) in the conventional size. The coefficient of thermal conductivity was calculated as 61.33 for 180nm class material and 46.13 for 0.05μm class material. As a result of finite element analysis using this value, the average temperature of exothermic heat of micronized particle material (180nm) was 532.75 °C and the temperature of existing material (0.05μm) was 572.75 °C. Cutting power was also compared but not significant. Therefore, if the thermal conductivity is increased through particle refinement, the surface power can be improved and the tool life can be prolonged by lowering the temperature generated in the tool during machining without giving a great influence to the cutting power.

  5. Cutting Cosmos

    DEFF Research Database (Denmark)

    Mikkelsen, Henrik Hvenegaard

    around which Bugkalot society revolves, but also a reflection on anthropological theory and writing. Focusing on the transgressive acts through which masculinity is performed, this book explores the idea of the cosmic cut, the ritual act that enables the Bugkalot man to momentarily hold still the chaotic......For the first time in over 30 years, a new ethnographic study emerges on the Bugkalot tribe, more widely known as the Ilongot of the northern Philippines. Exploring the notion of masculinity among the Bugkalot, Cutting Cosmos is not only an experimental, anthropological study of the paradoxes...

  6. Optical/Infrared Signatures for Space-Based Remote Sensing

    National Research Council Canada - National Science Library

    Picard, R. H; Dewan, E. M; Winick, J. R; O'Neil, R. R

    2007-01-01

    This report describes work carried out under the Air Force Research Laboratory's basic research task in optical remote-sensing signatures, entitled Optical / Infrared Signatures for Space-Based Remote Sensing...

  7. The size effect in metal cutting

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    The size effect in metal cutting. 877. Figure 3. Variation of shear stress on shear plane when cutting. SAE 1112 steel (after Backer et al. 1952). Horizontal and vertical forces were measured for a number of depths of cut(t)when machining the same-sized surface as in grinding. The shear stress on the shear plane (τ) was ...

  8. INFLUENCE OF POWER SPENT ON OVERCOMING CUTTING RESISTANCE FORCES ON ELECTRIC MOTOR POWER IN SYSTEM OF AUTOMATIC MACHINE CONTROL WITH NUMERICAL PROGRAMMED CONTROL

    Directory of Open Access Journals (Sweden)

    Shuxin Xu

    2009-01-01

    Full Text Available If a defect unexpectedly arises in the direction of supply while working a «free» curve being distinguished by a arbitrary curvature and small value twisting from the given ones then there will be worsening of cutting process that will lead to surface defects of the machined surface or tool break down. A method of wave analysis has been used for an experimental study of power in specific frequency bands and a minimum cutter damage has been obtained which with power on a drive motor makes it possible to control supply, restoring the condition of cutting. A technical novelty of automatic control method has been proposed according to instantaneous defect by means wave change on a drive motor. The problem of quantitative assessment of machined surface defects has been successfully solved in the paper.

  9. Using C-Band Dual-Polarization Radar Signatures to Improve Convective Wind Forecasting at Cape Canaveral Air Force Station and NASA Kennedy Space Center

    Science.gov (United States)

    Amiot, Corey G.; Carey, Lawrence D.; Roeder, William P.; McNamara, Todd M.; Blakeslee, Richard J.

    2017-01-01

    The United States Air Force's 45th Weather Squadron (45WS) is the organization responsible for monitoring atmospheric conditions at Cape Canaveral Air Force Station and NASA Kennedy Space Center (CCAFS/KSC) and issuing warnings for hazardous weather conditions when the need arises. One such warning is issued for convective wind events, for which lead times of 30 and 60 minutes are desired for events with peak wind gusts of 35 knots or greater (i.e., Threshold-1) and 50 knots or greater (i.e., Threshold-2), respectively (Roeder et al. 2014).

  10. eμ signal as heavy lepton signature at PEP

    International Nuclear Information System (INIS)

    Smith, J.

    1978-01-01

    A planned experiment to detect heavy leptons is described including the signature, cross sections, cuts to reduce the two-photon background to a tolerable level, and the computer program. The expected luminosity is also noted

  11. Material testing of copper by extrusion-cutting

    DEFF Research Database (Denmark)

    Segalina, F.; De Chiffre, Leonardo

    2017-01-01

    was developed and implemented on a CNC lathe. An investigation was carried out extrusion-cutting copper discs using high-speed-steel cutting tools at 100 m/min cutting speed. Flow stress values for copper under machining-relevant conditions were obtained from measurement of the extrusion-cutting force...

  12. New Modelling Strategies For Metal Cutting

    International Nuclear Information System (INIS)

    Rosa, Pedro A. R.; Martins, Paulo A. F.; Atkins, Anthony G.

    2007-01-01

    This paper draws from the 'plasticity and friction only' view of metal cutting to the presentation of new modelling strategies based on the interaction between finite elements and modern ductile fracture mechanics. The overall presentation is supported by specially designed orthogonal metal cutting experiments that were performed on Lead test specimens under laboratory-controlled conditions. Comparisons between theoretical predictions and experimental results comprise a wide range of topics such as material flow, cutting forces and specific cutting pressure. The paper demonstrates that while material flow and chip formation can be successfully modelled by traditional 'plasticity and friction only' analyses, the contribution of the fracture work involved in the formation of new surfaces is essential for obtaining good estimates of cutting forces and of the specific cutting pressure

  13. Experimental investigation of cutting parameters influence on ...

    Indian Academy of Sciences (India)

    This experimental investigation was conducted to determine the effects of cutting conditions on surface roughness and cutting forces in hard turning of X38CrMoV5-1. This steel was hardened at 50 HRC and machined with CBN tool. This is employed for the manufacture of helicopter rotor blades and forging dies. Combined ...

  14. Experimental investigation of cutting parameters influence on ...

    Indian Academy of Sciences (India)

    Abstract. This experimental investigation was conducted to determine the effects of cutting conditions on surface roughness and cutting forces in hard turning of. X38CrMoV5-1. This steel was hardened at 50 HRC and machined with CBN tool. This is employed for the manufacture of helicopter rotor blades and forging dies.

  15. Self Harm - Cutting

    Science.gov (United States)

    ... a sign that your child has thoughts of suicide. If you are concerned your child is cutting, learn the warning signs, methods of ... your child’s risk of cutting. While thoughts of suicide aren’t common with cutting, your child could accidentally cut deep enough or cut an ...

  16. Plasma arc cutting: speed and cut quality

    International Nuclear Information System (INIS)

    Nemchinsky, V A; Severance, W S

    2009-01-01

    When cutting metal with plasma arc cutting, the walls of the cut are narrower at the bottom than at the top. This lack of squareness increases as the cutting speed increases. A model of this phenomenon, affecting cut quality, is suggested. A thin liquid layer, which separates the plasma from the solid metal to be melted, plays a key role in the suggested model. This layer decreases heat transfer from the plasma to the solid metal; the decrease is more pronounced the higher the speed and the thicker the liquid metal layer. Since the layer is thicker at the bottom of the cut, the heat transfer effectiveness is lower at the bottom. The decrease in heat transfer effectiveness is compensated by the narrowness of the cut. The suggested model allows one to calculate the profile of the cut. The result of the calculations of the cutting speeds for plates of various thicknesses, at which the squareness of the cut is acceptable, agrees well with the speeds recommended by manufacturers. The second effect considered in the paper is the deflection of the plasma jet from the vertical at a high cutting speed. A qualitative explanation of this phenomenon is given. We believe the considerations of this paper are pertinent to other types of cutting with moving heat sources.

  17. Non-Poissonian photon statistics from macroscopic photon cutting materials.

    Science.gov (United States)

    de Jong, Mathijs; Meijerink, Andries; Rabouw, Freddy T

    2017-05-24

    In optical materials energy is usually extracted only from the lowest excited state, resulting in fundamental energy-efficiency limits such as the Shockley-Queisser limit for single-junction solar cells. Photon-cutting materials provide a way around such limits by absorbing high-energy photons and 'cutting' them into multiple low-energy excitations that can subsequently be extracted. The occurrence of photon cutting or quantum cutting has been demonstrated in a variety of materials, including semiconductor quantum dots, lanthanides and organic dyes. Here we show that photon cutting results in bunched photon emission on the timescale of the excited-state lifetime, even when observing a macroscopic number of optical centres. Our theoretical derivation matches well with experimental data on NaLaF 4 :Pr 3+ , a material that can cut deep-ultraviolet photons into two visible photons. This signature of photon cutting can be used to identify and characterize new photon-cutting materials unambiguously.

  18. Implementation Analysis of Cutting Tool Carbide with Cast Iron Material S45 C on Universal Lathe

    Science.gov (United States)

    Junaidi; hestukoro, Soni; yanie, Ahmad; Jumadi; Eddy

    2017-12-01

    Cutting tool is the tools lathe. Cutting process tool CARBIDE with Cast Iron Material Universal Lathe which is commonly found at Analysiscutting Process by some aspects numely Cutting force, Cutting Speed, Cutting Power, Cutting Indication Power, Temperature Zone 1 and Temperatur Zone 2. Purpose of this Study was to determine how big the cutting Speed, Cutting Power, electromotor Power,Temperatur Zone 1 and Temperatur Zone 2 that drives the chisel cutting CARBIDE in the Process of tur ning Cast Iron Material. Cutting force obtained from image analysis relationship between the recommended Component Cuting Force with plane of the cut and Cutting Speed obtained from image analysis of relationships between the recommended Cutting Speed Feed rate.

  19. Signature molecular descriptor : advanced applications.

    Energy Technology Data Exchange (ETDEWEB)

    Visco, Donald Patrick, Jr. (Tennessee Technological University, Cookeville, TN)

    2010-04-01

    In this work we report on the development of the Signature Molecular Descriptor (or Signature) for use in the solution of inverse design problems as well as in highthroughput screening applications. The ultimate goal of using Signature is to identify novel and non-intuitive chemical structures with optimal predicted properties for a given application. We demonstrate this in three studies: green solvent design, glucocorticoid receptor ligand design and the design of inhibitors for Factor XIa. In many areas of engineering, compounds are designed and/or modified in incremental ways which rely upon heuristics or institutional knowledge. Often multiple experiments are performed and the optimal compound is identified in this brute-force fashion. Perhaps a traditional chemical scaffold is identified and movement of a substituent group around a ring constitutes the whole of the design process. Also notably, a chemical being evaluated in one area might demonstrate properties very attractive in another area and serendipity was the mechanism for solution. In contrast to such approaches, computer-aided molecular design (CAMD) looks to encompass both experimental and heuristic-based knowledge into a strategy that will design a molecule on a computer to meet a given target. Depending on the algorithm employed, the molecule which is designed might be quite novel (re: no CAS registration number) and/or non-intuitive relative to what is known about the problem at hand. While CAMD is a fairly recent strategy (dating to the early 1980s), it contains a variety of bottlenecks and limitations which have prevented the technique from garnering more attention in the academic, governmental and industrial institutions. A main reason for this is how the molecules are described in the computer. This step can control how models are developed for the properties of interest on a given problem as well as how to go from an output of the algorithm to an actual chemical structure. This report

  20. Low Signature Tent Structures

    National Research Council Canada - National Science Library

    Cox, Randy

    1998-01-01

    .... Modeling shows that visual, near infrared, thermal, and radar signatures should be reduced when compared to other current tent designs. A brief treatise on the role of tent signatures and their results is included.

  1. Flexible Laser Metal Cutting

    DEFF Research Database (Denmark)

    Villumsen, Sigurd; Jørgensen, Steffen Nordahl; Kristiansen, Morten

    2014-01-01

    This paper describes a new flexible and fast approach to laser cutting called ROBOCUT. Combined with CAD/CAM technology, laser cutting of metal provides the flexibility to perform one-of-a-kind cutting and hereby realises mass production of customised products. Today’s laser cutting techniques...

  2. Multibeam Fibre Laser Cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    -laser cutting have until now limited its application in metal cutting. In this paper the first results of proof-of-principle studies applying a new approach (patent pending) for laser cutting with high brightness short wavelength lasers will be presented. In the approach, multi beam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from 2 single mode fibre lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W of single......The appearance of the high power high brilliance fibre laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating cutting laser, the CO2-laser. However, quality problems in fibre...

  3. Evaluation of Cutting Fluids in Multiple Reaming of Stainless Steel

    DEFF Research Database (Denmark)

    Belluco, Walter; Zeng, Z.; De Chiffre, Leonardo

    2001-01-01

    An investigation on the effect of different cutting fluids in reaming is presented. The performance of three water based cutting fluids and one cutting oil was compared to that of a reference water based commercial product by measurement of cutting forces, surface roughness and part accuracy. Three...... subsequent reaming operations were carried out on austenitic stainless steel using high-speed-steel and solid carbide tools. The tested fluids were all significantly different from the reference fluid in at least some of the tested conditions. Significant differences down to 2 percent in cutting forces and 6...

  4. Multibeam fiber laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Hansen, Klaus Schütt; Nielsen, Jakob Skov

    2009-01-01

    of single mode fiber laser power. Burr free cuts in 1 mm steel and aluminum and in 1 and 2 mm AISI 304 stainless steel is demonstrated over a wide range of cutting rates. The industrial realization of this approach is foreseen to be performed by either beam patterning by diffractive optical elements......The appearance of the high power high brilliance fiber laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating Cutting laser, the CO2 laser. However, quality problems in fiber...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from two single mode fiber lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W...

  5. Salt-Marsh Landscapes and the Signatures of Biogeomorphic Feedbacks

    Science.gov (United States)

    D'Alpaos, A.; Marani, M.

    2014-12-01

    Salt marshes are coastal ecosystems which play a large role in the bio-geomorphological evolution of intertidal areas. The dense stands of halophytic plants which populate salt-marsh systems largely contribute to govern their dynamics, influencing marsh hydrodynamics and sediment transport through enhanced flow resistance and settling, and direct particle capture by plant stems. In addition, plants are known to increase vertical accretion through direct organic accretion. Looking across the salt-marsh landscape can one see the signatures of feedbacks between landscape and biota? Field evidence and the results of biomorphodynamic models indeed show that the interplay between physical and biological processes generates some striking biological and morphological patterns at different scales. One such pattern, vegetation zonation, consists in a mosaic of vegetation patches, of approximately uniform composition, displaying sharp transitions in the presence of extremely small topographic gradients. Here we extend the model proposed by Marani et al. (2013) to a two-dimensional framework, furthermore including the effect of direct capture of sediment particles by plant stems. This allows us to account for the effect of the drainage density of tidal networks on the observed biogeomorphic patterns and to model the coupled evolution of marsh platforms and channel networks cutting through them. A number of different scenarios have been modelled to analyze the changes induced in bio-geomorphic patterns by plants with different characteristics, within marshes characterized by different drainage densities, or subjected to changing environmental forcing such as rates of relative sea level rise and sediment supply. Model results emphasize that zonation patterns are a signature of bio-geomorphic feedbacks with vegetation acting as a landscape constructor which feeds back on, directly alters, and contributes to shape tidal environments. In addition, model results show that

  6. Performances of cutting fluids in turning. Formulated oil - E

    DEFF Research Database (Denmark)

    Axinte, Dragos A.; Steffanato, Simone

    Tool life is a parameter closely connected to the lubricating effect of a cutting fluid. Long tool life in turning corresponds to good lubrication and a process with good lubrication is preferred, since it normally results in lower tool wear and better surface quality. Cutting forces are mainly...... important for understanding the mechanism of the cutting process itself and to perform in this way data about the influence of the cutting fluids....

  7. Investigation of tool engagement and cutting performance in machining a pocket

    Science.gov (United States)

    Adesta, E. Y. T.; Hamidon, R.; Riza, M.; Alrashidi, R. F. F. A.; Alazemi, A. F. F. S.

    2018-01-01

    This study investigates the variation of tool engagement for different profile of cutting. In addition, behavior of cutting force and cutting temperature for different tool engagements for machining a pocket also been explored. Initially, simple tool engagement models were developed for peripheral and slot cutting for different types of corner. Based on these models, the tool engagements for contour and zig zag tool path strategies for a rectangular shape pocket with dimension 80 mm x 60 mm were analyzed. Experiments were conducted to investigate the effect of tool engagements on cutting force and cutting temperature for the machining of a pocket of AISI H13 material. The cutting parameters used were 150m/min cutting speed, 0.05mm/tooth feed, and 0.1mm depth of cut. Based on the results obtained, the changes of cutting force and cutting temperature performance there exist a relationship between cutting force, cutting temperature and tool engagement. A higher cutting force and cutting temperature is obtained when the cutting tool goes through up milling and when the cutting tool makes a full engagement with the workpiece.

  8. Effect of cutting speed and feed in turning hardened stainless steel using coated carbide cutting tool under minimum quantity lubrication using castor oil

    Directory of Open Access Journals (Sweden)

    Mohamed Handawi Saad Elmunafi

    2015-08-01

    Full Text Available Minimum quantity lubrication is a technique to have the advantages that cutting fluids bring yet keeping their use at minimum. For the cutting fluids, inedible vegetable oils are potential for minimum quantity lubrication machining. Castor oil was selected in this study as the cutting fluid for turning of hardened stainless steel (hardness of 47–48 HRC. The hard turning was with minimum quantity lubrication (50 mL/h flow rate and 5 bar air pressure at various cutting speeds (100, 135, and 170 m/min and feeds (0.16, 0.20, and 0.24 mm/rev. The machining responses were tool life, surface roughness, and cutting forces. Design of experiments was applied to quantify the effects of cutting parameters to the machining responses. Empirical models for tool life, surface roughness, and cutting forces were developed within the range of cutting parameters selected. All machining responses are significantly influenced by the cutting speed and feed. Tool life is inversely proportional to cutting speed and feed. Surface roughness is inversely proportional to cutting speed yet is proportional to feed. Cutting forces are more influenced by feed than by cutting speed. A combination of low cutting speed and feed was the optimum cutting parameters to achieve long tool life, low surface roughness, and low cutting forces.

  9. Unconditionally Secure Quantum Signatures

    Directory of Open Access Journals (Sweden)

    Ryan Amiri

    2015-08-01

    Full Text Available Signature schemes, proposed in 1976 by Diffie and Hellman, have become ubiquitous across modern communications. They allow for the exchange of messages from one sender to multiple recipients, with the guarantees that messages cannot be forged or tampered with and that messages also can be forwarded from one recipient to another without compromising their validity. Signatures are different from, but no less important than encryption, which ensures the privacy of a message. Commonly used signature protocols—signatures based on the Rivest–Adleman–Shamir (RSA algorithm, the digital signature algorithm (DSA, and the elliptic curve digital signature algorithm (ECDSA—are only computationally secure, similar to public key encryption methods. In fact, since these rely on the difficulty of finding discrete logarithms or factoring large primes, it is known that they will become completely insecure with the emergence of quantum computers. We may therefore see a shift towards signature protocols that will remain secure even in a post-quantum world. Ideally, such schemes would provide unconditional or information-theoretic security. In this paper, we aim to provide an accessible and comprehensive review of existing unconditionally securesecure signature schemes for signing classical messages, with a focus on unconditionally secure quantum signature schemes.

  10. Radar Signature Calculation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...

  11. Welding and cutting

    International Nuclear Information System (INIS)

    Drews, P.; Schulze Frielinghaus, W.

    1978-01-01

    This is a survey, with 198 literature references, of the papers published in the fields of welding and cutting within the last three years. The subjects dealt with are: weldability of the materials - Welding methods - Thermal cutting - Shaping and calculation of welded joints - Environmental protection in welding and cutting. (orig.) [de

  12. Experimental investigation of cutting parameters influence on ...

    Indian Academy of Sciences (India)

    38, Part 3, June 2013, pp. 429–445. c Indian Academy of Sciences. Experimental investigation of cutting parameters influence on surface roughness and cutting forces in hard turning of X38CrMoV5-1 with CBN tool. H AOUICI1,2,∗. , M A YALLESE2, A BELBAH2, M F AMEUR1 and M ELBAH2. 1ENST-ex CT siège DG. SNVI ...

  13. Nanometric mechanical cutting of metallic glass investigated using atomistic simulation

    International Nuclear Information System (INIS)

    Wu, Cheng-Da; Fang, Te-Hua; Su, Jih-Kai

    2017-01-01

    Highlights: • A nanoscale chip with a shear plane of 135° is extruded by the tool. • Tangential force and normal force increase with increasing tool nose radius. • Resistance factor increases with increasing cutting depth and temperature. - Abstract: The effects of cutting depth, tool nose radius, and temperature on the cutting mechanism and mechanics of amorphous NiAl workpieces are studied using molecular dynamics simulations based on the second-moment approximation of the many-body tight-binding potential. These effects are investigated in terms of atomic trajectories and flow field, shear strain, cutting force, resistance factor, cutting ratio, and pile-up characteristics. The simulation results show that a nanoscale chip with a shear plane of 135° is extruded by the tool from a workpiece surface during the cutting process. The workpiece atoms underneath the tool flow upward due to the adhesion force and elastic recovery. The required tangential force and normal force increase with increasing cutting depth and tool nose radius; both forces also increase with decreasing temperature. The resistance factor increases with increasing cutting depth and temperature, and decreases with increasing tool nose radius.

  14. Experimental Investigation on Cutting Characteristics in Nanometric Plunge-Cutting of BK7 and Fused Silica Glasses.

    Science.gov (United States)

    An, Qinglong; Ming, Weiwei; Chen, Ming

    2015-03-27

    Ductile cutting are most widely used in fabricating high-quality optical glass components to achieve crack-free surfaces. For ultra-precision machining of brittle glass materials, critical undeformed chip thickness (CUCT) commonly plays a pivotal role in determining the transition point from ductile cutting to brittle cutting. In this research, cutting characteristics in nanometric cutting of BK7 and fused silica glasses, including machined surface morphology, surface roughness, cutting force and specific cutting energy, were investigated with nanometric plunge-cutting experiments. The same cutting speed of 300 mm/min was used in the experiments with single-crystal diamond tool. CUCT was determined according to the mentioned cutting characteristics. The results revealed that 320 nm was found as the CUCT in BK7 cutting and 50 nm was determined as the size effect of undeformed chip thickness. A high-quality machined surface could be obtained with the undeformed chip thickness between 50 and 320 nm at ductile cutting stage. Moreover, no CUCT was identified in fused silica cutting with the current cutting conditions, and brittle-fracture mechanism was confirmed as the predominant chip-separation mode throughout the nanometric cutting operation.

  15. Device for cutting protrusions

    Science.gov (United States)

    Bzorgi, Fariborz M [Knoxville, TN

    2011-07-05

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

  16. Digital Signature Management.

    Science.gov (United States)

    Hassler, Vesna; Biely, Helmut

    1999-01-01

    Describes the Digital Signature Project that was developed in Austria to establish an infrastructure for applying smart card-based digital signatures in banking and electronic-commerce applications. Discusses the need to conform to international standards, an international certification infrastructure, and security features for a public directory…

  17. Influence of temperature on the anisotropic cutting behaviour of single crystal silicon: A molecular dynamics simulation investigation

    OpenAIRE

    Chavoshi, Saeed Zare; Goel, Saurav; Luo, Xichun

    2016-01-01

    Using molecular dynamics (MD) simulation, this paper investigates anisotropic cutting behaviour of single crystal silicon in vacuum under a wide range of substrate temperatures (300 K, 500 K, 750 K, 850 K, 1173 K and 1500 K). Specific cutting energy, force ratio, stress in the cutting zone and cutting temperature were the indicators used to quantify the differences in the cutting behaviour of silicon. A key observation was that the specific cutting energy required to cut the (1 1 1) surface o...

  18. UV Signature Mutations †

    Science.gov (United States)

    2014-01-01

    Sequencing complete tumor genomes and exomes has sparked the cancer field's interest in mutation signatures for identifying the tumor's carcinogen. This review and meta-analysis discusses signatures and their proper use. We first distinguish between a mutagen's canonical mutations – deviations from a random distribution of base changes to create a pattern typical of that mutagen – and the subset of signature mutations, which are unique to that mutagen and permit inference backward from mutations to mutagen. To verify UV signature mutations, we assembled literature datasets on cells exposed to UVC, UVB, UVA, or solar simulator light (SSL) and tested canonical UV mutation features as criteria for clustering datasets. A confirmed UV signature was: ≥60% of mutations are C→T at a dipyrimidine site, with ≥5% CC→TT. Other canonical features such as a bias for mutations on the non-transcribed strand or at the 3' pyrimidine had limited application. The most robust classifier combined these features with criteria for the rarity of non-UV canonical mutations. In addition, several signatures proposed for specific UV wavelengths were limited to specific genes or species; non-signature mutations induced by UV may cause melanoma BRAF mutations; and the mutagen for sunlight-related skin neoplasms may vary between continents. PMID:25354245

  19. Machine Fault Signature Analysis

    Directory of Open Access Journals (Sweden)

    Pratesh Jayaswal

    2008-01-01

    Full Text Available The objective of this paper is to present recent developments in the field of machine fault signature analysis with particular regard to vibration analysis. The different types of faults that can be identified from the vibration signature analysis are, for example, gear fault, rolling contact bearing fault, journal bearing fault, flexible coupling faults, and electrical machine fault. It is not the intention of the authors to attempt to provide a detailed coverage of all the faults while detailed consideration is given to the subject of the rolling element bearing fault signature analysis.

  20. Threshold Signature Schemes Application

    Directory of Open Access Journals (Sweden)

    Anastasiya Victorovna Beresneva

    2015-10-01

    Full Text Available This work is devoted to an investigation of threshold signature schemes. The systematization of the threshold signature schemes was done, cryptographic constructions based on interpolation Lagrange polynomial, elliptic curves and bilinear pairings were examined. Different methods of generation and verification of threshold signatures were explored, the availability of practical usage of threshold schemes in mobile agents, Internet banking and e-currency was shown. The topics of further investigation were given and it could reduce a level of counterfeit electronic documents signed by a group of users.

  1. Underwater cutting techniques developments

    International Nuclear Information System (INIS)

    Bach, F.-W.

    1990-01-01

    The primary circuit structures of different nuclear powerplants are constructed out of stainless steels, ferritic steels, plated ferritic steels and alloys of aluminium. According to the level of the specific radiation of these structures, it is necessary for dismantling to work with remote controlled cutting techniques. The most successful way to protect the working crew against exposure of radiation is to operate underwater in different depths. The following thermal cutting processes are more or less developed to work under water: For ferritic steels only - flame cutting; For ferritic steels, stainless steels, cladded steels and aluminium alloys - oxy-arc-cutting, arc-waterjet-cutting with a consumable electrode, arc-saw-cutting, plasma-arc-cutting and plasma-arc-saw. The flame cutting is a burning process, all the other processes are melt-cutting processes. This paper explains the different techniques, giving a short introduction of the theory, a discussion of the possibilities with the advantages and disadvantages of these processes giving a view into the further research work in this interesting field. (author)

  2. Advanced Missile Signature Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Missile Signature Center (AMSC) is a national facility supporting the Missile Defense Agency (MDA) and other DoD programs and customers with analysis,...

  3. Cutting Class Harms Grades

    Science.gov (United States)

    Taylor, Lewis A., III

    2012-01-01

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

  4. Fundamentals of cutting.

    Science.gov (United States)

    Williams, J G; Patel, Y

    2016-06-06

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

  5. The effect of spending cuts on teen pregnancy

    OpenAIRE

    Paton, David; Wright, Liam

    2017-01-01

    In recent years, English local authorities have been forced to make significant cuts to devolved expenditure. In this paper, we examine the impact of reductions in local expenditure on one particular public health target: reducing rates of teen pregnancy. Contrary to predictions made at the time of the cuts, panel data estimates provide no evidence that areas which reduced expenditure the most have experienced relative increases in teenage pregnancy rates. Rather, expenditure cuts are associa...

  6. Advanced cutting techniques: laser and fissuration cutting

    International Nuclear Information System (INIS)

    Perrin, J.; Tanis, G.

    1984-01-01

    The aim of this study is to develop a new method for cutting metal components of nuclear power plants, which produces virtually no secondary waste. In this method, a controlled intergranular fissure is produced in a heated area of the component by the addition of a molten material which gives rise to the formation of brittle compounds. With the presence of molten metal, the material or alloys in which we have tension stresses can have a brittle intergranular failure. Generally the failure occurs in a defined temperature range. The tension stresses are created by the thermal gradient induced during the local heating. At the same time, the molten metal is added. Our work has been developed in two directions: Study on the maximum thickness (presently it is potentially possible to cut thick sheets up to 100 mm); dismantling of nuclear parts as tubes, cans, hot cell walls (we are on the beginning of the development in this field of work). (author)

  7. Cutting hospital costs without cutting staff.

    Science.gov (United States)

    Ortiz, John P

    2011-10-01

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

  8. Advanced cutting techniques: laser and fissuration cutting

    International Nuclear Information System (INIS)

    Migliorati, B.; Gay, P.

    1984-01-01

    Experimental tests have been performed using CO 2 laser with output power 1 to 15 kW to evaluate the effect of varying the following parameters: material (carbon steel Fe 42 C, stainless steel AISI 304, concrete), laser power, beam characteristics, work piece velocity, gas type and distribution on the laser interaction zone. In the case of concrete, drilling depths of 80 mm were obtained in a few seconds using a 10 kW laser beam. Moreover pieces of 160 mm were cut at 0.01 meters per minute. Results with carbon steel indicated maximum thicknesses of 110 mm, cut at 0.01 meters per minute with 10 kW, depths about 20% lower were obtained with the AISI 304 stainless steel. A parallel investigation was aimed at characterizing particulate emission during the laser cutting process. At the end of the research it was possible to elaborate a preliminary proposal concerning a laser based dismantling system for the application to a typical Nuclear Power Station. (author)

  9. Laser Cutting, Development Trends

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    1999-01-01

    In this paper a short review of the development trends in laser cutting will be given.The technology, which is the fastest expanding industrial production technology will develop in both its core market segment: Flat bed cutting of sheet metal, as it will expand in heavy industry and in cutting...... of 3-dimensional shapes.The CO2-laser will also in the near future be the dominating laser source in the market, although the new developments in ND-YAG-lasers opens for new possibilities for this laser type....

  10. Physical security of cut-and-cover underground facilities

    International Nuclear Information System (INIS)

    Morse, W.D.

    1998-01-01

    To aid designers, generic physical security objectives and design concepts for cut-and-cover underground facilities are presented. Specific aspects addressing overburdens, entryways, security doors, facility services, emergency egress, security response force, and human elements are discussed

  11. Research Results Of Stress-Strain State Of Cutting Tool When Aviation Materials Turning

    Science.gov (United States)

    Serebrennikova, A. G.; Nikolaeva, E. P.; Savilov, A. V.; Timofeev, S. A.; Pyatykh, A. S.

    2018-01-01

    Titanium alloys and stainless steels are hard-to-machine of all the machining types. Cutting edge state of turning tool after machining titanium and high-strength aluminium alloys and corrosion-resistant high-alloy steel has been studied. Cutting forces and chip contact arears with the rake surface of cutter has been measured. The relationship of cutting forces and residual stresses are shown. Cutting forces and residual stresses vs value of cutting tool rake angle relation were obtained. Measurements of residual stresses were performed by x-ray diffraction.

  12. Experimental testing of exchangeable cutting inserts cutting ability

    OpenAIRE

    Čep, Robert; Janásek, Adam; Čepová, Lenka; Petrů, Jana; Hlavatý, Ivo; Car, Zlatan; Hatala, Michal

    2013-01-01

    The article deals with experimental testing of the cutting ability of exchangeable cutting inserts. Eleven types of exchangeable cutting inserts from five different manufacturers were tested. The tested cutting inserts were of the same shape and were different especially in material and coating types. The main aim was both to select a suitable test for determination of the cutting ability of exchangeable cutting inserts and to design such testing procedure that could make it possible...

  13. Practical quantum digital signature

    Science.gov (United States)

    Yin, Hua-Lei; Fu, Yao; Chen, Zeng-Bing

    2016-03-01

    Guaranteeing nonrepudiation, unforgeability as well as transferability of a signature is one of the most vital safeguards in today's e-commerce era. Based on fundamental laws of quantum physics, quantum digital signature (QDS) aims to provide information-theoretic security for this cryptographic task. However, up to date, the previously proposed QDS protocols are impractical due to various challenging problems and most importantly, the requirement of authenticated (secure) quantum channels between participants. Here, we present the first quantum digital signature protocol that removes the assumption of authenticated quantum channels while remaining secure against the collective attacks. Besides, our QDS protocol can be practically implemented over more than 100 km under current mature technology as used in quantum key distribution.

  14. Short-cut math

    CERN Document Server

    Kelly, Gerard W

    1984-01-01

    Clear, concise compendium of about 150 time-saving math short-cuts features faster, easier ways to add, subtract, multiply, and divide. Each problem includes an explanation of the method. No special math ability needed.

  15. Tenderness charactherization of ostrich meat commercial cuts

    Directory of Open Access Journals (Sweden)

    Janaina Conte Hadlich

    2012-12-01

    Full Text Available The ostrich meat has become an interesting source of protein as well as being an alternative to red meat, because of its healthy fatty acid profile, with a high content of polyunsaturated fatty acids and low content of intramuscular fat, which arouses the interest of people who want a low animal fat diet. Ostrich meat is also appreciated by the tenderness, since it is one of the larger impact characteristics on the acceptance of a meat product for consumers. The aim of this study was to evaluate the tenderness of different ostrich meat commercial cuts and certificate that all studied cuts present tenderness acceptable by consumers. The laboratory tests were performed at the Laboratory of Biochemistry of Proteins (FMVZ, being measured shear force of seven commercial cuts of ostrich meat. The cuts were: internal thigh, external thigh, filet plan, filet out, filet small, rump and filet fan. The samples were boiled in water bath controlled by time and temperature. After chilling, fragments of 1.0 x 1.0 x 3.0 cm were removed from samples. Shear force measurements were performed using a mechanical Warner-Bratzler Shear Force equipment. The shear force means were: internal thigh (3.5 kg, external thigh (2.8 kg, filet plan (2.4 kg, filet out (1.6 kg, filet small (3.5 kg, rump (3.3 kg and filet fan (2.0 kg. All the commercial cuts evaluated had very low values of shear force, denoting meat extremely tender. The classification of meat tenderness is based on shear force values, being values below 4.6 kg considered meat with desirable tenderness. All ostrich meat commercial cuts analyzed had shear force values lower than 4.6 kg, being classified as meat of extreme tenderness. The results found in this work allow concluding that ostrich meat can be considered tender. These findings lead us to consider the ostrich meat as an interesting alternative to red meat, in relation to tenderness and healthy fatty acid profile, being favorable for people suffering from

  16. Laser cutting system

    Science.gov (United States)

    Dougherty, Thomas J

    2015-03-03

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

  17. Cutting and Self-Harm

    Science.gov (United States)

    ... Your feelings Feeling sad Cutting and self-harm Cutting and self-harm Self-harm, sometimes called self- ... There are many types of self-injury, and cutting is one type that you may have heard ...

