Sample records for temperature joint analysis

  1. Joint analysis of changes in temperature and precipitation on the Loess Plateau during the period 1961-2011 (United States)

    Miao, Chiyuan; Sun, Qiaohong; Duan, Qingyun; Wang, Yafeng


    The Loess Plateau is particularly sensitive to climate change owing to its fragile ecological environment and geographic features. Here, we present a comprehensive analysis of the joint probabilistic characteristics and tendencies for bivariate and trivariate precipitation and temperature indices across the plateau, based on copula theory. The results show that the southeast region of the plateau had a higher potential for flooding: the 10-year return levels for the number of days with heavy and very heavy precipitation (R10mm, R20mm) and for the maximum 5-day precipitation value (RX5day) were higher in this region. The northwest region of the plateau, however, had a higher potential for drought, as reflected in the high and increasing 10-year return levels for the number of consecutive dry days (CDD) and the number of days with low precipitation (R1mm). In a joint analysis of precipitation indices, large areas of the Loess Plateau showed a relatively high risk of concurrent extreme precipitation events. However, the risk of concurrent extreme wet and dry events did not increase over the past half century, as demonstrated by nonsignificant changes in the probability of concurrently long CDD and long consecutive wet days (CWD). A trivariate copula analysis showed that some grid locations in the southeast of the plateau had an increasing risk of extreme precipitation events occurring at a high frequency and a high intensity, and forming a large percentage of the annual precipitation. Joint analysis of precipitation and temperature indices showed that the risk of higher temperatures and longer spells of consecutive dry days had increased over the past 50 years in grid locations scattered in the northern and southern regions: there were negative trends in the bivariate return periods for warm days (TX90p) and CDD. In addition, there was a decreased probability of concurrent long spells of consecutive wet days and colder temperatures, as demonstrated by the positive

  2. High temperature strength analysis of welded joint of RAF's by small punch test

    Energy Technology Data Exchange (ETDEWEB)

    Kato, T. [Muroran Institute of Technology, Dept. of Materials Science and Engineeering, Hokkaido (Japan); Komazaki, S.; Kohno, Y. [Muroran Institute of Technology, Muroran (Japan); Tanigawa, H. [Japan Atomic Energy Agency, Naga-gun, Ibaraki-ken (Japan); Kohyama, A. [Kyoto Univ., Institute of Advanced Energy (Japan)


    Full text of publication follows: Nucleation and growth of microvoids and/or small cracks in fine-grained heat affected zone (HAZ) after long-term service operation, which is recognized as Type IV creep damage, has recently been a worldwide issue for high Cr ferritic steels. In our group, a small punch (SP) creep test has been successfully applied to evaluate this damage of low alloy ferritic steel. However, the HAZ of fusion reactor material welded by electron-beam (EB) welding is so narrow that it is not easy to evaluate its mechanical properties by conventional tests including the SP creep test with a plate-type specimen (10 x 10 x 0.5 mm{sup 3}). In this study, the SP creep test using a further miniaturized specimen was developed and applied to the welded joint of reduced activation ferritic steels (RAFs), F82H-IEA (Fe-8Cr-2W-0.2V-0.02Ta), for measuring creep properties of the HAZ. For the SP creep test, TEM disk-type samples (diam. 3.0 x 0.30 mm) were removed from the base metal (BM), weld metal (WM) and HAZ, respectively. The specimen surfaces were polished up to a 0.05 {mu}m alumina powder finish and the specimen's thickness was finally adjusted to 0.25 mm. The SP creep tests were performed at temperatures of 823{approx}973 K and under loads ranging from 20 to 200 N. A constant load was applied to the center of the specimen through the Si{sub 3}N{sub 4} bail (diam. 1.0 mm) using the electric servo motor. The central deflection of the specimen was monitored by measuring the displacement of the compression rod. The tests were carried out in an argon gas atmosphere and the gas was continuously passed through during the test to prevent severe oxidation of the specimen. The differences in SP creep properties such as rupture time and minimum creep rate between the BM, WM and HAZ were discussed in terms of microstructural changes during welding thermal cycles. In addition, the result obtained from the BM was correlated with those of uniaxial creep test

  3. Statistical Analysis and Prediction on Tensile Strength of 316L-SS Joints at High Temperature Based on Weibull Distribution (United States)

    An, Z. L.; Chen, T.; Cheng, D. L.; Chen, T. H.; Y Wang, Z.


    In this work, the prediction on average tensile strength of 316L stainless steel is statistically analyzed by Weibull distribution method. Direct diffusion bonding of 316L-SS was performed at high temperature of 550°C and 8 tension tests were carried out. The results obtained vary between 87.8MPa and 160.8MPa. The probability distribution of material failure is obtained by using the Weibull distribution.

  4. Low temperature aluminum soldering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Peterkort, W.G.


    The investigation of low temperature aluminum soldering included the collection of spread factor and dihedral angle data for several solder alloys and a study of flux effects on aluminum. Selected solders were subjected to environmental tests and evaluated on the basis of tensile strength, joint resistance, visual appearance, and metallurgical analysis. A production line method for determining adequate flux removal was developed.

  5. Reusable Solid Rocket Motor Nozzle Joint-4 Thermal Analysis (United States)

    Clayton, J. Louie


    This study provides for development and test verification of a thermal model used for prediction of joint heating environments, structural temperatures and seal erosions in the Space Shuttle Reusable Solid Rocket Motor (RSRM) Nozzle Joint-4. The heating environments are a result of rapid pressurization of the joint free volume assuming a leak path has occurred in the filler material used for assembly gap close out. Combustion gases flow along the leak path from nozzle environment to joint O-ring gland resulting in local heating to the metal housing and erosion of seal materials. Analysis of this condition was based on usage of the NASA Joint Pressurization Routine (JPR) for environment determination and the Systems Improved Numerical Differencing Analyzer (SINDA) for structural temperature prediction. Model generated temperatures, pressures and seal erosions are compared to hot fire test data for several different leak path situations. Investigated in the hot fire test program were nozzle joint-4 O-ring erosion sensitivities to leak path width in both open and confined joint geometries. Model predictions were in generally good agreement with the test data for the confined leak path cases. Worst case flight predictions are provided using the test-calibrated model. Analysis issues are discussed based on model calibration procedures.

  6. Tensile Strength of Finger Joints at Elevated Temperatures

    DEFF Research Database (Denmark)

    Nielsen, Peter C.; Olesen, Frits Bolonius

    A series of test s aimed a t establishing the effect of temperature upon the tensile strength parallel-to-grain of finger jointed laminae for glulam has been conducted in the Fire Research Laboratory at Aalborg University Centre. The objective of this report is to present the background...

  7. Analysis of Joint Ventures Financial State

    Directory of Open Access Journals (Sweden)

    Alla V. Dmitrenko


    Full Text Available The article describes the basic techniques for the analysis of businesses financial state and methods that were adapted for the joint ventures activities, analyses joint venture financial state, makes conclusions and submits reasonable proposals for improvement of its future activities

  8. Delamination failure of multilaminated adhesively bonded joints at low temperatures (United States)

    Lee, Chi-Seung; Chun, Min-Sung; Kim, Myung-Hyun; Lee, Jae-Myung


    A series of experimental investigations of multilaminated joints adhesively bonded by epoxy/polyurethane (PU) glue were conducted in order to examine the delamination failure characteristics under in-plane shear loading at low temperatures. In order to observe these phenomena, a series of lap-shear tests were carried out at various low temperatures (20 °C, -110 °C and -163 °C) and various adhesion areas (15 mm × 50 mm, 30 mm × 50 mm, 50 mm × 50 mm, 75 mm × 50 mm and 100 mm × 50 mm). The test results were used to investigate the delamination and material characteristics, as well as the material properties, e.g., ultimate shear stress and shear elongation. Furthermore, the dependencies of the characteristics of multilaminated adhesively bonded joints (MABJs) on temperature and adhesion area was analyzed using the stress-strain relationship, and closed form formulas that are functions of the dependent parameters are proposed.

  9. Knee joint vibroarthrographic signal processing and analysis

    CERN Document Server

    Wu, Yunfeng


    This book presents the cutting-edge technologies of knee joint vibroarthrographic signal analysis for the screening and detection of knee joint injuries. It describes a number of effective computer-aided methods for analysis of the nonlinear and nonstationary biomedical signals generated by complex physiological mechanics. This book also introduces several popular machine learning and pattern recognition algorithms for biomedical signal classifications. The book is well-suited for all researchers looking to better understand knee joint biomechanics and the advanced technology for vibration arthrometry. Dr. Yunfeng Wu is an Associate Professor at the School of Information Science and Technology, Xiamen University, Xiamen, Fujian, China.

  10. Analysis of the Joint Link between Extreme Temperatures, Precipitation and Climate Indices in Winter in the Three Hydroclimate Regions of Southern Quebec

    Directory of Open Access Journals (Sweden)

    Ali A. Assani


    Full Text Available We analyze the relationship between four climate variables (maximum and minimum extreme temperatures, rainfall and snowfall measured in winter (December to March at 17 stations from 1950 to 2000 in the three hydroclimate regions of southern Quebec, and six seasonal climate indices using canonical correlation analysis (CCA and the copula method. This analysis yielded these major results: (1 extreme temperatures are not correlated with the amount of winter rain or snow in southern Quebec; (2 winter seasonal climate indices show better correlations with climate variables than do fall climate indices; (3 winter extreme temperatures are best correlated (positive correlation with the Atlantic Multidecadal Oscillation (AMO in the eastern region, but show a negative correlation with the Arctic Oscillation (AO in the southwestern region; (4 the total amount of winter snow is best correlated (negative correlation with the Pacific Decadal Oscillation (PDO in the three hydroclimate regions; (5 the total amount of winter rain is best (negatively correlated with PDO in the eastern region, but shows a positive correlation with AO in the southeast region. Finally, the copula method revealed very little change in the dependence between climate indices and climate variables in the three hydroclimate regions.

  11. Analysis of NSTX TF Joint Voltage Measurements

    Energy Technology Data Exchange (ETDEWEB)

    R, Woolley


    This report presents findings of analyses of recorded current and voltage data associated with 72 electrical joints operating at high current and high mechanical stress. The analysis goal was to characterize the mechanical behavior of each joint and thus evaluate its mechanical supports. The joints are part of the toroidal field (TF) magnet system of the National Spherical Torus Experiment (NSTX) pulsed plasma device operating at the Princeton Plasma Physics Laboratory (PPPL). Since there is not sufficient space near the joints for much traditional mechanical instrumentation, small voltage probes were installed on each joint and their voltage monitoring waveforms have been recorded on sampling digitizers during each NSTX ''shot''.

  12. Structural dynamic analysis of a ball joint (United States)

    Hwang, Seok-Cheol; Lee, Kwon-Hee


    Ball joint is a rotating and swiveling element that is typically installed at the interface between two parts. In an automobile, the ball joint is the component that connects the control arms to the steering knuckle. The ball joint can also be installed in linkage systems for motion control applications. This paper describes the simulation strategy for a ball joint analysis, considering manufacturing process. Its manufacturing process can be divided into plugging and spinning. Then, the interested responses is selected as the stress distribution generated between its ball and bearing. In this paper, a commercial code of NX DAFUL using an implicit integration method is introduced to calculate the response. In addition, the gap analysis is performed to investigate the fitness, focusing on the response of the displacement of a ball stud. Also, the optimum design is suggested through case studies.





    The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points c...

  14. Mechanical Characterization of Adhesive Bonded Sheet Metal Joints at Elevated Temperature (United States)

    Mori, Kiyomi; Azimin, Muhd; Tanaka, Masashi; Ikeda, Takashi

    A new approach is expected for heat resisting metal joints with inorganic adhesive. In the present study, the mechanical characterization of the inorganic adhesive and the strength evaluation of metal joints are realized by an experimental procedure that includes a static test for single lap joints bonded with inorganic adhesives. The inorganic adhesive can be cured at 150°C, and the maximum temperature resistance proposed is up to 1,200°C. A tensile shear test for the joints with a nickel adherend is performed at an elevated temperature of up to 400°C. The effect of material property, overlap length, and thickness of adherend on the joint strength is discussed based on stress analysis for corresponding joint models using a Finite Element Method. It is important to confirm whether fracture occurred in the adhesive layer or at the interface between the adhesive and the adherend. Therefore, the deformation and fracture behavior of the adhesive layer is investigated microscopically by the photographs of a scanning electron microscope (SEM) for the fracture surface.

  15. Elevated temperature deformation analysis (United States)

    Nelson, J. M.

    The paper demonstrates a novel nondestructive test and data analysis technique for quantitative measurement of circumferentially varying flexural moduli of 2D involute carbon-carbon tag rings containing localized wrinkles and dry plies at room and rocket nozzle operating temperatures. Room temperature computed tomography (CT) deformation tests were performed on 11 carbon-carbon rings selected from the cylinders and cones fabricated under the NDE data application program and two plexiglass rings fabricated under this program. This testing and analysis technique is found to have primary application in validation of analytical models for carbon-carbon performance modeling. Both effects of defects assumptions, the effects of high temperature environments, and failure-related models can be validated effectively. The testing and analysis process can be interwoven in a manner that increases the engineering understanding of the material behavior and permits rapid resolution of analysis questions. Specific recommendations for the development and implementation of this technique are provided.

  16. Joint data analysis in nutritional epidemiology

    DEFF Research Database (Denmark)

    Pinart, Mariona; Nimptsch, Katharina; Bouwman, Jildau


    Background: Joint data analysis from multiple nutrition studies may improve the ability to answer complex questions regarding the role of nutritional status and diet in health and disease. Objective: The objective was to identify nutritional observational studies from partners participating in th...

  17. Joint multifractal analysis based on wavelet leaders (United States)

    Jiang, Zhi-Qiang; Yang, Yan-Hong; Wang, Gang-Jin; Zhou, Wei-Xing


    Mutually interacting components form complex systems and these components usually have long-range cross-correlated outputs. Using wavelet leaders, we propose a method for characterizing the joint multifractal nature of these long-range cross correlations; we call this method joint multifractal analysis based on wavelet leaders (MF-X-WL). We test the validity of the MF-X-WL method by performing extensive numerical experiments on dual binomial measures with multifractal cross correlations and bivariate fractional Brownian motions (bFBMs) with monofractal cross correlations. Both experiments indicate that MF-X-WL is capable of detecting cross correlations in synthetic data with acceptable estimating errors. We also apply the MF-X-WL method to pairs of series from financial markets (returns and volatilities) and online worlds (online numbers of different genders and different societies) and determine intriguing joint multifractal behavior.

  18. Experimental and theoretical investigations on temperature distribution at the joint interface for copper joints using ultrasonic welding

    Directory of Open Access Journals (Sweden)

    Elangovan Sooriya


    Full Text Available Ultrasonic welding is a solid-state joining process that produces joints by the application of high frequency vibratory energy in the work pieces held together under pressure without melting. Copper and its alloys are extensively used in electrical and electronic industry because of its excellent electrical and thermal properties. This paper mainly focused on temperature distribution and the influence of process parameters at the joint interface while joining copper sheets using ultrasonic welding process. Experiments are carried out using Cu sheets (0.2 mm and 0.3 mm thickness and the interface temperature is measured using Data Acquisition (DAQ System (thermocouple and thermal imager. Numerical and finite element based model for temperature distribution at the interface are developed and solved the same using Finite Difference Method (FDM and Finite Element Analysis (FEA. The results obtained from FDM and FEA model shows similar trend with experimental results and are found to be in good agreement.

  19. High Temperature Joining and Characterization of Joint Properties in Silicon Carbide-Based Composite Materials (United States)

    Halbig, Michael C.; Singh, Mrityunjay


    Advanced silicon carbide-based ceramics and composites are being developed for a wide variety of high temperature extreme environment applications. Robust high temperature joining and integration technologies are enabling for the fabrication and manufacturing of large and complex shaped components. The development of a new joining approach called SET (Single-step Elevated Temperature) joining will be described along with the overview of previously developed joining approaches including high temperature brazing, ARCJoinT (Affordable, Robust Ceramic Joining Technology), diffusion bonding, and REABOND (Refractory Eutectic Assisted Bonding). Unlike other approaches, SET joining does not have any lower temperature phases and will therefore have a use temperature above 1315C. Optimization of the composition for full conversion to silicon carbide will be discussed. The goal is to find a composition with no remaining carbon or free silicon. Green tape interlayers were developed for joining. Microstructural analysis and preliminary mechanical tests of the joints will be presented.

  20. Density, temperature and composition of the North American lithosphere: new insights from a joint analysis of seismic, gravity and mineral physics data: 2. Thermal and compositional model of the upper mantle.

    NARCIS (Netherlands)

    Tesauro, Magdala; Kaban, Mikhail; Mooney, Walter; Cloetingh, Sierd


    Temperature and compositional variations of the North American (NA) lithospheric mantle are estimated using a new inversion technique introduced in Part I, which allows us to jointly interpret seismic tomography and gravity data, taking into account depletion of the lithospheric mantle beneath the


    Directory of Open Access Journals (Sweden)



    Full Text Available The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points corresponding to each end of the two conveyor belts on the both sides of the band, namely the active and inactive side.

  2. Reliability Analysis of Adhesive Bonded Scarf Joints

    DEFF Research Database (Denmark)

    Kimiaeifar, Amin; Toft, Henrik Stensgaard; Lund, Erik


    A probabilistic model for the reliability analysis of adhesive bonded scarfed lap joints subjected to static loading is developed. It is representative for the main laminate in a wind turbine blade subjected to flapwise bending. The structural analysis is based on a three dimensional (3D) finite...... the FEA model, and a sensitivity analysis on the influence of various geometrical parameters and material properties on the maximum stress is conducted. Because the yield behavior of many polymeric structural adhesives is dependent on both deviatoric and hydrostatic stress components, different ratios...... of the compressive to tensile adhesive yield stresses in the failure criterion are considered. It is shown that the chosen failure criterion, the scarf angle and the load are significant for the assessment of the probability of failure....

  3. GISS Surface Temperature Analysis (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GISTEMP dataset is a global 2x2 gridded temperature anomaly dataset. Temperature data is updated around the middle of every month using current data files from...

  4. Reliability Analysis of Tubular Joints in Offshore Structures

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard


    Reliability analysis of single tubular joints and offshore platforms with tubular joints is" presented. The failure modes considered are yielding, punching, buckling and fatigue failure. Element reliability as well as systems reliability approaches are used and illustrated by several examples....... Finally, optimal design of tubular.joints with reliability constraints is discussed and illustrated by an example....

  5. Design and Performance Analysis of a new Rotary Hydraulic Joint (United States)

    Feng, Yong; Yang, Junhong; Shang, Jianzhong; Wang, Zhuo; Fang, Delei


    To improve the driving torque of the robots joint, a wobble plate hydraulic joint is proposed, and the structure and working principle are described. Then mathematical models of kinematics and dynamics was established. On the basis of this, dynamic simulation and characteristic analysis are carried out. Results show that the motion curve of the joint is continuous and the impact is small. Moreover the output torque of the joint characterized by simple structure and easy processing is large and can be rotated continuously.

  6. Joint variability of global runoff and global sea surface temperatures (United States)

    McCabe, G.J.; Wolock, D.M.


    Global land surface runoff and sea surface temperatures (SST) are analyzed to identify the primary modes of variability of these hydroclimatic data for the period 1905-2002. A monthly water-balance model first is used with global monthly temperature and precipitation data to compute time series of annual gridded runoff for the analysis period. The annual runoff time series data are combined with gridded annual sea surface temperature data, and the combined dataset is subjected to a principal components analysis (PCA) to identify the primary modes of variability. The first three components from the PCA explain 29% of the total variability in the combined runoff/SST dataset. The first component explains 15% of the total variance and primarily represents long-term trends in the data. The long-term trends in SSTs are evident as warming in all of the oceans. The associated long-term trends in runoff suggest increasing flows for parts of North America, South America, Eurasia, and Australia; decreasing runoff is most notable in western Africa. The second principal component explains 9% of the total variance and reflects variability of the El Ni??o-Southern Oscillation (ENSO) and its associated influence on global annual runoff patterns. The third component explains 5% of the total variance and indicates a response of global annual runoff to variability in North Aflantic SSTs. The association between runoff and North Atlantic SSTs may explain an apparent steplike change in runoff that occurred around 1970 for a number of continental regions.

  7. Development of remountable joints and heat removable techniques for high-temperature superconducting magnets (United States)

    Hashizume, H.; Ito, S.; Yanagi, N.; Tamura, H.; Sagara, A.


    Segment fabrication is now a candidate for the design of superconducting helical magnets in the helical fusion reactor FFHR-d1, which adopts the joint winding of high-temperature superconducting (HTS) helical coils as a primary option and the ‘remountable’ HTS helical coil as an advanced option. This paper reports on recent progress in two key technologies: the mechanical joints (remountable joints) of the HTS conductors and the metal porous media inserted into the cooling channel for segment fabrication. Through our research activities it has been revealed that heat treatment during fabrication of the joint can reduce joint resistance and its dispersion, which can shorten the fabrication process and be applied to bent conductor joints. Also, heat transfer correlations of the cooling channel were established to evaluate heat transfer performance with various cryogenic coolants based on the correlations to analyze the thermal stability of the joint.

  8. Surface Temperature Data Analysis (United States)

    Hansen, James; Ruedy, Reto


    Small global mean temperature changes may have significant to disastrous consequences for the Earth's climate if they persist for an extended period. Obtaining global means from local weather reports is hampered by the uneven spatial distribution of the reliably reporting weather stations. Methods had to be developed that minimize as far as possible the impact of that situation. This software is a method of combining temperature data of individual stations to obtain a global mean trend, overcoming/estimating the uncertainty introduced by the spatial and temporal gaps in the available data. Useful estimates were obtained by the introduction of a special grid, subdividing the Earth's surface into 8,000 equal-area boxes, using the existing data to create virtual stations at the center of each of these boxes, and combining temperature anomalies (after assessing the radius of high correlation) rather than temperatures.

  9. Double-composite rectangular truss bridge and its joint analysis

    Directory of Open Access Journals (Sweden)

    Yongjian Liu


    Full Text Available This paper describes a novel composite tubular truss bridge with concrete slab and concrete-filled rectangular chords. With concrete slab plus truss system and joints reinforced with concrete and Perfobond Leiste rib, double composite truss bridge proved to be a fairly suitable solution in negative moment area. Perfobond Leiste shear connector (PBL is widely implemented in the composite structure for its outstanding fatigue resistance. In this pilot bridge, Perfobond Leister ribs (PBR were installed in the truss girder's joints, which played double roles as shear connector and stiffener. An erection method and overall bridge structural analysis were then presented. Typical joints in the pilot bridge were selected to analyze the effect of PBR. Investigation of the effect of PBR in concrete-filled tubular joints was elaborated. Comparison has revealed that concrete-filled tubular joints with PBR have much higher constraint capability than joints without PBR. For rectangular tubular truss, the punching shear force of the concrete filled joint with PBR is approximately 43% larger than that of the joint without PBR. Fatigue performance of the joint installed with PBR was improved, which was found through analysis of the stress concentration factor of joint. The PBR installed in the joints mitigated the stress concentration factor in the chord face. Therefore, the advantages of this new type of bridge are demonstrated, including the convenience of construction using rectangular truss, innovative concept of structural design and better global and local performances.

  10. Advances in the analysis and design of adhesive-bonded joints in composite aerospace structures (United States)

    Hart-Smith, L. J.


    Several aspects of adhesive-bonded joint analysis and design are presented from the reference of size of structure or load intensity. This integrates the individual characterizations of double-lap, single-lap, stepped-lap, tapered-lap and scarf joints. The paper includes an overview of bonded joint selection from the standpoints of design, fabrication, and processing, each bearing in mind the influence of such considerations on the strength of the joint. A case study is presented of the optimization of a specific relatively thick titanium-to-graphite epoxy stepped-lap joint, using the digital computer analysis program A4EG. The factors accounted for are adhesive plasticity, adherend stiffness imbalance, adherend thermal mismatch, and change of material properties within the range of temperature environment and with load direction. The strength increases obtainable by refining the initial design are demonstrated.

  11. Effects of radiofrequency probe application on irrigation fluid temperature in the wrist joint. (United States)

    Sotereanos, Dean G; Darlis, Nickolaos A; Kokkalis, Zinon T; Zanaros, George; Altman, Gregory T; Miller, Mark Carl


    Radiofrequency (RF) probes used in wrist arthroscopy may raise joint fluid temperature, increasing the risk of capsular and ligamentous damage. The purposes of the current study were to measure joint fluid temperature during wrist arthroscopy with the use of RF probes, and to determine whether using an outlet portal will reduce the maximum temperature. We performed wrist arthroscopy on 8 cadaveric arms. Ablation and coagulation cycles using RF probe were performed at documented locations within the joint. This was done for 60-second intervals on both the radial and ulnar side of the wrist, to mimic clinical practice. We used 4 fiberoptic phosphorescent probes to measure temperature (radial, ulnar, inflow-tube, and outflow-tube probes) and measured joint fluid temperature with and without outflow. There was a significant difference between wrists with and without outflow when examining maximum ablation temperatures (p wrist arthroscopy, the use of an outlet portal reduces the joint fluid temperature. Without an outlet portal, maximum temperatures can exceed desirable levels when using ablation; such temperatures have the potential to damage adjacent tissues. It is useful to maintain adequate outflow when using the radiofrequency probes during wrist arthroscopy.

  12. Double symbolic joint entropy in nonlinear dynamic complexity analysis (United States)

    Yao, Wenpo; Wang, Jun


    Symbolizations, the base of symbolic dynamic analysis, are classified as global static and local dynamic approaches which are combined by joint entropy in our works for nonlinear dynamic complexity analysis. Two global static methods, symbolic transformations of Wessel N. symbolic entropy and base-scale entropy, and two local ones, namely symbolizations of permutation and differential entropy, constitute four double symbolic joint entropies that have accurate complexity detections in chaotic models, logistic and Henon map series. In nonlinear dynamical analysis of different kinds of heart rate variability, heartbeats of healthy young have higher complexity than those of the healthy elderly, and congestive heart failure (CHF) patients are lowest in heartbeats' joint entropy values. Each individual symbolic entropy is improved by double symbolic joint entropy among which the combination of base-scale and differential symbolizations have best complexity analysis. Test results prove that double symbolic joint entropy is feasible in nonlinear dynamic complexity analysis.

  13. Progressive Damage Analysis of Bonded Composite Joints (United States)

    Leone, Frank A., Jr.; Girolamo, Donato; Davila, Carlos G.


    The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented durable redundant joint. Both designs involve honeycomb sandwich structures with carbon/epoxy facesheets joined using adhesively bonded doublers.Progressive damage modeling allows for the prediction of the initiation and evolution of damage within a structure. For structures that include multiple material systems, such as the joint designs under consideration, the number of potential failure mechanisms that must be accounted for drastically increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, intraply matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The bonded joints were modeled using highly parametric, explicitly solved finite element models, with damage modeling implemented via custom user-written subroutines. Each ply was discretely meshed using three-dimensional solid elements. Layers of cohesive elements were included between each ply to account for the possibility of delaminations and were used to model the adhesive layers forming the joint. Good correlation with experimental results was achieved both in terms of load-displacement history and the predicted failure mechanism(s).

  14. Design, Static Analysis And Fabrication Of Composite Joints (United States)

    Mathiselvan, G.; Gobinath, R.; Yuvaraja, S.; Raja, T.


    The Bonded joints will be having one of the important issues in the composite technology is the repairing of aging in aircraft applications. In these applications and also for joining various composite material parts together, the composite materials fastened together either using adhesives or mechanical fasteners. In this paper, we have carried out design, static analysis of 3-D models and fabrication of the composite joints (bonded, riveted and hybrid). The 3-D model of the composite structure will be fabricated by using the materials such as epoxy resin, glass fibre material and aluminium rivet for preparing the joints. The static analysis was carried out with different joint by using ANSYS software. After fabrication, parametric study was also conducted to compare the performance of the hybrid joint with varying adherent width, adhesive thickness and overlap length. Different joint and its materials tensile test result have compared.

  15. Analysis on High Temperature Aging Property of Self-brazing Aluminum Honeycomb Core at Middle Temperature

    Directory of Open Access Journals (Sweden)

    ZHAO Huan


    Full Text Available Tension-shear test was carried out on middle temperature self-brazing aluminum honeycomb cores after high temperature aging by micro mechanical test system, and the microstructure and component of the joints were observed and analyzed using scanning electron microscopy and energy dispersive spectroscopy to study the relationship between brazing seam microstructure, component and high temperature aging properties. Results show that the tensile-shear strength of aluminum honeycomb core joints brazed by 1060 aluminum foil and aluminum composite brazing plate after high temperature aging(200℃/12h, 200℃/24h, 200℃/36h is similar to that of as-welded joints, and the weak part of the joint is the base metal which is near the brazing joint. The observation and analysis of the aluminum honeycomb core microstructure and component show that the component of Zn, Sn at brazing seam is not much affected and no compound phase formed after high temperature aging; therefore, the main reason for good high temperature aging performance of self-brazing aluminum honeycomb core is that no obvious change of brazing seam microstructure and component occurs.

  16. Fracture failure analysis of Fiber Reinforced Composites T-joints (United States)

    Su, Wei; Kong, De-zhi; Liu, Ren-huai; Huang, Shi-qing


    This paper discusses staple FRP T-joints on the project based on the classical beam theory of Euler-Bernoulli and a theoretical model of energy release rate is set up to discuss fracture propagation of composite T-joints. The paper is further analysis on fracture failure affected by composite pane depth and joints chamfer dimension parameters and so on. The conclusion benefit for extensive use of projects is also summarized.

  17. Finite element analysis of tubular joints in offshore structures ...

    African Journals Online (AJOL)

    This research work was involved in the finite element tool to determine the ultimate strength of initially uncorked joints, which fail by development of tearing fracture at the weld toe. The local approach methodology in contrast to classical fracture mechanics was used. Finite element analysis was done of T-joint plate ...

  18. Gait analysis of adults with generalised joint hypermobility

    DEFF Research Database (Denmark)

    Simonsen, Erik B; Tegner, Heidi; Alkjær, Tine


    BACKGROUND: The majority of adults with Generalised Joint Hypermobility experience symptoms such as pain and joint instability, which is likely to influence their gait pattern. Accordingly, the purpose of the present project was to perform a biomechanical gait analysis on a group of patients...

  19. Tensile properties and fracturing behavior of weld joints in the CLAM at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Yucheng [School of Material Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Xiao, Chengwen, E-mail: [School of Material Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); Wang, Xu; Yue, Jiajia; Zhu, Qiang [School of Material Science and Engineering, Jiangsu University, Zhenjiang 212013 (China)


    Highlights: • We use the stress triaxiality theory to explain the plastic deformation and facture behavior of the joints during the short term tensile tests at high temperature. • The tensile strength of CLAM welded joint at high temperature is lower compared with that at room temperature. • We explained the formation of crack and the reason of fracture. - Abstract: The tensile properties and fracturing behavior of weld joints in the Chinese low activation martensitic steel (CLAM) at high temperatures were studied. The result revealed that the cracks of weld joints in the base metal would appear in the heat-affected zone, after post-weld heat treatment for the high-temperature tensile test. The microstructure in the fractured frontier had different deformation and directions, and the fractured surface had different angles, a result associating with the normal faulting and shear fracturing. The tri-axial theory of stress can well explain the deformation and fracturing behavior of weld joints in the high-temperature tensile.

  20. Fractal Analysis of Rock Joint Profiles (United States)

    Audy, Ondřej; Ficker, Tomáš


    Surface reliefs of rock joints are analyzed in geotechnics when shear strength of rocky slopes is estimated. The rock joint profiles actually are self-affine fractal curves and computations of their fractal dimensions require special methods. Many papers devoted to the fractal properties of these profiles were published in the past but only a few of those papers employed a convenient computational method that would have guaranteed a sound value of that dimension. As a consequence, anomalously low dimensions were presented. This contribution deals with two computational modifications that lead to sound fractal dimensions of the self-affine rock joint profiles. These are the modified box-counting method and the modified yard-stick method sometimes called the compass method. Both these methods are frequently applied to self-similar fractal curves but the self-affine profile curves due to their self-affine nature require modified computational procedures implemented in computer programs.

  1. Development of metal-ceramic brazed joints for high temperature applications: example of SiC-Inconel joints

    Energy Technology Data Exchange (ETDEWEB)

    Baffie, T. [CEA/LITEN-DTH, Lab. of Hydrogen Technologies, Grenoble (France); Ziombra, A. [RWTH Aachen (Germany); Schicktanz, R. [BURGMANN Industries, Wolfratshausen (Germany)


    For many applications, sintered silicon carbide SiC, used in high temperature and corrosive environments, has to be brazed to a metal. Nowadays, there is still no tight solution for SiC/metal joints working higher than 400 C; this is mainly explained by chemical (high reactivity) and thermomechanical (high thermal expansion mismatch) incompatibilities between ceramics and metals. These two key points were addressed through the use of a low-active filler metal and interlayer materials. Numerical simulation was employed to optimise the design of the joints and the shape of the parts and thus, reduce stresses on SiC. SiC/metal brazed prototypes of industrial parts were fabricated and tested up to 400 C and failure. (orig.)

  2. Experimental investigation on the failure of T-joints at elevated temperature under unaxial loading (United States)

    Bahri, N. F.; Afendi, M.; Razlan, Z. M.; Nor, A.; Baharuddin, S. A.


    In this study, the mechanical properties and maximum failure load of a bulk and T-joints subjected to tensile loading were investigated experimentally. A bulk and the T-joint specimens were fabricated and tested in order to investigate the effects of temperature conditions on the failure of the joints. The adherent and adhesive used for T-joint are 304 L stainless steel and Hysol E 214 HP with the adhesive thickness of 1.0 mm. The tensile test of the bulk specimen and adhesively T-joint were conducted by using a universal testing machine (UTM) at room temperature (RT), 55 °C, 75 °C, 100 °C and 120 °C, respectively. It was found that as the temperature increases, the failure force strength decreases for bulk and T-joint specimen. Data obtained from the tests at 120 °C showed the failure force of the bulk adhesive decreased by approximately 44 % compared to the specimen tested at RT. Next, the bulk of Hysol failure force result was compared with Araldite at RT and 100 °C. Araldite data was taken from the previous study [1]. It has also been found that the bulk for Hysol has higher failure force compared to Araldite at RT and 100 °C.

  3. Distributed Aperture Coherence-synthetic Radar Joint Antenna Gain Analysis

    Directory of Open Access Journals (Sweden)

    Zhou Baoliang


    Full Text Available By the synthesis of multi-radar electromagnetic wave space energy, Distributed Aperture Coherencesynthetic Radar (DACR achieves long-range power detection via multi-radar airspace expansion to realize high-precision target angle measurement. DACR has the advantages of strong survival ability, a high cost- effectiveness ratio, high angular accuracy, strong expandability, and easy realization. In this article, we analyze the joint antenna gain of a non-directional multi-point source and, given the theoretical derivation and simulation analysis, we establish a distributed-array-antenna geometric model, analyze the joint antenna pattern and gain, respectively, and determine that the joint antenna gain is approximately equal to the unit radar number and the unit radar gain product. Lastly, we perform a joint antenna gain simulation using HFSS software to further verify the joint antenna gain results.

  4. Majorana Demonstrator Bolted Joint Mechanical and Thermal Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Navarrete, Estanislao; Reid, Douglas J.; Fast, James E.


    The MAJORANA DEMONSTRATOR is designed to probe for neutrinoless double-beta decay, an extremely rare process with a half-life in the order of 1026 years. The experiment uses an ultra-low background, high-purity germanium detector array. The germanium crystals are both the source and the detector in this experiment. Operating these crystals as ionizing radiation detectors requires having them under cryogenic conditions (below 90 K). A liquid nitrogen thermosyphon is used to extract the heat from the detectors. The detector channels are arranged in strings and thermally coupled to the thermosyphon through a cold plate. The cold plate is joined to the thermosyphon by a bolted joint. This circular plate is housed inside the cryostat can. This document provides a detailed study of the bolted joint that connects the cold plate and the thermosyphon. An analysis of the mechanical and thermal properties of this bolted joint is presented. The force applied to the joint is derived from the torque applied to each one of the six bolts that form the joint. The thermal conductivity of the joint is measured as a function of applied force. The required heat conductivity for a successful experiment is the combination of the thermal conductivity of the detector string and this joint. The thermal behavior of the joint is experimentally implemented and analyzed in this study.

  5. Effects of bonding temperature on microstructure, fracture behavior and joint strength of Ag nanoporous bonding for high temperature die attach

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min-Su, E-mail: [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Nishikawa, Hiroshi [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)


    Ag nanoparticle sintering has received much attention as an alternative joining method to lead-based soldering for high temperature electronic applications. However, there are still certain issues with this method, such as difficulties of in controlling the joining layer thickness and the occurrence of unexpected voids resulting from solvent evaporation. In this study, the effect of bonding temperature (200–400 °C) and environment (air and N{sub 2}) on the joint strength of Ag nanoporous bonding (NPB) on electroless nickel/immersion gold finished Cu disks was investigated. A nanoporous Ag sheet fabricated using dealloying method from an Al–Ag precursor was adopted as the insert material. The NPB was conducted at various temperatures (200–400 °C) for 30 min at a pressure of 20 MPa in both air and N{sub 2} environments. The joint strength of NPB was closely related with the microstructure of the Ag layer and the fracture mode of the joint, and increased with increasing bonding temperature through the formation of strong interface and a coarsened Ag layer. The effect of the bonding environment was not significant, except in the case of bonding temperature of 400 °C.

  6. The effect of ambient temperature on infrared thermographic images of joints in the distal forelimbs of healthy racehorses. (United States)

    Soroko, Maria; Howell, Kevin; Dudek, Krzysztof


    The aim of the study was to describe the dependence on ambient temperature of distal joint temperature at the forelimbs of racehorses. The study also investigated the influence of differing ambient temperatures on the temperature difference between joints: this was measured ipsilaterally (i.e. between the carpal and fetlock joints along each forelimb) and contralaterally (i.e. between the same joints of the left and right forelimbs). Sixty-four healthy racehorses were monitored over 10 months. At each session, three thermographic images were taken of the dorsal, lateral and medial aspects of the distal forelimbs. Temperature measurements were made from regions of interest (ROIs) covering the carpal and fetlock joints. There was a strong correlation between ambient temperature and absolute joint temperature at all ROIs. The study also observed a moderate correlation between ambient temperature and the ipsilateral temperature differences between joints when measured from the medial and lateral aspects. No significant correlation was noted when measured dorsally. The mean contralateral temperature differences between joints were all close to 0°C. The data support previous reports that the temperature distribution between the forelimbs of the healthy equine is generally symmetric, although some horses differ markedly from the average findings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Highly Conductive Cu-Cu Joint Formation by Low-Temperature Sintering of Formic Acid-Treated Cu Nanoparticles. (United States)

    Liu, Jingdong; Chen, Hongtao; Ji, Hongjun; Li, Mingyu


    Highly conductive Cu-Cu interconnections of SiC die with Ti/Ni/Cu metallization and direct bonded copper substrate for high-power semiconductor devices are achieved by the low-temperature sintering of Cu nanoparticles with a formic acid treatment. The Cu-Cu joints formed via a long-range sintering process exhibited good electrical conductivity and high strength. When sintered at 260 °C, the Cu nanoparticle layer exhibited a low resistivity of 5.65 μΩ·cm and the joints displayed a high shear strength of 43.4 MPa. When sintered at 320 °C, the resistivity decreased to 3.16 μΩ·cm and the shear strength increased to 51.7 MPa. The microstructure analysis demonstrated that the formation of Cu-Cu joints was realized by metallurgical bonding at the contact interface between the Cu pad and the sintered Cu nanoparticle layer, and the densely sintered layer was composed of polycrystals with a size of hundreds of nanometers. In addition, high-density twins were found in the interior of the sintered layer, which contributed to the improvement of the performance of the Cu-Cu joints. This bonding technology is suitable for high-power devices operating under high temperatures.

  8. Radiographic analysis of temporomandibular joint arthrosis

    Energy Technology Data Exchange (ETDEWEB)

    You, Dong Soo [Department of Oral Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)


    The author analysed the bone changes, the positional relationships between condylar head and articular fossa, and the interrelationship between the bone changes and the abnormal position of condylar head, from 1,036 radiographs of 259 patients with temporomandibular joint arthrosis, which were obtained by the oblique-lateral transcranial projection and orthopantomograms. The results were as follows: 1. Among the radiographic bone changes of the temporomandibular joint arthrosis, deformity was 36..90% (217 cases), sclerosis 34.18% (201 cases), erosive change 25.58% (152 cases) and marginal proliferation 3.06% (18 cases) respectively. 2. In the positional changes between condylar head and articular fossa, the downward positioning of condylar head in centric occlusion was most frequent (36.90%), of which frequency was significantly higher than forward positioning (11.22%) and backward positioning (4.76%) in same condition. Also, radiographs showed that the enlargement of articular space showed higher frequency than its narrowing. In the opening position of mouth, the restrict ed movement of condylar head within articular fossa was most frequent (35.03%). The forward positioning and the downward positioning was 15.65% and 9.52% respectively. Also, radiographs revealed that the incomplete movement or no positional change of condylar head was most frequent. 3. In the interrelationship between bone changes and abnormal position of condylar head, deformity was 42.79% in the cases of downward positioning of condylar head in centric occlusion and 37.50% in those of normal positioning of condylar head in same condition. This revealed that deformity was most frequent bone change in above condylar positionings. However, erosive change was 34.62% in the cases of downward positioning of condylar head in centric occlusion and 33 .33% in those of forward positioning. In opening position of condylar head, and deformity in the cases of norma l positioning, forward positioning and

  9. Influence of temperature on strength and failure mechanisms of resistance welded thermoplastic composites joints

    NARCIS (Netherlands)

    Koutras, N.; Fernandez Villegas, I.; Benedictus, R.


    In this work, the effect of temperature exposure on the strength of resistance welded joints is analysed. Glass fibre polyphenylene sulphide (GF/PPS) laminates were joined using the resistance welding technique and a stainless steel metal mesh as the heating element. Single lap shear tests at

  10. Finite element analysis of human joints

    Energy Technology Data Exchange (ETDEWEB)

    Bossart, P.L.; Hollerbach, K.


    Our work focuses on the development of finite element models (FEMs) that describe the biomechanics of human joints. Finite element modeling is becoming a standard tool in industrial applications. In highly complex problems such as those found in biomechanics research, however, the full potential of FEMs is just beginning to be explored, due to the absence of precise, high resolution medical data and the difficulties encountered in converting these enormous datasets into a form that is usable in FEMs. With increasing computing speed and memory available, it is now feasible to address these challenges. We address the first by acquiring data with a high resolution C-ray CT scanner and the latter by developing semi-automated method for generating the volumetric meshes used in the FEM. Issues related to tomographic reconstruction, volume segmentation, the use of extracted surfaces to generate volumetric hexahedral meshes, and applications of the FEM are described.

  11. Temperature analysis in CFRP drilling (United States)

    Matsumura, Takashi; Tamura, Shoichi


    The cutting temperature in drilling of carbon fiber reinforced plastics (CFRPs) is simulated numerically in finite difference analysis. The cutting force is predicted to estimate heat generation on the shear plane and the rake face by an energy approach. In the force model, three dimensional chip flow is interpreted as a piling up of the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities, in which the chip flow direction is determined to minimize the cutting energy. Then, the cutting force is predicted in the determined chip flow model. The cutting temperature distribution is simulated with the thermal conductions, the thermal convections and the heat generations in the discrete elements of the tool, the chip and the workpiece. The heat generations on the shear plane and the rake face are given by stress distributions based on the cutting force predicted. The cutting temperature is analyzed on assumption that all mechanical works contribute the heat generation. The temperature of CFRP is compared with that of carbon steel in the numerical simulation. The maximum temperature of CFRP is much lower than carbon steel. The position at the maximum temperature is near the tool tip due to a low thermal conductivity of CFRP.

  12. Fracture analysis of adhesive joints in wind turbine blades

    DEFF Research Database (Denmark)

    Eder, Martin Alexander; Bitsche, Robert


    Modern wind turbine rotor blades are usually made from fibre-reinforced composite subcomponents. In the final assembly stage, these subcomponents are bonded together by several adhesive joints. One important adhesive joint is situated at the trailing edge, which refers to the downstream edge where...... information is scarce. This paper is concerned with the fracture analysis of adhesive joints in general, with a particular focus on trailing edges. For that, the energy release rates in prescribed cracks present in the bond line of a generic trailing edge joint are investigated. In connection...... with this examination, the paper elucidates the influence of geometrical non-linearity in form of local buckling on both the increase of the energy release rate and the change of mode mixity. First, experimental results on adhesively bonded small-scale subcomponents are presented. Thereafter, a practical approach...

  13. Spatiotemporal and joint probability behavior of temperature extremes over the Himalayan region under changing climate (United States)

    Goswami, Uttam P.; Bhargav, K.; Hazra, B.; Goyal, Manish Kumar


    In this study, temperature extremes are analyzed for observed (1979-2005) and projected scenarios using three global climate models (GCMs) and their Representative Concentration Pathways (RCPs) based on Coupled Model Intercomparison Project Phase 5 (CMIP5) datasets, to investigate the spatio-temporal variations and possible changes in joint probability behavior of temperature extremes over North Sikkim Himalaya, India. Statistical downscaling model (SDSM) and copulas are applied to downscale the GCM outputs and to construct joint probability distribution of extremes, respectively. A set of ten climate extreme indices are selected to understand the inter-annual variability. Joint return period of extreme indices was calculated using six temperature extreme indices (based on days). Linear trends were estimated using Mann Kendall test with statistical significance and indicated widespread significant changes in temperature extremes. The significant changes in temperature extremes such as the temperature of warmest night and day have increased by 1.41 and 1.83 °C, and the temperature of coldest night and day has decreased by 3.61 and 4.83 °C, respectively, during 2006-2100 with the baseline period of 1979-2005. The spatial distribution of 5-year return periods and 10-year return periods is almost similar during 1979-2005. There is less co-occurrence of warm nights and days, but higher chance to co-occurrence of cool and warm nights in the same year during 2021-2100. The change in joint return periods under the RCP8.5 shows frequent co-occurrence of cool days and nights, ice and frost days, and cool and frost days than RCP2.6 and RCP4.5. This study implies that the warm days, cool days, warmer nights, and cool nights are decreased with increased warming intensity, which shows the overall warming trend over the North Sikkim Himalaya, India.

  14. Progressive Failure Analysis on the Single Lap Bonded Joints

    Directory of Open Access Journals (Sweden)

    Kadir TURAN


    Full Text Available In this study, the failure analysis on the single lap bonded joint, which is used for joined two composite plates each other with adhesive, is investigated experimentally and numerically. In the joint, the epoxy resin is used for adhesive and the four layered carbon fiber reinforced epoxy matrix resin composite plates are used for adherent. Numerical study is performed in the ANSYS software which is used finite element method for solution. For obtained numerical failure loads, the progressive failure analysis is used with material property degradation rules. In the failure analysis the Hashin Failure Criterion is used for composite plates and the Maximum Principal Stress failure criterion is used for adhesive. The effects of the adhesive thickness overlap lengths and plate weight on the joint strength is investigated with numerically. As a result it is seen that the failure loads is affected the bond face area. The results are presented with graphs and tables.


    Directory of Open Access Journals (Sweden)

    Thomas GEREKE


    Full Text Available Engineered wood products such as glulam or cross-laminated timber are widely established in the construction industry. Their structural behaviour and reliability clearly bases on the adhesive bonding. In order to understand and improve the performance of glued wood members a finite element modelling of standard single lap shear samples was carried out. A three-dimensional model of a longitudinal tensile-shear specimen with quasi-centric load application was developed. The main influences of wood and adhesive parameters on structural performance were identified. Therefore, variations of the elasticity, the annual ring angle, fibre angle, and the interface zone and their effect on the occurring stresses in the adhesive bond line were investigated numerically. The adhesive bond line is most significantly sensitive to the Young´s modulus of the adhesive itself. A variation of the fibre angle of the glued members in the standard test is an essential criterion and to be considered when preparing lap shear specimens. A model with representation of early- and latewood gives a more detailed insight into wooden adhesive joints.

  16. Experimental and failure analysis of the prosthetic finger joint implants (United States)

    Naidu, Sanjiv H.

    Small joint replacement arthroplasty of the hand is a well accepted surgical procedure to restore function and cosmesis in an individual with a crippled hand. Silicone elastomers have been used as prosthetic material in various small hand joints for well over three decades. Although the clinical science aspects of silicone elastomer failure are well known, the physical science aspects of prosthetic failure are scant and vague. In the following thesis, using both an animal model, and actual retrieved specimens which have failed in human service, experimental and failure analysis of silicone finger joints are presented. Fractured surfaces of retrieved silicone trapezial implants, and silicone finger joint implants were studied with both FESEM and SEM; the mode of failure for silicone trapezium is by wear polishing, whereas the finger joint implants failed either by fatigue fracture or tearing of the elastomer, or a combination of both. Thermal analysis revealed that the retrieved elastomer implants maintained its viscoelastic properties throughout the service period. In order to provide for a more functional and physiologic arthroplasty a novel finger joint (Rolamite prosthesis) is proposed using more recently developed thermoplastic polymers. The following thesis also addresses the outcome of the experimental studies of the Rolamite prosthesis in a rabbit animal model, in addition to the failure analysis of the thermoplastic polymers while in service in an in vivo synovial environment. Results of retrieved Rolamite specimens suggest that the use for thermoplastic elastomers such as block copolymer based elastomers in a synovial environment such as a mammalian joint may very well be limited.

  17. Joint aspiration and injection and synovial fluid analysis. (United States)

    Courtney, Philip; Doherty, Michael


    Joint aspiration/injection and synovial fluid (SF) analysis are both invaluable procedures for the diagnosis and treatment of joint disease. This chapter addresses (1) the indications, technical principles, expected benefits and risks of aspiration and injection of intra-articular corticosteroid and (2) practical aspects relating to SF analysis, especially in relation to crystal identification. Intra-articular injection of long-acting insoluble corticosteroids is a well-established procedure that produces rapid pain relief and resolution of inflammation in most injected joints. The knee is the most common site to require aspiration although any non-axial joint is accessible for obtaining SF. The technique involves only knowledge of basic anatomy and should not be unduly painful for the patient. Provided sterile equipment and a sensible, aseptic approach are used, it is very safe. Analysis of aspirated SF is helpful in the differential diagnosis of arthritis and is the definitive method for diagnosis of septic arthritis and crystal arthritis. The gross appearance of SF can provide useful diagnostic information in terms of the degree of joint inflammation and presence of haemarthrosis. Microbiological studies of SF are the key to the confirmation of infectious conditions. Increasing joint inflammation associates with increased SF volume, reduced viscosity, increasing turbidity and cell count and increasing ratio of polymorphonuclear:mononuclear cells, but such changes are non-specific and must be interpreted in the clinical setting. However, detection of SF monosodium urate and calcium pyrophosphate dihydrate crystals, even from un-inflamed joints during intercritical periods, allows a precise diagnosis of gout and calcium pyrophosphate crystal-related arthritis. Copyright © 2013. Published by Elsevier Ltd.

  18. Computational Modelling and Movement Analysis of Hip Joint with Muscles (United States)

    Siswanto, W. A.; Yoon, C. C.; Salleh, S. Md.; Ngali, M. Z.; Yusup, Eliza M.


    In this study, the model of hip joint and the main muscles are modelled by finite elements. The parts included in the model are hip joint, hemi pelvis, gluteus maximus, quadratus femoris and gamellus inferior. The materials that used in these model are isotropic elastic, Mooney Rivlin and Neo-hookean. The hip resultant force of the normal gait and stair climbing are applied on the model of hip joint. The responses of displacement, stress and strain of the muscles are then recorded. FEBio non-linear solver for biomechanics is employed to conduct the simulation of the model of hip joint with muscles. The contact interfaces that used in this model are sliding contact and tied contact. From the analysis results, the gluteus maximus has the maximum displacement, stress and strain in the stair climbing. Quadratus femoris and gamellus inferior has the maximum displacement and strain in the normal gait however the maximum stress in the stair climbing. Besides that, the computational model of hip joint with muscles is produced for research and investigation platform. The model can be used as a visualization platform of hip joint.

  19. Kinematic analysis of the knee joint by cine MRI

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, Mamoru; Akisada, Masayoshi; Anno, Izumi; Matsumoto, Kunihiko; Kuno, Shin-ya; Miyakawa, Shunpei (Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine); Inouye, Tamon; Kose, Katsumi


    In order to obtain the MR imaging of a moving knee joint, we developed a drive system of the knee. A reciprocating reversible motor with a rope and pulleys drove a knee brace with the knee bending and extending every two seconds. Using photo sensor probe for gating cine acquisition, we got 16-time frames/cycle MR images. Such as articular cartilage, ligaments and synovial fluid, the fine components of a moving knee joint were clearly seen. In a dynamic display, these cine images demonstrated 'actual' movement of the knee joint. Moving joint fluid and defect of anterior cruciate ligament were demonstrated in the case of knee injury. These findings were not seen on static images. Cine MR imaging was also helpful for evaluating the chronic joint disease and ligament reconstruction. Through the use of the present drive system and cine acquisition, dynamic MR imaging of a moving knee joint is clearly demonstrated and it may provide useful information in the kinematic analysis of the normal and pathologic knee. (author).

  20. Joint motion quality in vibroacoustic signal analysis for patients with patellofemoral joint disorders. (United States)

    Bączkowicz, Dawid; Majorczyk, Edyta


    Chondromalacia, lateral patellar compression syndrome and osteoarthritis are common patellofemoral joint disorders leading to functional and/or structural disturbances in articular surfaces. The objective of the study was to evaluate their impact on joint motion quality via the vibroacoustic signal generated during joint movement analysis. Seventy-three patients (30 with chondromalacia, 21 with lateral patellar compression syndrome, and 22 with osteoarthritis) and 32 healthy controls were tested during flexion/extension knee motion for vibroacoustic signals using an acceleration sensor. Estimated parameters: variation of mean square (VMS), difference between mean of four maximum and mean of four minimum values (R4), power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) were analyzed. Vibroacoustic signals recorded for particular disorders were characterized by significantly higher values of parameters in comparison to the control group. Moreover, differences were found among the various types of patellofemoral joint disturbances. Chondromalacia and osteoarthritis groups showed differences in all parameters examined. In addition, osteoarthritis patients exhibited differences in VMS, P1 and P2 values in comparison to lateral patellar compression syndrome patients. However, only the value of R4 was found to differ between knees with lateral patellar compression syndrome and those with chondromalacia. Our results suggest that particular disorders are characterized by specific vibroacoustic patterns of waveforms as well as values of analyzed parameters.

  1. An analysis of a joint shear model for jointed media with orthogonal joint sets; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Koteras, J.R.


    This report describes a joint shear model used in conjunction with a computational model for jointed media with orthogonal joint sets. The joint shear model allows nonlinear behavior for both joint sets. Because nonlinear behavior is allowed for both joint sets, a great many cases must be considered to fully describe the joint shear behavior of the jointed medium. An extensive set of equations is required to describe the joint shear stress and slip displacements that can occur for all the various cases. This report examines possible methods for simplifying this set of equations so that the model can be implemented efficiently form a computational standpoint. The shear model must be examined carefully to obtain a computationally efficient implementation that does not lead to numerical problems. The application to fractures in rock is discussed. 5 refs., 4 figs.

  2. High Temperature Plasticity of Bimetallic Magnesium and Aluminum Friction Stir Welded Joints (United States)

    Regev, Michael; El Mehtedi, Mohamad; Cabibbo, Marcello; Quercetti, Giovanni; Ciccarelli, Daniele; Spigarelli, Stefano


    The high temperature deformation of a bimetallic AZ31/AA6061 Friction Stir Welded joint was investigated in the present study by constant load creep experiments carried out at 473 K (200 °C). The microstructural analysis revealed the strongly inhomogeneous nature of the weld, which was characterized by an extremely fine grain size in the magnesium-rich zones and by the extensive presence of intermetallic phases. In the high stress regime, the creep strain was concentrated in the refined and particle-rich microstructure of the weld zone, while the AA6061 base metal remained undeformed. In the low stress regime, deformation became more homogeneously distributed between the AZ31 base metal and the weld zone. The creep behavior of the weld was found to obey the constitutive equation describing the minimum creep rate dependence on applied stress for the base AZ31, slightly modified to take into account the finer microstructure and the role of secondary phase particles, i.e., the retardation of grain growth and the obstruction of grain boundary sliding.

  3. Joint spatiotemporal variability of global sea surface temperatures and global Palmer drought severity index values (United States)

    Apipattanavis, S.; McCabe, G.J.; Rajagopalan, B.; Gangopadhyay, S.


    Dominant modes of individual and joint variability in global sea surface temperatures (SST) and global Palmer drought severity index (PDSI) values for the twentieth century are identified through a multivariate frequency domain singular value decomposition. This analysis indicates that a secular trend and variability related to the El Niño–Southern Oscillation (ENSO) are the dominant modes of variance shared among the global datasets. For the SST data the secular trend corresponds to a positive trend in Indian Ocean and South Atlantic SSTs, and a negative trend in North Pacific and North Atlantic SSTs. The ENSO reconstruction shows a strong signal in the tropical Pacific, North Pacific, and Indian Ocean regions. For the PDSI data, the secular trend reconstruction shows high amplitudes over central Africa including the Sahel, whereas the regions with strong ENSO amplitudes in PDSI are the southwestern and northwestern United States, South Africa, northeastern Brazil, central Africa, the Indian subcontinent, and Australia. An additional significant frequency, multidecadal variability, is identified for the Northern Hemisphere. This multidecadal frequency appears to be related to the Atlantic multidecadal oscillation (AMO). The multidecadal frequency is statistically significant in the Northern Hemisphere SST data, but is statistically nonsignificant in the PDSI data.

  4. Joint fractional Fourier analysis of wavefront-coding systems. (United States)

    Barwick, Shane; Finnigan, Jerome S


    The analysis of wavefront-coding systems is explored via the joint fractional Fourier signal representation (JFF) of the pupil function. The properties of the JFF of the pupil function are presented and are shown to be revealing with regard to the system response to defocus. Numerical examples that illustrate the properties are given.

  5. Calculation of Temperature in Sliding Joint Designed as a Part of Foundation Structure

    Directory of Open Access Journals (Sweden)

    Cajka Radim


    Full Text Available In case of expected horizontal deformation of subsoil or foundation structure it is possible to use rheological asphalt sliding joint to eliminate internal forces caused with friction. Material characteristics of asphalt are temperature sensitive. In science literature it is possible to find data with temperatures expected in footing bottom, however it was decided to complement this information with temperatures measured in-situ in foundation slab for super-computer building in campus of VŠB-Technical University of Ostrava. In the paper measured and calculated temperatures are compared for the first days after concreting the foundation structure. Besides the temperature of environment also significant influence of heat of cement hydration are taken into account.

  6. Adhesive Characterization and Progressive Damage Analysis of Bonded Composite Joints (United States)

    Girolamo, Donato; Davila, Carlos G.; Leone, Frank A.; Lin, Shih-Yung


    The results of an experimental/numerical campaign aimed to develop progressive damage analysis (PDA) tools for predicting the strength of a composite bonded joint under tensile loads are presented. The PDA is based on continuum damage mechanics (CDM) to account for intralaminar damage, and cohesive laws to account for interlaminar and adhesive damage. The adhesive response is characterized using standard fracture specimens and digital image correlation (DIC). The displacement fields measured by DIC are used to calculate the J-integrals, from which the associated cohesive laws of the structural adhesive can be derived. A finite element model of a sandwich conventional splice joint (CSJ) under tensile loads was developed. The simulations indicate that the model is capable of predicting the interactions of damage modes that lead to the failure of the joint.

  7. High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems (United States)

    Locci, Ivan E.; Nesbitt, James A.; Ritzert, Frank J.; Bowman, Cheryl L.


    Future generations of power systems for spacecraft and lunar surface systems will likely require a strong dependence on nuclear power. The design of a space nuclear power plant involves integrating together major subsystems with varying materia1 requirements. Refractory alloys are repeatedly considered for major structural components in space power reactor designs because refractory alloys retain their strength at higher temperatures than other classes of metals. The relatively higher mass and lower ductility of the refractory alloys make them less attractive for lower temperature subsystems in the power plant such as the power conversion system. The power conversion system would consist more likely of intermediate temperature Ni-based superalloys. One of many unanswered questions about the use of refractory alloys in a space power plant is how to transition from the use of the structural refractory alloy to more traditional structural alloys. Because deleterious phases can form when complex alloys are joined and operated at elevated temperatures, dissimilar material diffusion analyses of refractory alloys and superalloys are needed to inform designers about options of joint temperature and operational lifetime. Combinations of four superalloys and six refractory alloys were bonded and annealed at 1150 K and 1300 K to examine diffusional interactions in this study. Joints formed through hot pressing and hot isostatic pressing were compared. Results on newer alloys compared favorably to historical data. Diffusional stability is promising for some combinations of Mo-Re alloys and superalloys at 1150 K, but it appears that lower joint temperatures would be required for other refractory alloy couples.

  8. Finite element analysis study on the thermomechanical stability of thermal compression bonding (TCB) joints in tubular sodium sulfur cells (United States)

    Jung, Keeyoung; Lee, Solki; Park, Yoon-Cheol; Kim, Chang-Soo


    A typical large capacity sodium sulfur (NaS) battery is operated at 300-350 °C with 20-50 °C thermal fluctuations during its charging and discharging. In addition, for maintenance purposes, the cell experiences larger temperature changes down to the intermediate or room temperatures. Such temperature changes can cause mechanical failure of heterogeneous joints such as thermal compression bonding (TCB) joints, which is one of the most critical issues in developing NaS batteries. The present study seeks to build a computational finite element analysis (FEA) model to predict the thermomechanical responses of NaS batteries to the attack induced by the temperature changes. Specifically, the thermomechanical stress accumulation at TCB joints of a tubular cell has been explored during its booting-and-shutdown cycles. Static temperature profiles and simplified friction conditions in the cathode wall were assumed for the model. Using the developed model, the stress components that dominantly contribute the stress accumulation at the joint were identified, and the effects of TCB geometries and container material types on the thermal stress accumulation at the TCB joints were carefully examined. It turns out that the stress accumulation at the bonding interface would be critical for the failure at the TCB joints.

  9. Effect of Temperature on Microstructure and Fracture Mechanisms in Friction Stir Welded Al6061 Joints (United States)

    Dorbane, A.; Ayoub, G.; Mansoor, B.; Hamade, R. F.; Imad, A.


    Aluminum and its alloys are widely used in different industries due to such attractive properties as adequate strength, ductility, and low density. It is desirable to characterize welds of aluminum alloys obtained using "friction stir welding" at high temperatures. Al-to-Al (both 6061-T6) butt joints are produced by friction stir welding at tool rotation speed of 1600 rpm and four levels of tool advancing speeds: 250, 500, 750, and 1000 mm/min. Microstructural properties of the different welds are investigated. Observed are noticeable differences in microstructure characteristics between the various weld zones. Mechanical properties of these welded joints are characterized under tensile tests at temperatures of 25, 100, 200, and 300 °C, at a constant strain rate of 10-3/s. The optimum microstructural and mechanical properties were obtained for the samples FS welded with 1600 rpm tool rotation speed at 1000 mm/min tool advancing speed. The studied welds exhibited yield strength, ultimate tensile strength, and strain to failure with values inferior of those of the base material. Observations of postmortem samples revealed that in the temperature range of 25-200 °C the locus of failure originates at the region between the thermo-mechanically affected zone and the heat-affected zones. However, at higher temperatures (300 °C), the failure occurs in the stir zone. A change in the crack initiation mechanism with temperature is suggested to explain this observation.

  10. Kinetic analysis of the human knee joint

    Directory of Open Access Journals (Sweden)

    E Wiczkowski


    Full Text Available The pathology of the calcaneal (Achilles tendon constitutes a serious therapeutical and social problem. Indeed, this tendon is the strongest plantar flexor of the foot that plays an important role in the humangait. Although well known for a long time, no explicit description of the spontaneous subcutaneous rupture of the Achilles tendon can be found in medical or biomechanical literature. So far, neither pathomechanism nor the underlying causes of the tendon’s disruption have been fully elucidated. Many authors concentrate mostly on medical and biological aspects of the condition. The commonly held view is that it is the vascular supply to the tendon that plays a crucial role in pathogenesis of the tendon’s injuries. In fact, the vasculature a change with time and after the age of 30 is significantly reduced leading to the development of regressive alterations within as well as the decrement of the mechanical strength of the tendon. Obviously, interdisciplinary approach encompassing not only medical and biological but also the broadly taken mechanical viewpoint is needed to more comprehensively describe and explain this phenomenon. In the present paper, kinetic analysis of the knee was employed to define the trajectory of the point of initial insertion of the medial head of gastrocnemius, which was then used to determine the point’s route within the motor area extending from the flexion to the full extension of the knee. The obtained data on the trajectory are further utilized to present and define the pathomechanism of the spontaneous rupture of the calcaneal tendon.

  11. Joint time frequency analysis in digital signal processing

    DEFF Research Database (Denmark)

    Pedersen, Flemming

    In order to obtain simultaneous time and frequency energy distribution of a signal, Joint Time Frequency Analysis (JFTA) is often employed. The standard method is the Fourier Spectogram where the time and frequency resolution can be adjusted by changing a window function. A problem with this tech......In order to obtain simultaneous time and frequency energy distribution of a signal, Joint Time Frequency Analysis (JFTA) is often employed. The standard method is the Fourier Spectogram where the time and frequency resolution can be adjusted by changing a window function. A problem...... with this technique is that the resolution is limited because of distortion. To overcome the resolution limitations of the Fourier Spectogram, many new distributions have been developed. In spite of this the Fourier Spectogram is by far the prime method for the analysis of signals whose spectral content is varying...

  12. Diagnostic development for determining the joint temperature/soot statistics in hydrocarbon-fueled pool fires : LDRD final report.

    Energy Technology Data Exchange (ETDEWEB)

    Casteneda, Jaime N.; Frederickson, Kraig; Grasser, Thomas W.; Hewson, John C.; Kearney, Sean Patrick; Luketa, Anay Josephine


    A joint temperature/soot laser-based optical diagnostic was developed for the determination of the joint temperature/soot probability density function (PDF) for hydrocarbon-fueled meter-scale turbulent pool fires. This Laboratory Directed Research and Development (LDRD) effort was in support of the Advanced Simulation and Computing (ASC) program which seeks to produce computational models for the simulation of fire environments for risk assessment and analysis. The development of this laser-based optical diagnostic is motivated by the need for highly-resolved spatio-temporal information for which traditional diagnostic probes, such as thermocouples, are ill-suited. The in-flame gas temperature is determined from the shape of the nitrogen Coherent Anti-Stokes Raman Scattering (CARS) signature and the soot volume fraction is extracted from the intensity of the Laser-Induced Incandescence (LII) image of the CARS probed region. The current state of the diagnostic will be discussed including the uncertainty and physical limits of the measurements as well as the future applications of this probe.

  13. Microstructure Evolution of Cu-Cored Sn Solder Joints Under High Temperature and High Current Density (United States)

    Sa, Xianzhang; Wu, Ping


    This work investigated the microstructure evolution of Cu-cored Sn solder joints under high temperature and high current density. The Cu6Sn5 phase formed at both the Cu core/Sn interface and Cu wire/Sn interface right after reflow and grew with increasing annealing time, while the Cu3Sn phase formed and grew at the Cu/Cu6Sn5 interfaces. Intermetallic compound (IMC) growth followed a linear relationship with the square root of annealing time due to a diffusion-controlled mechanism. Under high current density, the thickness of the interfacial IMCs of the Cu core/Sn interface at the cathode side increased and the Cu core/Sn interface at the anode side exhibited an irregular and serrated morphology with prolonged current stressing time. Finite-element simulation was carried out to obtain the distribution of current density in the solder joint. Since Cu has lower resistivity, the electrical current primarily selected the Cu core as its electrical path, resulting in current crowding at the Cu core and the region between the Cu core and Cu wire. Compared with the conventional solder joint, the electromigration (EM) lifetime of the Cu-cored solder joint was much longer.

  14. Microstructure and mechanical analysis of W/P91 steel HIP-joint with Ti interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ji-chao [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Wang, Wanjing, E-mail: [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Sun, Zhaoxuan; Wang, Xingli; Wei, Ran [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Xie, Chunyi; Li, Qiang [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Luo, Guang-nan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Science Island Branch of Graduate School, University of Science & Technology of China, Hefei, 230031 (China); Hefei Center for Physical Science and Technology, Hefei, 230022 (China); Hefei Science Center of Chinese Academy of Sciences, Hefei, 230027 (China)


    Highlights: • W and P91 steel can be joined successfully using the Hot Isostatic Pressing (HIP) method with Ti interlayer. • The experiment was conducted at 760 °C below the P91 steel austenitizing temperature with the pressure 150 MPa for 4 h. • The residual stress concentration is responsible for the fracture of HIP joints under low joining temperature. • Low temperature can reduce the reaction products and improve the mechanical properties of W/Ti/P91 steel joints. - Abstract: W and P91 steel were joined by using the Hot Isostatic Pressing method with Ti interlayer, and the experiments were conducted at 760 °C. The mechanical property, bonding quality and interface microstructure were tested by the Torsion test, Non-Destructive Test, Scanning Electron Microscope and Nano-indentation test. The minimum shear strength of joints was 225 MPa and the failure occurred at the W/Ti interfaces. Metallographic analysis revealed good bonding quality across bonding lines. Almost no reaction products were found in the diffusion region and the Nano-indentation test demonstrated that the solid solution strengthening was caused by inter-diffusion in the diffusion zone. The effect of low joining temperature on reducing reaction products and improving mechanical properties of W/Ti/Steel diffusion bonding were investigated in this paper.

  15. Calculation of the temperature of asphalt concrete at making the joints of multilane road pavement of non-rigid type

    Directory of Open Access Journals (Sweden)

    Giyasov Botir Iminzhonovich


    Full Text Available The construction quality of road surface of non-rigid type essentially depend on providing the temperature regimes in the process of laying and packing of hot asphalt concrete mixtures. In order to provide the required characteristics of asphalt concrete due to the surface width it is necessary to provide the temperature regimes of hot asphalt concrete mixture in the zones of lane connection. The hot mixture is promptly cooling right after laying within several minutes, which results, according to the construction technology and the specific conditions of work production, in temperature abuse of the mixture at joints of the lanes at packing. The authors present the analysis of the technology of arranging multilane road surface by one paver with the possibility of heating the surface lane edge with the temperature of the adjacent lane. The results of the studies of the production conditions effect on the temperature of edge heating of the previously laid lanes, and the time required to achieve the maximum heating temperature depending on the relative thickness of coating layers.

  16. Strategic Joint Staff Force Posture and Readiness Process Analysis (United States)


    assessed against standardised Measures of Capability (Annex C) in terms of: Scale of Effect Survivability Reach Persistence Strategic varied to test the capabilities using the same resources organized differently. A further complementary analysis process is being established which...consider using the standardised Measures of Capability and the PRICIE metrics. Other DND Information System Data 51. Moving forward, the FP&R process

  17. Asymmetric joint multifractal analysis in Chinese stock markets (United States)

    Chen, Yuwen; Zheng, Tingting


    In this paper, the asymmetric joint multifractal analysis method based on statistical physics is proposed to explore the asymmetric correlation between daily returns and trading volumes in Chinese stock markets. The result shows asymmetric multifractal correlations exist between return and trading volume in Chinese stock markets. Moreover, when the stock indexes are upward, the fluctuations of returns are always weaker than when they are downward, whether the trading volumes are more or less.

  18. Joint optimization of algorithmic suites for EEG analysis. (United States)

    Santana, Eder; Brockmeier, Austin J; Principe, Jose C


    Electroencephalogram (EEG) data analysis algorithms consist of multiple processing steps each with a number of free parameters. A joint optimization methodology can be used as a wrapper to fine-tune these parameters for the patient or application. This approach is inspired by deep learning neural network models, but differs because the processing layers for EEG are heterogeneous with different approaches used for processing space and time. Nonetheless, we treat the processing stages as a neural network and apply backpropagation to jointly optimize the parameters. This approach outperforms previous results on the BCI Competition II - dataset IV; additionally, it outperforms the common spatial patterns (CSP) algorithm on the BCI Competition III dataset IV. In addition, the optimized parameters in the architecture are still interpretable.

  19. The analysis of adhesively bonded advanced composite joints using joint finite elements (United States)

    Stapleton, Scott E.

    The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

  20. The Analysis of Adhesively Bonded Advanced Composite Joints Using Joint Finite Elements (United States)

    Stapleton, Scott E.; Waas, Anthony M.


    The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

  1. Joint additive effects of temperature and UVB radiation on zoeae of the crab Taliepus dentatus

    KAUST Repository

    Carreja, B


    Warming and enhanced ultraviolet B (UVB) radiation are 2 global stressors acting across the ocean. We tested their effects on the survival and performance (consumption rates and activity) on the zoea I stage of the Chilean kelp crab Taliepus dentatus. Our goal was to resolve whether these stressors, when acting concurrently, had additive or interactive effects, either synergistic or antagonistic. A multifactorial experiment of 4 temperatures and 3 UVB irradiance levels was run. The larvae showed a significant increase in mortality with increasing temperature. Exposure to UVB reduced the thermal tolerance of the larvae by a significant increase of their mortality rate. Oxygen consumption increased as temperature increased. When exposed to UVB radiation, larval oxygen consumption increased significantly for all the temperatures tested. Two statistical models of joint effects confirmed that the combined effect of both stressors was additive, with no interaction, either synergistic or antagonistic. One of them, the independent action (IA) model, also revealed that concurrent effects on mortality remained additive when doubling the UVB dose. Additivity of the stressors improved the predictability of their effects on larval mortality. Exposure to UVB radiation increased mortality rates by 1.5 times at any temperature tested, independently of the dose. © The authors 2016.

  2. IMU-based joint angle measurement for gait analysis. (United States)

    Seel, Thomas; Raisch, Jörg; Schauer, Thomas


    This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments. After a review of available methods that may cope with this challenge, we present a set of new methods for: (1) joint axis and position identification; and (2) flexion/extension joint angle measurement. In particular, we propose methods that use only gyroscopes and accelerometers and, therefore, do not rely on a homogeneous magnetic field. We provide results from gait trials of a transfemoral amputee in which we compare the inertial measurement unit (IMU)-based methods to an optical 3D motion capture system. Unlike most authors, we place the optical markers on anatomical landmarks instead of attaching them to the IMUs. Root mean square errors of the knee flexion/extension angles are found to be less than 1° on the prosthesis and about 3° on the human leg. For the plantar/dorsiflexion of the ankle, both deviations are about 1°.

  3. IMU-Based Joint Angle Measurement for Gait Analysis

    Directory of Open Access Journals (Sweden)

    Thomas Seel


    Full Text Available This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments. After a review of available methods that may cope with this challenge, we present a set of new methods for: (1 joint axis and position identification; and (2 flexion/extension joint angle measurement. In particular, we propose methods that use only gyroscopes and accelerometers and, therefore, do not rely on a homogeneous magnetic field. We provide results from gait trials of a transfemoral amputee in which we compare the inertial measurement unit (IMU-based methods to an optical 3D motion capture system. Unlike most authors, we place the optical markers on anatomical landmarks instead of attaching them to the IMUs. Root mean square errors of the knee flexion/extension angles are found to be less than 1° on the prosthesis and about 3° on the human leg. For the plantar/dorsiflexion of the ankle, both deviations are about 1°.

  4. Joint analysis of spikes and local field potentials using copula. (United States)

    Hu, Meng; Li, Mingyao; Li, Wu; Liang, Hualou


    Recent technological advances, which allow for simultaneous recording of spikes and local field potentials (LFPs) at multiple sites in a given cortical area or across different areas, have greatly increased our understanding of signal processing in brain circuits. Joint analysis of simultaneously collected spike and LFP signals is an important step to explicate how the brain orchestrates information processing. In this contribution, we present a novel statistical framework based on Gaussian copula to jointly model spikes and LFP. In our approach, we use copula to link separate, marginal regression models to construct a joint regression model, in which the binary-valued spike train data are modeled using generalized linear model (GLM) and the continuous-valued LFP data are modeled using linear regression. Model parameters can be efficiently estimated via maximum-likelihood. In particular, we show that our model offers a means to statistically detect directional influence between spikes and LFP, akin to Granger causality measure, and that we are able to assess its statistical significance by conducting a Wald test. Through extensive simulations, we also show that our method is able to reliably recover the true model used to generate the data. To demonstrate the effectiveness of our approach in real setting, we further apply the method to a mixed neural dataset, consisting of spikes and LFP simultaneously recorded from the visual cortex of a monkey performing a contour detection task. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Reliability of Sn-3.5Ag Solder Joints in High Temperature Packaging Applications

    Energy Technology Data Exchange (ETDEWEB)

    Muralidharan, Govindarajan [ORNL; Kurumaddali, Nalini Kanth [ORNL; Kercher, Andrew K [ORNL; Leslie, Dr Scott [Powerex Inc


    There is a significant need for next generation, high performance power electronic packages and systems with wide band gap devices to operate at high temperatures in automotive and electricity transmission applications. Sn-3.5Ag solder is a candidate for use in such packages with potential operating temperatures up to 200oC. However, there is a need to understand thermal cycling reliability of Sn-3.5Ag solders subject to such operating conditions. The results of a study on the damage evolution occurring in large area Sn-3.5Ag solders joints between silicon dies and DBC substrates subject to thermal cycling between 200oC and 5oC is presented in this paper. Damage accumulation was followed using high resolution X-ray radiography techniques while nonlinear finite element models were developed based on the mechanical property data available in literature to understand the relationship between the stress state within the solder joint and the damage evolution occurring under thermal cycling conditions. It was observed that regions of damage observed in the experiments do not correspond to the finite element predictions of the location of regions of maximum plastic work.

  6. Antibiotic prophylaxis for haematogenous bacterial arthritis in patients with joint disease: a cost effectiveness analysis

    NARCIS (Netherlands)

    P. Krijnen (Pieta); C.J. Kaandorp; E.W. Steyerberg (Ewout); D. van Schaardenburg (Dirkjan); H.J. Moens; J.D.F. Habbema (Dik)


    textabstractOBJECTIVE: To assess the cost effectiveness of antibiotic prophylaxis for haematogenous bacterial arthritis in patients with joint disease. METHODS: In a decision analysis, data from a prospective study on bacterial arthritis in 4907 patients with joint


    Directory of Open Access Journals (Sweden)

    Mariusz Kłonica


    Full Text Available The aim of this study was a comparative analysis of static shear strength of single-lap adhesive joints of 316L steel adherends, measured prior to and after mechanical treatment with a P320 grit coated abrasive tool. The study was of comparative nature and focused on adhesive joints subjected to thermal cycling. The tests were carried out on joints bonded with Epidian 5 and Epidian 6 epoxy adhesives hardened with Z1 and PAC curing agents. The static shear strength tests results of single-lap adhesive joints were analysed with regard to different surface treatment variants. The scope of tests covered a relatively short fatigue cycle, i.e. 200 cycles in the range of temperatures between -40oC and +60oC. This paper includes the surface free energy and selected surface roughness parameters of substrates and images showing the surface of adherends before and after mechanical treatment with P320 grit coated abrasive tool.

  8. Numerical evaluation of multipass welding temperature field in API 5L X80 steel welded joints

    Directory of Open Access Journals (Sweden)

    J Nóbrega


    Full Text Available Many are the metallurgical changes suffered by materials when subjected to welding thermal cycle, promoting a considerable influence on the welded structures thermo mechanical properties. In project phase, one alternative for evaluating the welding cycle variable, would be the employment of computational methods through simulation. So, this paper presents an evaluation of the temperature field in a multipass welding of API 5L X80 steel used for oil and gas transportation, using the ABAQUS ® software, based on Finite Elements Method (FEM. During the simulation complex phenomena are considerable including: Variation in physical and mechanical properties of materials as a function of temperature, welding speed and the different mechanisms of heat exchange with the environment (convection and radiation were used. These considerations allow a more robust mathematical modeling for the welding process. An analytical heat source proposed by Goldak, to model the heat input in order to characterize the multipass welding through the GTAW (Gas Tungsten Arc Welding process on root and the SMAW (Shielded Metal Arc Welding process for the filling passes were used. So, it was possible to evaluate the effect of each welding pass on the welded joint temperature field, through the temperature peaks and cooling rates values during the welding process.

  9. Joint regression analysis and AMMI model applied to oat improvement (United States)

    Oliveira, A.; Oliveira, T. A.; Mejza, S.


    In our work we present an application of some biometrical methods useful in genotype stability evaluation, namely AMMI model, Joint Regression Analysis (JRA) and multiple comparison tests. A genotype stability analysis of oat (Avena Sativa L.) grain yield was carried out using data of the Portuguese Plant Breeding Board, sample of the 22 different genotypes during the years 2002, 2003 and 2004 in six locations. In Ferreira et al. (2006) the authors state the relevance of the regression models and of the Additive Main Effects and Multiplicative Interactions (AMMI) model, to study and to estimate phenotypic stability effects. As computational techniques we use the Zigzag algorithm to estimate the regression coefficients and the agricolae-package available in R software for AMMI model analysis.

  10. Analysis of the affected joints in rheumatoid arthritis patients in a large Japanese cohort. (United States)

    Kanazawa, Teruhisa; Nishino, Jinju; Tohma, Shigeto; Tanaka, Sakae


    Rheumatoid arthritis (RA) is a chronic inflammatory disorder involving multiple joints. We investigated the distribution of the affected joints and the relationships among this distribution, the disease activity, and the disease duration in Japanese RA patients by cross-sectional analysis using the National Database of Rheumatic Diseases by iR-net in Japan. A total of 6408 RA patients registered in the database were analyzed. In each patient, the location of joint swelling and joint tenderness of 68 joints was examined, and the relationships among the distribution of the affected joints, the disease activity as determined using the DAS28-ESR, and the disease duration were analyzed statistically. For the 6408 RA patients examined, the wrist was the most frequently affected site. There were some differences in the prevalence of tenderness and swelling; tenderness was frequently observed in large joints such as the knee, elbow and shoulder, while swelling was frequently observed in small joints such as the metacarpophalangeal joints. Although the frequency of involvement increased in all joints as disease activity increased, the pattern of distribution was not affected by disease activity. Furthermore, the distribution was not influenced by disease duration. Based on the results of this study, we can draw the following conclusions: (1) the wrist was the most affected joint; (2) there was a discrepancy between the distribution of swollen joints and that of tender joints; and (3) the distribution of affected joints was uniform regardless of disease activity.

  11. Experimental and theoretical analysis of joints in turbochargers. Investigation of the transmission characteristics of turbocharger joints; Experimentelle und analytische Fuegestellenanalyse am Abgasturbolader. Untersuchung des Uebertragungsverhaltens von Fuegestellen am Abgasturbolader

    Energy Technology Data Exchange (ETDEWEB)

    Swoboda, Stefan


    The author attempted a systematic analysis of the structural dynamics of a turbocharger with special attention to the properties of joints, which were identified by experimental analyses of single-component and multicomponent systems. Boundary conditions of operation like turbocharger temperature and speed as well as structure-borne and airborne noise were considered in the analyses. Further, structural dynamic interactions between the turbocharger and the engine components connected by joints, e.g. oil recirculation and diesel particulate filter, were investigated. For the simulations of the structural dynamics of the turbocharger, the turbocharger housing was modelled in ABAQUS using a FE model based on CAD data; the joints were implemented as ''coupling elements'' between the components. The simulation results were then correlated with the experimental findings in an iterative process. Supplementary vibration analyses of the simulation model with optimized joint characteristics showed the structure-dynamic properties of the transmission functions of the joints. (orig.)

  12. Heel effects on joint contact force components in the equine digit : a sensitivity analysis


    Noble, Prisca; Lejeune, Jean-Philippe; Caudron, Isabelle; Lejeune, Pascal; Collin, Bernard; Denoix, Jean-Marie; Serteyn, Didier


    Reasons for performing study: Whereas the effect of heel configuration on the tension of the suspensory apparatus is well documented in the literature, there are few reports of joint contact force components in the equine distal forelimb. Objectives: To improve understanding of the effect of heel configuration on equine digit joint loading, a sensitivity analysis was performed to compare the effect of a raised heel on joint contact force components in the coffin and fetlock joints during ...

  13. Nonlinear Analysis of Bonded Composite Single-LAP Joints (United States)

    Oterkus, E.; Barut, A.; Madenci, E.; Smeltzer, S. S.; Ambur, D. R.


    This study presents a semi-analytical solution method to analyze the geometrically nonlinear response of bonded composite single-lap joints with tapered adherend edges under uniaxial tension. The solution method provides the transverse shear and normal stresses in the adhesive and in-plane stress resultants and bending moments in the adherends. The method utilizes the principle of virtual work in conjunction with von Karman s nonlinear plate theory to model the adherends and the shear lag model to represent the kinematics of the thin adhesive layer between the adherends. Furthermore, the method accounts for the bilinear elastic material behavior of the adhesive while maintaining a linear stress-strain relationship in the adherends. In order to account for the stiffness changes due to thickness variation of the adherends along the tapered edges, their in-plane and bending stiffness matrices are varied as a function of thickness along the tapered region. The combination of these complexities results in a system of nonlinear governing equilibrium equations. This approach represents a computationally efficient alternative to finite element method. Comparisons are made with corresponding results obtained from finite-element analysis. The results confirm the validity of the solution method. The numerical results present the effects of taper angle, adherend overlap length, and the bilinear adhesive material on the stress fields in the adherends, as well as the adhesive, of a single-lap joint

  14. Influence of temperature and exploitation period on fatigue crack growth parameters in different regions of welded joints

    Directory of Open Access Journals (Sweden)

    Ivica Camagic


    Full Text Available The influence of exploitation period and temperature on the fatigue crack growth parameters indifferent regions of a welded joint is analysed for new and exploited low-alloyed Cr-Mo steel A-387 Gr. B. The parent metal is a part of a reactor mantle which was exploited for over 40 years, and recently replaced with new material. Fatigue crack growth parameters, threshold value Kth, coefficient C and exponent m, have been determined, both at room and exploitation temperature. Based on testing results, fatigue crack growth resistance in different regions of welded joint is analysed in order to justify the selected welding procedure specification.

  15. Jointly Learning Structured Analysis Discriminative Dictionary and Analysis Multiclass Classifier. (United States)

    Zhang, Zhao; Jiang, Weiming; Qin, Jie; Zhang, Li; Li, Fanzhang; Zhang, Min; Yan, Shuicheng


    In this paper, we propose an analysis mechanism-based structured analysis discriminative dictionary learning (ADDL) framework. The ADDL seamlessly integrates ADDL, analysis representation, and analysis classifier training into a unified model. The applied analysis mechanism can make sure that the learned dictionaries, representations, and linear classifiers over different classes are independent and discriminating as much as possible. The dictionary is obtained by minimizing a reconstruction error and an analytical incoherence promoting term that encourages the subdictionaries associated with different classes to be independent. To obtain the representation coefficients, ADDL imposes a sparse l2,1-norm constraint on the coding coefficients instead of using l₀ or l₁ norm, since the l₀- or l₁-norm constraint applied in most existing DL criteria makes the training phase time consuming. The code-extraction projection that bridges data with the sparse codes by extracting special features from the given samples is calculated via minimizing a sparse code approximation term. Then we compute a linear classifier based on the approximated sparse codes by an analysis mechanism to simultaneously consider the classification and representation powers. Thus, the classification approach of our model is very efficient, because it can avoid the extra time-consuming sparse reconstruction process with trained dictionary for each new test data as most existing DL algorithms. Simulations on real image databases demonstrate that our ADDL model can obtain superior performance over other state of the arts.

  16. Thermo-mechanic and Microstructural Analysis of an Underwater Welding Joint

    Directory of Open Access Journals (Sweden)

    Pedro Hernández Gutiérrez

    Full Text Available Abstract The aim of this research is to present a comparative analysis between theoretical and experimental thermal fields as well as a microstructural behaviour and residual stresses applying multiple weld beads in the joint of two API 5L X52 pipe sections. The thermal field, microstructural and residual stresses were numerically modelled through the finite element method (FEM and compared to experimentally. The simulation conditions used in the FEM analysis were similar considerations to the underwater welding conditions. The finite element analysis was carried out, first by a non-linear transient thermal analysis for obtaining the global temperature history generated during the underwater welding process. Subsequently, a microstructural behaviour was determined using the temperatures distribution obtained in the pipe material by calculating the structural transformations of the material during the welding process, and finally a stress analysis was developed using the temperatures obtained from the thermal analysis. It was found that this simulation method can be used efficiently to determinate with accuracy the optimum welding parameters of this kind of weld applications.

  17. Experimental And FE Analysis Of Eccentric Loaded Symmetrical And Unsymmetrical Bolted Joint With Bolt Pretension


    Pranav R. Pimpalkar; Prof. S. D. Khamankar


    This paper presents experimental and FE analysis of eccentric loaded bolted joint under symmetric and unsymmetrical bolt system with consider bolt pretension. A cad model of a bolted joint has been developed using modeling software PROE5.0 and FE analysis was carried out by using ANSYSWORKBENCH12.0.stress analysis has been carried out by varying bolt pattern of bolted joint for predict maximum heavily loaded bolt. Experimental work was conducted to measure maximum shear strengt...

  18. Failure Analysis in Space: International Space Station (ISS) Starboard Solar Alpha Rotary Joint (SARJ) Debris Analysis (United States)

    Long, V. S.; Wright, M. C.; McDanels, S. J.; Lubas, D.; Tucker, B.; Marciniak, P. J.


    This slide presentation reviews the debris analysis of the Starboard Solar Alpha Rotary Joint (SARJ), a mechanism that is designed to keep the solar arrays facing the sun. The goal of this was to identify the failure mechanism based on surface morphology and to determine the source of debris through elemental and particle analysis.

  19. Fatigue Fracture Analysis and Development of Fundamentals of Predictive NDE of Adhesive Composite Joints

    National Research Council Canada - National Science Library

    Dzenis, Y. A


    The objective of this research was a systematic fatigue fracture analysis and development of fundamentals of predictive nondestructive evaluation of adhesive composite joints for aerospace structural applications...

  20. Multi-Objective Analysis for Jointly Reducing Noise and Emissions via ATM/Aircraft Systems Project (United States)

    National Aeronautics and Space Administration — Leveraging extensive experience from Joint Planning and Development Office (JPDO) environmental analysis, Federal Aviation Administration (FAA) National Airspace...

  1. Analysis of temperature trends in Northern Serbia (United States)

    Tosic, Ivana; Gavrilov, Milivoj; Unkašević, Miroslava; Marković, Slobodan; Petrović, Predrag


    An analysis of air temperature trends in Northern Serbia for the annual and seasonal time series is performed for two periods: 1949-2013 and 1979-2013. Three data sets of surface air temperatures: monthly mean temperatures, monthly maximum temperatures, and monthly minimum temperatures are analyzed at 9 stations that have altitudes varying between 75 m and 102 m. Monthly mean temperatures are obtained as the average of the daily mean temperatures, while monthly maximum (minimum) temperatures are the maximum (minimum) values of daily temperatures in corresponding month. Positive trends were found in 29 out of 30 time series, and the negative trend was found only in winter during the period 1979-2013. Applying the Mann-Kendall test, significant positive trends were found in 15 series; 7 in the period 1949-2013 and 8 in the period 1979-2013; and no significant trend was found in 15 series. Significant positive trends are dominated during the year, spring, and summer, where it was found in 14 out of 18 cases. Significant positive trends were found 7, 5, and 3 times in mean, maximum and minimum temperatures, respectively. It was found that the positive temperature trends are dominant in Northern Serbia.


    Directory of Open Access Journals (Sweden)

    Pavel Kovačócy


    Full Text Available The article presents samples of weld joint of AISI 310 austenitic steel which were subjected to solution annealing at various temperature - time exposures. The objective of the experiment was to determine the annealing temperature so that the steel should not be sensitized. Tendency to intercrystalline corrosion was analysed by means of a corrosion test in 10 % oxalic acid according to ASTM A 262. At the temperatures of 1000 and 1100°C held for 15 min. the steel was not sensitized. At the temperature of 850°C the steel was sensitized, i.e. susceptible to intercrystalline corrosion.


    Directory of Open Access Journals (Sweden)

    Martina Nerádová


    Full Text Available The article presents samples of weld joint of AISI 310 austenitic steel which were subjected to solution annealing at various temperature - time exposures. The objective of the experiment was to determine the annealing temperature so that the steel should not be sensitized. Tendency to intercrystalline corrosion was analysed by means of a corrosion test in 10 % oxalic acid according to ASTM A 262. At the temperatures of 1000 and 1100°C held for 15 min. the steel was not sensitized. At the temperature of 850°C the steel was sensitized, i.e. susceptible to intercrystalline corrosion.

  4. Performance Analysis and Optimization of Dowels in Jointed Concrete Floors

    CERN Document Server

    Ghauch, Ziad; Tabbara, Mazen


    This study examines the performance of traditional round dowels in concrete floors and attempts to optimize the design of dowels through Finite Element (FE) analysis. A new type of Double-Tapered Round (DTR) dowels is proposed, and the performance of DTR dowels is compared to that of traditional cylindrical dowels. Linear Elastic (LE) analysis are performed in Abaqus (v-6.11) order to identify the optimized geometry of DTR dowels that would achieve (1) highest load transfer across adjacent slabs through shear action, and (2) lowest bearing stresses on the concrete. LE analyses are complemented by nonlinear FE analysis. The Riks method available in Abaqus/Standard, coupled with the Concrete Damaged Plasticity (CDP) model is used to simulate the degradation of concrete surrounding both DTR the traditional cylindrical dowels. Results obtained show that the use of DTR dowels can reduce bearing stresses at the face of the joint by as much 2.2 times as compared to traditional cylindrical dowels. While adequate load...

  5. The construction joint analysis of the villa Tugendhat interior furnishing

    Directory of Open Access Journals (Sweden)

    Zdeněk Holouš


    Full Text Available The functionalist villa Tugendhat in Brno is a first monument of modern architecture in the Czech Republic. This monument was registered in 2001 to the list of World Cultural and Natural Heritage by UNESCO. Among the most experts this building is usually regarded as a greatest work of German architect and designer Ludwig Mies van der Rohe. The complete renewal of this monument was ini­tia­ted due to unsatisfactory technical condition and because of the higher operational requirements. In this work we deal with the technical analysis of the villa Tugendhat interior furnishing, or more precisely with the structural analysis of its furniture joints. The goal of this work is to highlight the original construction and material solutions of the furniture in connection with the creation of production-technical documentation for the renewal. Project scope includes the complete constructional drawing documentation of the 53 pieces of furniture, documents relating to the surface treatment of the furniture, as well as documentation of manufacturing and constructional details. Described part of the project was prepared a few years ago by the Department of furniture, design and habitation. Nowadays, the project documentation is completed. Protracted legal disputes concerning this state contract still postpone the beginning of reconstruction of this monument.

  6. Localized component analysis for arthritis detection in the trapeziometacarpal joint

    NARCIS (Netherlands)

    van de Giessen, Martijn; de Raedt, Sepp; Stilling, Maiken; Hansen, Torben B.; Maas, Mario; Streekstra, Geert J.; van Vliet, Lucas J.; Vos, Frans M.


    The trapeziometacarpal joint enables the prehensile function of the thumb. Unfortunately, this joint is vulnerable to osteoarthritis (OA) that typically affects the local shape of the trapezium. A novel, local statistical shape model is defined that employs a differentiable locality measure based on

  7. Experimental and Numerical Failure Analysis of Adhesive Composite Joints

    Directory of Open Access Journals (Sweden)

    Farhad Asgari Mehrabadi


    Full Text Available In the first section of this work, a suitable data reduction scheme is developed to measure the adhesive joints strain energy release rate under pure mode-I loading, and in the second section, three types of adhesive hybrid lap-joints, that is, Aluminum-GFRP (Glass Fiber Reinforced Plastic, GFRP-GFRP, and Steel-GFRP were employed in the determination of adhesive hybrid joints strengths and failures that occur at these assemblies under tension loading. To achieve the aims, Double Cantilever Beam (DCB was used to evaluate the fracture state under the mode-I loading (opening mode and also hybrid lap-joint was employed to investigate the failure load and strength of bonded joints. The finite-element study was carried out to understand the stress intensity factors in DCB test to account fracture toughness using J-integral method as a useful tool for predicting crack failures. In the case of hybrid lap-joint tests, a numerical modeling was also performed to determine the adhesive stress distribution and stress concentrations in the side of lap-joint. Results are discussed in terms of their relationship with adhesively bonded joints and thus can be used to develop appropriate approaches aimed at using adhesive bonding and extending the lives of adhesively bonded repairs for aerospace structures.

  8. Riveted Lap Joints in Aircraft Fuselage Design, Analysis and Properties

    CERN Document Server

    Skorupa, Andrzej


    Fatigue of the pressurized fuselages of transport aircraft is a significant problem all builders and users of aircraft have to cope with for reasons associated with assuring a sufficient lifetime and safety, and formulating adequate inspection procedures. These aspects are all addressed in various formal protocols for creating and maintaining airworthiness, including damage tolerance considerations. In most transport aircraft, fatigue occurs in lap joints, sometimes leading to circumstances that threaten safety in critical ways. The problem of fatigue of lap joints has been considerably enlarged by the goal of extending aircraft lifetimes. Fatigue of riveted lap joints between aluminium alloy sheets, typical of the pressurized aircraft fuselage, is the major topic of the present book. The richly illustrated and well-structured chapters treat subjects such as: structural design solutions and loading conditions for fuselage skin joints; relevance of laboratory test results for simple lap joint specimens to rive...

  9. Joint Spectral Analysis for Early Bright X-ray Flares of -Ray Bursts ...

    Indian Academy of Sciences (India)

    A joint spectral analysis for early bright X-ray flares that were simultaneously observed with Swift BAT and XRT are present. Both BAT and XRT lightcurves of these flares are correlated. Our joint spectral analysis shows that the radiations in the two energy bands are from the same spectral component, which can be well ...

  10. The Effects of Unilateral Alloplastic Temporomandibular Joint Replacement on the Opposite-Side Natural Joint: A Finite-Element Analysis. (United States)

    Bekcioglu, Burak; Bulut, Emel; Bas, Burcu


    The purpose of this study was to evaluate the stress distribution on the temporomandibular joint (TMJ) prosthesis and contralateral natural TMJ with finite-element analysis. A TMJ implant was used to create a 3-dimensional model with a computer. This model was integrated with a mandible model created with a computer by use of computed tomography images, similar to a real TMJ replacement procedure. Masticatory loads were applied to the model. The loads transmitted to the TMJ prosthesis and contralateral healthy joint were evaluated by means of finite-element analysis. In the model without the TMJ prosthesis, maximum von Mises stress was 252.697 N/mm(2) at the condyle and 5.418 N/mm(2) at the disc. In the model with the unilateral TMJ prosthesis, maximum stress at the joint prosthesis was 792.681 N/mm(2). In the contralateral natural joint, maximum stress was 268.908 N/mm(2) at the condyle and 8.357 N/mm(2) at the disc. In the TMJ model with the unilateral total TMJ prosthesis, increased stress values were observed at the disc and condyle of the contralateral natural TMJ. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Measurement of the electron and ion temperatures by the x-ray imaging crystal spectrometer on joint Texas experimental tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Yan, W.; Chen, Z. Y., E-mail:; Huang, D. W.; Tong, R. H.; Wang, S. Y.; Wei, Y. N.; Ma, T. K.; Zhuang, G. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan (China); Jin, W. [Center of Interface Dynamics for Sustainability, China Academy of Engineering Physics, Chengdu, Sichuan 610200 (China); Lee, S. G. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Shi, Y. J. [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of)


    An x-ray imaging crystal spectrometer has been developed on joint Texas experimental tokamak for the measurement of electron and ion temperatures from the K{sub α} spectra of helium-like argon and its satellite lines. A two-dimensional multi-wire proportional counter has been applied to detect the spectra. The electron and ion temperatures have been obtained from the Voigt fitting with the spectra of helium-like argon ions. The profiles of electron and ion temperatures show the dependence on electron density in ohmic plasmas.

  12. Joint analysis of BICEP2/keck array and Planck Data. (United States)

    Ade, P A R; Aghanim, N; Ahmed, Z; Aikin, R W; Alexander, K D; Arnaud, M; Aumont, J; Baccigalupi, C; Banday, A J; Barkats, D; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Benton, S J; Bernard, J-P; Bersanelli, M; Bielewicz, P; Bischoff, C A; Bock, J J; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Brevik, J A; Bucher, M; Buder, I; Bullock, E; Burigana, C; Butler, R C; Buza, V; Calabrese, E; Cardoso, J-F; Catalano, A; Challinor, A; Chary, R-R; Chiang, H C; Christensen, P R; Colombo, L P L; Combet, C; Connors, J; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Delouis, J-M; Désert, F-X; Dickinson, C; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dowell, C D; Duband, L; Ducout, A; Dunkley, J; Dupac, X; Dvorkin, C; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Falgarone, E; Filippini, J P; Finelli, F; Fliescher, S; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Ghosh, T; Giard, M; Gjerløw, E; Golwala, S R; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Halpern, M; Hansen, F K; Hanson, D; Harrison, D L; Hasselfield, M; Helou, G; Henrot-Versillé, S; Herranz, D; Hildebrandt, S R; Hilton, G C; Hivon, E; Hobson, M; Holmes, W A; Hovest, W; Hristov, V V; Huffenberger, K M; Hui, H; Hurier, G; Irwin, K D; Jaffe, A H; Jaffe, T R; Jewell, J; Jones, W C; Juvela, M; Karakci, A; Karkare, K S; Kaufman, J P; Keating, B G; Kefeli, S; Keihänen, E; Kernasovskiy, S A; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Knox, L; Kovac, J M; Krachmalnicoff, N; Kunz, M; Kuo, C L; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J-M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leitch, E M; Leonardi, R; Levrier, F; Lewis, A; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Lueker, M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Mangilli, A; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Mason, P; Matarrese, S; Megerian, K G; Meinhold, P R; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M-A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Moss, A; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nguyen, H T; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; O'Brient, R; Ogburn, R W; Orlando, A; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Partridge, B; Pasian, F; Patanchon, G; Pearson, T J; Perdereau, O; Perotto, L; Pettorino, V; Piacentini, F; Piat, M; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Pratt, G W; Prunet, S; Pryke, C; Puget, J-L; Rachen, J P; Reach, W T; Rebolo, R; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Richter, S; Ristorcelli, I; Rocha, G; Rossetti, M; Roudier, G; Rowan-Robinson, M; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Schwarz, R; Scott, D; Seiffert, M D; Sheehy, C D; Spencer, L D; Staniszewski, Z K; Stolyarov, V; Sudiwala, R; Sunyaev, R; Sutton, D; Suur-Uski, A-S; Sygnet, J-F; Tauber, J A; Teply, G P; Terenzi, L; Thompson, K L; Toffolatti, L; Tolan, J E; Tomasi, M; Tristram, M; Tucci, M; Turner, A D; Valenziano, L; Valiviita, J; Van Tent, B; Vibert, L; Vielva, P; Vieregg, A G; Villa, F; Wade, L A; Wandelt, B D; Watson, R; Weber, A C; Wehus, I K; White, M; White, S D M; Willmert, J; Wong, C L; Yoon, K W; Yvon, D; Zacchei, A; Zonca, A


    We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400  deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2  μK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150  GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

  13. Joint Analysis of BICEP2/Keck Array and Planck Data (United States)

    BICEP2/Keck Collaboration; Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Ahmed, Z.; Aikin, R. W.; Alexander, K. D.; Arnaud, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barkats, D.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Benton, S. J.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bischoff, C. A.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Brevik, J. A.; Bucher, M.; Buder, I.; Bullock, E.; Burigana, C.; Butler, R. C.; Buza, V.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chary, R.-R.; Chiang, H. C.; Christensen, P. R.; Colombo, L. P. L.; Combet, C.; Connors, J.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; De Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dowell, C. D.; Duband, L.; Ducout, A.; Dunkley, J.; Dupac, X.; Dvorkin, C.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Filippini, J. P.; Finelli, F.; Fliescher, S.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Gjerløw, E.; Golwala, S. R.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Halpern, M.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Hasselfield, M.; Helou, G.; Henrot-Versillé, S.; Herranz, D.; Hildebrandt, S. R.; Hilton, G. C.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hovest, W.; Hristov, V. V.; Huffenberger, K. M.; Hui, H.; Hurier, G.; Irwin, K. D.; Jaffe, A. H.; Jaffe, T. R.; Jewell, J.; Jones, W. C.; Juvela, M.; Karakci, A.; Karkare, K. S.; Kaufman, J. P.; Keating, B. G.; Kefeli, S.; Keihänen, E.; Kernasovskiy, S. A.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kovac, J. M.; Krachmalnicoff, N.; Kunz, M.; Kuo, C. L.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leitch, E. M.; Leonardi, R.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Lueker, M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Mason, P.; Matarrese, S.; Megerian, K. G.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nguyen, H. T.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; O'Brient, R.; Ogburn, R. W.; Orlando, A.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Pettorino, V.; Piacentini, F.; Piat, M.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Pratt, G. W.; Prunet, S.; Pryke, C.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Richter, S.; Ristorcelli, I.; Rocha, G.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Schwarz, R.; Scott, D.; Seiffert, M. D.; Sheehy, C. D.; Spencer, L. D.; Staniszewski, Z. K.; Stolyarov, V.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Teply, G. P.; Terenzi, L.; Thompson, K. L.; Toffolatti, L.; Tolan, J. E.; Tomasi, M.; Tristram, M.; Tucci, M.; Turner, A. D.; Valenziano, L.; Valiviita, J.; van Tent, B.; Vibert, L.; Vielva, P.; Vieregg, A. G.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Watson, R.; Weber, A. C.; Wehus, I. K.; White, M.; White, S. D. M.; Willmert, J.; Wong, C. L.; Yoon, K. W.; Yvon, D.; Zacchei, A.; Zonca, A.; Bicep2/Keck; Planck Collaborations


    We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg2 patch of sky centered on RA 0 h, Dec. -57.5 ° . The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 μ K deg in Q and U at 143 GHz). We detect 150 ×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-Λ CDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r0.05confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0 σ significance.