  18. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-01-30

    This is the second quarterly progress report for Year 3 of the ACTS project. It includes a review of progress made in: (1) Flow Loop development and (2) research tasks during the period of time between Oct 1, 2001 and Dec. 31, 2001. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Collection System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  19. Signatures of Biogeomorphic Feedbacks in Salt-Marsh Systems

    Science.gov (United States)

    D'Alpaos, Andrea; Marani, Marco

    2015-04-01

    Salt-marsh ecosystems which play a large role in the bio-geomorphological evolution of intertidal areas. Dense stands of halophytic vegetations which populate salt marshes largely control the dynamics of these ecosystems influencing marsh hydrodynamics and sediment transport through enhanced flow resistance and settling, and direct particle capture by plant stems. Moreover, plants are also known to increase vertical accretion through direct organic accretion. Field evidence and the results of biomorphodynamic models indeed show that the interplay between physical and biological processes generates some striking biological and morphological patterns at different scales. One such pattern, vegetation zonation, consists in a mosaic of vegetation patches, of approximately uniform composition, displaying sharp transitions in the presence of extremely small topographic gradients. Here we develop a two-dimensional model which describes the mutual interaction and adjustment between tidal flows, sediment transport and morphology mediated by vegetation influence. The model allows us describe the coupled evolution of marsh platforms and channel networks cutting through them. A number of different scenarios were modelled to analyze the changes induced in bio-geomorphic patterns by plants with different characteristics, within marshes characterized by different drainage densities, or subjected to changing environmental forcing such as rates of relative sea level rise and sediment supply. Model results emphasize that zonation patterns are a signature of bio-geomorphic feedbacks with vegetation acting as a landscape constructor which feeds back on, directly alters, and contributes to shape tidal environments. In addition, model results show that biogeomorphic feedbacks critically affect the response and the resilience of salt-marsh landscapes to changes in the environmental forcing.

  20. Statistical clumped isotope signatures

    NARCIS (Netherlands)

    Röckmann, T.; Popa, M.E.; Krol, M.C.; Hofmann, M.E.G.

    2016-01-01

    High precision measurements of molecules containing more than one heavy isotope may provide novel constraints on element cycles in nature. These so-called clumped isotope signatures are reported relative to the random (stochastic) distribution of heavy isotopes over all available isotopocules of

  1. Signatures of the Invisible

    CERN Multimedia

    Strom, D

    2003-01-01

    On the Net it is possible to take a look at art from afar via Virtual Museums. One such exhibition was recently in the New York Museum of Modern Art's branch, PS1. Entitled 'Signatures of the Invisible' it was a collaborative effort between artists and physicists (1/2 page).

  2. Massively parallel signature sequencing.

    Science.gov (United States)

    Zhou, Daixing; Rao, Mahendra S; Walker, Roger; Khrebtukova, Irina; Haudenschild, Christian D; Miura, Takumi; Decola, Shannon; Vermaas, Eric; Moon, Keith; Vasicek, Thomas J

    2006-01-01

    Massively parallel signature sequencing is an ultra-high throughput sequencing technology. It can simultaneously sequence millions of sequence tags, and, therefore, is ideal for whole genome analysis. When applied to expression profiling, it reveals almost every transcript in the sample and provides its accurate expression level. This chapter describes the technology and its application in establishing stem cell transcriptome databases.

  3. The use of cutting temperature to evaluate the machinability of titanium alloys.

    Science.gov (United States)

    Kikuchi, Masafumi

    2009-02-01

    This study investigated the machinability of titanium, two commercial titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb) and free-cutting brass using the cutting temperature. The cutting temperature was estimated by measuring the thermal electromotive force of the tool-workpiece thermocouple during cutting. The thermoelectric power of each metal relative to the tool had previously been determined. The metals were slotted using a milling machine and carbide square end mills under four cutting conditions. The cutting temperatures of Ti-6Al-4V and Ti-6Al-7Nb were significantly higher than that of the titanium, while that of the free-cutting brass was lower. This result coincided with the relationship of the magnitude of the cutting forces measured in a previous study. For each metal, the cutting temperature became higher when the depth of cut or the cutting speed and feed increased. The increase in the cutting speed and feed was more influential on the value than the increase in the depth of cut when two cutting conditions with the same removal rates were compared. The results demonstrated that cutting temperature measurement can be utilized to develop a new material for dental CAD/CAM applications and to optimize the cutting conditions.

  4. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-09-30

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

  5. Stress Analysis of Marble Sawing Disc in Cutting Process

    Science.gov (United States)

    Ucun, Ismail; Colakoglu, Mehmet; Tasgetiren, Suleyman

    In this study, stresses in the marble cutting disc are investigated by finite element method. Normal and tangential forces in stress analysis are considered and critical stress regions are found. Depending on the chosen depth of cut, (i.e., 17.5, 40, 70 and 108 mm) these forces are applied in different values taken from an experimental study. In addition, the equivalent stress is also tried to determine under shock loading which occurs depending on working conditions and hardness of the marble. The analysis is carried out at four different cutting speeds. The results under the normal and shock loads are compared and the possible failure regions are studied.

  6. Research of a smart cutting tool based on MEMS strain gauge

    Science.gov (United States)

    Zhao, Y.; Zhao, Y. L.; Shao, YW; Hu, T. J.; Zhang, Q.; Ge, X. H.

    2018-03-01

    Cutting force is an important factor that affects machining accuracy, cutting vibration and tool wear. Machining condition monitoring by cutting force measurement is a key technology for intelligent manufacture. Current cutting force sensors exist problems of large volume, complex structure and poor compatibility in practical application, for these problems, a smart cutting tool is proposed in this paper for cutting force measurement. Commercial MEMS (Micro-Electro-Mechanical System) strain gauges with high sensitivity and small size are adopted as transducing element of the smart tool, and a structure optimized cutting tool is fabricated for MEMS strain gauge bonding. Static calibration results show that the developed smart cutting tool is able to measure cutting forces in both X and Y directions, and the cross-interference error is within 3%. Its general accuracy is 3.35% and 3.27% in X and Y directions, and sensitivity is 0.1 mV/N, which is very suitable for measuring small cutting forces in high speed and precision machining. The smart cutting tool is portable and reliable for practical application in CNC machine tool.

  7. Curved-Line Cutting Using a Flexible Circular Saw

    Science.gov (United States)

    Yamada, Yohei; Osumi, Nobuyuki; Takasugi, Akio; Sasahara, Hiroyuki

    We propose a flexible circular saw for high-speed cutting of curved lines in carbon fiber-reinforced plastic (CFRP). A conventional circular saw is appropriate for straight line cutting, but it cannot be applied to curved line cutting because of the interference between the saw body and the machined surface. To eliminate this problem, the flexible circular saw is deflected into a bowl shape by circular forced displacement, and the cross-section of the saw becomes a circular arc. A curved line can be cut by the bowl-like-deflection. The deflection shape is very important to realize the curved-line cutting without interference. We investigated the deflection of the flexible circular saw by a finite element method (FEM) analysis. Suitable slit shapes for the saw body are also proposed, based on the FEM results regarding stress in the saw body, the minimum radius of curvature, and the effects of cutting force and centrifugal force and eigenvalue. We also conducted a curved-line cutting test on a CFRP plate, and we found that the flexible circular saw can cut curved lines with high accuracy and high speed without interference between the saw body and the machined surface.

  8. Improved cutting performance in high power laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2003-01-01

    Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described.......Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described....

  9. Imaging, cutting, and collecting instrument and method

    Science.gov (United States)

    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.

  10. Modeling soft-tissue deformation prior to cutting for surgical simulation: finite element analysis and study of cutting parameters.

    Science.gov (United States)

    Chanthasopeephan, Teeranoot; Desai, Jaydev P; Lau, Alan C W

    2007-03-01

    This paper presents an experimental study to understand the localized soft-tissue deformation phase immediately preceding crack growth as observed during the cutting of soft tissue. Such understanding serves as a building block to enable realistic haptic display in simulation of soft tissue cutting for surgical training. Experiments were conducted for soft tissue cutting with a scalpel blade while monitoring the cutting forces and blade displacement for various cutting speeds and cutting angles. The measured force-displacement curves in all the experiments of scalpel cutting of pig liver sample having a natural bulge in thickness exhibited a characteristic pattern: repeating units formed by a segment of linear loading (deformation) followed by a segment of sudden unloading (localized crack extension in the tissue). During the deformation phase immediately preceding crack extension in the tissue, the deformation resistance of the soft tissue was characterized with the local effective modulus (LEM). By iteratively solving an inverse problem formulated with the experimental data and finite element models, this measure of effective deformation resistance was determined. Then computational experiments of model order reduction were conducted to seek the most computationally efficient model that still retained fidelity. Starting with a 3-D finite element model of the liver specimen, three levels of model order reduction were carried out with computational effort in the ratio of 1.000:0.103:0.038. We also conducted parametric studies to understand the effect of cutting speed and cutting angle on LEM. Results showed that for a given cutting speed, the deformation resistance decreased as the cutting angle was varied from 90 degrees to 45 degrees. For a given cutting angle, the deformation resistance decreased with increase in cutting speed.

  11. Underwater plasma arc cutting

    International Nuclear Information System (INIS)

    Leautier, R.; Pilot, G.

    1991-01-01

    This report describes the work done to develop underwater plasma arc cutting techniques, to characterise aerosols from cutting operations on radioactive and non-radioactive work-pieces, and to develop suitable ventilation and filtration techniques. The work has been carried out in the framework of a contract between CEA-CEN Cadarache and the Commission of European Communities. Furthermore, this work has been carried out in close cooperation with CEA-CEN Saclay mainly for secondary emissions and radioactive analysis. The contract started in May 1986 and was completed in December 1988 by a supplementary agreement. This report has been compiled from several progress reports submitted during the work period, contains the main findings of the work and encloses the results of comparative tests on plasma arc cutting

  12. Theoretical Models for Orthogonal Cutting

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”......This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”...

  13. Radial cutting torch

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, M.C.

    1997-01-08

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

  14. Laser hole cutting into bronze: Thermal stress analysis

    Science.gov (United States)

    Yilbas, B. S.; Ahktar, S. S.; Chatwin, C.

    2011-10-01

    Laser hole cutting in bronze is carried out and the thermal stress formed in the cutting section is examined using a finite element code. The cut geometry and microstructural changes in the cutting section are examined using optical microscope, scanning electron microscope (SEM), and energy dispersive spectroscopy (EDS). It is found that the high conductivity of bronze increases the cooling rates within the cutting section, which influences the thermal stress field in the cutting region. The residual stress predicted is in the order of 200 MPa within the vicinity of the hole circumference. The striation pattern at the kerf surface changes towards the hole exit, which is associated with the drag forces developed in this region.

  15. Mechanism of Transition-Metal Nanoparticle Catalytic Graphene Cutting.

    Science.gov (United States)

    Ma, Liang; Wang, Jinlan; Yip, Joanne; Ding, Feng

    2014-04-03

    Catalytic cutting by transition-metal (TM) particles is a promising method for the synthesizing of high-quality graphene quantum dots and nanoribbons with smooth edges. Experimentally, it is observed that the cutting always results in channels with zigzag (ZZ) or armchair (AC) edges. However, the driving force that is responsible for such a cutting behavior remains a puzzle. Here, by calculating the interfacial formation energies of the TM-graphene edges with ab initio method, we show that the surface of a catalyst particle tends to be aligned along either AC or ZZ direction of the graphene lattice, and thus the cutting of graphene is guided as such. The different cutting behaviors of various catalysts are well-explained based on the competition between TM-passivated graphene edges and the etching-agent-terminated ones. Furthermore, the kinetics of graphene catalytic cutting along ZZ and AC directions, respectively, are explored at the atomic level.

  16. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Troy Reed; Ergun Kuru

    2004-09-30

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

  17. Cutting work in thick section cryomicrotomy.

    Science.gov (United States)

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

    1977-09-01

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

  18. Cutting Cakes Carefully

    Science.gov (United States)

    Hill, Theodore P.; Morrison, Kent E.

    2010-01-01

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

  19. Cuts, Scratches, and Scrapes

    Science.gov (United States)

    ... Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Cuts, Scratches, and ... Infection Signs of Infection Print en español Cortes, rasguños ...

  20. Petrographic drill cutting analysis

    Energy Technology Data Exchange (ETDEWEB)

    Thom, R. [Core Laboratories Canada Ltd., Calgary, AB (Canada)

    1999-11-01

    Some of the diagnostic tools which are available to determine valuable reservoir rock information from drill cuttings were described. For example, valuable information can be obtained from drill cuttings and petrographic thin sections regarding mineralogy, facies, pore systems, reservoir quality and fluid sensitivity. This paper described the best ways to pick representative drill cuttings from vials. Colour and texture are among the most important determining factors. New guidelines from the Alberta Energy and Utilities Board have made it possible to obtain thin sections from drill cuttings from a competitor`s wells. Up to 12 chips from each vial can be removed for thin section scanning electron microscopy (SEM) analysis. X-ray diffraction (XRD) analysis of drill chips is not recommended because it is usually not possible to obtain enough sample material. Another powerful tool to investigate and characterize pore systems is the Mercury Injection Capillary Pressure technique. This technique makes it possible to characterize the pore system and to determine pore throat size distribution, permeability/porosity, producible reserves, capillary pressure, effective versus non-effective porosity, irreducible water saturation, and height above free water. The most reliable and valuable information is obtained from sandstone and carbonate aggregate chips in which the pore system is preserved. It was also noted that core porosity can be empirically derived if a trend line is constructed using sections prepared from an equivalent cored zone. Permeability can be derived in much the same way. 9 figs.

  1. Simultaneous Cake Cutting

    DEFF Research Database (Denmark)

    Balkanski, Eric; Branzei, Simina; Kurokawa, David

    2014-01-01

    We introduce the simultaneous model for cake cutting (the fair allocation of a divisible good), in which agents simultaneously send messages containing a sketch of their preferences over the cake. We show that this model enables the computation of divisions that satisfy proportionality — a popular...

  2. Core Cutting Test with Vertical Rock Cutting Rig (VRCR)

    Science.gov (United States)

    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.

  3. A simple but highly effective approach to evaluate the prognostic performance of gene expression signatures.

    Directory of Open Access Journals (Sweden)

    Maud H W Starmans

    Full Text Available BACKGROUND: Highly parallel analysis of gene expression has recently been used to identify gene sets or 'signatures' to improve patient diagnosis and risk stratification. Once a signature is generated, traditional statistical testing is used to evaluate its prognostic performance. However, due to the dimensionality of microarrays, this can lead to false interpretation of these signatures. PRINCIPAL FINDINGS: A method was developed to test batches of a user-specified number of randomly chosen signatures in patient microarray datasets. The percentage of random generated signatures yielding prognostic value was assessed using ROC analysis by calculating the area under the curve (AUC in six public available cancer patient microarray datasets. We found that a signature consisting of randomly selected genes has an average 10% chance of reaching significance when assessed in a single dataset, but can range from 1% to ∼40% depending on the dataset in question. Increasing the number of validation datasets markedly reduces this number. CONCLUSIONS: We have shown that the use of an arbitrary cut-off value for evaluation of signature significance is not suitable for this type of research, but should be defined for each dataset separately. Our method can be used to establish and evaluate signature performance of any derived gene signature in a dataset by comparing its performance to thousands of randomly generated signatures. It will be of most interest for cases where few data are available and testing in multiple datasets is limited.

  4. Cutting to the chase

    International Nuclear Information System (INIS)

    Snieckus, D.

    2001-01-01

    This article reports on the development of the cost effective abrasive cutting Sabre system which came as a result of UWG's work on the decommissioning of the Phillips' Maureen wells and adds to UWG's 'total severance solution' tools. The advantages of the system are highlighted and include the ability to operate from a platform or diving support vessel, to cut internal cases, and to eliminate the use of environmentally damaging explosives and the need to operate from a rig. The new Mark II version of the Sabre designed to work at greater depths of water, the range of the severance tools, UWG's well abandonment hole assembly system, and its aim to enter the Gulf of Mexico market are discussed. Details are given of the decommissioning of the Schwedeneck-See platforms in Kiel Bay off Germany and the Phillips' UK decommissioning plans for the Maureen platform

  5. Signatures of topological superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yang

    2017-07-19

    The prediction and experimental discovery of topological insulators brought the importance of topology in condensed matter physics into the limelight. Topology hence acts as a new dimension along which more and more new states of matter start to emerge. One of these topological states of matter, namely topological superconductors, comes into the focus because of their gapless excitations. These gapless excitations, especially in one dimensional topological superconductors, are Majorana zero modes localized at the ends of the superconductor and exhibit exotic nonabelian statistics, which can be potentially applied to fault-tolerant quantum computation. Given their highly interesting physical properties and potential applications to quantum computation, both theorists and experimentalists spend great efforts to realize topological supercondoctors and to detect Majoranas. In two projects within this thesis, we investigate the properties of Majorana zero modes in realistic materials which are absent in simple theoretical models. We find that the superconducting proximity effect, an essential ingredient in all existing platforms for topological superconductors, plays a significant role in determining the localization property of the Majoranas. Strong proximity coupling between the normal system and the superconducting substrate can lead to strongly localized Majoranas, which can explain the observation in a recent experiment. Motivated by experiments in Molenkamp's group, we also look at realistic quantum spin Hall Josephson junctions, in which charge puddles acting as magnetic impurities are coupled to the helical edge states. We find that with this setup, the junction generically realizes an exotic 8π periodic Josephson effect, which is absent in a pristine Josephson junction. In another two projects, we propose more pronounced signatures of Majoranas that are accessible with current experimental techniques. The first one is a transport measurement, which uses

  6. Signature CERN-URSS

    CERN Document Server

    Jentschke,W

    1975-01-01

    Le DG W.Jentschke souhaite la bienvenue à l'assemblée et aux invités pour la signature du protocole entre le Cern et l'URSS qui est un événement important. C'est en 1955 que 55 visiteurs soviétiques ont visité le Cern pour la première fois. Le premier DG au Cern, F.Bloch, et Mons.Amaldi sont aussi présents. Tandis que le discours anglais de W.Jentschke est traduit en russe, le discours russe de Mons.Morozov est traduit en anglais.

  7. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-07-30

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

  8. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-30

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

  9. Vortex cutting in superconductors

    Science.gov (United States)

    Vlasko-Vlasov, Vitalii K.; Koshelev, Alexei E.; Glatz, Andreas; Welp, Ulrich; Kwok, Wai-K.

    2015-03-01

    Unlike illusive magnetic field lines in vacuum, magnetic vortices in superconductors are real physical strings, which interact with the sample surface, crystal structure defects, and with each other. We address the complex and poorly understood process of vortex cutting via a comprehensive set of magneto-optic experiments which allow us to visualize vortex patterns at magnetization of a nearly twin-free YBCO crystal by crossing magnetic fields of different orientations. We observe a pronounced anisotropy in the flux dynamics under crossing fields and the filamentation of induced supercurrents associated with the staircase vortex structure expected in layered cuprates, flux cutting effects, and angular vortex instabilities predicted for anisotropic superconductors. At some field angles, we find formation of the vortex domains following a type-I phase transition in the vortex state accompanied by an abrupt change in the vortex orientation. To clarify the vortex cutting scenario we performed time-dependent Ginzburg-Landau simulations, which confirmed formation of sharp vortex fronts observed in the experiment and revealed a left-handed helical instability responsible for the rotation of vortices. This work was supported by the U.S. Department of Energy, Office of Science, Materials Sciences and Engineering Division.

  10. Effect of cutting parameters on machinability characteristics in milling of magnesium alloy with carbide tool

    Directory of Open Access Journals (Sweden)

    Kaining Shi

    2016-01-01

    Full Text Available Magnesium alloy has attracted more attentions due to its excellent mechanical properties. However, in process of dry cutting operation, many problems restrict its further development. In this article, the effect of cutting parameters on machinabilities of magnesium alloy is explored under dry milling condition. This research is an attempt to investigate the impact of cutting speed at multiple feed rates on cutting force and surface roughness, while a statistical analysis is adopted to determine the influential intensities accurately. The results showed that cutting force is affected by the positively constant intensity from feed rate and the increasingly negative intensity from cutting speed. In contrast, surface roughness is determined by the gradually increasing negative tendency from feed rate and the positive effect with constant intensity from cutting speed. Within the range of the experiments, feed rate is the leading contribution for cutting force while the cutting speed is the dominant factor for surface roughness according to the absolute intensity values. Meanwhile, the trends of influencing intensities between cutting force and surface roughness are opposite. Besides, it is also found that in milling magnesium alloy, chip morphology is highly sensitive to cutting speed while the chip quality mainly depends on feed rate.

  11. Remote Laser Cutting of CFRP: Improvements in the Cut Surface

    Science.gov (United States)

    Stock, Johannes; Zaeh, Michael F.; Conrad, Markus

    In the automotive industry carbon fibre reinforced plastics (CFRP) are considered as a future key material to reduce the weight of the vehicle. Therefore, capable production techniques are required to process this material in mass industry. E.g., state of the art methods for cutting are limited by the high tool wear or the feasible feed rate. Laser cutting processes are still under investigation. This paper presents detailed new studies on remote laser cutting of CFRP focusing on the influence of the material properties and the quality of the cut surface. By adding light absorbing soot particles to the resin of the matrix, the cutting process is improved and fewer defects emerge.

  12. Electronic Signature (eSig)

    Data.gov (United States)

    Department of Veterans Affairs — Beginning with the Government Paperwork Elimination Act of 1998 (GPEA), the Federal government has encouraged the use of electronic / digital signatures to enable...

  13. Expressiveness considerations of XML signatures

    DEFF Research Database (Denmark)

    Jensen, Meiko; Meyer, Christopher

    2011-01-01

    XML Signatures are used to protect XML-based Web Service communication against a broad range of attacks related to man-in-the-middle scenarios. However, due to the complexity of the Web Services specification landscape, the task of applying XML Signatures in a robust and reliable manner becomes...... more and more challenging. In this paper, we investigate this issue, describing how an attacker can still interfere with Web Services communication even in the presence of XML Signatures. Additionally, we discuss the interrelation of XML Signatures and XML Encryption, focussing on their security...

  14. Electronic Warfare Signature Measurement Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Electronic Warfare Signature Measurement Facility contains specialized mobile spectral, radiometric, and imaging measurement systems to characterize ultraviolet,...

  15. Toolset for evaluating infrared countermeasures and signature reduction for ships

    NARCIS (Netherlands)

    Schleijpen, H.M.A.

    2010-01-01

    The protection of ships against infrared guided missiles is a concern for modern naval forces. The vulnerability of ships can be reduced by applying countermeasures such as infrared decoys and infrared signature reduction. This paper presents a set of simulation tools which can be used for assessing

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Xueyi Li

    2013-01-01

    Full Text Available 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.

  18. Photochemical cutting of fabrics

    Science.gov (United States)

    Piltch, Martin S.

    1994-01-01

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

  19. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-07-31

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

  20. Cutting the Cord-2

    Science.gov (United States)

    2004-01-01

    This animation shows the view from the rear hazard avoidance cameras on the Mars Exploration Rover Spirit as the rover turns 45 degrees clockwise. This maneuver is the first step in a 3-point turn that will rotate the rover 115 degrees to face west. The rover must make this turn before rolling off the lander because airbags are blocking it from exiting from the front lander petal. Before this crucial turn took place, engineers instructed the rover to cut the final cord linking it to the lander. The turn took around 30 minutes to complete.

  1. Cutting the Cord

    Science.gov (United States)

    2004-01-01

    This animation shows the view from the front hazard avoidance cameras on the Mars Exploration Rover Spirit as the rover turns 45 degrees clockwise. This maneuver is the first step in a 3-point turn that will rotate the rover 115 degrees to face west. The rover must make this turn before rolling off the lander because airbags are blocking it from exiting off the front lander petal. Before this crucial turn could take place, engineers instructed the rover to cut the final cord linking it to the lander. The turn took around 30 minutes to complete.

  2. Can You Cut It?

    DEFF Research Database (Denmark)

    Kjær, Tina; Lillelund, Christoffer Bredo; Moth-Poulsen, Mie

    2017-01-01

    The advent of affordable virtual reality (VR) displays and 360◦ video cameras has sparked an interest in bringing cinematic experiences from the screen and into VR. However, it remains uncertain whether traditional approaches to filmmaking can be directly applied to cinematic VR. Historically......’ sense of disorientation and their ability to follow the story, during exposure to fictional 360◦ films experienced using a head-mounted display. The results revealed no effects of increased cut frequency which leads us to conclude that editing need not pose a problem in relation to cinematic VR, as long...

  3. Characteristics of elliptical vibration cutting in micro-V grooving with variations in the elliptical cutting locus and excitation frequency

    International Nuclear Information System (INIS)

    Kim, Gi Dae; Loh, Byoung Gook

    2008-01-01

    The characteristics of elliptical vibration cutting (EVC) in micro-V grooving in connection with variations of the elliptical cutting locus and the excitation frequency have been investigated with a cutting device consisting of orthogonally connected dual piezoelectric actuators. The elliptical cutting locus was modulated by changing the magnitude and phase difference of harmonic voltages supplied to the piezoelectric actuators, and the maximum excitation frequency used for EVC was 19 kHz. It was found that cyclic breaking of the contact between the tool and the workpiece is a pre-requisite for the merits of the EVC process to be realized. An index termed non-contact index (NCI) involving the vibration amplitude of the elliptical locus, the feed speed and the excitation frequency was defined to determine the existence of cyclic breaking of the contact under a given EVC condition. The surface roughness in the feed direction showed a tendency to increase with the vibration amplitude in the thrust direction and the square of the feed speed, and to decrease with the square of the vibration amplitude in the cutting direction and the square of the excitation frequency. The variation in the cutting resistance was in good agreement with the CR trend curve representing the contact ratio between the tool and the workpiece in EVC; in the EVC process involving breaking of the contact, marked decrease in the cutting force occurred at higher values of CR at which either slight increase in the excitation frequency or in the vibration amplitude results in significant decrease in the cutting force. Reduction in the cutting force preferably contributed to the improvement of machining quality of the micro features by inhibiting burr formation

  4. Multisensors signature prediction workbench

    Science.gov (United States)

    Latger, Jean; Cathala, Thierry

    2015-10-01

    Guidance of weapon systems relies on sensors to analyze targets signature. Defense weapon systems also need to detect then identify threats also using sensors. The sensors performance is very dependent on conditions e.g. time of day, atmospheric propagation, background ... Visible camera are very efficient for diurnal fine weather conditions, long wave infrared sensors for night vision, radar systems very efficient for seeing through atmosphere and/or foliage ... Besides, multi sensors systems, combining several collocated sensors with associated algorithms of fusion, provide better efficiency (typically for Enhanced Vision Systems). But these sophisticated systems are all the more difficult to conceive, assess and qualify. In that frame, multi sensors simulation is highly required. This paper focuses on multi sensors simulation tools. A first part makes a state of the Art of such simulation workbenches with a special focus on SE-Workbench. SEWorkbench is described with regards to infrared/EO sensors, millimeter waves sensors, active EO sensors and GNSS sensors. Then a general overview of simulation of targets and backgrounds signature objectives is presented, depending on the type of simulation required (parametric studies, open loop simulation, closed loop simulation, hybridization of SW simulation and HW ...). After the objective review, the paper presents some basic requirements for simulation implementation such as the deterministic behavior of simulation, mandatory to repeat it many times for parametric studies... Several technical topics are then discussed, such as the rendering technique (ray tracing vs. rasterization), the implementation (CPU vs. GP GPU) and the tradeoff between physical accuracy and performance of computation. Examples of results using SE-Workbench are showed and commented.

  5. Signatures de l'invisible

    CERN Multimedia

    CERN Press Office. Geneva

    2000-01-01

    "Signatures of the Invisible" is an unique collaboration between contemporary artists and contemporary physicists which has the potential to help redefine the relationship between science and art. "Signatures of the Invisible" is jointly organised by the London Institute - the world's largest college of art and design and CERN*, the world's leading particle physics laboratory. 12 leading visual artists:

  6. CO2 laser cutting

    CERN Document Server

    Powell, John

    1998-01-01

    The laser has given manufacturing industry a new tool. When the laser beam is focused it can generate one of the world's most intense energy sources, more intense than flames and arcs, though similar to an electron beam. In fact the intensity is such that it can vaporise most known materials. The laser material processing industry has been growing swiftly as the quality, speed and new manufacturing possibilities become better understood. In the fore of these new technologies is the process of laser cutting. Laser cutting leads because it is a direct process substitu­ tion and the laser can usually do the job with greater flexibility, speed and quality than its competitors. However, to achieve these high speeds with high quality con­ siderable know how and experience is required. This information is usually carefully guarded by the businesses concerned and has to be gained by hard experience and technical understanding. Yet in this book John Powell explains in lucid and almost non­ technical language many o...

  7. Leptogenesis: The other cuts

    International Nuclear Information System (INIS)

    Garbrecht, Bjoern

    2011-01-01

    For standard leptogenesis from the decay of singlet right-handed neutrinos, we derive source terms for the lepton asymmetry that are present in a finite density background but absent in the vacuum. These arise from cuts through the vertex correction to the decay asymmetry, where in the loop either the Higgs boson and the right-handed neutrino or the left-handed lepton and the right-handed neutrino are simultaneously on-shell. We evaluate the source terms numerically and use them to calculate the lepton asymmetry for illustrative points in parameter space, where we consider only two right-handed neutrinos for simplicity. Compared to calculations where only the standard cut through the propagators of left-handed lepton and Higgs boson is included, sizable corrections arise when the masses of the right-handed neutrinos are of the same order, but the new sources are found to be most relevant when the decaying right-handed neutrino is heavier than the one in the loop. In that situation, they can yield the dominant contribution to the lepton asymmetry.

  8. Researches regarding cutting tool condition monitoring

    Directory of Open Access Journals (Sweden)

    Inţă Marinela

    2017-01-01

    Full Text Available The paper main purpose is monitoring of tool wear in metal cutting using neural networks due to their ability of learning and adapting their self, based on experiments. Monitoring the cutting process is difficult to perform on-line because of the complexity of tool wear process, which is the most important parameter that defines the tool state at a certain moment. Most of the researches appraise the tool wear by indirect factors such as forces, consumed power, vibrations or the surface quality. In this case, it is important to combine many factors for increasing the accuracy of tool wear prediction and establish the admissible size of wear. For this, paper both the theoretical data obtained from FEM analyze and experimental ones are used and compared in order to appreciate the reliability of the results.

  9. Cutting the cornea with a waterjet keratome.

    Science.gov (United States)

    Lipshitz, I; Bass, R; Loewenstein, A

    1996-01-01

    Waterjet cutting is an advanced technology. It consists of a cutting tool that uses a very thin stream of ultra-high-pressure water forced at high velocity through a very small nozzle, creating a very sharp knife. We report on the first experimental use of waterjet technology to reshape the cornea. The system was used in vitro on 10 bovine eyes, and in vivo on 10 albino rabbit eyes. Using the waterjet keratome (Lipshitz-Bass knife, LBK) lamellar corneal incisions were performed. Histological examinations were performed. A waterjet stream was found to be capable of incising corneas at relatively low energy levels (4000 PSI). Good surface quality could be obtained, and there was no collateral damage to the remaining portion of the cornea, lens, or retina. In the in vivo experiments, the epithelium healed within 48 hours. These preliminary experiments suggest that waterjet technology can be an effective instrument for reshaping the cornea.

  10. Optimizing cutting conditions on sustainable machining of aluminum alloy to minimize power consumption

    Science.gov (United States)

    Nur, Rusdi; Suyuti, Muhammad Arsyad; Susanto, Tri Agus

    2017-06-01

    Aluminum is widely utilized in the industrial sector. There are several advantages of aluminum, i.e. good flexibility and formability, high corrosion resistance and electrical conductivity, and high heat. Despite of these characteristics, however, pure aluminum is rarely used because of its lacks of strength. Thus, most of the aluminum used in the industrial sectors was in the form of alloy form. Sustainable machining can be considered to link with the transformation of input materials and energy/power demand into finished goods. Machining processes are responsible for environmental effects accepting to their power consumption. The cutting conditions have been optimized to minimize the cutting power, which is the power consumed for cutting. This paper presents an experimental study of sustainable machining of Al-11%Si base alloy that was operated without any cooling system to assess the capacity in reducing power consumption. The cutting force was measured and the cutting power was calculated. Both of cutting force and cutting power were analyzed and modeled by using the central composite design (CCD). The result of this study indicated that the cutting speed has an effect on machining performance and that optimum cutting conditions have to be determined, while sustainable machining can be followed in terms of minimizing power consumption and cutting force. The model developed from this study can be used for evaluation process and optimization to determine optimal cutting conditions for the performance of the whole process.

  11. Study on optimal surface property of WC-Co cutting tool for aluminium alloy cutting

    International Nuclear Information System (INIS)

    Nizar, Mohd; Arimatsu, Naoya; Kawamitsu, Hiroshi; Takai, Kazuteru; Fukumoto, Masahiro

    2016-01-01

    The light weight property as well as high corrosion resistance of aluminium alloy has increased their demand especially in automobile industries. Aluminium alloy as a matter of fact has a low melting point and high ductility that severely adhere to the cutting tool surface and cause deterioration of chip evacuation. This problem often resulting in tools breakage. In this paper, in order to impart functions of anti-adhesion, we propose a technique by controlling the grinding marks micro texture on the tool surface by using the blast polishing treatment without any coating technologies. The results show that the tool which underwent polishing treatment reduces the cutting force as well as the aluminium adherence during the initial cutting process, and become worst as the process cutting continues. These results indicate that grinding mark texture improves the anti-adhesion by reducing the contact area during cutting and provide storage for the lubricant. In addition, too much polishing on the tool surface may remove these textures and resultantly worsen the tool performance. (paper)

  12. Study on optimal surface property of WC-Co cutting tool for aluminium alloy cutting

    Science.gov (United States)

    Nizar, Mohd; Arimatsu, Naoya; Kawamitsu, Hiroshi; Takai, Kazuteru; Fukumoto, Masahiro

    2016-02-01

    The light weight property as well as high corrosion resistance of aluminium alloy has increased their demand especially in automobile industries. Aluminium alloy as a matter of fact has a low melting point and high ductility that severely adhere to the cutting tool surface and cause deterioration of chip evacuation. This problem often resulting in tools breakage. In this paper, in order to impart functions of anti-adhesion, we propose a technique by controlling the grinding marks micro texture on the tool surface by using the blast polishing treatment without any coating technologies. The results show that the tool which underwent polishing treatment reduces the cutting force as well as the aluminium adherence during the initial cutting process, and become worst as the process cutting continues. These results indicate that grinding mark texture improves the anti-adhesion by reducing the contact area during cutting and provide storage for the lubricant. In addition, too much polishing on the tool surface may remove these textures and resultantly worsen the tool performance.

  13. Simulation study of cutting sugarcane using fine sand abrasive waterjet

    Directory of Open Access Journals (Sweden)

    Somjet Thanomputra

    2016-03-01

    Full Text Available Current rotary blade choppers for sugarcane harvesting have the disadvantage of becoming clogged with leaves/cane around the rotating blades causing them to hit the ground and rocks that result in rapid blade wear and tear. Dull blades require repeated cane cutting attempts causing damage to the cane and increasing the cutting force and energy requirements. Thus, the search for alternative, non-contact, cutting options such as waterjet (WJ cutting has been undertaken. The results indicated that WJ cutting has potential but weaknesses have also been reported. Hence, this study explored the use of abrasive fine sand (AWJ to overcome the weaknesses of the pure WJ cutting application. Using the Hoogstrate model and a MATLAB program, AWJ cutting simulation was performed using an orifice and nozzle diameter combination of 0.25 and 0.76 mm at 360 MPa water pressure, respectively, which produced a water flow rate of 1.6 L/min and a power input of 15 kW. Other parameters used in the test included: 80 mesh fine river sand abrasive materials, a specific cutting energy of 8.7 × 10−3 J/mm3 and a fitted cutting efficiency of 0.35. The experimental results revealed that the system was able to cut sugarcane stalks completely at a much farther standoff distance by reducing the traverse speed. The study also showed that cutting sugarcane of 30 and 120 mm diameters would require a traverse speed of 4.4 km/h and 1.1 km/h, respectively. The results implied that limitations should be set for sugarcane thickness for the optimum traverse speed and a standoff distance should be set to no more than 210 mm with a minimum traverse speed of 0.6 km/h.