  14. Analysis of Financial Ratio to Distinguish Indonesia Joint Venture General Insurance Company Performance using Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    Subiakto Soekarno


    Full Text Available Insurance industry stands as a service business that plays a significant role in Indonesiaeconomical condition. The development of insurance industry in Indonesia, both of generalinsurance and life insurance, has increased very fast. The general insurance industry itselfdivided into two major players which are local private company and Joint Venture Company.Lately, the use of statistical techniques and financial ratios models to asses financial institutionsuch as insurance company have been used as one of the appropriate combination inpredicting the performance of an industry. This research aims to distinguish between JointVenture General Insurance Companies that have a good performance and those who are lessperforming well using Discriminant Analysis. Further, the findings led that DiscriminantAnalysis is able to distinguish Joint Venture General Insurance Companies that have a goodperformance and those who are not performing well. There are also six ratios which are RBC,Technical Reserve to Investment Ratio, Debt Ratio, Return on Equity, Loss Ratio, and ExpenseRatio that stand as the most influential ratios to distinguish the performance of joint venturegeneral insurance companies. In addition, the result suggest business people to be concernedtoward those six ratios, to increase their companies’ performance.Key words: general insurance, financial ratio, discriminant analysis

  15. A temperature analysis in magnetic hyperthermia (United States)

    Astefanoaei, Iordana; Stancu, Alexandru


    In the Magnetic Hyperthermia - the control of the temperature field within the malignant tissues is an important task which receives a considerable attention in the all experimental and theoretical researches. A temperature analysis focus the main parameters which influences strongly this therapy. The spatial distribution of the particles influences significantly the temperature field developed within a malignant tissue, when an external time - dependent magnetic field is applied. This paper analyses the temperature field induced by the particulate systems (magnetite and maghemite) with an exponential spatial distribution within a concentric tissues configuration (malignant and healthy tissues). The temperature field developed by these magnetic systems was computed using an analytical model which predicts the temperature at every point. This model was developed in order to compute the isothermal surfaces in the range of the therapeutic temperature range: 42÷46°C. The parameters involved in the burning process of the malignant tissues are optimized to get the uniform hyperthermic temperatures within malignant tissues for a corresponding clinically particle dosage.

  16. 76 FR 34286 - ITS Joint Program Office; Webinar on Connected Vehicle Infrastructure Deployment Analysis Report... (United States)


    ... between vehicles, infrastructure, and personal communications devices to improve safety, mobility, and... ITS Joint Program Office; Webinar on Connected Vehicle Infrastructure Deployment Analysis Report... Connected Vehicle Infrastructure Deployment Analysis Report. The webinar will provide an opportunity for...

  17. Failure analysis of dissimilar single-lap joints

    Directory of Open Access Journals (Sweden)

    F.A. Stuparu


    Full Text Available Single-lap joints made of aluminium and carbon fibre adherends of different thickness are tested to understand better the behaviour of such dissimilar joints. The overlap length and the thickness of the adhesive are kept constant. Local deformation fields are onitored by using the digital image correlation method. Peeling and shearing strains are investigated, emphasizing that peeling is important in the region where failure is initiated, towards an extremity of the overlap region. The use of only carbon fibre adherends is not recommended for a smaller thickness as an additional interface failure is produced and compromises the integrity of the lap joint. However, a dissimilar joint (aluminium-carbon with smaller thickness adherends succeeds to maintain the stiffness of the assembly, but its strength is diminished. The obtained results are suggesting that a complete monitoring of the failure processes in the overlap region can be fully understood only if local deformation measurements are possible.

  18. Soft Smart Garments for Lower Limb Joint Position Analysis

    National Research Council Canada - National Science Library

    Massimo Totaro; Tommaso Poliero; Alessio Mondini; Chiara Lucarotti; Giovanni Cairoli; Jesùs Ortiz; Lucia Beccai


    ... electronics are embedded for retrieving movement of the specific joint. Stretchable capacitive sensors with a three-electrode configuration are built combining conductive textiles and elastomeric layers, and distributed around knee and ankle...

  19. Analysis of bed joint influence on masonry modulus of elasticity


    Zavalis, R.; Jonaitis, B.; Paulo B. Lourenço


    The means of determining the modulus of elasticity presented in technical literature often underestimate factors such as the influence of mechanical properties of the bed joint mortar and the influence of contact zone of the masonry unit and mortar on the elasticity modulus. Research carried out by the authors show that the modulus of elasticity of the bed joint considering influence of the contact zone (effective modulus of elasticity) is 3 to 25 times less than mortar modulus of...

  20. Joint venture versus outreach: a financial analysis of case studies. (United States)

    Forsman, R W


    Medical centers across the country are facing cost challenges, and national commercial laboratories are experiencing financial declines that necessitate their capturing market share in any way possible. Many laboratories are turning to joint ventures or partnerships for financial relief. However, it often is in the best interest of the patient and the medical center to integrate laboratory services across the continuum of care. This article analyzes two hypothetical joint ventures involving a laboratory management agreement and full laboratory outsourcing.

  1. Experimental and Numerical Analysis of Steel Joints in Round Wood

    Directory of Open Access Journals (Sweden)

    Mikolášek David


    Full Text Available The paper analyses a drawn steel joint in round logs for which several types of reinforcements have been proposed. The load-carrying capacity of the reinforcements have been tested in laboratories. At the same time, numerical modelling has been performed - it has focused, in particular, on rigidity of the joints during the loading process. Physical and geometrical nonlinearities have been taken into account. The Finite Element Method and 3D computation models have been used in the numerical calculations.

  2. Analysis of in-situ rock joint strength using digital borehole scanner images

    Energy Technology Data Exchange (ETDEWEB)

    Thapa, Bhaskar Bahadur [Univ. of California, Berkeley, CA (United States)


    The availability of high resolution digital images of borehole walls using the Borehole Scanner System has made it possible to develop new methods of in-situ rock characterization. This thesis addresses particularly new approaches to the characterization of in-situ joint strength arising from surface roughness. An image processing technique is used to extract the roughness profile from joints in the unrolled image of the borehole wall. A method for estimating in-situ Rengers envelopes using this data is presented along with results from using the method on joints in a borehole in porphyritic granite. Next, an analysis of the joint dilation angle anisotropy is described and applied to the porphyritic granite joints. The results indicate that the dilation angle of the joints studied are anisotropic at small scales and tend to reflect joint waviness as scale increases. A procedure to unroll the opposing roughness profiles to obtain a two dimensional sample is presented. The measurement of apertures during this process is shown to produce an error which increases with the dip of the joint. The two dimensional sample of opposing profiles is used in a new kinematic analysis of the joint shear stress-shear deformation behavior. Examples of applying these methods on the porphyritic granite joints are presented. The unrolled opposing profiles were used in a numerical simulation of a direct shear test using Discontinuous Deformation Analysis. Results were compared to laboratory test results using core samples containing the same joints. The simulated dilatancy and shear stress-shear deformation curves were close to the laboratory curves in the case of a joint in porphyritic granite.

  3. Finite element analysis of dovetail joint made with the use of CNC technology

    Directory of Open Access Journals (Sweden)

    Václav Sebera


    Full Text Available The objective of the paper is the parametrization and the finite element analysis of mechanical pro­per­ties of a through dovetail joint made with the use of a specific procedure by a 3-axis CNC machine. This corner joint was used for the simulation of the bending load of the joint in the angle plane – by compression, i.e. by pressing the joint together. The deformation fields, the stress distribution, the stiffness and the bending moment of the joints were evaluated. The finite element system ANSYS was used to create two parametric numerical models of the joint. The first one represents an ideal­ly stiff joint – both joint parts have been glued together. The second model includes the contact between the joined parts. This numerical model was used to monitor the response of the joint stiffness to the change of the static friction coefficient. The results of both models were compared both with each other and with similar analyses conducted within the research into ready-to-assemble furniture joints. The results can be employed in the designing of more complex furniture products with higher demands concerning stiffness characteristics, such as furniture for sitting. However, this assumption depends on the correction of the created parametric models by experimental testing.

  4. Application of D-CRDM Method in Columnar Jointed Basalts Failure Analysis

    Directory of Open Access Journals (Sweden)

    Changyu Jin


    Full Text Available Columnar jointed basalt is a type of joint rock mass formed by the combined cutting effect of original joints and aphanitic microcracks. After excavation unloading, such rock mass manifested distinct mechanical properties including discontinuity, anisotropy, and proneness of cracking. On the basis of former research findings, this paper establishes a D-CRDM method applicable to the analysis of columnar jointed basalt, which not only integrates discrete element and equivalent finite-element methods, but also takes into account the coupling effect of original joints and aphanitic microcracks. From the comparative study of field monitoring data and strain softening constitutive model calculated results, it can be found that this method may well be used for the simulation of mechanical properties of columnar jointed basalts and the determination of rock failure mechanism and failure modes, thus providing references for the selection of supporting measures for this type of rock mass.

  5. Identification of energy dissipation in structural joints by means of the energy flow analysis

    NARCIS (Netherlands)

    Gómez, S.S.; Metrikine, A.; Carboni, B.; Lacarbonara, W.


    In this paper, identification of energy dissipation in the joints of a lab-scale structure is accomplished. The identification is carried out by means of an energy flow analysis and experimental data. The devised procedure enables to formulate an energy balance in the vicinity of the joints to

  6. Women with more severe degrees of temporomandibular disorder exhibit an increase in temperature over the temporomandibular joint


    Dibai-Filho, Almir Vieira; Costa, Ana Cláudia de Souza; Packer, Amanda Carine; de Castro, Ester Moreira; Rodrigues-Bigaton, Delaine


    Aim: The purpose of the present study was to correlate the degree of temporomandibular disorder (TMD) severity and skin temperatures over the temporomandibular joint (TMJ) and masseter and anterior temporalis muscles. Materials and methods: This blind cross-sectional study involved 60 women aged 18–40 years. The volunteers were allocated to groups based on Fonseca anamnestic index (FAI) score: no TMD, mild TMD, moderate TMD, and severe TMD (n = 15 each). All volunteers underwent infrared t...

  7. Heel effects on joint contact force components in the equine digit: a sensitivity analysis. (United States)

    Noble, P; Lejeune, J-P; Caudron, I; Lejeune, P; Collin, B; Denoix, J-M; Serteyn, D


    Whereas the effect of heel configuration on the tension of the suspensory apparatus is well documented in the literature, there are few reports of joint contact force components in the equine distal forelimb. To improve understanding of the effect of heel configuration on equine digit joint loading, a sensitivity analysis was performed to compare the effect of a raised heel on joint contact force components in the coffin and fetlock joints during the stance phase of the trot. Four Warmblood horses were used. An inverse dynamic analysis was carried out using kinematic and kinetic data. Taking into account the tendon wrapping forces (WF) around the sesamoid bones in the calculations, the joint contact forces (CF) were estimated for the coffin and fetlock joints during the trot stance phase (4 m/s). To test the sensitivity of the results to heel configuration changes, calculations were performed repeatedly for different heel configurations (raised by 0, 6 and 12°). A one-way ANOVA with repeated measures was used to test the effect of heel configuration (at the 3 levels) (α = 0.05; P fetlock joint, the peak WF (3.8 ± 0.7 bwt; 4.1 ± 0.3 bwt; 4.4 ± 0.25 bwt) and the peak CF (4.35 ± 0.7 bwt; 4.7 ± 0.35 bwt; 5 ± 0.3 bwt) increased, but not significantly. This analysis suggests that the coffin joint loading and fetlock joint loading are strongly connected. The heel configuration may influence both coffin joint and fetlock joint contact force components. © 2010 EVJ Ltd.

  8. Finite element analysis of a single lap joint


    Heistermann, Christine; Heistermann, Tim; Limam, Marouene; Veljkovic, Milan, ed. lit.


    A single shear lap joint of steel grade S355 is modelled with finite elements to investigate the influence of externally applied tensile loading on the loss of pretension in the engaged bolts. Additionally, a parameter study is performed to understand the effect of various steel grades on the loss of pretension. It is found that the slip resistance of the specimen depends on the steel grade of the clamped plates. Besides, the final resistance of the single shear lap joint has been found to in...

  9. Corrosion behavior in high-temperature pressurized water of Zircaloy-4 joints brazed with Zr-Cu-based amorphous filler alloys (United States)

    Lee, Jung Gu; Lee, Gyoung-Ja; Park, Jin-Ju; Lee, Min-Ku


    The compositional effects of ternary Zr-Cu-X (X: Al, Fe) amorphous filler alloys on galvanic corrosion susceptibility in high-temperature pressurized water were investigated for Zircaloy-4 brazed joints. Through an Al-induced microgalvanic reaction that deteriorated the overall nobility of the joint, application of the Zr-Cu-Al filler alloy caused galvanic coupling to develop readily between the Al-bearing joint and the Al-free base metal, finally leading to massive localized corrosion of the joint. Contrastingly, joints prepared with a Zr-Cu-Fe filler alloy showed excellent corrosion resistance comparable to that of the Zircaloy-4 base metal, since the Cu and Fe elements forming fine intermetallic particles with Zr did not influence the electrochemical stability of the resultant joints. The present results demonstrate that Fe is a more suitable alloying element than Al for brazing filler alloys subjected to high-temperature corrosive environments.

  10. Numerical limit analysis of keyed shear joints in concrete structures

    DEFF Research Database (Denmark)

    Herfelt, Morten Andersen; Poulsen, Peter Noe; Hoang, Linh Cao


    This paper concerns the shear capacity of keyed joints, which are transversely reinforced with overlapping U-bar loops. It is known from experimental studies that the discontinuity of the transverse reinforcement affects the capacity as well as the failure mode; however, to the best knowledge of ...

  11. Biomechanical analysis of rheumatoid arthritis of the wrist joint. (United States)

    Bajuri, M N; Kadir, Mohammed Rafiq Abdul; Amin, Iskandar M; Ochsner, Andreas


    The wrist is the most complex joint for virtual three-dimensional simulations, and the complexity is even more pronounced when dealing with skeletal disorders of the joint such, as rheumatoid arthritis (RA). In order to analyse the biomechanical difference between healthy and diseased joints, three-dimensional models of these two wrist conditions were developed from computed tomography images. These images consist of eight carpal bones, five metacarpal bones, the distal radius and ulna. The cartilages were developed based on the shape of the available articulations and ligaments were simulated via mechanical links. The RA model was developed accurately by simulating all ten common criteria of the disease related to the wrist. Results from the finite element (FE) analyses showed that the RA model produced three times higher contact pressure at the articulations compared to the healthy model. Normal physiological load transfer also changed from predominantly through the radial side to an increased load transfer approximately 5% towards the ulnar. Based on an extensive literature search, this is the first ever reported work that simulates the pathological conditions of the rheumatoid arthritis of the wrist joint.

  12. Manpower Management for Joint Specialty Officers: A Comparative Analysis (United States)


    Average 44 6 4 - - - Obeanography Joint Staff 0 - -. Jont slpaaY 0 0 -. Servl HQ$ 0 0 -oo . . . Other Jolt - 0 -. . . Service Average 55 3 . PuNk ...Planning Activity 1 US Atlantic Command (USLANTCOM) 8 US Caentraj Command (USCtNTOOM) 11 US European Command (USEUCOM) 14 US Paciftc Command (USPACOM) 21 US

  13. Controlling the joint local false discovery rate is more powerful than meta-analysis methods in joint analysis of summary statistics from multiple genome-wide association studies. (United States)

    Jiang, Wei; Yu, Weichuan


    In genome-wide association studies (GWASs) of common diseases/traits, we often analyze multiple GWASs with the same phenotype together to discover associated genetic variants with higher power. Since it is difficult to access data with detailed individual measurements, summary-statistics-based meta-analysis methods have become popular to jointly analyze datasets from multiple GWASs. In this paper, we propose a novel summary-statistics-based joint analysis method based on controlling the joint local false discovery rate (Jlfdr). We prove that our method is the most powerful summary-statistics-based joint analysis method when controlling the false discovery rate at a certain level. In particular, the Jlfdr-based method achieves higher power than commonly used meta-analysis methods when analyzing heterogeneous datasets from multiple GWASs. Simulation experiments demonstrate the superior power of our method over meta-analysis methods. Also, our method discovers more associations than meta-analysis methods from empirical datasets of four phenotypes. The R-package is available at: . Supplementary data are available at Bioinformatics online.

  14. Design of Experiment and Analysis for the Joint Dynamic Allocation of Fires and Sensors (JDAFS) Simulation

    National Research Council Canada - National Science Library

    Freye, Jeffrey T


    ...) model, a low-resolution, Discrete Event Simulation Model with embedded optimization enables the analysis of many scenarios and factors to explore Joint Intelligence, Surveillance, and Reconnaissance (ISR) missions...

  15. High conductivity composite flip-chip joints and silver-indium bonding to bismuth telluride for high temperature applications (United States)

    Lin, Wen P.

    Two projects are reported. First, the barrier layer and silver (Ag)-indium (In) transient liquid phase (TLP) bonding for thermoelectric (TE) modules at high temperature were studied, and followed with a survey of Ag microstructure and grain growth kinetics. Second, the high electrical conductivity joint materials bonded by both Ag-AgIn TLP and solid-state bonding processes for small size flip-chip applications were designed. In the first project, barrier and Ag-In TLP bonding layer for TE module at high temperature application were studied. Bismuth telluride (Bi2 Te3) and its alloys are used as materials for a TE module. A barrier/bonding composite was developed to satisfy the TE module for high temperature operation. Titanium (Ti)/ gold (Au) was chosen as the barrier layers and an Ag-rich Ag-In joint was chosen as the bonding layer. An electron-beam evaporated Ti layer was selected as the barrier layer. An Ag-In fluxless TLP bonding process was developed to bond the Bi 2Te3 chips to the alumina substrates for high temperature applications. To prepare for bonding, the Bi2Te3 chips were coated with a Ti/Au barrier layer followed by a Ag layer. The alumina substrates with titanium-tungsten (TiW)/Au were then electroplated with the Ag/In/Ag structure. These Bi2Te3 chips were bonded to alumina substrates at a bonding temperature of 180ºC with a static pressure as low as 100psi. The resulting void-free joint consists of five regions: Ag, (Ag), Ag2In, (Ag), and Ag, where (Ag) is Ag-rich solid solution with In atoms in it and Ag is pure Ag. This joint has a melting temperature higher than 660ºC, and it manages the coefficient of thermal expansion (CTE) mismatch between the Bi2Te3 and alumina substrate. The whole Ti/Au barrier layer and Ag-In bonding composite between Bi 2Te3 and alumina survived after an aging test at 250°C for 200 hours. The Ag-In joint transformed from Ag/(Ag)/Ag2In/(Ag)/Ag to a more reliable (Ag) rich layer after the aging test. Ag thin films were

  16. Influence of solder joint length to the mechanical aspect during the thermal stress analysis (United States)

    Tan, J. S.; Khor, C. Y.; Rahim, Wan Mohd Faizal Wan Abd; Ishak, Muhammad Ikman; Rosli, M. U.; Jamalludin, Mohd Riduan; Zakaria, M. S.; Nawi, M. A. M.; Aziz, M. S. Abdul; Ani, F. Che


    Solder joint is an important interconnector in surface mount technology (SMT) assembly process. The real time stress, strain and displacement of the solder joint is difficult to observe and assess the experiment. To tackle these problems, simulation analysis was employed to study the von Mises stress, strain and displacement in the thermal stress analysis by using Finite element based software. In this study, a model of leadless electronic package was considered. The thermal stress analysis was performed to investigate the effect of the solder length to those mechanical aspects. The simulation results revealed that solder length gives significant effect to the maximum von Mises stress to the solder joint. Besides, changes in solder length also influence the displacement of the solder joint in the thermal environment. The increment of the solder length significantly reduces the von Mises stress and strain on the solder joint. Thus, the understanding of the physical parameter for solder joint is important for engineer prior to designing the solder joint of the electronic component.

  17. Joint angle estimation with accelerometers for dynamic postural analysis. (United States)

    Ma, Jianting; Kharboutly, Haissam; Benali, Abderraouf; Benamar, Faïz; Bouzit, Mourad


    This paper presents a new accelerometer based method for estimating the posture of a subject standing on a dynamic perturbation platform. The induced perturbation is used to study the control mechanisms as well as the balance requirements that regulate the upright standing. These perturbations are translated into different intensity levels of speed and acceleration along longitudinal and lateral directions of motion. In our method, the human posture is modeled by a tridimensional, three-segment inverted pendulum which simultaneously takes into account both the anterior-posterior and medio-lateral strategies of hip and ankle. Four tri-axial accelerometers are used her, one accelerometer is placed on the platform, and the other three are attached to a human subject. Based on the results, the joint angle estimated compare closely to measurements from magnetic encoders placed on an articulated arm joint. The results were also comparable to those found when using a high-end optical motion capture system coupled with advanced biomechanical simulation software. This paper presents the comparisons of our accelerometer-based method with encoder and optical marker based method of the estimated joint angles under different dynamics perturbations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Analysis of synovial fluid of the Capybara's stifle joints. (United States)

    Brombini, Giovanna C; Rahal, Sheila C; Bergamini, Bruno C S; Lopes, Raimundo S; Santos, Ivan F C; Schimming, Bruno C


    Although normal synovial fluid has been well characterized in domestic animals such as dogs, cats, horses, and cows, the available information on larger rodents is scarce. The purpose of the study was to analyze the physical, chemical, and cytologic characteristics of the synovial fluid in stifle joints of Capybaras. Five free-ranging adult female Capybaras (Hydrochoerus hydrochaeris), weighing from 37 to 56 kg were used. Synovial fluid was obtained by aspiration of 10 stifle joints. Samples were analyzed for physical, chemical, and cytologic properties. Spontaneous clotting was negative in 9 samples. Most synovial fluids had pH 8, and protein concentrations ranged from 1.6 to 3.6 g/dL. The mucin clot test was good in all 6 samples that were tested. Nucleated cell counts ranged from 140 to 508 cells/μL. Relative differential leukocyte counts demonstrated a predominance of mononuclear cells (97.6%), including 76.2% undifferentiated mononuclear cells, 18.1% macrophages, and 3.66% lymphocytes. Polymorphonuclear cells included 1.83% neutrophils and 0.2% eosinophils. The synovial stifle joint fluid of healthy free-ranging adult Capybaras is clear, colorless, viscous, and with chemical features and cytologic findings similar to those seen in domestic animals. © 2017 American Society for Veterinary Clinical Pathology.

  19. A multivariate partial least squares approach to joint association analysis for multiple correlated traits

    Directory of Open Access Journals (Sweden)

    Yang Xu


    Full Text Available Many complex traits are highly correlated rather than independent. By taking the correlation structure of multiple traits into account, joint association analyses can achieve both higher statistical power and more accurate estimation. To develop a statistical approach to joint association analysis that includes allele detection and genetic effect estimation, we combined multivariate partial least squares regression with variable selection strategies and selected the optimal model using the Bayesian Information Criterion (BIC. We then performed extensive simulations under varying heritabilities and sample sizes to compare the performance achieved using our method with those obtained by single-trait multilocus methods. Joint association analysis has measurable advantages over single-trait methods, as it exhibits superior gene detection power, especially for pleiotropic genes. Sample size, heritability, polymorphic information content (PIC, and magnitude of gene effects influence the statistical power, accuracy and precision of effect estimation by the joint association analysis.

  20. Load environment of rail joint bars -- phase II, joint bar service environment and fatigue analysis. (United States)


    Detailed analysis of measured bending strains shows that the foundation deflections have the most significant effect on the : magnitude of strains. All other factors, such as track type, track geometry, and fastening systems, have a less significant ...

  1. Numerical analysis of weld pool for galvanized steel with lap joint in GTAW

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hunchul; Park, Kyungbae; Kim, Yougjun; Cho, Jungho [Chungbuk National University, Cheongju (Korea, Republic of); Kim, Dong-Yoon; Kang, Moon-Jin [Korea Institute of Industrial Technology, Incheon (Korea, Republic of)


    Galvanized steel is widely used and its demand is growing in automotive industry due to high quality requirement for corrosion resistance. Although there are a lot of demands on using galvanized steel as automotive parts especially for outer body, it has a grave flaw in its welding process. The difficulty is low weldability due to various defects such as porosities and blow holes in weldment, which occurred during welding. A solution to prevent these defects is using hybrid welding process, with two more welding processes. One of the hybrid solutions is using Gas tungsten arc welding (GTAW) as leading position in order to remove the zinc (Zn) coating on the surface before the followed practical fusion welding process. In this research, a numerical analysis model which can predict the eliminated Zn coated layers and the area of Fusion zone (FZ). Developed numerical analysis model was validated through comparing experiment to simulation. Basically, arc heat flux, arc pressure, electromagnetic force and Marangoni flow were employed as the boundary conditions and body force terms. Governing equations such as the continuity, momentum, Volume of fluid (VOF) and energy equations were adopted as usual. In addition to previous model, concentrated arc heat flux and contact thermal conductance models are newly suggested and showed successful result. They are adopted to realize edge concentrated arc and interfacial thermal conductance in lap joint fillet arc welding. Developed numerical analysis model successfully simulated the weld pool and temperature profile therefore the predicted Zn removed area considerably coincided with experimental result.

  2. The Analysis of Welding Conditions Under the Flux of Double-Sides Joints Without Edge Preparation (United States)

    Sidorov, Vladimir P.


    This paper represents the results of analysis for automatic welding conditions under the flux of double-sides butt joint without edge preparation. As the process characteristics, a specific energy of welding, joint formation rate, average weld width, fusion rate of base metal and other parameters were used. It is determined an optimal joint rate of about 1 cm2/s, that can be used to calculate welding conditions. The paper founds the use of linear dependence between specific energy of welding and cross-section area of base metal’s fusion.

  3. [Analysis of development of hip joint dysplasia in dogs]. (United States)

    Ledecký, V; Sevcík, A; Capík, I; Trbolová, A


    Hip joint dysplasia in dogs occurs mainly in large and heavy breeds. It brings about changes on the acetabulum (socket) and the head of thigh bone, thus causing pain, tiredness, refusal to jump and refusal of increased activity. Even though presently the genetic basis of development of this disease, numerous literary sources indicate existence of pre-disposing factors that facilitate development in later stages of life. Diet and unbalanced development of skeleton and support tissues-ligaments, joint capsule and musculature also have the effect on development of dysplasia. We have analyzed acquired results of X-ray examination of dogs-German shepherds. The size of the group was 4 206 and the examination was aimed at incidence of hip-joint dysplasia during the period of 1977-1995 in the Slovak Republic. We have found out that in 1977 there were 70.7% positive cases out of the total number of examined individuals. Gradual exclusion of dogs with heavier grades of dysplasia (D, E) decreased occurrence of dysplasia to current rate of 40.8%. We considered it to be a high incidence rate. Internal structure of the positive group has changed. The number of dogs with the lightest grade of dysplasia (B) has increased, while the number of heavier grade dysplasia (C, D, E) decreased. In other breeds of dogs, of which more than 20 have been examined at the clinic, the following results have been acquired: Slovak chuvash-32%, Bavarian and Hannover bloodhound-30.6%, Rotweiler-28.6%, Newfoundland dog-26.3%, Bern sheep-dog-13.6%. At the same time we analyze the incidence of dysplasia in dogs whose parents were negative. Group of descendants of 11 negative males and 28 females consisted of 73 dogs. Through x-ray examination, 42.5% of dogs were found to have dysplasia B, C and D at the age of 1 year.

  4. Finite element analysis of thumb carpometacarpal joint implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.


    The thumb carpometacarpal joint is frequently replaced in women who have developed severe osteoarthritis of the hand. A new, privately developed implant design consists of two components, trapezial and metacarpal, each with a saddle-shaped articulating surface. A three dimensional finite element model of this implant has been developed to analyze stresses on the device. The first simulations using the model involve loading the implant with forces normal to the trapezial component. Preliminary results show contact stress distributions at the particulating surfaces of the implant.

  5. Women with more severe degrees of temporomandibular disorder exhibit an increase in temperature over the temporomandibular joint. (United States)

    Dibai-Filho, Almir Vieira; Costa, Ana Cláudia de Souza; Packer, Amanda Carine; de Castro, Ester Moreira; Rodrigues-Bigaton, Delaine


    The purpose of the present study was to correlate the degree of temporomandibular disorder (TMD) severity and skin temperatures over the temporomandibular joint (TMJ) and masseter and anterior temporalis muscles. This blind cross-sectional study involved 60 women aged 18-40 years. The volunteers were allocated to groups based on Fonseca anamnestic index (FAI) score: no TMD, mild TMD, moderate TMD, and severe TMD (n = 15 each). All volunteers underwent infrared thermography for the determination of skin temperatures over the TMJ, masseter and anterior temporalis muscles. The Shapiro-Wilk test was used to determine the normality of the data. The Kruskal-Wallis test, followed by Dunn's test, was used for comparisons among groups according to TMD severity. Spearman's correlation coefficients were calculated to determine the strength of associations among variables. Weak, positive, significant associations were found between FAI score and skin temperatures over the left TMJ (rs = 0.195, p = 0.009) and right TMJ (rs = 0.238, p = 0.001). Temperatures over the right and left TMJ were significantly higher in groups with more severe TMD (p < 0.05). FAI score was associated with skin temperature over the TMJ, as determined by infrared thermography, in this sample. Women with more severe TMD demonstrated a bilateral increase in skin temperature.

  6. Application of Abaqus to analysis of the temperature field in elements heated by moving heat sources

    Directory of Open Access Journals (Sweden)

    W. Piekarska


    Full Text Available Numerical analysis of thermal phenomena occurring during laser beam heating is presented in this paper. Numerical models of surface andvolumetric heat sources were presented and the influence of different laser beam heat source power distribution on temperature field wasanalyzed. Temperature field was obtained by a numerical solution the transient heat transfer equation with activity of inner heat sources using finite element method. Temperature distribution analysis in welded joint was performed in the ABAQUS/Standard solver. The DFLUXsubroutine was used for implementation of the movable welding heat source model. Temperature-depended thermophysical properties for steelwere assumed in computer simulations. Temperature distribution in laser beam surface heated and butt welded plates was numericallyestimated.

  7. Joint Utility of Event-Dependent and Environmental Crime Analysis Techniques for Violent Crime Forecasting (United States)

    Caplan, Joel M.; Kennedy, Leslie W.; Piza, Eric L.


    Violent crime incidents occurring in Irvington, New Jersey, in 2007 and 2008 are used to assess the joint analytical capabilities of point pattern analysis, hotspot mapping, near-repeat analysis, and risk terrain modeling. One approach to crime analysis suggests that the best way to predict future crime occurrence is to use past behavior, such as…

  8. Development of Be/Glidcop joint obtained by hot isostatic pressing diffusion bonding for high in-service temperature

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Antonin, F.; Bucci, P.; Burlet, H.; Le Marois, G. [CEA Centre d`Etudes de Grenoble, 38 (France); Barberi, D.; Laille, A.


    This paper addresses some aspects of the beryllium-Glidcop joining by Hot Isostatic Pressing diffusion Bonding. The quality of a joint is mainly dependent on the interface microstructure. Thus, as Be/copper direct bonding is not recommended, the choice of interlayers is a critical point. The joining process parameters, i.e. temperature, pressure and time, must take into account the in-service requirements, the mechanical and metallurgical properties of each material. The Be/Glidcop joining process developed at CEA/Grenoble is presented here. (author)

  9. Select aspects of FEM analysis for bonded joints of polymer composite materials (United States)

    Rudawska, A.


    The paper presents selected aspects of modelling bonded joints of polymer composite materials by finite element method. The shear-loaded adhesive lap joints made of epoxy-graphite and epoxy-glass composite materials were investigated. The research objective was to determine correct modelling of adhesive layers using cohesive elements and of bonded joints for selected epoxy composite materials with different mechanical properties (e.g. Young's modulus) and geometrical dimensions, using, however, the same type of adhesive. The numerical analysis was performed based on experimental tests. A comparison is made between the distribution of reduced stress in the examined joint models according to the H-M- H hypothesis and that determined according to the maximum principal stress hypothesis. The finite elements analysis was performed in ABAQUS software and the traction-separation failure criterion was used for the damage onset and growth in the adhesive layer.

  10. Magnetization of the joint-free high temperature superconductor (RE)Ba2Cu3Ox coil by field cooling (United States)

    Zheng, Yali; Wang, Yawei; Li, Jianwei; Jin, Zhijian


    Joint-free (RE)Ba2Cu3Ox (REBCO) coil based on `wind-and-flip' technique has been developed to generate a persistent magnetic field without power supply. This paper is to study the magnetization characteristics of the joint-free REBCO coil by field cooling, in order to trap higher field. A joint-free pancake coil is wound by REBCO tapes and the field cooling magnetization test is performed on it. An approximate numerical model based on H-formulation is built for this coil to analyze its magnetization behavior, which is validated by the experimental results Analysis show that a persistent direct current is induced in the coil during the field cooling operation, which generates the trapped field. The induced current of the joint-free coil shows an intrinsic non-uniform distribution among turns. Increasing the magnetization field and critical current of REBCO conductors can considerably increase the trapped field. But the trapping factor (the rate of trapped field to background magnetization field) reaches a maximum value (60 % for the test coil). This maximum value is an intrinsic characteristics for a fabricated coil, which only depends on the coil's geometry structure. With a same usage of REBCO tapes, the trapping factor can be improved significantly by optimizing the coil structure to multiple pancakes, and it can approach 100 %.

  11. Magnetization of the joint-free high temperature superconductor (REBa2Cu3Ox coil by field cooling

    Directory of Open Access Journals (Sweden)

    Yali Zheng


    Full Text Available Joint-free (REBa2Cu3Ox (REBCO coil based on ‘wind-and-flip’ technique has been developed to generate a persistent magnetic field without power supply. This paper is to study the magnetization characteristics of the joint-free REBCO coil by field cooling, in order to trap higher field. A joint-free pancake coil is wound by REBCO tapes and the field cooling magnetization test is performed on it. An approximate numerical model based on H-formulation is built for this coil to analyze its magnetization behavior, which is validated by the experimental results Analysis show that a persistent direct current is induced in the coil during the field cooling operation, which generates the trapped field. The induced current of the joint-free coil shows an intrinsic non-uniform distribution among turns. Increasing the magnetization field and critical current of REBCO conductors can considerably increase the trapped field. But the trapping factor (the rate of trapped field to background magnetization field reaches a maximum value (60 % for the test coil. This maximum value is an intrinsic characteristics for a fabricated coil, which only depends on the coil’s geometry structure. With a same usage of REBCO tapes, the trapping factor can be improved significantly by optimizing the coil structure to multiple pancakes, and it can approach 100 %.

  12. Stress Analysis of Adhesive Lap Joint of Hollow Shafts Subjected to Torsional Moments


    仲野, 雄一; 高城, 有希久


    The stress and strain distributions in adhesively bonded lap joints of dissimilar hollow shafts are examined using the axisymmetric theory of elasticity. In the analysis, the joint is modeled as an elastic three-body contact problem where the hollow shafts and the adhesive are replaced by finite hollow cylinders. The effects of the ratio of Young's modulus of the adhesive to that of the shaft, the overlap length and the thickness of the adhesive on the stress distributions at the interfaces i...

  13. Soft Smart Garments for Lower Limb Joint Position Analysis

    Directory of Open Access Journals (Sweden)

    Massimo Totaro


    Full Text Available Revealing human movement requires lightweight, flexible systems capable of detecting mechanical parameters (like strain and pressure while being worn comfortably by the user, and not interfering with his/her activity. In this work we address such multifaceted challenge with the development of smart garments for lower limb motion detection, like a textile kneepad and anklet in which soft sensors and readout electronics are embedded for retrieving movement of the specific joint. Stretchable capacitive sensors with a three-electrode configuration are built combining conductive textiles and elastomeric layers, and distributed around knee and ankle. Results show an excellent behavior in the ~30% strain range, hence the correlation between sensors’ responses and the optically tracked Euler angles is allowed for basic lower limb movements. Bending during knee flexion/extension is detected, and it is discriminated from any external contact by implementing in real time a low computational algorithm. The smart anklet is designed to address joint motion detection in and off the sagittal plane. Ankle dorsi/plantar flexion, adduction/abduction, and rotation are retrieved. Both knee and ankle smart garments show a high accuracy in movement detection, with a RMSE less than 4° in the worst case.

  14. Soft Smart Garments for Lower Limb Joint Position Analysis. (United States)

    Totaro, Massimo; Poliero, Tommaso; Mondini, Alessio; Lucarotti, Chiara; Cairoli, Giovanni; Ortiz, Jesùs; Beccai, Lucia


    Revealing human movement requires lightweight, flexible systems capable of detecting mechanical parameters (like strain and pressure) while being worn comfortably by the user, and not interfering with his/her activity. In this work we address such multifaceted challenge with the development of smart garments for lower limb motion detection, like a textile kneepad and anklet in which soft sensors and readout electronics are embedded for retrieving movement of the specific joint. Stretchable capacitive sensors with a three-electrode configuration are built combining conductive textiles and elastomeric layers, and distributed around knee and ankle. Results show an excellent behavior in the ~30% strain range, hence the correlation between sensors' responses and the optically tracked Euler angles is allowed for basic lower limb movements. Bending during knee flexion/extension is detected, and it is discriminated from any external contact by implementing in real time a low computational algorithm. The smart anklet is designed to address joint motion detection in and off the sagittal plane. Ankle dorsi/plantar flexion, adduction/abduction, and rotation are retrieved. Both knee and ankle smart garments show a high accuracy in movement detection, with a RMSE less than 4° in the worst case.

  15. Comparative Modal Analysis of Gasketed and Nongasketed Bolted Flanged Pipe Joints: FEA Approach

    Directory of Open Access Journals (Sweden)

    Muhammad Abid


    Full Text Available It is widely known that resonance can quickly lead to failure in vibrating bolted flanged pipe joints. Condition monitoring is performed time to time in some industries for smooth operation of a system, whereas mostly trial-and-error tests are performed to control vibration. During all this process, the inherent design problems are not considered. A bolted flange joint in piping system is not a simple problem, being the combination of flange, gasket, bolts, and washers. The success of a bolted flanged pipe joint is defined by the “static mode of load” in the joint. However, it has been recognized that a “dynamic mode of load” governs in a gasketed bolted flanged pipe joint, which leads to its failure due to flange rotation, providing flange yielding, fatigue of bolts, and gasket crushing. This paper presents results of detailed 3D finite element and mathematical modal analysis under bolt up to determine natural frequencies and mode shapes of gasketed flanged joints with and without raised face in comparison to the nongasketed flange joint.

  16. Joint small-angle X-ray and neutron scattering data analysis of asymmetric lipid vesicles. (United States)

    Eicher, Barbara; Heberle, Frederick A; Marquardt, Drew; Rechberger, Gerald N; Katsaras, John; Pabst, Georg


    Low- and high-resolution models describing the internal transbilayer structure of asymmetric lipid vesicles have been developed. These models can be used for the joint analysis of small-angle neutron and X-ray scattering data. The models describe the underlying scattering length density/electron density profiles either in terms of slabs or through the so-called scattering density profile, previously applied to symmetric lipid vesicles. Both models yield structural details of asymmetric membranes, such as the individual area per lipid, and the hydrocarbon thickness of the inner and outer bilayer leaflets. The scattering density profile model, however, comes at a cost of increased computational effort but results in greater structural resolution, showing a slightly lower packing of lipids in the outer bilayer leaflet of ∼120 nm diameter palmitoyl-oleoyl phosphatidyl-choline (POPC) vesicles, compared to the inner leaflet. Analysis of asymmetric dipalmitoyl phosphatidylcholine/POPC vesicles did not reveal evidence of transbilayer coupling between the inner and outer leaflets at 323 K, i.e. above the melting transition temperature of the two lipids.

  17. Progressive Failure Analysis of Adhesive Joints of Filament-Wound Composite Pressure Vessel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Junhwan; Shin, Kwangbok [Hanbat National University, Daejeon (Korea, Republic of); Hwang, Taekyung [Agency for Defence Development, Daejeon (Korea, Republic of)


    This study performed the progressive failure analysis of adhesive joints of a composite pressure vessel with a separated dome by using a cohesive zone model. In order to determine the input parameters of a cohesive element for numerical analysis, the interlaminar fracture toughness values in modes I and II and in the mixed mode for the adhesive joints of the composite pressure vessel were obtained by a material test. All specimens were manufactured by the filament winding method. A mechanical test was performed on adhesively bonded double-lap joints to determine the shear strength of the adhesive joints and verify the reliability of the cohesive zone model for progressive failure analysis. The test results showed that the shear strength of the adhesive joints was 32MPa; the experiment and analysis results had an error of about 4.4%, indicating their relatively good agreement. The progressive failure analysis of a composite pressure vessel with an adhesively bonded dome performed using the cohesive zone model showed that only 5.8% of the total adhesive length was debonded and this debonded length did not affect the structural integrity of the vessel.

  18. Experiments and kinematics analysis of a hand rehabilitation exoskeleton with circuitous joints. (United States)

    Zhang, Fuhai; Fu, Yili; Zhang, Qinchao; Wang, Shuguo


    Aiming at the hand rehabilitation of stroke patients, a wearable hand exoskeleton with circuitous joint is proposed. The circuitous joint adopts the symmetric pinion and rack mechanism (SPRM) with the parallel mechanism. The exoskeleton finger is a serial mechanism composed of three closed-chain SPRM joints in series. The kinematic equations of the open chain of the finger and the closed chains of the SPRM joints were built to analyze the kinematics of the hand rehabilitation exoskeleton. The experimental setup of the hand rehabilitation exoskeleton was built and the continuous passive motion (CPM) rehabilitation experiment and the test of human-robot interaction force measurement were conducted. Experiment results show that the mechanical design of the hand rehabilitation robot is reasonable and that the kinematic analysis is correct, thus the exoskeleton can be used for the hand rehabilitation of stroke patients.

  19. Re-analysis of fatigue data for welded joints using the notch stress approach

    DEFF Research Database (Denmark)

    Pedersen, Mikkel Melters; Mouritsen, Ole Ø.; Hansen, Michael Rygaard


    Experimental fatigue data for welded joints have been collected and subjected to re-analysis using the notch stress approach according to IIW recommendations. This leads to an overview regarding the reliability of the approach, based on a large number of results (767 specimens). Evidently......, there are some limitations in the approach regarding mild notch joints, such as butt joints, which can be assessed non-conservatively. In order to alleviate this problem, an increased minimum notch factor of Kw>2.0 is suggested instead of the current recommendation of Kw>1.6. The data for most fillet......-welded joints agree quite well with the FAT 225 curve; however a reduction to FAT 200 is suggested in order to achieve approximately the same safety as observed in the nominal stress approach....

  20. Gradient material model in analysis of mechanical joints of CFRP laminate (United States)

    Puchała, Krzysztof; ElŻbieta, Szymczyk; Jachimowicz, Jerzy; Bogusz, Paweł


    Mechanical joints (e.g. bolted) used for decades are proved to be reliable. They can be assembled and applied in very rough conditions since they are less sensitive to environmental effects than other types of joints (e.g. adhesive). Therefore, they are still employed in aircraft design. High specific stiffness and strength of composite materials (especially CFRP) cause a continuous increase in their usage in aircraft structures. In general, composites are brittle materials and more notch sensitive than metal alloys. Hole making is a necessary stage in manufacturing of a mechanical joint. Holes vicinities are the areas of high stress concentrations and determine load capability of the whole structure. Therefore, mechanical joints of composite parts require a special focus during both a designing and a manufacturing process. The aim of the paper is analysis of potential local material weakness/deterioration caused by a drilling process and its influence on the global response of a mechanical joint. The specimen in the form of a double-shear joint was analyzed. The weakened areas were identified on the basis of NDT ultrasonic analysis. A simple gradient material model was proposed to describe the hole vicinity. Numerical simulations were performed and compared to experimental results.

  1. Analysis of controlling parameters for shear behavior of rock joints with FLAC3D (United States)

    Tiwari, Prasoon

    The research investigation is conducted to perform an analysis of sensitivity of parameters affecting the strength of joints in rock mass. Friction angle, normal stiffness, shear stiffness and shear displacement are the parameters analyzed with respect to shear strength of rock joints. Discontinuities have an important influence on the deformational behavior of rock systems; hence, proper consideration of the physical and mechanical properties of discontinuities is necessary during experimental investigation, in order to correctly evaluate the shear behavior. These parameters are utilized to simulate the in situ stress condition in numerical modeling, which is important for safe and economical design of various engineering constructions. These concerns require accurate quantification of shear strength of unfilled and in-filled joints, proper understanding of the basic mechanics of discontinuity and the principals involved in their shear deformation. This can be achieved through laboratory testing on natural rock core samples. In the present work, the detailed account of test results of direct shear tests performed on rock joints is presented. Rock samples are obtained by core drilling in an underground mine, in Nevada. These rock samples, containing joint, are used to perform direct shear strength test. Calibration of numerical model is done on average values obtained from direct shear strength test. Analysis of sensitivity of parameters effecting shear strength of rock is done in FLAC3D shear test environment. A numerical parametric study is done, according to the Mohr-Coulomb constitutive model, and results obtained are plotted to estimate performance of rock joints.

  2. The reliability of the repair weld joints of aged high temperature components in fossil power boilers

    Energy Technology Data Exchange (ETDEWEB)

    Okamura, Hiroyuki [Science Univ. of Tokyo (Japan); Ohtani, Ryuichi [Kyoto Univ. (Japan); Fujii, Kazuya [Japan Power Engineering and Inspection Corp., Tokyo (Japan); Yokoyama, Tomomitsu; Nishimura, Nobuhiko [Mitsubishi Heavy Industries Ltd., Tokyo (Japan); Suzuki, Komei [Japan Steel Works Ltd., Tokyo (Japan)


    It is of fundamental engineering importance to be able to give reliable assessments of the effective service life of the critical components used within fossil power plants, particularly for those operating for prolonged periods. It is common practice for such assessments to have been estimated using destructive tests, typically the stress rupture test, this having been recognized as one of the most reliable evaluation methods available. Its only drawback is that it often does not permit the component to be in use following the sampling of the test specimen without repairing. The current piece of work focuses on the reliability of the repair welds of components for specimens taken from fossil power plants, having been in service for prolonged periods. Several such repairs to welds have been made to an old power boiler, in particular to a superheater header which is fabricated from 2.25Cr-1Mo steel. Under close examination the repairs to the girth weldment showed susceptibilities of weld cracking, similar to that observed in as-manufactured material. Within the repaired region of the welded joint the microstructure, tensile properties and toughness seemed to be unaffected. The hardness attained its minimum value within the heat affected zone, HAZ of the repair weld, overlapping that of original girth weld HAZ. Furthermore, the stress rupture strength achieved its minimum value at the same position taking on the same value as the strength associated with the aged girth welded joint. (orig.)

  3. Outcomes Following Acute Metacarpophalangeal Joint Arthroplasty Dislocation: An Analysis of 37 Cases. (United States)

    Wanderman, Nathan; Wagner, Eric; Moran, Steven; Rizzo, Marco


    There remains a paucity of information regarding the treatment outcomes of dislocation after metacarpophalangeal (MCP) joint arthroplasty. The purpose of this study was to assess the outcomes of surgical and nonsurgical treatment modalities of MCP arthroplasty dislocations. Of 816 MCP joint arthroplasties over a 14-year period, there were 37 (4%) acute MCP joint dislocations that required intervention by a health care professional. Implants involved included 28 nonconstrained implants including pyrocarbon (n = 17) and surface replacement arthroplasty (n = 11), and 9 silicone implants. The analysis included the treatment of dislocations after primary (n = 30) and revision (n = 7) MCP joint arthroplasty. Dislocation was defined as clinical and radiographic evidence of MCP joint prosthetic acute dislocation diagnosed and treated by a fellowship trained hand surgeon. Etiologies underlying the dislocations included implant fracture (n = 6), component loosening (n = 2), and soft tissue deficiency (n = 29). Of the 37 dislocations, treatments included 14 nonsurgical (closed reduction, orthosis fabrication) all of which ultimately failed. Surgically, including some of the failed prior procedures, 18 soft tissue stabilization procedures and 21 revision arthroplasties were performed, with 6 that had failed soft tissue stabilization. The soft tissue stabilization procedures had a 28% success rate in achieving a stable MCP joint. Revision arthroplasty had a 71% success rate. Subgroup analysis showed an 86% success rate for silicone revisions and a 43% success rate with nonconstrained revisions, with 80% and 36% 5-year survival free of instability, for the 2 types of implants, respectively. The treatment of MCP joint arthroplasty dislocation with revision to silicone implant appears to hold the most promise in achieving a stable MCP joint after an acute prosthetic dislocation. Therapeutic IV. Copyright © 2017 American Society for Surgery of the Hand. Published by

  4. Joint Analysis of Binomial and Continuous Traits with a Recursive Model

    DEFF Research Database (Denmark)

    Varona, Louis; Sorensen, Daniel


    This work presents a model for the joint analysis of a binomial and a Gaussian trait using a recursive parametrization that leads to a computationally efficient implementation. The model is illustrated in an analysis of mortality and litter size in two breeds of Danish pigs, Landrace and Yorkshir...

  5. A fracture mechanics analysis of adhesive failure in a single lap shear joint. (United States)

    Devries, K. L.; Williams, M. L.; Chang, M. D.


    Discussion of adhesive fracture of single lap shear joints in terms of a maximum stress criterion and an energy balance. The Goland and Reissner (1944) analysis is used to determine the stress distribution in the adhesive assembly, and the results obtained are introduced into an energy balance to determine the initiation of adhesive fracture. In the stress analysis the loads at the edges of the joint are first determined. This is a problem in which the deformation of the joint sheets must be taken into account and is solved by using the finite-deflection theory of cylindrically bent plates. Then the stress in the joint due to applied loads is determined. This problem is formulated as one in plane strain consisting of two rectangular sheets of equal thickness and unit width. With the aid of this stress analysis and the stresses obtained from the conditions of equilibrium the contributions to the energy change with crack length are calculated. The analysis performed is then compared with a maximum stress criterion for a lap joint.

  6. Joint analysis of epistemic and aleatory uncertainty in stability analysis for geo-hazard assessments (United States)

    Rohmer, Jeremy; Verdel, Thierry


    .g., Baudrit et al., 2007) for geo-hazard assessments. A graphical tool is then developed to explore: 1. the contribution of both types of uncertainty, aleatoric and epistemic; 2. the regions of the imprecise or random parameters which contribute the most to the imprecision on the failure probability P. The method is applied on two case studies (a mine pillar and a steep slope stability analysis, Rohmer and Verdel, 2014) to investigate the necessity for extra data acquisition on parameters whose imprecision can hardly be modelled by probabilities due to the scarcity of the available information (respectively the extraction ratio and the cliff geometry). References Baudrit, C., Couso, I., & Dubois, D. (2007). Joint propagation of probability and possibility in risk analysis: Towards a formal framework. International Journal of Approximate Reasoning, 45(1), 82-105. Rohmer, J., & Verdel, T. (2014). Joint exploration of regional importance of possibilistic and probabilistic uncertainty in stability analysis. Computers and Geotechnics, 61, 308-315.

  7. Sensitivity Analysis for Residual Stress on DVI (Direct Vessel Injection) Nozzle Welded Joint

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Byeong Wook; Chung, Sung Ho; Lee, Jung Hun; Kim, Oak Sug [DOOSAN Heavy Industries and Construction Co. LTD, Reactor Design Team, 555 Guygok-dong Changwon (Korea, Republic of)


    Generally, any welding process produces high compressive or tensile residual stresses in the heat affected zone depending on the method, shape and procedures of the weldment. In particular, the tensile residual stresses have a considerable effect on the material strength, fatigue strength and corrosion cracking. For this reason, it is important that some knowledge of the internal stress state be deduced either from measurements or from modeling predictions. In this study, the residual stresses after a multi-pass welding process for DVI nozzle welding joint were evaluated by a numerical simulation method. The welding joint considered three weld joint angles of 40 deg., 6 deg. and 2 deg. Computations were made using a 2-D finite element model based on the simulation of cooling from the heat treatment temperature to room temperature with two cooling conditions at the inside surface. In these results, it is shown that the residual stress increased at the inner surface, when water cooling was applied to the inner surface, and axial compressive residual stress increased at the inner surface when the joint angle was decreased. (authors)

  8. Computer-aided joint space analysis of the metacarpal-phalangeal and proximal-interphalangeal finger joint: normative age-related and gender-specific data

    Energy Technology Data Exchange (ETDEWEB)

    Pfeil, Alexander; Boettcher, Joachim; Seidl, Bettina E.; Heyne, Jens-Peter; Petrovitch, Alexander; Mentzel, Hans-Joachim; Kaiser, Werner A. [Friedrich-Schiller-University Jena, Institute of Diagnostic and Interventional Radiology, Jena (Germany); Eidner, Torsten; Wolf, Gunter; Hein, Gert [Friedrich-Schiller-University Jena, Department of Rheumatology and Osteology, Clinic of Internal Medicine III, Jena (Germany)


    The purpose of the study was to provide reference data for computer-aided joint space analysis based on a semi-automated and computer-aided diagnostic system for the measurement of metacarpal-phalangeal and proximal-interphalangeal finger joint widths; additionally, the determination of sex differences and the investigation of changes in joint width with age were evaluated. Eighty hundred and sixty-nine patients (351 female and 518 male) received radiographs of the hand for trauma and were screened for a host of conditions known to affect the joint spaces. All participants underwent measurements of joint space distances at the metacarpal-phalangeal articulation (JSD-MCP) from the thumb to the small finger and at the proximal-interphalangeal articulation (JSD-PIP) from the index finger to the small finger using computer-aided diagnosis technology with semi-automated edge detection. The study revealed an annual narrowing of the JSD of 0.6% for the JSD-MCP and for the JSD-PIP. Furthermore, the data demonstrated a notable age-related decrease in JSD, including an accentuated age-related joint space narrowing in women for both articulations. Additionally, males showed a significantly wider JSD-MCP (+11.1%) and JSD-PIP (+15.4%) compared with the female cohort in all age groups. Our data presented gender-specific and age-related normative reference values for computer-aided joint space analysis of the JSD-MCP and JSD-PIP that could be used to identify disease-related joint space narrowing, particularly in patients with osteoarthritis and rheumatoid arthritis commonly involving the peripheral small hand joints. (orig.)

  9. Large-System Analysis of Joint User Selection and Vector Precoding for Multiuser MIMO Downlink

    CERN Document Server

    Takeuchi, Keigo; Kawabata, Tsutomu


    Joint user selection (US) and vector precoding (US-VP) is proposed for multiuser multiple-input multiple-output (MU-MIMO) downlink. The main difference between joint US-VP and conventional US is that US depends on data symbols for joint US-VP, whereas conventional US is independent of data symbols. The replica method is used to analyze the performance of joint US-VP in the large-system limit, where the numbers of transmit antennas, users, and selected users tend to infinity while their ratios are kept constant. The analysis under the assumptions of replica symmetry (RS) and 1-step replica symmetry breaking (1RSB) implies that optimal data-independent US provides nothing but the same performance as random US in the large-system limit, whereas data-independent US is capacity-achieving as only the number of users tends to infinity. It is shown that joint US-VP can provide a substantial reduction of the energy penalty in the large-system limit. Consequently, joint US-VP outperforms separate US-VP in terms of the ...

  10. Jointly Decoded Raptor Codes: Analysis and Design for the BIAWGN Channel

    Directory of Open Access Journals (Sweden)

    Venkiah Auguste


    Full Text Available Abstract We are interested in the analysis and optimization of Raptor codes under a joint decoding framework, that is, when the precode and the fountain code exchange soft information iteratively. We develop an analytical asymptotic convergence analysis of the joint decoder, derive an optimization method for the design of efficient output degree distributions, and show that the new optimized distributions outperform the existing ones, both at long and moderate lengths. We also show that jointly decoded Raptor codes are robust to channel variation: they perform reasonably well over a wide range of channel capacities. This robustness property was already known for the erasure channel but not for the Gaussian channel. Finally, we discuss some finite length code design issues. Contrary to what is commonly believed, we show by simulations that using a relatively low rate for the precode , we can improve greatly the error floor performance of the Raptor code.

  11. The double universal joint wrist on a manipulator: Solution of inverse position kinematics and singularity analysis (United States)

    Williams, Robert L., III


    This paper presents three methods to solve the inverse position kinematics position problem of the double universal joint attached to a manipulator: (1) an analytical solution for two specific cases; (2) an approximate closed form solution based on ignoring the wrist offset; and (3) an iterative method which repeats closed form position and orientation calculations until the solution is achieved. Several manipulators are used to demonstrate the solution methods: cartesian, cylindrical, spherical, and an anthropomorphic articulated arm, based on the Flight Telerobotic Servicer (FTS) arm. A singularity analysis is presented for the double universal joint wrist attached to the above manipulator arms. While the double universal joint wrist standing alone is singularity-free in orientation, the singularity analysis indicates the presence of coupled position/orientation singularities of the spherical and articulated manipulators with the wrist. The cartesian and cylindrical manipulators with the double universal joint wrist were found to be singularity-free. The methods of this paper can be implemented in a real-time controller for manipulators with the double universal joint wrist. Such mechanically dextrous systems could be used in telerobotic and industrial applications, but further work is required to avoid the singularities.

  12. Finite element normal mode analysis of resistance welding jointed of dissimilar plate hat structure (United States)

    Nazri, N. A.; Sani, M. S. M.


    Structural joints offer connection between structural element (beam, plate, solid etc.) in order to build a whole assembled structure. The complex behaviour of connecting elements plays a valuable role in characteristics of dynamic such as natural frequencies and mode shapes. In automotive structures, the trustworthiness arrangement of the structure extremely depends on joints. In this paper, top hat structure is modelled and designed with spot welding joint using dissimilar materials which is mild steel 1010 and stainless steel 304, using finite element software. Different types of connector elements such as rigid body element (RBE2), welding joint element (CWELD), and bar element (CBAR) are applied to represent real connection between two dissimilar plates. Normal mode analysis is simulated with different types of joining element in order to determine modal properties. Natural frequencies using RBE2, CBAR and CWELD are compared to equivalent rigid body method. Connection that gives the lowest percentage error among these three will be selected as the most reliable joining for resistance spot weld. From the analysis, it is shown that CWELD is better compared to others in term of weld joining among dissimilar plate materials. It is expected that joint modelling of finite element plays significant role in structural dynamics.

  13. TETIG diagrams - a new way to optimise the design parameters and heat treatment of joints made in high-temperature brazing alloys. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R. (UKAEA Springfields Nuclear Power Development Labs.)


    The applications and problems of brazing are reviewed. Phase studies with the braze filler metal chosen for the LMFBR 9% Cr 1% Mo tube-in-tube joint work (BNi4), are discussed, with special reference to the problem of how to eliminate the centre-line eutectics containing hard, brittle compounds. A TETIG diagram is explained with reference to the variables (1) temperature of brazing operation; (2) time of soaking at temperature; and (3) the gap within the joints. Experiments are reported on brazing specimens of AISI 321 stainless steel, using braze filler metals containing various proportions of boron and silicon as the melting point temperature depressant. TETIG diagrams are constructed and used to predict how to optimize further joints. Micrographs show the effects of the variables on the microstructures.

  14. Thermoelastic stress analysis of a pultruded composite double lap joint (United States)

    Hemann, John H.; Martin, Richard E.; Mandic, Davor G.


    The use of composite materials, in particular glass/epoxy systems for structural applications has seen widespread growth. Recent examples include a bridge in Butler County, Ohio and a covered pedestrian bridge that is scheduled to be installed in Akron, Ohio. Both of these structures employ pultruded composites for the main structural members due to their high strength, light weight and the ease of manufacture into common structural shapes such as wide flanges, I-beams and box sections. The use of these shapes gives the designer the ability to use many of the same types of structural details that are common to steel design. This paper will examine the most common method of joining structural members, bolted connections. The analysis of bolted connections in composite materials has been widely reported in the literature. Analysis methods have ranged from two and three dimensional finite element analysis to more empirical methods of calculating the stress concentration factors based on experimental data. This paper will focus on the use of the thermoelastic stress analysis method to determine the stress concentration around a steel pin loaded in double shear by a pultruded glass fiber composite. Further studies were conducted to determine the time dependent material behavior on the thermoelastic stress analysis signal output. The following is a description of the theory, experimental setup, and a summary of results.

  15. The analysis of beryllium-copper diffusion joint after HHF test

    Energy Technology Data Exchange (ETDEWEB)

    Guiniatouline, R.N.; Mazul, I.V. [Efremov Research Institute, St. Petersburg (Russian Federation); Rubkin, S.Y. [Institute of Physical Chemistry, Moscow (Russian Federation)] [and others


    The development of beryllium-copper joints which can withstand to relevant ITER divertor conditions is one of the important tasks at present time. One of the main problem for beryllium-copperjoints, is the inter-metallic layers, the strength and life time of joints significantly depends from the width and contents of the intermetallic layers. The objective of this work is to study the diffusion joint of TGP-56 beryllium to OFHC copper after thermal response and thermocyclic tests with beryllium-copper mockup. The BEY test were performed at e-beam facility (EBTS, SNLA). The following methods were used for analyses: the roentgenographic analysis; X-ray spectrum analysis; the fracture graphic analysis. During the investigation the followed studies were done: the analysis of diffusion boundary Be-Cu, which was obtained at the crossection of one of the tiles, the analysis of the debonded surfaces of a few beryllium tiles and corresponding copper parts; the analysis of upper surface of one of the tiles after HHF tests. The results of this work have showed that: the joint roentgenographic and elements analyses indicated the following phases in the diffusion zone: Cu{sub 2}Be ({approximately}170 {mu}m), CuBe ({approximately}30{mu}m), CuBe{sub 2} ({approximately}1 {mu}m) and solid solution of copper in beryllium. The phases Cu{sub 2}Be, CuBe and solid solution of copper in beryllium were indicated using quantitative microanalysis and phases CuBe, CuBe{sub 2}, Cu, Be - by roentgenographic analysis; the source of fracture (initial crack) is located in the central part of the tiles, the crack caused by the influence of residual stresses during cooling of a mock-up after fabrication and developed under the conditions of slow elastic-plastic growing during the process of thermal fatigue testing. The analysis gives the important data about joint`s quality and also may be used for any type of joints and its comparison for ITER applications.

  16. Comparative Analysis of Welded and Adhesive Joints Strength Made of Acid-Resistant Stainless Steel Sheets

    Directory of Open Access Journals (Sweden)

    Izabela Miturska


    Full Text Available The article presents the selected results of strength tests on the effectiveness of bonding high-alloy steel 1.4310. Sheet steel is one of the materials that are difficult to activate energy. Effective joining of it is difficult, requires selection of the appropriate bonding technology. The paper focuses on the comparative tests the shear strength of one-single lap welded and bonded joints. The welding process was performed 3 groups of samples TIG welding and argon, where the variable value of the welding process was current: 60A, 70A, 80A. The adhesion process was performed in 6 groups of samples which differed in the method of surface preparation and the type of the adhesive. Adhesive joints were made by using adhesive of epoxy resin and a hardener: Epidian 61/TFF at a mass ratio of 100:22 and Epidian 61/IDA at a mass ratio of 100:40. As a way of surface preparation applied 3 different, but simplified and environmentally friendly methods of surface preparation: degreasing with using cleaner Loctite 7061, abrasive machining with P320 and degreasing and grinding with abrasive T800 and degreasing were used. Make joints and curing the adhesive joints were carried out at ambient temperature. Analyzed the joints were tested destructive - which set out the shear strength, in accordance with DIN EN 1465 on the testing machine Zwick / Roell Z150. Based on the results of research it was found that better results were obtained for the maximum welded joints, but this result was similar to the maximum value of the strength of the adhesive bond.

  17. Joint Temperature-Lasing Mode Compensation for Time-of-Flight LiDAR Sensors

    Directory of Open Access Journals (Sweden)

    Anas Alhashimi


    Full Text Available We propose an expectation maximization (EM strategy for improving the precision of time of flight (ToF light detection and ranging (LiDAR scanners. The novel algorithm statistically accounts not only for the bias induced by temperature changes in the laser diode, but also for the multi-modality of the measurement noises that is induced by mode-hopping effects. Instrumental to the proposed EM algorithm, we also describe a general thermal dynamics model that can be learned either from just input-output data or from a combination of simple temperature experiments and information from the laser’s datasheet. We test the strategy on a SICK LMS 200 device and improve its average absolute error by a factor of three.

  18. Joint analysis of binary and quantitative traits with data sharing and outcome-dependent sampling. (United States)

    Zheng, Gang; Wu, Colin O; Kwak, Minjung; Jiang, Wenhua; Joo, Jungnam; Lima, Joao A C


    We study the analysis of a joint association between a genetic marker with both binary (case-control) and quantitative (continuous) traits, where the quantitative trait values are only available for the cases due to data sharing and outcome-dependent sampling. Data sharing becomes common in genetic association studies, and the outcome-dependent sampling is the consequence of data sharing, under which a phenotype of interest is not measured for some subgroup. The trend test (or Pearson's test) and F-test are often, respectively, used to analyze the binary and quantitative traits. Because of the outcome-dependent sampling, the usual F-test can be applied using the subgroup with the observed quantitative traits. We propose a modified F-test by also incorporating the genotype frequencies of the subgroup whose traits are not observed. Further, a combination of this modified F-test and Pearson's test is proposed by Fisher's combination of their P-values as a joint analysis. Because of the correlation of the two analyses, we propose to use a Gamma (scaled chi-squared) distribution to fit the asymptotic null distribution for the joint analysis. The proposed modified F-test and the joint analysis can also be applied to test single trait association (either binary or quantitative trait). Through simulations, we identify the situations under which the proposed tests are more powerful than the existing ones. Application to a real dataset of rheumatoid arthritis is presented. © 2012 Wiley Periodicals, Inc.

  19. Digital image correlation in analysis of striffness in local zones of welded joints

    Czech Academy of Sciences Publication Activity Database

    Milosevic, M.; Milosevic, N.J.; Sedmak, S.; Tatic, U.; Mitrovic, N.; Hloch, Sergej; Jovicic, R.


    Roč. 23, č. 1 (2016), s. 19-24 ISSN 1330-3651 Institutional support: RVO:68145535 Keywords : Aramis software * digital image correlation * strain analysis * stiffness * welded joints Subject RIV: JQ - Machines ; Tools Impact factor: 0.723, year: 2016

  20. Stress analysis of un-lapped rectangular hollow 'k' joints by the finite ...

    African Journals Online (AJOL)

    Finite element stress analysis relevant for the study of welded hollow rectangular 'K' Joints is presented. Thin shell theory and iso-parametric formulation are employed to obtain equilibrium equations. Thereafter, the effect of brace spacing is investigated by varying the spacing between the two braces and making computer ...

  1. Joint analysis of Esener-2, the LFS 2013 ad hoc module and the 6th EWCS

    NARCIS (Netherlands)

    Houtman, I.L.D.; Eekhout, I.; Venema, A.; Bakhuys Roozeboom, M.M.C.; Buuren, S. van


    Psychosocial risk management, psychosocial risks and the role of drivers and barriers: results from a multilevel joint analysis of three major European surveys. The aim of this study was to provide answers to questions concerning OSH risk management, and in particular psychosocial risk management:

  2. Failure analysis of bolted joints in foam-core sandwich composites

    DEFF Research Database (Denmark)

    Zabihpoor, M.; Moslemian, Ramin; Afshin, M.


    using 3D FEM in ANSYS commercial code. Tsai-Wu failure criterion is used in the failure analysis. The results indicate that the most important parameter in the proposed joint zone design is the foam -solid laminate interface angle which plays an important role on the value of failure criterion (damage...

  3. Dissipative properties of materials with microplastic mechanism of damping under conditions of separate and joint action of static stresses and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Shpak, D.E.


    Static stress and temperature are studied experimentally for their separate and joint effect on dissipative properties of VT3-1 and Ehp 718 alloys whose dissipation energy is conditioned by microplastic strains. The results of the study are presented. It is shown that for the materials studied in contrast to the materials with other basic damping mechanisms joint effect of static stresses and temperature is close to a simple summation of the separate effect of these factors without any changes in the character of energy dissipation dependence.

  4. Reliability Analysis for Adhesive Bonded Composite Stepped Lap Joints Loaded in Fatigue

    DEFF Research Database (Denmark)

    Kimiaeifar, Amin; Sørensen, John Dalsgaard; Lund, Erik


    This paper describes a probabilistic approach to calculate the reliability of adhesive bonded composite stepped lap joints loaded in fatigue using three- dimensional finite element analysis (FEA). A method for progressive damage modelling is used to assess fatigue damage accumulation and residual...... by the wind turbine standard IEC 61400-1. Finally, an approach for the assessment of the reliability of adhesive bonded composite stepped lap joints loaded in fatigue is presented. The introduced methodology can be applied in the same way to calculate the reliability level of wind turbine blade components...

  5. Finite element analysis of Ti-based knee-joint implant

    Directory of Open Access Journals (Sweden)

    L. Zach


    Full Text Available The focus of this paper was on finite element analysis of a PROSPON oncological knee endoprosthesis. The 3D CAD knee joint model, the designed FE PROSPON prosthesis model into which was integrated, was created on the basis of Visible Human Project CT scans. Analyses of stress state and contact pressures were performed in the kneebending position within 15,4° - 69,4° hip joint flection range. The results showed that the maximum achieved stress did not exceed the yield strength (90 MPa of the material. The results of the stress state were in accordance with the distribution of contact pressure.

  6. Scarf Joint Modeling and Analysis of Composite Materials (United States)


    MODELING AND ANALYSIS OF COMPOSITE MATERIALS by Armando Marrón June 2009 Thesis Advisor: Young W. Kwon Second Reader: Douglas C. Loup THIS...June 2009 Author: Armando Marrón Approved by: Professor Young W. Kwon Thesis Advisor Douglas C. Loup Second Reader...W. Kwon Naval Postgraduate School Monterey, California 4. Douglas C. Loup Naval Surface Warfare Center, Carderock Division West Bethesda

  7. Statistical analysis of joint toxicity in biological growth experiments

    DEFF Research Database (Denmark)

    Spliid, Henrik; Tørslev, J.


    The authors formulate a model for the analysis of designed biological growth experiments where a mixture of toxicants is applied to biological target organisms. The purpose of such experiments is to assess the toxicity of the mixture in comparison with the toxicity observed when the toxicants are...... is applied on data from an experiment where inhibition of the growth of the bacteria Pseudomonas fluorescens caused by different mixtures of pentachlorophenol and aniline was studied....

  8. The return period analysis of natural disasters with statistical modeling of bivariate joint probability distribution. (United States)

    Li, Ning; Liu, Xueqin; Xie, Wei; Wu, Jidong; Zhang, Peng


    New features of natural disasters have been observed over the last several years. The factors that influence the disasters' formation mechanisms, regularity of occurrence and main characteristics have been revealed to be more complicated and diverse in nature than previously thought. As the uncertainty involved increases, the variables need to be examined further. This article discusses the importance and the shortage of multivariate analysis of natural disasters and presents a method to estimate the joint probability of the return periods and perform a risk analysis. Severe dust storms from 1990 to 2008 in Inner Mongolia were used as a case study to test this new methodology, as they are normal and recurring climatic phenomena on Earth. Based on the 79 investigated events and according to the dust storm definition with bivariate, the joint probability distribution of severe dust storms was established using the observed data of maximum wind speed and duration. The joint return periods of severe dust storms were calculated, and the relevant risk was analyzed according to the joint probability. The copula function is able to simulate severe dust storm disasters accurately. The joint return periods generated are closer to those observed in reality than the univariate return periods and thus have more value in severe dust storm disaster mitigation, strategy making, program design, and improvement of risk management. This research may prove useful in risk-based decision making. The exploration of multivariate analysis methods can also lay the foundation for further applications in natural disaster risk analysis. © 2012 Society for Risk Analysis.

  9. Analysis of Balanced Double Lap Joints with a Bi-Linear Softening Adhesive

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik; Schmidt, Jacob Wittrup


    relationships is needed. A constitutive relationship containing a bi-linear softening law contains such versatility. The solution was investigated for moderate and extreme softening parameters. The solution for extreme softening parameters, exhibited a non-physical behavior, where the size of the stress......-free crack decreased for increasing size of fracture process zone. This suggests that in order to fully describe the loading and unloading response, an unloading law should be implemented in the constitutive model. Apart from adhesively bonded metallic joints, the present solution may be used in analysis......The response of a bonded symmetric balanced double lap joint under tensile loading with a bilinear softening adhesive is described with a closed form solution. Since bonded joints in concrete structures undergo softening, a versatile model to describe the response for a wide range of constitutive...

  10. Detailed investigation of the analysis conditions in the evaluation of bonded joints by cohesive zone models (United States)

    Rocha, R. J. B.; Campilho, R. D. S. G.


    Cohesive Zone Models (CZM) are widely used for the strength prediction of adhesive joints. This work studies the influence of different conditions used in CZM simulations to model a thin adhesive layer in single-lap joints (SLJ) under a tensile loading, for an estimation of their influence on the strength prediction under diverse geometrical and material conditions. Adhesives ranging from brittle to highly ductile and overlap lengths (LO) between 12.5 and 50 mm were considered. Several damage initiation and growth criteria were tested. The analysis carried out in this work allowed to conclude that CZM is a powerful technique for strength prediction of bonded joints, provided that the modelling conditions are properly defined.

  11. Finite element mesh generation and analysis of solder joints for fatigue life predictions (United States)

    Paydar, Nasser H.; Tong, Yihong; Akay, Hasan U.; Boehmer, William


    Tools for fatigue life prediction of solder joints are developed. This report consists of two parts. In part One, the creep and plastic deformations stored in a solder joint are calculated by implementing appropriate plastic and creep constitutive models in a nonlinear finite element program. The calculated damage in each cycle is then related to the life of the material using two failure criteria: strain-life and energy-partitioning. The importance of parameters affecting the fatigue life of solders are evaluated. In part Two, the finite element analysis is combined with x-ray and laser imaging systems, from which real solder joint geometries can be constructed. The approaches presented herein provides a useful tool in the design and manufacturing of surface-mount assemblies.

  12. Mechanical Performance and Parameter Sensitivity Analysis of 3D Braided Composites Joints

    Directory of Open Access Journals (Sweden)

    Yue Wu


    Full Text Available 3D braided composite joints are the important components in CFRP truss, which have significant influence on the reliability and lightweight of structures. To investigate the mechanical performance of 3D braided composite joints, a numerical method based on the microscopic mechanics is put forward, the modeling technologies, including the material constants selection, element type, grid size, and the boundary conditions, are discussed in detail. Secondly, a method for determination of ultimate bearing capacity is established, which can consider the strength failure. Finally, the effect of load parameters, geometric parameters, and process parameters on the ultimate bearing capacity of joints is analyzed by the global sensitivity analysis method. The results show that the main pipe diameter thickness ratio γ, the main pipe diameter D, and the braided angle α are sensitive to the ultimate bearing capacity N.

  13. Development of Non-Conservative Joints in Beam Networks for Vibration Energy Flow Analysis

    Directory of Open Access Journals (Sweden)

    Jee-Hun Song


    Full Text Available Our work aims to find a general solution for the vibrational energy flow through a plane network of beams on the basis of an energy flow analysis. A joint between two semi-infinite beams are modeled by three sets of springs and dashpots. Thus, the results can incorporate the case of complaint and non-conservative in all the three degrees of freedom. In the cases of finite coupled structures connected at a certain angle, the derived non-conservative joints and developed wave energy equation were applied. The joint properties, the frequency, the coupling angle, and the internal loss factor were changed to evaluate the proposed methods for predicting medium-to-high frequency vibrational energy and intensity distributions.

  14. Analysis and Design Optimization of a Compact and Lightweight Joint Torque Sensor for Space Manipulators

    Directory of Open Access Journals (Sweden)

    Nanzhe Wei


    Full Text Available This paper describes the development of a compact and lightweight joint torque sensor for space manipulators. Space manipulators with torque sensors can not only apply force control approach to more precise and more dexterous space missions, but also monitor the occurrence of unpredicted events as accidental impacts with objects they have to manipulate. At present, most of the compact torque sensors, designed without consideration of space environment, cannot be directly used in space applications. In this paper, we propose a compact and lightweight design for the joint torque sensor based on strain gauge, for the reason of good physical, chemical, and mechanical stabilities under high temperature environment. In addition, to reduce the interferences by axial forces generated by assembling condition and joint motors, the structural optimization for the sensing element is carried out. The proposed design is simulated by FEM software ANSYS, and it shows successful measurements of the torque with a load capacity of 10 Nm, which is sufficient for the torque generated in robot joints. The effect of axial loading is also analyzed by ANSYS. The designed sensor is manufactured by duralumin alloy. The calibration for the sensor is carried out, and several experiments are conducted to ensure its feasibility with the space manipulator.

  15. Analysis of the Constraint Joint Loading in the Thumb During Pipetting (United States)

    Sinsel, Erik W.; Zhao, Kristin D.; An, Kai-Nan; Buczek, Frank L.


    Dynamic loading on articular joints is essential for the evaluation of the risk of the articulation degeneration associated with occupational activities. In the current study, we analyzed the dynamic constraint loading for the thumb during pipetting. The constraint loading is considered as the loading that has to be carried by the connective tissues of the joints (i.e., the cartilage layer and the ligaments) to maintain the kinematic constraints of the system. The joint loadings are solved using a classic free-body approach, using the external loading and muscle forces, which were obtained in an inverse dynamic approach combined with an optimization procedure in anybody. The constraint forces in the thumb joint obtained in the current study are compared with those obtained in the pinch and grasp tests in a previous study (Cooney and Chao, 1977, “Biomechanical Analysis of Static Forces in the Thumb During Hand Function,” J. Bone Joint Surg. Am., 59(1), pp. 27–36). The maximal compression force during pipetting is approximately 83% and 60% greater than those obtained in the tip pinch and key pinch, respectively, while substantially smaller than that obtained during grasping. The maximal lateral shear force is approximately six times, 32 times, and 90% greater than those obtained in the tip pinch, key pinch, and grasp, respectively. The maximal dorsal shear force during pipetting is approximately 3.2 and 1.4 times greater than those obtained in the tip pinch and key pinch, respectively, while substantially smaller than that obtained during grasping. Our analysis indicated that the thumb joints are subjected to repetitive, intensive loading during pipetting, compared to other daily activities. PMID:25839321

  16. Thermo-mechanic and Microstructural Analysis of an Underwater Welding Joint


    Pedro Hernández Gutiérrez; Francisco Cepeda Rodríguez; Jose Jorge Ruiz Mondragón; Jorge Leobardo Acevedo Dávila; Martha Patricia Guerrero Mata; Carlos Alberto Guevara Chavez


    Abstract The aim of this research is to present a comparative analysis between theoretical and experimental thermal fields as well as a microstructural behaviour and residual stresses applying multiple weld beads in the joint of two API 5L X52 pipe sections. The thermal field, microstructural and residual stresses were numerically modelled through the finite element method (FEM) and compared to experimentally. The simulation conditions used in the FEM analysis were similar considerations to t...

  17. The joint influence of photoperiod and temperature during growth cessation and development of dormancy in white spruce (Picea glauca). (United States)

    Hamilton, Jill A; El Kayal, Walid; Hart, Ashley T; Runcie, Daniel E; Arango-Velez, Adriana; Cooke, Janice E K


    in the following season, which is particularly important for a determinate species such as white spruce. The joint influence of these environmental cues points toward the importance of including local constant photoperiod and shifting temperature cues into predictive models that consider how climate change may affect northern forests. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email:

  18. Joint Analysis of Bulk Wildfire Characteristics from Multiple Satellite Retrievals (United States)

    Tang, W.; Arellano, A. F.


    Biomass burning significantly impacts atmospheric composition, as well as regional and global climate. Here, we investigate the spatiotemporal trends in fire characteristics in several major fire regions using combustion signatures observed from space. Our main goals is to identify key relationships between the trends in co-emitted constituents across these regions, as well as linkages to main drivers of change such as meteorology, fire practice, development patterns, and ecosystem feedbacks. Our approach begins with a multi-species analysis of trends in the observed abundance of CO, NO2, and aerosols over these regions and across the time period 2005 to 2014. We use MOPITT multi-spectral CO, OMI tropospheric NO2 column, MODIS AOD, and MODIS FRP retrievals. The long records from these retrievals provide a unique opportunity to study atmospheric composition across the most recent decade. While several studies in the past have reported trends over these regions, most of these studies have focused on a particular constituent. A unique aspect of this work involves understanding co-variations in co-emitted constituents to provide a more comprehensive look at fire characteristics, which are yet to be fully understood. Here, we introduce a derived quantity (called smoke index) to represent bulk fire characteristics (e.g., flaming versus smoldering). The smoke index is calculated as the ratio of the geometric mean of CO and AOD fire enhancements to that of NO2 fire enhancements. Our initial results, which focused on the Amazon region, show that: 1) deforestation fires are dominantly flaming fires while non-deforestation fires are more likely to be dominantly smoldering fires; and 2) droughts have larger influence on non-deforestation (possibly understorey) fires than deforestation fires. Here, we will present an extension of this analysis to other fire regions around the globe (tropical, temperate and boreal fires) and explore other measurements available during this

  19. Finite element modelling and updating of friction stir welding (FSW joint for vibration analysis

    Directory of Open Access Journals (Sweden)

    Zahari Siti Norazila


    Full Text Available Friction stir welding of aluminium alloys widely used in automotive and aerospace application due to its advanced and lightweight properties. The behaviour of FSW joints plays a significant role in the dynamic characteristic of the structure due to its complexities and uncertainties therefore the representation of an accurate finite element model of these joints become a research issue. In this paper, various finite elements (FE modelling technique for prediction of dynamic properties of sheet metal jointed by friction stir welding will be presented. Firstly, nine set of flat plate with different series of aluminium alloy; AA7075 and AA6061 joined by FSW are used. Nine set of specimen was fabricated using various types of welding parameters. In order to find the most optimum set of FSW plate, the finite element model using equivalence technique was developed and the model validated using experimental modal analysis (EMA on nine set of specimen and finite element analysis (FEA. Three types of modelling were engaged in this study; rigid body element Type 2 (RBE2, bar element (CBAR and spot weld element connector (CWELD. CBAR element was chosen to represent weld model for FSW joints due to its accurate prediction of mode shapes and contains an updating parameter for weld modelling compare to other weld modelling. Model updating was performed to improve correlation between EMA and FEA and before proceeds to updating, sensitivity analysis was done to select the most sensitive updating parameter. After perform model updating, total error of the natural frequencies for CBAR model is improved significantly. Therefore, CBAR element was selected as the most reliable element in FE to represent FSW weld joint.

  20. Analysis of pain and painless symptoms in temporomandibular joints dysfunction in adult patients. (United States)

    Górecka, Małgorzata; Pihut, Małgorzata; Kulesa-Mrowiecka, Małgorzata


    Recent years have shown an increase in the number of patients reporting for treatment of pain due to musculoskeletal joint, associated with temporomandibular joint dysfunction. Therefore, studies were undertaken, aimed at analyzing the symptoms of the dysfunction, because of which patients come to the prosthetic treatment. Aim of the thesis: The aim of the study was a retrospective analysis of symptoms of temporomandibular joint dysfunction reported by patients diagnosed with this problem. The research material was a retrospective medical records of 120 patients, aged 19 to 45 years who have taken prosthetic treatment due to temporomandibular joint dysfunction in the Consulting Room in Prosthetics Department in Kraków, from June 2015 to December 2016. During the test patients, in addition to interviewing a physician, completed a personal survey in their own study. The material has been divided into I group of patients who reported pain form of dysfunction and II group, who had no symptoms of pain within the stomatognatic system. The analysis covered type of symptoms, the share of local factors (para-functions) and systemic, as well as the time a er which the patients reported for the treatment of functional disorders since the appearance of the first symptoms. Analysis of the research material showed that the main reason for reporting patients was pain in one or both temporal joints of significant intensity (5 to 8 in VAS scale,) accompanied by acoustic symptoms. A large group of questioners reported problems with the range of jaw movement and head and face pain, as well as subjective symptoms from the auditory, sight, neck, neck and shoulder areas.

  1. Analysis of provider specialties in the treatment of patients with clinically diagnosed back and joint problems. (United States)

    Wilson, Fernando A; Licciardone, John C; Kearns, Cathleen M; Akuoko, Mathias


    Although several studies have compared patient outcomes by provider specialty in the treatment of back and joint pain, little is known about the cost-effectiveness of improving patient outcomes across specialties. This study uses a large-scale, nationally representative database to evaluate the cost-effectiveness of being treated by specific provider specialists for back and joint pain in the United States. The 2002-2012 Medical Expenditure Panel Surveys were used to examine patients diagnosed with back and/or joint problems seeking treatment from doctors (internal medicine, family/general, osteopathic medicine, orthopaedics, rheumatology, neurology) or other providers (chiropractor, physical therapist, acupuncturist, massage therapist). A total of 16,546 respondents aged 18 to 85 and clinically diagnosed with back/joint pain were examined. Self-reported measures of physical and mental health and general quality of life (measured by the EuroQol-5D) were compared with average total costs of treatment across medical providers. Total annual treatment costs per person ranged from $397 for family/general doctors to $1205 for rheumatologists. Cost-effectiveness analysis suggests that osteopathic, family/general, internal medicine doctors and chiropractors and massage therapists were more cost-effective than other specialties in improving physical function to back pain patients. For mental health measures, family/general and orthopaedic doctors and physical therapists were more cost-effective compared with other specialties. Similar to results on physical function, family/general, osteopathic and internal medicine doctors dominated other specialties. However, only massage therapy was cost-effective among non-doctor providers in improving quality of life measures. Patients seeking care for back and joint-related health problems face a wide range of treatments, costs and outcomes depending on which specialist provider they see. This study provides important insight on the

  2. Austenitic Steels at Low Temperature: Joint International Cryogenic Engineering Conference and International Cryogenic Materials Conference

    CERN Document Server

    Horiuchi, T; ICEC-ICMC


    The need for alternate energy sources has led to the develop­ ment of prototype fusion and MHD reactors. Both possible energy systems in current designs usually require the use of magnetic fields for plasma confinement and concentration. For the creation and maintenance of large 5 to 15 tesla magnetic fields, supercon­ ducting magnets appear more economical. But the high magnetic fields create large forces, and the complexities of the conceptual reactors create severe space restrictions. The combination of re­ quirements, plus the desire to keep construction costs at a mini­ mum, has created a need for stronger structural alloys for service at liquid helium temperature (4 K). The complexity of the required structures requires that these alloys be weldable. Furthermore, since the plasma is influenced by magnetic fields and since magnet­ ic forces from the use of ferromagnetic materials in many configur­ ations may be additive, the best structural alloy for most applica­ tions should be nonmagnetic. Thes...

  3. Indwelling versus Intermittent Urinary Catheterization following Total Joint Arthroplasty: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available The purpose of this study is to compare the rates of urinary tract infection (UTI and postoperative urinary retention (POUR in patients undergoing lower limb arthroplasty after either indwelling urinary catheterization or intermittent urinary catheterization.We conducted a meta-analysis of relevant randomized controlled trials (RCT to compare the rates of UTI and POUR in patients undergoing total joint arthroplasty after either indwelling urinary catheterization or intermittent urinary catheterization. A comprehensive search was carried out to identify RCTs. Study-specific risk ratios (RR with 95% confidence intervals (CI were pooled. Additionally, a meta-regression analysis, as well as a sensitivity analysis, was performed to evaluate the heterogeneity.Nine RCTs with 1771 patients were included in this meta-analysis. The results showed that there was no significant difference in the rate of UTIs between indwelling catheterization and intermittent catheterization groups (P>0.05. Moreover, indwelling catheterization reduced the risk of POUR, versus intermittent catheterization, in total joint surgery (P<0.01.Based on the results of the meta-analysis, indwelling urinary catheterization, removed 24-48 h postoperatively, was superior to intermittent catheterization in preventing POUR. Furthermore, indwelling urinary catheterization with removal 24 to 48 hours postoperatively did not increase the risk of UTI. In patients with multiple risk factors for POUR undergoing total joint arthroplasty of lower limb, the preferred option should be indwelling urinary catheterization removed 24-48 h postoperatively.Level I.

  4. Exploring the added value of imposing an ozone effect monotonicity constraint and of jointly modeling ozone and temperature effects in an epidemiologic study of air pollution and mortality (United States)

    Abstract: A number of epidemiologic studies have shown that both ozone and temperature are associated with increased risk for cardio-respiratory mortality and morbidity. However, their joint effects are not characterized as well as their independent effects. Furthermore, the i...

  5. Modelling of microstructural creep damage in welded joints of 316L stainless steel; Modelisation de l'endommagement a haute temperature dans le metal d'apport des joints soudes d'acier inoxydable austenitique

    Energy Technology Data Exchange (ETDEWEB)

    Bouche, G


    Welded joints of 316L stainless steel under service conditions at elevated temperature are known to be preferential sites of creep damage, as compared to the base material. This damage results in the formation of cavities and the development of creep cracks which can lead to a premature failure of welded components. The complex two-phase microstructure of 316L welds was simulated by manually filling a mould with longitudinal deposited weld beads. The moulded material was then aged during 2000 hours at 600 deg. C. High resolution Scanning Electron Microscopy was largely used to examine the microstructure of the simulated material before and after ageing. Smooth and notched creep specimens were cut from the mould and tested at 600 deg. C under various stress levels. A comparison of the lifetime versus nominal stress curves for the base and welded materials shows a greater dependence of the welded material to creep phenomena. Observation and EBSD analysis show that damage is preferentially located along the austenite grain boundaries. The stress and strain fields in the notched specimens were calculated by finite element method. A correlation of this field to the observed damage was made in order to propose a predictive law relating the creep damage to the mechanical conditions applied locally. Further mechanical tests and simulation on CT specimens and mode II tubular specimens allowed validating the model under various multiaxial loading conditions. (author)

  6. Clinical Benefits of Joint Mobilization on Ankle Sprains: A Systematic Review and Meta-Analysis. (United States)

    Weerasekara, Ishanka; Osmotherly, Peter; Snodgrass, Suzanne; Marquez, Jodie; de Zoete, Rutger; Rivett, Darren A


    To assess the clinical benefits of joint mobilization for ankle sprains. MEDLINE, MEDLINE In-Process, Embase, AMED, PsycINFO, CINAHL, Cochrane Library, PEDro, Scopus, SPORTDiscus, and Dissertations and Theses were searched from inception to June 2017. Studies investigating humans with grade I or II lateral or medial sprains of the ankle in any pathologic state from acute to chronic, who had been treated with joint mobilization were considered for inclusion. Any conservative intervention was considered as a comparator. Commonly reported clinical outcomes were considered such as ankle range of movement, pain, and function. After screening of 1530 abstracts, 56 studies were selected for full-text screening, and 23 were eligible for inclusion. Eleven studies on chronic sprains reported sufficient data for meta-analysis. Data were extracted using the participants, interventions, comparison, outcomes, and study design approach. Clinically relevant outcomes (dorsiflexion range, proprioception, balance, function, pain threshold, pain intensity) were assessed at immediate, short-term, and long-term follow-up points. Methodological quality was assessed independently by 2 reviewers, and most studies were found to be of moderate quality, with no studies rated as poor. Meta-analysis revealed significant immediate benefits of joint mobilization compared with comparators on improving posteromedial dynamic balance (P=.0004), but not for improving dorsiflexion range (P=.16), static balance (P=.96), or pain intensity (P=.45). Joint mobilization was beneficial in the short-term for improving weight-bearing dorsiflexion range (P=.003) compared with a control. Joint mobilization appears to be beneficial for improving dynamic balance immediately after application, and dorsiflexion range in the short-term. Long-term benefits have not been adequately investigated. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Joint Motion Quality in Chondromalacia Progression Assessed by Vibroacoustic Signal Analysis. (United States)

    Bączkowicz, Dawid; Majorczyk, Edyta


    Because of the specific biomechanical environment of the patellofemoral joint, chondral disorders, including chondromalacia, often are observed in this articulation. Chondromalacia via pathologic changes in cartilage may lead to qualitative impairment of knee joint motion. To determine the patellofemoral joint motion quality in particular chondromalacia stages and to compare with controls. Retrospective, comparative study. Voivodship hospitals, university biomechanical laboratory. A total of 89 knees with chondromalacia (25 with stage I; 30 with stage II and 34 with stage III) from 50 patients and 64 control healthy knees (from 32 individuals). Vibroacoustic signal pattern analysis of joint motion quality. For all knees vibroacoustic signals were recorded. Each obtained signal was described by variation of mean square, mean range (R4), and power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) parameters. Differences between healthy controls and all chondromalacic knees as well as chondromalacia patellae groups were observed as an increase of analyzed parameters (P vibroacoustic signals, and there seems to be a relationship between the level of signal amplitude as well as frequency and cartilage destruction from the superficial layer to the subchondral bone. IV. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  8. Deconstructing the power resistance relationship for squats: A joint-level analysis. (United States)

    Farris, D J; Lichtwark, G A; Brown, N A T; Cresswell, A G


    Generating high leg power outputs is important for executing rapid movements. Squats are commonly used to increase leg strength and power. Therefore, it is useful to understand factors affecting power output in squatting. We aimed to deconstruct the mechanisms behind why power is maximized at certain resistances in squatting. Ten male rowers (age = 20 ± 2.2 years; height = 1.82 ± 0.03 m; mass = 86 ± 11 kg) performed maximal power squats with resistances ranging from body weight to 80% of their one repetition maximum (1RM). Three-dimensional kinematics was combined with ground reaction force (GRF) data in an inverse dynamics analysis to calculate leg joint moments and powers. System center of mass (COM) velocity and power were computed from GRF data. COM power was maximized across a range of resistances from 40% to 60% 1RM. This range was identified because a trade-off in hip and knee joint powers existed across this range, with maximal knee joint power occurring at 40% 1RM and maximal hip joint power at 60% 1RM. A non-linear system force-velocity relationship was observed that dictated large reductions in COM power below 20% 1RM and above 60% 1RM. These reductions were due to constraints on the control of the movement. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Evaluation of joint toxicity of nitroaromatic compounds and copper to Photobacterium phosphoreum and QSAR analysis. (United States)

    Su, Limin; Zhang, Xujia; Yuan, Xing; Zhao, Yuanhui; Zhang, Dongmei; Qin, Weichao


    The individual toxicities of Cu and 11 nitroaromatic compounds to Photobacterium phosphoreum were determined. The toxicity was expressed as the concentrations causing a 50% inhibition of bioluminescence after 15 min exposure (IC(50)). To evaluate the joint effect between the metal ion and the 11 nitroaromatic compounds, the joint toxicity of Cu and 11 nitroaromatic compounds were measured at different Cu concentrations (0.2IC(50), 0.5IC(50) and 0.8IC(50)), respectively. The result shows that the binary joint effect between Cu and nitroaromatic compounds is mainly simple addition at the low Cu concentration (0.2IC(50)). However, an antagonism effect, 55% and 64%, was observed between Cu and 11 nitroaromatic compounds for Cu at medium and high concentrations (0.5IC(50) and 0.8IC(50)). Quantitative structure-activity relationship (QSAR) analysis was performed to study the joint toxicity for the 11 nitroaromatic compounds. The result shows that the toxicity of nitroaromatic compounds is related to descriptors of Connolly solvent-excluded volume (CSEV) and dipolarity/polarizability (S) at low Cu concentration. On the other hand, the toxicity is related to Connolly accessible area (CAA) at medium and high Cu concentrations. The result indicates that different QSAR models on complex mixtures need to be developed to assess the ecological risk in real environments. Using single toxic data to evaluate the toxic effect of mixtures may result in wrong conclusions. Copyright © 2012 Elsevier B.V. All rights reserved.


    Directory of Open Access Journals (Sweden)

    Mirela COMAN


    Full Text Available The paper presents an analysis of wooden joints and ornaments used in construction of wooden churches built in XVIII-XIX centuries in Maramureș County, Romania. In the structure of wooden churches, Romanian masters revealed the wood - natural material and representative of Romanian culture and civilization of the Carpathian, faith-Christian monotheistic, Dacian population subsequently the only Roman people of the Carpathian basin which has cultivated such a faith, unlike existing polytheistic beliefs of the ancient peoples, woodworking skills that manifested from the creation of wood joints to ornaments and floral and geomorphic with sacred meaning to human existence. Wood joints, besides proving refinement and craftsmanship, good knowledge of proportions, showed the inclination to achieve balance of form - material - requests and tension accumulated in the structure of the wooden churches. This paper aims to present the triad: material - form - resistance (mechanical and over time the most important joints in wood used in the structure of the churches of Maramureș.

  11. Sensitivity analysis of flexible joint nonholonomic wheeled mobile manipulator in singular configuration (United States)

    Korayem, A. H.; Azimirad, V.; Binabaji, H.; Korayem, M. H.


    This paper proposes a method for decreasing jerk and increasing Maximum Allowable Load (MAL) of nonholonomic Wheeled Mobile Manipulator (WMM) considering flexibility of joints in singular conditions. The full dynamic model of nonholonomic WMM contains simultaneous operation of mobile base and manipulator with joint flexibility (in wheels and manipulator) which is presented here. The problem is formulated in terms of the optimal control which leads to a two point boundary value problem. Then Sobol's sensitivity analysis method is applied to determine the optimal values of flexible joint constants subject to the jerk minimization. To illustrate the proposed method, two categories of conditions are considered: conditions containing non-singular configuration and the singular conditions. An example is explained for non-singular condition of nonholonomic WMM in presence of obstacle in which a complex path is generated but there is no singularity in robot configuration. Some examples of occurring singular configuration in final point and moving boundary condition is also presented. The results show that flexibility of the joints near to singular configuration normalizes the sudden movement and jerk implied to actuators. That is why using a rotational spring with a low stiffness coefficient could be helpful to decrease the high jerk and increase the maximum allowable load in mobile robots.

  12. Analysis of the Stringer-to-Cross-Beam Riveted Joints Behaviour

    Directory of Open Access Journals (Sweden)

    Vičan Josef


    Full Text Available The main aim of the paper is to present results of the numerical and experimental studies related to the analysis of the real stiffness of the stringer-to-cross-beam connection in order to avoid approximation of this joint by means of complicated 2D modelling and to use simplified 1D model for global analyses of bridges with open bridge decks.

  13. Interventions for increasing ankle joint dorsiflexion: a systematic review and meta-analysis (United States)


    Background Ankle joint equinus, or restricted dorsiflexion range of motion (ROM), has been linked to a range of pathologies of relevance to clinical practitioners. This systematic review and meta-analysis investigated the effects of conservative interventions on ankle joint ROM in healthy individuals and athletic populations. Methods Keyword searches of Embase, Medline, Cochrane and CINAHL databases were performed with the final search being run in August 2013. Studies were eligible for inclusion if they assessed the effect of a non-surgical intervention on ankle joint dorsiflexion in healthy populations. Studies were quality rated using a standard quality assessment scale. Standardised mean differences (SMDs) and 95% confidence intervals (CIs) were calculated and results were pooled where study methods were homogenous. Results Twenty-three studies met eligibility criteria, with a total of 734 study participants. Results suggest that there is some evidence to support the efficacy of static stretching alone (SMDs: range 0.70 to 1.69) and static stretching in combination with ultrasound (SMDs: range 0.91 to 0.95), diathermy (SMD 1.12), diathermy and ice (SMD 1.16), heel raise exercises (SMDs: range 0.70 to 0.77), superficial moist heat (SMDs: range 0.65 to 0.84) and warm up (SMD 0.87) in improving ankle joint dorsiflexion ROM. Conclusions Some evidence exists to support the efficacy of stretching alone and stretching in combination with other therapies in increasing ankle joint ROM in healthy individuals. There is a paucity of quality evidence to support the efficacy of other non-surgical interventions, thus further research in this area is warranted. PMID:24225348

  14. Temperature and Humidity Profiles in the TqJoint Data Group of AIRS Version 6 Product for the Climate Model Evaluation (United States)

    Ding, Feng; Fang, Fan; Hearty, Thomas J.; Theobald, Michael; Vollmer, Bruce; Lynnes, Christopher


    The Atmospheric Infrared Sounder (AIRS) mission is entering its 13th year of global observations of the atmospheric state, including temperature and humidity profiles, outgoing long-wave radiation, cloud properties, and trace gases. Thus AIRS data have been widely used, among other things, for short-term climate research and observational component for model evaluation. One instance is the fifth phase of the Coupled Model Intercomparison Project (CMIP5) which uses AIRS version 5 data in the climate model evaluation. The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) is the home of processing, archiving, and distribution services for data from the AIRS mission. The GES DISC, in collaboration with the AIRS Project, released data from the version 6 algorithm in early 2013. The new algorithm represents a significant improvement over previous versions in terms of greater stability, yield, and quality of products. The ongoing Earth System Grid for next generation climate model research project, a collaborative effort of GES DISC and NASA JPL, will bring temperature and humidity profiles from AIRS version 6. The AIRS version 6 product adds a new "TqJoint" data group, which contains data for a common set of observations across water vapor and temperature at all atmospheric levels and is suitable for climate process studies. How different may the monthly temperature and humidity profiles in "TqJoint" group be from the "Standard" group where temperature and water vapor are not always valid at the same time? This study aims to answer the question by comprehensively comparing the temperature and humidity profiles from the "TqJoint" group and the "Standard" group. The comparison includes mean differences at different levels globally and over land and ocean. We are also working on examining the sampling differences between the "TqJoint" and "Standard" group using MERRA data.

  15. [Correlation analysis on the disorders of patella-femoral joint and torsional deformity of tibia]. (United States)

    Sun, Zhen-Jie; Yuan, Yi; Liu, Rui-Bo


    tibia is always accompanied by instability of patella-femoral joint,especially under the dynamic condition, thus causing PFDA. It can not only provide arrangement information and degenerative condition of patella-femoral joint,but also provide guidance through the analysis on the relationship for better clinical prevention and early treatment of degenerative bone and joint disease.

  16. Joint influence of temperature and ions of metals on level of activity alkaline phosphatase the mucous membrane of intestines beluga, the starlet and their hybrid

    Directory of Open Access Journals (Sweden)

    D. A. Bednyakov


    Full Text Available In work joint influence of ions of bivalent metals (Mn, Fe, Co, Ni, Cu and Zn and temperatures on level of activity alkaline phosphatase mucous membrane beluga, starlet and their hybrid is shown. Dependence of response of enzyme on action of ions of metals according to their position in a periodic table of chemical elements is shown. The given dependence remains and at temperature change incubation, only at low temperatures the activating effect of metals being in the period beginning is maximum, and at high, is maximum inhibiting effect of metals being in the period end.