  14. After the Ribbon Cutting

    DEFF Research Database (Denmark)

    Hodge, Graeme A.; Boulot, Emille; Duffield, Colin

    2017-01-01

    - to long-term governance arrangements. It finds that although industry interviewees agreed PPP governance had improved significantly, they had differing views on how capable Australian states were in governing PPP and how well this task was being undertaken. They were also split on the adequacy......Much attention has gone towards ‘up-front’ processes when delivering infrastructure public–private partnerships (PPPs), but less on how to best govern after the ribbon is cut and the infrastructure built. This paper identifies the primary contractual and institutional governance challenges arising...... in the medium to long term of PPP concession contracts and explores these governance challenges through interviews with high-level PPP industry insiders. The paper presents new findings on the importance of good public administration for successful PPP operation, and on the interesting evolution of medium...

  15. A Black Hole Spectral Signature

    Science.gov (United States)

    Titarchuk, Lev; Laurent, Philippe

    2000-03-01

    An accreting black hole is, by definition, characterized by the drain. Namely, the matter falls into a black hole much the same way as water disappears down a drain matter goes in and nothing comes out. As this can only happen in a black hole, it provides a way to see ``a black hole'', an unique observational signature. The accretion proceeds almost in a free-fall manner close to the black hole horizon, where the strong gravitational field dominates the pressure forces. In this paper we present analytical calculations and Monte-Carlo simulations of the specific features of X-ray spectra formed as a result of upscattering of the soft (disk) photons in the converging inflow (CI) into the black hole. The full relativistic treatment has been implemented to reproduce these spectra. We show that spectra in the soft state of black hole systems (BHS) can be described as the sum of a thermal (disk) component and the convolution of some fraction of this component with the CI upscattering spread (Greens) function. The latter boosted photon component is seen as an extended power-law at energies much higher than the characteristic energy of the soft photons. We demonstrate the stability of the power spectral index over a wide range of the plasma temperature 0 - 10 keV and mass accretion rates (higher than 2 in Eddington units). We also demonstrate that the sharp high energy cutoff occurs at energies of 200-400 keV which are related to the average energy of electrons mec2 impinging upon the event horizon. The spectrum is practically identical to the standard thermal Comptonization spectrum when the CI plasma temperature is getting of order of 50 keV (the typical ones for the hard state of BHS). In this case one can see the effect of the bulk motion only at high energies where there is an excess in the CI spectrum with respect to the pure thermal one. Furthermore we demonstrate that the change of spectral shapes from the soft X-ray state to the hard X-ray state is clearly to be

  16. The diffuse cut-off

    International Nuclear Information System (INIS)

    2014-09-01

    After having recalled the interest of cut-off practices when consumption is higher than production (a cut-off operator turns out some sources of consumption), this publication more particularly addresses the practice of cut-off in the residential sector, also called diffused cut-off. This practice is based on a temporary reduction of electricity consumption in a great number of small sites (for example, a brief interruption of the electricity supply of radiators, hot water tanks, air conditioning devices in dwellings to reduce the total demand of an area). The three main modalities of valorisation of this cut-off power by the operator are presented. Advantages and drawbacks are discussed, and more particularly the impact of cut-off on thermal comfort

  17. Statistical clumped isotope signatures

    Science.gov (United States)

    Röckmann, T.; Popa, M. E.; Krol, M. C.; Hofmann, M. E. G.

    2016-01-01

    High precision measurements of molecules containing more than one heavy isotope may provide novel constraints on element cycles in nature. These so-called clumped isotope signatures are reported relative to the random (stochastic) distribution of heavy isotopes over all available isotopocules of a molecule, which is the conventional reference. When multiple indistinguishable atoms of the same element are present in a molecule, this reference is calculated from the bulk (≈average) isotopic composition of the involved atoms. We show here that this referencing convention leads to apparent negative clumped isotope anomalies (anti-clumping) when the indistinguishable atoms originate from isotopically different populations. Such statistical clumped isotope anomalies must occur in any system where two or more indistinguishable atoms of the same element, but with different isotopic composition, combine in a molecule. The size of the anti-clumping signal is closely related to the difference of the initial isotope ratios of the indistinguishable atoms that have combined. Therefore, a measured statistical clumped isotope anomaly, relative to an expected (e.g. thermodynamical) clumped isotope composition, may allow assessment of the heterogeneity of the isotopic pools of atoms that are the substrate for formation of molecules. PMID:27535168

  18. Tungsten monocrystal cutting without distortion

    International Nuclear Information System (INIS)

    Dudkin, A.Yu.; Matveev, I.V.; Cheremisin, S.M.

    1982-01-01

    Electrolyte with high electric current localization, containing 1-3 % KOH and 2-10 % NH 3 , is suggested to use for electrochemical cutting of tungsten. A cutting device is described which includes a cathode feed mechanism based on electric heating and a circuit of automatic control of an interelectrode gap. Laue patterns obtained from a cut surface are practically the same as ones from the initial monocrystal

  19. Laser Cutting of Different Materials

    Directory of Open Access Journals (Sweden)

    Kadir ÇAVDAR

    2013-08-01

    Full Text Available In this paper; in general potential developments and trends of a particular machining field by extensively evaluating present studies of laser beam machining have been discussed. As it is indicated below, technical literatures have been subsumed under five major headlines: Experimental studies, reviews, optimization researches of the cutting parameters, theoretical modelling studies of laser beam cutting and academic studies relating to laser cutting

  20. Environmental sampling: Issues for the cut-off regime

    International Nuclear Information System (INIS)

    Fearey, B.L.

    1995-01-01

    The fissile material cut-off treaty (FMCT) initiative under the Conference on Disarmament mandate is envisioned to include certain aspects of environmental sampling and monitoring. One of the intents of this treaty is to bring certain non-NPT signatories (e.g., threshold states) under this treaty agreement along with the nuclear weapon states (NWSs). This paper provides a brief overview of some of the relevant issues that may be involved in the implementation and use of environmental monitoring for (1) verification of the cut-off regime declarations, (2) the detection of undeclared activities, and, (3) application in non-routine inspections. The intent is to provide backstopping information important for treaty negotiators. Specific issues addressed within this paper include signature sampling, differences in the proposed detection regime, potential signature integrators, specific examples and spoofing concerns. Many of these issues must be carefully considered and weighed in order to create a credibly verifiable inspection regime. Importantly, the cut-off treaty must enable nondiscriminatory implementation, while carefully assuring that nonproliferation treaty requirements are maintained (i.e., preventing unintentional release of critical weapons design information--potentially through environmental sampling and analysis)

  1. CUTTING BACK THE STEM: CULTIVATING LIBERAL ARTS IN OFFICER ACCESSIONS

    Science.gov (United States)

    2016-06-01

    Force Personnel Center, October 2015), 255. 35 Line of the Air Force excludes the medical, legal , and chaplain professional corps where licensure or...with an enormous potential for change in the late teen years. Choices determine the qualities of the brain. By concentrating on math, music , or...cut off from overland transportation routes. Never intended as a long-term solution, the operation was a stopgap measure to buy time while seeking a

  2. Retail applications of signature verification

    Science.gov (United States)

    Zimmerman, Thomas G.; Russell, Gregory F.; Heilper, Andre; Smith, Barton A.; Hu, Jianying; Markman, Dmitry; Graham, Jon E.; Drews, Clemens

    2004-08-01

    The dramatic rise in identity theft, the ever pressing need to provide convenience in checkout services to attract and retain loyal customers, and the growing use of multi-function signature captures devices in the retail sector provides favorable conditions for the deployment of dynamic signature verification (DSV) in retail settings. We report on the development of a DSV system to meet the needs of the retail sector. We currently have a database of approximately 10,000 signatures collected from 600 subjects and forgers. Previous work at IBM on DSV has been merged and extended to achieve robust performance on pen position data available from commercial point of sale hardware, achieving equal error rates on skilled forgeries and authentic signatures of 1.5% to 4%.

  3. Password-based digital signatures

    OpenAIRE

    Sivagnanasuntharam, Sangeepan

    2013-01-01

    This thesis is about implementing a digital signature scheme proposed by associate professor Kristian Gjøsteen and Oystein Thuen.The thesis explains the implementation, the challenges met and a security assessment of the implementation.

  4. Initial Semantics for Strengthened Signatures

    Directory of Open Access Journals (Sweden)

    André Hirschowitz

    2012-02-01

    Full Text Available We give a new general definition of arity, yielding the companion notions of signature and associated syntax. This setting is modular in the sense requested by Ghani and Uustalu: merging two extensions of syntax corresponds to building an amalgamated sum. These signatures are too general in the sense that we are not able to prove the existence of an associated syntax in this general context. So we have to select arities and signatures for which there exists the desired initial monad. For this, we follow a track opened by Matthes and Uustalu: we introduce a notion of strengthened arity and prove that the corresponding signatures have initial semantics (i.e. associated syntax. Our strengthened arities admit colimits, which allows the treatment of the λ-calculus with explicit substitution.

  5. Sensitive analysis of a finite element model of orthogonal cutting

    Science.gov (United States)

    Brocail, J.; Watremez, M.; Dubar, L.

    2011-01-01

    This paper presents a two-dimensional finite element model of orthogonal cutting. The proposed model has been developed with Abaqus/explicit software. An Arbitrary Lagrangian-Eulerian (ALE) formulation is used to predict chip formation, temperature, chip-tool contact length, chip thickness, and cutting forces. This numerical model of orthogonal cutting will be validated by comparing these process variables to experimental and numerical results obtained by Filice et al. [1]. This model can be considered to be reliable enough to make qualitative analysis of entry parameters related to cutting process and frictional models. A sensitivity analysis is conducted on the main entry parameters (coefficients of the Johnson-Cook law, and contact parameters) with the finite element model. This analysis is performed with two levels for each factor. The sensitivity analysis realised with the numerical model on the entry parameters has allowed the identification of significant parameters and the margin identification of parameters.

  6. Precision Machining When Cutting with Leading Plastic Deformation

    Directory of Open Access Journals (Sweden)

    N. A. Yaroslavtseva

    2017-01-01

    Full Text Available Keeping up the product competitiveness continually requires solving the problems of reducing time for product creation and material costs for its production and ensuring the maximum conformity of the product quality with the individual requirements of a particular consumer. It is especially difficult to implement these tasks in product manufacturing from the hard-to-machine steels and alloys with extremely low production rate in machining (often 10-20 times lower than when cutting the ordinary structural steels.Currently, one of the promising ways to improve the cutting process of hard-to-machine materials and quality of parts made from these materials is development and application of combined processing methods, which use additional energy sources to act on the machined material in the cutting zone. A BMSTU-developed cutting method with leading plastic deformation (LPD, which acts to raise the production rate, gain the cutting tool-life, reduce the surface roughness, improve the accuracy of processing and the performance characteristics of products, ensure the reliable flow chip control, and improve the labor conditions, belongs to such sort of methods.One of the most important indicators of processing quality that has a great impact on the operation and cost characteristics of the product and on the machining rate as well is the accuracy of processing. In cutting, the processing errors largely arise from the elastic deformations of a technological system when the cutting force, and, in particular, the radial component of the cutting force, acts on it.The deforming devices, used in cutting with LPD, being located as a rule, on the diametrically opposite side with respect to the cutting zone, act on the technological system as vibration dampers. In addition, as studies have shown, the choice of a rational direction for applying LPD load helps to compensate partially or completely the cutting force radial component effect on the technological

  7. Laser cutting of laminated sheet material: a modeling exercise

    Science.gov (United States)

    de Graaf, Roelof F.; Meijer, Johan

    1997-08-01

    Laser cutting has been investigated for a number of aluminum-synthetic laminates, newly developed materials for the aeronautic and automotive industry. The materials consist of alternating aluminum and synthetic layers. It is shown that these materials can be cut at rates comparable to those of homogeneous aluminum alloys. The cuts show little dross attachment. Also some damage on the synthetic layers has to be accepted. These results initiated a modeling exercise, which resulted in a numerical simulation code. The applied cutting model is based on describing the material in several horizontal layers, each with its own specific thermophysical and optical properties. The separate layers are coupled by known mass, energy and force balanced equations.

  8. Experimental Research Using of MQL in Metal Cutting

    Directory of Open Access Journals (Sweden)

    G. Globočki Lakić

    2013-12-01

    Full Text Available In this paper an effect of using of minimal quantity lubrication (MQL technique in turning operations is presented. Experimental research was performed on carbon steel C45E. Technological parameters: depth of cut, feed rate and cutting speed were adjusted to semi-machining and roughing. Higher values ​​of feed and cutting speed were used, than recommended from literature and different types of cooling and lubrication in turning conditions were applied. As a conventional procedure and technology, lubrication with flooding was applied. As special lubrication the MQL technique was used. During research, monitoring of the cutting force, chip shape, tool wear and surface roughness was performed. Relations between parameters, material machinability and economy of process were analyzed.

  9. Application of response surface methodology for determining cutting ...

    Indian Academy of Sciences (India)

    Cutting force is classified among the most important technological parameter to control in machining process. It is the background for the evaluation of the necessary power machining. (choice of the electric motor). It is also used for dimensioning of machine tool components and the tool body. It influences machining system ...

  10. Cutting concrete with abrasion jet

    International Nuclear Information System (INIS)

    Yie, G.G.

    1982-01-01

    Fluidyne Corporation has developed a unique process and apparatus that allow selected abrasives to be introduced into high-speed waterjet to produce abrasive-entrained waterjet that has high material-cutting capabilities, which is termed by Fluidyne as the Abrasion Jet. Such Abrasion Jet has demonstrated capability in cutting hard rock and concrete at a modest pressure of less than 1360 bars (20,000 psi) and a power input of less than 45 kW (60 horsepower). Abrasion Jet cutting of concrete is characterized by its high rate of cutting, flexible operation, good cut quality, and relatively low costs. This paper presents a general description of this technology together with discussions of recent test results and how it could be applied to nuclear decontamination and decommissioning work. 8 references

  11. DISPOSITIVO TRANSDUCTOR PARA LA MEDICIÓN DE FUERZA Y VELOCIDAD EN UNA TAREA DE CORTE CON ESCALPELO DISPOSITIVO TRANSDUCTOR PARA A MEDIÇÃO DE FORÇA E VELOCIDADE EM UMA TAREFA DE CORTE COM ESCALPELO TRANSDUCER DEVICE FOR MEASURING FORCE AND SPEED IN A TASK OF SCALPEL CUTTING

    Directory of Open Access Journals (Sweden)

    Edilberto Mejía

    2010-12-01

    finalidade desenvolveu-se um software em linguagem de programação C #. Todos os ensaios se efetuaram sobre o mesmo tecido e com a mesma rotina para realizar uma medição da repetibilidade do corte. Os resultados foram registados em tabelas, para fins de análise estatística e representação gráfica.This paper shows the design and manufacture of a mechatronic device, capable of measuring force and speed in a cutting work done with a scalpel. A study based on the finite element method was made, in order to record the force required to break the tissue (chicken breast having a theoretical framework as the benchmark of the results obtained in the cutting tests. It was used, as the primary measuring device, a sensor type Flexiforce A201-25. The device was attached, as a working tool, to an industrial robotic arm programmed with a crosssection routine. The cutting speed of the implemented device was sensed through a camera by tracking a marker set previously for this purpose, software in C # programming language was developed. All tests were performed on the same tissue and with the same routine to perform a measurement of cutting repeatability. The results were recorded in tables, for purposes of statistical analysis, and graphical representation.

  12. SIGNATURE: A workbench for gene expression signature analysis

    Directory of Open Access Journals (Sweden)

    Chang Jeffrey T

    2011-11-01

    Full Text Available Abstract Background The biological phenotype of a cell, such as a characteristic visual image or behavior, reflects activities derived from the expression of collections of genes. As such, an ability to measure the expression of these genes provides an opportunity to develop more precise and varied sets of phenotypes. However, to use this approach requires computational methods that are difficult to implement and apply, and thus there is a critical need for intelligent software tools that can reduce the technical burden of the analysis. Tools for gene expression analyses are unusually difficult to implement in a user-friendly way because their application requires a combination of biological data curation, statistical computational methods, and database expertise. Results We have developed SIGNATURE, a web-based resource that simplifies gene expression signature analysis by providing software, data, and protocols to perform the analysis successfully. This resource uses Bayesian methods for processing gene expression data coupled with a curated database of gene expression signatures, all carried out within a GenePattern web interface for easy use and access. Conclusions SIGNATURE is available for public use at http://genepattern.genome.duke.edu/signature/.

  13. Simulating realistic predator signatures in quantitative fatty acid signature analysis

    Science.gov (United States)

    Bromaghin, Jeffrey F.

    2015-01-01

    Diet estimation is an important field within quantitative ecology, providing critical insights into many aspects of ecology and community dynamics. Quantitative fatty acid signature analysis (QFASA) is a prominent method of diet estimation, particularly for marine mammal and bird species. Investigators using QFASA commonly use computer simulation to evaluate statistical characteristics of diet estimators for the populations they study. Similar computer simulations have been used to explore and compare the performance of different variations of the original QFASA diet estimator. In both cases, computer simulations involve bootstrap sampling prey signature data to construct pseudo-predator signatures with known properties. However, bootstrap sample sizes have been selected arbitrarily and pseudo-predator signatures therefore may not have realistic properties. I develop an algorithm to objectively establish bootstrap sample sizes that generates pseudo-predator signatures with realistic properties, thereby enhancing the utility of computer simulation for assessing QFASA estimator performance. The algorithm also appears to be computationally efficient, resulting in bootstrap sample sizes that are smaller than those commonly used. I illustrate the algorithm with an example using data from Chukchi Sea polar bears (Ursus maritimus) and their marine mammal prey. The concepts underlying the approach may have value in other areas of quantitative ecology in which bootstrap samples are post-processed prior to their use.

  14. Influence of the surface layer characteristics on the regularities of the cutting process

    Directory of Open Access Journals (Sweden)

    Krainev Dmitriy V.

    2017-01-01

    Full Text Available The article considers the influence of the surface layer characteristics on the regularities of the cutting process and the formation of the quality of the surface machined. This effect has been confirmed by the study results of the combined cutting method with advanced plastic deformation (APD. The work estimates the impact of the change in the surface layer properties on the forces and temperature of cutting, stability of the chip formation and quality parameters of the surface machined.

  15. Application of Taguchi method for cutting force optimization in rock ...

    Indian Academy of Sciences (India)

    As a result of this increase, there has been recently more attention for sustainability during their productions .... tical measure of performance in Taguchi method was subsequently used to analyse the results. Table 3. .... The performance of circular diamond sawblades was evaluated for Fc with respect to the Eq. (14) and the ...

  16. Application of Taguchi method for cutting force optimization in rock ...

    Indian Academy of Sciences (India)

    The use of natural stones as a construction and building material has been increasing worldwide. As a result of this increase, there has been recently more attention for sustainability during their productions (Karakurt et al 2012). Circular diamond .... Porosity (%). 1.50. Ultrasonic velocity (m/s). 4140. Cerchar abrasion Index.

  17. Study of Effect of Impacting Direction on Abrasive Nanometric Cutting Process with Molecular Dynamics

    Science.gov (United States)

    Li, Junye; Meng, Wenqing; Dong, Kun; Zhang, Xinming; Zhao, Weihong

    2018-01-01

    Abrasive flow polishing plays an important part in modern ultra-precision machining. Ultrafine particles suspended in the medium of abrasive flow removes the material in nanoscale. In this paper, three-dimensional molecular dynamics (MD) simulations are performed to investigate the effect of impacting direction on abrasive cutting process during abrasive flow polishing. The molecular dynamics simulation software Lammps was used to simulate the cutting of single crystal copper with SiC abrasive grains at different cutting angles (0o-45o). At a constant friction coefficient, we found a direct relation between cutting angle and cutting force, which ultimately increases the number of dislocation during abrasive flow machining. Our theoretical study reveal that a small cutting angle is beneficial for improving surface quality and reducing internal defects in the workpiece. However, there is no obvious relationship between cutting angle and friction coefficient.

  18. Study of Effect of Impacting Direction on Abrasive Nanometric Cutting Process with Molecular Dynamics.

    Science.gov (United States)

    Li, Junye; Meng, Wenqing; Dong, Kun; Zhang, Xinming; Zhao, Weihong

    2018-01-11

    Abrasive flow polishing plays an important part in modern ultra-precision machining. Ultrafine particles suspended in the medium of abrasive flow removes the material in nanoscale. In this paper, three-dimensional molecular dynamics (MD) simulations are performed to investigate the effect of impacting direction on abrasive cutting process during abrasive flow polishing. The molecular dynamics simulation software Lammps was used to simulate the cutting of single crystal copper with SiC abrasive grains at different cutting angles (0 o -45 o ). At a constant friction coefficient, we found a direct relation between cutting angle and cutting force, which ultimately increases the number of dislocation during abrasive flow machining. Our theoretical study reveal that a small cutting angle is beneficial for improving surface quality and reducing internal defects in the workpiece. However, there is no obvious relationship between cutting angle and friction coefficient.

  19. Preferences of cut flowers consumers

    Directory of Open Access Journals (Sweden)

    Sylwia Kierczyńska

    2010-01-01

    Full Text Available The results of interviews suggest that majority of the cut flowers’ consumers has favourite kind of flower, among which most frequently pointed one was the rose. More than half of the interviewed favour the uniform colour of cut flowers and red colour was the most favourite one. The subtle smell of flowers was the most preferable one but the intensive fragrance was favoured for more consumers than odourless flowers. The data from selected florists’ confirm the information from interviews – in spite of the occasion, roses were the most demanded cut flowers.

  20. Laser cutting of Kevlar laminates

    Energy Technology Data Exchange (ETDEWEB)

    VanCleave, R.A.

    1977-09-01

    An investigation has been conducted of the use of laser energy for cutting contours, diameters, and holes in flat and shaped Kevlar 49 fiber-reinforced epoxy laminates as an alternate to conventional machining. The investigation has shown that flat laminates 6.35 mm thick may be cut without backup by using a high-powered (1000-watt) continuous wave CO/sub 2/ laser at high feedrates (33.87 mm per second). The cut produced was free of the burrs and delaminations resulting from conventional machining methods without intimate contact backup. In addition, the process cycle time was greatly reduced.

  1. Regge cuts in inclusive reactions

    International Nuclear Information System (INIS)

    Paige, F.E.; Trueman, T.L.

    1975-01-01

    The contribution of Regge cuts to single-particle inclusive processes is analyzed using the techniques of Gribov. The dependence of these contributions on the polarization state of the target is emphasized. A general formula is obtained and certain contributions to it are calculated. It is not possible, however, to reduce this to a simple, powerful formula expressing the total cut contribution in terms of other measurable quantities, as can be done for the cut contribution to the total cross section. The reasons for this are discussed in detail. The single-particle intermediate states, analogous to the absorption model for elastic scattering, are explicitly calculated as an illustration

  2. Military Tactical Aircraft Engine Noise Matching to Infrared Signatures

    Science.gov (United States)

    2016-12-16

    Alternating Current AFB – Air Force Base CFD – Computational Fluid Dynamics CO2 – Carbon Dioxide FY – Fiscal Year IR – Infrared KAFB – Kirtland Air...thereby rendering insignificant the absorptive effects of atmosphere. Because the plume is the primary source of acoustic emissions in situations that...N/A This report builds on theoretical analysis of jet engine infrared signatures and their potential relationships to jet engine acoustic emissions

  3. Signature effect in the SU(3) limit of SU(6) particle-quadrupole phonon coupling model (PTQM)

    International Nuclear Information System (INIS)

    Paar, V.; Brant, S.

    1981-09-01

    Systematic deviations from the J(J + 1) energy rule in the SU(3) limit of PTQM are studied and interpreted in terms of signature from the rotational model. The signature effect, which is in the rotational mode introduced via the Coriolis force, is generated here by the correlation of PTQM. (author)

  4. Hard particle effect on surface generation in nano-cutting

    Science.gov (United States)

    Xu, Feifei; Fang, Fengzhou; Zhang, Xiaodong

    2017-12-01

    The influence of the hard particle on the surface generation, plastic deformation and processing forces in nano-cutting of aluminum is investigated by means of molecular dynamics simulations. In this investigation, a hard particle which is simplified as a diamond ball is embedded under the free surface of workpiece with different depths. The influence of the position of the hard ball on the surface generation and other material removal mechanism, such as the movement of the ball under the action of cutting tool edge, is revealed. The results show that when the hard particle is removed, only a small shallow pit is left on the machined surface. Otherwise, it is pressed down to the subsurface of the workpiece left larger and deeper pit on the generated surface. Besides that, the hard particle in the workpiece would increase the processing force when the cutting tool edge or the plastic carriers interact with the hard particle. It is helpful to optimize the cutting parameters and material properties for obtaining better surface quality in nano-cutting of composites or other materials with micro/nanoscale hard particles in it.

  5. Less-invasive non-embedded cell cutting by nanomanipulation and vibrating nanoknife

    Science.gov (United States)

    Shang, Wanfeng; Li, Dengfeng; Lu, Haojian; Fukuda, Toshio; Shen, Yajing

    2017-01-01

    The less-invasive non-embedded cell cutting or slicing technique provides opportunities for a bio-study at subcellular scale, but there are few effective solutions available at the current stage. This paper reports a robot-aided vibrating system for less-invasive non-embedded cell cutting and investigates the role of key vibrating parameters in the cell cutting process. First, a nanoknife with sharp angle 5° is fabricated from a commercial atomic force microscope cantilever by focused ion beam etching and a vibrating system is constructed from a piezo actuator. Then, they are integrated with a self-developed nanorobotic manipulation system inside an environment scanning electron microscope. After that, we choose yeast cells as the sample to implement the vibrating cutting and investigate the effect of vibrating parameters (frequency and amplitude) on cell cutting quality. The results clearly indicate that the vibrating nanoknife is able to reduce the cutting force and improve the cutting quality. It is also suggested that the repeated load-unload (impact) cycle is the main reason for the better performance of vibrating cutting. The effect of vibrating parameters at small scale benefits our fundamental understanding on cell mechanics, and this research paves a way for the low-destructive non-embedded cell cutting and promotes the practical cell cutting techniques.

  6. Measurement of tool forces in diamond turning

    Energy Technology Data Exchange (ETDEWEB)

    Drescher, J.; Dow, T.A.

    1988-12-01

    A dynamometer has been designed and built to measure forces in diamond turning. The design includes a 3-component, piezoelectric transducer. Initial experiments with this dynamometer system included verification of its predicted dynamic characteristics as well as a detailed study of cutting parameters. Many cutting experiments have been conducted on OFHC Copper and 6061-T6 Aluminum. Tests have involved investigation of velocity effects, and the effects of depth and feedrate on tool forces. Velocity has been determined to have negligible effects between 4 and 21 m/s. Forces generally increase with increasing depth of cut. Increasing feedrate does not necessarily lead to higher forces. Results suggest that a simple model may not be sufficient to describe the forces produced in the diamond turning process.

  7. Effect of Forefoot Strike on Lower Extremity Muscle Activity and Knee Joint Angle During Cutting in Female Team Handball Players.

    Science.gov (United States)

    Yoshida, Naruto; Kunugi, Shun; Mashimo, Sonoko; Okuma, Yoshihiro; Masunari, Akihiko; Miyazaki, Shogo; Hisajima, Tatsuya; Miyakawa, Shumpei

    2015-06-01

    The purpose of this study is to examine the effects of different strike forms, during cutting, on knee joint angle and lower limb muscle activity. Surface electromyography was used to measure muscle activity in individuals performing cutting manoeuvres involving either rearfoot strikes (RFS) or forefoot strikes (FFS). Three-dimensional motion analysis was used to calculate changes in knee angles, during cutting, and to determine the relationship between muscle activity and knee joint angle. Force plates were synchronized with electromyography measurements to compare muscle activity immediately before and after foot strike. The valgus angle tends to be smaller during FFS cutting than during RFS cutting. Just prior to ground contact, biceps femoris, semitendinosus, and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was greater during RFS cutting. Immediately after ground contact, biceps femoris and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was significantly lower during FFS cutting. The results of the present study suggest that the hamstrings demonstrate greater activity, immediately after foot strike, during FFS cutting than during RFS cutting. Thus, FFS cutting may involve a lower risk of anterior cruciate ligament injury than does RFS cutting.

  8. Preferences of cut flowers consumers

    OpenAIRE

    Sylwia Kierczyńska

    2010-01-01

    The results of interviews suggest that majority of the cut flowers’ consumers has favourite kind of flower, among which most frequently pointed one was the rose. More than half of the interviewed favour the uniform colour of cut flowers and red colour was the most favourite one. The subtle smell of flowers was the most preferable one but the intensive fragrance was favoured for more consumers than odourless flowers. The data from selected florists’ confirm the information from interviews – in...

  9. Interactive cutting path analysis programs

    Science.gov (United States)

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

    1975-01-01

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

  10. Economic technology of laser cutting

    Science.gov (United States)

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

    2000-02-01

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

  11. Five Guidelines for Selecting Hydrological Signatures

    Science.gov (United States)

    McMillan, H. K.; Westerberg, I.; Branger, F.

    2017-12-01

    Hydrological signatures are index values derived from observed or modeled series of hydrological data such as rainfall, flow or soil moisture. They are designed to extract relevant information about hydrological behavior, such as to identify dominant processes, and to determine the strength, speed and spatiotemporal variability of the rainfall-runoff response. Hydrological signatures play an important role in model evaluation. They allow us to test whether particular model structures or parameter sets accurately reproduce the runoff generation processes within the watershed of interest. Most modeling studies use a selection of different signatures to capture different aspects of the catchment response, for example evaluating overall flow distribution as well as high and low flow extremes and flow timing. Such studies often choose their own set of signatures, or may borrow subsets of signatures used in multiple other works. The link between signature values and hydrological processes is not always straightforward, leading to uncertainty and variability in hydrologists' signature choices. In this presentation, we aim to encourage a more rigorous approach to hydrological signature selection, which considers the ability of signatures to represent hydrological behavior and underlying processes for the catchment and application in question. To this end, we propose a set of guidelines for selecting hydrological signatures. We describe five criteria that any hydrological signature should conform to: Identifiability, Robustness, Consistency, Representativeness, and Discriminatory Power. We describe an example of the design process for a signature, assessing possible signature designs against the guidelines above. Due to their ubiquity, we chose a signature related to the Flow Duration Curve, selecting the FDC mid-section slope as a proposed signature to quantify catchment overall behavior and flashiness. We demonstrate how assessment against each guideline could be used to

  12. The Effect of Cutting Speed in Metallic Glass Grinding

    International Nuclear Information System (INIS)

    Serbest, Erdinc; Bakkal, Mustafa; Karipcin, Ilker; Derin, Bora

    2011-01-01

    In this paper, the effects of the cutting speed in metallic glass grinding were investigated in dry conditions. The results showed that grinding forces decrease as grinding energy increase with the increasing cutting speeds. The present investigations on ground surface and grinding chips morphologies -shows that material removal and surface formation of the BMG are mainly due to the ductile chip deformation and ploughing as well as brittle fracture of some particles from the edges of the tracks. The roughness values obtained with the Cubic Boron Nitride wheels are acceptable for the grinding operation.

  13. Twice cutting method reduces tibial cutting error in unicompartmental knee arthroplasty.

    Science.gov (United States)

    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 (Pcutting the tibia horizontally twice using the same cutting guide reduced cutting error in the coronal plane. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Convention on nuclear safety. Signature, ratification, acceptance, approval or accession. Status as of 17 March 1997

    International Nuclear Information System (INIS)

    1997-01-01

    The document presents the status as of 17 March 1997 of signature, ratification, acceptance, approval or accession by Member States of the Convention on Nuclear Safety adopted on 17 June 1994 by the Diplomatic Conference convened by the IAEA at its Headquarters between 14-17 June 1994. The Convention entered into force on 24 October 1996. There are 65 signatories and 35 parties. Reservations/declarations deposited upon signature are also included

  15. Motif signatures of transcribed enhancers

    KAUST Repository

    Kleftogiannis, Dimitrios

    2017-09-14

    In mammalian cells, transcribed enhancers (TrEn) play important roles in the initiation of gene expression and maintenance of gene expression levels in spatiotemporal manner. One of the most challenging questions in biology today is how the genomic characteristics of enhancers relate to enhancer activities. This is particularly critical, as several recent studies have linked enhancer sequence motifs to specific functional roles. To date, only a limited number of enhancer sequence characteristics have been investigated, leaving space for exploring the enhancers genomic code in a more systematic way. To address this problem, we developed a novel computational method, TELS, aimed at identifying predictive cell type/tissue specific motif signatures. We used TELS to compile a comprehensive catalog of motif signatures for all known TrEn identified by the FANTOM5 consortium across 112 human primary cells and tissues. Our results confirm that distinct cell type/tissue specific motif signatures characterize TrEn. These signatures allow discriminating successfully a) TrEn from random controls, proxy of non-enhancer activity, and b) cell type/tissue specific TrEn from enhancers expressed and transcribed in different cell types/tissues. TELS codes and datasets are publicly available at http://www.cbrc.kaust.edu.sa/TELS.

  16. Signature simulation of mixed materials

    Science.gov (United States)

    Carson, Tyler D.; Salvaggio, Carl

    2015-05-01

    Soil target signatures vary due to geometry, chemical composition, and scene radiometry. Although radiative transfer models and function-fit physical models may describe certain targets in limited depth, the ability to incorporate all three signature variables is difficult. This work describes a method to simulate the transient signatures of soil by first considering scene geometry synthetically created using 3D physics engines. Through the assignment of spectral data from the Nonconventional Exploitation Factors Data System (NEFDS), the synthetic scene is represented as a physical mixture of particles. Finally, first principles radiometry is modeled using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model. With DIRSIG, radiometric and sensing conditions were systematically manipulated to produce and record goniometric signatures. The implementation of this virtual goniometer allows users to examine how a target bidirectional reflectance distribution function (BRDF) will change with geometry, composition, and illumination direction. By using 3D computer graphics models, this process does not require geometric assumptions that are native to many radiative transfer models. It delivers a discrete method to circumnavigate the significant cost of time and treasure associated with hardware-based goniometric data collections.