  17. Three Groups in the 28 Joints for Rheumatoid Arthritis Synovitis – Analysis Using More than 17,000 Assessments in the KURAMA Database (United States)

    Terao, Chikashi; Hashimoto, Motomu; Yamamoto, Keiichi; Murakami, Kosaku; Ohmura, Koichiro; Nakashima, Ran; Yamakawa, Noriyuki; Yoshifuji, Hajime; Yukawa, Naoichiro; Kawabata, Daisuke; Usui, Takashi; Yoshitomi, Hiroyuki; Furu, Moritoshi; Yamada, Ryo; Matsuda, Fumihiko; Ito, Hiromu; Fujii, Takao; Mimori, Tsuneyo


    Rheumatoid arthritis (RA) is a joint-destructive autoimmune disease. Three composite indices evaluating the same 28 joints are commonly used for the evaluation of RA activity. However, the relationship between, and the frequency of, the joint involvements are still not fully understood. Here, we obtained and analyzed 17,311 assessments for 28 joints in 1,314 patients with RA from 2005 to 2011 from electronic clinical chart templates stored in the KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) database. Affected rates for swelling and tenderness were assessed for each of the 28 joints and compared between two different sets of RA patients. Correlations of joint symptoms were analyzed for swellings and tenderness using kappa coefficient and eigen vectors by principal component analysis. As a result, we found that joint affected rates greatly varied from joint to joint both for tenderness and swelling for the two sets. Right wrist joint is the most affected joint of the 28 joints. Tenderness and swellings are well correlated in the same joints except for the shoulder joints. Patients with RA tended to demonstrate right-dominant joint involvement and joint destruction. We also found that RA synovitis could be classified into three categories of joints in the correlation analyses: large joints with wrist joints, PIP joints, and MCP joints. Clustering analysis based on distribution of synovitis revealed that patients with RA could be classified into six subgroups. We confirmed the symmetric joint involvement in RA. Our results suggested that RA synovitis can be classified into subgroups and that several different mechanisms may underlie the pathophysiology in RA synovitis. PMID:23555018

  18. Analysis of Interrelationships among Voluntary and Prosthetic Leg Joint Parameters Using Cyclograms

    Directory of Open Access Journals (Sweden)

    Nur Azah Hamzaid


    Full Text Available The walking mechanism of a prosthetic leg user is a tightly coordinated movement of several joints and limb segments. The interaction among the voluntary and mechanical joints and segments requires particular biomechanical insight. This study aims to analyze the inter-relationship between amputees' voluntary and mechanical coupled leg joints variables using cyclograms. From this analysis, the critical gait parameters in each gait phase were determined and analyzed if they contribute to a better powered prosthetic knee control design. To develop the cyclogram model, 20 healthy able-bodied subjects and 25 prosthesis and orthosis users (10 transtibial amputees, 5 transfemoral amputees, and 10 different pathological profiles of orthosis users walked at their comfortable speed in a 3D motion analysis lab setting. The gait parameters (i.e., angle, moment and power for the ankle, knee and hip joints were coupled to form 36 cyclograms relationship. The model was validated by quantifying the gait disparities of all the pathological walking by analyzing each cyclograms pairs using feed-forward neural network with backpropagation. Subsequently, the cyclogram pairs that contributed to the highest gait disparity of each gait phase were manipulated by replacing it with normal values and re-analyzed. The manipulated cyclograms relationship that showed highest improvement in terms of gait disparity calculation suggested that they are the most dominant parameters in powered-knee control. In case of transfemoral amputee walking, it was identified using this approach that at each gait sub-phase, the knee variables most responsible for closest to normal walking were: knee power during loading response and mid-stance, knee moment and knee angle during terminal stance phase, knee angle and knee power during pre-swing, knee angle at initial swing, and knee power at terminal swing. No variable was dominant during mid-swing phase implying natural pendulum effect of the

  19. Biomechanical analysis of acromioclavicular joint dislocation treated with clavicle hook plates in different lengths. (United States)

    Shih, Cheng-Min; Huang, Kui-Chou; Pan, Chien-Chou; Lee, Cheng-Hung; Su, Kuo-Chih


    Clavicle hook plates are frequently used in clinical orthopaedics to treat acromioclavicular joint dislocation. However, patients often exhibit acromion osteolysis and per-implant fracture after undergoing hook plate fixation. With the intent of avoiding future complications or fixation failure after clavicle hook plate fixation, we used finite element analysis (FEA) to investigate the biomechanics of clavicle hook plates of different materials and sizes when used in treating acromioclavicular joint dislocation. Using finite element analysis, this study constructed a model comprising four parts: clavicle, acromion, clavicle hook plate and screws, and used the model to simulate implanting different types of clavicle hook plates in patients with acromioclavicular joint dislocation. Then, the biomechanics of stainless steel and titanium alloy clavicle hook plates containing either six or eight screw holes were investigated. The results indicated that using a longer clavicle hook plate decreased the stress value in the clavicle, and mitigated the force that clavicle hook plates exert on the acromion. Using a clavicle hook plate material characterized by a smaller Young's modulus caused a slight increase in the stress on the clavicle. However, the external force the material imposed on the acromion was less than the force exerted on the clavicle. The findings of this study can serve as a reference to help orthopaedic surgeons select clavicle hook plates.

  20. Variability and similarity of gait as evaluated by joint angles: implications for forensic gait analysis. (United States)

    Yang, Sylvia X M; Larsen, Peter K; Alkjær, Tine; Simonsen, Erik B; Lynnerup, Niels


    Closed-circuit television (CCTV) footage is used in criminal investigations to compare perpetrators with suspects. Usually, incomplete gait cycles are collected, making evidential gait analysis challenging. This study aimed to analyze the discriminatory power of joint angles throughout a gait cycle. Six sets from 12 men were collected. For each man, a variability range VR (mean ± 1SD) of a specific joint angle at a specific time point (a gait cycle was 100 time points) was calculated. In turn, each individual was compared with the 11 others, and whenever 1 of these 11 had a value within this individual’s VR, it counted as positive. By adding the positives throughout the gait cycle, we created simple bar graphs; tall bars indicated a small discriminatory power, short bars indicated a larger one. The highest discriminatory power was at time points 60–80 in the gait cycle. We show how our data can assess gait data from an actual case.

  1. Cosmological constraints from a joint analysis of cosmic growth and expansion (United States)

    Moresco, M.; Marulli, F.


    Combining measurements on the expansion history of the Universe and on the growth rate of cosmic structures is key to discriminate between alternative cosmological frameworks and to test gravity. Recently, Linder proposed a new diagram to investigate the joint evolutionary track of these two quantities. In this letter, we collect the most recent cosmic growth and expansion rate data sets to provide the state-of-the-art observational constraints on this diagram. By performing a joint statistical analysis of both probes, we test the standard Λcold dark matter model, confirming a mild tension between cosmic microwave background predictions from Planck mission and cosmic growth measurements at low redshift (z generation dark-energy mission forecasts, we show that growth rate constraints at z > 1 will be crucial to discriminate between alternative models.

  2. Fatigue Reliability Analysis of 6156-T6 Riveted Joints based on Detail Fatigue Rating (United States)

    Chen, An; Yang, Jun; Zhang, Kan; Zhang, Haiying


    The fatigue behavior of two kinds of riveted joints 6156-T6 aluminum alloy structures was experimentally investigated. The detail fatigue rating (DFR) values of 6156-T6 is calculated based on statistical analysis of fatigue tests. The fatigue crack initiation and propagation behavior are examined using scanning electron microscopy. The results show that DFR value of 6156-T6 aluminum alloy with riveted lap joints is 97.81MPa, and the DFR value of rivet-filled countersink hole structure is 168.39MPa. The crack initiation sites occurred at the vicinity of the fastener hole in all specimens. The fatigue striations were uniformly spaced in the region of stable crack growth.

  3. On joint diagonalization of cumulant matrices for independent component analysis of MRS and EEG signals. (United States)

    Albera, Laurent; Kachenoura, Amar; Wendling, Fabrice; Senhadji, Lotfi; Merlet, Isabelle


    An extension of the original implementation of JADE, named eJADE((1)) hereafter, was proposed in 2001 to perform independent component analysis for any combination of statistical orders greater than or equal to three. More precisely, eJADE((1)) relies on the joint diagonalization of a set of several cumulant matrices corresponding to different matrix slices of one or several higher order cumulant tensors. An efficient way, without lose of statistical information, of reducing the number of third and fourth order cumulant matrices to be jointly diagonalized is proposed in this paper. The resulting approach, named eJADE(3,4)((2)), can be interpreted as an improvement of the eJADE(3,4)((1)) method. A performance comparison with classical methods is conducted in the context of MRS and EEG signals showing the good behavior of our technique.

  4. Temperature analysis over southwest Iran: trends and projections (United States)

    Zarenistanak, Mohammad; Dhorde, Amit G.; Kripalani, R. H.


    The present study intends to show the effect of climate change on trends and patterns of temperature over the southwestern part of Iran. The research has been divided into two parts. The first part consists of an analysis of the temperature trends of mean temperature (TM), maximum temperature (TMAX), and minimum temperature (TMIN) over 39 stations in the study region for the period 1950-2007. The trends in these parameters were detected by linear regression, and significance was tested by t test. Mann-Kendall rank test (MK test) was also employed to confirm the results. The second part of the research involved future projection of temperature based on four models. The models used were Centre National de Recherches Meteorologiques, European Center Hamburg Model, Model for Interdisciplinary Research on Climate, and UK Meteorological Office. Temperature projections were done under B1 and A1B emissions scenarios. The analysis of temperature trends revealed a significant increase during summer and spring seasons. TMAX was stable than TMIN and TM, and winter was stable as compared with summer, spring, and autumn seasons. Results of modeling showed that temperature may increase between 1.69 and 6.88 °C by 2100 in the study area. Summer temperatures may increase with higher rates than spring, winter, and autumn temperatures.

  5. Analysis of 2-d ultrasound cardiac strain imaging using joint probability density functions. (United States)

    Ma, Chi; Varghese, Tomy


    Ultrasound frame rates play a key role for accurate cardiac deformation tracking. Insufficient frame rates lead to an increase in signal de-correlation artifacts resulting in erroneous displacement and strain estimation. Joint probability density distributions generated from estimated axial strain and its associated signal-to-noise ratio provide a useful approach to assess the minimum frame rate requirements. Previous reports have demonstrated that bi-modal distributions in the joint probability density indicate inaccurate strain estimation over a cardiac cycle. In this study, we utilize similar analysis to evaluate a 2-D multi-level displacement tracking and strain estimation algorithm for cardiac strain imaging. The effect of different frame rates, final kernel dimensions and a comparison of radio frequency and envelope based processing are evaluated using echo signals derived from a 3-D finite element cardiac model and five healthy volunteers. Cardiac simulation model analysis demonstrates that the minimum frame rates required to obtain accurate joint probability distributions for the signal-to-noise ratio and strain, for a final kernel dimension of 1 λ by 3 A-lines, was around 42 Hz for radio frequency signals. On the other hand, even a frame rate of 250 Hz with envelope signals did not replicate the ideal joint probability distribution. For the volunteer study, clinical data was acquired only at a 34 Hz frame rate, which appears to be sufficient for radio frequency analysis. We also show that an increase in the final kernel dimensions significantly affect the strain probability distribution and joint probability density function generated, with a smaller effect on the variation in the accumulated mean strain estimated over a cardiac cycle. Our results demonstrate that radio frequency frame rates currently achievable on clinical cardiac ultrasound systems are sufficient for accurate analysis of the strain probability distribution, when a multi-level 2-D

  6. Gait analysis in rats with single joint inflammation: influence of experimental factors.

    Directory of Open Access Journals (Sweden)

    Kristina Ängeby Möller

    Full Text Available Disability and movement-related pain are major symptoms of joint disease, motivating the development of methods to quantify motor behaviour in rodent joint pain models. We used observational scoring and automated methods to compare weight bearing during locomotion and during standing after single joint inflammation induced by Freund's complete adjuvant (0.12-8.0 mg/mL or carrageenan (0.47-30 mg/mL. Automated gait analysis was based on video capture of prints generated by light projected into the long edge of the floor of a walkway, producing an illuminated image of the contact area of each paw with light intensity reflecting the contact pressure. Weight bearing was calculated as an area-integrated paw pressure, that is, the light intensity of all pixels activated during the contact phase of a paw placement. Automated static weight bearing was measured with the Incapacitance tester. Pharmacological sensitivity of weight-bearing during locomotion was tested in carrageenan-induced monoarthritis by administration of the commonly used analgesics diclofenac, ibuprofen, and naproxen, as well as oxycodone and paracetamol. Observational scoring and automated quantification yielded similar results. We found that the window between control rats and monoarthritic rats was greater during locomotion. The response was more pronounced for inflammation in the ankle as compared to the knee, suggesting a methodological advantage of using this injection site. The effects of both Freund's complete adjuvant and carrageenan were concentration related, but Freund's incomplete adjuvant was found to be as effective as lower, commonly used concentrations of the complete adjuvant. The results show that gait analysis can be an effective method to quantify behavioural effects of single joint inflammation in the rat, sensitive to analgesic treatment.

  7. Analysis of features of stainless steels in dissimilar welded joints in chloride inducted corrosion (United States)

    Topolska, S.; Łabanowski, J.


    Stainless steels of femtic-austenitic microstructure that means the duplex Cr-Ni-Mo steels, in comparison with austenitic steel includes less expensive nickel and has much better mechanical properties with good formability and corrosion resistance, even in environments containing chloride ions. Similar share of high chromium ferrite and austenite, which is characterized by high ductility, determines that the duplex steels have good crack resistance at temperatures up to approximately -40°C. The steels containing approximately 22% Cr, 5% Ni, 3% Mo and 0.2% N crystallizes as a solid solution δ, partially transforming from the temperature of about 1200°C to 850°C into the phase α. The stable structure of considered steels, at temperatures above 850°C, is ferrite, and at lower temperatures the mixture of phase γ+α +σ. The two-phase structure α+γ the duplex steel obtains after hyperquenching at the temperature of stability of the mixture of α+γ phases, and the share of the phases depends on the hyper quenching attributes. Hyperquenching in water, with a temperature close to 1200°C, ensures the instance in the microstructure of the steel a large share of ferrite and a small share of the high chromium austenite. This causes the increase of strength properties and reducing the plasticity of the steel and its resistance ability to cracking and corrosion. Slower cooling from the mentioned temperature, for example in the air, enables the partial transformation of the a phase into the γ one (α → γ) and increasing the share of austenite in the steel structure. It leads to improvement of plasticity properties. In the paper are presented the results of investigations of heteronymous welded joints of duplex steel and austenitic one. The results include the relation between the chemical composition of steels and their weldability.

  8. Microbiota analysis to reveal temperature abuse of fresh pork

    DEFF Research Database (Denmark)

    Buschhardt, Tasja; Bahl, Martin Iain; Hansen, Tina Beck

    Violations of temperature regulations in the meat chain may affect meat safety. Methods are lacking to estimate whether meat has been subjected to temperature abuse. Exposure to too high temperatures may lead to systematic changes in the diverse bacterial communities of fresh meat. We investigated...... whether temperature induced changes in the community composition on fresh meat surfaces can reflect the temperature-history (combination of time and temperature). Sterile pieces of pork were inoculated with a carcass swab homogenate, to which Salmonella was added. Changes in the meat microbiota were...... was dominated by Pseudomonas only. We also showed that the initial community affects subsequent changes during storage. The results suggest that principal coordinate analysis of beta diversity could be a useful tool to reveal temperature abused meat. Sequence data and culturing data revealed a strong positive...

  9. Determination of temperature of moving surface by sensitivity analysis

    CERN Document Server

    Farhanieh, B


    In this paper sensitivity analysis in inverse problem solutions is employed to estimate the temperature of a moving surface. Moving finite element method is used for spatial discretization. Time derivatives are approximated using Crank-Nicklson method. The accuracy of the solution is assessed by simulation method. The convergence domain is investigated for the determination of the temperature of a solid fuel.

  10. Experimental research and statistic analysis of polymer composite adhesive joints strength (United States)

    Rudawska, Anna; Miturska, Izabela; Szabelski, Jakub; Skoczylas, Agnieszka; Droździel, Paweł; Bociąga, Elżbieta; Madleňák, Radovan; Kasperek, Dariusz


    The aim of this paper is to determine the effect of arrangement of fibreglass fabric plies in a polymer composite on adhesive joint strength. Based on the experimental results, the real effect of plies arrangement and their most favourable configuration with respect to strength is determined. The experiments were performed on 3 types of composites which had different fibre orientations. The composites had three plies of fabric. The plies arrangement in Composite I was unchanged, in Composite II the central ply had the 45° orientation, while in Composite III the outside ply (tangential to the adhesive layer) was oriented at 45°. Composite plates were first cut into smaller specimens and then adhesive-bonded in different combinations with Epidian 61/Z1/100:10 epoxy adhesive. After stabilizing, the single-lap adhesive joints were subjected to shear strength tests. It was noted that plies arrangement in composite materials affects the strength of adhesive joints made of these composites between the values of the strength of the confidence level of 0.95. The statistical analysis of the results also showed that there are no statistical significant differences in average values of surface free energy (0.95 confidence level).

  11. Concept for a fast analysis method of the energy dissipation at mechanical joints (United States)

    Wolf, Alexander; Brosius, Alexander


    When designing hybrid parts and structures one major challenge is the design, production and quality assessment of the joining points. While the polymeric composites themselves have excellent material properties, the necessary joints are often the weak link in assembled structures. This paper presents a method of measuring and analysing the energy dissipation at mechanical joining points of hybrid parts. A simplified model is applied based on the characteristic response to different excitation frequencies and amplitudes. The dissipation from damage is the result of relative moments between joining partners und damaged fibres within the composite, whereas the visco-elastic material behaviour causes the intrinsic dissipation. The ambition is to transfer these research findings to the characterisation of mechanical joints in order to quickly assess the general quality of the joint with this non-destructive testing method. The inherent challenge for realising this method is the correct interpretation of the measured energy dissipation and its attribution to either a bad joining point or intrinsic material properties. In this paper the authors present the concept for energy dissipation measurements at different joining points. By inverse analysis a simplified fast semi-analytical model will be developed that allows for a quick basic quality assessment of a given joining point.

  12. Static analysis of large-scale multibody system using joint coordinates and spatial algebra operator. (United States)

    Omar, Mohamed A


    Initial transient oscillations inhibited in the dynamic simulations responses of multibody systems can lead to inaccurate results, unrealistic load prediction, or simulation failure. These transients could result from incompatible initial conditions, initial constraints violation, and inadequate kinematic assembly. Performing static equilibrium analysis before the dynamic simulation can eliminate these transients and lead to stable simulation. Most exiting multibody formulations determine the static equilibrium position by minimizing the system potential energy. This paper presents a new general purpose approach for solving the static equilibrium in large-scale articulated multibody. The proposed approach introduces an energy drainage mechanism based on Baumgarte constraint stabilization approach to determine the static equilibrium position. The spatial algebra operator is used to express the kinematic and dynamic equations of the closed-loop multibody system. The proposed multibody system formulation utilizes the joint coordinates and modal elastic coordinates as the system generalized coordinates. The recursive nonlinear equations of motion are formulated using the Cartesian coordinates and the joint coordinates to form an augmented set of differential algebraic equations. Then system connectivity matrix is derived from the system topological relations and used to project the Cartesian quantities into the joint subspace leading to minimum set of differential equations.

  13. NOAA High-Resolution Sea Surface Temperature (SST) Analysis Products (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archive covers two high resolution sea surface temperature (SST) analysis products developed using an optimum interpolation (OI) technique. The analyses have a...

  14. Innovative Instrumentation and Analysis of the Temperature Measurement for High Temperature Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee


    The objectives of this project during this semi-annual reporting period are to test the effects of coating layer of the thermal couple on the temperature measurement and to screen out the significant factors affecting the temperature reading under different operational conditions. The systematic tests of the gasifier simulator on the high velocity oxygen fuel (HVOF) spray coated thermal couples were completed in this reporting period. The comparison tests of coated and uncoated thermal couples were conducted under various operational conditions. The temperature changes were recorded and the temperature differences were calculated to describe the thermal spray coating effect on the thermal couples. To record the temperature data accurately, the computerized data acquisition system (DAS) was adopted to the temperature reading. The DAS could record the data with the accuracy of 0.1 C and the recording parameters are configurable. In these experiments, DAS was set as reading one data for every one (1) minute. The operational conditions are the combination of three parameters: air flow rate, water/ammonia flow rate and the amount of fine dust particles. The results from the temperature readings show the temperature of uncoated thermal couple is uniformly higher than that of coated thermal couple for each operational condition. Analysis of Variances (ANOVA) was computed based on the results from systematic tests to screen out the significant factors and/or interactions. The temperature difference was used as dependent variable and three operational parameters (i.e. air flow rate, water/ammonia flow rate and amount of fine dust particle) were used as independent factors. The ANOVA results show that the operational parameters are not the statistically significant factors affecting the temperature readings which indicate that the coated thermal couple could be applied to temperature measurement in gasifier. The actual temperature reading with the coated thermal couple in

  15. Evaluation on joint toxicity of chlorinated anilines and cadmium to Photobacterium phosphoreum and QSAR analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hao, E-mail: [School of Life and Chemistry, Jiangsu Second Normal University, Nanjing, Jiangsu 210013 (China); Wang, Chao; Shi, Jiaqi [State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu 210023 (China); Chen, Lei [School of Life and Chemistry, Jiangsu Second Normal University, Nanjing, Jiangsu 210013 (China)


    Highlights: • Cd has different effects on joint toxicity when in different concentrations. • The toxicity of most binary mixtures decreases when Cd concentration rises. • Different QSAR models are developed to predict the joint toxicity. • Descriptors in QSARs can help to elucidate the joint toxicity mechanism. • Van der Waals’ force or complexation may reduce the toxicity of mixtures. - Abstract: The individual IC{sub 50} (the concentrations causing a 50% inhibition of bioluminescence after 15 min exposure) of cadmium ion (Cd) and nine chlorinated anilines to Photobacterium phosphoreum (P. phosphoreum) were determined. In order to evaluate the combined effects of the nine chlorinated anilines and Cd, the toxicities of chlorinated anilines combined with different concentrations of Cd were determined, respectively. The results showed that the number of chlorinated anilines manifesting synergy with Cd decreased with the increasing Cd concentration, and the number manifesting antagonism decreased firstly and then increased. The joint toxicity of mixtures at low Cd concentration was weaker than that of most binary mixtures when combined with Cd at medium and high concentrations as indicated by TU{sub Total}. QSAR analysis showed that the single toxicity of chlorinated anilines was related to the energy of the lowest unoccupied molecular orbital (E{sub LUMO}). When combined with different concentrations of Cd, the toxicity was related to the energy difference (E{sub HOMO} − E{sub LUMO}) with different coefficients. Van der Waals’ force or the complexation between chlorinated anilines and Cd had an impact on the toxicity of combined systems, which could account for QSAR models with different physico-chemical descriptors.

  16. Analysis of the Seismic Performance of a Rock Joint with a Modified Continuously Yielding Model (United States)

    Cui, Zhen; Sheng, Qian; Leng, Xianlun; Ma, Yalina


    The problem of seismic wave transmission at a rock joint is a critical issue for aseismic affairs of underground rock engineering. Little attention has been given to the normal cyclic loading behavior of a joint during wave propagation. This paper introduces a modification to Cundall's continuously yielding (CY) model. The original normal behavior of the CY model is upgraded by adding the capacity to account for sophisticated characteristics during normal cyclic loading. The proposed modified-CY (M-CY) model is verified through comparison with existing experimental data. The effects of various parameters in this M-CY model are discussed, indicating that the M-CY model is capable of fitting realistic test data. Subsequently, P-wave transmission across a M-CY joint is numerically performed and evaluated. The results show that the M-CY model exhibits more transmission and consequently less reflection than the linear model as the velocity magnitude of an incident impulse approaches its peak value. Furthermore, the compatibility of the joint under an incident P-wave can be revealed by the M-CY model. The seismic stability of the tailrace tunnel of the Baihetan Hydropower Plant, which is controlled by a large fault, is studied as an engineering application of the proposed model. Seismic analysis suggests that the tunnel's main failure mode under an earthquake would be shear slip at the intersection of the tunnel ceiling and fault. A comparison between the proposed model and original CY model illustrates that the original model would give a failure mode that overestimates the fault opening during the earthquake.

  17. Curie temperature determination via thermogravimetric and continuous wavelet transformation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hasier, John; Nash, Philip [Thermal Processing Technology Center, IIT, Chicago, IL (United States); Riolo, Maria Annichia [University of Michigan, Center for the Study of Complex Systems, Ann Arbor, MI (United States)


    A cost effective method for conversion of a vertical tube thermogravimetric analysis system into a magnetic balance capable of measuring Curie Temperatures is presented. Reference and preliminary experimental data generated using this system is analyzed via a general-purpose wavelet based Curie point edge detection technique allowing for enhanced speed, ease and repeatability of magnetic balance data analysis. The Curie temperatures for a number of Heusler compounds are reported. (orig.)


    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee


    During this reporting period, the literature survey including the gasifier temperature measurement literature, the ultrasonic application and its background study in cleaning application, and spray coating process are completed. The gasifier simulator (cold model) testing has been successfully conducted. Four factors (blower voltage, ultrasonic application, injection time intervals, particle weight) were considered as significant factors that affect the temperature measurement. The Analysis of Variance (ANOVA) was applied to analyze the test data. The analysis shows that all four factors are significant to the temperature measurements in the gasifier simulator (cold model). The regression analysis for the case with the normalized room temperature shows that linear model fits the temperature data with 82% accuracy (18% error). The regression analysis for the case without the normalized room temperature shows 72.5% accuracy (27.5% error). The nonlinear regression analysis indicates a better fit than that of the linear regression. The nonlinear regression model's accuracy is 88.7% (11.3% error) for normalized room temperature case, which is better than the linear regression analysis. The hot model thermocouple sleeve design and fabrication are completed. The gasifier simulator (hot model) design and the fabrication are completed. The system tests of the gasifier simulator (hot model) have been conducted and some modifications have been made. Based on the system tests and results analysis, the gasifier simulator (hot model) has met the proposed design requirement and the ready for system test. The ultrasonic cleaning method is under evaluation and will be further studied for the gasifier simulator (hot model) application. The progress of this project has been on schedule.

  19. Asymptotic Sampling for Reliability Analysis of Adhesive Bonded Stepped Lap Composite Joints

    DEFF Research Database (Denmark)

    Kimiaeifar, Amin; Lund, Erik; Thomsen, Ole Thybo


    Reliability analysis coupled with finite element analysis (FEA) of composite structures is computationally very demanding and requires a large number of simulations to achieve an accurate prediction of the probability of failure with a small standard error. In this paper Asymptotic Sampling, which...... is a promising and time efficient tool to calculate the probability of failure, is utilized, and a probabilistic model for the reliability analysis of adhesive bonded stepped lap composite joints, representative for the main laminate in a wind turbine blade subjected to static flapwise bending load, is presented....... Three dimensional (3D) FEA is used for the structural analysis together with a design equation that is associated with a deterministic code-based design equation where reliability is secured by partial safety factors. The Tsai-Wu and the maximum principal stress failure criteria are used to predict...

  20. Mechanical Properties of WE43 Magnesium Alloy Joint at Elevated Temperature / Właściwości Mechaniczne Złączy Ze Stopu Magnezu WE43 W Podwyższonej Temperaturze

    Directory of Open Access Journals (Sweden)

    Turowska A.


    Full Text Available The WE43 cast magnesium alloy, containing yttrium and rare earth elements, remains stable at temperatures up to 300°C, according to the manufacturer, and therefore it is considered for a possible application in the aerospace and automotive. Usually, it is cast gravitationally into sand moulds and used for large-size castings that find application in the aerospace industry. After the casting process any possible defects that might appear in the casting are repaired with the application of welding techniques. These techniques also find application in renovation of the used cast elements and in the process of joining the cast parts into complex structures. An important factor determining the validity of the application of welding techniques for repairing or joining cast magnesium alloys is the structural stability and the stability of the properties of the joint in operating conditions. In the literature of the subject are information on the properties of the WE43 alloy or an impact of heat treatment on the structure and properties of the alloy, however, there is a lack of information concerning the welded joints produced from this alloy. This paper has been focused on the analysis the microstructure of the welded joints and their mechanical properties at elevated temperatures. To do this, tensile tests at temperatures ranging from 20°C to 300°C were performed. The tests showed, that up to the temperature of 150°C the crack occurred in the base material, whereas above this temperature level the rapture occurred within the weld. The loss of cohesion resulted from the nucleation of voids on grain boundaries and their formation into the main crack. The strength of the joints ranged from 150 MPa to 235 MPa, i.e. around 90 % of strength of the WE43 alloy after heat treatment (T6. Also performed a profilometric examination was to establish the shape of the fracture and to analyze how the temperature affected a contribution of phases in the process of

  1. Therapist Attitudes Towards Evidence-Based Practice: A Joint Factor Analysis. (United States)

    Burgess, Alexandra M; Okamura, Kelsie H; Izmirian, Sonia C; Higa-McMillan, Charmaine K; Shimabukuro, Scott; Nakamura, Brad J


    Despite the accumulated research support for the use of evidence-based practices (EBPs) with youth, these treatment approaches remain underutilized in community settings. Therapist attitudes towards EBPs play a pivotal role in their adoption and implementation of these practices. The present investigation employs joint exploratory factor analysis to evaluate the structure of two measures of therapist attitudes, the Evidence-Based Practices Attitudes Scale and the Modified Practice Attitude Scale. Results suggest three factors including (a) importance of clinical experience over EBPs, (b) clinician openness to change, and (c) problems with EBPs. Recommendations are provided for future evaluation of therapist attitudes and associated characteristics.

  2. Cross View Gait Recognition Using Joint-Direct Linear Discriminant Analysis. (United States)

    Portillo-Portillo, Jose; Leyva, Roberto; Sanchez, Victor; Sanchez-Perez, Gabriel; Perez-Meana, Hector; Olivares-Mercado, Jesus; Toscano-Medina, Karina; Nakano-Miyatake, Mariko


    This paper proposes a view-invariant gait recognition framework that employs a unique view invariant model that profits from the dimensionality reduction provided by Direct Linear Discriminant Analysis (DLDA). The framework, which employs gait energy images (GEIs), creates a single joint model that accurately classifies GEIs captured at different angles. Moreover, the proposed framework also helps to reduce the under-sampling problem (USP) that usually appears when the number of training samples is much smaller than the dimension of the feature space. Evaluation experiments compare the proposed framework's computational complexity and recognition accuracy against those of other view-invariant methods. Results show improvements in both computational complexity and recognition accuracy.

  3. How to apply the dependence structure analysis to extreme temperature and precipitation for disaster risk assessment (United States)

    Feng, Jieling; Li, Ning; Zhang, Zhengtao; Chen, Xi


    IPCC reports that a changing climate can affect the frequency and the intensity of extreme events. However, the extremes appear in the tail of the probability distribution. In order to know the relationship between extreme events in the tail of temperature and precipitation, an important but previously unobserved dependence structure is analyzed in this paper. Here, we examine the dependence structure by building a bivariate joint of Gumbel copula model for temperature and precipitation using monthly average temperature (T) and monthly precipitation (P) data from Beijing station in China covering a period of 1951-2015 and find the dependence structure can be divided into two sections, they are the middle part and the upper tail. We show that T and P have a strong positive correlation in the high tail section (T > 25.85 °C and P > 171.1 mm) (=0.66, p < 0.01) while they do not demonstrate the same relation in the other section, which suggests that the identification of a strong influence of T on extreme P needs help from the dependence structure analysis. We also find that in the high tail section, every 1 °C increase in T is associated with 73.45 mm increase in P. Our results suggested that extreme precipitation fluctuations by changes in temperature will allow the data dependence structure to be included in extreme affect for the disaster risk assessment under future climate change scenarios. Copula bivariate jointed probability distribution is useful to the dependence structure analysis.

  4. Finite element modelling for thermal analysis of stud-to-plate laser brazing for a dissimilar metal joint

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jun Soo; Kim, Jong Min [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)


    A finite element model was developed for the thermal analysis of a stud-to-plate laser brazing joint, and the transient temperature fields were analysed by using a three-dimensional model. The finite element program ABAQUS, together with a few user subroutines, was employed to perform the numerical approximation. Temperature-dependent thermal properties, effect of latent heat, and the convection and radiative heat losses were considered. The brazing parts used were AISI 304 stainless steel stud and aluminium A1 5052 plate, and the brazing alloy 88 A1-12 Si was used as filler metal. A pseudo-TM{sub 01} mode of the cw CO{sub 2} laser beam was used as heat source, for which TM{sub 00} mode generated by beam oscillator was optically modulated using axicon lens. Re-location of the filler metal during the brazing process including its wetting and spreading was examined by using a high speed motion analyser, and the results were incorporated inn the FEM modelling for defining the solution domain and boundary conditions. The numerical results were obtained for typical process parameters, and were compared with experimental ones determined by using the infrared and thermocouple measurements. 11 figs., 30 refs. (Author).

  5. A new classification of hemiplegia gait patterns based on bicluster analysis of joint moments. (United States)

    Pauk, Jolanta; Minta-Bielecka, Katarzyna


    Hemiplegia is a paralysis on one side of the body resulting from disease or injury to the motor centers of the brain that may lead to difficulty in walking and problems in balance. A new methodology for hemiplegia gait patterns classification based on bicluster analysis, which aims to identify a group of patients with similar gait patterns, and verify if spatial-temporal gait parameters are correlated with the Barthel Index, has been proposed. Eighteen hemiplegia patients were recruited. Measurements included spatialtemporal gait parameters and joint moments. Gait data were measured using a motion tracking system and two force platforms. Bicluster analysis was used to classify the subjects' gait patterns. The relation between Barthel Index and spatial-temporal gait parameters was determined based on the Spearman correlation. A high correlation between spatial-temporal gait parameters and Barthel Index (r>0.5, p <0.05) was observed. Well-separated biclusters presenting similarity among the lower limb joints during the gait cycles were obtained from the data. Bicluster analysis can be useful for identifying patients with similar gait patterns. The relation between the gait patterns and the underlying impairments would allow clinicians to target rehabilitation strategies at the patient's individual needs.

  6. A New Material Model for 2D FE Analysis of Adhesively Bonded Composite Joints

    Directory of Open Access Journals (Sweden)

    Libin ZHAO


    Full Text Available Effective and convenient stress analysis techniques play important roles in the analysis and design of adhesively bonded composite joints. A new material model is presented at the level of composite ply according to the orthotropic elastic mechanics theory and plane strain assumption. The model proposed has the potential to reserve nature properties of laminates with ply-to-ply modeling. The equivalent engineering constants in the model are obtained only by the material properties of unidirectional composites. Based on commercial FE software ABAQUS, a 2D FE model of a single-lap adhesively bonded joint was established conveniently by using the new model without complex modeling process and much professional knowledge. Stress distributions in adhesive were compared with the numerical results by Tsai and Morton and interlaminar stresses between adhesive and adherents were compared with the results from a detailed 3D FE analysis. Good agreements in both cases verify the validity of the proposed model. DOI:

  7. Genetic association tests: a method for the joint analysis of family and case-control data

    Directory of Open Access Journals (Sweden)

    Gray-McGuire Courtney


    Full Text Available Abstract With the trend in molecular epidemiology towards both genome-wide association studies and complex modelling, the need for large sample sizes to detect small effects and to allow for the estimation of many parameters within a model continues to increase. Unfortunately, most methods of association analysis have been restricted to either a family-based or a case-control design, resulting in the lack of synthesis of data from multiple studies. Transmission disequilibrium-type methods for detecting linkage disequilibrium from family data were developed as an effective way of preventing the detection of association due to population stratification. Because these methods condition on parental genotype, however, they have precluded the joint analysis of family and case-control data, although methods for case-control data may not protect against population stratification and do not allow for familial correlations. We present here an extension of a family-based association analysis method for continuous traits that will simultaneously test for, and if necessary control for, population stratification. We further extend this method to analyse binary traits (and therefore family and case-control data together and accurately to estimate genetic effects in the population, even when using an ascertained family sample. Finally, we present the power of this binary extension for both family-only and joint family and case-control data, and demonstrate the accuracy of the association parameter and variance components in an ascertained family sample.

  8. A newly developed snow vehicle (SM100S) for Antarctica. Part 3: Low temperature toughness of the welded joints of the structural steel (United States)

    Sakui, Shin; Nakajima, Masashi


    For the purpose of developing a new snow vehicle (common use at temperature about -50 C) for the deep ice coring project at Dome Fuji, East Antarctica, the low temperature toughness of the welded joints of structural steel was investigated. It is empirically well known that in case of vehicles employed in a cold air temperature of about -50 C, the low temperature brittle fracture of the structural members does not take place, if one uses semi-killed or killed steel, for which 50 percent FATT's (fracture appearance transition temperature) of the Charpy impact test is about -50 C and Charpy impact values at -50 C are 20 to 29 J/sq cm. In the present report, the Charpy impact test has been performed for both single pass SMAW (shield metal arc welding) and CO2 arc welded joints of JIS (Japan Industrial Standards) steels of SS400, SL2N255, STPL380, and STPL450. The test results show that the JIS steels of SL2N255 and STPL450 can be used for the new vehicle, considering their toughness.

  9. Computed Tomographic Image Analysis Based on FEM Performance Comparison of Segmentation on Knee Joint Reconstruction

    Directory of Open Access Journals (Sweden)

    Seong-Wook Jang


    Full Text Available The demand for an accurate and accessible image segmentation to generate 3D models from CT scan data has been increasing as such models are required in many areas of orthopedics. In this paper, to find the optimal image segmentation to create a 3D model of the knee CT data, we compared and validated segmentation algorithms based on both objective comparisons and finite element (FE analysis. For comparison purposes, we used 1 model reconstructed in accordance with the instructions of a clinical professional and 3 models reconstructed using image processing algorithms (Sobel operator, Laplacian of Gaussian operator, and Canny edge detection. Comparison was performed by inspecting intermodel morphological deviations with the iterative closest point (ICP algorithm, and FE analysis was performed to examine the effects of the segmentation algorithm on the results of the knee joint movement analysis.


    Directory of Open Access Journals (Sweden)

    Marian Blaško


    Full Text Available Many metal parts in various applications are being replaced by plastic parts. There are several reasons for that depending on actual application - minimize part cost, enhance corrosion resistance, integrating more components into one part etc. Most important steps of metal to plastic conversion are material selection and design of plastic part. Plastic part has to withstand the same load as metal part. To fulfill this requirement fiber reinforced engineering plastics are often used. Also it is convenient to substitute heavy wall sections with ribbed structure to increase load-carrying ability of part and decrease cycle time, eliminate voids, sink marks etc. Mechanical properties of such part could be highly affected by fiber orientation. Results of fiber orientation from injection molding filling analysis can be used in stress analysis for better prediction of part response to mechanical load. Such coupled analysis is performed here in this case study on bolted flange joint.

  11. Finite element analysis of beam-to-column joints in steel frames under cyclic loading

    Directory of Open Access Journals (Sweden)

    Elsayed Mashaly


    Full Text Available The aim of this paper is to present a simple and accurate three-dimensional (3D finite element model (FE capable of predicting the actual behavior of beam-to-column joints in steel frames subjected to lateral loads. The software package ANSYS is used to model the joint. The bolted extended-end-plate connection was chosen as an important type of beam–column joints. The extended-end-plate connection is chosen for its complexity in the analysis and behavior due to the number of connection components and their inheritable non-linear behavior. Two experimental tests in the literature were chosen to verify the finite element model. The results of both the experimental and the proposed finite element were compared. One of these tests was monotonically loaded, whereas the second was cyclically loaded. The finite element model is improved to enhance the defects of the finite element model used. These defects are; the long time need for the analysis and the inability of the contact element type to follow the behavior of moment–rotation curve under cyclic loading. As a contact element, the surface-to-surface element is used instead of node-to-node element to enhance the model. The FE results show good correlation with the experimental one. An attempt to improve a new technique for modeling bolts is conducted. The results show that this technique is supposed to avoid the defects above, give much less elements number and less solution time than the other modeling techniques.

  12. Advanced energy analysis of high temperature fuel cell systems

    NARCIS (Netherlands)

    Kouffeld, R.W.J.; Veringa, H.J.; De Groot, A.

    In this thesis the performance of high temperature fuel cell systems is studied using a new method of exergy analysis. The thesis consists of three parts: ⢠In the first part a new analysis method is developed, which not only considers the total exergy losses in a unit operation, but which

  13. Advanced energy analysis of high temperature fuel cell systems

    NARCIS (Netherlands)

    De Groot, A.


    In this thesis the performance of high temperature fuel cell systems is studied using a new method of exergy analysis. The thesis consists of three parts: ⢠In the first part a new analysis method is developed, which not only considers the total exergy losses in a unit operation, but which

  14. Joint analysis of histopathology image features and gene expression in breast cancer. (United States)

    Popovici, Vlad; Budinská, Eva; Čápková, Lenka; Schwarz, Daniel; Dušek, Ladislav; Feit, Josef; Jaggi, Rolf


    Genomics and proteomics are nowadays the dominant techniques for novel biomarker discovery. However, histopathology images contain a wealth of information related to the tumor histology, morphology and tumor-host interactions that is not accessible through these techniques. Thus, integrating the histopathology images in the biomarker discovery workflow could potentially lead to the identification of new image-based biomarkers and the refinement or even replacement of the existing genomic and proteomic signatures. However, extracting meaningful and robust image features to be mined jointly with genomic (and clinical, etc.) data represents a real challenge due to the complexity of the images. We developed a framework for integrating the histopathology images in the biomarker discovery workflow based on the bag-of-features approach - a method that has the advantage of being assumption-free and data-driven. The images were reduced to a set of salient patterns and additional measurements of their spatial distribution, with the resulting features being directly used in a standard biomarker discovery application. We demonstrated this framework in a search for prognostic biomarkers in breast cancer which resulted in the identification of several prognostic image features and a promising multimodal (imaging and genomic) prognostic signature. The source code for the image analysis procedures is freely available. The framework proposed allows for a joint analysis of images and gene expression data. Its application to a set of breast cancer cases resulted in image-based and combined (image and genomic) prognostic scores for relapse-free survival.

  15. Social Media and Total Joint Arthroplasty: An Analysis of Patient Utilization on Instagram. (United States)

    Ramkumar, Prem N; Navarro, Sergio M; Haeberle, Heather S; Chughtai, Morad; Flynn, Megan E; Mont, Michael A


    The purpose of this study was to analyze the nature of shared content of total joint arthroplasty patients on Instagram. Specifically, we evaluated social media posts for: (1) perspective and timing; (2) tone; (3) focus (activities of daily living [ADLs], rehabilitation, return-to-work); and (4) the comparison between hip and knee arthroplasties. A search of the public Instagram domain was performed over a 6-month period. Total hip and knee arthroplasties (THA and TKA) were selected for the analysis using the following terms: "#totalhipreplacement," "#totalkneereplacement," and associated terms. 1287 individual public posts of human subjects were shared during the period. A categorical scoring system was utilized for media format (photo or video), time (preoperative, perioperative, or postoperative) period, tone (positive or negative), return-to-work, ADLs, rehabilitation, surgical site, radiograph image, satisfaction, and dissatisfaction. Ninety-one percent of the posts were shared during the postoperative period. Ninety-three percent of posts had a positive tone. Thirty-four percent of posts focused on both ADLs and 33.8% on rehabilitation. TKA patients shared more about their surgical site (14.5% vs 3.3%, P Instagram, arthroplasty patients did so with a positive tone, starting a week after surgery. TKA posts focused more on rehabilitation and wound healing than THA patients, whereas THA patients shared more posts on ADLs. The analysis of social media posts provides insight into what matters to patients after total joint arthroplasty. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Analysis and design of rolling-contact joints for evaluating bone plate performance. (United States)

    Slocum, Alexander H; Cervantes, Thomas M; Seldin, Edward B; Varanasi, Kripa K


    An apparatus for testing maxillofacial bone plates has been designed using a rolling contact joint. First, a free-body representation of the fracture fixation techniques utilizing bone plates is used to illustrate how rolling contact joints accurately simulate in vivo biomechanics. Next, a deterministic description of machine functional requirements is given, and is then used to drive the subsequent selection and design of machine elements. Hertz contact stress and fatigue analysis for two elements are used to ensure that the machine will both withstand loads required to deform different plates, and maintain a high cycle lifetime for testing large numbers of plates. Additionally, clinically relevant deformations are presented to illustrate how stiffness is affected after a deformation is applied, and to highlight improvements made by the machine over current testing standards, which do not adequately re-create in vivo loading conditions. The machine performed as expected and allowed for analysis of bone plates in both deformed and un-deformed configurations to be conducted. Data for deformation experiments is presented to show that the rolling-contact testing machine leads to improved loading configurations, and thus a more accurate description of plate performance. A machine for evaluation of maxillofacial bone plates has been designed, manufactured, and used to accurately simulate in vivo loading conditions to more effectively evaluate the performance of both new and existing bone plates. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

  17. Mechanical influences on morphogenesis of the knee joint revealed through morphological, molecular and computational analysis of immobilised embryos.

    Directory of Open Access Journals (Sweden)

    Karen A Roddy

    Full Text Available Very little is known about the regulation of morphogenesis in synovial joints. Mechanical forces generated from muscle contractions are required for normal development of several aspects of normal skeletogenesis. Here we show that biophysical stimuli generated by muscle contractions impact multiple events during chick knee joint morphogenesis influencing differential growth of the skeletal rudiment epiphyses and patterning of the emerging tissues in the joint interzone. Immobilisation of chick embryos was achieved through treatment with the neuromuscular blocking agent Decamethonium Bromide. The effects on development of the knee joint were examined using a combination of computational modelling to predict alterations in biophysical stimuli, detailed morphometric analysis of 3D digital representations, cell proliferation assays and in situ hybridisation to examine the expression of a selected panel of genes known to regulate joint development. This work revealed the precise changes to shape, particularly in the distal femur, that occur in an altered mechanical environment, corresponding to predicted changes in the spatial and dynamic patterns of mechanical stimuli and region specific changes in cell proliferation rates. In addition, we show altered patterning of the emerging tissues of the joint interzone with the loss of clearly defined and organised cell territories revealed by loss of characteristic interzone gene expression and abnormal expression of cartilage markers. This work shows that local dynamic patterns of biophysical stimuli generated from muscle contractions in the embryo act as a source of positional information guiding patterning and morphogenesis of the developing knee joint.


    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee


    The systematic tests of the gasifier simulator on the ultrasonic vibration application for cleaning method were completed in this reporting period. Within the systematic tests on the ultrasonic vibration application, the ambient temperature and high temperature status condition were tested separately. The sticky dirt on the thermocouple tip was simulated by the cement-covered layer on the thermocouple tip. At the ambient temperature status, four (4) factors were considered as the input factors affecting the response variable of peeling off rate. The input factors include the shape of the cement-covered layer (thickness and length), the ultrasonic vibration output power, and application time. At the high temperature tests, four (4) different environments were considered as the experimental parameters including air flow supply, water and air supply environment, water/air/fine dust particle supply, and air/water/ammonia/fine dust particle supply environment. The factorial design method was used in the experiment design with twelve (12) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the thickness and length of the cement-covered layer have the significant impact on the peeling off rate of ultrasonic vibration application at the ambient temperature environment. For the high temperature tests, the different environments do not seem to have significant impact on the temperature changes. These results may indicate that the ultrasonic vibration is one of best cleaning methods for the thermocouple tip.

  19. A Low Temperature Analysis of the Boundary Driven Kawasaki Process (United States)

    Maes, Christian; O'Kelly de Galway, Winny


    Low temperature analysis of nonequilibrium systems requires finding the states with the longest lifetime and that are most accessible from other states. We determine these dominant states for a one-dimensional diffusive lattice gas subject to exclusion and with nearest neighbor interaction. They do not correspond to lowest energy configurations even though the particle current tends to zero as the temperature reaches zero. That is because the dynamical activity that sets the effective time scale, also goes to zero with temperature. The result is a non-trivial asymptotic phase diagram, which crucially depends on the interaction coupling and the relative chemical potentials of the reservoirs.

  20. Analysis of optimal design of low temperature economizer (United States)

    Song, J. H.; Wang, S.


    This paper has studied the Off-design characteristic of low temperature economizer system based on thermodynamics analysis. Based on the data from one 1000 MW coal-fired unit, two modes of operation are contrasted and analyzed. One is to fix exhaust gas temperature and the other one is to take into account both of the average temperature difference and the exhaust gas temperature. Meanwhile, the cause of energy saving effect change is explored. Result shows that: in mode 1, the amount of decrease in coal consumption reduces from 1.11 g/kWh (under full load) to 0.54 g/kWh (under half load), and in mode 2, when the load decreases from 90% to 50%, the decrease in coal consumption reduces from 1.29 g/kWh to 0.84 g/kWh. From the result, under high load, the energy saving effect is superior, and under lower work load, energy saving effect declines rapidly when load is reduced. When load changes, the temperature difference of heat transfer, gas flow, the flue gas heat rejection and the waste heat recovery change. The energy saving effect corresponding changes result in that the energy saving effect under high load is superior and more stable. However, rational adjustment to the temperature of outlet gas can alleviate the decline of the energy saving effect under low load. The result provides theoretical analysis data for the optimal design and operation of low temperature economizer system of power plant.

  1. Prospective analysis of splinting the first carpometacarpal joint: an objective, subjective, and radiographic assessment. (United States)

    Weiss, S; LaStayo, P; Mills, A; Bramlet, D


    Predisposing factors contributing to the development of first carpometacarpal (CMC) osteoarthritis include an inherent laxity or incongruency of this joint, a shallow trapezium saddle, and heavy stresses placed on the joint with pinching and grasping. Splinting is a common mode of conservative treatment for CMC osteoarthritis. This study assessed the objective and subjective responses of patients with CMC osteoarthritis who wore short and long opponens splints, as well as radiographic changes associated with wearing of the splints. The study evaluated 26 hands. Each patient was assigned at random to wear the long or the short splint first. Patients wore the splints for one week. They then documented function in their splints (on 22 activities of daily living) and rated splint satisfaction and pain levels on visual analog scales. One week after application of the first splint, the second splint was applied and worn for one week, and all measures were repeated. On the final visit, tip pinches were evaluated and x-rays were taken to assess subluxation. One-way repeated-measure analysis and paired comparison were used to analyze the pinch, pain, radiographic, and splint-rating measures. Descriptive statistics were used to assess activity-of-daily-living function and splint preference. Both splints appear to reduce subluxation at the first CMC joint in patients with grades 1 and 2 osteoarthritis. The majority of the patients picked the short splint when asked at the end of the study which splint they preferred. The splints do not appear to increase pinch strength or affect pain levels associated with the performance of pinch strength measurements. This study supports anecdotal evidence that patients with CMC osteoarthritis get pain relief with splinting.

  2. Engineering studies on joint bar integrity, part II : finite element analysis (United States)


    This paper is the second in a two-part series describing : research sponsored by the Federal Railroad Administration : (FRA) to study the structural integrity of joint bars. In Part I, : observations from field surveys of joint bar inspections : cond...

  3. Thermographic analysis of body surface temperature of mammals. (United States)

    Mortola, Jacopo P


    Among mammals, the similarity in body temperature indicates that body size differences in heat loss must match the body size differences in heat production. This study tested the possibility that body surface temperature (Tbs), responsible for heat loss through radiation and convection, may vary systematically with the animal's body mass (M). Tbs was measured by whole body thermography in 53 specimens from 37 eutherian mammals ranging in M from a few grams to several tons. Numerous thermographs were taken from all angles, indoor, with the animals standing still in absence of air convection and of external radiant sources, at the ambient temperature of 20-22°C, 22-25°C, or 25-27°C. Data were analysed as whole body surface average, as average of the "effective" body surface area (those regions with temperatures exceeding ambient temperature by > 1.5°C or by > 5°C), as the peak histogram distribution and as average of the regions with the top 20% temperature values. For all modes of data analysis and at all ambient temperatures Tbs was independent of the animal's M. From these data, the heat loss by radiation and natural convection combined was estimated to vary to the 2/3 power of M. It is concluded that, for the same ambient conditions, the surface temperature responsible for radiation and convection is essentially body-size independent among mammals.



    Mr. Hariharan E *


    The composite structural members are highly used in the following applications such as aerospace, automobiles, marine, architecture etc., has attracted extensive attention in the past decades. A numerical and experimental study was carried out to identify the ultimate strength and failure modes of Bonded-single lap joints, Riveted-single lap joints and Hybrid-single lap joints at two different layers (3&4 Layer). In our project work, the effect of bonded, riveted, hybrid lap joints at differe...

  5. Stakeholder engagement analysis - a bioethics dilemma in patient-targeted intervention: patients with temporomandibular joint disorders. (United States)

    Barkhordarian, Andre; Demerjian, Gary; Jan, Allison; Sama, Nateli; Nguyen, Mia; Du, Angela; Chiappelli, Francesco


    Modern health care in the field of Medicine, Dentistry and Nursing is grounded in fundamental philosophy and epistemology of translational science. Recently in the U.S major national initiatives have been implemented in the hope of closing the gaps that sometimes exist between the two fundamental components of translational science, the translational research and translational effectiveness. Subsequent to these initiatives, many improvements have been made; however, important bioethical issues and limitations do still exist that need to be addressed. One such issue is the stakeholder engagement and its assessment and validation. Federal, state and local organizations such as PCORI and AHRQ concur that the key to a better understanding of the relationship between translational research and translational effectiveness is the assessment of the extent to which stakeholders are actively engaged in the translational process of healthcare. The stakeholder engagement analysis identifies who the stakeholders are, maps their contribution and involvement, evaluates their priorities and opinions, and accesses their current knowledge base. This analysis however requires conceptualization and validation from the bioethics standpoint. Here, we examine the bioethical dilemma of stakeholder engagement analysis in the context of the person-environment fit (PE-fit) theoretical model. This model is an approach to quantifying stakeholder engagement analysis for the design of patient-targeted interventions. In our previous studies of Alzheimer patients, we have developed, validated and used a simple instrument based on the PE-fit model that can be adapted and utilized in a much less studied pathology as a clinical model that has a wide range of symptoms and manifestations, the temporomandibular joint disorders (TMD). The temporomandibular joint (TMJ) is the jaw joint endowed with sensory and motor innervations that project from within the central nervous system and its dysfunction can

  6. Effects of clinical pathways in the joint replacement: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Faggiano F


    Full Text Available Abstract Background A meta-analysis was performed to evaluate the use of clinical pathways for hip and knee joint replacements when compared with standard medical care. The impact of clinical pathways was evaluated assessing the major outcomes of in-hospital hip and knee joint replacement processes: postoperative complications, number of patients discharged at home, length of in-hospital stay and direct costs. Methods Medline, Cinahl, Embase and the Cochrane Central Register of Controlled Trials were searched. The search was performed from 1975 to 2007. Each study was assessed independently by two reviewers. The assessment of methodological quality of the included studies was based on the Jadad methodological approach and on the New Castle Ottawa Scale. Data analysis abided by the guidelines set out by The Cochrane Collaboration regarding statistical methods. Meta-analyses were performed using RevMan software, version 4.2. Results Twenty-two studies met the study inclusion criteria and were included in the meta-analysis for a total sample of 6,316 patients. The aggregate overall results showed significantly fewer patients suffering postoperative complications in the clinical pathways group when compared with the standard care group. A shorter length of stay in the clinical pathway group was also observed and lower costs during hospital stay were associated with the use of the clinical pathways. No significant differences were found in the rates of discharge to home. Conclusion The results of this meta-analysis show that clinical pathways can significantly improve the quality of care even if it is not possible to conclude that the implementation of clinical pathways is a cost-effective process, because none of the included studies analysed the cost of the development and implementation of the pathways. Based on the results we assume that pathways have impact on the organisation of care if the care process is structured in a standardised way

  7. [Comparative analysis of blood loss and haemodynamic changes in endoprosthesis replacing of coxofemoral joint in patients with bilateral coxarthrosis]. (United States)

    Maksimov, B I; Nikolenko, V K


    Comparative analysis of blood loss and haemodynamic changes in endoprosthesis replacing of coxofemoral joint in patients with bilateral coxarthrosis. Endoprosthesis replacement of coxofemoral joint is the method of choice in treatment of bilateral coxarthrosis which can eliminate the pain syndrome and physical restraint of patients. Also this method gives the opportunity for fast return to the labor activity. However, this orthopedic device is related to the different complications, the most dangerous among them is the blood loss. The method of the single-stage bilateral endoprosthesis replacement of coxofemoral joint was developed and introduced in the center of traumatology and orthopedics of the Central Military Clinical Hospital n.a N.N.Burdenko. The offered method let to reduce the total intraoperative blood loss at average to 30% in comparison with the consequential surrogation of two coxofemoral joint.

  8. [Analysis of influential factors for job burnout among managers in a joint venture in Guangzhou, China]. (United States)

    Lin, Qiu-hong; Jiang, Chao-qiang; Liu, Yi-min; Guo, Jing-yi; Lam, Tai Hing


    To investigate the influential factors for job burnout among the managerial staff in a Sino-Japanese joint venture automobile manufacturer in Guangzhou, China. A total of 288 managers in a Sino-Japanese joint venture automobile manufacturer were surveyed using the Occupational Stress Indicator, Maslach Burnout Inventory (MBI), Eysenck Personality Questionnaire, Simplified Coping Style Questionnaire, and Social Support Rating Scale. On the depersonalization dimension, the male managers had significantly higher scores than the female managers. The scores of emotion exhaustion and depersonalization of MBI showed significant differences among the managers with different levels of occupational stress. The path analysis showed that occupational stress, neuroticism, and psychoticism had negative effects on emotion exhaustion, while job satisfaction and utilization of social support had direct positive effects on emotion exhaustion. Occupational stress, psychoticism, and passive coping style had direct negative effects on depersonalization, while job satisfaction, objective support, and utilization of social support had positive effects on depersonalization. Job satisfaction and active coping style had positive effects on sense of personal accomplishment, while passive coping style had a negative effect on sense of personal accomplishment. Personality exerted its effect on social support through coping style and thus on job satisfaction and job burnout. Male managers have a greater propensity to depersonalization than their female counterparts. High occupational stress is a risk factor for job burnout. Personality, social support, and coping style are influential factors for job burnout.

  9. Analysis of debonding in single lap joints based on employment of ultrasounds (United States)

    Scarselli, G.; Nicassio, F.


    In this study the amplitude and the phase of the structural response of samples of Single Lap Joint (SLJ) subjected to ultrasonic harmonic excitation was evaluated to identify and characterize the defects within the bonded region. Different parameters such as frequency, shape, and amplitude of the response signal coming back from the adhesive joint are key criteria for understanding the quality of the adhesion. Different metallic samples with the same geometry were experimentally tested: the defects were artificially introduced bonding partially two plates and changing the extension of the debonded region: two piezoelectric sensors (one exciting, one receiver) were attached on each of the two bonded plates. In this way, different experimental tests were carried out in order to study the influence of debonded regions on SLJ structural behavior. The structural dynamic response of the debonded samples was investigated and compared with the predictions of numerical models, for each SLJ, introducing viscoelastic properties for the adhesive layer, and applying the harmonic excitation. Moreover the numerical modal analysis was used to understand the experimental results by a proper description of viscoelastic tape behavior. The numerical simulations were used to find correlation between the content of the acquired signals and the defects of adhesion.

  10. Pharmacokinetic Analysis of an Oral Multicomponent Joint Dietary Supplement (Phycox®) in Dogs. (United States)

    Martinez, Stephanie E; Lillico, Ryan; Lakowski, Ted M; Martinez, Steven A; Davies, Neal M


    Despite the lack of safety, efficacy and pharmacokinetic (PK) studies, multicomponent dietary supplements (nutraceuticals) have become increasingly popular as primary or adjunct therapies for clinical osteoarthritis in veterinary medicine. Phycox ® is a line of multicomponent joint support supplements marketed for joint health in dogs and horses. Many of the active constituents are recognized anti-inflammatory and antioxidant agents. Due to a lack of PK studies in the literature for the product, a pilot PK study of select constituents in Phycox ® was performed in healthy dogs. Two novel methods of analysis were developed and validated for quantification of glucosamine and select polyphenols using liquid chromatography-tandem mass spectrometry. After a single oral (PO) administrated dose of Phycox ® , a series of blood samples from dogs were collected for 24 h post-dose and analyzed for concentrations of glucosamine HCl, hesperetin, resveratrol and naringenin. Non-compartmental PK analyses were carried out. Glucosamine was detected up to 8 h post-dose with a T max of 2 h and C max of 9.69 μg/mL. The polyphenols were not found at detectable concentrations in serum samples. Co-administration of glucosamine in the Phycox ® formulation may enhance the absorption of glucosamine as determined by comparison of glucosamine PK data in the literature.

  11. Butt Joint Tool Commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, N N


    ITER Central Solenoid uses butt joints for connecting the pancakes in the CS module. The principles of the butt joining of the CICC were developed by the JAPT during CSMC project. The difference between the CSMC butt joint and the CS butt joint is that the CS butt joint is an in-line joint, while the CSMC is a double joint through a hairpin jumper. The CS butt joint has to carry the hoop load. The straight length of the joint is only 320 mm, and the vacuum chamber around the joint has to have a split in the clamp shell. These requirements are challenging. Fig.1 presents a CSMC joint, and Fig.2 shows a CS butt joint. The butt joint procedure was verified and demonstrated. The tool is capable of achieving all specified parameters. The vacuum in the end was a little higher than the target, which is not critical and readily correctable. We consider, tentatively that the procedure is established. Unexpectedly, we discover significant temperature nonuniformity in the joint cross section, which is not formally a violation of the specs, but is a point of concern. All testing parameters are recorded for QA purposes. We plan to modify the butt joining tool to improve its convenience of operation and provide all features necessary for production of butt joints by qualified personnel.

  12. Application of FE-analysis in Design and Verification of Bolted Joints according to VDI 2230 at CERN

    CERN Document Server

    Apeland, Jorgen; Dassa, Luca; Welo, Torgeir

    This thesis investigates how finite element analysis (FEA) can be used to simplify and improve analysis of bolted joints according to the guideline VDI 2230. Some aspects of how FEA can be applied to aid design and verification of bolted joints are given in the guideline, but not in a streamlined way that makes it simple and efficient to apply. The scope of this thesis is to clarify how FEA and VDI 2230 can be combined in analysis of bolted joints, and to present a streamlined workflow. The goal is to lower the threshold for carrying out such combined analysis. The resulting benefits are improved analysis validity and quality, and improved analysis efficiency. A case from the engineering department at CERN, where FEA has been used in analysis of bolted joints is used as basis to identify challenges in combining FEA and VDI 2230. This illustrates the need for a streamlined analysis strategy and well described workflow. The case in question is the Helium vessel (pressure vessel) for the DQW Crab Cavities, whi...

  13. jNMFMA: a joint non-negative matrix factorization meta-analysis of transcriptomics data. (United States)

    Wang, Hong-Qiang; Zheng, Chun-Hou; Zhao, Xing-Ming


    Tremendous amount of omics data being accumulated poses a pressing challenge of meta-analyzing the heterogeneous data for mining new biological knowledge. Most existing methods deal with each gene independently, thus often resulting in high false positive rates in detecting differentially expressed genes (DEG). To our knowledge, no or little effort has been devoted to methods that consider dependence structures underlying transcriptomics data for DEG identification in meta-analysis context. This article proposes a new meta-analysis method for identification of DEGs based on joint non-negative matrix factorization (jNMFMA). We mathematically extend non-negative matrix factorization (NMF) to a joint version (jNMF), which is used to simultaneously decompose multiple transcriptomics data matrices into one common submatrix plus multiple individual submatrices. By the jNMF, the dependence structures underlying transcriptomics data can be interrogated and utilized, while the high-dimensional transcriptomics data are mapped into a low-dimensional space spanned by metagenes that represent hidden biological signals. jNMFMA finally identifies DEGs as genes that are associated with differentially expressed metagenes. The ability of extracting dependence structures makes jNMFMA more efficient and robust to identify DEGs in meta-analysis context. Furthermore, jNMFMA is also flexible to identify DEGs that are consistent among various types of omics data, e.g. gene expression and DNA methylation. Experimental results on both simulation data and real-world cancer data demonstrate the effectiveness of jNMFMA and its superior performance over other popular approaches. R code for jNMFMA is available for non-commercial use via Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail:

  14. Genetic divergence through joint analysis of morphoagronomic and molecular characters in accessions of Jatropha curcas. (United States)

    Pestana-Caldas, C N; Silva, S A; Machado, E L; de Souza, D R; Cerqueira-Pereira, E C; Silva, M S


    The aim of this study was to investigate the genetic divergence between accessions of Jatropha curcas through joint analysis of morphoagronomic and molecular characters. To this end, we investigated 11 morphoagronomic characters and performed molecular genotyping, using 23 inter-simple sequence repeat (ISSR) primers in 46 accessions of J. curcas. We calculated the contribution of each character on divergence using analysis of variance. The grouping among accessions was performed using the Ward-MLM (modified location model) method, using morphoagronomic and molecular data, whereas the cophenetic correlation was obtained based on Gower's algorithm. There were significant differences in all growth-related characteristics: number of primary and secondary branches per plant, plant height, and stem diameter. For characters related to grain production, differences were found for number of fruit clusters per plant and number of inflorescence clusters per plant and average number of seeds per fruit. The greatest phenotypic variation was found in plant height (59.67- 222.33 cm), whereas the smallest variation was found in average number of seeds per fruit (0-2.90), followed by the number of fruit clusters per plant (0-8.67). In total, 94 polymorphic ISSR fragments were obtained. The genotypic grouping identified six groups, indicating that there is genetic divergence among the accessions. The most promising crossings for future hybridization were identified among accessions UFRB60 and UFVJC45, and UFRB61 and UFVJC18. In conclusion, the joint analysis of morphoagronomic characters and ISSR markers is an efficient method to assess the genetic divergence in J. curcas.

  15. Analysis on Sealing Reliability of Bolted Joint Ball Head Component of Satellite Propulsion System (United States)

    Guo, Tao; Fan, Yougao; Gao, Feng; Gu, Shixin; Wang, Wei


    Propulsion system is one of the important subsystems of satellite, and its performance directly affects the service life, attitude control and reliability of the satellite. The Paper analyzes the sealing principle of bolted joint ball head component of satellite propulsion system and discuss from the compatibility of hydrazine anhydrous and bolted joint ball head component, influence of ground environment on the sealing performance of bolted joint ball heads, and material failure caused by environment, showing that the sealing reliability of bolted joint ball head component is good and the influence of above three aspects on sealing of bolted joint ball head component can be ignored.

  16. Women with more severe degrees of temporomandibular disorder exhibit an increase in temperature over the temporomandibular joint

    Directory of Open Access Journals (Sweden)

    Almir Vieira Dibai-Filho


    Conclusion: FAI score was associated with skin temperature over the TMJ, as determined by infrared thermography, in this sample. Women with more severe TMD demonstrated a bilateral increase in skin temperature.

  17. Cross-Population Joint Analysis of eQTLs: Fine Mapping and Functional Annotation (United States)

    Wen, Xiaoquan; Luca, Francesca; Pique-Regi, Roger


    Mapping expression quantitative trait loci (eQTLs) has been shown as a powerful tool to uncover the genetic underpinnings of many complex traits at molecular level. In this paper, we present an integrative analysis approach that leverages eQTL data collected from multiple population groups. In particular, our approach effectively identifies multiple independent cis-eQTL signals that are consistent across populations, accounting for population heterogeneity in allele frequencies and linkage disequilibrium patterns. Furthermore, by integrating genomic annotations, our analysis framework enables high-resolution functional analysis of eQTLs. We applied our statistical approach to analyze the GEUVADIS data consisting of samples from five population groups. From this analysis, we concluded that i) jointly analysis across population groups greatly improves the power of eQTL discovery and the resolution of fine mapping of causal eQTL ii) many genes harbor multiple independent eQTLs in their cis regions iii) genetic variants that disrupt transcription factor binding are significantly enriched in eQTLs (p-value = 4.93 × 10-22). PMID:25906321

  18. Facilitating joint chaos and fractal analysis of biosignals through nonlinear adaptive filtering.

    Directory of Open Access Journals (Sweden)

    Jianbo Gao

    Full Text Available BACKGROUND: Chaos and random fractal theories are among the most important for fully characterizing nonlinear dynamics of complicated multiscale biosignals. Chaos analysis requires that signals be relatively noise-free and stationary, while fractal analysis demands signals to be non-rhythmic and scale-free. METHODOLOGY/PRINCIPAL FINDINGS: To facilitate joint chaos and fractal analysis of biosignals, we present an adaptive algorithm, which: (1 can readily remove nonstationarities from the signal, (2 can more effectively reduce noise in the signals than linear filters, wavelet denoising, and chaos-based noise reduction techniques; (3 can readily decompose a multiscale biosignal into a series of intrinsically bandlimited functions; and (4 offers a new formulation of fractal and multifractal analysis that is better than existing methods when a biosignal contains a strong oscillatory component. CONCLUSIONS: The presented approach is a valuable, versatile tool for the analysis of various types of biological signals. Its effectiveness is demonstrated by offering new important insights into brainwave dynamics and the very high accuracy in automatically detecting epileptic seizures from EEG signals.

  19. A stochastic model for the analysis of maximum daily temperature (United States)

    Sirangelo, B.; Caloiero, T.; Coscarelli, R.; Ferrari, E.


    In this paper, a stochastic model for the analysis of the daily maximum temperature is proposed. First, a deseasonalization procedure based on the truncated Fourier expansion is adopted. Then, the Johnson transformation functions were applied for the data normalization. Finally, the fractionally autoregressive integrated moving average model was used to reproduce both short- and long-memory behavior of the temperature series. The model was applied to the data of the Cosenza gauge (Calabria region) and verified on other four gauges of southern Italy. Through a Monte Carlo simulation procedure based on the proposed model, 105 years of daily maximum temperature have been generated. Among the possible applications of the model, the occurrence probabilities of the annual maximum values have been evaluated. Moreover, the procedure was applied for the estimation of the return periods of long sequences of days with maximum temperature above prefixed thresholds.

  20. An Assessment of the Mechanical Properties and Microstructural Analysis of Dissimilar Material Welded Joint between Alloy 617 and 12Cr Steel

    Directory of Open Access Journals (Sweden)

    Hafiz Waqar Ahmad


    Full Text Available The most effective method to reduce CO2 gas emission from the steam power plant is to improve its performance by elevating the steam temperature to more than 700 °C. For this, it is necessary to develop applicable materials at high temperatures. Ni-based Alloy 617 and 12Cr steel are used in steam power plants, due to their remarkable mechanical properties, high corrosion resistance, and creep strength. However, since Alloy 617 and 12Cr steel have different chemical compositions and thermal and mechanical properties, it is necessary to develop dissimilar material welding technologies. Moreover, in order to guarantee the reliability of dissimilar material welded structures, the assessment of mechanical and metallurgical properties, fatigue strength, fracture mechanical analysis, and welding residual stress analysis should be conducted on dissimilar material welded joints. In this study, first, multi-pass dissimilar material welding between Alloy 617 and 12Cr steel was performed under optimum welding conditions. Next, mechanical properties were assessed, including the static tensile strength, hardness distribution, and microstructural analysis of a dissimilar material welded joint. The results indicated that the yield strength and tensile strength of the dissimilar metal welded joint were higher than those of the Alloy 617 base metal, and lower than those of the 12Cr steel base metal. The hardness distribution of the 12Cr steel side was higher than that of Alloy 617 and the dissimilar material weld metal zone. It was observed that the microstructure of Alloy 617 HAZ was irregular austenite grain, while that of 12Cr steel HAZ was collapsed martensite grain, due to repeatable heat input during multi-pass welding.

  1. Joint Intelligence Analysis Complex: DOD Partially Used Best Practices for Analyzing Alternatives and Should Do So Fully for Future Military Construction Decisions (United States)


    JOINT INTELLIGENCE ANALYSIS COMPLEX DOD Partially Used Best Practices for Analyzing Alternatives and Should Do So Fully for Future...GAO Found The Department of Defense’s (DOD) decision to consolidate and relocate its Joint Intelligence Analysis Complex (JIAC) to Royal Air Force...processes. GAO continues to believe that its recommendation is valid, as discussed in this report. Page i GAO-16-853 Joint Intelligence Analysis Complex

  2. Hemispherical Resonator Gyroscope Accuracy Analysis Under Temperature Influence

    Directory of Open Access Journals (Sweden)

    Boran LI


    Full Text Available Frequency splitting of hemispherical resonator gyroscope will change as system operating temperature changes. This phenomenon leads to navigation accuracy of hemispherical resonator gyroscope reduces. By researching on hemispherical resonator gyroscope dynamical model and its frequency characteristic, the frequency splitting formula and the precession angle formula of gyroscope vibrating mode based on hemispherical resonator gyroscope dynamic equation parameters are derived. By comparison, gyroscope precession angle deviation caused by frequency splitting can be obtained. Based on analysis of temperature variation against gyroscope resonator, the design of hemispherical resonator gyroscope feedback controller under temperature variation conditions is researched and the maximum theoretical fluctuation of gyroscope dynamical is determined by using a numerical analysis example.

  3. Thermal analysis of high temperature phase transformations of steel

    Directory of Open Access Journals (Sweden)

    K. Gryc


    Full Text Available The series of thermal analysis measurements of high temperature phase transformations of real grain oriented electrical steel grade under conditions of two analytical devices (Netzsch STA 449 F3 Jupiter; Setaram SETSYS 18TM were carried out. Two thermo analytical methods were used (DTA and Direct thermal analysis. The different weight of samples was used (200 mg, 23 g. The stability/reproducibility of results obtained by used methodologies was verified. The liquidus and solidus temperatures for close to equilibrium conditions and during cooling (20 °C/min; 80 °C/min were determined. It has been shown that the higher cooling rate lead to lower temperatures for start and end of solidification process of studied steel grade.

  4. Mutational analysis a joint framework for Cauchy problems in and beyond vector spaces

    CERN Document Server

    Lorenz, Thomas


    Ordinary differential equations play a central role in science and have been extended to evolution equations in Banach spaces. For many applications, however, it is difficult to specify a suitable normed vector space. Shapes without a priori restrictions, for example, do not have an obvious linear structure. This book generalizes ordinary differential equations beyond the borders of vector spaces with a focus on the well-posed Cauchy problem in finite time intervals. Here are some of the examples: - Feedback evolutions of compact subsets of the Euclidean space - Birth-and-growth processes of random sets (not necessarily convex) - Semilinear evolution equations - Nonlocal parabolic differential equations - Nonlinear transport equations for Radon measures - A structured population model - Stochastic differential equations with nonlocal sample dependence and how they can be coupled in systems immediately - due to the joint framework of Mutational Analysis. Finally, the book offers new tools for modelling.

  5. Joint analysis of panel count data with an informative observation process and a dependent terminal event. (United States)

    Zhou, Jie; Zhang, Haixiang; Sun, Liuquan; Sun, Jianguo


    Panel count data occur in many clinical and observational studies, and in many situations, the observation process may be informative and also there may exist a terminal event such as death which stops the follow-up. In this article, we propose a new joint model for the analysis of panel count data in the presence of both an informative observation process and a dependent terminal event via two latent variables. For the inference on the proposed models, a class of estimating equations is developed and the resulting estimators are shown to be consistent and asymptotically normal. In addition, a lack-of-fit test is provided for assessing the adequacy of the models. Simulation studies suggest that the proposed approach works well for practical situations. A real example from a bladder cancer clinical trial is used to illustrate the proposed methods.

  6. Joint impacts of immigration on wages and employment: review and meta-analysis (United States)

    Longhi, S.; Nijkamp, P.; Poot, J.


    A burgeoning literature has emerged during the last two decades to assess the economic impacts of immigration on host countries. In this paper, we outline the quantitative approaches presented in the literature to estimate the impact of immigration on the labour market, particularly at the regional level. We then revisit the joint impacts of immigration on wages and employment using a meta-analytic approach. As a novel contribution to previous meta-analyses on labour market impacts, we use a simultaneous equations approach to the meta-analysis of wage and employment effects. Using 129 effect sizes, we find that the observed local wage and employment effects are very small indeed. Generally, the employment impact is more pronounced in Europe than in the United States. Controls for endogeneity show a somewhat more negative impact. Wage rigidity increases the magnitude of the employment impact on the native born. The demarcation of the local labour market in terms of geography and skills matters also.

  7. jMOSAiCS: joint analysis of multiple ChIP-seq datasets (United States)


    The ChIP-seq technique enables genome-wide mapping of in vivo protein-DNA interactions and chromatin states. Current analytical approaches for ChIP-seq analysis are largely geared towards single-sample investigations, and have limited applicability in comparative settings that aim to identify combinatorial patterns of enrichment across multiple datasets. We describe a novel probabilistic method, jMOSAiCS, for jointly analyzing multiple ChIP-seq datasets. We demonstrate its usefulness with a wide range of data-driven computational experiments and with a case study of histone modifications on GATA1-occupied segments during erythroid differentiation. jMOSAiCS is open source software and can be downloaded from Bioconductor [1]. PMID:23844871

  8. Application Of Fourier Series Analysis To Temperature Data ...

    African Journals Online (AJOL)

    This Paper seeks to model a periodic time series using Fourier Series Analysis Method and to use such model to forcast future values of such data. The mean monthly temperature of Uyo Metropolis consisting of 180 data points (1991 – 2006) are collected for the study. The parameter estimates of the Fourier series model ...

  9. Simulation of temperature distribution by finite element analysis on ...

    Indian Academy of Sciences (India)

    Several optical and mechanical components of the beamline are exposed to high intensity synchrotron radiation while in operation. The temperature rise on different components of the beamline on exposure to the synchrotron beam has been simulated by finite element analysis. Design of the cooling mechanism for each of ...

  10. Analysis of soil temperature harmonics and filtering characteristics ...

    African Journals Online (AJOL)

    The incident solar energy determines the periodic variation of the soil temperatures and the attenuation with depth. Harmonic analysis of soil ... The results show that the soil behaves like an energy filter and an electrical analogue was modeled to simulate the filtering characteristics of the soil. It was found that the soil acts as ...

  11. Use of objective analysis to estimate winter temperature and ...

    Indian Academy of Sciences (India)

    Norway, Greenland and Antarctica as a part of a wide variety of terrestrial modeling studies (e.g.,. Liston and Sturm 1998, 2002; Bruland et al 2004;. Liston and Winther 2005). Present study estimates temperature and precipitation intensity on various regions of Indian. Himalaya by using Barnes (1973) objective analysis.

  12. Quantitative analysis of morphological change in the articular disc of temporomandibular joint on MR image

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, Chinami; Kobayashi, Kaoru; Imanaka, Masahiro; Yuasa, Masao; Yamamoto, Akira [Tsurumi Univ., Yokohama (Japan). School of Dental Medicine; Otonari, Takamichi


    This study investigated morphological changes of the articular disc by measurement of the volume of disc on MR images. This retrospective study investigated 16 joints; 8 showed an unchanged disc configuration and 8 showed a changed configuration during the follow-up period. MR imaging was performed with a 0.3 Tesla MR imager (HITACHI MEDICAL, Tokyo, Japan) using a surface coil measuring 9 cm in diameter. The images were obtained on a corrected sagittal plane in a closed mouth position. Volume measurements of the articular disc were as follows: Two regions of interest were placed over the articular disc. Measurements of the signal intensity were made directly on the MR imager. Maximal and minimal values of signal intensity were calculated from the mean value {+-}2SD. The maximal value of signal intensity was determined to be higher than the mean value +2SD. Minimal value of signal intensity was determined to be below the value -2SD. The area of the disc was measured directly using level detection software by inputting maximal and minimal signal intensities. Volume was calculated using the area identified on each slice multiplied by 4 mm (slice thickness). Wilcoxon matched-pairs signed-rank test was used for statistical analysis. Unchanged group showed similar disc volumes on both the initial MR image and follow up MR image. However, the changed group showed some difference in volume between initial MR image and follow-up MR image. This measurement technique has been shown to be a useful technique for quantitative analysis of morphological changes in the articular disc in the temporomandibular joint on MR image. (author)

  13. Analysis Technique on Water Permeability in Concrete with Cold Joint considering Micro Pore Structure and Mineral Admixture

    Directory of Open Access Journals (Sweden)

    Se-Jin Choi


    Full Text Available Cold joint in concrete due to delayed concrete placing may cause a reduced shear resistance and increased water permeation. This study presents an analytical model based on the concept of REV (Representative Element Volume to assess the effect of water permeability in cold joint concrete. Here, OPC (Ordinary Portland Cement concrete samples with cold joint are prepared and WPT (Water Permeability Test is performed on the samples cured for 91 days. In order to account for the effect of GGBFS (Granulated Ground Blast Furnace Slag on water permeability, concrete samples with the same W/B (Water to Binder ratio and 40% replacement ratio of GGBFS are tested as well. Utilizing the previous models handling porosity and saturation, the analysis technique for equivalent water permeability with effective cold joint width is proposed. Water permeability in cold joint increases to 140.7% in control case but it decreases to 120.7% through GGBFS replacement. Simulation results agree reasonably well with experimental data gathered for sound and cold joint concrete.

  14. Innovative Instrumentation and Analysis of the Temperature Measurement for High Temperature Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee


    The project entitled, ''Innovative Instrumentation and Analysis of the Temperature Measurement for High Temperature Gasification'', was successfully completed by the Principal Investigator, Dr. S. Lee and his research team in the Center for Advanced Energy Systems and Environmental Control Technologies at Morgan State University. The major results and outcomes were presented in semi-annual progress reports and annual project review meetings/presentations. Specifically, the literature survey including the gasifier temperature measurement, the ultrasonic application in cleaning application, and spray coating process and the gasifier simulator (cold model) testing has been successfully conducted during the first year. The results show that four factors (blower voltage, ultrasonic application, injection time intervals, particle weight) were considered as significant factors that affect the temperature measurement. Then the gasifier simulator (hot model) design and the fabrication as well as the systematic tests on hot model were completed to test the significant factors on temperature measurement in the second year. The advanced Industrial analytic methods such as statistics-based experimental design, analysis of variance (ANOVA) and regression methods were applied in the hot model tests. The results show that operational parameters (i.e. air flow rate, water flow rate, fine dust particle amount, ammonia addition) presented significant impact on the temperature measurement inside the gasifier simulator. The experimental design and ANOVA are very efficient way to design and analyze the experiments. The results show that the air flow rate and fine dust particle amount are statistically significant to the temperature measurement. The regression model provided the functional relation between the temperature and these factors with substantial accuracy. In the last year of the project period, the ultrasonic and subsonic cleaning methods and coating


    Energy Technology Data Exchange (ETDEWEB)

    Seong W. Lee


    The systematic tests of the gasifier simulator on the clean thermocouple were completed in this reporting period. Within the systematic tests on the clean thermocouple, five (5) factors were considered as the experimental parameters including air flow rate, water flow rate, fine dust particle amount, ammonia addition and high/low frequency device (electric motor). The fractional factorial design method was used in the experiment design with sixteen (16) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the un-balanced motor vibration frequency did not have the significant impact on the temperature changes in the gasifier simulator. For the fine dust particles testing, the amount of fine dust particles has significant impact to the temperature measurements in the gasifier simulator. The effects of the air and water on the temperature measurements show the same results as reported in the previous report. The ammonia concentration was included as an experimental parameter for the reducing environment in this reporting period. The ammonia concentration does not seem to be a significant factor on the temperature changes. The linear regression analysis was applied to the temperature reading with five (5) factors. The accuracy of the linear regression is relatively low, which is less than 10% accuracy. Nonlinear regression was also conducted to the temperature reading with the same factors. Since the experiments were designed in two (2) levels, the nonlinear regression is not very effective with the dataset (16 readings). An extra central point test was conducted. With the data of the center point testing, the accuracy of the nonlinear regression is much better than the linear regression.

  16. Brief communication: Cineradiographic analysis of the chimpanzee (Pan troglodytes) talonavicular and calcaneocuboid joints. (United States)

    Thompson, Nathan E; Holowka, Nicholas B; O'Neill, Matthew C; Larson, Susan G


    During terrestrial locomotion, chimpanzees exhibit dorsiflexion of the midfoot between midstance and toe-off of stance phase, a phenomenon that has been called the "midtarsal break." This motion is generally absent during human bipedalism, and in chimpanzees is associated with more mobile foot joints than in humans. However, the contribution of individual foot joints to overall foot mobility in chimpanzees is poorly understood, particularly on the medial side of the foot. The talonavicular (TN) and calcaneocuboid (CC) joints have both been suggested to contribute significantly to midfoot mobility and to the midtarsal break in chimpanzees. To evaluate the relative magnitude of motion that can occur at these joints, we tracked skeletal motion of the hindfoot and midfoot during passive plantarflexion and dorsiflexion manipulations using cineradiography. The sagittal plane range of motion was 38 ± 10° at the TN joint and 14 ± 8° at the CC joint. This finding indicates that the TN joint is more mobile than the CC joint during ankle plantarflexion-dorsiflexion. We suggest that the larger range of motion at the TN joint during dorsiflexion is associated with a rotation (inversion-eversion) across the transverse tarsal joint, which may occur in addition to sagittal plane motion. © 2014 Wiley Periodicals, Inc.

  17. Periarticular osteophytes as an appendicular joint stress marker (JSM: analysis in a contemporary Japanese skeletal collection.

    Directory of Open Access Journals (Sweden)

    Toshiyuki Tsurumoto

    Full Text Available OBJECTIVE: The aim of this study was to investigate the possibility that periarticular osteophytes plays a role as a appendicular joint stress marker (JSM which reflects the biomechanical stresses on individuals and populations. METHODS: A total of 366 contemporary Japanese skeletons (231 males, 135 females were examined closely to evaluate the periarticular osteophytes of six major joints, the shoulder, elbow, wrist, hip, knee, and ankle and osteophyte scores (OS were determined using an original grading system. These scores were aggregated and analyzed statistically from some viewpoints. RESULTS: All of the OS for the respective joints were correlated logarithmically with the age-at-death of the individuals. For 70 individuals, in whom both sides of all six joints were evaluated without missing values, the age-standardized OS were calculated. A right side dominancy was recognized in the joints of the upper extremities, shoulder and wrist joints, and the bilateral correlations were large in the three joints on the lower extremity. For the shoulder joint and the hip joint, it was inferred by some distinctions that systemic factors were relatively large. All of these six joints could be assorted by the extent of systemic and local factors on osteophytes formation. Moreover, when the age-standardized OS of all the joints was summed up, some individuals had significantly high total scores, and others had significantly low total scores; namely, all of the individuals varied greatly in their systemic predisposition for osteophytes formation. CONCLUSIONS: This study demonstrated the significance of periarticular osteophytes; the evaluating system for OS could be used to detect differences among joints and individuals. Periarticular osteophytes could be applied as an appendicular joint stress marker (JSM; by applying OS evaluating system for skeletal populations, intra-skeletal and inter-skeletal variations in biomechanical stresses throughout the

  18. In vivo analysis of trapeziometacarpal joint arthrokinematics during multi-directional thumb motions. (United States)

    Su, Fong-Chin; Lin, Chien-Ju; Wang, Chien-Kuo; Chen, Guan-Po; Sun, Yung-Nien; Chuang, Alan K; Kuo, Li-Chieh


    The investigation of the joint arthrokinematics of the trapeziometacarpal joint is critical to comprehend the causative mechanism underlying this common form of osteoarthritis. Therefore, the purpose of this study is to evaluate the arthrokinematics of the trapeziometacarpal joint during thumb postures in vivo. Fifteen healthy participants were enrolled in this study. Static computed tomography images of the 1st metacarpal bone and trapezium were taken at specific thumb postures during thumb flexion-extension, abduction-adduction, and circumduction motions. Images were analyzed to examine the joint gliding, expressed as displacement of the centroid of the articular surface of the 1st metacarpal bone, relative to the trapezium. The gliding ratio, defined as joint gliding in each direction normalized to the dimension of the trapezium joint surface in the given direction, was computed and compared between different thumb motions. The results indicate that thumb motions influenced joint gliding. The centroids of the articular surface of the 1st metacarpal bone were primarily located at the central and dorsal-radial regions while executing these motions. The maximum joint gliding of the 1st metacarpal bone occurred in the radial-ulnar direction when performing abduction-adduction, and in the dorsal-volar direction while performing flexion-extension and circumduction, with the gliding ratio values of 42.35%, 51.65%, and 51.85%, respectively. Activities that involved abduction-adduction in the trapeziometacarpal joint caused greater joint gliding in the ulnar-radial direction, while flexion-extension resulted in greater joint gliding in the dorsal-volar and distal-proximal directions. Understanding normal joint kinematics in vivo may provide insights into the possible mechanism leading to osteoarthritis of the trapeziometacarpal joint, and help to improve the design of implants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Research and development for the high-temperature helium-leak detection system (Joint research). Part 2. Development of temperature sensors using optical fibre for the HTTR

    Energy Technology Data Exchange (ETDEWEB)

    Sakaba, Nariaki; Nakazawa, Toshio; Kawasaki, Kozo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Urakami, Masao; Saisyu, Sadanori [Japan Atomic Power Co., Tokyo (Japan)


    In the second stage of the research and development for a high-temperature helium-leak detection system, the temperature sensor using optical fibres was studied. The sensor detects the helium leakage by the temperature increase surrounded optical fibre with or without heat insulator. Moreover, the applicability of high temperature equipments as the HTTR system was studied. With the sensor we detected 5.0-20.0 cm{sup 3}/s helium leakages within 60 minutes. Also it was possible to detect earlier when the leakage level is at 20.0 cm {sup 3}/s. (author)


    Directory of Open Access Journals (Sweden)

    Teerawong Laosuwan


    Full Text Available This research aimed to present the technique for land surface temperature analysis with the data from Landsat-8 Operational Land Imager (OLI /Thermal Infrared Sensors (TIR in Meuang Maha Sarakham District, Maha Sarakham Province, Northeastern, Thailand. The research was conducted as following three steps: 1 Collecting the satellite data in thermal infrared band from Landsat-8 TIR satellite to adjust the value of Top of Atmosphere (ToA Reflectance and then analyzing the land surface temperature 2 Collecting multi-band data from Landsat-8 OLI satellite to adjust the value of Top of Atmosphere (ToA Reflectance and then analyzing values of Normalized Difference Vegetation Index (NDVI, Fractional Vegetation Cover (FVC and Land surface Emissivity (LSE 3 Bringing the results of 1 and 2 to analyze the land surface temperature with split window algorithm. The research results indicated that the analysis of the data from Landsat-8 OLI/TIR satellites in 18 March 2015 indicated a mean temperature of 33.57 °C.

  1. Hotspot temperature calculation and quench analysis on ITER busbar

    Energy Technology Data Exchange (ETDEWEB)

    Rong, J., E-mail: [University of Science and Technology of China, Hefei 230027 (China); Huang, X.Y.; Song, Y.T.; Wu, S.T. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)


    Highlights: • The hotspot temperature is calculated in the case of different extra copper in this paper. • The MQE (minimum quench energy) is carried out as the external heating to trigger a quench in busbar. • The temperature changes after quench is analyzed by Gandalf code in the case of different extra copper and no helium. • The normal length is carried out in the case of different extra copper by Gandalf code. - Abstract: This paper describes the analysis of ITER feeder busbar, the hotspot temperature of busbar is calculated by classical method in the case of 0%, 50%, 75% and 100% extra copper (copper strands). The quench behavior of busbar is simulated by 1-D Gandalf code, and the MQE (minimum quench energy) is estimated in classical method as initial external heat in Gandalf input file. The temperature and the normal length of conductor are analyzed in the case of 0%, 50% and 100% extra copper and no helium. By hotspot temperature, conductor temperature and normal length are contrasted in different extra copper cases, it is shown that the extra copper play an important role in quench protecting.

  2. A computer-aided tracking and motion analysis with ultrasound (CAT & MAUS) system for the description of hip joint kinematics. (United States)

    Jia, Rui; Mellon, Stephen; Monk, Paul; Murray, David; Noble, J Alison


    Investigation of joint kinematics contributes to developing a better understanding of musculoskeletal conditions. However, the most commonly used optoelectronic motion analysis systems cannot determine the movements of underlying bone landmarks with high accuracy because of soft tissue artefacts. The aim of this paper was to present a computer-aided measurement system to track the underlying bone anatomy in a 3D global coordinate frame and describe hip joint kinematics of ten healthy volunteers during gait. We have developed a measurement tool with an image-based computer-aided post-processing pipeline for automatic bone segmentation in ultrasound (US) images and a globally optimal 3D surface-to-surface registration method to quantify hip joint movements. The segmentation algorithm exploits US intensity profiles, including information about the integrated backscattering, acoustic shadows, and local phase features. A global optimization method is applied based on the traditional iterative closest point registration algorithm, which is robust to initialization. The International Society of Biomechanics recommended joint kinematics descriptor has been adapted to calculate the joint kinematics. The developed system prototype has been validated with a ball-joint femoral phantom and tested in vivo with 10 volunteers. The maximum Euclidean distance error of the automatic bone segmentation is less than 2 pixels (approximately 0.2 mm). The maximum absolute rotation angle error is less than [Formula: see text]. This computer-aided tracking and motion analysis with ultrasound (CAT & MAUS) system shows the feasibility of describing hip joint kinematics for clinical investigation and diagnosis using an image-based solution.



    Teerawong Laosuwan; Torsak Gomasathit; Tanutdech Rotjanakusol


    This research aimed to present the technique for land surface temperature analysis with the data from Landsat-8 Operational Land Imager (OLI) /Thermal Infrared Sensors (TIR) in Meuang Maha Sarakham District, Maha Sarakham Province, Northeastern, Thailand. The research was conducted as following three steps: 1) Collecting the satellite data in thermal infrared band from Landsat-8 TIR satellite to adjust the value of Top of Atmosphere (ToA) Reflectance and then analyzing the land surface temper...

  4. An operational analysis of Lake Surface Water Temperature

    Directory of Open Access Journals (Sweden)

    Emma K. Fiedler


    Full Text Available Operational analyses of Lake Surface Water Temperature (LSWT have many potential uses including improvement of numerical weather prediction (NWP models on regional scales. In November 2011, LSWT was included in the Met Office Operational Sea Surface Temperature and Ice Analysis (OSTIA product, for 248 lakes globally. The OSTIA analysis procedure, which has been optimised for oceans, has also been used for the lakes in this first version of the product. Infra-red satellite observations of lakes and in situ measurements are assimilated. The satellite observations are based on retrievals optimised for Sea Surface Temperature (SST which, although they may introduce inaccuracies into the LSWT data, are currently the only near-real-time information available. The LSWT analysis has a global root mean square difference of 1.31 K and a mean difference of 0.65 K (including a cool skin effect of 0.2 K compared to independent data from the ESA ARC-Lake project for a 3-month period (June to August 2009. It is demonstrated that the OSTIA LSWT is an improvement over the use of climatology to capture the day-to-day variation in global lake surface temperatures.

  5. Modeling high temperature materials behavior for structural analysis

    CERN Document Server

    Naumenko, Konstantin


    This monograph presents approaches to characterize inelastic behavior of materials and structures at high temperature. Starting from experimental observations, it discusses basic features of inelastic phenomena including creep, plasticity, relaxation, low cycle and thermal fatigue. The authors formulate constitutive equations to describe the inelastic response for the given states of stress and microstructure. They introduce evolution equations to capture hardening, recovery, softening, ageing and damage processes. Principles of continuum mechanics and thermodynamics are presented to provide a framework for the modeling materials behavior with the aim of structural analysis of high-temperature engineering components.

  6. Seal Joint Analysis and Design for the Ares-I Upper Stage LOX Tank (United States)

    Phillips, Dawn R.; Wingate, Robert J.


    The sealing capability of the Ares-I Upper Stage liquid oxygen tank-to-sump joint is assessed by analyzing the deflections of the joint components. Analyses are performed using three-dimensional symmetric wedge finite element models and the ABAQUS commercial finite element software. For the pressure loads and feedline interface loads, the analyses employ a mixed factor of safety approach to comply with the Constellation Program factor of safety requirements. Naflex pressure-assisted seals are considered first because they have been used successfully in similar seal joints in the Space Shuttle External Tank. For the baseline sump seal joint configuration with a Naflex seal, the predicted joint opening greatly exceeds the seal design specification. Three redesign options of the joint that maintain the use of a Naflex seal are studied. The joint openings for the redesigned seal joints show improvement over the baseline configuration; however, these joint openings still exceed the seal design specification. RACO pressure-assisted seals are considered next because they are known to also be used on the Space Shuttle External Tank, and the joint opening allowable is much larger than the specification for the Naflex seals. The finite element models for the RACO seal analyses are created by modifying the models that were used for the Naflex seal analyses. The analyses show that the RACO seal may provide sufficient sealing capability for the sump seal joint. The results provide reasonable data to recommend the design change and plan a testing program to determine the capability of RACO seals in the Ares-I Upper Stage liquid oxygen tank sump seal joint.

  7. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method


    Dariusz Ulbrich; Jakub Kowalczyk; Marian Jósko; Jarosław Selech


    Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel shee...

  8. Bayesian nonparametric mixed-effects joint model for longitudinal-competing risks data analysis in presence of multiple data features. (United States)

    Lu, Tao


    Recently, the joint analysis of longitudinal and survival data has been an active research area. Most joint models focus on survival data with only one type of failure. The research on joint modeling of longitudinal and competing risks survival data is sparse. Even so, many joint models for this type of data assume parametric function forms for both longitudinal and survival sub-models, thus limits their use. Further, the common data features that are usually observed in practice, such as asymmetric distribution and missingness in response, measurement errors in covariate, need to be taken into account for reliable parameter estimation. The statistical inference is complicated when all these factors are considered simultaneously. In the article, driven by a motivating example, we assume nonparametric function forms for the varying coefficients in both longitudinal and competing risks survival sub-models. We propose a Bayesian nonparametric mixed-effects joint model for the analysis of longitudinal-competing risks data with asymmetry, missingness, and measurement errors. Simulation studies are conducted to assess the performance of the proposed method. We apply the proposed method to an AIDS dataset and compare a few candidate models under various settings. Some interesting results are reported.

  9. Analysis of polyethylene terephthalate PET plastic bottle jointing system using finite element method (FEM) (United States)

    Zaidi, N. A.; Rosli, Muhamad Farizuan; Effendi, M. S. M.; Abdullah, Mohamad Hariri


    For almost all injection molding applications of Polyethylene Terephthalate (PET) plastic was analyzed the strength, durability and stiffness of properties by using Finite Element Method (FEM) for jointing system of wood furniture. The FEM was utilized for analyzing the PET jointing system for Oak and Pine as wood based material of furniture. The difference pattern design of PET as wood jointing furniture gives the difference value of strength furniture itself. The results show the wood specimen with grooves and eclipse pattern design PET jointing give lower global estimated error is 28.90%, compare to the rectangular and non-grooves wood specimen of global estimated error is 63.21%.

  10. DEM analysis of the effect of joint geometry on the shear behavior of rocks (United States)

    Jiang, Mingjing; Liu, Jun; Crosta, Giovanni B.; Li, Tao


    In order to comprehensively investigate the effect of different joint geometries on the shear behavior of rocks, the Distinct Element Method (DEM) was utilized with a new bond contact model. A series of direct shear tests on coplanar and non-coplanar jointed rocks was simulated using the PFC2D software, which incorporates our bond contact model. Both coplanar jointed rocks with different joint persistence and non-coplanar ones with different joint inclinations were simulated and investigated numerically. The numerical results were compared and discussed with relevant laboratory tests as well as some reported numerical works. The results show that for coplanar jointed rocks, the peak shear stress decreases nonlinearly with the joint persistence, and the failure process can be divided into four stages: elastic shearing phase, crack propagation, failure of rock bridges, and residual phase. For non-coplanar jointed rocks, as the absolute value of the inclination angle of the rock joints increases, its shear strength increases, changing the failure patterns and the length of new fractures between existing cracks. When the absolute value increases from 15° to 30°, the average shear capacity increases the most as 39%, while the shear capacity increases the least as 2.9% when the absolute value changes from 45° to 60°. There is a good consistency of the failure patterns obtained from experiments and numerical tests. All these demonstrate that the DEM can be further applied to rock mechanics and practical rock engineering with confidence in the future.

  11. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method

    Directory of Open Access Journals (Sweden)

    Dariusz Ulbrich


    Full Text Available Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel sheet, which could be used in factories employing such joints. In addition, the article makes comparison between the costs of the developed assessment technique and currently used destructive method.

  12. Analysis and multiclass classification of pathological knee joints using vibroarthrographic signals. (United States)

    Kręcisz, Krzysztof; Bączkowicz, Dawid


    Vibroarthrography (VAG) is a method developed for sensitive and objective assessment of articular function. Although the VAG method is still in development, it shows high accuracy, sensitivity and specificity when comparing results obtained from controls and the non-specific, knee-related disorder group. However, the multiclass classification remains practically unknown. Therefore the aim of this study was to extend the VAG method classification to 5 classes, according to different disorders of the patellofemoral joint. We assessed 121 knees of patients (95 knees with grade I-III chondromalacia patellae, 26 with osteoarthritis) and 66 knees from 33 healthy controls. The vibroarthrographic signals were collected during knee flexion/extension motion using an acceleration sensor. The genetic search algorithm was chosen to select the most relevant features of the VAG signal for classification. Four different algorithms were used for classification of selected features: logistic regression with automatic attribute selection (SimpleLogistic in Weka), multilayer perceptron with sigmoid activation function (MultilayerPerceptron), John Platt's sequential minimal optimization algorithm implementation of support vector classifier (SMO) and random forest tree (RandomForest). The generalization error of classification algorithms was evaluated by stratified 10-fold cross-validation. We obtained levels of accuracy and AUC metrics over 90%, more than 93% sensitivity and more than 84% specificity for the logistic regression-based method (SimpleLogistic) for a 2-class classification. For the 5-class method, we obtained 69% and 90% accuracy and AUC respectively, and sensitivity and specificity over 91% and 69%. The results of this study confirm the high usefulness of quantitative analysis of VAG signals based on classification techniques into normal and pathological knees and as a promising tool in classifying signals of various knee joint disorders and their stages. Copyright

  13. Joint linkage and association analysis with exome sequence data implicates SLC25A40 in hypertriglyceridemia. (United States)

    Rosenthal, Elisabeth A; Ranchalis, Jane; Crosslin, David R; Burt, Amber; Brunzell, John D; Motulsky, Arno G; Nickerson, Deborah A; Wijsman, Ellen M; Jarvik, Gail P


    Hypertriglyceridemia (HTG) is a heritable risk factor for cardiovascular disease. Investigating the genetics of HTG may identify new drug targets. There are ~35 known single-nucleotide variants (SNVs) that explain only ~10% of variation in triglyceride (TG) level. Because of the genetic heterogeneity of HTG, a family study design is optimal for identification of rare genetic variants with large effect size because the same mutation can be observed in many relatives and cosegregation with TG can be tested. We considered HTG in a five-generation family of European American descent (n = 121), ascertained for familial combined hyperlipidemia. By using Bayesian Markov chain Monte Carlo joint oligogenic linkage and association analysis, we detected linkage to chromosomes 7 and 17. Whole-exome sequence data revealed shared, highly conserved, private missense SNVs in both SLC25A40 on chr7 and PLD2 on chr17. Jointly, these SNVs explained 49% of the genetic variance in TG; however, only the SLC25A40 SNV was significantly associated with TG (p = 0.0001). This SNV, c.374A>G, causes a highly disruptive p.Tyr125Cys substitution just outside the second helical transmembrane region of the SLC25A40 inner mitochondrial membrane transport protein. Whole-gene testing in subjects from the Exome Sequencing Project confirmed the association between TG and SLC25A40 rare, highly conserved, coding variants (p = 0.03). These results suggest a previously undescribed pathway for HTG and illustrate the power of large pedigrees in the search for rare, causal variants. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  14. International joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig


    The article analysis problems connected with corporate joint ventures. Among others the possible conflicts between the joint venture agreement and the statutes of the companies is examined, as well as certain problems connected to the fact that the joint venture partners have created commen contr...

  15. Bridges Expansion Joints


    Sergey W. Kozlachkow


    The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  16. Analysis of Low Temperature Organic Rankine Cycles for Solar Applications (United States)

    Li, Yunfei

    The present work focuses on Organic Rankine Cycle (ORC) systems and their application to low temperature waste heat recovery, combined heat and power as well as off-grid solar power generation applications. As CO_2 issues come to the fore front and fossil fuels become more expensive, interest in low grade heat recovery has grown dramatically in the past few years. Solar energy, as a clean, renewable, pollution-free and sustainable energy has great potential for the use of ORC systems. Several ORC solutions have been proposed to generate electricity from low temperature sources. The ORC systems discussed here can be applied to fields such as solar thermal, biological waste heat, engine exhaust gases, small-scale cogeneration, domestic boilers, etc. The current work presents a thermodynamic and economic analysis for the use of ORC systems to convert solar energy or low exergy energy to generate electrical power. The organic working fluids investigated here were selected to investigate the effect of the fluid saturation temperature on the performance of ORCs. The working fluids under investigation are R113, R245fa, R123, with boiling points between 40°C and 200°C at pressures from 10 kPa to 10 MPa. Ambient temperature air at 20oC to 30oC is utilized as cooling resource, and allowing for a temperature difference 10°C for effective heat transfer. Consequently, the working fluids are condensed at 40°C. A combined first- and second-law analysis is performed by varying some system independent parameters at various reference temperatures. The present work shows that ORC systems can be viable and economical for the applications such as waste heat use and off-grid power generation even though they are likely to be more expensive than grid power.