  17. Epigenetic Signatures of Cigarette Smoking

    NARCIS (Netherlands)

    R. Joehanes (Roby); Just, A.C. (Allan C.); R.E. Marioni (Riccardo); L.C. Pilling (Luke); L.M. Reynolds (Lindsay); Mandaviya, P.R. (Pooja R.); W. Guan (Weihua); Xu, T. (Tao); C.E. Elks (Cathy); Aslibekyan, S. (Stella); H. Moreno-Macías (Hortensia); J.A. Smith (Jennifer A); J. Brody (Jennifer); Dhingra, R. (Radhika); P. Yousefi (Paul); J.S. Pankow (James); Kunze, S. (Sonja); Shah, S.H. (Sonia H.); A.F. McRae (Allan F.); K. Lohman (Kurt); Sha, J. (Jin); D. Absher (Devin); L. Ferrucci (Luigi); Zhao, W. (Wei); E.W. Demerath (Ellen); J. Bressler (Jan); M.L. Grove (Megan); T. Huan (Tianxiao); C. Liu (Chunyu); Mendelson, M.M. (Michael M.); C. Yao (Chen); D.P. Kiel (Douglas P.); A. Peters (Annette); R. Wang-Sattler (Rui); P.M. Visscher (Peter); N.R. Wray (Naomi); J.M. Starr (John); Ding, J. (Jingzhong); Rodriguez, C.J. (Carlos J.); N.J. Wareham (Nick); Irvin, M.R. (Marguerite R.); Zhi, D. (Degui); M. Barrdahl (Myrto); P. Vineis (Paolo); Ambatipudi, S. (Srikant); A.G. Uitterlinden (André); A. Hofman (Albert); Schwartz, J. (Joel); Colicino, E. (Elena); Hou, L. (Lifang); Vokonas, P.S. (Pantel S.); D.G. Hernandez (Dena); A. Singleton (Andrew); S. Bandinelli (Stefania); S.T. Turner (Stephen); E.B. Ware (Erin B.); Smith, A.K. (Alicia K.); T. Klengel (Torsten); E.B. Binder (Elisabeth B.); B.M. Psaty (Bruce); K.D. Taylor (Kent); S.A. Gharib (Sina); Swenson, B.R. (Brenton R.); Liang, L. (Liming); D.L. Demeo (Dawn L.); G.T. O'Connor (George); Z. Herceg (Zdenko); Ressler, K.J. (Kerry J.); K.N. Conneely (Karen N.); N. Sotoodehnia (Nona); Kardia, S.L.R. (Sharon L. R.); D. Melzer (David); A.A. Baccarelli (Andrea A.); J.B.J. van Meurs (Joyce); I. Romieu (Isabelle); D.K. Arnett (Donna); Ong, K.K. (Ken K.); Y. Liu (YongMei); M. Waldenberger (Melanie); I.J. Deary (Ian J.); M. Fornage (Myriam); D. Levy (Daniel); S.J. London (Stephanie J.)

    2016-01-01

    textabstractBackground-DNA methylation leaves a long-term signature of smoking exposure and is one potential mechanism by which tobacco exposure predisposes to adverse health outcomes, such as cancers, osteoporosis, lung, and cardiovascular disorders. Methods and Results-To comprehensively determine

  18. Signature Pedagogy in Theatre Arts

    Science.gov (United States)

    Kornetsky, Lisa

    2017-01-01

    Critique in undergraduate theatre programs is at the heart of training actors at all levels. It is accepted as the signature pedagogy and is practiced in multiple ways. This essay defines critique and presents the case for why it is used as the single most important way that performers come to understand the language, values, and discourse of the…

  19. Galaxy interactions : The HI signature

    NARCIS (Netherlands)

    Sancisi, R; Barnes, JE; Sanders, DB

    1999-01-01

    HI observations are an excellent tool for investigating tidal interactions. Ongoing major and minor interactions which can lead to traumatic mergers or to accretion and the triggering of star formation, show distinct HI signatures. Interactions and mergers in the recent past can also be recognized

  20. Unified Haptic System Using Three Kinds of Cutting Devices for the Basic Use of Medical Application

    Science.gov (United States)

    Honma, Satoru; Wakamatsu, Hidetoshi

    Most training simulators of surgery have simply required manipulation of organic models with their deformation by a single operating device. In order to operate them by various kinds of operating devices, we hereby propose a new type of force-display system based on the combination of the haptic cutting systems of knife, scissors and saw, considering the dynamics of cutting operation of materials mathematically analyzed from their corresponding physical viewpoints. The proposed system is well confirmed to represent the dynamic deformation of virtual objects during their operation inclusive of their incidental cutting force.

  1. Extensions of cutting problems: setups

    Directory of Open Access Journals (Sweden)

    Sebastian Henn

    2013-08-01

    Full Text Available Even though the body of literature in the area of cutting and packing is growing rapidly, research seems to focus on standard problems in the first place, while practical aspects are less frequently dealt with. This is particularly true for setup processes which arise in industrial cutting processes whenever a new cutting pattern is started (i.e. a pattern is different from its predecessor and the cutting equipment has to be prepared in order to meet the technological requirements of the new pattern. Setups involve the consumption of resources and the loss of production time capacity. Therefore, consequences of this kind must explicitly be taken into account for the planning and control of industrial cutting processes. This results in extensions to traditional models which will be reviewed here. We show how setups can be represented in such models, and we report on the algorithms which have been suggested for the determination of solutions of the respective models. We discuss the value of these approaches and finally point out potential directions of future research.

  2. Cutting inlays with a laser

    Science.gov (United States)

    Swaczyna, Irena; Grabczewski, Zbigniew

    1995-03-01

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

  3. Cutting and Folding for Tunable Materials Properties

    Science.gov (United States)

    Damasceno, Pablo; Dodd, Paul; Shyu, Terry; Shlian, Matthew; Shtein, Max; Kotov, Nicholas; Glotzer, Sharon

    2014-03-01

    Despite the small set of building blocks used for their assembly, naturally occurring materials such as proteins show remarkable diversity in their mechanical properties ranging from something resembling rubber-low stiffness, high resilience and extensibility-to silk-high stiffness and strength. Moreover, their self-folding properties inspire the design of structures capable of tunable reconfiguration. Motivated by such versatility, we report on simulations and experiments for the design of nanocomposites sheets whose mechanical properties can be made tunable via ``secondary structures'' patterning. Our simulations reveal the main cutting features needed to obtain desired material extensibility. Additionally, we study how similar sheets could self-fold into their desired ``native'' structure via stochastic forces. Our results open the possibilities for manufacture of flexible and reconfigurable materials with targeted strength and extensibility. Research supported by the National Science Foundation, Emerging Frontiers in Research and Innovation Award # EFRI-1240264.

  4. Compensations for increased rotational inertia during human cutting turns.

    Science.gov (United States)

    Qiao, Mu; Brown, Brian; Jindrich, Devin L

    2014-02-01

    Locomotion in a complex environment is often not steady state, but unsteady locomotion (stability and maneuverability) is not well understood. We investigated the strategies used by humans to perform sidestep cutting turns when running. Previous studies have argued that because humans have small yaw rotational moments of inertia relative to body mass, deceleratory forces in the initial velocity direction that occur during the turning step, or 'braking' forces, could function to prevent body over-rotation during turns. We tested this hypothesis by increasing body rotational inertia and testing whether braking forces during stance decreased. We recorded ground reaction force and body kinematics from seven participants performing 45 deg sidestep cutting turns and straight running at five levels of body rotational inertia, with increases up to fourfold. Contrary to our prediction, braking forces remained consistent at different rotational inertias, facilitated by anticipatory changes to body rotational speed. Increasing inertia revealed that the opposing effects of several turning parameters, including rotation due to symmetrical anterior-posterior forces, result in a system that can compensate for fourfold changes in rotational inertia with less than 50% changes to rotational velocity. These results suggest that in submaximal effort turning, legged systems may be robust to changes in morphological parameters, and that compensations can involve relatively minor adjustments between steps to change initial stance conditions.

  5. Evaluation of a Novel Controlled Cutting Fluid Impinging Supply System When Machining Titanium Alloys

    Directory of Open Access Journals (Sweden)

    Salah Gariani

    2017-05-01

    Full Text Available Following a comprehensive review on titanium machining and methods of cutting fluid application, this paper presents a new Controlled cutting fluid impinging supply system (Cut‐list developed to deliver an accurate amount of cutting fluid into the machining zone via wellpositioned coherent nozzles based on the calculation of the heat generated. The performance of the new system was evaluated against a conventional flood cutting fluid supply system during step shoulder milling of Ti‐6Al‐4V using vegetable oil‐based cutting fluid. The comparison was performed at different cutting speeds and feed rates. Comparison measures/indicators were cutting force, workpiece temperature, tool flank wear, burr formation and average surface roughness (Ra. The new system provided significant reductions in cutting fluid consumption of up to 42%. Additionally, reductions in cutting force, tool flank wear and burr height of 16.41%, 46.77%, and 31.70% were recorded, respectively. Smaller Ra values were also found with the use of the new system.

  6. Sidestep cutting technique and knee abduction loading: implications for ACL prevention exercises.

    Science.gov (United States)

    Kristianslund, Eirik; Faul, Oliver; Bahr, Roald; Myklebust, Grethe; Krosshaug, Tron

    2014-05-01

    Sidestep cutting technique is essential in programmes to prevent anterior cruciate ligament (ACL) injury. A better understanding of how technique affects potentially harmful joint loading may improve prevention programmes. The purpose of this study was to investigate the effect of sidestep cutting technique on maximum knee abduction moments. Cross-sectional study. Whole-body kinematics and knee joint kinetics were calculated in 123 female handball players (mean±SD, 22.5±7.0 years, 171±7 cm, 67±7 kg) performing sidestep cutting. Three cuts from each side were analysed. Linear regression was applied between selected technique factors and maximum knee abduction moment during the first 100 ms of the contact phase. Furthermore, we investigated to what degree the abduction moment originated from the magnitude of the ground reaction force (GRF) or the knee abduction moment arm of the GRF. Technique factors explained 62% of the variance in knee abduction moments. Cut width, knee valgus, toe landing, approach speed and cutting angle were the most significant predictors. An increase in one of these factors of 1 SD increased the knee abduction moment from 12% to 19%. The effect of the moment arm of the GRF was more important than the force magnitude for maximum knee abduction moments. Lower knee abduction loads during sidestep cutting may be achieved if cuts are performed as narrow cuts with low knee valgus and toe landings. These factors may be targeted in ACL injury prevention programmes.

  7. The effect of spending cuts on teen pregnancy.

    Science.gov (United States)

    Paton, David; Wright, Liam

    2017-07-01

    In recent years, English local authorities have been forced to make significant cuts to devolved expenditure. In this paper, we examine the impact of reductions in local expenditure on one particular public health target: reducing rates of teen pregnancy. Contrary to predictions made at the time of the cuts, panel data estimates provide no evidence that areas which reduced expenditure the most have experienced relative increases in teenage pregnancy rates. Rather, expenditure cuts are associated with small reductions in teen pregnancy rates, a result which is robust to a number of alternative specifications and tests for causality. Underlying socio-economic factors such as education outcomes and alcohol consumption are found to be significant predictors of teen pregnancy. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Online Signature Verification on MOBISIG Finger-Drawn Signature Corpus

    Directory of Open Access Journals (Sweden)

    Margit Antal

    2018-01-01

    Full Text Available We present MOBISIG, a pseudosignature dataset containing finger-drawn signatures from 83 users captured with a capacitive touchscreen-based mobile device. The database was captured in three sessions resulting in 45 genuine signatures and 20 skilled forgeries for each user. The database was evaluated by two state-of-the-art methods: a function-based system using local features and a feature-based system using global features. Two types of equal error rate computations are performed: one using a global threshold and the other using user-specific thresholds. The lowest equal error rate was 0.01% against random forgeries and 5.81% against skilled forgeries using user-specific thresholds that were computed a posteriori. However, these equal error rates were significantly raised to 1.68% (random forgeries case and 14.31% (skilled forgeries case using global thresholds. The same evaluation protocol was performed on the DooDB publicly available dataset. Besides verification performance evaluations conducted on the two finger-drawn datasets, we evaluated the quality of the samples and the users of the two datasets using basic quality measures. The results show that finger-drawn signatures can be used by biometric systems with reasonable accuracy.

  9. Equilibrium Analysis in Cake Cutting

    DEFF Research Database (Denmark)

    Branzei, Simina; Miltersen, Peter Bro

    2013-01-01

    Cake cutting is a fundamental model in fair division; it represents the problem of fairly allocating a heterogeneous divisible good among agents with different preferences. The central criteria of fairness are proportionality and envy-freeness, and many of the existing protocols are designed...... of the simplest and most elegant continuous algorithms -- the Dubins-Spanier procedure, which guarantees a proportional allocation of the cake -- and study its equilibria when the agents use simple threshold strategies. We show that given a cake cutting instance with strictly positive value density functions...

  10. Finite element analysis when orthogonal cutting of hybrid composite CFRP/Ti

    Science.gov (United States)

    Xu, Jinyang; El Mansori, Mohamed

    2015-07-01

    Hybrid composite, especially CFRP/Ti stack, is usually considered as an innovative structural configuration for manufacturing the key load-bearing components in modern aerospace industry. This paper originally proposed an FE model to simulate the total chip formation process dominated the hybrid cutting operation. The hybrid composite model was established based on three physical constituents, i.e., Ti constituent, interface and CFRP constituent. Different constitutive models and damage criteria were introduced to replicate the interrelated cutting behaviour of the stack material. The CFRP/Ti interface was modelled as a third phase through the concept of cohesive zone (CZ). Particular attention was made on the comparative studies of the influence of different cutting-sequence strategies on the machining responses induced in hybrid stack cutting. The numerical results emphasized the pivotal role of cutting-sequence strategy on the various machining induced responses including cutting-force generation, machined surface quality and induced interface damage.

  11. DESIGN AND DEVELOPMENT OF SPECIAL CUTTING SYSTEM FOR SWEET SORGHUM HARVESTER

    Directory of Open Access Journals (Sweden)

    OMID GHAHRAE

    2009-03-01

    Full Text Available Sweet Sorghum is similar to racemose maize with about 3m height and 0.5-3cm thickness of stalk. Sweet Sorghum has sweet flavor stalk, which is used for sugar production. Developed cutting mechanism in this research has a rotary disk with 50 cm diameter and four cutting blades that spin clockwise. The stalks are cut with the impact and inertia forces at the linear velocity of 27 m/s, by cutting blades. This system has a simple bar mechanism guiding the whole-stalk to one side. The cutting quality tests were achieved by two series of blades with 30°and 45° blade angles on the stalk. The results showed that the stalk cutting surface with 30° blade angle was smooth and without fracture on filaments and vasculums, compared to that of 45° blade angle. Blade penetration was accomplished very well with 30° blade angle.

  12. Cutting temperature measurement and material machinability

    Directory of Open Access Journals (Sweden)

    Nedić Bogdan P.

    2014-01-01

    Full Text Available Cutting temperature is very important parameter of cutting process. Around 90% of heat generated during cutting process is then away by sawdust, and the rest is transferred to the tool and workpiece. In this research cutting temperature was measured with artificial thermocouples and question of investigation of metal machinability from aspect of cutting temperature was analyzed. For investigation of material machinability during turning artificial thermocouple was placed just below the cutting top of insert, and for drilling thermocouples were placed through screw holes on the face surface. In this way was obtained simple, reliable, economic and accurate method for investigation of cutting machinability.

  13. Plasticity, Fracture and Friction in Steady-State Plate Cutting

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Wierzbicki, Tomasz

    1997-01-01

    A closed form solution to the problem of steady-state wedge cutting through a ductile metal plate is presented. The considered problem is an idealization of a ship bottom raking process, i.e. a continuous cutting damage of a ship bottom by a hard knife-like rock in a grounding event. A new...... extension of the presented plate model to include more structural members as for example the stiffeners attached to a ship bottom plating. The fracture process is discussed and the model is formulated partly on the basis of the material fracture toughness. The effect of friction and the reaction force...... perpendicular to the direction of motion is derived theoretically in a consistent manner. The perpendicular reaction force is of paramount importance for prediction the structural damage of a ship hull because it governs the vertical ship motion and rock penetration which is strongly coupled with the horizontal...

  14. Nonlinear control of magnetic signatures

    Science.gov (United States)

    Niemoczynski, Bogdan

    Magnetic properties of ferrite structures are known to cause fluctuations in Earth's magnetic field around the object. These fluctuations are known as the object's magnetic signature and are unique based on the object's geometry and material. It is a common practice to neutralize magnetic signatures periodically after certain time intervals, however there is a growing interest to develop real time degaussing systems for various applications. Development of real time degaussing system is a challenging problem because of magnetic hysteresis and difficulties in measurement or estimation of near-field flux data. The goal of this research is to develop a real time feedback control system that can be used to minimize magnetic signatures for ferrite structures. Experimental work on controlling the magnetic signature of a cylindrical steel shell structure with a magnetic disturbance provided evidence that the control process substantially increased the interior magnetic flux. This means near field estimation using interior sensor data is likely to be inaccurate. Follow up numerical work for rectangular and cylindrical cross sections investigated variations in shell wall flux density under a variety of ambient excitation and applied disturbances. Results showed magnetic disturbances could corrupt interior sensor data and magnetic shielding due to the shell walls makes the interior very sensitive to noise. The magnetic flux inside the shell wall showed little variation due to inner disturbances and its high base value makes it less susceptible to noise. This research proceeds to describe a nonlinear controller to use the shell wall data as an input. A nonlinear plant model of magnetics is developed using a constant tau to represent domain rotation lag and a gain function k to describe the magnetic hysteresis curve for the shell wall. The model is justified by producing hysteresis curves for multiple materials, matching experimental data using a particle swarm algorithm, and

  15. Anisotropy of Single-Crystal Silicon in Nanometric Cutting.

    Science.gov (United States)

    Wang, Zhiguo; Chen, Jiaxuan; Wang, Guilian; Bai, Qingshun; Liang, Yingchun

    2017-12-01

    The anisotropy exhibited by single-crystal silicon in nanometric cutting is very significant. In order to profoundly understand the effect of crystal anisotropy on cutting behaviors, a large-scale molecular dynamics model was conducted to simulate the nanometric cutting of single-crystal silicon in the (100)[0-10], (100)[0-1-1], (110)[-110], (110)[00-1], (111)[-101], and (111)[-12-1] crystal directions in this study. The simulation results show the variations of different degrees in chip, subsurface damage, cutting force, and friction coefficient with changes in crystal plane and crystal direction. Shear deformation is the formation mechanism of subsurface damage, and the direction and complexity it forms are the primary causes that result in the anisotropy of subsurface damage. Structurally, chips could be classified into completely amorphous ones and incompletely amorphous ones containing a few crystallites. The formation mechanism of the former is high-pressure phase transformation, while the latter is obtained under the combined action of high-pressure phase transformation and cleavage. Based on an analysis of the material removal mode, it can be found that compared with the other crystal direction on the same crystal plane, the (100)[0-10], (110)[-110], and (111)[-101] directions are more suitable for ductile cutting.

  16. Finite element analyses of tool stresses in metal cutting processes

    Energy Technology Data Exchange (ETDEWEB)

    Kistler, B.L. [Sandia National Labs., Livermore, CA (United States)

    1997-01-01

    In this report, we analytically predict and examine stresses in tool tips used in high speed orthogonal machining operations. Specifically, one analysis was compared to an existing experimental measurement of stresses in a sapphire tool tip cutting 1020 steel at slow speeds. In addition, two analyses were done of a carbide tool tip in a machining process at higher cutting speeds, in order to compare to experimental results produced as part of this study. The metal being cut was simulated using a Sandia developed damage plasticity material model, which allowed the cutting to occur analytically without prespecifying the line of cutting/failure. The latter analyses incorporated temperature effects on the tool tip. Calculated tool forces and peak stresses matched experimental data to within 20%. Stress contours generally agreed between analysis and experiment. This work could be extended to investigate/predict failures in the tool tip, which would be of great interest to machining shops in understanding how to optimize cost/retooling time.

  17. Clustering by Minimum Cut Hyperplanes.

    Science.gov (United States)

    Hofmeyr, David P

    2017-08-01

    Minimum normalised graph cuts are highly effective ways of partitioning unlabeled data, having been made popular by the success of spectral clustering. This work presents a novel method for learning hyperplane separators which minimise this graph cut objective, when data are embedded in Euclidean space. The optimisation problem associated with the proposed method can be formulated as a sequence of univariate subproblems, in which the optimal hyperplane orthogonal to a given vector is determined. These subproblems can be solved in log-linear time, by exploiting the trivial factorisation of the exponential function. Experimentation suggests that the empirical runtime of the overall algorithm is also log-linear in the number of data. Asymptotic properties of the minimum cut hyperplane, both for a finite sample, and for an increasing sample assumed to arise from an underlying probability distribution are discussed. In the finite sample case the minimum cut hyperplane converges to the maximum margin hyperplane as the scaling parameter is reduced to zero. Applying the proposed methodology, both for fixed scaling, and the large margin asymptotes, is shown to produce high quality clustering models in comparison with state-of-the-art clustering algorithms in experiments using a large collection of benchmark datasets.

  18. How Can I Stop Cutting?

    Science.gov (United States)

    ... some relaxing yoga exercises Things to Help You Express the Pain and Deep Emotion Some people cut because the emotions that they ... may be hard for them to recognize these emotions for what they are — like anger, ... songs or poetry to express what you're feeling listen to music that ...

  19. Brazilian science faces swingeing cuts

    Science.gov (United States)

    Ivanissevich, Alicia

    2017-05-01

    A number of “big-science” projects in Brazil could be hit if the government pushes through a 44% cut to the R5bn (£1.28bn) budget of the Ministry of Science, Technology, Innovations and Communications (MCTIC).

  20. The Cutting-Edge Challenge

    Science.gov (United States)

    Share, Joani

    2005-01-01

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

  1. Why I like power cuts...

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Accidental power cuts - a permanent nuisance when running accelerators or computing services, since it takes a lot of time to recover from them. While I feel very sorry for those who are under pressure to get their service running again and deeply regret the loss of down-time and availability, I must admit that I like power cuts: power cuts make computers reboot! And rebooting computers at CERN means all the pending software patches are automatically applied.   But don’t think I am egotistic enough to endorse power cuts. Not necessarily! I am already happy if you regularly patch your computer(s) yourself, where regularly means at least once a month: · If you run a centrally or locally managed Windows computer, give that small orange blinking “CMF” icon in the taskbar a chance in the evening to apply all the pending patches. Also, let it initiate a reboot at the end! · If you have a personal computer with your own Windows operating system, ...

  2. Geometry of Cuts and Metrics

    NARCIS (Netherlands)

    M. Deza; M. Laurent (Monique)

    1997-01-01

    htmlabstractCuts and metrics are well-known objects that arise - independently, but with many deep and fascinating connections - in diverse fields: in graph theory, combinatorial optimization, geometry of numbers, combinatorial matrix theory, statistical physics, VLSI design etc. This book offers a

  3. Cutting and Preserving Whole Turkey

    OpenAIRE

    Brennand, Charlotte P.

    1995-01-01

    There are more uses for a turkey than roasting it whole for holiday occasions. The least expensive way to have turkey pieces, especially if the turkey is purchased on sale, is to cut it up yourself. The following is to serve as a butchering and processing guide.

  4. Wedge cutting of mild steel by CO 2 laser and cut-quality assessment in relation to normal cutting

    Science.gov (United States)

    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.

  5. Influence of Cooling Lubricants on the Surface Roughness and Energy Efficiency of the Cutting Machine Tools

    Science.gov (United States)

    Jersák, J.; Simon, S.

    2017-08-01

    The Technical University of Liberec and Brandenburg University of Technology Cottbus-Senftenberg investigated the influence of cooling lubricants on the surface roughness and energy efficiency of cutting machine tools. After summarizing the achieved experimental results, the authors conclude that cooling lubricants extensively influence the cutting temperature, cutting forces and energy consumption. Also, it is recognizable that cooling lubricants affect the cutting tools lifetime and the workpiece surface quality as well. Furthermore, costs of these cooling lubricants and the related environmental burden need to be considered. A current trend is to reduce the amount of lubricants that are used, e.g., when the Minimum Quantity Lubrication (MQL) technique is applied. The lubricant or process liquid is thereby transported by the compressed air in the form of an aerosol to the contact area between the tool and workpiece. The cutting process was monitored during testing by the three following techniques: lubricant-free cutting, cutting with the use of a lubricant with the MQL technique, and only utilizing finish-turning and finish-face milling. The research allowed the authors to monitor the cutting power and mark the achieved surface quality in relation to the electrical power consumption of the cutting machine. In conclusions, the coherence between energy efficiency of the cutting machine and the workpiece surface quality regarding the used cooling lubricant is described.

  6. Cutting efficiency of diamond burs operated with electric high-speed dental handpiece on zirconia.

    Science.gov (United States)

    Nakamura, Keisuke; Katsuda, Yusuke; Ankyu, Shuhei; Harada, Akio; Tenkumo, Taichi; Kanno, Taro; Niwano, Yoshimi; Egusa, Hiroshi; Milleding, Percy; Örtengren, Ulf

    2015-08-28

    Zirconia-based dental restorations are becoming used more commonly. However, limited attention has been given to the difficulties experienced, concerning cutting, in removing the restorations when needed. The aim of the present study was to compare the cutting efficiency of diamond burs, operated using an electric high-speed dental handpiece, on zirconia (Zir) with those on lithium disilicate glass-ceramic (LD) and leucite glass-ceramic (L). In addition, evaluation of the cutting efficiency of diamond burs on Zir of different thicknesses was performed. Specimens of Zir were prepared with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm, and specimens of LD and L were prepared with a thickness of 1.0 mm. Cutting tests were performed using diamond burs with super coarse (SC) and coarse (C) grains. The handpiece was operated at 150,000 rpm with a cutting force of 0.9 N. The results demonstrated that cutting of Zir took about 1.5- and 7-fold longer than cutting of LD and L, respectively. The SC grains showed significantly higher cutting efficiency on Zir than the C grains. However, when the thickness of Zir increased, the cutting depth was significantly decreased. As it is suggested that cutting of zirconia is time consuming, this should be taken into consideration in advance when working with zirconia restorations. © 2015 Eur J Oral Sci.

  7. A review of cutting mechanics and modeling techniques for biological materials.

    Science.gov (United States)

    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.

  8. Influence of Cooling Lubricants on the Surface Roughness and Energy Efficiency of the Cutting Machine Tools

    Directory of Open Access Journals (Sweden)

    Jersák J.

    2017-08-01

    Full Text Available The Technical University of Liberec and Brandenburg University of Technology Cottbus-Senftenberg investigated the influence of cooling lubricants on the surface roughness and energy efficiency of cutting machine tools. After summarizing the achieved experimental results, the authors conclude that cooling lubricants extensively influence the cutting temperature, cutting forces and energy consumption. Also, it is recognizable that cooling lubricants affect the cutting tools lifetime and the workpiece surface quality as well. Furthermore, costs of these cooling lubricants and the related environmental burden need to be considered. A current trend is to reduce the amount of lubricants that are used, e.g., when the Minimum Quantity Lubrication (MQL technique is applied. The lubricant or process liquid is thereby transported by the compressed air in the form of an aerosol to the contact area between the tool and workpiece. The cutting process was monitored during testing by the three following techniques: lubricant-free cutting, cutting with the use of a lubricant with the MQL technique, and only utilizing finish-turning and finish-face milling. The research allowed the authors to monitor the cutting power and mark the achieved surface quality in relation to the electrical power consumption of the cutting machine. In conclusions, the coherence between energy efficiency of the cutting machine and the workpiece surface quality regarding the used cooling lubricant is described.

  9. Time Series Based for Online Signature Verification

    Directory of Open Access Journals (Sweden)

    I Ketut Gede Darma Putra

    2013-11-01

    Full Text Available Signature verification system is to match the tested signature with a claimed signature. This paper proposes time series based for feature extraction method and dynamic time warping for match method. The system made by process of testing 900 signatures belong to 50 participants, 3 signatures for reference and 5 signatures from original user, simple imposters and trained imposters for signatures test. The final result system was tested with 50 participants with 3 references. This test obtained that system accuracy without imposters is 90,44897959% at threshold 44 with rejection errors (FNMR is 5,2% and acceptance errors (FMR is 4,35102%, when with imposters system accuracy is 80,1361% at threshold 27 with error rejection (FNMR is 15,6% and acceptance errors (average FMR is 4,263946%, with details as follows: acceptance errors is 0,391837%, acceptance errors simple imposters is 3,2% and acceptance errors trained imposters is 9,2%.

  10. Spectral signature selection for mapping unvegetated soils

    Science.gov (United States)

    May, G. A.; Petersen, G. W.

    1975-01-01

    Airborne multispectral scanner data covering the wavelength interval from 0.40-2.60 microns were collected at an altitude of 1000 m above the terrain in southeastern Pennsylvania. Uniform training areas were selected within three sites from this flightline. Soil samples were collected from each site and a procedure developed to allow assignment of scan line and element number from the multispectral scanner data to each sampling location. These soil samples were analyzed on a spectrophotometer and laboratory spectral signatures were derived. After correcting for solar radiation and atmospheric attenuation, the laboratory signatures were compared to the spectral signatures derived from these same soils using multispectral scanner data. Both signatures were used in supervised and unsupervised classification routines. Computer-generated maps using the laboratory and multispectral scanner derived signatures resulted in maps that were similar to maps resulting from field surveys. Approximately 90% agreement was obtained between classification maps produced using multispectral scanner derived signatures and laboratory derived signatures.

  11. Braking characteristics during cutting and pivoting in female soccer players.

    Science.gov (United States)

    Jones, Paul A; Herrington, Lee; Graham-Smith, Philip

    2016-10-01

    Most biomechanical studies into changing direction focus on final contact (FC), whilst limited research has examined penultimate contact (PEN). The aim of this study was to explore the kinematic and kinetic differences between PEN and FC of cutting and pivoting in 22 female soccer players (mean±SD; age: 21±3.1years, height: 1.68±0.07m, mass: 58.9±7.3kg). Furthermore, the study investigated whether horizontal force-time characteristics during PEN were related to peak knee abduction moments during FC. Three dimensional motion analyses of cutting and pivoting on the right leg were performed using Qualysis 'Proreflex' infrared cameras (240Hz). Ground reaction forces (GRF) were collected from two AMTI force platforms (1200Hz) to examine PEN and FC. Both manoeuvres involved significantly (P<0.05) greater knee joint flexion angles, peak horizontal GRF, but lower average horizontal GRF during PEN compared to FC. Average horizontal GRF during PEN (R=-0.569, R(2)=32%, P=0.006) and average horizontal GRF ratio (R=0.466, R(2)=22%, P=0.029) were significantly related to peak knee abduction moments during the FC of cutting and pivoting, respectively. The results indicate PEN during pre-planned changing direction helps reduce loading on the turning leg where there is greater risk of injuries to knee ligaments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Labor Force

    Science.gov (United States)

    Occupational Outlook Quarterly, 2012

    2012-01-01

    The labor force is the number of people ages 16 or older who are either working or looking for work. It does not include active-duty military personnel or the institutionalized population, such as prison inmates. Determining the size of the labor force is a way of determining how big the economy can get. The size of the labor force depends on two…

  13. Micro/nano-particle decorated metal wire for cutting soft matter.

    Science.gov (United States)

    Zhang, Wei; Feng, Liang-Liang; Wu, Fan; Zhang, Run-Run; Wu, Cheng-Wei

    2016-09-02

    To cut soft materials such as biological tissues with minimal damage and reduced positional error is highly desired in medical surgery and biomechanics. After years of natural selection and evolution, mosquitoes have acquired the ability to insert their proboscises into human skin with astonishingly tiny forces. This can be associated with the unique structure of their proboscises, with micro/nano sawteeth, and the distinctive insertion manner: high frequency reciprocating saw cutting. Inspired by these, this communication describes the successful implantation of metal oxide particles onto molybdenum wire surfaces through a sol-calcination process, to form a biomimetic sawblade with a high density of micro/nano saw teeth, where the acidification is essential in terms of generating active anchoring sites on the wire. When used as a sawblade in conjunction with reciprocating action to cut the viscoelastic gel, both the cut-in force and cut-in displacement could be decreased substantially. The cutting speed and frequency of reciprocating action are important operating parameters influencing cut-in force.

  14. Finite element simulation of high-speed cutting of nickel-based alloy

    Directory of Open Access Journals (Sweden)

    Yang Yong

    2016-01-01

    Full Text Available By analyzing microstructure of the material, a finite element model of high-speed cutting process more close to the practical instance was put forward. The microstructure of nickel-based alloy was obtained based SEM experiment, and the digital model of microstructure was built. Based on above study, finite element model of high-speed cutting of nickel-based alloy integrating macro and micro physical characters was established. Further, finite element simulation and analysis of high-speed cutting of nickel-based alloy were conducted, and the saw-tooth chip, cutting force variation curve and cutting temperature field distribution pictures were got. Research shows that grain boundary occur serious distortion at chip and tool contact area during saw-tooth chip forming, and the grain boundary structure changes will cause the change of cutting force during generating adiabatic shear band. So reducing cutting force and improving the processing quality can be achieved by changing the internal microscopic structure of workpiece.

  15. Cutting

    Science.gov (United States)

    ... depression, bipolar disorder , eating disorders, obsessive thinking, or compulsive behaviors. It can also be a sign of mental ... can be habit forming. It can become a compulsive behavior — meaning that the more a person does it, ...

  16. Finite element simulation of conventional and prestressed cutting of Ti6Al4V

    Science.gov (United States)

    Peng, Ruitao; Tang, Xinzi; Tan, Yuanqiang; Liu, Xiongwei

    2013-05-01

    Titanium alloys are known as difficult-to-machine materials, chip morphology plays a predominant role in determining machinability and tool wear during the machining of titanium alloys. Based on the finite element analysis and experimental validation, the cutting processes in conventional cutting and prestressed cutting of titanium alloy ring parts were explored respectively. The Johnson-Cook model expressed by equivalent plastic strain flow stress is utilized to describe the constitutive properties. A ductile fracture criterion based on the strain energy is applied to model the crack initiation and evolution during the chip segmentation. Cutting force as well as distributions of stress, temperature and equivalent plastic strain along cutting time were numerically compared. The results indicate that in conventional cutting and prestressed cutting, chips show the similar characteristic of continuous and regular serrated shape. Initial stress distribution of workpiece was changed by prestress, which correspondingly leads to the alteration of stress distribution in the subsurface layer. Prestress hardly influences the distributions of temperature and equivalent plastic strain on workpiece. The cutting force curves share the same average amplitude and analogous undulating rhythm.

  17. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  18. Infrared signatures for remote sensing

    Energy Technology Data Exchange (ETDEWEB)

    McDowell, R.S.; Sharpe, S.W.; Kelly, J.F.

    1994-04-01

    PNL`s capabilities for infrared and near-infrared spectroscopy include tunable-diode-laser (TDL) systems covering 300--3,000 cm{sup {minus}1} at <10-MHz bandwidth; a Bruker Fourier-transform infrared (FTIR) spectrometer for the near- to far-infrared at 50-MHz resolution; and a stable line-tunable, 12-w cw CO{sub 2} laser. PNL also has a beam expansion source with a 12-cm slit, which provides a 3-m effective path for gases at {approximately}10 K, giving a Doppler width of typically 10 MHz; and long-path static gas cells (to 100 m). In applying this equipment to signatures work, the authors emphasize the importance of high spectral resolution for detecting and identifying atmospheric interferences; for identifying the optimum analytical frequencies; for deriving, by spectroscopic analysis, the molecular parameters needed for modeling; and for obtaining data on species and/or bands that are not in existing databases. As an example of such spectroscopy, the authors have assigned and analyzed the C-Cl stretching region of CCl{sub 4} at 770--800 cm{sup {minus}1}. This is an important potential signature species whose IR absorption has remained puzzling because of the natural isotopic mix, extensive hot-band structure, and a Fermi resonance involving a nearby combination band. Instrument development projects include the IR sniffer, a small high-sensitivity, high-discrimination (Doppler-limited) device for fence-line or downwind monitoring that is effective even in regions of atmospheric absorption; preliminary work has achieved sensitivities at the low-ppb level. Other work covers trace species detection with TDLs, and FM-modulated CO{sub 2} laser LIDAR. The authors are planning a field experiment to interrogate the Hanford tank farm for signature species from Rattlesnake Mountain, a standoff of ca. 15 km, to be accompanied by simultaneous ground-truthing at the tanks.

  19. Water-Cut Sensor System

    KAUST Repository

    Karimi, Muhammad Akram

    2018-01-11

    Provided in some embodiments is a method of manufacturing a pipe conformable water-cut sensors system. Provided in some embodiments is method for manufacturing a water-cut sensor system that includes providing a helical T-resonator, a helical ground conductor, and a separator at an exterior of a cylindrical pipe. The helical T-resonator including a feed line, and a helical open shunt stub conductively coupled to the feed line. The helical ground conductor including a helical ground plane opposite the helical open shunt stub and a ground ring conductively coupled to the helical ground plane. The feed line overlapping at least a portion of the ground ring, and the separator disposed between the feed line and the portion of the ground ring overlapped by the feed line to electrically isolate the helical T-resonator from the helical ground conductor.

  20. The topographic signature of anthropogenic geomorphic processes

    Science.gov (United States)

    Tarolli, P.; Sofia, G.

    2014-12-01

    Within an abiotic-dominated context, geomorphologic patterns and dynamics are single expressions of trade-offs between the physical resistance forces, and the mechanical and chemical forces related to climate and erosion. Recently, however, it has become essential for the geomorphological community to take into account also biota as a fundamental geomorphologic agent acting from local to regional scales. However, while there is a recent flourishing literature about the impacts of vegetation on geomorphic processes, the study of anthropogenic pressure on geomorphology is still at its early stages. Humans are indeed among the most prominent geomorphic agents, redistributing land surface, and causing drastic changes to the geomorphic organization of the landscape (e.g. intensive agriculture, urbanization), with direct consequences on land degradation and watershed response. The reconstruction or identification of artificial or anthropogenic topographies, therefore, provides a mechanism for quantifying anthropogenic changes to the landscape systems in the context of the Anthropocene epoch. High-resolution topographic data derived from the recent remote sensing technologies (e.g. lidar, SAR, SfM), offer now new opportunities to recognize better understand geomorphic processes from topographic signatures, especially in engineered landscapes where the direct anthropic alteration of processes is significant. It is possible indeed to better recognize human-induced geomorphic and anthropogenic features (e.g. road networks, agricultural terraces), and the connected erosion. The study presented here may allow improved understanding and targeted mitigation of the processes driving geomorphic changes during urban development and help guide future research directions for development-based watershed studies. Human society is deeply affecting the environment with consequences on the landscape. It is therefore fundamental to establish greater management control over the Earth

  1. Metabolic signatures of bacterial vaginosis.

    Science.gov (United States)

    Srinivasan, Sujatha; Morgan, Martin T; Fiedler, Tina L; Djukovic, Danijel; Hoffman, Noah G; Raftery, Daniel; Marrazzo, Jeanne M; Fredricks, David N

    2015-04-14

    Bacterial vaginosis (BV) is characterized by shifts in the vaginal microbiota from Lactobacillus dominant to a microbiota with diverse anaerobic bacteria. Few studies have linked specific metabolites with bacteria found in the human vagina. Here, we report dramatic differences in metabolite compositions and concentrations associated with BV using a global metabolomics approach. We further validated important metabolites using samples from a second cohort of women and a different platform to measure metabolites. In the primary study, we compared metabolite profiles in cervicovaginal lavage fluid from 40 women with BV and 20 women without BV. Vaginal bacterial representation was determined using broad-range PCR with pyrosequencing and concentrations of bacteria by quantitative PCR. We detected 279 named biochemicals; levels of 62% of metabolites were significantly different in women with BV. Unsupervised clustering of metabolites separated women with and without BV. Women with BV have metabolite profiles marked by lower concentrations of amino acids and dipeptides, concomitant with higher levels of amino acid catabolites and polyamines. Higher levels of the signaling eicosanoid 12-hydroxyeicosatetraenoic acid (12-HETE), a biomarker for inflammation, were noted in BV. Lactobacillus crispatus and Lactobacillus jensenii exhibited similar metabolite correlation patterns, which were distinct from correlation patterns exhibited by BV-associated bacteria. Several metabolites were significantly associated with clinical signs and symptoms (Amsel criteria) used to diagnose BV, and no metabolite was associated with all four clinical criteria. BV has strong metabolic signatures across multiple metabolic pathways, and these signatures are associated with the presence and concentrations of particular bacteria. Bacterial vaginosis (BV) is a common but highly enigmatic condition that is associated with adverse outcomes for women and their neonates. Small molecule metabolites in the

  2. Variability of grip kinetics during adult signature writing.

    Directory of Open Access Journals (Sweden)

    Bassma Ghali

    Full Text Available Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20 adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of 1.2±0.4% in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.

  3. Analysis of forces in ultrasonically assisted turning

    Science.gov (United States)

    Ahmed, N.; Mitrofanov, A. V.; Babitsky, V. I.; Silberschmidt, V. V.

    2007-12-01

    Many modern engineering materials are very difficult to process with conventional machining methods. Ultrasonically assisted turning (UAT) is a new technology, where high frequency vibration (frequency f≈20 kHz, amplitude a≈15 μm) is superimposed on the movement of the cutting tool. Compared to conventional turning (CT), UAT allows significant improvements in processing many intractable materials, such as high-strength aerospace alloys and composites, by producing a noticeable decrease in cutting forces and a superior surface finish. Vibro-impact interaction between the tool and workpiece in UAT during the chip formation leads to a dynamically changing cutting force in the process zone as compared to the quasistatic one in CT. The paper presents an experimental study and computational (finite-element) model of both CT and UAT. Forces acting on the cutting tool in UAT are studied, and their dependence on vibration amplitude, frequency and vibration direction as well as on cutting parameters, such as feed rate and cutting speed, are investigated.

  4. Study on Burr Formation at the Top Edge in Rectangular Groove Cutting

    Directory of Open Access Journals (Sweden)

    Wen Jun Deng

    2012-01-01

    Full Text Available Previous research on burr formation in machining operations has usually been limited to the study of the rollover burr in the cutting direction. In this paper, a 3D finite element model to simulate rectangular groove cutting operation has been developed using commercial finite element software, employing experimentally determined mechanical properties at elevated strain rates and temperatures. The plastic deformation behavior and three-dimensional burr formation during rectangular groove cutting is investigated. The simulated burr profile and cutting force prove that the developed model can capture the thermo-mechanical mechanisms in rectangular groove cutting and can simulate burr development with considerable accuracy. The study concentrates on the influence of cutting parameters on burr formation which are also conducted. The results show that the feed rate and rake angle are the cutting parameters which have a major influence on burr size in the groove cutting operation. And the effect of cutting velocity and minor clearance angle in the traditional range on burr size are quite limited.

  5. Computer-aided analysis of cutting processes for brittle materials

    Science.gov (United States)

    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.

  6. Method of cutting radioactivated metal structures

    International Nuclear Information System (INIS)

    Takimoto, Yoshinori; Sakota, Kotaro; Hamamoto, Noboru; Harada, Keizo.

    1985-01-01

    Purpose: To improve the cutting performance to a level as comparable with that in air, as well as prevent the scattering of the radioactive materials upon cutting to the level as that in water cutting. Method: After igniting a gas cutting torch automatically, water spray by the local water sprayer is started by the actuation of a submerged pump, while a gas cutting manipulator is operated to cut the nuclear reactor pressure vessel. In this way, cutting exhaust gases resulted from the gas cutting torch are water-washed by the spray from the local water sprayer and falls within the nuclear rector pressure vessel in the form of water streams or droplets along the inner wall surface of the pressure vessel. Further, water is fed again to the local water sprayer by the submerged pump. (Kawakami, Y.)

  7. European labs fight back against cuts

    CERN Multimedia

    König, R

    1997-01-01

    Germany's 1997 budget contains cuts amounting to 3.7% in funding of domestic research programs and in contributions to international labs. Contributions will be cut to the European Space Agency, the European Synchrotron facility and CERN.

  8. Mono-jet signatures of gluphilic scalar dark matter

    Directory of Open Access Journals (Sweden)

    Rohini M. Godbole

    2017-09-01

    Full Text Available A gluphilic scalar dark matter (GSDM model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum (“mono-jet” in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT treatment, and find (as expected that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3 representation of the mediator from the s=8 TeV data, and show the expected reach of the s=13 TeV LHC and a future 100 TeV pp collider to constrain or discover GSDM models.

  9. Search for Supersymmetry in a Three Lepton Plus Jets Signature

    CERN Document Server

    Zarzhitsky, Pavel; Kehoe, Robert; Stroynowski, Ryszard

    We present a search for three lepton plus jets supersymmetric signal at ATLAS detector, LHC, at sqrt(s)=14 TeV. The signal signature must contain three isolated leptons with pT's above 5 GeV and two jets with pT's above 40 GeV. The leptons must form a same or opposite charge pair. The analysis was done using the Monte Carlo data equivalent to 1 fb-1 of the real data. tt, WZ, Zbb and Z+jets processes were considered as backgrounds. The signal extraction from the backgrounds was done using optimization cuts in five variables: pT's of leptons, HT and missing ET. It was shown that the statistical significance = S/(S+B)=6:3 for 1 fb-1. This allows an early SUSY discovery. The discovery limit = 5 sigma can be reached at 650 pb-1. The effect of the main jet calibration uncertainty determined to be small.

  10. Theoretical Characterizaiton of Visual Signatures

    Science.gov (United States)

    Kashinski, D. O.; Chase, G. M.; di Nallo, O. E.; Scales, A. N.; Vanderley, D. L.; Byrd, E. F. C.

    2015-05-01

    We are investigating the accuracy of theoretical models used to predict the visible, ultraviolet, and infrared spectra, as well as other properties, of product materials ejected from the muzzle of currently fielded systems. Recent advances in solid propellants has made the management of muzzle signature (flash) a principle issue in weapons development across the calibers. A priori prediction of the electromagnetic spectra of formulations will allow researchers to tailor blends that yield desired signatures and determine spectrographic detection ranges. Quantum chemistry methods at various levels of sophistication have been employed to optimize molecular geometries, compute unscaled vibrational frequencies, and determine the optical spectra of specific gas-phase species. Electronic excitations are being computed using Time Dependent Density Functional Theory (TD-DFT). A full statistical analysis and reliability assessment of computational results is currently underway. A comparison of theoretical results to experimental values found in the literature is used to assess any affects of functional choice and basis set on calculation accuracy. The status of this work will be presented at the conference. Work supported by the ARL, DoD HPCMP, and USMA.

  11. Characterization of vibratory turning in cutting zone using a pneumatic quick-stop device

    Directory of Open Access Journals (Sweden)

    Saeid Amini

    2017-04-01

    Full Text Available Shear angle and sticking length are two crucial parameters in mechanics of metal cutting. These two parameters directly influence machinability factors such as cutting forces. Thus, shear angle and sticking length were investigated in vibratory turning process by using a pneumatic quick-stop device which was designed and fabricated, in this study. After preparation of ultrasonic assisted turning set-up, experimental tests have been carried out on two types of steel: AISI-1060 and AISI 304. Accordingly, the process of chip formation in each particular cutting test was quickly stopped when deformed chip was still in contact with workpiece. As a result, it was revealed that added linear vibration leads the turning operation to be improved by increase of shear angle and decrease of sticking length. Moreover, the effect of ultrasonic vibration on cutting force and chip micro-hardness is evaluated.

  12. Effect of microstructure and cutting speed on machining behavior of Ti6Al4V alloy

    Energy Technology Data Exchange (ETDEWEB)

    Telrandhe, Sagar V.; Mishra, Sushil; Saxena, Ashish K. [Indian Institute of Technology Bombay, Mumbai (India)

    2017-05-15

    Machining of aerospace and biomedical grade titanium alloys has always been a challenge because of their low conductivity and elastic modulus. Different machining methods and parameters have been adopted for high precision machining of titanium alloys. Machining of titanium alloys can be improved by microstructure optimization. The present study focuses on the effect of microstructure on ma- chinability of Ti6Al4V alloys at different cutting speeds. Samples were subjected to different annealing conditions resulting in different grain sizes and local micro-strains (misorientation). Cutting forces were significantly reduced after annealing; consequently, sub-surface residual stresses were reduced. Deformation twinning was also observed on samples annealed at a higher temperature due to larger grain size. Initial strain free grains and deformation twinning during machining reduces the cutting force at higher cutting speed.

  13. Forced marriage.

    Science.gov (United States)

    2007-06-01

    Guidelines to help A&E staff and other healthcare professionals who suspect cases of forced marriage were launched this month by the government. The guidelines provide practical advice on how to recognise the warning signs, and what to do if patients disclose that they have been, or are about to be, forced to marry. The guidelines, Dealing with Cases of Forced Marriage, are available at www.fco.gov.uk/forcedmarriage.

  14. Effects of heat on cut mark characteristics.

    OpenAIRE

    Waltenberger, L.; Schutkowski, Holger

    2017-01-01

    Cut marks on bones provide crucial information about tools used and their mode of application, both in archaeological and forensic contexts. Despite a substantial amount of research on cut mark analysis and the influence of fire on bones (shrinkage, fracture pattern, recrystallisation), there is still a lack of knowledge in cut mark analysis on burnt remains. This study provides information about heat alteration of cut marks and whether consistent features can be observed that allow direct in...

  15. Intrusion signature creation via clustering anomalies

    Science.gov (United States)

    Hendry, Gilbert R.; Yang, Shanchieh J.

    2008-03-01

    Current practices for combating cyber attacks typically use Intrusion Detection Systems (IDSs) to detect and block multistage attacks. Because of the speed and impacts of new types of cyber attacks, current IDSs are limited in providing accurate detection while reliably adapting to new attacks. In signature-based IDS systems, this limitation is made apparent by the latency from day zero of an attack to the creation of an appropriate signature. This work hypothesizes that this latency can be shortened by creating signatures via anomaly-based algorithms. A hybrid supervised and unsupervised clustering algorithm is proposed for new signature creation. These new signatures created in real-time would take effect immediately, ideally detecting new attacks. This work first investigates a modified density-based clustering algorithm as an IDS, with its strengths and weaknesses identified. A signature creation algorithm leveraging the summarizing abilities of clustering is investigated. Lessons learned from the supervised signature creation are then leveraged for the development of unsupervised real-time signature classification. Automating signature creation and classification via clustering is demonstrated as satisfactory but with limitations.

  16. On reliable discovery of molecular signatures

    Directory of Open Access Journals (Sweden)

    Björkegren Johan

    2009-01-01

    Full Text Available Abstract Background Molecular signatures are sets of genes, proteins, genetic variants or other variables that can be used as markers for a particular phenotype. Reliable signature discovery methods could yield valuable insight into cell biology and mechanisms of human disease. However, it is currently not clear how to control error rates such as the false discovery rate (FDR in signature discovery. Moreover, signatures for cancer gene expression have been shown to be unstable, that is, difficult to replicate in independent studies, casting doubts on their reliability. Results We demonstrate that with modern prediction methods, signatures that yield accurate predictions may still have a high FDR. Further, we show that even signatures with low FDR may fail to replicate in independent studies due to limited statistical power. Thus, neither stability nor predictive accuracy are relevant when FDR control is the primary goal. We therefore develop a general statistical hypothesis testing framework that for the first time provides FDR control for signature discovery. Our method is demonstrated to be correct in simulation studies. When applied to five cancer data sets, the method was able to discover molecular signatures with 5% FDR in three cases, while two data sets yielded no significant findings. Conclusion Our approach enables reliable discovery of molecular signatures from genome-wide data with current sample sizes. The statistical framework developed herein is potentially applicable to a wide range of prediction problems in bioinformatics.

  17. An Arbitrated Quantum Signature Scheme without Entanglement"*

    International Nuclear Information System (INIS)

    Li Hui-Ran; Luo Ming-Xing; Peng Dai-Yuan; Wang Xiao-Jun

    2017-01-01

    Several quantum signature schemes are recently proposed to realize secure signatures of quantum or classical messages. Arbitrated quantum signature as one nontrivial scheme has attracted great interests because of its usefulness and efficiency. Unfortunately, previous schemes cannot against Trojan horse attack and DoS attack and lack of the unforgeability and the non-repudiation. In this paper, we propose an improved arbitrated quantum signature to address these secure issues with the honesty arbitrator. Our scheme takes use of qubit states not entanglements. More importantly, the qubit scheme can achieve the unforgeability and the non-repudiation. Our scheme is also secure for other known quantum attacks . (paper)

  18. An Arbitrated Quantum Signature Scheme without Entanglement*

    Science.gov (United States)

    Li, Hui-Ran; Luo, Ming-Xing; Peng, Dai-Yuan; Wang, Xiao-Jun

    2017-09-01

    Several quantum signature schemes are recently proposed to realize secure signatures of quantum or classical messages. Arbitrated quantum signature as one nontrivial scheme has attracted great interests because of its usefulness and efficiency. Unfortunately, previous schemes cannot against Trojan horse attack and DoS attack and lack of the unforgeability and the non-repudiation. In this paper, we propose an improved arbitrated quantum signature to address these secure issues with the honesty arbitrator. Our scheme takes use of qubit states not entanglements. More importantly, the qubit scheme can achieve the unforgeability and the non-repudiation. Our scheme is also secure for other known quantum attacks.

  19. The size effect in metal cutting

    Indian Academy of Sciences (India)

    and when the size of the material removed decreases, the probability of encountering a stress-reducing defect decreases. Since the shear stress and strain in metal cutting is unusually high, discontinuous microcracks usually form on the metal-cutting shear plane. If the material being cut is very brittle, or the compressive ...

  20. Simulation of stationary sheet metal cutting processes

    NARCIS (Netherlands)

    Wisselink, H.H.; Huetink, Han

    1998-01-01

    In stationary sheet metal cutting processes, like guillotining and slitting, the sheet is cut progressively from one end to the other. This in contrary with transient processes (blanking) where the sheet is cut at once. Where transient shearing processes can be modelled in 2-D (plain strain or

  1. Air in xylem vessels of cut flowers

    NARCIS (Netherlands)

    Nijsse, J.; Meeteren, van U.; Keijzer, C.J.

    2000-01-01

    Until now all studies on the role of air emboli in the water uptake of cut flowers describe indirect methods to demonstrate the presencFe of air in the plant tissues. Using cut chrysanthemum flowers, this report is the first one that directly visualises both air and water in xylem ducts of cut

  2. The size effect in metal cutting

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    stress and strain in metal cutting is unusually high, discontinuous microcracks usually form on the metal-cutting shear plane. If the material being cut is very brittle, or the compressive stress on the shear plane is relatively low, microcracks grow into gross cracks giving rise to discontinuous chip formation. When discontinuous.

  3. Impact of Grinding Wheel Position on Flute Profile of End mill and Cutting Process

    Science.gov (United States)

    Zhidyaev, Alexey N.

    2018-01-01

    The article provides the research on flute profile of end mills. The flute profile of a specified end mill design is affected by grinding wheel position relative to end mill workpiece in grinding operation. Different profiles were obtained, their rake surfaces and cross section areas were compared. Temperatures and cutting forces were evaluated via finite element analysis for these profiles in case of titanium alloy and heat-resistant alloy machining. Finally, the impact of flute profile on cutting process was assessed.

  4. Prediction of Cutting Tool Life in Drilling of Reinforced Aluminum Alloy Composite Using a Fuzzy Method

    OpenAIRE

    Mohammed T. Hayajneh

    2016-01-01

    Machining of Metal Matrix Composites (MMCs) is very significant process and has been a main problem that draws many researchers to investigate the characteristics of MMCs during different machining process. The poor machining properties of hard particles reinforced MMCs make drilling process a rather interesting task. Unlike drilling of conventional materials, many problems can be seriously encountered during drilling of MMCs, such as tool wear and cutting forces. Cutting tool wear is a very ...

  5. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    Science.gov (United States)

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Modelling infrared signatures of ships and decoys for countermeasure effectiveness studies

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Degache, M.A.C.; Veerman, H.E.T.; Sweeden, R. van; Devecchi, B.A.

    2012-01-01

    Infrared guided missiles are a threat for modern naval forces. The vulnerability of ships can be reduced by applying countermeasures such as infrared decoys and infrared signature reduction. This paper presents recent improvements in a simulation toolset which can be used for assessing the

  7. Evaluation tools for the effectiveness of infrared countermeasures and signature reduction for ships

    NARCIS (Netherlands)

    Schoemaker, R.M.; Schleijpen, H.M.A.

    2010-01-01

    The protection of ships against infrared guided missiles is a concern for modern naval forces. The vulnerability of ships can be reduced by applying countermeasures such as infrared decoys and infrared signature reduction. This paper will present a set of simulation tools which can be used for

  8. Monte Carlo study of holding forces for tank cars on grades

    Science.gov (United States)

    2013-04-15

    This paper describes a numerical procedure to examine the holding forces needed to secure a cut of railroad tank cars staged on a grade during loading and unloading operations. Holding forces are created by applying emergency brake systems and blocki...

  9. Anvil microphysical signatures associated with lightning-produced NOx

    Directory of Open Access Journals (Sweden)

    J. L. Stith

    2016-02-01

    Full Text Available Thunderstorm anvils were studied during the Deep Convective Clouds and Chemistry experiment (DC3, using in situ measurements and observations of ice particles and NOx together with radar and Lightning Mapping Array measurements. A characteristic ice particle and NOx signature was found in the anvils from three storms, each containing high lightning flash rates in the storm core prior to anvil sampling. This signature exhibits high concentrations of frozen droplets (as measured by a Cloud Droplet Probe coincident with lower NOx on the edges of the anvil. The central portion of these anvils exhibited a high degree of aggregation of these frozen droplets and higher levels of NOx. In contrast, a deep convective cell with low lightning flash rates had high concentrations of both frozen droplets and aggregated frozen droplets in its anvil's central region. A conceptual model for these results is presented and applied to the observations from each of these storms. High NOx concentrations are often found where aggregation of frozen droplets has occurred, which may be a reflection of aggregation by electrical forces in the regions where lightning is occurring, although the level of NOx for a given concentration of aggregates varies from storm to storm. These observations between anvil microphysics and lightning and/or NOx signatures suggest that lightning data may be an important tool to characterize or infer the microphysical, radiative, and chemical properties of thunderstorm anvils.

  10. Tau-Sneutrino NLSP and Multilepton Signatures at the LHC

    CERN Document Server

    Figy, Terrance; Santoso, Yudi

    2010-01-01

    In models with gravitino as the lightest supersymmetric particle(LSP), the next to lightest supersymmetric particle (NLSP) can have a long lifetime and appear stable in collider experiments. We study the leptonic signatures of such a scenario with tau-sneutrino as the NLSP, which is realized in the non-universal Higgs masses scenario. We focus on an interesting trilepton signature with two like-sign taus and an electron or a muon of opposite sign. The neutralinos and charginos are quite heavy in the model considered, and the trilepton signal comes mostly from the slepton-sneutrino production. We identify the relevant backgrounds, taking into account tau decays, and devise a set of cuts to optimize this trilepton signal. We simulate signal and backgrounds at the LHC with 14 TeV center-of-mass energy. Although the sleptons in this model are relatively light, O(100 GeV), discovery is more demanding compared to typical neutralino LSP scenarios. The trilepton signal requires large amount of accumulated data, at le...

  11. Different forces

    CERN Multimedia

    1982-01-01

    The different forces, together with a pictorial analogy of how the exchange of particles works. The table lists the relative strength of the couplings, the quanta associated with the force fields and the bodies or phenomena in which they have a dominant role.

  12. Characterisation of Fracture Behaviour of Starch Gels Using Conventional Fracture Mechanics and Wire Cutting Tests

    Science.gov (United States)

    Gamonpilas, C.; Charalambides, M. N.; Williams, J. G.; Dooling, P. J.; Gibbon, S. R.

    2008-07-01

    The fracture behaviour of starch gels is investigated through experimental tests and finite element simulations. Both conventional fracture and wire cutting experiments were performed. The results from these two tests were consistent with the fracture toughness increasing with loading rate. In the FE analysis, a non-linear elastic constitutive relationship was used to model the starch gels and frictionless condition was assumed between the wire-starch gel contact interface. A failure criterion based on critical fracture strain was assumed. Predictions of the steady-state cutting force at various wire diameters were found to be in good agreement with the wire cutting data.

  13. Experiment on Conical Pick Cutting Rock Material Assisted with Front and Rear Water Jet

    Directory of Open Access Journals (Sweden)

    Xiaohui Liu

    2015-01-01

    Full Text Available Conical picks are one kind of cutting tools widely used in engineering machinery. In the process of rock breaking, the conical pick bears great cutting force and wear. To solve the problem, a new method, conical pick assisted with high pressure water jet, could break rock effectively, and four different configuration modes of water jet were presented. In this paper, based on the analysis of the different water jet configuration’s advantages and disadvantages, experiments on front water jet, new typed rear water jet, and the combination of those two water jet configuration modes were conducted to study the assisting cutting performance and obtain the quantitative results.

  14. Molecular dynamic simulation for nanometric cutting of single-crystal face-centered cubic metals.

    Science.gov (United States)

    Huang, Yanhua; Zong, Wenjun

    2014-01-01

    In this work, molecular dynamics simulations are performed to investigate the influence of material properties on the nanometric cutting of single crystal copper and aluminum with a diamond cutting tool. The atomic interactions in the two metallic materials are modeled by two sets of embedded atom method (EAM) potential parameters. Simulation results show that although the plastic deformation of the two materials is achieved by dislocation activities, the deformation behavior and related physical phenomena, such as the machining forces, machined surface quality, and chip morphology, are significantly different for different materials. Furthermore, the influence of material properties on the nanometric cutting has a strong dependence on the operating temperature.

  15. Free-piston cutting machine

    Science.gov (United States)

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

    2000-01-01

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

  16. PHYSICAL-MATEMATICALSCIENCE MECHANICS SIMULATION CHALLENGES IN OPTIMISING THEORETICAL METAL CUTTING TASKS

    Directory of Open Access Journals (Sweden)

    Rasul V. Guseynov

    2017-01-01

    Full Text Available Abstract. Objectives In the article, problems in the optimising of machining operations, which provide end-unit production of the required quality with a minimum processing cost, are addressed. Methods Increasing the effectiveness of experimental research was achieved through the use of mathematical methods for planning experiments for optimising metal cutting tasks. The minimal processing cost model, in which the objective function is polynomial, is adopted as a criterion for the selection of optimal parameters. Results Polynomial models of the influence of angles φ, α, γ on the torque applied when cutting threads in various steels are constructed. Optimum values of the geometrical tool parameters were obtained using the criterion of minimum cutting forces during processing. The high stability of tools having optimal geometric parameters is determined. It is shown that the use of experimental planning methods allows the optimisation of cutting parameters. In optimising solutions to metal cutting problems, it is found to be expedient to use multifactor experimental planning methods and to select the cutting force as the optimisation parameter when determining tool geometry. Conclusion The joint use of geometric programming and experiment planning methods in order to optimise the parameters of cutting significantly increases the efficiency of technological metal processing approaches. 

  17. Smart Cutting Tools and Smart Machining: Development Approaches, and Their Implementation and Application Perspectives

    Science.gov (United States)

    Cheng, Kai; Niu, Zhi-Chao; Wang, Robin C.; Rakowski, Richard; Bateman, Richard

    2017-09-01

    Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultraprecision and micro manufacturing purposes. Implementation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation techniques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algorithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in-process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) application exemplars on adaptive smart machining.

  18. Laser Cutting of Carbon Fiber Fabrics

    Science.gov (United States)

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

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

  19. Signature spectrale des grains interstellaires.

    Science.gov (United States)

    Léger, A.

    Notre connaissance de la nature des grains interstellaires reposait sur un nombre très restreint de signatures spectrales dans la courbe d'extinction du milieu interstellaire. Une information considérable est contenue dans les 40 bandes interstellaires diffuses dans le visible, mais reste inexploitée. L'interprétation récente des cinq bandes IR en émission, en terme de molécules d'hydrocarbures aromatiques polycycliques, est développée. Elle permet l'utilisation d'une information spectroscopique comparable, à elle seule, à ce sur quoi était basée jusqu'alors notre connaissance de la matière interstellaire condensée. Différentes implications de cette mise en évidence sont proposées.

  20. Rooting of stem cuttings of ixora

    Directory of Open Access Journals (Sweden)

    Aline De Souza Silva

    2015-08-01

    Full Text Available The ixora is ornamental plant widely used in landscaping. In order to maximize the propagation of cuts, we evaluated the concentrations of auxin (indolbutiric acid and the presence of leaves on the rooting in cuts of Ixora coccinea L. The experiment was conducted in randomized block design, in factorial design 3x4, with three types of cuts (without leaf, with two or four leaves, four concentrations of indolbutiric acid (0, 1000, 2000 and 4000 mg L-1, with four replications and 10 cuts in each experimental unit. After 53 days of implantation the experiment, evaluated the survival(%, rooting(%, sprouting(%, formation of callus(%, number, length and biomass of roots formed. The interaction of the type of cuts with concentrations of auxin was not significant for any of the variables analyzed. The survival of cuttings was not influenced by the treatments. Cuts with two or four leaves presented rooting and length of roots above the cuttings without leaves. The application of auxin does not substitute the presence of leaf in cuts of ixora in vegetative propagation. The vegetative propagation by cut of ixora can be made without application of auxin, and the leaves must be maintained in the cuttings.

  1. Research of cutting power with cutting chipboards with different properties by circular saw

    Directory of Open Access Journals (Sweden)

    Stanojević Damjan M.

    2015-01-01

    Full Text Available In this paper elaborates the process of measuring cutting power which occurred during cutting six types of particle board. Chipboards with different physical and mechanical properties were cut in order to find some correlation with the cutting power ie to be able to determine the effect of moisture, density and bending strength of the plate to the cutting power. Measuring power cut was made in the workshop of the Faculty of Forestry, Belgrade, measuring the moisture and density in the laboratory for testing particle board, and the bending strength was performed in the laboratory for testing the properties of wood. During the cutting speed are changed auxiliary movements to determine the influence of the machining parameters on cutting power. Overall, it was concluded that with increasing moisture content of the work-piece cutting power decreases with increasing velocity displacement, density and bending strength of the board, required cutting power increases.

  2. Cutting method and cutting device for spent fuel rod of nuclear reactor

    International Nuclear Information System (INIS)

    Komatsu, Masahiko; Ose, Toshihiko.

    1996-01-01

    A control rod transferred under water in a vertically suspended state is postured horizontally at such a water depth that radiations can be shielded, and then it is cut to a dropping speed limiting portion and a cross-like main body. The separated cross-like main body portion is further cut in the longitudinal direction and separated into a pair of cut pieces each having an L-shaped cross section. A disk like metal saw is used as a cutting tool. Alternatively, a plasma jet cutter or a melting-type water jet cutter is used as a cutting tool. Then, since the spent control rod to be cut is postured horizontally under water, the water depth for the cutting position can be reduced. As a result, the cutting state using the cutting tool can be observed by naked eyes from the position above the water surface thereby enabling to perform the cutting operation reliably. (N.H.)

  3. Effect of feed rate, workpiece hardness and cutting edge on subsurface residual stress in the hard turning of bearing steel using chamfer + hone cutting edge geometry

    International Nuclear Information System (INIS)

    Hua Jiang; Shivpuri, Rajiv; Cheng Xiaomin; Bedekar, Vikram; Matsumoto, Yoichi; Hashimoto, Fukuo; Watkins, Thomas R.

    2005-01-01

    Residual stress on the machined surface and the subsurface is known to influence the service quality of a component, such as fatigue life, tribological properties, and distortion. Therefore, it is essential to predict and control it for enhanced performance. In this paper, a newly proposed hardness based flow stress model is incorporated into an elastic-viscoplastic finite element model of hard turning to analyze process variables that affect the residual stress profile of the machined surface. The effects of cutting edge geometry and workpiece hardness as well as cutting conditions, such as feed rate and cutting speed, are investigated. Numerical analysis shows that hone edge plus chamfer cutting edge and aggressive feed rate help to increase both compressive residual stress and penetration depth. These predictions are validated by face turning experiments which were conducted using a chamfer with hone cutting edge for different material hardness and cutting parameters. The residual stresses under the machined surface are measured by X-ray diffraction/electropolishing method. A maximum circumferential residual stress of about 1700 MPa at a depth of 40 μm is reached for hardness of 62 HRc and feed rate of 0.56 mm/rev. This represents a significant increase from previously reported results in literatures. It is found from this analysis that using medium hone radius (0.02-0.05 mm) plus chamfer is good for keeping tool temperature and cutting force low, while obtaining desired residual stress profile

  4. The center-cut solution.

    Science.gov (United States)

    Firnstahl, T W

    1993-01-01

    Timothy Firnstahl owns five successful restaurants in Seattle, but he recently came very close to owning none. In the early 1990s, he found himself, like so many restauranteurs, facing rising costs, inefficient management, and a recession. Confronting financial annihilation, Firnstahl had to act quickly: since he had no peripherals to trim, he cut off the head of his company. Remarkably, it worked. Firnstahl's problem was his new and innovative restaurant, Sharps Fresh Roasting. The heart of the Sharps concept was a unique long-roasting technique that made lean, inexpensive meats taste as juicy and delicious as fattier, expensive cuts. The process also lent itself to faster service and lower labor costs. But it wasn't working. Sharps wasn't breaking even, and his other restaurants couldn't make up the difference. He needed a solution fast. Firnstahl got his answer from Mikhail Gorbachev: slash the centralized command and liberate the company. In doing so, he would also transfer virtually all power and responsibility to his line managers. And after five months of intensive study and planning, he accomplished what he set out to do. He fired most of his corporate staff, empowered his restaurant managers with "100% Power and Responsibility," and, finally, undertook a massive promotion campaign. A year later, Sharps Fresh Roasting is the gold mine Firnstahl always believed it could be. He's done away with bureaucracy and turned business around in a down market. All this because his managers are managing themselves.

  5. Prediction of soil effects on GPR signatures

    NARCIS (Netherlands)

    Rhebergen, J.B.; Lensen, H.A.; Wijk, C.V. van; Hendrickx, J.M.H.; Dam, R. van; Borchers, B.

    2004-01-01

    In previous work we have shown that GPR signatures are affected by soil texture and soil water content. In this contribution we will use a three dimensional electromagnetic model and a hydrological soil model to explore in more detail the relationships between GPR signatures, soil physical

  6. Measuring ship acoustic signatures against mine threat

    NARCIS (Netherlands)

    Jong, C.A.F. de; Quesson, B.A.J.; Ainslie, M.A.; Vermeulen, R.C.N.