  17. Monitoring Across Borders: 2010 Joint Meeting of the Forest Inventory and Analysis (FIA) Symposium and the Southern Mensurationists (United States)

    Will McWilliams; Francis A. Roesch


    These proceedings represent the range of topics covered during the 2010 Joint Meeting of the Forest Inventory and Analysis (FIA) Symposium and the Southern Mensurationists, October 5-7, 2010 in Knoxville, TN. The meeting was a gathering of forest scientists with a quantitative leaning and, as such, the papers discuss the aspects of the observation, estimation, modeling...

  18. A Model-Based Approach for Joint Analysis of Pain Intensity and Opioid Consumption in Postoperative Pain

    DEFF Research Database (Denmark)

    Juul, Rasmus V; Knøsgaard, Katrine R; Olesen, Anne E


    intensity and opioid consumption in a 4-h postoperative period for 44 patients undergoing percutaneous kidney stone surgery. Analysis was based on 748 Numerical Rating Scale (NRS) scores of pain intensity and 51 observed morphine and oxycodone dosing events. A joint model was developed to describe...

  19. An analysis of spatial representativeness of air temperature monitoring stations (United States)

    Liu, Suhua; Su, Hongbo; Tian, Jing; Wang, Weizhen


    Surface air temperature is an essential variable for monitoring the atmosphere, and it is generally acquired at meteorological stations that can provide information about only a small area within an r m radius (r-neighborhood) of the station, which is called the representable radius. In studies on a local scale, ground-based observations of surface air temperatures obtained from scattered stations are usually interpolated using a variety of methods without ascertaining their effectiveness. Thus, it is necessary to evaluate the spatial representativeness of ground-based observations of surface air temperature before conducting studies on a local scale. The present study used remote sensing data to estimate the spatial distribution of surface air temperature using the advection-energy balance for air temperature (ADEBAT) model. Two target stations in the study area were selected to conduct an analysis of spatial representativeness. The results showed that one station (AWS 7) had a representable radius of about 400 m with a possible error of less than 1 K, while the other station (AWS 16) had the radius of about 250 m. The representable radius was large when the heterogeneity of land cover around the station was small.

  20. Kinect as a Tool for Gait Analysis: Validation of a Real-Time Joint Extraction Algorithm Working in Side View


    Enea Cippitelli; Samuele Gasparrini; Susanna Spinsante; Ennio Gambi


    The Microsoft Kinect sensor has gained attention as a tool for gait analysis for several years. Despite the many advantages the sensor provides, however, the lack of a native capability to extract joints from the side view of a human body still limits the adoption of the device to a number of relevant applications. This paper presents an algorithm to locate and estimate the trajectories of up to six joints extracted from the side depth view of a human body captured by the Kinect device. The a...

  1. Design, Analysis and Testing of a PRSEUS Pressure Cube to Investigate Assembly Joints (United States)

    Yovanof, Nicolette; Lovejoy, Andrew E.; Baraja, Jaime; Gould, Kevin


    Due to its potential to significantly increase fuel efficiency, the current focus of NASA's Environmentally Responsible Aviation Program is the hybrid wing body (HWB) aircraft. Due to the complex load condition that exists in HWB structure, as compared to traditional aircraft configurations, light-weight, cost-effective and manufacturable structural concepts are required to enable the HWB. The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept is one such structural concept. A building block approach for technology development of the PRSEUS concept is being conducted. As part of this approach, a PRSEUS pressure cube was developed as a risk reduction test article to examine a new integral cap joint concept. This paper describes the design, analysis and testing of the PRSEUS pressure cube test article. The pressure cube was required to withstand a 2P, 18.4 psi, overpressure load requirement. The pristine pressure cube was tested to 2.2P with no catastrophic failure. After the addition of barely visible impact damage, the cube was pressure loaded to 48 psi where catastrophic failure occurred, meeting the scale-up requirement. Comparison of pretest and posttest analyses with the cube test response agree well, and indicate that current analysis methods can be used to accurately analyze PRSEUS structure for initial failure response.

  2. Computer-assisted 3D kinematic analysis of all leg joints in walking insects.

    Directory of Open Access Journals (Sweden)

    John A Bender

    Full Text Available High-speed video can provide fine-scaled analysis of animal behavior. However, extracting behavioral data from video sequences is a time-consuming, tedious, subjective task. These issues are exacerbated where accurate behavioral descriptions require analysis of multiple points in three dimensions. We describe a new computer program written to assist a user in simultaneously extracting three-dimensional kinematics of multiple points on each of an insect's six legs. Digital video of a walking cockroach was collected in grayscale at 500 fps from two synchronized, calibrated cameras. We improved the legs' visibility by painting white dots on the joints, similar to techniques used for digitizing human motion. Compared to manual digitization of 26 points on the legs over a single, 8-second bout of walking (or 106,496 individual 3D points, our software achieved approximately 90% of the accuracy with 10% of the labor. Our experimental design reduced the complexity of the tracking problem by tethering the insect and allowing it to walk in place on a lightly oiled glass surface, but in principle, the algorithms implemented are extensible to free walking. Our software is free and open-source, written in the free language Python and including a graphical user interface for configuration and control. We encourage collaborative enhancements to make this tool both better and widely utilized.

  3. Computer-assisted 3D kinematic analysis of all leg joints in walking insects. (United States)

    Bender, John A; Simpson, Elaine M; Ritzmann, Roy E


    High-speed video can provide fine-scaled analysis of animal behavior. However, extracting behavioral data from video sequences is a time-consuming, tedious, subjective task. These issues are exacerbated where accurate behavioral descriptions require analysis of multiple points in three dimensions. We describe a new computer program written to assist a user in simultaneously extracting three-dimensional kinematics of multiple points on each of an insect's six legs. Digital video of a walking cockroach was collected in grayscale at 500 fps from two synchronized, calibrated cameras. We improved the legs' visibility by painting white dots on the joints, similar to techniques used for digitizing human motion. Compared to manual digitization of 26 points on the legs over a single, 8-second bout of walking (or 106,496 individual 3D points), our software achieved approximately 90% of the accuracy with 10% of the labor. Our experimental design reduced the complexity of the tracking problem by tethering the insect and allowing it to walk in place on a lightly oiled glass surface, but in principle, the algorithms implemented are extensible to free walking. Our software is free and open-source, written in the free language Python and including a graphical user interface for configuration and control. We encourage collaborative enhancements to make this tool both better and widely utilized.

  4. Deregulation upon DNA damage revealed by joint analysis of context-specific perturbation data

    Directory of Open Access Journals (Sweden)

    Biecek Przemysław


    Full Text Available Abstract Background Deregulation between two different cell populations manifests itself in changing gene expression patterns and changing regulatory interactions. Accumulating knowledge about biological networks creates an opportunity to study these changes in their cellular context. Results We analyze re-wiring of regulatory networks based on cell population-specific perturbation data and knowledge about signaling pathways and their target genes. We quantify deregulation by merging regulatory signal from the two cell populations into one score. This joint approach, called JODA, proves advantageous over separate analysis of the cell populations and analysis without incorporation of knowledge. JODA is implemented and freely available in a Bioconductor package 'joda'. Conclusions Using JODA, we show wide-spread re-wiring of gene regulatory networks upon neocarzinostatin-induced DNA damage in Human cells. We recover 645 deregulated genes in thirteen functional clusters performing the rich program of response to damage. We find that the clusters contain many previously characterized neocarzinostatin target genes. We investigate connectivity between those genes, explaining their cooperation in performing the common functions. We review genes with the most extreme deregulation scores, reporting their involvement in response to DNA damage. Finally, we investigate the indirect impact of the ATM pathway on the deregulated genes, and build a hypothetical hierarchy of direct regulation. These results prove that JODA is a step forward to a systems level, mechanistic understanding of changes in gene regulation between different cell populations.

  5. Joint genetic analysis using variant sets reveals polygenic gene-context interactions.

    Directory of Open Access Journals (Sweden)

    Francesco Paolo Casale


    Full Text Available Joint genetic models for multiple traits have helped to enhance association analyses. Most existing multi-trait models have been designed to increase power for detecting associations, whereas the analysis of interactions has received considerably less attention. Here, we propose iSet, a method based on linear mixed models to test for interactions between sets of variants and environmental states or other contexts. Our model generalizes previous interaction tests and in particular provides a test for local differences in the genetic architecture between contexts. We first use simulations to validate iSet before applying the model to the analysis of genotype-environment interactions in an eQTL study. Our model retrieves a larger number of interactions than alternative methods and reveals that up to 20% of cases show context-specific configurations of causal variants. Finally, we apply iSet to test for sub-group specific genetic effects in human lipid levels in a large human cohort, where we identify a gene-sex interaction for C-reactive protein that is missed by alternative methods.

  6. Finite element analysis of artificial hip joint movement during human activities

    NARCIS (Netherlands)

    Saputra, Eko; Budiwan, I.; Jamari, Jamari; van der Heide, Emile


    The range of motion of artificial hip joint during human activities, measured from the postoperative total hip arthroplasty patients, has been reported previously. There were two human activities discussed, i.e. Western-style and Japanese-style. This paper analyzes the hip joint movement during

  7. A mixture model for the joint analysis of latent developmental trajectories and survival

    NARCIS (Netherlands)

    Klein Entink, R.H.; Fox, J.P.; Hout, A. van den


    A general joint modeling framework is proposed that includes a parametric stratified survival component for continuous time survival data, and a mixture multilevel item response component to model latent developmental trajectories given mixed discrete response data. The joint model is illustrated in

  8. The validation of a diagnostic rule for gout without joint fluid analysis: a prospective study

    NARCIS (Netherlands)

    Kienhorst, L.B.; Janssens, H.J.; Fransen, J.; Janssen, M


    OBJECTIVE: The gold standard for diagnosing gout is the identification of MSU crystals in joint fluid. In secondary care, the facilities or expertise to analyse joint fluid are not always available and gout is diagnosed clinically. To improve the predictive value of the clinical diagnosis of gout in

  9. Fabrication, testing and analysis of steel/composite DLS adhesive joints

    DEFF Research Database (Denmark)

    Nashim, S.; Nisar, J.; Tsouvalis, N.


    This paper aims to provide a guide on the design and fabrication of thick adherend double lap shear joints (DLS), often referred to as butt connections/joints in ship structures including patch repair. The specimens consist of 10mm steel inner adherend and various outer adherend materials includi...

  10. Temperature-based Instanton Analysis: Identifying Vulnerability in Transmission Networks

    Energy Technology Data Exchange (ETDEWEB)

    Kersulis, Jonas [Univ. of Michigan, Ann Arbor, MI (United States); Hiskens, Ian [Univ. of Michigan, Ann Arbor, MI (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bienstock, Daniel [Columbia Univ., New York, NY (United States)


    A time-coupled instanton method for characterizing transmission network vulnerability to wind generation fluctuation is presented. To extend prior instanton work to multiple-time-step analysis, line constraints are specified in terms of temperature rather than current. An optimization formulation is developed to express the minimum wind forecast deviation such that at least one line is driven to its thermal limit. Results are shown for an IEEE RTS-96 system with several wind-farms.

  11. Microstructure and Failure Analysis of Flash Butt Welded HSLA 590CL Steel Joints in Wheel Rims (United States)

    Lu, Ping; Xu, Zhixin; Shu, Yang; Ma, Feng


    The aim of the present investigation was to evaluate the microstructures, mechanical properties and failure behavior of flash butt welded high strength low alloy 590CL steel joints. Acicular ferrite, Widmanstatten ferrite and granular bainite were observed in the weld. The micro-hardness values of the welded joints varied between 250 HV and 310 HV. The tensile strength of the welded joints met the strength standard of the wheel steel. The Charpy V-notch impact absorbing energy of the welded joints was higher than the base metal, and the impact fracture of the welded joints was composed of shearing and equiaxed dimples. The fracture mode of the wheel rim in the flaring and expanding process was brittle fracture and ductile fracture, respectively. A limited deviation was found in the terminal of the crack for the wheel in the flaring process. A transition from the weld to the Heat Affected Zone was observed for the wheel in the expanding process.

  12. A Laboratory Study on Stress Dependency of Joint Transmissivity and its Modeling with Neural Networks, Fuzzy Method and Regression Analysis

    Directory of Open Access Journals (Sweden)

    Amin Moori Roozali


    Full Text Available Correct estimation of water inflow into underground excavations can decrease safety risks and associated costs. Researchers have proposed different methods to asses this value. It has been proved that water transmissivity of a rock joint is a function of factors, such as normal stress, joint roughness and its size and water pressure therefore, a laboratory setup was proposed to quantitatively measure the flow as a function of mentioned parameters. Among these, normal stress has proved to be the most influential parameter. With increasing joint roughness and rock sample size, water flow has decreased while increasing water pressure has a direct increasing effect on the flow. To simulate the complex interaction of these parameters, neural networks and Fuzzy method together with regression analysis have been utilized. Correlation factors between laboratory results and obtained numerical ones show good agreement which proves usefulness of these methods for assessment of water inflow.

  13. Influence of weak hip abductor muscles on joint contact forces during normal walking: probabilistic modeling analysis. (United States)

    Valente, Giordano; Taddei, Fulvia; Jonkers, Ilse


    The weakness of hip abductor muscles is related to lower-limb joint osteoarthritis, and joint overloading may increase the risk for disease progression. The relationship between muscle strength, structural joint deterioration and joint loading makes the latter an important parameter in the study of onset and follow-up of the disease. Since the relationship between hip abductor weakness and joint loading still remains an open question, the purpose of this study was to adopt a probabilistic modeling approach to give insights into how the weakness of hip abductor muscles, in the extent to which normal gait could be unaltered, affects ipsilateral joint contact forces. A generic musculoskeletal model was scaled to each healthy subject included in the study, and the maximum force-generating capacity of each hip abductor muscle in the model was perturbed to evaluate how all physiologically possible configurations of hip abductor weakness affected the joint contact forces during walking. In general, the muscular system was able to compensate for abductor weakness. The reduced force-generating capacity of the abductor muscles affected joint contact forces to a mild extent, with 50th percentile mean differences up to 0.5 BW (maximum 1.7 BW). There were greater increases in the peak knee joint loads than in loads at the hip or ankle. Gluteus medius, particularly the anterior compartment, was the abductor muscle with the most influence on hip and knee loads. Further studies should assess if these increases in joint loading may affect initiation and progression of osteoarthritis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Error analysis for mesospheric temperature profiling by absorptive occultation sensors

    Directory of Open Access Journals (Sweden)

    M. J. Rieder

    Full Text Available An error analysis for mesospheric profiles retrieved from absorptive occultation data has been performed, starting with realistic error assumptions as would apply to intensity data collected by available high-precision UV photodiode sensors. Propagation of statistical errors was investigated through the complete retrieval chain from measured intensity profiles to atmospheric density, pressure, and temperature profiles. We assumed unbiased errors as the occultation method is essentially self-calibrating and straight-line propagation of occulted signals as we focus on heights of 50–100 km, where refractive bending of the sensed radiation is negligible. Throughout the analysis the errors were characterized at each retrieval step by their mean profile, their covariance matrix and their probability density function (pdf. This furnishes, compared to a variance-only estimation, a much improved insight into the error propagation mechanism. We applied the procedure to a baseline analysis of the performance of a recently proposed solar UV occultation sensor (SMAS – Sun Monitor and Atmospheric Sounder and provide, using a reasonable exponential atmospheric model as background, results on error standard deviations and error correlation functions of density, pressure, and temperature profiles. Two different sensor photodiode assumptions are discussed, respectively, diamond diodes (DD with 0.03% and silicon diodes (SD with 0.1% (unattenuated intensity measurement noise at 10 Hz sampling rate. A factor-of-2 margin was applied to these noise values in order to roughly account for unmodeled cross section uncertainties. Within the entire height domain (50–100 km we find temperature to be retrieved to better than 0.3 K (DD / 1 K (SD accuracy, respectively, at 2 km height resolution. The results indicate that absorptive occultations acquired by a SMAS-type sensor could provide mesospheric profiles of fundamental variables such as temperature with

  15. Preliminary bolted-joint data (United States)

    Wichorek, G. R.


    Bolted-joint strength and failure modes for advanced graphite/polyimide composite laminates at 116K (-250 F), room temperature, and 589K (600 F) were determined to provide preliminary design data. The bolted-joint test setup for the low and elevated temperature tests is described. Test results are reported on a quasi-isotropic laminate of Celion 6000/PMR-15. Single bolt, double lap shear specimens were tested to obtain maximum joint strength and failure mode. The effect of joint geometry and temperature on joint strength and failure mode is presented.

  16. Analysis of slot cutting methods for the Yucca Mountain heated block test using a compliant-joint model

    Energy Technology Data Exchange (ETDEWEB)

    Chen, E.P.; Costin, L.S.


    Pretest analysis of a heated block test, proposed for the Exploratory Studies Facility at Yucca Mountain, Nevada, was conducted in this investigation. Specifically, the study focuses on the evaluation of the various designs to drill holes and cut slots for the block. The thermal/mechanical analysis was based on the finite element method and a compliant-joint rock-mass constitutive model. Based on the calculated results, relative merits of the various test designs are discussed.

  17. Gaussian anamorphosis in the analysis step of the EnKF: a joint state-variable/observation approach

    Directory of Open Access Journals (Sweden)

    Javier Amezcua


    Full Text Available The analysis step of the (ensemble Kalman filter is optimal when (1 the distribution of the background is Gaussian, (2 state variables and observations are related via a linear operator, and (3 the observational error is of additive nature and has Gaussian distribution. When these conditions are largely violated, a pre-processing step known as Gaussian anamorphosis (GA can be applied. The objective of this procedure is to obtain state variables and observations that better fulfil the Gaussianity conditions in some sense. In this work we analyse GA from a joint perspective, paying attention to the effects of transformations in the joint state-variable/observation space. First, we study transformations for state variables and observations that are independent from each other. Then, we introduce a targeted joint transformation with the objective to obtain joint Gaussianity in the transformed space. We focus primarily in the univariate case, and briefly comment on the multivariate one. A key point of this paper is that, when (1–(3 are violated, using the analysis step of the EnKF will not recover the exact posterior density in spite of any transformations one may perform. These transformations, however, provide approximations of different quality to the Bayesian solution of the problem. Using an example in which the Bayesian posterior can be analytically computed, we assess the quality of the analysis distributions generated after applying the EnKF analysis step in conjunction with different GA options. The value of the targeted joint transformation is particularly clear for the case when the prior is Gaussian, the marginal density for the observations is close to Gaussian, and the likelihood is a Gaussian mixture.

  18. A joint econometric analysis of seat belt use and crash-related injury severity. (United States)

    Eluru, Naveen; Bhat, Chandra R


    This paper formulates a comprehensive econometric structure that recognizes two important issues in crash-related injury severity analysis. First, the impact of a factor on injury severity may be moderated by various observed and unobserved variables specific to an individual or to a crash. Second, seat belt use is likely to be endogenous to injury severity. That is, it is possible that intrinsically unsafe drivers do not wear seat belts and are the ones likely to be involved in high injury severity crashes because of their unsafe driving habits. The preceding issues are considered in the current research effort through the development of a comprehensive model of seat belt use and injury severity that takes the form of a joint correlated random coefficients binary-ordered response system. To our knowledge, this is the first instance of such a model formulation and application not only in the safety analysis literature, but in the econometrics literature in general. The empirical analysis is based on the 2003 General Estimates System (GES) data base. Several types of variables are considered to explain seat belt use and injury severity levels, including driver characteristics, vehicle characteristics, roadway design attributes, environmental factors, and crash characteristics. The results, in addition to confirming the effects of various explanatory variables, also highlight the importance of (a) considering the moderating effects of unobserved individual/crash-related factors on the determinants of injury severity and (b) seat belt use endogeneity. From a policy standpoint, the results suggest that seat belt non-users, when apprehended in the act, should perhaps be subjected to both a fine (to increase the chances that they wear seat belts) as well as mandatory enrollment in a defensive driving course (to attempt to change their aggressive driving behaviors).

  19. A joint analysis of Planck and BICEP2 B modes including dust polarization uncertainty (United States)

    Mortonson, Michael J.; Seljak, Uroš


    We analyze BICEP2 and Planck data using a model that includes CMB lensing, gravity waves, and polarized dust. Recently published Planck dust polarization maps have highlighted the difficulty of estimating the amount of dust polarization in low intensity regions, suggesting that the polarization fractions have considerable uncertainties and may be significantly higher than previous predictions. In this paper, we start by assuming nothing about the dust polarization except for the power spectrum shape, which we take to be ClBB,dust propto l-2.42. The resulting joint BICEP2+Planck analysis favors solutions without gravity waves, and the upper limit on the tensor-to-scalar ratio is r0.14 are excluded with 99.5% confidence). We address the cross-correlation analysis of BICEP2 at 150 GHz with BICEP1 at 100 GHz as a test of foreground contamination. We find that the null hypothesis of dust and lensing with 0r= gives Δ χ2 < 2 relative to the hypothesis of no dust, so the frequency analysis does not strongly favor either model over the other. We also discuss how more accurate dust polarization maps may improve our constraints. If the dust polarization is measured perfectly, the limit can reach r < 0.05 (or the corresponding detection significance if the observed dust signal plus the expected lensing signal is below the BICEP2 observations), but this degrades quickly to almost no improvement if the dust calibration error is 20% or larger or if the dust maps are not processed through the BICEP2 pipeline, inducing sampling variance noise.

  20. Bridges Expansion Joints

    National Research Council Canada - National Science Library

    Sergey W. Kozlachkow


    .... The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting...

  1. Rapid formation of Ni3Sn4 joints for die attachment of SiC-based high temperature power devices using ultrasound-induced transient liquid phase bonding process. (United States)

    Li, Z L; Dong, H J; Song, X G; Zhao, H Y; Feng, J C; Liu, J H; Tian, H; Wang, S J


    High melting point Ni3Sn4 joints for the die attachment of SiC-based high temperature power devices was successfully achieved using an ultrasound-induced transient liquid phase (TLP) bonding process within a remarkably short bonding time of 8s. The formed intermetallic joints, which are completely composed of the refined equiaxial Ni3Sn4 grains with the average diameter of 2μm, perform the average shear strength of 26.7MPa. The sonochemical effects of ultrasonic waves dominate the mechanism and kinetics of the rapid formation of Ni3Sn4 joints. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Global-Local Finite Element Analysis of Bonded Single-Lap Joints (United States)

    Kilic, Bahattin; Madenci, Erdogan; Ambur, Damodar R.


    Adhesively bonded lap joints involve dissimilar material junctions and sharp changes in geometry, possibly leading to premature failure. Although the finite element method is well suited to model the bonded lap joints, traditional finite elements are incapable of correctly resolving the stress state at junctions of dissimilar materials because of the unbounded nature of the stresses. In order to facilitate the use of bonded lap joints in future structures, this study presents a finite element technique utilizing a global (special) element coupled with traditional elements. The global element includes the singular behavior at the junction of dissimilar materials with or without traction-free surfaces.

  3. A custom-made temporomandibular joint prosthesis for fabrication by selective laser melting: Finite element analysis. (United States)

    Xu, Xiangliang; Luo, Danmei; Guo, Chuanbin; Rong, Qiguo


    A novel and custom-made selective laser melting (SLM) 3D-printed alloplastic temporomandibular joint (TMJ) prosthesis is proposed. The titanium-6aluminium-4vanadium (Ti-6Al-4V) condyle component and ultra-high molecular weight polyethylene (UHMWPE) fossa component comprised the total alloplastic TMJ replacement prosthesis. For the condyle component, an optimized tetrahedral open-porous scaffold with combined connection structures, i.e. an inlay rod and an onlay plate, between the prosthesis and remaining mandible was designed. The trajectory of movement of the intact condyle was assessed via kinematic analysis to facilitate the design of the fossa component. The behaviours of the intact mandible and mandible with the prosthesis were compared. The biomechanical behaviour was analysed by assessing the stress distribution on the prosthesis and strain distribution on the mandible. After muscle force was applied, the magnitude of the compressive strain on the condyle neck of the mandible with the prosthesis was lower than that on the condyle neck of the intact mandible, with the exception of the area about the screws; additionally, the magnitude of the strain at the scaffold-bone interface was relatively high. Copyright © 2017. Published by Elsevier Ltd.

  4. Fracture testing and analysis of adhesively bonded joints for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Boeman, R.G.; Warren, C.D. [Oak Ridge National Lab., TN (United States). Engineering Technology Div.


    In 1992, the Oak Ridge National Laboratory (ORNL) began a cooperative effort with the Automotive Composites Consortium (ACC) to conduct research and development that would overcome technological hurdles to the adhesive bonding of current and future automotive materials. This effort is part of a larger Department of Energy (DOE) program to promote the use of lighter weight materials in automotive structures for the purpose of increasing fuel efficiency and reducing environmental pollutant emissions. In accomplishing this mission, the bonding of similar and dissimilar materials was identified as being of primary importance to the automotive industry since this enabling technology would give designers the freedom to choose from an expanded menu of low mass materials for component weight reduction. This paper concentrates on the details of developing accurate fracture test methods for adhesively bonded joints in the automotive industry. The test methods being developed are highly standardized and automated so that industry suppliers will be able to pass on reliable data to automotive designers in a timely manner. Mode I fracture tests have been developed that are user friendly and automated for easy data acquisition, data analysis, test control and test repeatability. The development of this test is discussed. In addition, materials and manufacturing issues are addressed which are of particular importance when designing adhesive and composite material systems.

  5. Evaluation on joint toxicity of chlorinated anilines and cadmium to Photobacterium phosphoreum and QSAR analysis. (United States)

    Jin, Hao; Wang, Chao; Shi, Jiaqi; Chen, Lei


    The individual IC50 (the concentrations causing a 50% inhibition of bioluminescence after 15min exposure) of cadmium ion (Cd) and nine chlorinated anilines to Photobacterium phosphoreum (P. phosphoreum) were determined. In order to evaluate the combined effects of the nine chlorinated anilines and Cd, the toxicities of chlorinated anilines combined with different concentrations of Cd were determined, respectively. The results showed that the number of chlorinated anilines manifesting synergy with Cd decreased with the increasing Cd concentration, and the number manifesting antagonism decreased firstly and then increased. The joint toxicity of mixtures at low Cd concentration was weaker than that of most binary mixtures when combined with Cd at medium and high concentrations as indicated by TUTotal. QSAR analysis showed that the single toxicity of chlorinated anilines was related to the energy of the lowest unoccupied molecular orbital (ELUMO). When combined with different concentrations of Cd, the toxicity was related to the energy difference (EHOMO-ELUMO) with different coefficients. Van der Waals' force or the complexation between chlorinated anilines and Cd had an impact on the toxicity of combined systems, which could account for QSAR models with different physico-chemical descriptors. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Stratosphere/troposphere joint variability in southern South America as estimated from a principal components analysis (United States)

    Yuchechen, Adrián E.; Canziani, Pablo O.; Bischoff, Susana A.


    To understand how the tropopause annual evolution relates to the troposphere and lower stratosphere over southern South America, the study analyzes the joint behavior of single and double thermal tropopauses with the 500 and 100 hPa levels in the region. Radiosonde data spanning the period 1973-2014 were used. Geopotential height time series that were filtered known cycles were used as input for an unrotated S-mode principal components analysis. The first three leading modes of variability were analyzed. The first one has a strong semi-annual behavior, linked to wind cycles, with maximum activity in the center of the study region on the lee of the Andes. It appears to be linked to the vertical propagation of planetary and gravity waves. Semi-annual and terannual cycles dominate the second mode, the associated spatial patterns having strong resemblance with the occurrence of cold fronts. The annual time series for the third mode are coupled to a blocking index over the South Atlantic, and the associated spatial structures are also similar to blocking patterns. Results are in good agreement with observations, showing that the use of thermal tropopauses is a valid tool for studying different phenomena taking place in the region.

  7. Cardiovascular coupling during graded postural challenge: comparison between linear tools and joint symbolic analysis

    Directory of Open Access Journals (Sweden)

    Alberto Porta


    Full Text Available ABSTRACT Background A joint symbolic analysis (JSA is applied to assess the strength of the cardiovascular coupling from spontaneous beat-to-beat variability of the heart period (HP and the systolic arterial pressure (SAP during an experimental protocol inducing a gradual baroreflex unloading evoked by postural change (i.e. graded head-up tilt. Method: The adopted JSA can quantify the degree of association between the HP and SAP variabilities as a function of the time scale of the HP and SAP patterns. Traditional linear tools assessing the HP-SAP coupling strength, such as squared correlation coefficient, squared coherence function, and percentage of baroreflex sequences, were computed as well for comparison. Results: We found that: i JSA indicated that the strength of the cardiovascular coupling at slow temporal scales gradually increased with the magnitude of the orthostatic challenge, while that at fast temporal scales gradually decreased; ii the squared correlation coefficient and percentage of baroreflex sequences did not detect this behavior; iii even though squared coherence function could measure the magnitude of the HP-SAP coupling as a function of the time scale, it was less powerful than JSA owing to the larger dispersion of the frequency domain indexes. Conclusion: Due to its peculiar features and high statistical power, JSA deserves applications to pathological groups in which the link between HP and SAP variabilities is lost or decreased due to the overall depression or impairment of the cardiovascular control.

  8. The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xueqin [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); School of Social Development and Public Policy, Beijing Normal University, Beijing 100875 (China); Li, Ning [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); Yuan, Shuai, E-mail: [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); Xu, Ning; Shi, Wenqin; Chen, Weibin [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China)


    As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54 years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10 years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. - Highlights: • A method to estimate the multidimensional joint return periods is presented. • 2D function allows better fitting results at the lower tail of hazard factors. • Three-dimensional simulation has obvious advantages in extreme value fitting. • Joint return periods are closer to the reality

  9. Parametric analysis of temperature gradient across thermoelectric power generators

    Directory of Open Access Journals (Sweden)

    Khaled Chahine


    Full Text Available This paper presents a parametric analysis of power generation from thermoelectric generators (TEGs. The aim of the parametric analysis is to provide recommendations with respect to the applications of TEGs. To proceed, the one-dimensional steady-state solution of the heat diffusion equation is considered with various boundary conditions representing real encountered cases. Four configurations are tested. The first configuration corresponds to the TEG heated with constant temperature at its lower surface and cooled with a fluid at its upper surface. The second configuration corresponds to the TEG heated with constant heat flux at its lower surface and cooled with a fluid at its upper surface. The third configuration corresponds to the TEG heated with constant heat flux at its lower surface and cooled by a constant temperature at its upper surface. The fourth configuration corresponds to the TEG heated by a fluid at its lower surface and cooled by a fluid at its upper surface. It was shown that the most promising configuration is the fourth one and temperature differences up to 70˚C can be achieved at 150˚C heat source. Finally, a new concept is implemented based on configuration four and tested experimentally.

  10. Kinect as a tool for gait analysis: validation of a real-time joint extraction algorithm working in side view. (United States)

    Cippitelli, Enea; Gasparrini, Samuele; Spinsante, Susanna; Gambi, Ennio


    The Microsoft Kinect sensor has gained attention as a tool for gait analysis for several years. Despite the many advantages the sensor provides, however, the lack of a native capability to extract joints from the side view of a human body still limits the adoption of the device to a number of relevant applications. This paper presents an algorithm to locate and estimate the trajectories of up to six joints extracted from the side depth view of a human body captured by the Kinect device. The algorithm is then applied to extract data that can be exploited to provide an objective score for the "Get Up and Go Test", which is typically adopted for gait analysis in rehabilitation fields. Starting from the depth-data stream provided by the Microsoft Kinect sensor, the proposed algorithm relies on anthropometric models only, to locate and identify the positions of the joints. Differently from machine learning approaches, this solution avoids complex computations, which usually require significant resources. The reliability of the information about the joint position output by the algorithm is evaluated by comparison to a marker-based system. Tests show that the trajectories extracted by the proposed algorithm adhere to the reference curves better than the ones obtained from the skeleton generated by the native applications provided within the Microsoft Kinect (Microsoft Corporation, Redmond,WA, USA, 2013) and OpenNI (OpenNI organization, Tel Aviv, Israel, 2013) Software Development Kits.

  11. Kinect as a Tool for Gait Analysis: Validation of a Real-Time Joint Extraction Algorithm Working in Side View

    Directory of Open Access Journals (Sweden)

    Enea Cippitelli


    Full Text Available The Microsoft Kinect sensor has gained attention as a tool for gait analysis for several years. Despite the many advantages the sensor provides, however, the lack of a native capability to extract joints from the side view of a human body still limits the adoption of the device to a number of relevant applications. This paper presents an algorithm to locate and estimate the trajectories of up to six joints extracted from the side depth view of a human body captured by the Kinect device. The algorithm is then applied to extract data that can be exploited to provide an objective score for the “Get Up and Go Test”, which is typically adopted for gait analysis in rehabilitation fields. Starting from the depth-data stream provided by the Microsoft Kinect sensor, the proposed algorithm relies on anthropometric models only, to locate and identify the positions of the joints. Differently from machine learning approaches, this solution avoids complex computations, which usually require significant resources. The reliability of the information about the joint position output by the algorithm is evaluated by comparison to a marker-based system. Tests show that the trajectories extracted by the proposed algorithm adhere to the reference curves better than the ones obtained from the skeleton generated by the native applications provided within the Microsoft Kinect (Microsoft Corporation, Redmond,WA, USA, 2013 and OpenNI (OpenNI organization, Tel Aviv, Israel, 2013 Software Development Kits.

  12. Optical Fiber Distributed Sensing Structural Health Monitoring (SHM) Strain Measurements Taken During Cryotank Y-Joint Test Article Load Cycling at Liquid Helium Temperatures (United States)

    Allison, Sidney G.; Prosser, William H.; Hare, David A.; Moore, Thomas C.; Kenner, Winfred S.


    This paper outlines cryogenic Y-joint testing at Langley Research Center (LaRC) to validate the performance of optical fiber Bragg grating strain sensors for measuring strain at liquid helium temperature (-240 C). This testing also verified survivability of fiber sensors after experiencing 10 thermal cool-down, warm-up cycles and 400 limit load cycles. Graphite composite skins bonded to a honeycomb substrate in a sandwich configuration comprised the Y-joint specimens. To enable SHM of composite cryotanks for consideration to future spacecraft, a light-weight, durable monitoring technology is needed. The fiber optic distributed Bragg grating strain sensing system developed at LaRC is a viable substitute for conventional strain gauges which are not practical for SHM. This distributed sensing technology uses an Optical Frequency Domain Reflectometer (OFDR). This measurement approach has the advantage that it can measure hundreds of Bragg grating sensors per fiber and the sensors are all written at one frequency, greatly simplifying fiber manufacturing. Fiber optic strain measurements compared well to conventional strain gauge measurements obtained during these tests. These results demonstrated a high potential for a successful implementation of a SHM system incorporating LaRC's fiber optic sensing system on the composite cryotank and other future cryogenic applications.

  13. Optimization of Resistance Spot Weld Condition for Single Lap Joint of Hot Stamped 22MnB5 by Taking Heating Temperature and Heating Time into Consideration

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hong Seok; Kim, Byung Min; Park, Geun Hwan [Pusan National University, Busan (Korea, Republic of); Lim, Woo Seung [Keimyung University, Daegu (Korea, Republic of)


    In this study, optimization of the process parameters of the resistance spot welding of a sheet of aluminum-coated boron alloyed steel, 22MnB5, used in hot stamping has been performed by a Taguchi method to increase the strength of the weld joint. The process parameters selected were current, electrode force, and weld time. The heating temperature and heating time of 22MnB5 are considered to be noise factors. It was known that the variation in the thickness of the intermetallic compound layer between the aluminum-coated layer and the substrate, which influences on the formation of nugget, was generated due to the difference of diffusion reaction according to heating conditions. From the results of spot weld experiment, the optimum weld condition was determined to be when the current, electrode force, and weld time were 8kA, 4kN, and 18 cycles, respectively. The result of a test performed to verify the optimized weld condition showed that the tensile strength of the weld joint was over 32kN, which is considerably higher than the required strength, i.e., 23kN.

  14. Strength analysis of adhesive joints of riser pipes in deep sea environment loadings

    National Research Council Canada - National Science Library

    Zhang, Yu; Qin, Tai Yan; Noda, Nao Aki; Duan, Meng Lan


    Nowadays, adhesive joints are widely used in riser pipes, which are subjected to many kinds of loadings in deep sea, such as external pressure, internal pressure, tension, torsion, bending, and also...

  15. Mechanical analysis of the malformed, yet functional, mandibular joints of a wild timber wolf, Canis lupus. (United States)

    Barrette, C


    In spite of grossly malformed jaw joints, presumably from birth, the animal survived in the wild for at least 3 years. Instead of a deep glenoid fossa folded over a cylindrical condyle to form a hinge, both joints had freely open articulating surfaces and a mandibular condyle without neck. The neckless condyle produced a shorter moment arm of resistance in all biting positions. The moment arm of the masseter, the jaw-adductor tending to disarticulate the jaw, was longer as a result of an elongated angular process. The combined effect at the carnassials was a 36 per cent improvement in the efficiency of the lever for which the joint is the fulcrum and thus an equivalent reduction in the disarticulating force. The joints were held together by an extra stout ligament about 5 mm in diameter and 8 mm long, linking the lateral pole of the condyle to the zygomatic arch.

  16. Analysis of Cooperative Education as a Work/Education Joint Venture. (United States)

    Wilson, James W.


    Examines why joint ventures are formed and discusses a number of factors related to the success of such interaction. Focus is on four factors: goal compatibility, boundary-spanning structures and processes, locus of need satisfaction, and organizational incentives. (CT)


    The open-source, public domain JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) API (Application Programming Interface) provides conventions and Fortran-90 modules to develop applications (computer programs) for analyzing process models. The input ...

  18. Analysis of Low-Temperature Utilization of Geothermal Resources

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Brian


    Full realization of the potential of what might be considered “low-grade” geothermal resources will require that we examine many more uses for the heat than traditional electricity generation. To demonstrate that geothermal energy truly has the potential to be a national energy source we will be designing, assessing, and evaluating innovative uses for geothermal-produced water such as hybrid biomass-geothermal cogeneration of electricity and district heating and efficiency improvements to the use of cellulosic biomass in addition to utilization of geothermal in district heating for community redevelopment projects. The objectives of this project were: 1) to perform a techno-economic analysis of the integration and utilization potential of low-temperature geothermal sources. Innovative uses of low-enthalpy geothermal water were designed and examined for their ability to offset fossil fuels and decrease CO2 emissions. 2) To perform process optimizations and economic analyses of processes that can utilize low-temperature geothermal fluids. These processes included electricity generation using biomass and district heating systems. 3) To scale up and generalize the results of three case study locations to develop a regionalized model of the utilization of low-temperature geothermal resources. A national-level, GIS-based, low-temperature geothermal resource supply model was developed and used to develop a series of national supply curves. We performed an in-depth analysis of the low-temperature geothermal resources that dominate the eastern half of the United States. The final products of this study include 17 publications, an updated version of the cost estimation software GEOPHIRES, and direct-use supply curves for low-temperature utilization of geothermal resources. The supply curves for direct use geothermal include utilization from known hydrothermal, undiscovered hydrothermal, and near-hydrothermal EGS resources and presented these results at the Stanford

  19. Numerical Evaluation of Temperature Field and Residual Stresses in an API 5L X80 Steel Welded Joint Using the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Jailson A. Da Nóbrega


    Full Text Available Metallic materials undergo many metallurgical changes when subjected to welding thermal cycles, and these changes have a considerable influence on the thermo-mechanical properties of welded structures. One method for evaluating the welding thermal cycle variables, while still in the project phase, would be simulation using computational methods. This paper presents an evaluation of the temperature field and residual stresses in a multipass weld of API 5L X80 steel, which is extensively used in oil and gas industry, using the Finite Element Method (FEM. In the simulation, the following complex phenomena were considered: the variation in physical and mechanical properties of the material as a function of the temperature, welding speed and convection and radiation mechanisms. Additionally, in order to characterize a multipass weld using the Gas Tungsten Arc Welding process for the root pass and the Shielded Metal Arc Welding process for the filling passes, the analytical heat source proposed by Goldak and Chakravarti was used. In addition, we were able to analyze the influence of the mesh refinement in the simulation results. The findings indicated a significant variation of about 50% in the peak temperature values. Furthermore, changes were observed in terms of the level and profile of the welded joint residual stresses when more than one welding pass was considered.

  20. Improving Soil Moisture Estimation with a Dual Ensemble Kalman Smoother by Jointly Assimilating AMSR-E Brightness Temperature and MODIS LST

    Directory of Open Access Journals (Sweden)

    Weijing Chen


    Full Text Available Uncertainties in model parameters can easily result in systematic differences between model states and observations, which significantly affect the accuracy of soil moisture estimation in data assimilation systems. In this research, a soil moisture assimilation scheme is developed to jointly assimilate AMSR-E (Advanced Microwave Scanning Radiometer-Earth Observing System brightness temperature (TB and MODIS (Moderate Resolution Imaging Spectroradiometer Land Surface Temperature (LST products, which also corrects model bias by simultaneously updating model states and parameters with a dual ensemble Kalman filter (DEnKS. Common Land Model (CoLM and a Radiative Transfer Model (RTM are adopted as model and observation operator, respectively. The assimilation experiment was conducted in Naqu on the Tibet Plateau from 31 May to 27 September 2011. The updated soil temperature at surface obtained by assimilating MODIS LST serving as inputs of RTM is to reduce the differences between the simulated and observed TB, then AMSR-E TB is assimilated to update soil moisture and model parameters. Compared with in situ measurements, the accuracy of soil moisture estimation derived from the assimilation experiment has been tremendously improved at a variety of scales. The updated parameters effectively reduce the states bias of CoLM. The results demonstrate the potential of assimilating AMSR-E TB and MODIS LST to improve the estimation of soil moisture and related parameters. Furthermore, this study indicates that the developed scheme is an effective way to retrieve downscaled soil moisture when assimilating the coarse-scale microwave TB.

  1. The analysis of implementation options of transverse joints of bitumen sheets

    Directory of Open Access Journals (Sweden)

    Plachý Jan


    Full Text Available One of the most frequent sources of faults on flat roofs is a violation of the waterproof layers along the transverse joints between bitumen sheets. This fault is caused by a failure to adhere to the technological methodologies. This paper presents current solutions, as well as a new solution, for creating such joints. The new solutions are experimentally compared with existing solutions.

  2. The Fuzzy Finite Element Stress Analysis of Adhesive-Bonded Single Lap Joints


    Alpay AYDEMİR


    An adhesive-bonded single lap joint is analyzed using a new fuzzy finite element model. In the model, Young's moduli and Poisson's ratios of the joint materials are taken as fuzzy numbers in order to take the uncertainty of the material properties into account. The fuzzy numbers are modeled using linear triangular membership functions. At a selected material point in the adhesive layer, the possibility distributions for the displacements and shear stresses are depi...

  3. Case Analysis Of The Joint High Speed Vessel Program: Defense Acquisition (United States)


    Strategy that renewed the focus of combat operations on smaller, projectable, and dynamic joint fight entities, both the Army and Navy reviewed requirements...combat operations on smaller, projectable, and dynamic joint fight entities, both the Army and Navy reviewed requirements to address capability...were a paramount concern and weighed heavily in the development of Army requirements that originated in the Operational Requirements Document (ORD

  4. The effect of temperature on the SCC behavior of AISI301L stainless steel welded joints in 3.5% NaCl solution (United States)

    Fu, Z. H.; Gou, G. Q.; Xiao, J.; Qiu, S. Y.; Wang, W. J.


    The stress corrosion cracking (SCC) behaviors at slow strain rate tensile (SSRT) test of AISI301L stainless steel laser-MIG welded joints in 3.5 wt.% NaCl solution at 20∘C, 40∘C and 60∘C were investigated. The results showed that the weld metal composed of as-cast with δ-Fe and austenite. The base metal (BM) and heat affected zone (HAZ) contained strain-induced M phase. The stress and strain decreased with the increasing temperature. The SCC cracks are initiated by anodic dissolution at 20∘C. Besides the anodic dissolution mechanism, hydrogen-induced SCC mechanism had appeared in 3.5 wt.% NaCl solution at 40∘C and 60∘C.

  5. Joint probability analysis of extreme precipitation and storm tide in a coastal city under changing environment. (United States)

    Xu, Kui; Ma, Chao; Lian, Jijian; Bin, Lingling


    Catastrophic flooding resulting from extreme meteorological events has occurred more frequently and drawn great attention in recent years in China. In coastal areas, extreme precipitation and storm tide are both inducing factors of flooding and therefore their joint probability would be critical to determine the flooding risk. The impact of storm tide or changing environment on flooding is ignored or underestimated in the design of drainage systems of today in coastal areas in China. This paper investigates the joint probability of extreme precipitation and storm tide and its change using copula-based models in Fuzhou City. The change point at the year of 1984 detected by Mann-Kendall and Pettitt's tests divides the extreme precipitation series into two subsequences. For each subsequence the probability of the joint behavior of extreme precipitation and storm tide is estimated by the optimal copula. Results show that the joint probability has increased by more than 300% on average after 1984 (α = 0.05). The design joint return period (RP) of extreme precipitation and storm tide is estimated to propose a design standard for future flooding preparedness. For a combination of extreme precipitation and storm tide, the design joint RP has become smaller than before. It implies that flooding would happen more often after 1984, which corresponds with the observation. The study would facilitate understanding the change of flood risk and proposing the adaption measures for coastal areas under a changing environment.

  6. Screw-Home Movement of the Tibiofemoral Joint during Normal Gait: Three-Dimensional Analysis. (United States)

    Kim, Ha Yong; Kim, Kap Jung; Yang, Dae Suk; Jeung, Sang Wook; Choi, Han Gyeol; Choy, Won Sik


    The purpose of this study was to evaluate the screw-home movement at the tibiofemoral joint during normal gait by utilizing the 3-dimensional motion capture technique. Fifteen young males and fifteen young females (total 60 knee joints) who had no history of musculoskeletal disease or a particular gait problem were included in this study. Two more markers were attached to the subject in addition to the Helen-Hayes marker set. Thus, two virtual planes, femoral coronal plane (P f ) and tibial coronal plane (P t ), were created by Skeletal Builder software. This study measured the 3-dimensional knee joint movement in the sagittal, coronal, and transverse planes of these two virtual planes (P f and P t ) during normal gait. With respect to kinematics and kinetics, both males and females showed normal adult gait patterns, and the mean difference in the temporal gait parameters was not statistically significant (p > 0.05). In the transverse plane, the screw-home movement occurred as expected during the pre-swing phase and the late-swing phase at an angle of about 17°. However, the tibia rotated externally with respect to the femur, rather than internally, while the knee joint started to flex during the loading response (paradoxical screw-home movement), and the angle was 6°. Paradoxical screw-home movement may be an important mechanism that provides stability to the knee joint during the remaining stance phase. Obtaining the kinematic values of the knee joint during gait can be useful in diagnosing and treating the pathological knee joints.

  7. Comparison of two methodological approaches for the mechanical analysis of single-joint isoinertial movement using a customised isokinetic dynamometer(). (United States)

    Plautard, Mathieu; Guilhem, Gaël; Fohanno, Vincent; Nordez, Antoine; Cornu, Christophe; Guével, Arnaud


    Compared to isokinetic and isometric tests, isoinertial movements have been poorly used to assess single-joint performance. Two calculation procedures were developed to estimate mechanical performance during single-joint isoinertial movements performed on a customised isokinetic dynamometer. The results were also compared to appreciate the effects of measurement systems and calculation procedures. Five participants performed maximal knee extensions at four levels of resistance (30, 50, 70 and 90% of the one-repetition maximum, 1-RM). Joint angular velocity and torque were assessed from customised isokinetic dynamometer measures (method A) and from weight stack kinematic (method B). Bland-Altman plots and mean percent differences (Mdiff) were used to assess the level of agreement for mean and peak angular velocity and torque. A Passing-Bablok regression was performed to compare the angular velocity-angle and torque-angle relationships computed from the two analysis methods. The results showed a high level of agreement for all mechanical parameters (Mdiff < 6% for all parameters). No statistically significant differences were observed between methods A and B in terms of angular velocity-angle and torque-angle relationships except at 30% of 1-RM for the torque-angle relationship. Both methodologies provide comparable values of angular velocity and torque, offering alternative approaches to assess neuromuscular function from single-joint isoinertial movements.

  8. Experimental Investigation and Finite Element Analysis on Fatigue Behavior of Aluminum Alloy 7050 Single-Lap Joints (United States)

    Zhou, Bing; Cui, Hao; Liu, Haibo; Li, Yang; Liu, Gaofeng; Li, Shujun; Zhang, Shangzhou


    The fatigue behavior of single-lap four-riveted aluminum alloy 7050 joints was investigated by using high-frequency fatigue test and scanning electron microscope (SEM). Stress distributions obtained by finite element (FE) analysis help explain the fatigue performance. The fatigue test results showed that the fatigue lives of the joints depend on cold expansion and applied cyclic loads. FE analysis and fractography indicated that the improved fatigue lives can be attributed to the reduction in maximum stress and evolution of fatigue damage at the critical location. The beneficial effects of strengthening techniques result in tearing ridges or lamellar structure on fracture surface, decrease in fatigue striations spacing, delay of fatigue crack initiation, crack deflection in fatigue crack propagation and plasticity-induced crack closure.

  9. Diagnosis of periprosthetic joint infection in Medicare patients: multicriteria decision analysis. (United States)

    Diaz-Ledezma, Claudio; Lichstein, Paul M; Dolan, James G; Parvizi, Javad


    In the setting of finite healthcare resources, developing cost-efficient strategies for periprosthetic joint infection (PJI) diagnosis is paramount. The current levels of knowledge allow for PJI diagnostic recommendations based on scientific evidence but do not consider the benefits, opportunities, costs, and risks of the different diagnostic alternatives. We determined the best diagnostic strategy for knee and hip PJI in the ambulatory setting for Medicare patients, utilizing benefits, opportunities, costs, and risks evaluation through multicriteria decision analysis (MCDA). The PJI diagnostic definition supported by the Musculoskeletal Infection Society was employed for the MCDA. Using a preclinical model, we evaluated three diagnostic strategies that can be conducted in a Medicare patient seen in the outpatient clinical setting complaining of a painful TKA or THA. Strategies were (1) screening with serum markers (erythrocyte sedimentation rate [ESR]/C-reactive protein [CRP]) followed by arthrocentesis in positive cases, (2) immediate arthrocentesis, and (3) serum markers requested simultaneously with arthrocentesis. MCDA was conducted through the analytic hierarchy process, comparing the diagnostic strategies in terms of benefits, opportunities, costs, and risks. Strategy 1 was the best alternative to diagnose knee PJI among Medicare patients (normalized value: 0.490), followed by Strategy 3 (normalized value: 0.403) and then Strategy 2 (normalized value: 0.106). The same ranking of alternatives was observed for the hip PJI model (normalized value: 0.487, 0.405, and 0.107, respectively). The sensitivity analysis found this sequence to be robust with respect to benefits, opportunities, and risks. However, if during the decision-making process, cost savings was given a priority of higher than 54%, the ranking for the preferred diagnostic strategy changed. After considering the benefits, opportunities, costs, and risks of the different available alternatives, our

  10. Solar Alpha Rotary Joint (SARJ) Lubrication Interval Test and Evaluation (LITE). Post-Test Grease Analysis (United States)

    Golden, Johnny L.; Martinez, James E.; Devivar, Rodrigo V.


    The Solar Alpha Rotary Joint (SARJ) is a mechanism of the International Space Station (ISS) that orients the solar power generating arrays toward the sun as the ISS orbits our planet. The orientation with the sun must be maintained to fully charge the ISS batteries and maintain all the other ISS electrical systems operating properly. In 2007, just a few months after full deployment, the starboard SARJ developed anomalies that warranted a full investigation including ISS Extravehicular Activity (EVA). The EVA uncovered unexpected debris that was due to degradation of a nitride layer on the SARJ bearing race. ISS personnel identified the failure root-cause and applied an aerospace grease to lubricate the area associated with the anomaly. The corrective action allowed the starboard SARJ to continue operating within the specified engineering parameters. The SARJ LITE (Lubrication Interval Test and Evaluation) program was initiated by NASA, Lockheed Martin, and Boeing to simulate the operation of the ISS SARJ for an extended time. The hardware was designed to test and evaluate the exact material components used aboard the ISS SARJ, but in a controlled area where engineers could continuously monitor the performance. After running the SARJ LITE test for an equivalent of 36+ years of continuous use, the test was opened to evaluate the metallography and lubrication. We have sampled the SARJ LITE rollers and plate to fully assess the grease used for lubrication. Chemical and thermal analysis of these samples has generated information that has allowed us to assess the location, migration, and current condition of the grease. The collective information will be key toward understanding and circumventing any performance deviations involving the ISS SARJ in the years to come.