    2012-01-01

    The NATO standard ‘AMP-15’ [1] provides procedures for the measurement and reporting of the acoustic signature of ships and for the establishment of acoustic signature goals to counter the naval mine threat. Measurements are carried out at dedicated shallow water acoustic ranges. Measurements

  7. The Pedagogic Signature of the Teaching Profession

    Science.gov (United States)

    Kiel, Ewald; Lerche, Thomas; Kollmannsberger, Markus; Oubaid, Viktor; Weiss, Sabine

    2016-01-01

    Lee S. Shulman deplores that the field of education as a profession does not have a pedagogic signature, which he characterizes as a synthesis of cognitive, practical and moral apprenticeship. In this context, the following study has three goals: 1) In the first theoretical part, the basic problems of constructing a pedagogic signature are…

  8. Infrared ship signature analysis and optimisation

    NARCIS (Netherlands)

    Neele, F.P.

    2005-01-01

    The last decade has seen an increase in the awareness of the infrared signature of naval ships. New ship designs show that infrared signature reduction measures are being incorporated, such as exhaust gas cooling systems, relocation of the exhausts and surface cooling systems. Hull and

  9. Quantum signature scheme for known quantum messages

    International Nuclear Information System (INIS)

    Kim, Taewan; Lee, Hyang-Sook

    2015-01-01

    When we want to sign a quantum message that we create, we can use arbitrated quantum signature schemes which are possible to sign for not only known quantum messages but also unknown quantum messages. However, since the arbitrated quantum signature schemes need the help of a trusted arbitrator in each verification of the signature, it is known that the schemes are not convenient in practical use. If we consider only known quantum messages such as the above situation, there can exist a quantum signature scheme with more efficient structure. In this paper, we present a new quantum signature scheme for known quantum messages without the help of an arbitrator. Differing from arbitrated quantum signature schemes based on the quantum one-time pad with the symmetric key, since our scheme is based on quantum public-key cryptosystems, the validity of the signature can be verified by a receiver without the help of an arbitrator. Moreover, we show that our scheme provides the functions of quantum message integrity, user authentication and non-repudiation of the origin as in digital signature schemes. (paper)

  10. Analysis of signature wrapping attacks and countermeasures

    DEFF Research Database (Denmark)

    Gajek, Sebastian; Jensen, Meiko; Liao, Lijun

    2009-01-01

    In recent research it turned out that Boolean verification, of digital signatures in the context of WSSecurity, is likely to fail: If parts of a SOAP message, are signed and the signature verification applied to, the whole document returns true, then nevertheless the, document may have been...

  11. Real time gamma-ray signature identifier

    Science.gov (United States)

    Rowland, Mark [Alamo, CA; Gosnell, Tom B [Moraga, CA; Ham, Cheryl [Livermore, CA; Perkins, Dwight [Livermore, CA; Wong, James [Dublin, CA

    2012-05-15

    A real time gamma-ray signature/source identification method and system using principal components analysis (PCA) for transforming and substantially reducing one or more comprehensive spectral libraries of nuclear materials types and configurations into a corresponding concise representation/signature(s) representing and indexing each individual predetermined spectrum in principal component (PC) space, wherein an unknown gamma-ray signature may be compared against the representative signature to find a match or at least characterize the unknown signature from among all the entries in the library with a single regression or simple projection into the PC space, so as to substantially reduce processing time and computing resources and enable real-time characterization and/or identification.

  12. Redactable signatures for signed CDA Documents.

    Science.gov (United States)

    Wu, Zhen-Yu; Hsueh, Chih-Wen; Tsai, Cheng-Yu; Lai, Feipei; Lee, Hung-Chang; Chung, Yufang

    2012-06-01

    The Clinical Document Architecture, introduced by Health Level Seven, is a XML-based standard intending to specify the encoding, structure, and semantics of clinical documents for exchange. Since the clinical document is in XML form, its authenticity and integrity could be guaranteed by the use of the XML signature published by W3C. While a clinical document wants to conceal some personal or private information, the document needs to be redacted. It makes the signed signature of the original clinical document not be verified. The redactable signature is thus proposed to enable verification for the redacted document. Only a little research does the implementation of the redactable signature, and there still not exists an appropriate scheme for the clinical document. This paper will investigate the existing web-technologies and find a compact and applicable model to implement a suitable redactable signature for the clinical document viewer.

  13. Human topographic signatures and derived geomorphic processes across landscapes

    Science.gov (United States)

    Tarolli, Paolo; Sofia, Giulia

    2016-02-01

    The Earth's surface morphology, in an abiotic context, is a consequence of major forcings such as tectonic uplift, erosion, sediment transport, and climate. Recently, however, it has become essential for the geomorphological community to also take into account biota as a geomorphological agent that has a role in shaping the landscape, even if at a different scale and magnitude from that of geology. Although the modern literature is flourishing on the impacts of vegetation on geomorphic processes, the study of anthropogenic pressures on geomorphology is still in its early stages. Topography emerges as a result of natural driving forces, but some human activities (such as mining, agricultural practices and the construction of road networks) directly or indirectly move large quantities of soil, which leave clear topographic signatures embedded on the Earth's morphology. These signatures can cause drastic changes to the geomorphological organization of the landscape, with direct consequences on Earth surface processes. This review provides an overview of the recent literature on the role of humans as a geological agent in shaping the morphology of the landscape. We explore different contexts that are significantly characterized by anthropogenic topographic signatures: landscapes affected by mining activities, road networks and agricultural practices. We underline the main characteristics of those landscapes and the implications of human impacts on Earth surface processes. The final section considers future challenges wherein we explore recent novelties and trials in the concept of anthropogenic geomorphology. Herein, we focus on the role of high-resolution topographic and remote-sensing technologies. The reconstruction or identification of artificial or anthropogenic topographies provides a mechanism for quantifying anthropogenic changes to landscape systems. This study may allow an improved understanding and targeted mitigation of the processes driving geomorphic

  14. Influence of Fiber Orientation on Single-Point Cutting Fracture Behavior of Carbon-Fiber/Epoxy Prepreg Sheets

    Directory of Open Access Journals (Sweden)

    Yingying Wei

    2015-10-01

    Full Text Available 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.

  15. Application of laser spot cutting on spring contact probe for semiconductor package inspection

    Science.gov (United States)

    Lee, Dongkyoung; Cho, Jungdon; Kim, Chan Ho; Lee, Seung Hwan

    2017-12-01

    A packaged semiconductor has to be electrically tested to make sure they are free of any manufacturing defects. The test interface, typically employed between a Printed Circuit Board and the semiconductor devices, consists of densely populated Spring Contact Probe (SCP). A standard SCP typically consists of a plunger, a barrel, and an internal spring. Among these components, plungers are manufactured by a stamping process. After stamping, plunger connecting arms need to be cut into pieces. Currently, mechanical cutting has been used. However, it may damage to the body of plungers due to the mechanical force engaged at the cutting point. Therefore, laser spot cutting is considered to solve this problem. The plunger arm is in the shape of a rectangular beam, 50 μm (H) × 90 μm (W). The plunger material used for this research is gold coated beryllium copper. Laser parameters, such as power and elapsed time, have been selected to study laser spot cutting. Laser material interaction characteristics such as a crater size, material removal zone, ablation depth, ablation threshold, and full penetration are observed. Furthermore, a carefully chosen laser parameter (Etotal = 1000mJ) to test feasibility of laser spot cutting are applied. The result show that laser spot cutting can be applied to cut SCP.

  16. Influence of modern studded and bladed soccer boots and sidestep cutting on knee loading during match play conditions.

    Science.gov (United States)

    Kaila, Rajiv

    2007-09-01

    The influence of modern studded and bladed soccer boots and sidestep cutting on noncontact knee loading during match play conditions is not fully understood. Modern soccer boot type and sidestep cutting compared with straight-ahead running do not significantly influence knee internal tibia axial and valgus moments, anterior joint forces, and flexion angles. Controlled laboratory study. Fifteen professional male outfield soccer players undertook trials of straight-ahead running and sidestep cutting at 30 degrees and 60 degrees with a controlled approach velocity on a Fédération Internationale de Football Association (FIFA) approved soccer surface. Two bladed and 2 studded soccer boots from 2 manufacturers were investigated. Three-dimensional inverse dynamics analysis determined externally applied internal/external tibia axial and valgus/varus moments, anterior forces, and flexion angles throughout stance. The soccer boot type imparted no significant difference on knee loading for each maneuver. Internal tibia and valgus moments were significantly greater for sidestep cutting at 30 degrees and 60 degrees compared with straight-ahead running. Sidestep cutting at 60 degrees compared with straight-ahead running significantly increased anterior joint forces. Varying soccer boot type had no effect on knee loading for each maneuver, but sidestep cutting significantly increased internal tibia and valgus moments and anterior joint forces. Sidestep cutting, irrespective of the modern soccer boot type worn, may be implicated in the high incidence of noncontact soccer anterior cruciate ligament injuries by significantly altering knee loading.

  17. Effects of heat on cut mark characteristics.

    Science.gov (United States)

    Waltenberger, Lukas; Schutkowski, Holger

    2017-02-01

    Cut marks on bones provide crucial information about tools used and their mode of application, both in archaeological and forensic contexts. Despite a substantial amount of research on cut mark analysis and the influence of fire on bones (shrinkage, fracture pattern, recrystallisation), there is still a lack of knowledge in cut mark analysis on burnt remains. This study provides information about heat alteration of cut marks and whether consistent features can be observed that allow direct interpretation of the implemented tools used. In a controlled experiment, cut marks (n=25) were inflicted on pig ribs (n=7) with a kitchen knife and examined using micro-CT and digital microscopy. The methods were compared in terms of their efficacy in recording cut marks on native and heat-treated bones. Statistical analysis demonstrates that floor angles and the maximum slope height of cuts undergo significant alteration, whereas width, depth, floor radius, slope, and opening angle remain stable. Micro-CT and digital microscopy are both suitable methods for cut mark analysis. However, significant differences in measurements were detected between both methods, as micro-CT is less accurate due to the lower resolution. Moreover, stabbing led to micro-fissures surrounding the cuts, which might also influence the alteration of cut marks. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Maximizing biomarker discovery by minimizing gene signatures

    Directory of Open Access Journals (Sweden)

    Chang Chang

    2011-12-01

    Full Text Available Abstract Background The use of gene signatures can potentially be of considerable value in the field of clinical diagnosis. However, gene signatures defined with different methods can be quite various even when applied the same disease and the same endpoint. Previous studies have shown that the correct selection of subsets of genes from microarray data is key for the accurate classification of disease phenotypes, and a number of methods have been proposed for the purpose. However, these methods refine the subsets by only considering each single feature, and they do not confirm the association between the genes identified in each gene signature and the phenotype of the disease. We proposed an innovative new method termed Minimize Feature's Size (MFS based on multiple level similarity analyses and association between the genes and disease for breast cancer endpoints by comparing classifier models generated from the second phase of MicroArray Quality Control (MAQC-II, trying to develop effective meta-analysis strategies to transform the MAQC-II signatures into a robust and reliable set of biomarker for clinical applications. Results We analyzed the similarity of the multiple gene signatures in an endpoint and between the two endpoints of breast cancer at probe and gene levels, the results indicate that disease-related genes can be preferably selected as the components of gene signature, and that the gene signatures for the two endpoints could be interchangeable. The minimized signatures were built at probe level by using MFS for each endpoint. By applying the approach, we generated a much smaller set of gene signature with the similar predictive power compared with those gene signatures from MAQC-II. Conclusions Our results indicate that gene signatures of both large and small sizes could perform equally well in clinical applications. Besides, consistency and biological significances can be detected among different gene signatures, reflecting the

  19. Numerical Simulation of Fragment Separation during Rock Cutting Using a 3D Dynamic Finite Element Analysis Code

    Directory of Open Access Journals (Sweden)

    Zhenguo Lu

    2017-01-01

    Full Text Available To predict fragment separation during rock cutting, previous studies on rock cutting interactions using simulation approaches, experimental tests, and theoretical methods were considered in detail. This study used the numerical code LS-DYNA (3D to numerically simulate fragment separation. In the simulations, a damage material model and erosion criteria were used for the base rock, and the conical pick was designated a rigid material. The conical pick moved at varying linear speeds to cut the fixed base rock. For a given linear speed of the conical pick, numerical studies were performed for various cutting depths and mechanical properties of rock. The numerical simulation results demonstrated that the cutting forces and sizes of the separated fragments increased significantly with increasing cutting depth, compressive strength, and elastic modulus of the base rock. A strong linear relationship was observed between the mean peak cutting forces obtained from the numerical, theoretical, and experimental studies with correlation coefficients of 0.698, 0.8111, 0.868, and 0.768. The simulation results also showed an exponential relationship between the specific energy and cutting depth and a linear relationship between the specific energy and compressive strength. Overall, LS-DYNA (3D is effective and reliable for predicting the cutting performance of a conical pick.

  20. Effect of Rake Angle on Stress, Strain and Temperature on the Edge of Carbide Cutting Tool in Orthogonal Cutting Using FEM Simulation

    Directory of Open Access Journals (Sweden)

    Hendri Yanda

    2010-11-01

    Full Text Available Demand for higher productivity and good quality for machining parts has encourage many researchers to study the effects of machining parameters using FEM simulation using either two or three dimensions version. These are due to advantages such as software package and computational times are required. Experimental work is very costly, time consuming and labor intensive. The present work aims to simulate a three-dimensional orthogonal cutting operations using FEM software (Deform-3D to study the effects of rake angle on the cutting force, effective stress, strain and temperature on the edge of carbide cutting tool. There were seven runs of simulations. All simulations were performed for various rake angles of -15 deg, -10 deg, -5 deg, 0 deg, +5 deg, +10 deg, and +15 deg. The cutting speed, feed rate and depth of cut (DOC were kept constant at 100 m/min, 0.35 mm/rev and 0.3 mm respectively. The work piece used was ductile cast iron FCD500 grade and the cutting tool was DNMA432 series (tungsten, uncoated carbide tool, SCEA = 0; and radius angle 55 deg. The analysis of results show that, the increase in the rake angle from negative to positive angle, causing the decrease in cutting force, effective stress and total Von Misses strain. The minimum of the cutting force, effective stress and total Von Misses strain were obtained at rake angle of +15 deg. Increasing the rake caused higher temperature generated on the edge of carbide cutting tool and resulted in bigger contact area between the clearance face and the workpiece, consequently caused more friction and wear. The biggest deformation was occurred in the primary deformation zone, followed by the secondary deformation zone. The highest stress was also occurred in the primary deformation zone. But the highest temperature on the chip usually occurs in secondary deformation zone, especially in the sliding region, because the heat that was generated in the sticking region increased as the workpiece was

  1. Genomic Signatures of Sexual Conflict.

    Science.gov (United States)

    Kasimatis, Katja R; Nelson, Thomas C; Phillips, Patrick C

    2017-10-30

    Sexual conflict is a specific class of intergenomic conflict that describes the reciprocal sex-specific fitness costs generated by antagonistic reproductive interactions. The potential for sexual conflict is an inherent property of having a shared genome between the sexes and, therefore, is an extreme form of an environment-dependent fitness effect. In this way, many of the predictions from environment-dependent selection can be used to formulate expected patterns of genome evolution under sexual conflict. However, the pleiotropic and transmission constraints inherent to having alleles move across sex-specific backgrounds from generation to generation further modulate the anticipated signatures of selection. We outline methods for detecting candidate sexual conflict loci both across and within populations. Additionally, we consider the ability of genome scans to identify sexually antagonistic loci by modeling allele frequency changes within males and females due to a single generation of selection. In particular, we highlight the need to integrate genotype, phenotype, and functional information to truly distinguish sexual conflict from other forms of sexual differentiation. © The American Genetic Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Signature geometry and quantum engineering

    Science.gov (United States)

    Samociuk, Stefan

    2013-09-01

    As the operating frequency of electromagnetic based devices increase, physical design geometry is playing an ever more important role. Evidence is considered in support of a relationship between the dimensionality of primitive geometric forms, such as transistors, and corresponding electromagnetic coupling efficiency. The industry of electronics is defined as the construction of devices by the patterning of primitive forms to physical materials. Examples are given to show the evolution of these primitives, down to nano scales, are requiring exacting geometry and three dimensional content. Consideration of microwave monolithic integrated circuits,(MMIC), photonics and metamaterials,(MM), support this trend and also add new requirements of strict geometric periodicity and multiplicity. Signature geometries,(SG), are characterized by distinctive attributes and examples are given. The transcendent form transcode algorithm, (TTA) is introduced as a multi dimensional SG and its use in designing photonic integrated circuits and metamaterials is discussed . A creative commons licensed research database, TRANSFORM, containing TTA geometries in OASIS file formats is described. An experimental methodology for using the database is given. Multidimensional SG and extraction of three dimensional cross sections as primitive forms is discussed as a foundation for quantum engineering and the exploitation of phenomena other than the electromagnetic.

  3. Ceramic cutting tools materials, development and performance

    CERN Document Server

    Whitney, E Dow

    1994-01-01

    Interest in ceramics as a high speed cutting tool material is based primarily on favorable material properties. As a class of materials, ceramics possess high melting points, excellent hardness and good wear resistance. Unlike most metals, hardness levels in ceramics generally remain high at elevated temperatures which means that cutting tip integrity is relatively unaffected at high cutting speeds. Ceramics are also chemically inert against most workmetals.

  4. DIGITAL SIGNATURE IN THE WAY OF LAW

    OpenAIRE

    Ruya Samlı

    2013-01-01

    Signature can be defined as a person’s name or special signs that he/she writes when he/she wants to indicate he/she wrote or confirm that writing. A person signs many times in his/her life. A person’s signature that is used for thousands of times for many things from formal documents to exams has importance for that person. Especially, signing in legal operations is an operation that can build important results. If a person’s signature is imitated by another person, he/she can be...

  5. Arbitrated quantum signature scheme using Bell states

    International Nuclear Information System (INIS)

    Li Qin; Chan, W. H.; Long Dongyang

    2009-01-01

    In an arbitrated quantum signature scheme, the signatory signs the message and the receiver verifies the signature's validity with the assistance of the arbitrator. We present an arbitrated quantum signature scheme using two-particle entangled Bell states similar to the previous scheme using three-particle entangled Greenberger-Horne-Zeilinger states [G. H. Zeng and C. H. Keitel, Phys. Rev. A 65, 042312 (2002)]. The proposed scheme can preserve the merits in the original scheme while providing a higher efficiency in transmission and reducing the complexity of implementation.

  6. Reduction of a Ship's Magnetic Field Signatures

    CERN Document Server

    Holmes, John

    2008-01-01

    Decreasing the magnetic field signature of a naval vessel will reduce its susceptibility to detonating naval influence mines and the probability of a submarine being detected by underwater barriers and maritime patrol aircraft. Both passive and active techniques for reducing the magnetic signatures produced by a vessel's ferromagnetism, roll-induced eddy currents, corrosion-related sources, and stray fields are presented. Mathematical models of simple hull shapes are used to predict the levels of signature reduction that might be achieved through the use of alternate construction materials. Al

  7. Signature verification with writing posture analysis

    Science.gov (United States)

    Cheng, Hsu-Yung; Yu, Chih-Chang

    2013-07-01

    A video-based handwritten signature verification framework is proposed in this paper. Using a camera as the sensor has the advantage that the entire writing processes can be captured along with the signatures. The main contribution of this work is that writing postures are analyzed to achieve the verification purpose because the writing postures cannot be easily imitated or forged. The proposed system is able to achieve low false rejection rates while maintaining low false acceptance rates for database containing both unskilled and skilled imitation signatures.

  8. Molecular signatures of thyroid follicular neoplasia

    DEFF Research Database (Denmark)

    Borup, R.; Rossing, M.; Henao, Ricardo

    2010-01-01

    The molecular pathways leading to thyroid follicular neoplasia are incompletely understood, and the diagnosis of follicular tumors is a clinical challenge. To provide leads to the pathogenesis and diagnosis of the tumors, we examined the global transcriptome signatures of follicular thyroid...... a mechanism for cancer progression, which is why we exploited the results in order to generate a molecular classifier that could identify 95% of all carcinomas. Validation employing public domain and cross-platform data demonstrated that the signature was robust and could diagnose follicular nodules...... and robust genetic signature for the diagnosis of FA and FC. Endocrine-Related Cancer (2010) 17 691-708...

  9. Underwater laser cutting of metallic structures

    International Nuclear Information System (INIS)

    Alfille, J.P.; Schildknecht, J.; Ramaswami, V.S.

    1993-01-01

    In the frame of an european contract, the feasibility of the underwater cutting with a CO 2 laser power is studied. The aim of this work is the dismantling metallic structures of reactors pools. The paper analyzes the general concept of the experimental device, the underwater cutting head, the experimenting vessel, examples of cuttings in dismantling situation with a 500 W CO 2 laser, and examples of cuttings with a 5 kW CO 2 laser. (author). 2 refs., 9 figs., 2 tabs

  10. Machining Challenges: Macro to Micro Cutting

    Science.gov (United States)

    Shunmugam, M. S.

    2016-04-01

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

  11. Machinability baja AISI 1040 pada proses bubut dengan variasi cutting speed dan feed rate

    Directory of Open Access Journals (Sweden)

    AAIA Sri Komaladewi

    2012-11-01

    Full Text Available In order to obtain desired results of machining process (turning, parameter of process and material characteristic to be machined should be well known. This is due to different machining conditions and material yield different material machinability as well. It is needed to investigate of material machinability (AISI 1040 such as force, power and shear angle under different cutting speed (80, 160 and 240 m/min and feed rate (0.1, 0.2, and 0.3 mm/rev. The results of investigation show that; at the same cutting speed the higher feed rate the higher cutting force needed; the higher cutting speed and feed rate, the higher power needed; at feed rate 0.1 mm./rev and 0.3 mm/rev, the higher cutting speed the shear angles has a trend to incline; at feed rate 0.2 mm/rev, cutting speed from 80 to 160 m/min yield increasing of shear angle, however, from 160 to 240 m/min shear angle declines.

  12. Effect of nose radius on forces, and process parameters in hot machining of Inconel 718 using finite element analysis

    Directory of Open Access Journals (Sweden)

    Asit Kumar Parida

    2017-04-01

    Full Text Available In the present work, the variation of nose radius on forces, cutting temperature, stress, has been studied using finite element modeling in hot turning operation of Inconel 718. Three values of nose radius were taken (0.4, 0.8 and 1.2 mm. Cutting force, thrust force, stress, and cutting temperature have been predicted using commercial DEFORM™ software at different cutting tool nose radius in both room and heated conditions. With the increase of tool nose radius in both room and elevated machining conditions the cutting force and thrust force increased. The cutting temperature, chip thickness and chip tool contact length also have been studied. In order to validate the numerical results an experimental analysis has been performed and good agreement between them has been observed

  13. Statistical analysis of surface roughness in turning based on cutting parameters and tool vibrations with response surface methodology (RSM)

    Science.gov (United States)

    Touati, Soufiane; Mekhilef, Slimane

    2018-03-01

    In this paper, we present an experimental study to determine the effect of the cutting conditions and tool vibration on the surface roughness in finish turning of 32CrMoV12-28 steel, using carbide cutting tool YT15. For these purposes, a linear quadratic model in interaction of connecting surface roughness (Ra, Rz) with different combinations of cutting parameters such as cutting speed, feed rate, depth of cut and tool vibration, in radial and in tangential cutting force directions (Vy) and (Vz) is elaborated. In order to express the degree of interaction of cutting parameters and tool vibration, a multiple linear regression and response surface methodology are adopted. The application of this statistical technique for predicting the surface roughness shows that the feed rate is the most dominant factor followed by the cutting speed. However, the depth of the cut and tool vibrations have secondary effect. The presented models have some interest since they are used in the cutting process optimization.

  14. In vitro assessment of cutting efficiency and durability of zirconia removal diamond rotary instruments.

    Science.gov (United States)

    Kim, Joon-Soo; Bae, Ji-Hyeon; Yun, Mi-Jung; Huh, Jung-Bo

    2017-06-01

    Recently, zirconia removal diamond rotary instruments have become commercially available for efficient cutting of zirconia. However, research of cutting efficiency and the cutting characteristics of zirconia removal diamond rotary instruments is limited. The purpose of this in vitro study was to assess and compare the cutting efficiency, durability, and diamond rotary instrument wear pattern of zirconia diamond removal rotary instruments with those of conventional diamond rotary instruments. In addition, the surface characteristics of the cut zirconia were assessed. Block specimens of 3 mol% yttrium cation-doped tetragonal zirconia polycrystal were machined 10 times for 1 minute each using a high-speed handpiece with 6 types of diamond rotary instrument from 2 manufacturers at a constant force of 2 N (n=5). An electronic scale was used to measure the lost weight after each cut in order to evaluate the cutting efficiency. Field emission scanning electron microscopy was used to evaluate diamond rotary instrument wear patterns and machined zirconia block surface characteristics. Data were statistically analyzed using the Kruskal-Wallis test, followed by the Mann-Whitney U test (α=.05). Zirconia removal fine grit diamond rotary instruments showed cutting efficiency that was reduced compared with conventional fine grit diamond rotary instruments. Diamond grit fracture was the most dominant diamond rotary instrument wear pattern in all groups. All machined zirconia surfaces were primarily subjected to plastic deformation, which is evidence of ductile cutting. Zirconia blocks machined with zirconia removal fine grit diamond rotary instruments showed the least incidence of surface flaws. Although zirconia removal diamond rotary instruments did not show improved cutting efficiency compared with conventional diamond rotary instruments, the machined zirconia surface showed smoother furrows of plastic deformation and fewer surface flaws. Copyright © 2016 Editorial Council

  15. ΔI = 1 Signature Splitting in Signature Partners of Odd Mass Superdeformed Nuclei

    Directory of Open Access Journals (Sweden)

    Khalaf A. M.,

    2013-07-01

    Full Text Available The spins, transition energies, rotational frequencies, kinematic and dynamic moment of inertia of rotational bands of signature partners pairs of odd–A superdeformed bands in A190 region were calculated by proposing a simple model based on collective rotational model. Simulated search program was written to determine the model parameters. The calculated results agree with experimental data for fourteen signature partner pairs in Hg/Tl/Pb/Bi/nuclei. We investigated the ∆I=1 signature splitting by extracted the difference between the average transitions I+2 ! I and I ! I-2 energies in one band and the transition I+1 ! I-1 energies in its signature partner. Most of the signature partners in this region show large amplitude staggering. The signature splitting has the effect of increasing dynamical moment of inertia J 2 for favored band and decreasing J 2 for the unfavored band.

  16. Blind Quantum Signature with Blind Quantum Computation

    Science.gov (United States)

    Li, Wei; Shi, Ronghua; Guo, Ying

    2017-04-01

    Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

  17. Breakthrough Listen: Searching for Signatures of Technology

    Science.gov (United States)

    Isaacson, H. T.; Siemion, A. P. V.

    2017-11-01

    Breakthrough Listen is searching for signals of extra-terrestrial technologies using radio and optical telescopes. Very nearby stars of all types. Stars across the HR diagram and galaxies are all of interest in the search for techno-signatures.

  18. Magnetic signature surveillance of nuclear fuel

    International Nuclear Information System (INIS)

    Bernatowicz, H.; Schoenig, F.C.

    1981-01-01

    Typical nuclear fuel material contains tramp ferromagnetic particles of random size and distribution. Also, selected amounts of paramagnetic or ferromagnetic material can be added at random or at known positions in the fuel material. The fuel material in its non-magnetic container is scanned along its length by magnetic susceptibility detecting apparatus whereby susceptibility changes along its length are obtained and provide a unique signal waveform of the container of fuel material as a signature thereof. The output signature is stored. At subsequent times in its life the container is again scanned and respective signatures obtained which are compared with the initially obtained signature, any differences indicating alteration or tampering with the fuel material. If the fuel material includes a paramagnetic additive by taking two measurements along the container the effects thereof can be cancelled out. (author)

  19. Magnetic Signature of Brushless Electric Motors

    National Research Council Canada - National Science Library

    Clarke, David

    2006-01-01

    Brushless electric motors are used in a number of underwater vehicles. When these underwater vehicles are used for mine clearance operations the magnetic signature of the brushless motors is important...

  20. Isotopic signatures by bulk analyses

    International Nuclear Information System (INIS)

    Efurd, D.W.; Rokop, D.J.

    1997-01-01

    Los Alamos National Laboratory has developed a series of measurement techniques for identification of nuclear signatures by analyzing bulk samples. Two specific applications for isotopic fingerprinting to identify the origin of anthropogenic radioactivity in bulk samples are presented. The first example is the analyses of environmental samples collected in the US Arctic to determine the impact of dumping of radionuclides in this polar region. Analyses of sediment and biota samples indicate that for the areas sampled the anthropogenic radionuclide content of sediments was predominantly the result of the deposition of global fallout. The anthropogenic radionuclide concentrations in fish, birds and mammals were very low. It can be surmised that marine food chains are presently not significantly affected. The second example is isotopic fingerprinting of water and sediment samples from the Rocky Flats Facility (RFP). The largest source of anthropogenic radioactivity presently affecting surface-waters at RFP is the sediments that are currently residing in the holding ponds. One gram of sediment from a holding pond contains approximately 50 times more plutonium than 1 liter of water from the pond. Essentially 100% of the uranium in Ponds A-1 and A-2 originated as depleted uranium. The largest source of radioactivity in the terminal Ponds A-4, B-5 and C-2 was naturally occurring uranium and its decay product radium. The uranium concentrations in the waters collected from the terminal ponds contained 0.05% or less of the interim standard calculated derived concentration guide for uranium in waters available to the public. All of the radioactivity observed in soil, sediment and water samples collected at RFP was naturally occurring, the result of processes at RFP or the result of global fallout. No extraneous anthropogenic alpha, beta or gamma activities were detected. The plutonium concentrations in Pond C-2 appear to vary seasonally

  1. Technology development for cutting a reactor pressure vessel using a mechanical cutting technique

    International Nuclear Information System (INIS)

    Watanabe, Masaaki; Miyasaka, Yasuhiko; Miyao, Hidehiko; Ooki, Arahiko; Ninomiya, Toshiaki; Koiwai, Masami

    2001-01-01

    On decommissioning of nuclear facilities, the thermal cutting technique such as an oxygen-acetylene gas cutting and a plasma arc cutting are generally used for cutting massive and thick steel structures in consideration with cutting speed and control performance. These techniques generate dust, smoke, aerosol and a large quantity of secondary waste. Mechanical cutting technique has an advantage of small amount of secondary waste, and the metal chips from the kerf recovered easily compared with these thermal cutting technique. The remote mechanical cutting system for highly activated RPV has been developed with the manner which achieves the safety and cost effectiveness. The development has been performed on consignment to RANDEC from the Science and Technology Agency of Japan. (author)

  2. Signature for the shape of the universe

    International Nuclear Information System (INIS)

    Gomero, G.I.; Reboucas, M.J.; Teixeira, A.F.F.

    2001-03-01

    If the universe has a nontrival shape (topology) the sky may show multiple correlated images of cosmic objects. These correlations can be counched in terms of distance correlations. We propose a statistical quantity which can be used to reveal the topological signature of any Roberston-Walker (RW) spacetime with nontrivial topology. We also show through computer-aided simulations how one can extract the topological signatures of flat elliptic and hyperbolic RW universes with nontrivial topology. (author)

  3. Signature-based store checking buffer

    Science.gov (United States)

    Sridharan, Vilas; Gurumurthi, Sudhanva

    2015-06-02

    A system and method for optimizing redundant output verification, are provided. A hardware-based store fingerprint buffer receives multiple instances of output from multiple instances of computation. The store fingerprint buffer generates a signature from the content included in the multiple instances of output. When a barrier is reached, the store fingerprint buffer uses the signature to verify the content is error-free.

  4. Tightly Secure Signatures From Lossy Identification Schemes

    OpenAIRE

    Abdalla , Michel; Fouque , Pierre-Alain; Lyubashevsky , Vadim; Tibouchi , Mehdi

    2015-01-01

    International audience; In this paper, we present three digital signature schemes with tight security reductions in the random oracle model. Our first signature scheme is a particularly efficient version of the short exponent discrete log-based scheme of Girault et al. (J Cryptol 19(4):463–487, 2006). Our scheme has a tight reduction to the decisional short discrete logarithm problem, while still maintaining the non-tight reduction to the computational version of the problem upon which the or...

  5. Monitoring system for automation of experimental researches in cutting

    International Nuclear Information System (INIS)

    Kuzinovski, Mikolaj; Trajchevski, Neven; Filipovski, Velimir; Tomov, Mite; Cichosz, Piotr

    2009-01-01

    This study presents procedures being performed when projecting and realizing experimental scientific researches by application of the automated measurement system with a computer support in all experiment stages. A special accent is placed on the measurement system integration and mathematical processing of data from experiments. Automation processes are described through the realized own automated monitoring system for research of physical phenomena in the cutting process with computer-aided data acquisition. The monitoring system is intended for determining the tangential, axial and radial component of the cutting force, as well as average temperature in the cutting process. The hardware acquisition art consists of amplifiers and A/D converters, while as for analysis and visualization software for P C is developed by using M S Visual C++. For mathematical description researched physical phenomena CADEX software is made, which in connection with MATLAB is intended for projecting processing and analysis of experimental scientific researches against the theory for planning multi-factorial experiments. The design and construction of the interface and the computerized measurement system were done by the Faculty of Mechanical Engineering in Skopje in collaboration with the Faculty of Electrical Engineering and Information Technologies in Skopje and the Institute of Production Engineering and Automation, Wroclaw University of Technology, Poland. Gaining own scientific research measurement system with free access to hardware and software parts provides conditions for a complete control of the research process and reduction of interval of the measuring uncertainty of gained results from performed researches.

  6. A Range-Balanced Force: An Alternate Force Structure Adapted to New Defense Priorities

    Science.gov (United States)

    2013-06-01

    forces will likely feature two aircraft types not currently contemplated in Air Force budgets—a medium-range unmanned combat aerial vehi- cle ( UCAV ...Dassault nEURon UCAV , scheduled to fly in 2012, doing what they think America’s cutting-edge Air Force is “supposed to do.” That pres- sure includes the OSD...long-legged, stealthy UCAV will cer- tainly cause policy analysts, budget-waste cutters, and Congress to ask why the Air Force isn’t buying the same

  7. Experimental research on the durability cutting tools for cutting-off steel profiles

    Directory of Open Access Journals (Sweden)

    Cristea Alexandru

    2017-01-01

    Full Text Available The production lines used for manufacturing U-shaped profiles are very complex and they must have high productivity. One of the most important stages of the fabrication process is the cutting-off. This paper presents the experimental research and analysis of the durability of the cutting tools used for cutting-off U-shaped metal steel profiles. The results of this work can be used to predict the durability of the cutting tools.

  8. Cutting a drop of water pinned by wire loops using a superhydrophobic surface and knife.

    Directory of Open Access Journals (Sweden)

    Ryan Yanashima

    Full Text Available A water drop on a superhydrophobic surface that is pinned by wire loops can be reproducibly cut without formation of satellite droplets. Drops placed on low-density polyethylene surfaces and Teflon-coated glass slides were cut with superhydrophobic knives of low-density polyethylene and treated copper or zinc sheets, respectively. Distortion of drop shape by the superhydrophobic knife enables a clean break. The driving force for droplet formation arises from the lower surface free energy for two separate drops, and it is modeled as a 2-D system. An estimate of the free energy change serves to guide when droplets will form based on the variation of drop volume, loop spacing and knife depth. Combining the cutting process with an electrofocusing driving force could enable a reproducible biomolecular separation without troubling satellite drop formation.

  9. Leptonic signatures of doubly charged Higgs boson production at the LHC

    Science.gov (United States)

    Akeroyd, A. G.; Chiang, Cheng-Wei; Gaur, Naveen

    2010-11-01

    The production of doubly charged Higgs bosons ( H ±±) at the CERN LHC can give rise to distinctive multi-lepton signatures. The discovery potential of H ±± can be optimized by considering a search strategy which is sensitive to both of the dominant production mechanisms, qbar{q} to {H^{ + + }}{H^{ - - }} and qoverline {q'} to {H^{± ± }}{H^mp } . We compare the discovery potential for the signatures of exactly four leptons and at least three leptons in the final state, using the same set of cuts. We have carried out fast detector simulations at the LHC for both signal and backgrounds for a wide range of values of the charged Higgs mass. We find that the use of the latter channel can substantially improve the detection prospects of the doubly charged Higgs boson at the LHC.

  10. Impalement oral injury: Ultrasonic scalpel is the best tool to cut off a toothbrush.

    Science.gov (United States)

    Yamaguchi, Yoshikazu; Miyashita, Tetsuya; Toki, Keiko; Takaki, Shunsuke; Goto, Takahisa

    2015-01-01

    Penetrating injuries to the oral cavity involving a toothbrush are relatively common among children. Sometimes general anesthesia is recommended. Although the handle prevents adequate mask ventilation in the induction of anesthesia, it is unknown what is the best tool to cut it preventing complications. The aim of this study was to evaluate the optimal tool to cut off the toothbrush handle. Six anesthesiologists participated in this study. We attached a triaxial acceleration sensor to the tip of the toothbrush to virtually measure force toward the wound. Each participant cut off the handle of the toothbrush using 3 tools: Gluck rib shears (GRS: cutting horizonal); Sklar Coryllos rib shears (SCRS: cutting vertical); and an ultrasonic scalpel (USS). Acceleration and time required to cut the toothbrush were measured. Each anesthesiologist evaluated the usability of each tool on a 5-point scale. The USS showed the longest mean time (GRS, 1.78 ± 1.01 s; SCRS, 7.30 ± 4.58 s; USS, 28.13 ± 13.41 s), lowest 3-dimensional acceleration (GRS, 2.15 ± 0.69 G; SCRS, 2.13 ± 0.57 G; USS, 1.01 ± 1.07 G), and highest mean score for usability. The USS appeared preferable to rib shears for cutting off toothbrush handles, even though it takes longer.

  11. Actuator design for vibration assisted machining of high performance materials with ultrasonically modulated cutting speed

    Science.gov (United States)

    Rinck, Philipp M.; Sitzberger, Sebastian; Zaeh, Michael F.

    2017-06-01

    In vibration assisted machining, an additional high-frequency oscillation is superimposed on the kinematics of the conventional machining process. This generates oscillations on the cutting edge in the range of a few micrometers, thereby causing a high-frequency change in the cutting speed or the feed. Consequently, a reduction of cutting forces, an increase of the tool life as well as an improvement of the workpiece quality can be achieved. In milling and grinding it has been shown that these effects are already partially present in the case of a vibration excitation in axial direction relative to the workpiece, which is perpendicular to the cutting direction. Further improvements of the process results can be achieved by superimposing a vibration in cutting direction and thus modifying the cutting speed at high frequency. The presented work shows the design of an ultrasonic actuator that enables vibration-assisted milling and grinding with ultrasonically modulated cutting speed. The actuator system superimposes a longitudinal torsional ultrasonic oscillation to the milling or grinding tool. It uses a bolt clamped Langevin transducer and a helically slotted horn, which degenerates the longitudinal vibration into a combined longitudinal torsional (L-T) vibration at the output surface. A finite element analysis is used to determine the vibration resonance frequency and mode shapes to maximize the torsional output. Afterwards, the simulation has been experimentally validated.

  12. 27 CFR 6.92 - Newspaper cuts.

    Science.gov (United States)

    2010-04-01

    ... OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers' advertisements may be given or sold by an industry member to a retailer selling the industry member's products. [T.D. ATF-364, 60 FR 20423, Apr. 26, 1995] ...

  13. Automated harvesting of flowers and cuttings

    NARCIS (Netherlands)

    Rosier, J.C.; Snel, R.; Goedvolk, E.J.

    1996-01-01

    The harvesting of flowers and cuttings can be considered as a skilled task. It takes weeks of training for the pickers to harvest quality cutting at the required production rate of one per second. The skill of the pickers is the ability to execute a number of functions within a short time. The

  14. Electroencephalographic responses to neck cut and exsanguination ...

    African Journals Online (AJOL)

    user

    2016-12-09

    Dec 9, 2016 ... The data of EEG from 60-second blocks prior to neck cut to 90-second blocks post neck cut were taken for statistical analysis based on the time to .... reported an initial increase in total EEG power in lambs of different ages undergoing rubber-ring castration. In these cases, the increase in total EEG power ...

  15. Postharvest: Cut flowers and potted plants

    Science.gov (United States)

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

  16. Cost of cutting grapevines before logging

    Science.gov (United States)

    H. Clay Smith; Paul M. Smithson

    1975-01-01

    To reduce damage to hardwood stems by grapevines, it is recommended that grapevines be cut near ground level several years before the harvest cutting. Cost of completing this practice on 117 acres supporting 22 vines per acre was found to be about $3.50 per acre.

  17. Cutting Watermelon: Lessons in Instructional Coaching

    Science.gov (United States)

    Sandstead, Martha

    2016-01-01

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

  18. Laser cutting - trends in the development,

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2002-01-01

    Since the laser was invented in 1960, the industrial applications of this tool has grown and grown. And - since the beginning of the 1980'ies, the major industrial application of lasers in production has been laser cutting. In this paper a short review of the development of the laser cutting...

  19. Drilling subsurface wellbores with cutting structures

    Science.gov (United States)

    Mansure, Arthur James; Guimerans, Rosalvina Ramona

    2010-11-30

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

  20. In the suppression of regge cut contributions

    International Nuclear Information System (INIS)

    Chia, S.P.

    1975-07-01

    It is shown that contributions of reggeon-pomeron cuts are suppressed in amplitudes with opposite natural to the reggeon. This suppression grows logarithmically with energy. The suppression in the πP cut is, however, found to be weak. Consequence on conspiracy is discussed

  1. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is

  2. Effects of vegetable-based cutting fluids on the wear in drilling

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... In this study, performances of three VBCFs developed from crude sunflower oil, refined sunflower oil, refined canola oil and commercial semi-synthetic cutting fluid are compared in terms of tool wear, thrust force and surface roughness during drilling of AISI 304 austenitic stainless steel with HSSE tool.

  3. Influence of edging practices on cutting yields of Alaska birch lumber

    Science.gov (United States)

    David L. Nicholls; J.W. Funck; C.C. Brunner; J.E. Reeb

    2009-01-01

    Birch lumber is often characterized by a high degree of knots, bark pockets, heartwood, and other features which force sawmill owners to decide whether to edge and trim boards to produce standard grade lumber vs. proprietary grade character-marked lumber. In addition, the edging strategies used with irregularly shaped flitches can greatly influence cut-stock recovery....

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

    Science.gov (United States)

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

    2011-01-01

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

  5. High precision tungsten cutting for optics

    International Nuclear Information System (INIS)

    Reglero, V.; Velasco, T.; Rodrigo, J.; Gasent, L.J.; Alamo, J.; Chato, R.; Ruiz Urien, I.; Santos, I.; Zarauz, J.; Clemente, G.; Sanz-Tudanca, C.; Lopez, J.L.

    2001-01-01

    The results obtained during the INTEGRAL masks development program an implementing the HURA and MURA codes on tungsten plates of different thickness are presented. Hard scientific requirements on pixels size and location tolerances (tenths of microns over large areas -1 m 2 - and thickness from 0.5 mm to 60 mm) required the set up of a dedicated program for testing cutting technologies: laser, photochemical milling, spark machining and electro discharge wire cutting. After a very intensive test campaign the wire cutting process was selected as the optimum technology for code manufacturing . Accuracies achieved an the code cutting fulfill scientific requirements. In fact, they are 5 times better than required. Pixel size and centroids location accuracies of 0.01 mm over a 1 m 2 area have been obtained for the 10,000 pixels on IBIS, 100 pixels on SPI and 24000 pixels on JEM-X masks. Comparative results among different cutting technologies are also discussed. (author)

  6. Cutting as a continuous business process

    Directory of Open Access Journals (Sweden)

    Miro Gradišar

    2009-11-01

    Full Text Available A review of state-of-the-art methods for cutting stock problem optimisation shows that the current methods lead to near-optimum results for the instantaneous optimisation of trim loss. Further optimisation of this activity would not bring a considerable improvement. Therefore, the paper treats cutting stock as a continuous business process and not as an isolated activity. An exact method for a general one-dimensional cutting stock problem is presented and tested. The method is mainly suitable for smaller orders. It is then applied to continuous cutting and used to develop a method for assessing cutting costs in consecutive time periods. The modified method finds a good solution over the whole time-span, rather than just local optima.

  7. Electric arc, water jet cutting of metals

    International Nuclear Information System (INIS)

    Bruening, D.

    1991-01-01

    For thermal dismantling and cutting of metallic components, as electric arc, water jet cutting method was developed that can be used for underwater cutting work up to a depth of 20 m. Short-circuiting of a continuously fed electrode wire in contact with the metal generates an electric arc which induces partial melting of the metal, and the water jet surrounding the wire rinses away the molten material, thus making a continuous kerf in the material. The method was also tested and modified to allow larger area, surface cutting and removal of metallic surface coatings. This is achieved by melting parts of the surface with the electric arc and subsequent rinsing by the water jet. The cutting and melting depth for surface removal can be accurately controlled by the operating parameters chosen. (orig./DG) [de

  8. Effects of Cutting Tool Parameters on Vibration

    Directory of Open Access Journals (Sweden)

    Ince Mehmet Alper

    2016-01-01

    Full Text Available This paper presents of the influence on vibration of Co28Cr6Mo medical alloy machined on a CNC lathe based on cutting parameters (rotational speed, feed rate, depth of cut and tool tip radius. The influences of cutting parameters have been presented in graphical form for understanding. To achieve the minimum vibration, the optimum values obtained for rpm, feed rate, depth of cut and tool tip radius were respectively, 318 rpm, 0.25 mm/rev, 0.9 mm and 0.8 mm. Maximum vibration has been revealed the values obtained for rpm, feed rate, depth of cut and tool tip radius were respectively, 636 rpm, 0.1 mm/rev, 0,5 mm and 0.8 mm.

  9. Changing cultural attitudes towards female genital cutting.

    Science.gov (United States)

    Vogt, Sonja; Mohmmed Zaid, Nadia Ahmed; El Fadil Ahmed, Hilal; Fehr, Ernst; Efferson, Charles

    2016-10-27

    As globalization brings people with incompatible attitudes into contact, cultural conflicts inevitably arise. Little is known about how to mitigate conflict and about how the conflicts that occur can shape the cultural evolution of the groups involved. Female genital cutting is a prominent example. Governments and international agencies have promoted the abandonment of cutting for decades, but the practice remains widespread with associated health risks for millions of girls and women. In their efforts to end cutting, international agents have often adopted the view that cutting is locally pervasive and entrenched. This implies the need to introduce values and expectations from outside the local culture. Members of the target society may view such interventions as unwelcome intrusions, and campaigns promoting abandonment have sometimes led to backlash as they struggle to reconcile cultural tolerance with the conviction that cutting violates universal human rights. Cutting, however, is not necessarily locally pervasive and entrenched. We designed experiments on cultural change that exploited the existence of conflicting attitudes within cutting societies. We produced four entertaining movies that served as experimental treatments in two experiments in Sudan, and we developed an implicit association test to unobtrusively measure attitudes about cutting. The movies depart from the view that cutting is locally pervasive by dramatizing members of an extended family as they confront each other with divergent views about whether the family should continue cutting. The movies significantly improved attitudes towards girls who remain uncut, with one in particular having a relatively persistent effect. These results show that using entertainment to dramatize locally discordant views can provide a basis for applied cultural evolution without accentuating intercultural divisions.

  10. Electronic Signatures: They're Legal, Now What?

    Science.gov (United States)

    Broderick, Martha A.; Gibson, Virginia R.; Tarasewich, Peter

    2001-01-01

    In the United States, electronic signatures recently became as legally binding as printed signatures. Reviews the status of electronic signatures in the United States, and compares it to work done by the United Nations. Summarizes the technology that can be used to implement electronic signatures. Discusses problems and open issues surrounding the…

  11. An efficient modified Elliptic Curve Digital Signature Algorithm | Kiros ...

    African Journals Online (AJOL)

    Many digital signatures which are based on Elliptic Curves Cryptography (ECC) have been proposed. Among these digital signatures, the Elliptic Curve Digital Signature Algorithm (ECDSA) is the widely standardized one. However, the verification process of ECDSA is slower than the signature generation process. Hence ...

  12. Cluster forcing

    DEFF Research Database (Denmark)

    Christensen, Thomas Budde

    , Portugal and New Zealand have adopted the concept. Public sector interventions that aim to support cluster development in industries most often focus upon economic policy goals such as enhanced employment and improved productivity, but rarely emphasise broader societal policy goals relating to e.......g. sustainability or quality of life. The purpose of this paper is to explore how and to what extent public sector interventions that aim at forcing cluster development in industries can support sustainable development as defined in the Brundtland tradition and more recently elaborated in such concepts as eco...... in 2000 by the Welsh Automotive Task Force under the Welsh Assembly Government. The Accelerate programme takes basically different two directions: The first one, which was the first to be launched, is concerned with the upgrading of existing supply chains in the automotive industry in Wales. The programme...

  13. Calculation of mass transfer in the remote cutting of metals by radiation of a high-power repetitively pulsed CO2 laser

    International Nuclear Information System (INIS)

    Gladush, G G; Rodionov, N B

    2002-01-01

    The mechanism of remote cutting of steel plates by radiation of a high-power repetitively pulsed CO 2 laser is theoretically studied. The models of melt removal by the gravity force and the recoil pressure of material vapour are proposed and the sufficient conditions for the initiation of cutting are determined. A numerical model of a thermally thin plate was employed to describe the cutting for large focal spots. (interaction of laser radiation with matter. laser plasma)

  14. Does Twitter trigger bursts in signature collections?

    Science.gov (United States)

    Yamaguchi, Rui; Imoto, Seiya; Kami, Masahiro; Watanabe, Kenji; Miyano, Satoru; Yuji, Koichiro

    2013-01-01

    The quantification of social media impacts on societal and political events is a difficult undertaking. The Japanese Society of Oriental Medicine started a signature-collecting campaign to oppose a medical policy of the Government Revitalization Unit to exclude a traditional Japanese medicine, "Kampo," from the public insurance system. The signature count showed a series of aberrant bursts from November 26 to 29, 2009. In the same interval, the number of messages on Twitter including the keywords "Signature" and "Kampo," increased abruptly. Moreover, the number of messages on an Internet forum that discussed the policy and called for signatures showed a train of spikes. In order to estimate the contributions of social media, we developed a statistical model with state-space modeling framework that distinguishes the contributions of multiple social media in time-series of collected public opinions. We applied the model to the time-series of signature counts of the campaign and quantified contributions of two social media, i.e., Twitter and an Internet forum, by the estimation. We found that a considerable portion (78%) of the signatures was affected from either of the social media throughout the campaign and the Twitter effect (26%) was smaller than the Forum effect (52%) in total, although Twitter probably triggered the initial two bursts of signatures. Comparisons of the estimated profiles of the both effects suggested distinctions between the social media in terms of sustainable impact of messages or tweets. Twitter shows messages on various topics on a time-line; newer messages push out older ones. Twitter may diminish the impact of messages that are tweeted intermittently. The quantification of social media impacts is beneficial to better understand people's tendency and may promote developing strategies to engage public opinions effectively. Our proposed method is a promising tool to explore information hidden in social phenomena.

  15. Does Twitter trigger bursts in signature collections?

    Directory of Open Access Journals (Sweden)

    Rui Yamaguchi

    Full Text Available INTRODUCTION: The quantification of social media impacts on societal and political events is a difficult undertaking. The Japanese Society of Oriental Medicine started a signature-collecting campaign to oppose a medical policy of the Government Revitalization Unit to exclude a traditional Japanese medicine, "Kampo," from the public insurance system. The signature count showed a series of aberrant bursts from November 26 to 29, 2009. In the same interval, the number of messages on Twitter including the keywords "Signature" and "Kampo," increased abruptly. Moreover, the number of messages on an Internet forum that discussed the policy and called for signatures showed a train of spikes. METHODS AND FINDINGS: In order to estimate the contributions of social media, we developed a statistical model with state-space modeling framework that distinguishes the contributions of multiple social media in time-series of collected public opinions. We applied the model to the time-series of signature counts of the campaign and quantified contributions of two social media, i.e., Twitter and an Internet forum, by the estimation. We found that a considerable portion (78% of the signatures was affected from either of the social media throughout the campaign and the Twitter effect (26% was smaller than the Forum effect (52% in total, although Twitter probably triggered the initial two bursts of signatures. Comparisons of the estimated profiles of the both effects suggested distinctions between the social media in terms of sustainable impact of messages or tweets. Twitter shows messages on various topics on a time-line; newer messages push out older ones. Twitter may diminish the impact of messages that are tweeted intermittently. CONCLUSIONS: The quantification of social media impacts is beneficial to better understand people's tendency and may promote developing strategies to engage public opinions effectively. Our proposed method is a promising tool to explore

  16. Laser circular cutting of Kevlar sheets: Analysis of thermal stress filed and assessment of cutting geometry

    Science.gov (United States)

    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.

  17. Restraining and neck cutting or stunning and neck cutting of veal calves.

    Science.gov (United States)

    Lambooij, E; van der Werf, J T N; Reimert, H G M; Hindle, V A

    2012-05-01

    Brain and heart activities were measured in 31 veal calves during restraining and rotating followed by neck cutting with or without stunning to evaluate welfare. After neck cutting correlation dimension analyses and %power of EEG beta wave fraction decreased gradually to lower values resulting in an induction of unconsciousness lasting on average 80s. Corneal reflex response ceased 135±57s after neck cutting. The CD scores and the %power of beta waves fell immediately after post-cut captive bolt and pre-cut electrical stunning to levels indicating unconsciousness. Heart rate in lairage increased upon entrance to the restrainer and again after rotation, heart rate variability decreased. Rotating the restrainer 90°, 120° or 180° compromised veal calf welfare and should be avoided. It is recommended to use post-cut captive bolt stunning or pre-cut electrical stunning inducing immediate unconsciousness. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Mist, substrate water potential and cutting water potential influence rooting of stem cuttings of loblolly pine.

    Science.gov (United States)

    Lebude, Anthony V; Goldfarb, Barry; Blazich, Frank A; Wise, Farrell C; Frampton, John

    2004-07-01

    We investigated the influence of cutting water potential (Psicut) on rooting of juvenile hardwood (dormant) and softwood (succulent) stem cuttings of loblolly pine (Pinus taeda L.) propagated under varying substrate water potentials (Psisub) and volumes of mist application. Mist treatment and Psisub contributed to the Psicut of unrooted stem cuttings. When Psisub was held constant across mist treatments, mist treatment contributed strongly to Psicut. Substrate water potential affected rooting percentage when mist treatment was sub-optimal or excessive, otherwise mist treatment had a stronger effect than Psisub on rooting percentage. Cuttings rooted best when subjected to moderate cutting water potentials (-0.5 to -1.2 MPa) during the initial 4 or 5 weeks of the rooting period. Cuttings experiencing either severe water deficit or no water deficit rooted poorly. We conclude that the rooting environment should impose a moderate water stress on loblolly pine stem cuttings to achieve optimum rooting. Copyright 2004 Heron Publishing

  19. Laser cutting of sheets for Tailored Blanks

    DEFF Research Database (Denmark)

    Bagger, Claus; Olsen, Flemming Ove

    1999-01-01

    Over the past few years there has been an enormous increase in the use of tailored blanks, especially in the automotive industry. Often the sheets for tailored blanks are shear cut, but results have been reported that the allowable sheet gap distance should not exceed 0.1 mm in order to obtain...... sound welds. Laser cutting the sheets may therefore be an alternative to shear cutting, if the cut kerf squareness can be kept below 0.05 mm.In a number of systematic laboratory experiments the effects of the major process parameters in laser cutting have been investigated. Each cut was quantified...... by the squareness, the surface roughness and the burr height. Mild steel as well as high strength steel with and with out galvanisation with thickness' of 0.7(5) and 1.25 were used.In the tests the difference in cut quality between a 5" and a 7.5" focusing lens were tested and the effect of using pulsed mode laser...

  20. The signature of the city: abandonment and dreaming in colonial Williamsburg and Ottawa

    Directory of Open Access Journals (Sweden)

    Mark Kristmanson

    2011-06-01

    Full Text Available Exploring the themes of abandonment and dreaming in relation to two North American capital cities, this interdisciplinary narrative essay examines the Canadian Prime Minister William Lyon Mackenzie King's influence on the planning and architecture of Ottawa in relation to his frequent visits to Colonial Williamsburg, the restored former capital of Virginia. At the invitation of John D. Rockefeller Jr., King became a regular guest in Williamsburg during the 1930s and 1940s culminating in the conferral of an honorary degree by the College of William and Mary in 1948. The records of these visits provide a diagnostic used to conceptualize the 'signature' of the capital city. In abandonment and in dreaming, capital cities are especially exposed to latent forces of nature and of 'museumification'. These two forces created a tension that complicated attempts by King and Rockefeller to leave permanent architectural legacies in the signatures of their respective capitals.

  1. Research on a New Signature Scheme on Blockchain

    Directory of Open Access Journals (Sweden)

    Chao Yuan

    2017-01-01

    Full Text Available With the rise of Bitcoin, blockchain which is the core technology of Bitcoin has received increasing attention. Privacy preserving and performance on blockchain are two research points in academia and business, but there are still some unresolved issues in both respects. An aggregate signature scheme is a digital signature that supports making signatures on many different messages generated by many different users. Using aggregate signature, the size of the signature could be shortened by compressing multiple signatures into a single signature. In this paper, a new signature scheme for transactions on blockchain based on the aggregate signature was proposed. It was worth noting that elliptic curve discrete logarithm problem and bilinear maps played major roles in our signature scheme. And the security properties of our signature scheme were proved. In our signature scheme, the amount will be hidden especially in the transactions which contain multiple inputs and outputs. Additionally, the size of the signature on transaction is constant regardless of the number of inputs and outputs that the transaction contains, which can improve the performance of signature. Finally, we gave an application scenario for our signature scheme which aims to achieve the transactions of big data on blockchain.

  2. STRESS ANALYSIS IN CUTTING TOOLS COATED TiN AND EFFECT OF THE FRICTION COEFFICIENT IN TOOL-CHIP INTERFACE

    Directory of Open Access Journals (Sweden)

    Kubilay ASLANTAŞ

    2003-02-01

    Full Text Available The coated tools are regularly used in today's metal cutting industry. Because, it is well known that thin and hard coatings can reduce tool wear, improve tool life and productivity. Such coatings have significantly contributed to the improvements cutting economies and cutting tool performance through lower tool wear and reduced cutting forces. TiN coatings have especially high strength and low friction coefficients. During the cutting process, low friction coefficient reduce damage in cutting tool. In addition, maximum stress values between coating and substrate also decrease as the friction coefficient decreases. In the present study, stress analysis is carried out for HSS (High Speed Steel cutting tool coated with TiN. The effect of the friction coefficient between tool and chip on the stresses developed at the cutting tool surface and interface of coating and HSS is investigated. Damage zones during cutting process was also attempted to determine. Finite elements method is used for the solution of the problem and FRANC2D finite element program is selected for numerical solutions.

  3. Effects of momentum transfer on sizing of current collectors for lithium-ion batteries during laser cutting

    Science.gov (United States)

    Lee, Dongkyoung; Mazumder, Jyotirmoy

    2018-02-01

    One of the challenges of the lithium-ion battery manufacturing process is the sizing of electrodes with good cut surface quality. Poor cut surface quality results in internal short circuits in the cells and significant heat generation. One of the solutions that may improve the cut quality with a high cutting speed is laser cutting due to its high energy concentration, fast processing time, high precision, small heat affected zone, flexible range of laser power and contact free process. In order to utilize the advantages of laser electrode cutting, understanding the physical phenomena for each material is crucial. Thus, this study focuses on the laser cutting of current collectors, such as pure copper and aluminum. A 3D self-consistent mathematical model for the laser cutting, including fluid flow, heat transfer, recoil pressure, multiple reflections, capillary and thermo-capillary forces, and phase changes, is presented and solved numerically. Simulation results for the laser cutting are analyzed in terms of penetration time, depth, width, and absorptivity, based on these selected laser parameters. In addition, melt pool flow, melt pool geometry and temperature distribution are investigated.

  4. Deferment cutting in Appalachian hardwoods: the what, whys, and hows

    Science.gov (United States)

    H. Clay Smith; Gary W. Miller

    1991-01-01

    Deferment cutting is a regeneration practice that resembles a seed-tree or shelterwood cutting. The difference is that residual trees are not cut when the reproduction becomes established. Instead, residual trees are left until new reproduction matures to sawtimber size, and another regeneration cut is the silvicultural objective. Hence, with deferment cutting specific...

  5. Reachability cuts for the vehicle routing problem with time windows

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    2004-01-01

    This paper introduces a class of cuts, called reachability cuts, for the Vehicle Routing Problem with Time Windows (VRPTW). Reachability cuts are closely related to cuts derived from precedence constraints in the Asymmetric Traveling Salesman Problem with Time Windows and to k-path cuts...

  6. Lattice-Based Revocable Certificateless Signature

    Directory of Open Access Journals (Sweden)

    Ying-Hao Hung

    2017-10-01

    Full Text Available Certificateless signatures (CLS are noticeable because they may resolve the key escrow problem in ID-based signatures and break away the management problem regarding certificate in conventional signatures. However, the security of the mostly previous CLS schemes relies on the difficulty of solving discrete logarithm or large integer factorization problems. These two problems would be solved by quantum computers in the future so that the signature schemes based on them will also become insecure. For post-quantum cryptography, lattice-based cryptography is significant due to its efficiency and security. However, no study on addressing the revocation problem in the existing lattice-based CLS schemes is presented. In this paper, we focus on the revocation issue and present the first revocable CLS (RCLS scheme over lattices. Based on the short integer solution (SIS assumption over lattices, the proposed lattice-based RCLS scheme is shown to be existential unforgeability against adaptive chosen message attacks. By performance analysis and comparisons, the proposed lattice-based RCLS scheme is better than the previously proposed lattice-based CLS scheme, in terms of private key size, signature length and the revocation mechanism.

  7. Mining Eclipse for CrossCutting

    OpenAIRE

    Breu, Silvia; Zimmermann, Thomas; Lindig, Christian

    2007-01-01

    Software may contain functionality that does not align with its architecture. Such cross-cutting concerns do not exist from the beginning but emerge over time. By analysing where developers add code to a program, our history-based mining identifies cross-cutting concerns in a two-step process. First, we mine CVS archives for sets of methods where a call to a specific single method was added. In a second step, simple cross-cutting concerns are combined to complex cross-...

  8. Reconfigurable manufacturing execution system for pipe cutting

    Science.gov (United States)

    Yin, Y. H.; Xie, J. Y.

    2011-08-01

    This article presents a reconfigurable manufacturing execution system (RMES) filling the gap between enterprise resource planning and resource layer for pipe-cutting production with mass customisation and rapid adaptation to dynamic market, which consists of planning and scheduling layer and executive control layer. Starting from customer's task and process requirements, the cutting trajectories are planned under generalised mathematical model able to reconfigure in accordance with various intersecting types' joint, and all tasks are scheduled by nesting algorithm to maximise the utilisation rate of rough material. This RMES for pipe cutting has been effectively implemented in more than 100 companies.

  9. Cut elimination in multifocused linear logic

    DEFF Research Database (Denmark)

    Guenot, Nicolas; Brock-Nannestad, Taus

    2015-01-01

    We study cut elimination for a multifocused variant of full linear logic in the sequent calculus. The multifocused normal form of proofs yields problems that do not appear in a standard focused system, related to the constraints in grouping rule instances in focusing phases. We show that cut...... elimination can be performed in a sensible way even though the proof requires some specific lemmas to deal with multifocusing phases, and discuss the difficulties arising with cut elimination when considering normal forms of proofs in linear logic....

  10. Laser cutting with chemical reaction assist

    Science.gov (United States)

    Gettemy, Donald J.

    1992-01-01

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

  11. Emission noise and high frequency cut-off of the Kondo effect in a quantum dot

    Science.gov (United States)

    Delagrange, R.; Basset, J.; Bouchiat, H.; Deblock, R.

    2018-01-01

    By coupling on chip via a resonant circuit a carbon nanotube to a quantum noise detector, a superconductor-insulator-superconductor junction we measure the emission noise of a carbon nanotube quantum dot in the Kondo regime. The signature of the Kondo effect in the current noise is measured for different ratios of the Kondo temperature over the measured frequency and for different asymmetries of the coupling to the contacts and compared to finite frequency quantum noise calculations. Our results point towards the existence of a high frequency cut-off of the electronic emission noise associated with the Kondo resonance. This cut-off frequency is on the order of a few times the Kondo temperature when the electronic system is close to equilibrium, which is the case for a strongly asymmetric coupling. On the other hand, this cut-off is shifted to lower frequencies in a symmetric coupling situation where the bias voltage drives the Kondo state out of equilibrium. We then attribute the low frequency cut-off to voltage-induced spin relaxation.

  12. Periodic domain inversion in x-cut single-crystal lithium niobate thin film

    International Nuclear Information System (INIS)

    Mackwitz, P.; Rüsing, M.; Berth, G.; Zrenner, A.; Widhalm, A.; Müller, K.

    2016-01-01

    We report the fabrication of periodically poled domain patterns in x-cut lithium niobate thin-film. Here, thin films on insulator have drawn particular attention due to their intrinsic waveguiding properties offering high mode confinement and smaller devices compared to in-diffused waveguides in bulk material. In contrast to z-cut thin film lithium niobate, the x-cut geometry does not require back electrodes for poling. Further, the x-cut geometry grants direct access to the largest nonlinear and electro-optical tensor element, which overall promises smaller devices. The domain inversion was realized via electric field poling utilizing deposited aluminum top electrodes on a stack of LN thin film/SiO 2 layer/Bulk LN, which were patterned by optical lithography. The periodic domain inversion was verified by non-invasive confocal second harmonic microscopy. Our results show domain patterns in accordance to the electrode mask layout. The second harmonic signatures can be interpreted in terms of spatially, overlapping domain filaments which start their growth on the +z side.

  13. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    International Nuclear Information System (INIS)

    Gaffney, Jeffrey

    2012-01-01

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  14. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    Energy Technology Data Exchange (ETDEWEB)

    Gaffney, Jeffrey [Univ. of Arkansas, Little Rock, AR (United States)

    2012-12-12

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  15. Force Modulator System

    Energy Technology Data Exchange (ETDEWEB)

    Redmond Clark

    2009-04-30

    marry the die-specific Force Modulator technology with stamping presses in the form of a press cushion. This system would be designed to operate the binder ring for multiple parts, thus cutting the per-die cost of the technology. This study reports the results of technology field application. This project produced the following conclusions: (1) The Force Modulator system is capable of operating at very high tempos in the stamping environment; (2) The company can generate substantial, controlled holding tonnage (binder ring pressure) necessary to hold high strength steel parts for proper formation during draw operations; (3) A single system can be designed to operate with a family of parts, thus significantly reducing the per-die cost of a FM system; (4) High strength steel parts made with these systems appear to show significant quality improvements; (5) The amounts of steel required to make these parts is typically less than the amounts required with traditional blank-holding technologies; and (6) This technology will aid in the use of higher strength steels in auto and truck production, thus reducing weight and improving fuel efficiency.

  16. Topology and signature changes in braneworlds

    International Nuclear Information System (INIS)

    Gibbons, Gary W; Ishibashi, Akihiro

    2004-01-01

    It has been believed that topology and signature change of the universe can only happen accompanied by singularities, in classical, or instantons, in quantum, gravity. In this paper, we point out however that in the braneworld context, such an event can be understood as a classical, smooth event. We supply some explicit examples of such cases, starting from the Dirac-Born-Infeld action. Topology change of the brane universe can be realized by allowing self-intersecting branes. Signature change in a braneworld is made possible in an everywhere Lorentzian bulk spacetime. In our examples, the boundary of the signature change is a curvature singularity from the brane point of view, but nevertheless that event can be described in a completely smooth manner from the bulk point of view

  17. Biomarker Gene Signature Discovery Integrating Network Knowledge

    Directory of Open Access Journals (Sweden)

    Holger Fröhlich

    2012-02-01

    Full Text Available Discovery of prognostic and diagnostic biomarker gene signatures for diseases, such as cancer, is seen as a major step towards a better personalized medicine. During the last decade various methods, mainly coming from the machine learning or statistical domain, have been proposed for that purpose. However, one important obstacle for making gene signatures a standard tool in clinical diagnosis is the typical low reproducibility of these signatures combined with the difficulty to achieve a clear biological interpretation. For that purpose in the last years there has been a growing interest in approaches that try to integrate information from molecular interaction networks. Here we review the current state of research in this field by giving an overview about so-far proposed approaches.

  18. Selection signatures in worldwide sheep populations.

    Science.gov (United States)

    Fariello, Maria-Ines; Servin, Bertrand; Tosser-Klopp, Gwenola; Rupp, Rachel; Moreno, Carole; San Cristobal, Magali; Boitard, Simon

    2014-01-01

    The diversity of populations in domestic species offers great opportunities to study genome response to selection. The recently published Sheep HapMap dataset is a great example of characterization of the world wide genetic diversity in sheep. In this study, we re-analyzed the Sheep HapMap dataset to identify selection signatures in worldwide sheep populations. Compared to previous analyses, we made use of statistical methods that (i) take account of the hierarchical structure of sheep populations, (ii) make use of linkage disequilibrium information and (iii) focus specifically on either recent or older selection signatures. We show that this allows pinpointing several new selection signatures in the sheep genome and distinguishing those related to modern breeding objectives and to earlier post-domestication constraints. The newly identified regions, together with the ones previously identified, reveal the extensive genome response to selection on morphology, color and adaptation to new environments.

  19. A Methodology for Calculating Radiation Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Klasky, Marc Louis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilcox, Trevor [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bathke, Charles G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); James, Michael R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-01

    A rigorous formalism is presented for calculating radiation signatures from both Special Nuclear Material (SNM) as well as radiological sources. The use of MCNP6 in conjunction with CINDER/ORIGEN is described to allow for the determination of both neutron and photon leakages from objects of interest. In addition, a description of the use of MCNP6 to properly model the background neutron and photon sources is also presented. Examinations of the physics issues encountered in the modeling are investigated so as to allow for guidance in the user discerning the relevant physics to incorporate into general radiation signature calculations. Furthermore, examples are provided to assist in delineating the pertinent physics that must be accounted for. Finally, examples of detector modeling utilizing MCNP are provided along with a discussion on the generation of Receiver Operating Curves, which are the suggested means by which to determine detectability radiation signatures emanating from objects.

  20. Molecular Signature in HCV-Positive Lymphomas

    Directory of Open Access Journals (Sweden)

    Valli De Re

    2012-01-01

    Full Text Available Hepatitis C virus (HCV is a positive, single-stranded RNA virus, which has been associated to different subtypes of B-cell non-Hodgkin lymphoma (B-NHL. Cumulative evidence suggests an HCV-related antigen driven process in the B-NHL development. The underlying molecular signature associated to HCV-related B-NHL has to date remained obscure. In this review, we discuss the recent developments in this field with a special mention to different sets of genes whose expression is associated with BCR coupled to Blys signaling which in turn was found to be linked to B-cell maturation stages and NF-κb transcription factor. Even if recent progress on HCV-B-NHL signature has been made, the precise relationship between HCV and lymphoma development and phenotype signature remain to be clarified.

  1. Cryptanalysis of the arbitrated quantum signature protocols

    Energy Technology Data Exchange (ETDEWEB)

    Gao Fei; Qin Sujuan; Guo Fenzhuo; Wen Qiaoyan [State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2011-08-15

    As a new model for signing quantum messages, arbitrated quantum signature (AQS) has recently received a lot of attention. In this paper we study the cryptanalysis of previous AQS protocols from the aspects of forgery and disavowal. We show that in these protocols the receiver, Bob, can realize existential forgery of the sender's signature under known message attack. Bob can even achieve universal forgery when the protocols are used to sign a classical message. Furthermore, the sender, Alice, can successfully disavow any of her signatures by simple attack. The attack strategies are described in detail and some discussions about the potential improvements of the protocols are given. Finally we also present several interesting topics on AQS protocols that can be studied in future.

  2. A possible signature of annihilating dark matter

    Science.gov (United States)

    Chan, Man Ho

    2018-02-01

    In this article, we report a new signature of dark matter annihilation based on the radio continuum data of NGC 1569 galaxy detected in the past few decades. After eliminating the thermal contribution of the radio signal, an abrupt change in the spectral index is shown in the radio spectrum. Previously, this signature was interpreted as an evidence of convective outflow of cosmic ray. However, we show that the cosmic ray contribution is not enough to account for the observed radio flux. We then discover that if dark matter annihilates via the 4-e channel with the thermal relic cross-section, the electrons and positrons produced would emit a strong radio flux which can provide an excellent agreement with the observed signature. The best-fitting dark matter mass is 25 GeV.

  3. Cutting metals with a water jet

    International Nuclear Information System (INIS)

    Ehlbeck, U.; Corin, C.O.

    1986-01-01

    By the use of solid matter as additives in cutting tooths it is now also possible to cut metals (steel, high-alloy steel, titanium, aluminium, lead). The same standard high-pressure elements for the generation of a water jet are used to cut metals, glass, and ceramics. But within the tool the water jet first of all enters a mixer chamber where it takes in a predosed abrasive by the action of an injector. At the exit end of the mixer chamber, the jet is concentrated again. New applications of this 'Paser' system (particle-stream-erosion cutting process, a registered trade mark), which is also called abrasive jet process, are in aviation and space travel, nuclear technology and so forth. (orig./HP) [de

  4. Spending and cutting are two different worlds

    DEFF Research Database (Denmark)

    Houlberg, Kurt; Olsen, Asmus Leth; Pedersen, Lene Holm

    2016-01-01

    This article investigates politicians’ preferences for cutting and spending. The research questions are where do politicians prefer to cut, where do they prefer to spend and how is this influenced by political ideology? These questions are investigated in a large-scale survey experiment fielded...... to Danish local councillors, who are randomly assigned to a decision-making situation, where the block grant provided to their municipality is either increased or reduced. The results show that the politicians’ preferences for cutting and spending are asymmetric, in the sense that the policy areas, which...... are assigned the least cuts when the grant is reduced, are rarely the ones which are assigned extra money when the grant is increased. Areas with well-organised interests and a target group which is perceived as deserving are granted more money, whereas policy areas where the target group is perceived as less...

  5. Peripheral blood signatures of lead exposure.

    Directory of Open Access Journals (Sweden)

    Heather G LaBreche

    Full Text Available BACKGROUND: Current evidence indicates that even low-level lead (Pb exposure can have detrimental effects, especially in children. We tested the hypothesis that Pb exposure alters gene expression patterns in peripheral blood cells and that these changes reflect dose-specific alterations in the activity of particular pathways. METHODOLOGY/PRINCIPAL FINDING: Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in the peripheral blood of female Balb/c mice following exposure to per os lead acetate trihydrate or plain drinking water for two weeks and after a two-week recovery period. Data sets were RMA-normalized and dose-specific signatures were generated using established methods of supervised classification and binary regression. Pathway activity was analyzed using the ScoreSignatures module from GenePattern. CONCLUSIONS/SIGNIFICANCE: The low-level Pb signature was 93% sensitive and 100% specific in classifying samples a leave-one-out crossvalidation. The high-level Pb signature demonstrated 100% sensitivity and specificity in the leave-one-out crossvalidation. These two signatures exhibited dose-specificity in their ability to predict Pb exposure and had little overlap in terms of constituent genes. The signatures also seemed to reflect current levels of Pb exposure rather than past exposure. Finally, the two doses showed differential activation of cellular pathways. Low-level Pb exposure increased activity of the interferon-gamma pathway, whereas high-level Pb exposure increased activity of the E2F1 pathway.

  6. Automobile impact forces on concrete wall panels. Technical report

    International Nuclear Information System (INIS)

    Chiapetta, R.L.; Pang, E.C.

    1982-06-01

    The objective of this study was to develop force-time impact signature data for use in the design or evaluation of nuclear power plant structures subject to tornado-borne automotive vehicle impact. The approach was based on the use of analytical vehicle models to calculate imact forces. To assess the significance of vehicle/structure interaction for head-on impact force-histories, a lumped-mass model of a reinforced concrete wall panel was coupled to a one-dimensional vehicle model for numerous panel design configurations within the range of practical interest. Vehicle-structure interaction was found to have relatively little effect on the force histories

  7. Development of a tuneable channel cut crystal

    Science.gov (United States)

    Treimer, W.; Strobl, M.; Hilger, A.

    2001-10-01

    We have developed the first tuneable channel cut crystal for ultra small angle neutron scattering and neutron optical experiments. The Darwin range of a perfect crystal can be reduced down to a fraction of its natural width. This “Darwin reduction” was realised without any change of the beam geometry which yields an intensity gain relative to conventional asymmetric Bragg diffraction. With such tuneable channel cut crystal peaks nearly δ-peaks can experimentally be realised.

  8. Doppler Velocity Signatures of Idealized Elliptical Vortices

    Directory of Open Access Journals (Sweden)

    Wen-Chau Lee

    2006-01-01

    Full Text Available Doppler radar observations have revealed a class of atmospheric vortices (tropical cyclones, tornadoes, dust devils that possess elliptical radar reflectivity signatures. One famous example is Typhoon Herb (1996 that maintained its elliptical reflectivity structure over a 40-hour period. Theoretical work and dual-Doppler analyses of observed tropical cyclones have suggested two physical mechanisms that can explain the formation of two types of elliptical vortices observed in nature, namely, the combination of a circular vortex with either a wavenumber two vortex Rossby wave or a deformation field. The characteristics of these two types of elliptical vortices and their corresponding Doppler velocity signatures have not been previously examined.

  9. Cryptanalysis of the Quantum Group Signature Protocols

    Science.gov (United States)

    Zhang, Ke-Jia; Sun, Ying; Song, Ting-Ting; Zuo, Hui-Juan

    2013-11-01

    Recently, the researches of quantum group signature (QGS) have attracted a lot of attentions and some typical protocols have been designed for e-payment system, e-government, e-business, etc. In this paper, we analyze the security of the quantum group signature with the example of two novel protocols. It can be seen that both of them cannot be implemented securely since the arbitrator cannot solve the disputes fairly. In order to show that, some possible attack strategies, which can be used by the malicious participants, are proposed. Moreover, the further discussions of QGS are presented finally, including some insecurity factors and improved ideas.

  10. State of the Art: Signature Biometrics Verification

    Directory of Open Access Journals (Sweden)

    Nourddine Guersi

    2010-04-01

    Full Text Available This paper presents a comparative analysis of the performance of three estimation algorithms: Expectation Maximization (EM, Greedy EM Algorithm (GEM and Figueiredo-Jain Algorithm (FJ - based on the Gaussian mixture models (GMMs for signature biometrics verification. The simulation results have shown significant performance achievements. The test performance of EER=5.49 % for "EM", EER=5.04 % for "GEM" and EER=5.00 % for "FJ", shows that the behavioral information scheme of signature biometrics is robust and has a discriminating power, which can be explored for identity authentication.

  11. Dictionary of Large Hadron Collider Signatures

    CERN Document Server

    Belyaev, A; de Roeck, A; Godbole, R M; Mellado, B; Nyffeler, A; Petridou, C; Roy, D P

    2009-01-01

    We report on a plan to establish a "Dictionary of LHC Signatures", an initiative that started at the WHEPPX workshop in January 2008. This study aims towards the strategy on distinguishing of 3 classes of dark matter motivated scenarios such as R-parity conserved supersymmetry, Little Higgs models with T-parity conservation and Universal Extra Dimensions with KK-parity for generic cases of their realization in wide range of the model space. Discriminating signatures are tabulated and will need a further detailed analysis.

  12. Security problem on arbitrated quantum signature schemes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jeong Woon [Emerging Technology R and D Center, SK Telecom, Kyunggi 463-784 (Korea, Republic of); Chang, Ku-Young; Hong, Dowon [Cryptography Research Team, Electronics and Telecommunications Research Institute, Daejeon 305-700 (Korea, Republic of)

    2011-12-15

    Many arbitrated quantum signature schemes implemented with the help of a trusted third party have been developed up to now. In order to guarantee unconditional security, most of them take advantage of the optimal quantum one-time encryption based on Pauli operators. However, in this paper we point out that the previous schemes provide security only against a total break attack and show in fact that there exists an existential forgery attack that can validly modify the transmitted pair of message and signature. In addition, we also provide a simple method to recover security against the proposed attack.

  13. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Phillipp Brockmeyer

    2017-08-01

    Full Text Available Abstract Background The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs, modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Methods Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear® of the same thickness (1 mm were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. Results The horizontal (Fx and the vertical (Fz force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®, the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively. Conclusions RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  14. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor.

    Science.gov (United States)

    Brockmeyer, Phillipp; Kramer, Katharina; Böhrnsen, Florian; Gruber, Rudolf Matthias; Batschkus, Sarah; Rödig, Tina; Hahn, Wolfram

    2017-08-28

    The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs), modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear®) of the same thickness (1 mm) were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. The horizontal (Fx) and the vertical (Fz) force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®), the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively). RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  15. Development of cutting technique of magnetic alloys core

    International Nuclear Information System (INIS)

    Nomura, Masahiro; Tamura, Fumihiko; Schnase, Alexander; Yamamoto, Masanobu; Anami, Shozo; Ezura, Eizi; Hara, Keigo; Ohmori, Chihiro; Takagi, Akira; Yoshii, Masahito

    2005-01-01

    A new type of rf cavity using a high permeability magnetic alloy (MA) will be used for the J-PARC high intense proton synchrotrons. The cut core configuration has been adopted to get the optimum Q-value of MA core. We observed the cut surface of MA cores obtained by water jet and grind stone cut. The results show that the roughness of the cut surfaces by grind stone cut is much smaller than by water jet cut so that the cut core by grind stone cut has a possibility to reduce the temperature rise around the cut surface. We developed a grind stone cutting machine for large core and cut large cores by using this machine. High power test of those cores have been performed and we did not observe the temperature rise around the cut surface. (author)

  16. Dynamic Process Analysis In Cutting Zone During Machining Of Nickel Alloys

    Science.gov (United States)

    Czán, Andrej; Šajgalík, Michal; Martikáň, Anton; Mrázik, Jozef

    2015-12-01

    To generally improve effectivity of parts production and metal cutting process, there are used process models of super alloys together with finite element modeling simulations. Advanced measurement methods of the process could improve and verify the accuracy of these models. These methods cause many error sources when using empiric or exact methods such as infrared radiation thermography to measure the temperature distribution of the tool, workpiece, and chip during metal cutting. Measuring of metal machining is challenging due to factors such as the high magnification required, high surface speeds and deformations, micro-blackbody effects, changing emissivity and deformations present at metal cutting. As part of an ongoing effort to improve our understanding of uncertainties associated with these measurement methods, multimeasurement sets of experiments were performed. First set of measurements observed connection between surface temperature and the internal temperature of the cutting tool. This was accomplished by measuring the temperature using a thermal camera in cutting zone. Second set performed high-speed scan of dynamic processes such as formation of elastic and plastic deformation. During this operation was applied high-speed scannning system using macro conversion lens for monitoring of micro-structural changes in deformation areas. Next necessary applied set is recording of dynamic processes by implementation of piezoelectric measurement device for monitoring of cutting forces. The outputs from multimeasuring system are the basis for verification of theoretical knowledge from this field and elimination of uncertainties, which arise by using computer simulation systems.

  17. Laser cutting performances for thick steel specimens studied by molten metal removal conditions

    International Nuclear Information System (INIS)

    Tamura, Koji; Toyama, Shin'ichi

    2017-01-01

    Laser cutting performances for thick carbon steel and stainless steel specimens up to 300 mm in thickness were studied to dismantle large steel objects. The cutting performances were summarized based on the assist gas flow rate and the front kerf width, and the range for appropriate cutting conditions was shown. Gas pressure in the kerf region required for molten metal removal was estimated from the pressure loss on the kerf surface, which depended on the gas flow rate and the kerf width. The relation to keep sufficient gas pressure in the kerf well corresponded to the experimental relations for appropriate cutting. Drag force to the molten metal on the kerf surface was also estimated, which varied by the structures and materials. The behaviors such as cavity formation and its expansion in the kerf region at the unsuccessful cutting trials were well explained. The results are informative for the development of the laser cutting technology applied to the thick steel specimen for the nuclear decommissioning. (author)

  18. Properties and Cutting Performance of TiAlSiN Coating Prepared by Cathode Arc Ion Plating

    Science.gov (United States)

    Zhang, Er-Geng; Chen, Qiang; Wang, Qin-Xue; Huang, Biao

    2016-06-01

    TiAlSiN coating was deposited on high-speed steel (HSS) samples and cemented carbide tool inserts, respectively, by a new coating preparation procedure, and its properties and cutting performance were characterized. The coating thickness, chemical composition, microstructure morphology and mechanical properties were investigated by X-ray fluorescence measurement system, energy dispersive spectrometer (EDS), scanning electron microscope (SEM), nanoindentation, Rockwell hardness tester and ball-on-disc tribometer. A 3D orthogonal cutting experiment model was established by DEFORM-3D to study the influences of different coating thicknesses on cutting force and temperature, and the field cutting experiment was carried out. The results show that the thickness of TiAlSiN coating is 3.14μm prepared by the 3μm preparation procedure, microhardness is 36.727GPa with the Si content of about 5.22at.% as well as good fracture toughness and adhesion strength. The TC4 and AISI 1045 cutting tool inserts with 4μm coating thickness have the minimum cutting forces of about 734.7N and 450.7N, respectively. Besides, tool inserts with a thickness of 3μm have the minimum cutting temperatures of about 510.2∘C and 230.6∘C, respectively.

  19. Differences in neuromuscular strategies between landing and cutting tasks in female basketball and soccer athletes.

    Science.gov (United States)

    Cowley, Hanni R; Ford, Kevin R; Myer, Gregory D; Kernozek, Thomas W; Hewett, Timothy E

    2006-01-01

    High school female athletes are most likely to sustain a serious knee injury during soccer or basketball, 2 sports that often involve a rapid deceleration before a change of direction or while landing from a jump. To determine if female high school basketball and soccer players show neuromuscular differences during landing and cutting tasks and to examine neuromuscular differences between tasks and between dominant and nondominant sides. A 3-way mixed factorial design investigating the effects of sport (basketball, soccer), task (jumping, cutting), and side (dominant, nondominant). Laboratory. Thirty high school female athletes who listed either basketball or soccer as their only sport of participation (basketball: n = 15, age = 15.1 +/- 1.7 years, experience = 6.9 +/- 2.2 years, height = 165.3 +/- 7.9 cm, mass = 61.8 +/- 9.3 kg; soccer: n = 15, age = 14.8 +/- 0.8 years, experience = 8.8 +/- 2.5 years, height = 161.8 +/- 4.1 cm, mass = 54.6 +/- 7.6 kg). Ground reaction forces, stance time, valgus angles, and valgus moments were assessed during (1) a drop vertical jump with an immediate maximal vertical jump and (2) an immediate side-step cut at a 45 degrees angle. Basketball athletes had greater ground reaction forces (P vertical jump, whereas soccer players had greater ground reaction forces (P vertical jump. Greater valgus moments (P = .006) were noted on the dominant side during cutting. Our subjects demonstrated differences in ground reaction forces and stance times during 2 movements associated with noncontact anterior cruciate ligament injuries. Knee valgus moment and angle were significantly influenced by the type of movement performed. Sport-specific neuromuscular training may be warranted, with basketball players focusing on jumping and landing and soccer players focusing on unanticipated cutting maneuvers.

  20. Preliminarily measurement and analysis of sawing forces in fresh cadaver mandible using reciprocating saw for reality-based haptic feedback.

    Science.gov (United States)

    Yua, Dedong; Zhengb, Xiaohu; Chenc, Ming; Shend, Steve G F

    2012-05-01

    The aim of the study was to preliminarily measure and analyze the cutting forces in fresh Chinese cadaver mandible using a clinically widely used reciprocating saw for reality-based haptic feedback. Eight mandibles were taken from fresh Chinese cadavers, 4 females and 4 males, aged between 59 and 95 years. A set of sawing experiments, using a surgery Stryker micro-reciprocating saw and Kistler piezoelectric dynamometer, was carried out by a CNC machining center. Under different vibration frequencies of saw and feeding rates measured from orthognathic surgery, sawing forces were recorded by a signal acquisition system. Remarkably different sawing forces were measured from different cadavers. Feed and vibration frequency of the reciprocating saw could determine the cutting forces only on 1 body. To reduce the impact of bone thickness changes on the cutting force measurements, all the cutting force data should be converted to the force of unit cutting length. The vibration frequency of haptic feedback system is determined by main cutting forces. Fast Fourier transform method can be used to calculate the frequency of this system. To simulate surgery in higher fidelity, all the sawing forces from the experiment should be amended by experienced surgeons before use in virtual reality surgery simulator. Sawing force signals of different ages for force feedback were measured successfully, and more factors related to the bone mechanical properties, such as bone density, should be concerned in the future.

  1. A group signature scheme based on quantum teleportation

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xiaojun; Tian Yuan; Ji Liping; Niu Xiamu, E-mail: wxjun36@gmail.co [Information Countermeasure Technique Research Institute, Harbin Institute of Technology, Harbin 150001 (China)

    2010-05-01

    In this paper, we present a group signature scheme using quantum teleportation. Different from classical group signature and current quantum signature schemes, which could only deliver either group signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Security analysis proved that our scheme has the characteristics of group signature, non-counterfeit, non-disavowal, blindness and traceability. Our quantum group signature scheme has a foreseeable application in the e-payment system, e-government, e-business, etc.

  2. COMPUTER-IMPLEMENTED METHOD OF PERFORMING A SEARCH USING SIGNATURES

    DEFF Research Database (Denmark)

    2017-01-01

    A computer-implemented method of processing a query vector and a data vector), comprising: generating a set of masks and a first set of multiple signatures and a second set of multiple signatures by applying the set of masks to the query vector and the data vector, respectively, and generating...... candidate pairs, of a first signature and a second signature, by identifying matches of a first signature and a second signature. The set of masks comprises a configuration of the elements that is a Hadamard code; a permutation of a Hadamard code; or a code that deviates from a Hadamard code...

  3. Coriolis Force

    Science.gov (United States)

    Marciuc, Daly; Solschi, Viorel

    2017-04-01

    Understanding the Coriolis effect is essential for explaining the movement of air masses and ocean currents. The lesson we propose aims to familiarize students with the manifestation of the Coriolis effect. Students are guided to build, using the GeoGebra software, a simulation of the motion of a body, related to a rotating reference system. The mathematical expression of the Coriolis force is deduced, for particular cases, and the Foucault's pendulum is presented and explained. Students have the opportunity to deepen the subject, by developing materials related to topics such as: • Global Wind Pattern • Ocean Currents • Coriolis Effect in Long Range Shooting • Finding the latitude with a Foucault Pendulum

  4. Joining Forces

    DEFF Research Database (Denmark)

    Christiansen, Anne Mette

    2013-01-01

    The interest in Corporate Social Responsibility (CSR) has grown dramatically over the last three years in Greenland. A vast geographical area with a tiny population, Greenland has recently obtained self-government status and is going through a rapid development economically and socially...... as the country moves towards embracing extractive industries (oil, gas and mining) as a path to development. Both government, civil society and business are increasingly looking for new and innovative ways of joining forces across sectors to solve some of the country's many critical social issues. Greenlandic...... companies have over the last 23 years embraced the concept of strategic CSR and are increasingly engaging in cross-sector partnerships as part of their CSR strategy. The partnerships take different forms both in regards to number of partners, focus areas and level of strategic engagement. In the article...

  5. Under water cutting of metallic materials by laser

    International Nuclear Information System (INIS)

    Jha, S.K.; Ghosal, Swati; Goswami, G.L.

    1994-01-01

    A laser cutting assembly has been made which allows laser beam to be focused on a job submerged under water, even though the laser head remains outside water. Under water cutting will be very useful for cutting of radioactive materials inside pool or storage bay. This can also be used for reactive materials like uranium etc which otherwise are difficult to cut in open atmosphere as they catch fire. The effect of cutting parameters on the cut quality and also comparison between under-water cutting and open air-cutting is discussed. (author). 2 refs., 1 tab

  6. Cutting meat with bone using an ultrahigh pressure abrasive waterjet.

    Science.gov (United States)

    Wang, J; Shanmugam, D K

    2009-04-01

    An experimental study of abrasive waterjet (AWJ) cutting of beef, pork and lamb meat with and without bone is presented. Salt particles were used as the abrasives. It has been found that an AWJ could significantly increase the depth of cut with much improved cut quality in cutting pure meat as compared to plain (or pure) waterjet cutting, while a plain waterjet was incapable of cutting bone satisfactorily. The study shows that AWJ cutting produced a very narrow kerf of less than 1mm and hence resulted in mush less meat loss than the traditional cutting processes, and meat can be cut at room temperature to eliminate the freezing or chilling costs. It is shown that a traverses speed of 20mm/s can be used to cut through 44mm thick beef rib bones with good cut quality. When slicing pure meat of 150mm thickness, the traverse speed of 66.67mm/s can yield very good cut quality. It is suggested that AWJ cutting is a viable technology for meat cutting. Plausible trends for the depth of cut, cutting rate and cut quality with respect to the process variables are discussed. Recommendations are finally made for the selection of the most appropriate process parameters for cutting meat of a given thickness.

  7. Naval S and T Strategy: Innovations for the Future Force

    Science.gov (United States)

    2015-01-20

    to harvest S&T investments made years ago to speed development of cutting -edge technologies like railguns, lasers, new radars and autonomous...Vision: Cutting -edge scientific research and technology provides decisive technological advantage and influence for our naval forces. The naval S&T... waterjets aimed at staving off rudder and propeller damage experienced on high-speed ships. The new Axial-Flow Waterjet Mk-1, developed as an FNC, can

  8. Laser cutting of various materials: Kerf width size analysis and life cycle assessment of cutting process

    Science.gov (United States)

    Yilbas, Bekir Sami; Shaukat, Mian Mobeen; Ashraf, Farhan

    2017-08-01

    Laser cutting of various materials including Ti-6Al-4V alloy, steel 304, Inconel 625, and alumina is carried out to assess the kerf width size variation along the cut section. The life cycle assessment is carried out to determine the environmental impact of the laser cutting in terms of the material waste during the cutting process. The kerf width size is formulated and predicted using the lump parameter analysis and it is measured from the experiments. The influence of laser output power and laser cutting speed on the kerf width size variation is analyzed using the analytical tools including scanning electron and optical microscopes. In the experiments, high pressure nitrogen assisting gas is used to prevent oxidation reactions in the cutting section. It is found that the kerf width size predicted from the lump parameter analysis agrees well with the experimental data. The kerf width size variation increases with increasing laser output power. However, this behavior reverses with increasing laser cutting speed. The life cycle assessment reveals that material selection for laser cutting is critical for the environmental protection point of view. Inconel 625 contributes the most to the environmental damages; however, recycling of the waste of the laser cutting reduces this contribution.

  9. Piezoelectric sensor pen for dynamic signature verification

    Energy Technology Data Exchange (ETDEWEB)

    EerNisse, E.P.; Land, C.E.; Snelling, J.B.

    1977-01-01

    The concept of using handwriting dynamics for electronic identification is discussed. A piezoelectric sensor pen for obtaining the pen point dynamics during writing is described. Design equations are derived and details of an operating device are presented. Typical output waveforms are shown to demonstrate the operation of the pen and to show the dissimilarities between dynamics of a genuine signature and an attempted forgery.

  10. Signatures of mutational processes in human cancer

    NARCIS (Netherlands)

    Alexandrov, Ludmil B.; Nik-Zainal, Serena; Wedge, David C.; Aparicio, Samuel A. J. R.; Behjati, Sam; Biankin, Andrew V.; Bignell, Graham R.; Bolli, Niccolò; Borg, Ake; Børresen-Dale, Anne-Lise; Boyault, Sandrine; Burkhardt, Birgit; Butler, Adam P.; Caldas, Carlos; Davies, Helen R.; Desmedt, Christine; Eils, Roland; Eyfjörd, Jórunn Erla; Foekens, John A.; Greaves, Mel; Hosoda, Fumie; Hutter, Barbara; Ilicic, Tomislav; Imbeaud, Sandrine; Imielinsk, Marcin; Jäger, Natalie; Jones, David T. W.; Jones, David; Knappskog, Stian; Kool, Marcel; Lakhani, Sunil R.; López-Otín, Carlos; Martin, Sancha; Munshi, Nikhil C.; Nakamura, Hiromi; Northcott, Paul A.; Pajic, Marina; Papaemmanuil, Elli; Paradiso, Angelo; Pearson, John V.; Puente, Xose S.; Raine, Keiran; Ramakrishna, Manasa; Richardson, Andrea L.; Richter, Julia; Rosenstiel, Philip; Schlesner, Matthias; Schumacher, Ton N.; Span, Paul N.; Teague, Jon W.; Totoki, Yasushi; Tutt, Andrew N. J.; Valdés-Mas, Rafael; van Buuren, Marit M.; van 't Veer, Laura; Vincent-Salomon, Anne; Waddell, Nicola; Yates, Lucy R.; Zucman-Rossi, Jessica; Futreal, P. Andrew; McDermott, Ultan; Lichter, Peter; Meyerson, Matthew; Grimmond, Sean M.; Siebert, Reiner; Campo, Elías; Shibata, Tatsuhiro; Pfister, Stefan M.; Campbell, Peter J.; Stratton, Michael R.; Claviez, Alexander; Rosenwald, Andreas; Borkhardt, Arndt; Brors, Benedikt; Radlwimmer, Bernhard; Lawerenz, Chris; Lopez, Cristina; Langenberger, David; Karsch, Dennis; Lenze, Dido; Kube, Dieter; Leich, Ellen; Richter, Gesine; Korbel, Jan; Hoell, Jessica; Eils, Jürgen; Hezaveh, Kebriah; Trümper, Lorenz; Rosolowski, Maciej; Weniger, Marc; Rohde, Marius; Kreuz, Markus; Loeffler, Markus; Schilhabel, Markus; Dreyling, Martin; Hansmann, Martin-Leo; Hummel, Michael; Szczepanowski, Monika; Ammerpohl, Ole; Stadler, Peter F.; Möller, Peter; Küppers, Ralf; Haas, Siegfried; Eberth, Sonja; Schreiber, Stefan; Bernhart, Stephan H.; Hoffmann, Steve; Radomski, Sylwester; Kostezka, Ulrike; Klapper, Wolfram; Sotiriou, Christos; Larsimont, Denis; Vincent, Delphine; Maetens, Marion; Mariani, Odette; Sieuwerts, Anieta M.; Martens, John W. M.; Jonasson, Jon G.; Treilleux, Isabelle; Thomas, Emilie; Mac Grogan, Gaëtan; Mannina, Cécile; Arnould, Laurent; Burillier, Laura; Merlin, Jean-Louis; Lefebvre, Magali; Bibeau, Frédéric; Massemin, Blandine; Penault-Llorca, Frédérique; Lopez, Qian; Mathieu, Marie-Christine; Lonning, Per Eystein; Schlooz-Vries, Margrete; Tol, Jolien; van Laarhoven, Hanneke; Sweep, Fred; Bult, Peter

    2013-01-01

    All cancers are caused by somatic mutations; however, understanding of the biological processes generating these mutations is limited. The catalogue of somatic mutations from a cancer genome bears the signatures of the mutational processes that have been operative. Here we analysed 4,938,362

  11. Characteristics of small boat acoustic signatures

    Science.gov (United States)

    Barlett, Martin L.; Wilson, Gary R.

    2002-11-01

    Small boats are often a dominant noise source in harbors, coastal regions, and lakes. However, detailed information about acoustic characteristics is not generally available. To remedy this deficiency, measurements of underwater acoustic signatures from various small boats have been conducted under controlled conditions. Boats used in the measurements were powered by a variety of gasoline and diesel motors in outboard, inboard-outboard, and inboard drive configurations. Measurements were made using a bottom mounted hydrophone in about 100 feet of water. In many instances, the boats were instrumented with a system that recorded the GPS position and engine RPM permitting accurate determinations of platform operating parameters. Measured small boat signatures contain both narrowband and broadband acoustic components. Narrowband components are generally associated with sources from the engine or drive. Narrowband levels in the observed spectra were found to exhibit significant variations and are believed to originate from fluctuations in the load on the engine and drive. Broadband energy was observed to be a dominant noise source at frequencies above several hundred Hertz and is a characteristic feature in all small boat signatures. Examples of small boat signatures will be presented and representative acoustic characteristics of this type of watercraft will be discussed.

  12. Photospheric, Chromospheric and Helioseismic Signatures of a ...

    Indian Academy of Sciences (India)

    2003-10-26

    Oct 26, 2003 ... since the beginning of routine TSI measurements in 1978 (Woods et al. 2004). We have selected this flare for detailed analysis of its photospheric, chromospheric and helioseismic signatures due to the favourable location of the active region near the. CMP which minimizes the projection effects. 2.

  13. CERN Member States signatures at LEP inauguration

    CERN Multimedia

    1989-01-01

    The signatures of the dignitaries who represented CERN's Member States on the occasion of the Inauguration of LEP on 13 November 1989. The Large Electron-Positron (LEP) collider was inaugurated in the presence of some 1500 guests, including Heads of State and Ministers from all of CERN's 14 Member States.

  14. The Pedagogic Signature of Special Needs Education

    Science.gov (United States)

    Weiß, Sabine; Kollmannsberger, Markus; Lerche, Thomas; Oubaid, Viktor; Kiel, Ewald

    2014-01-01

    The goal of the following study is to identify a pedagogic signature, according to LS Shulman, for working with students who have special educational needs. Special educational needs are defined as significant limitations in personal development and learning which require particular educational measures beyond regular education. The development of…

  15. Dictionary of Large Hadron Collider signatures

    Indian Academy of Sciences (India)

    We report on a plan to establish a `Dictionary of LHC Signatures', an initiative that started at the WHEPP-X workshop in Chennai, January 2008. This study aims at the strategy of distinguishing 3 classes of dark matter motivated scenarios such as -parity conserved supersymmetry, little Higgs models with -parity ...

  16. Practical Certificateless Aggregate Signatures From Bilinear Maps

    NARCIS (Netherlands)

    Gong, Zheng; Long, Yu; Hong, Xuan; Chen, Kefei

    2008-01-01

    In some restrictive environments, such as sensor networks, each sensor submits the newest information to the server, every message must be authenticated to immune forgery and replay attacks. But the regular signatures need to be saved and verified individually, which will heavily add the costs of

  17. Detection of proteolytic signatures for Parkinson's disease

    DEFF Research Database (Denmark)

    Jordal, Peter Lüttge; Dyrlund, Thomas F.; Winge, Kristian

    2016-01-01

    Aim: To investigate if idiopathic Parkinson's disease (IPD) is associated with distinct proteolytic signatures relative to non-neurodegenerative controls (NND) and patients with multiple system atrophy (MSA). Materials & methods: A subtiligase-based N-terminomics screening method was exploited...

  18. Ankle and Other Signatures in Uhecr

    Science.gov (United States)

    Berezinsky, Veniamin

    2015-03-01

    The interaction signatures of UHE protons propagating through CMB are discussed. Much attention is given to ankle, which starting from 1963 is usually interpreted as a feature of transition from galactic to extragalactic cosmic rays. We argue here that this interpretation is now excluded. It gives more credit to alternative explanation of the ankle as an intrinsic part of the pair-production dip.

  19. SUSY with ATLAS Leptonic Signatures, Coannihilation Region

    CERN Document Server

    Comune, G

    2004-01-01

    In this work we present an initial study on how leptonic signatures can be used at ATLAS to constrain SUSY particle masses combinations for the first time in the so called "coannihilation region''. The analysis is carried out in the framework of mSUGRA constrained SUSY model using fast detector simulation and reconstruction exploiting an invariant mass endpoint technique.

  20. Comparison of metagenomic samples using sequence signatures

    Directory of Open Access Journals (Sweden)

    Jiang Bai

    2012-12-01

    Full Text Available Abstract Background Sequence signatures, as defined by the frequencies of k-tuples (or k-mers, k-grams, have been used extensively to compare genomic sequences of individual organisms, to identify cis-regulatory modules, and to study the evolution of regulatory sequences. Recently many next-generation sequencing (NGS read data sets of metagenomic samples from a variety of different environments have been generated. The assembly of these reads can be difficult and analysis methods based on mapping reads to genes or pathways are also restricted by the availability and completeness of existing databases. Sequence-signature-based methods, however, do not need the complete genomes or existing databases and thus, can potentially be very useful for the comparison of metagenomic samples using NGS read data. Still, the applications of sequence signature methods for the comparison of metagenomic samples have not been well studied. Results We studied several dissimilarity measures, including d2, d2* and d2S recently developed from our group, a measure (hereinafter noted as Hao used in CVTree developed from Hao’s group (Qi et al., 2004, measures based on relative di-, tri-, and tetra-nucleotide frequencies as in Willner et al. (2009, as well as standard lp measures between the frequency vectors, for the comparison of metagenomic samples using sequence signatures. We compared their performance using a series of extensive simulations and three real next-generation sequencing (NGS metagenomic datasets: 39 fecal samples from 33 mammalian host species, 56 marine samples across the world, and 13 fecal samples from human individuals. Results showed that the dissimilarity measure d2S can achieve superior performance when comparing metagenomic samples by clustering them into different groups as well as recovering environmental gradients affecting microbial samples. New insights into the environmental factors affecting microbial compositions in metagenomic samples