  11. Prediction model of a joint analysis of beef growth and carcass quality traits. (United States)

    Mirzaei, H R; Verbyla, A P; Pitchford, W S


    A joint growth-carcass analysis was conducted to develop equations for predicting carcass quality traits associated with variation in growth path of crossbred cattle. During a four-year period (1994-1997) of the Australian "Southern Crossbreeding Project", mature Hereford cows (r = 581) were mated to 97 sires of Jersey, Wagyu, Angus, Hereford, South Devon, Limousin, and Belgian Blue breeds, resulting in 1141 calves. Data included body weight measurements of steers and heifers from birth until slaughter and four carcass quality traits: hot standard carcass weight, rump fat depth, rib eye muscle area, and intramuscular fat content. The model provides nine outputs: median and mean of carcass quality traits, predicted means, and lower and upper confidence intervals, as well as predicted intervals of carcass quality traits (95%) and economic values for domestic market and export markets. Input to the model consists of sex, sire breeds, age (in days)-weight (kg) pairs and slaughter age (500 days for heifer and 700 days for steers). The prediction model is able to accommodate different sexes across seven sire breeds and various management groups at any slaughter age. Its strength lies in its simplicity and flexibility, desirable to accommodate producers with different management schemes. In general, fat depth and intramuscular fat were found to be more affected by differences in growth rate than hot carcass weight and eye muscle area. Also, export market value was more sensitive to growth rate modifications than domestic market value. This model provides a tool by which the producer can estimate the impact of management decisions.

  12. Effect of Temperature and Viscoelastic Creep on the Clamp-Up Load in Hybrid Composite/Metal Bolted Joints (United States)


    2.22 shows the Mathcad sheet used to demonstrate this specific example. The result shows that the load in a single bolt, hybrid aluminum to EGlass...34 8tbK \\ ’ ’ P, = 5>«2 lbs/F KAI + Kc + Kb Figure 2.22 - Mathcad Calculation Example Print Out 59 Connection Load Response as a...Correction Factor Computation Figure C.l displays a screen shot of the Mathcad sheet used to compute the temperature correction factor, Kpt or TFact in

  13. The Power-Load Relationship During a Countermovement Jump: A Joint Level Analysis. (United States)

    Williams, Kym J; Chapman, Dale W; Phillips, Elissa J; Ball, Nick


    This study aimed to investigate if hip, knee and ankle peak power is influenced by the relative load lifted, altering the joint and system load-power relationship during a countermovement jump (CMJ). Twenty-Three male national representative athletes (age: 20.3 ± 3.1y, squat 1RM: 133.8 ± 24.8kg) completed three CMJs at relative barbell loads of 0, 10, 20, 30 and 40% of an athlete's estimated back squat 1RM. Ground reaction force and joint kinematics were captured using a 16 camera motion capture array integrated with two in ground tri-axial force plates. Hip (x~ = 20%, range 0 > 40%), knee (x~ = 0%, 0 > 20%) and ankle (x~ = 40%, 0 > 40%) peak power was maximized at different percentages of absolute strength, with an athlete dependent variation in load-power profiles observed across all lower-body joints. A decrease in system (body + barbell mass) peak power was significantly (Pload increased. The findings highlight that the generation and translation of lower-body joint power is influenced by external load and athlete-dependent traits. This subsequently alters the power-load profile at a system level, explaining the broad spectrums of loads reported to optimize system power during a CMJ. When training, we recommend that a combination of barbell loads based on assorted percentages of the estimated 1RM be prescribed to optimize joint and system power during a CMJ.

  14. Quantitative investigation of ligament strains during physical tests for sacroiliac joint pain using finite element analysis. (United States)

    Kim, Yoon Hyuk; Yao, Zhidong; Kim, Kyungsoo; Park, Won Man


    It may be assumed that the stability is affected when some ligaments are injured or loosened, and this joint instability causes sacroiliac joint pain. Several physical examinations have been used to diagnose sacroiliac pain and to isolate the source of the pain. However, more quantitative and objective information may be necessary to identify unstable or injured ligaments during these tests due to the lack of understanding of the quantitative relationship between the physical tests and the biomechanical parameters that may be related to pains in the sacroiliac joint and the surrounding ligaments. In this study, a three-dimensional finite element model of the sacroiliac joint was developed and the biomechanical conditions for six typical physical tests such as the compression test, distraction test, sacral apex pressure test, thigh thrust test, Patrick's test, and Gaenslen's test were modelled. The sacroiliac joint contact pressure and ligament strain were investigated for each test. The values of contact pressure and the combination of most highly strained ligaments differed markedly among the tests. Therefore, these findings in combination with the physical tests would be helpful to identify the pain source and to understand the pain mechanism. Moreover, the technology provided in this study might be a useful tool to evaluate the physical tests, to improve the present test protocols, or to develop a new physical test protocol. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Experimental analysis of dissimilar metal weld joint: Ferritic to austenitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Rathod, Dinesh W., E-mail: [Department of Mechanical Engineering, Indian Institute of Technology Delhi, New Delhi 110016 (India); Pandey, Sunil [Department of Mechanical Engineering, Indian Institute of Technology Delhi, New Delhi 110016 (India); Singh, P.K. [Bhabha Atomic Research Centre, Mumbai 400085 (India); Prasad, Rajesh [Department of Applied Mechanics, Indian Institute of Technology Delhi, New Delhi 110016 (India)


    The dissimilar metal weld (DMW) joint between SA508Gr.3Cl.1 ferritic steel and SS304LN using Inconel 82/182 consumables was required in the nuclear power plants. The joint integrity assessment of these welds requires mechanical and metallurgical properties evaluation in weldment regions. The joint was subjected to 100% radiography test and bend test and transverse tensile test. Welding and testing were carried out as per the requirements of ASME Sec-IX and acceptance criteria as per ASME Sec-III. The transverse tensile test results indicated the failure from the weld metal although it satisfies the minimum strength requirement of the ASME requirements; therefore, the DMW joint was analyzed in detail. Straight bead deposition technique, fine slag inclusion, less reliable radiograph technique, plastic instability stress, yield strength ratio and metallurgical deteriorations have been contributed to failure of the DMW joint from the weld region. In the present work, the factors contributing to the fracture from weld metal have been discussed and analyzed.

  16. Loads in the hip joint during physically demanding occupational tasks: A motion analysis study. (United States)

    Varady, Patrick Aljoscha; Glitsch, Ulrich; Augat, Peter


    Epidemiologic studies of osteoarthritis of the hip indicate a possible connection between work related activities and the pathogenesis of the disease. This study investigated the hip joint contact forces for physically demanding occupational tasks (lifting, carrying, transferring of a weight (mass: 25 kg, 40 kg and 50 kg); stair climbing without and with additional load of 25 kg; ladder climbing) and compared these with everyday activities (level gait, sitting down and getting up). The hip joint contact force was calculated with the human multibody simulation software AnyBody employing motion capture and ground reaction force measurements by force plates and an instrumented staircase and ladder. Although the results for 11 male test subjects showed individual variations, a general trend could be observed in regards of force curves' characteristics and maxima. The largest joint contact forces calculated were (637 ± 148)%-body weight for horizontal transfer of a 50 kg weight. For several of the occupational activities the computed hip joint contact forces were significantly larger compared to the investigated examples of activities of daily living. This study provides original data of simulated hip joint contact forces for physically demanding activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Performance Analysis of a Self-Propelling Flat Plate Fin with Joint Compliance (United States)

    Reddy, N. Srinivasa; Sen, Soumen; Pal, Sumit; Shome, Sankar Nath


    Fish fin muscles are compliant and they regulate the stiffness to suit different swimming conditions. This article attempts to understand the significance of presence of compliance in fin muscle with help of a flexible joint flat plate fin model. Blade element method is employed to model hydrodynamics and to compute the forces of interaction during motion of the plate within fluid. The dynamic model of self-propelling fin is developed through multi-body dynamics approach considering the hydrodynamic forces as external forces acting on the fin. The derived hydrodynamic model is validated with experiments on rigid flat plate fin. The effect of the joint stiffness and flapping frequency on the propulsion speed and efficiency is investigated through simulations using the derived and validated model. The propulsion efficiency is found to be highly influenced by the joint stiffness at a given flapping frequency. The fin attained maximum propulsion efficiency when the joint stiffness is tuned to a value at which flapping frequency matches near natural frequency of the fin. At this tuned joint stiffness and flapping frequency, the resulted Strouhal numbers are observed to fall within the optimum range (0.2 to 0.4) for maximized propulsion efficiency of flying birds and swimming aquatic animals reported in literature.

  18. Analysis on the Fracture of Al-Cu Dissimilar Materials Friction Stir Welding Lap Joint (United States)

    Sun, Hongyu; Zhou, Qi; Zhu, Jun; Peng, Yong


    Friction stir welding (FWS) is regarded as a more plausible alternative to other welding methods for Al-Cu dissimilar joining. However, the structure of an FSW joint is different from others. In this study, lap joints of 6061 aluminum alloy and commercially pure copper were produced by FSW, and the effects of rotation rate on macromorphology, microstructure and mechanical properties were investigated. In addition, a fracture J integral model was used to analyze the effect of microstructure on the mechanical properties. The results revealed that the macrodefect-free joints were obtained at a feed rate of 150 mm/min and 1100 rpm and that the failure load of the joint reached as high as 4.57 kN and only reached 2.91 kN for the 900 rpm, where tunnel defects were identified. Particle-rich zones composed of Cu particles dispersed in an Al matrix, and "Flow tracks" were observed by the EDS. The J integral results showed that the microdefects on the advancing side cause serious stress concentration compared with the microdefects located on the Al-Cu interface, resulting in the fracture of the joints.

  19. Analysis on the Fracture of Al-Cu Dissimilar Materials Friction Stir Welding Lap Joint (United States)

    Sun, Hongyu; Zhou, Qi; Zhu, Jun; Peng, Yong


    Friction stir welding (FWS) is regarded as a more plausible alternative to other welding methods for Al-Cu dissimilar joining. However, the structure of an FSW joint is different from others. In this study, lap joints of 6061 aluminum alloy and commercially pure copper were produced by FSW, and the effects of rotation rate on macromorphology, microstructure and mechanical properties were investigated. In addition, a fracture J integral model was used to analyze the effect of microstructure on the mechanical properties. The results revealed that the macrodefect-free joints were obtained at a feed rate of 150 mm/min and 1100 rpm and that the failure load of the joint reached as high as 4.57 kN and only reached 2.91 kN for the 900 rpm, where tunnel defects were identified. Particle-rich zones composed of Cu particles dispersed in an Al matrix, and "Flow tracks" were observed by the EDS. The J integral results showed that the microdefects on the advancing side cause serious stress concentration compared with the microdefects located on the Al-Cu interface, resulting in the fracture of the joints.

  20. A sensitivity analysis method for the body segment inertial parameters based on ground reaction and joint moment regressor matrices. (United States)

    Futamure, Sumire; Bonnet, Vincent; Dumas, Raphael; Venture, Gentiane


    This paper presents a method allowing a simple and efficient sensitivity analysis of dynamics parameters of complex whole-body human model. The proposed method is based on the ground reaction and joint moment regressor matrices, developed initially in robotics system identification theory, and involved in the equations of motion of the human body. The regressor matrices are linear relatively to the segment inertial parameters allowing us to use simple sensitivity analysis methods. The sensitivity analysis method was applied over gait dynamics and kinematics data of nine subjects and with a 15 segments 3D model of the locomotor apparatus. According to the proposed sensitivity indices, 76 segments inertial parameters out the 150 of the mechanical model were considered as not influent for gait. The main findings were that the segment masses were influent and that, at the exception of the trunk, moment of inertia were not influent for the computation of the ground reaction forces and moments and the joint moments. The same method also shows numerically that at least 90% of the lower-limb joint moments during the stance phase can be estimated only from a force-plate and kinematics data without knowing any of the segment inertial parameters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Analysis of an adhesively bonded single lap joint subjected to eccentric loading

    DEFF Research Database (Denmark)

    Anyfantis, Konstantinos; Tsouvalis, N. G.


    is benchmarking of computational tools. The test is based on a Single Lap Joint subjected to Eccentric Loading (SLJ-EL). The basic concept that lies behind this configuration is that the applied in-plane tensile load leads the adhesive layer to develop normal stresses, in-plane and out-of-plane shear stresses......A new experimental test is proposed, which allows the contribution of Mode I, II and III fracture modes to the failure of the adhesive layer of bonded joints aiming at achieving the realistic conditions often occurring during loading of practical joints. The main objective of this test......, which correspond to Mode I, II and III loading and fracture. These tests were designed so that the metal substrates do not enter plasticity and the adhesive achieves a mode mixity ratio between Mode II and Mode III not lower than 0.5. The experiments were simulated in a 3-dimensional finite element...

  2. Total arthroplasty of basal thumb joint with Elektra prothesis: an in vitro analysis. (United States)

    Completo, A; Nascimento, A; Neto, F


    The reported outcomes of the Elektra thumb carpo-metacarpal joint implant have been very variable. This study evaluates the influence of daily cyclic loads and the type of the screw-fit cup insertion technique in the trapezium, with and without prior threading, on the structural bone behaviour. The study was performed experimentally to predict initial implant stability and cortical bone strains. Computational models were developed to assess the structural cancellous bone behaviour. The use of Elektra implant considerably changed the bone strain behaviour compared with the intact joint. This may be associated with risks of cancellous bone fatigue failure due to overload, particularly in the trapezium. The joint load magnitude has a more important structural role than that of the screw-fit cup insertion technique. Limiting the magnitude of thumb loads after arthroplasty may contribute positively to the longevity of this procedure. V.

  3. Analysis of pain in the rabbit temporomandibular joint after unilateral splint placement. (United States)

    Henderson, Sarah E; Tudares, Mauro A; Gold, Michael S; Almarza, Alejandro J


    To determine whether behavioral, anatomical, and physiologic endpoints widely used to infer the presence of pain in rodent models of temporomandibular disorders (TMD) were applicable to the rabbit model of TMD associated with altered joint loading. Unilateral molar dental splints were used to alter temporomandibular joint (TMJ) loading. Changes in nociceptive threshold were assessed with a mechanical probing of the TMJ region on nine splinted and three control rabbits. Fos-like immunoreacitivty in the trigeminal subnucleus caudalis was assessed with standard immunohistochemical techniques from three splinted and six control animals. Retrogradely labeled TMJ afferents were studied with patch-clamp electrophysiologic techniques from three splinted and three control animals. Remodeling of TMJ condyles was assessed by histologic investigations of three splinted and three control animals. A Student t test or a Mann-Whitney U test was used with significance set at P joint degeneration. These compensatory changes may reflect pain-adaption processes that many patients with TMJ disorders experience.

  4. Stiffness Analysis of Nail-Plate Joints Subjected to Short-Term Loads

    DEFF Research Database (Denmark)

    Nielsen, Jacob

    with beams connected in joints with glue or a mechanical fastener. The types of mechanical fasteners are: nails, staples, bolts, dowels, screws and nail-plates. Bolts and dowels are generally applied to joints in solid structures, and the other fasteners are used in all kinds of light structures. Especially...... nail-plates are designed for trusses. For many years, joints were made of boards with nails, but the increasing industrialism and the need for quick and usable assembly had the result that today nearly all trusses are pre-fabricated with nail-plates. The word "nail-plate" has been used for different...... types of plates. There are two main types of nail-plates: steel plates perforated with holes in which separate nails are used and steel plates perforated by a stamping machine, so the nails are made from the plate, see figur 1.2 on page 7. This type is sometimes called "punching metal plate...

  5. Kinematics based physical modelling and experimental analysis of the shoulder joint complex

    Directory of Open Access Journals (Sweden)

    Diego Almeida-Galárraga


    Full Text Available The purpose of this work is to develop an experimental physical model of the shoulder joint complex. The aim of this research is to validate the model built and identify the forces on specified positions of this joint. The shoulder musculoskeletal structures have been replicated to evaluate the forces to which muscle fibres are subjected in different equilibrium positions: 60º flexion, 60º abduction and 30º abduction and flexion. The physical model represents, quite accurately, the shoulder complex. It has 12 real degrees of freedom, which allows motions such as abduction, flexion, adduction and extension and to calculate the resultant forces of the represented muscles. The built physical model is versatile and easily manipulated and represents, above all, a model for teaching applications on anatomy and shoulder joint complex biomechanics. Moreover, it is a valid research tool on muscle actions related to abduction, adduction, flexion, extension, internal and external rotation motions or combination among them.

  6. Non-destructive Residual Stress Analysis Around The Weld-Joint of Fuel Cladding Materials of ZrNbMoGe Alloys

    Directory of Open Access Journals (Sweden)



    Full Text Available The residual stress measurements around weld-joint of ZrNbMoGe alloy have been carried out by using X-ray diffraction technique in PTBIN-BATAN. The research was performed to investigate the structure of a cladding material with high temperature corrosion resistance and good weldability. The equivalent composition of the specimens (in %wt. was 97.5%Zr1%Nb1%Mo½%Ge. Welding was carried out by using TIG (tungsten inert gas technique that completed butt-joint with a current 20 amperes. Three region tests were taken in specimen while diffraction scanning, While diffraction scanning, tests were performed on three regions, i.e., the weldcore, the heat-affected zone (HAZ and the base metal. The reference region was determined at the base metal to be compared with other regions of the specimen, in obtaining refinement structure parameters. Base metal, HAZ and weldcore were diffracted by X-ray, and lattice strain changes were calculated by using Rietveld analysis program. The results show that while the quantity of minor phases tend to increase in the direction from the base metal to the HAZ and to the weldcore, the quantity of the ZrGe phase in the HAZ is less than the quantity of the ZrMo2 phase due to tGe element evaporation. The residual stress behavior in the material shows that minor phases, i.e., Zr3Ge and ZrMo2, are more dominant than the Zr matrix. The Zr3Ge and ZrMo2 experienced sharp straining, while the Zr phase was weak-lined from HAZ to weldcore. The hydrostatic residual stress ( in around weld-joint of ZrNbMoGe alloy is compressive stress which has minimum value at about -2.73 GPa in weldcore region

  7. Effect of an anterior-sloped brace joint on anterior tibial translation and axial tibial rotation: a motion analysis study. (United States)

    Yeow, C H; Gan, W L; Lee, P V S; Goh, J C H


    Anterior tibial translation and axial tibial rotation are major biomechanical factors involved in anterior cruciate ligament injuries. This study sought to evaluate a brace prototype designed with an anterior-sloped joint, in terms of its efficacy in attenuating anterior tibial translation and axial tibial rotation during landing, using a motion analysis approach. Ten healthy male subjects performed single-leg landing tasks from a 0.6-m height with and without the brace prototype. Ground reaction force and kinematics data were obtained using a motion-capture system and force-plates. Anterior tibial translation and axial tibial rotation were determined based on tibial and femoral marker reference frames. Vertical and anterior-posterior ground reaction forces, hip, knee and ankle joint range-of-motions and angular velocities, anterior tibial translation and axial tibial rotation were compared between unbraced and braced conditions using Wilcoxon signed-rank test. We found no significant difference in peak vertical and anterior-posterior ground reaction forces (p=0.770 and p=0.332 respectively) between unbraced and braced conditions. Knee joint range-of-motion and angular velocity were lower (p=0.037 and p=0.038 respectively) for braced condition than unbraced condition. Anterior tibial translation and axial tibial rotation were reduced (p=0.027 and p=0.006 respectively) in braced condition, compared to unbraced condition. The anterior-sloped brace joint helps to attenuate anterior tibial translation and axial tibial rotation present in the knee joint during landing. It is necessary to test the brace prototype in a sporting population with realistic sports landing situations in order to assess its effectiveness in lowering anterior cruciate ligament injury risk. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Advanced High Temperature Reactor Systems and Economic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, David Eugene [ORNL; Peretz, Fred J [ORNL; Qualls, A L [ORNL


    The Advanced High Temperature Reactor (AHTR) is a design concept for a large-output [3400 MW(t)] fluoride-salt-cooled high-temperature reactor (FHR). FHRs, by definition, feature low-pressure liquid fluoride salt cooling, coated-particle fuel, a high-temperature power cycle, and fully passive decay heat rejection. The AHTR's large thermal output enables direct comparison of its performance and requirements with other high output reactor concepts. As high-temperature plants, FHRs can support either high-efficiency electricity generation or industrial process heat production. The AHTR analysis presented in this report is limited to the electricity generation mission. FHRs, in principle, have the potential to be low-cost electricity producers while maintaining full passive safety. However, no FHR has been built, and no FHR design has reached the stage of maturity where realistic economic analysis can be performed. The system design effort described in this report represents early steps along the design path toward being able to predict the cost and performance characteristics of the AHTR as well as toward being able to identify the technology developments necessary to build an FHR power plant. While FHRs represent a distinct reactor class, they inherit desirable attributes from other thermal power plants whose characteristics can be studied to provide general guidance on plant configuration, anticipated performance, and costs. Molten salt reactors provide experience on the materials, procedures, and components necessary to use liquid fluoride salts. Liquid metal reactors provide design experience on using low-pressure liquid coolants, passive decay heat removal, and hot refueling. High temperature gas-cooled reactors provide experience with coated particle fuel and graphite components. Light water reactors (LWRs) show the potentials of transparent, high-heat capacity coolants with low chemical reactivity. Modern coal-fired power plants provide design experience

  9. Fabrication, testing and analysis of steel/composite DLS adhesive joints

    DEFF Research Database (Denmark)

    Hashim, S.; Berggreen, Christian; Tsouvalis, N.


    This paper describes experimental and numerical techniques to study the structural design of double lap shear joints that are based on thick-adherend steel/steel and steel/composite, with epoxy adhesive. A standard practical fabrication method was used to produce specimens of various dimensions...... the importance of modelling the composite layers adjacent to the adhesive bondline in order to account for the critical local stresses. The FEA results also showed that overall shear stress distributions can be used to characterise joint failure. The paper presents the experimental and numerical details with key...

  10. Modeling and analysis of novel laser weld joint designs using optical ray tracing.

    Energy Technology Data Exchange (ETDEWEB)

    Milewski, J. O. (John O.)


    Reflection of laser energy presents challenges in material processing that can lead to process inefficiency or process instability. Understanding the fundamentals of non-imaging optics and the reflective propagation of laser energy can allow process and weld joint designs to take advantage of these reflections to enhance process efficiency or mitigate detrimental effects. Optical ray tracing may be used within a 3D computer model to evaluate novel joint and fixture designs for laser welding that take advantage of the reflective propagation of laser energy. This modeling work extends that of previous studies by the author and provides comparison with experimental studies performed on highly reflective metals. Practical examples are discussed.

  11. Morphometric analysis of the temporomandibular joint with MRI in 320 joints; Morphometrische Analyse des Kiefergelenkes anhand von 320 Gelenken mit der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Lemke, A.J.; Felix, R. [Charite, Univ. Berlin, Campus Virchow-Klinikum, Klinik fuer Strahlenheilkunde (Germany); Griethe, M.; Peroz, I.; Lange, K.P. [Charite, Univ. Berlin, Campus Virchow-Klinikum, Zentrum fuer Zahnmedizin, Abt. fuer zahnaerztliche Prothetik und Alterszahnmedizin (Germany)


    Purpose: to compare several morphometric parameters in MRI with the functional status of the articular disc in a large patient group suffering from internal derangement (ID) of the temporomandibular joint (TMJ). Materials and methods: in a retrospective study, 320 analyzable high resolution MRI examinations of the TMJs obtained in a 1.5 T unit were evaluated in 184 patients with clinically suspected ID. The analysis included the anatomical structures and a number of morphometric parameters previously described in the literature. The parameters were compared with the position of the articular disc. Results: the disc position was categorized as ''normal'' (NDP, 21.9%, n = 70), ''anterior displacement with reduction on opening'' (AMR, 51.6%, n = 165) and ''anterior displacement without reduction on opening'' (AOR, 26.6%, n = 85). With increasing disc displacement, significant configurational changes of the disc were observed. Disc displacement was associated with changes of the condyle consisting of increasing deformity and other degenerative changes. A large tuberculum and marked inclination of the eminence can be seen as predisposition for the development of ID. With increasing severity of the ID, the position of the condyle moved from a centric position of the condylar center to an excentric (dorsal and cranial) position. Conclusion: MRI demonstrated that increasing disc displacement is associated with changes of the disc, condyles and condylar position in the fossa. (orig.)

  12. Efficacy of musculoskeletal manual approach in the treatment of temporomandibular joint disorder: A systematic review with meta-analysis. (United States)

    Martins, Wagner Rodrigues; Blasczyk, Juscelino Castro; Aparecida Furlan de Oliveira, Micaele; Lagôa Gonçalves, Karina Ferreira; Bonini-Rocha, Ana Clara; Dugailly, Pierre-Michel; de Oliveira, Ricardo Jacó


    Temporomandibular joint disorder (TMD) requires a complex diagnostic and therapeutic approach, which usually involves a multidisciplinary management. Among these treatments, musculoskeletal manual techniques are used to improve health and healing. To assess the effectiveness of musculoskeletal manual approach in temporomandibular joint disorder patients. A systematic review with meta-analysis. During August 2014 a systematic review of relevant databases (PubMed, The Cochrane Library, PEDro and ISI web of knowledge) was performed to identify controlled clinical trials without date restriction and restricted to the English language. Clinical outcomes were pain and range of motion focalized in temporomandibular joint. The mean difference (MD) or standard mean difference (SMD) with 95% confidence intervals (CIs) and overall effect size were calculated at every post treatment. The PEDro scale was used to demonstrate the quality of the included studies. From the 308 articles identified by the search strategy, 8 articles met the inclusion criteria. The meta-analysis showed a significant difference (p manual techniques when compared to other conservative treatments for TMD. Musculoskeletal manual approaches are effective for treating TMD. In the short term, there is a larger effect regarding the latter when compared to other conservative treatments for TMD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Interdependence, Interoperability, and Integration: Joint Force Analysis at the Operational Level (United States)


    Westpmt: Greenwood Press, 1993), 171-174. 4 Gordon N. Lederman , Reorganization of the Joint Chiefs of Staff: The Goldwater-Nichols Act of 1986...Historical Perspectives of the Operational Art, Washington, D.C.: Center of Military History, United States Army, 2005 Lederman , Gordon N

  14. Stress analysis of fatigue cracks in mechanically fastened joints : An analytical and experimental investigation

    NARCIS (Netherlands)

    De Rijck, J.J.M.


    The two historical fuselage failures, Comet in 1954 and Aloha in 1988, illustrate that similar accidents must be avoided which requires a profound understanding of the fatigue mechanisms involved, including analytical models to predict the fatigue behavior of riveted joints of a fuselage structure.

  15. Analysis of the stress-strain state in single overlap joints using piezo-ceramic actuators (United States)

    Pǎltânea, Veronica; Pǎltânea, Gheorghe; Popovici, Dorina; Jiga, Gabriel; Papanicolaou, George


    In this paper is presented a 2D approach to finite element modeling and an analytical calculus of a single lap bonded joint. As adherent material were selected a sheet of wood, aluminum and titanium. For adhesive part were selected Bison Super Wood D3 in case of the wood single lap joint and an epoxy resin type DGEBA-TETA for gluing together aluminum and titanium parts. In the article is described a combined method, which consists in the placement of the piezoelectric actuator inside of the adhesive part, in order to determine the tensile stress in the overlap joint. A comparison between the analytical and numerical results has been achieved through a multiphysics modeling - electrical and mechanical coupled problem. The technique used to calculate the mechanical parameters (First Principal Stress, displacements) was the three-point bending test, where different forces were applied in the mid-span of the structure, in order to maintain a constant displacement rate. The length of the overlap joint was modified from 20 to 50 mm.

  16. Cytologic analysis of synovial fluid in clinically normal tarsal joints of young camels (Camelus dromedarius). (United States)

    Al-Rukibat, R K; Bani Ismail, Z A; Al-Zghoul, M B


    Camels are important in the racing industry and for milk, meat, and hair production in the Middle East. Evaluation of synovial fluid is an important part of the assessment of musculoskeletal injuries in this species. Information in the literature regarding synovial fluid in camels is limited. The objective of this study was to determine the protein and cellular composition of synovial fluid from the tarsal joints of clinically normal, young camels (Camelus dromedarius). Thirty clinically healthy, male camels, aged 9 to 12 months, were used in the study. Synovial fluid samples were collected from the right and left tarsal joints. Samples were processed within 60 minutes after collection. Total nucleated cell counts (TNCC) were assessed using a hemacytometer. Total protein concentration was determined using a refractometer. Forty-six samples were analyzed. The TNCC (mean +/- SD) was 175.8 +/- 136.7 cells/microL (range 50-678 cells/microL). Differential cell percentages were obtained for lymphocytes (58.2 +/- 21.55%, range 15-90%), monocyte/macrophages (38.3 +/- 20.8%, range 10-85%), and neutrophils (3.5 +/- 5.1%, range 0-15%). Protein concentration was 2.1 +/- 0.6 g/dL (range 1-3 g/dL). Significant differences were not observed in any parameters between right and left tarsal joints. Synovial fluid reference values were established and may be useful in the clinical investigation of joint disease in young camels.

  17. Welded joints integrity analysis and optimization for fiber laser welding of dissimilar materials (United States)

    Ai, Yuewei; Shao, Xinyu; Jiang, Ping; Li, Peigen; Liu, Yang; Liu, Wei


    Dissimilar materials welded joints provide many advantages in power, automotive, chemical, and spacecraft industries. The weld bead integrity which is determined by process parameters plays a significant role in the welding quality during the fiber laser welding (FLW) of dissimilar materials. In this paper, an optimization method by taking the integrity of the weld bead and weld area into consideration is proposed for FLW of dissimilar materials, the low carbon steel and stainless steel. The relationships between the weld bead integrity and process parameters are developed by the genetic algorithm optimized back propagation neural network (GA-BPNN). The particle swarm optimization (PSO) algorithm is taken for optimizing the predicted outputs from GA-BPNN for the objective. Through the optimization process, the desired weld bead with good integrity and minimum weld area are obtained and the corresponding microstructure and microhardness are excellent. The mechanical properties of the optimized joints are greatly improved compared with that of the un-optimized welded joints. Moreover, the effects of significant factors are analyzed based on the statistical approach and the laser power (LP) is identified as the most significant factor on the weld bead integrity and weld area. The results indicate that the proposed method is effective for improving the reliability and stability of welded joints in the practical production.

  18. Limit analysis discussion of design methods for fracture of timber dowel joints loaded perpendicular to grain

    NARCIS (Netherlands)

    Van der Put, T.A.C.M.


    The results of an investigation of splitting of joints of [1] are used for a discussion of design methods and as necessary answer on comments and for confirmation of the extended fracture mechanics theory which accounts for the part of the external energy which is needed for plastic dissipation at

  19. Fabrication, testing and analysis of steel/composite DLS adhesive joints

    DEFF Research Database (Denmark)

    Nashim, S.; Nisar, J.; Tsouvalis, N.


    0/90 WR GFRP and 0/90 UD CFRP laminates and steel. The focus here is on CFRP/steel joint due to availability of test data. The thickness of the outer adherend varies from 3 mm to 6 mm. Shear overlaps of 25-200mm were considered. The overall objectives are (i) to assess the quality of the standard...

  20. Kinematic analysis and fault-tolerant trajectory planning of space manipulator under a single joint failure. (United States)

    Mu, Zonggao; Han, Liang; Xu, Wenfu; Li, Bing; Liang, Bin


    A space manipulator plays an important role in spacecraft capturing, repairing, maintenance, and so on. However, the harsh space environment will cause its joints fail to work. For a non-redundant manipulator, single joint locked failure will cause it to lose one degree of freedom (DOF), hence reducing its movement ability. In this paper, the key problems related to the fault-tolerant including kinematics, workspace, and trajectory planning of a non-redundant space manipulator under single joint failure are handled. First, the analytical inverse kinematics equations are derived for the 5-DOF manipulator formed by locking the failure joint of the original 6-DOF manipulator. Then, the reachable end-effector pose (position and orientation) is determined. Further, we define the missions can be completed by the 5-DOF manipulator. According to the constraints of the on-orbital mission, we determine the grasp envelope required for the end-effector. Combining the manipulability of the manipulator and the performance of its end-effector, a fault tolerance parameter is defined and a planning method is proposed to generate the reasonable trajectory, based on which the 5-DOF manipulator can complete the desired tasks. Finally, typical cases are simulated and the simulation results verify the proposed method.

  1. Generalised fracture mechanics approach to the interfacial failure analysis of a bonded steel-concrete joint

    Czech Academy of Sciences Publication Activity Database

    De Corte, W.; Helincks, P.; Boel, V.; Klusák, Jan; Seitl, Stanislav; De Schutter, G.


    Roč. 11, č. 42 (2017), s. 147-160 ISSN 1971-8993 R&D Projects: GA MŠk(CZ) LQ1601; GA ČR(CZ) GA16-18702S Institutional support: RVO:68081723 Keywords : Epoxy adhesive * Fracture mechanics * Interfacial properties * Numerical study * Push-out test * Steel-concrete joint Subject RIV: JL - Materials Fatigue, Friction Mechanics

  2. Gait analysis of transfemoral amputee patients using prostheses with two different knee joints

    NARCIS (Netherlands)

    Boonstra, AM; Schrama, JM; Eisma, WH; Hof, AL; Fidler, EV

    Objective: To evaluate the gait of transfemoral amputee patients using a prosthesis with a 4-bar linkage knee joint with either a mechanical swing phase control (Otto Beck 3R20) or a pneumatic swing phase control (Tehlin knee). Design: Randomized cross-over trial. Setting: Rehabilitation Department

  3. Analysis of a Joint Department of Veterans Affairs and Department of Defense Intensive Care Unit

    National Research Council Canada - National Science Library

    Malone, Danna


    ...) for a jointly staffed six-bed intensive care unit (ICU) at WHMC. The STVHCS can recruit and hire critical care nurses but has inadequate ICU bed capacity while WHMC has available ICU beds but insufficient nursing staff due to military deployments...

  4. An analysis of the possibility for health implications of joint actions and interactions between food additives

    NARCIS (Netherlands)

    Groten, J.P.; Butler, W.; Feron, V.J.; Kozianowski, G.; Renwick, A.G.; Walker, R.


    The possibility that structurally unrelated food additives could show either joint actions or interactions has been assessed based on their potential to share common sites and mechanisms of action or common pathways of elimination. All food additives approved in the European Union and allocated

  5. Joint action on mental health at the workplace : situation analysis and recommendation for action

    NARCIS (Netherlands)

    Fine, A.; Griffiths, J.; Breucker, G.; Sochert, R.; Knoche, K.; Zabrocki, H.; Heigi, C.; Radonic, E.; Mattila-Holappa, P.; Buffet, M.A.; Houtman, I.L.D.; Gründemann, R.; Hulleman, J.; Nijland, B.; Kramberger, B.; Betlehem, J.; Pék, E..; Ingudottir, J.; Bjarnadottir, S.; Murray, P.; Xerri, R.


    The thematic “Mental Health at Workplaces” is part of the “Joint Action on Mental Health and Well-being”, an initiative which sits within the framework of the 2 nd European Health Programme of the European Commission and the Member States of the EU in the period 2013 to 2016. The main aim of this

  6. Analysis of the talocrural and subtalar joint motions in patients with medial tibial stress syndrome. (United States)

    Akiyama, Kei; Noh, Byungjoo; Fukano, Mako; Miyakawa, Shumpei; Hirose, Norikazu; Fukubayashi, Toru


    The rearfoot motion during sports activities in patients with the medial tibial stress syndrome (MTSS) is unknown. This study aimed to investigate the difference in kinematics of the rearfoot in MTSS patients (eight male soccer players) and control participants (eight male soccer players) during a forward step. Sixteen male soccer players, including eight players with MTSS, participated. Forward step trials were recorded with cineradiographic images obtained at a sampling rate of 60 Hz. Geometric bone models of the tibia and talus/calcaneus were created from computed tomography scans of the distal part of one lower limb. Following a combination of approaches, anatomical coordinate systems were embedded in each bone model. The talocrural joint motion (relative motion of the talus with respect to the tibia) and subtalar joint motion (relative motion of the calcaneus with respect to the talus) were examined. A significantly larger range of internal/external rotation and inversion/eversion motion was observed in the subtalar joint of MTSS patients compared to healthy controls (P angles during the forward step. Our results indicate that the range of subtalar joint motion is greater in patients with MTSS during the stance phase of the forward step. The kinematic results obtained of this study may have important clinical implications and add quantitative data to an in vivo database of MTSS patients.

  7. Descriptive analysis of the economic costs of periprosthetic joint infection of the knee for the public health system of Andalusia. (United States)

    Garrido-Gómez, J; Arrabal-Polo, M A; Girón-Prieto, M S; Cabello-Salas, J; Torres-Barroso, J; Parra-Ruiz, J


    This study offers a descriptive analysis of the economic costs of Periprosthetic joint infection (PJI) of the knee for the public health system of Andalusia (Spain) The data are based on consecutive patients with PJI treated in our Bone and Joint Infection Unit between January 2005 and January 2010. The total cost for all patients with knee PJI was 4,151,843 $ (3,202,841 €), i.e., a mean cost per patient of 52,555 $ (40,542 €). The mean cost per patient was 24,980 $ (19,270.80 €) for patients with early PJI and rose to 78,111 $ (60,257 €) for those with late PJI. The main cost was for the hospital stay and the specific in-hospital care received, followed by the cost of the surgical procedure. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Startup analysis for a high temperature gas loaded heat pipe (United States)

    Sockol, P. M.


    A model for the rapid startup of a high-temperature gas-loaded heat pipe is presented. A two-dimensional diffusion analysis is used to determine the rate of energy transport by the vapor between the hot and cold zones of the pipe. The vapor transport rate is then incorporated in a simple thermal model of the startup of a radiation-cooled heat pipe. Numerical results for an argon-lithium system show that radial diffusion to the cold wall can produce large vapor flow rates during a rapid startup. The results also show that startup is not initiated until the vapor pressure p sub v in the hot zone reaches a precise value proportional to the initial gas pressure p sub i. Through proper choice of p sub i, startup can be delayed until p sub v is large enough to support a heat-transfer rate sufficient to overcome a thermal load on the heat pipe.

  9. Nonlinear temperature dependent failure analysis of finite width composite laminates (United States)

    Nagarkar, A. P.; Herakovich, C. T.


    A quasi-three dimensional, nonlinear elastic finite element stress analysis of finite width composite laminates including curing stresses is presented. Cross-ply, angle-ply, and two quasi-isotropic graphite/epoxy laminates are studied. Curing stresses are calculated using temperature dependent elastic properties that are input as percent retention curves, and stresses due to mechanical loading in the form of an axial strain are calculated using tangent modulii obtained by Ramberg-Osgood parameters. It is shown that curing stresses and stresses due to tensile loading are significant as edge effects in all types of laminate studies. The tensor polynomial failure criterion is used to predict the initiation of failure. The mode of failure is predicted by examining individual stress contributions to the tensor polynomial.

  10. Bridges Expansion Joints

    Directory of Open Access Journals (Sweden)

    Sergey W. Kozlachkow


    Full Text Available The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  11. Test and Analysis Correlation for a Y-Joint Specimen for a Composite Cryotank (United States)

    Mason, Brian H.; Sleight, David W.; Grenoble, Ray


    The Composite Cryotank Technology Demonstration (CCTD) project under NASA's Game Changing Development Program (GCDP) developed space technologies using advanced composite materials. Under CCTD, NASA funded the Boeing Company to design and test a number of element-level joint specimens as a precursor to a 2.4-m diameter composite cryotank. Preliminary analyses indicated that the y-joint in the cryotank had low margins of safety; hence the y-joint was considered to be a critical design region. The y-joint design includes a softening strip wedge to reduce localized shear stresses at the skirt/dome interface. In this paper, NASA-developed analytical models will be correlated with the experimental results of a series of positive-peel y-joint specimens from Boeing tests. Initial analytical models over-predicted the experimental strain gage readings in the far-field region by approximately 10%. The over-prediction was attributed to uncertainty in the elastic properties of the laminate and a mismatch between the thermal expansion of the strain gages and the laminate. The elastic properties of the analytical model were adjusted to account for the strain gage differences. The experimental strain gages also indicated a large non-linear effect in the softening strip region that was not predicted by the analytical model. This non-linear effect was attributed to delamination initiating in the softening strip region at below 20% of the failure load for the specimen. Because the specimen was contained in a thermally insulated box during cryogenic testing to failure, delamination initiation and progression was not visualized during the test. Several possible failure initiation locations were investigated, and a most likely failure scenario was determined that correlated well with the experimental data. The most likely failure scenario corresponded to damage initiating in the softening strip and delamination extending to the grips at final failure.

  12. Static Stability Analysis of a Planar Object Grasped by Multifingers with Three Joints

    Directory of Open Access Journals (Sweden)

    Takayoshi Yamada


    Full Text Available This paper discusses static stability of a planar object grasped by multifingers with three joints. Each individual joint (prismatic joint or revolute joint is modeled as a linear spring stiffness. The object mass and the link masses are also included. We consider not only pure rolling contact but also frictionless sliding contact. The grasp stability is investigated using the potential energy method. This paper makes the following contributions: (i Grasp wrench vectors and grasp stiffness matrices are analytically derived not only for the rolling contact but also for the sliding contact; (ii It is shown in detail that the vectors and the matrices are given by functions of grasp parameters such as the contact conditions (rolling contact and sliding contact, the contact position, the contact force, the local curvature, the link shape, the object mass, the link masses, and so on; (iii By using positive definiteness of the difference matrix of the grasp stiffness matrices, it is analytically proved that the rolling contact grasp is more stable than the sliding contact grasp. The displacement direction affected by the contact condition deviation is derived; (iv By using positive definiteness of the differential matrix with respect to the local curvatures, it is analytically proved that the grasp stability increases when the local curvatures decrease. The displacement direction affected by the local curvature deviation is also derived; (v Effects of the object mass and the joint positions are discussed using numerical examples. The numerical results are reinforced by analytical explanations. The effect of the link masses is also investigated.

  13. The effectiveness of orthoses in the conservative management of thumb CMC joint osteoarthritis: An analysis of functional pinch strength. (United States)

    Grenier, Marie-Lyne; Mendonca, Rochelle; Dalley, Peter


    The study was a retrospective cohort analysis for a 19-month period from May 2013 to December 2014. Although the use of orthoses has long been a staple of conservative treatment measures for individuals with osteoarthritis of the thumb carpometacarpal (CMC) joint, there remains little evidence exploring its effectiveness in improving functional outcomes for this client population. The purpose of this study was to assess the effectiveness of 3 frequently used orthoses in improving the functional pinch strength of adults with a diagnosis of thumb CMC joint osteoarthritis. A retrospective cohort analysis was conducted to determine whether pinch strength improved after orthotic fabrication, and fitting in patients referred to a hand therapy clinic. Patients who received a Colditz design orthosis had a mean increase of 2.64 lb with regard to functional pinch strength after orthotic fabrication and fitting. Patients who received a Comfort Cool orthosis (North Coast Medical, Morgan Hill, CA) had a mean increase of 2.47 lb, whereas patients who received a Thumb Spica orthosis had a mean increase of 3.25 lb. There was no evidence of any statistically significant difference in the average improvements in pinch strength between the Colditz design orthosis and the Comfort Cool orthosis. Results from this study demonstrate that orthosis wear consistently increases the functional pinch strength of individuals with thumb CMC joint osteoarthritis. Large-scale multisite research studies comparing various orthotic designs are necessary to help therapists determine best practice interventions for the conservative management of thumb CMC joint osteoarthritis. 2(c). Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  14. Analysis of risk factors for adjacent superior vertebral pedicle-induced facet joint violation during the minimally invasive surgery transforaminal lumbar interbody fusion: a retrospective study. (United States)

    Zeng, Zhi-Li; Jia, Long; Xu, Wei; Yu, Yan; Hu, Xiao; Jia, Yong-Wei; Wang, Jian-Jie; Cheng, Li-Ming


    The purpose was to explore possible risk factors of facet joint violation induced by adjacent superior vertebral pedicle screw during the minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF). A total of 69 patients with lumbar degenerative disease, who underwent MIS-TLIF were retrospectively reviewed. Postoperative computed tomography images were used to assess the facet joint violation. The correlation of facet joint violations with gender, age, body mass index (BMI), the adjacent superior vertebral level, fusion segment numbers, position of screw insertion, straight leg-raising test (SLRT) results, clinical diseases and renal dysfunction were analyzed by Chi-square tests and binary logistic regression analysis. The incidence of adjacent superior facet joint violations was 25.4 %. Chi-square test showed the patients with age violations (P = 0.007; P = 0.006). The single segment fusion presented more facet joint violations than the double segments fusion (P = 0.048). The vertebral pedicle screw implant location at L5 showed more facet joint violations compared with that at L3 and L4 (P = 0.035). No correlation was found between gender, screw implant position, SLRT results, clinical diseases and renal dysfunction and facet joint violations. Logistic regression analysis revealed that age violation. These results found a high incidence of adjacent superior vertebral facet joint violation in the MIS-TLIF. Age violation. Evidence level: Level 4.

  15. Joint analysis of expression profiles from multiple cancers improves the identification of microRNA–gene interactions (United States)

    Chen, Xiaowei; Slack, Frank J.; Zhao, Hongyu


    Motivation: MicroRNAs (miRNAs) play a crucial role in tumorigenesis and development through their effects on target genes. The characterization of miRNA–gene interactions will lead to a better understanding of cancer mechanisms. Many computational methods have been developed to infer miRNA targets with/without expression data. Because expression datasets are in general limited in size, most existing methods concatenate datasets from multiple studies to form one aggregated dataset to increase sample size and power. However, such simple aggregation analysis results in identifying miRNA–gene interactions that are mostly common across datasets, whereas specific interactions may be missed by these methods. Recent releases of The Cancer Genome Atlas data provide paired expression profiling of miRNAs and genes in multiple tumors with sufficiently large sample size. To study both common and cancer-specific interactions, it is desirable to develop a method that can jointly analyze multiple cancers to study miRNA–gene interactions without combining all the data into one single dataset. Results: We developed a novel statistical method to jointly analyze expression profiles from multiple cancers to identify miRNA–gene interactions that are both common across cancers and specific to certain cancers. The benefit of this joint analysis approach is demonstrated by both simulation studies and real data analysis of The Cancer Genome Atlas datasets. Compared with simple aggregate analysis or single sample analysis, our method can effectively use the shared information among different but related cancers to improve the identification of miRNA–gene interactions. Another useful property of our method is that it can estimate similarity among cancers through their shared miRNA–gene interactions. Availability and implementation: The program, MCMG, implemented in R is available at Contact: PMID:23772050

  16. [Finite element analysis on the effect of lateral wedge insole intervention on the contact characteristics of the subtalar joint]. (United States)

    Zhou, En-Chang; Tang, Ping; Zhu, Chuan-Ying; Liu, Shi-Ming


    To establish a three-dimensional finite element model of the lower limb bones, and investigate the changes of the contact characteristics of the subtalar joint after using laterally wedge insole intervention. Using the reverse modeling technology, the lower limb bones of normal adult volunteers was scanned by CT. Mimics 10.0 and Geomagic Studio 6.0 software were used to reconstruct the 3D morphology of bones and external soft tissue of the feet. The laterally wedge insole was designed in ProE 5.0. And then all the models were imported into Hyperwork 10.0 and meshed, and given the material properties. The finite element analysis was carried out in ABAQUS 6.9. A three-dimensional finite element model of the lower extremity was established, which was consisted of 95 365 nodes and 246 238 elements. The contact area of the standing state of the lower joint was larger than that of the anterior middle joint surface. The peak stress was concentrated in the anterior lateral part of the posterior articular surface, and the average stress value was(3.85±1.03) MPa. Compared with the model of 0°, the contact area of the subtalar joint was reduced accordingly. There was a significant correlation between anterior middle joint | r |=0.964, P =0.008, and posterior articular | r |=0.978, P =0.002. The equivalent stress of 0° model distributed from(3.07±1.14) MPa to(3.85± 1.03) MPa, which had no statistically difference. Compared with the 0° model, the equivalent stress of the anterior and middle joint surfaces of the 8° model was significantly reduced( P 0.05). Although a certain valgus can be obtained in subtalar by wearing LWI, the result comes at the cost of the stress concentration on posterior surface. Through this study, we can find that LWI with 8° tilt angle could provide appropriate valgus moment without causing excessive concentration. Therefore, in order to avoid secondary ankle complications, we should not increase the tilt angle blindly.

  17. Evaluation of RSA set-up from a clinical biplane fluoroscopy system for 3D joint kinematic analysis. (United States)

    Bonanzinga, Tommaso; Signorelli, Cecilia; Bontempi, Marco; Russo, Alessandro; Zaffagnini, Stefano; Marcacci, Maurilio; Bragonzoni, Laura


    dinamic roentgen stereophotogrammetric analysis (RSA), a technique currently based only on customized radiographic equipment, has been shown to be a very accurate method for detecting three-dimensional (3D) joint motion. The aim of the present work was to evaluate the applicability of an innovative RSA set-up for in vivo knee kinematic analysis, using a biplane fluoroscopic image system. To this end, the Authors describe the set-up as well as a possible protocol for clinical knee joint evaluation. The accuracy of the kinematic measurements is assessed. the Authors evaluated the accuracy of 3D kinematic analysis of the knee in a new RSA set-up, based on a commercial biplane fluoroscopy system integrated into the clinical environment. The study was organized in three main phases: an in vitro test under static conditions, an in vitro test under dynamic conditions reproducing a flexion-extension range of motion (ROM), and an in vivo analysis of the flexion-extension ROM. For each test, the following were calculated, as an indication of the tracking accuracy: mean, minimum, maximum values and standard deviation of the error of rigid body fitting. in terms of rigid body fitting, in vivo test errors were found to be 0.10±0.05 mm. Phantom tests in static and kinematic conditions showed precision levels, for translations and rotations, of below 0.1 mm/0.2° and below 0.5 mm/0.3° respectively for all directions. the results of this study suggest that kinematic RSA can be successfully performed using a standard clinical biplane fluoroscopy system for the acquisition of slow movements of the lower limb. a kinematic RSA set-up using a clinical biplane fluoroscopy system is potentially applicable and provides a useful method for obtaining better characterization of joint biomechanics.

  18. Kinematic Analysis of Gait Following Intra-articular Corticosteroid Injection into the Knee Joint with an Acute Exacerbation of Arthritis. (United States)

    Mehta, Saurabh; Shay, Barbara L; Szturm, Tony; El-Gabalawy, Hani S


    The objective of this study was to examine the effects of intra-articular corticosteroid injection (ICI) on ipsilateral knee flexion/extension, ankle dorsiflexion/plantarflexion (DF/PF), and hip abduction/adduction (abd/add) during stance phase in people with an acute exacerbation of rheumatoid arthritis (RA) of the knee joint. The study also assessed the effects of ICI on spatiotemporal parameters of gait and functional status in this group. Nine people with an exacerbation of RA of the knee were recruited. Kinematic and spatiotemporal gait parameters were obtained for each participant. Knee-related functional status was assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS). Spatiotemporal gait parameters and joint angles (knee flexion, ankle DF/PF, hip abd/add) of the affected side were compared pre- and post-ICI. Data for eight people were available for analysis. Median values for knee flexion and ankle PF increased significantly following ICI. Gait parameters of cadence, velocity, bilateral stride length, bilateral step length, step width, double-support percentage, and step time on the affected side also showed improvement. Pain and knee-related functional status as measured by the KOOS showed improvement. This study demonstrated a beneficial short-term effect of ICI on knee-joint movements, gait parameters, and knee-related functional status in people with acute exacerbation of RA of the knee.

  19. Kinematic Analysis of Gait Following Intra-articular Corticosteroid Injection into the Knee Joint with an Acute Exacerbation of Arthritis (United States)

    Mehta, Saurabh; Szturm, Tony; El-Gabalawy, Hani S.


    ABSTRACT Purpose: The objective of this study was to examine the effects of intra-articular corticosteroid injection (ICI) on ipsilateral knee flexion/extension, ankle dorsiflexion/plantarflexion (DF/PF), and hip abduction/adduction (abd/add) during stance phase in people with an acute exacerbation of rheumatoid arthritis (RA) of the knee joint. The study also assessed the effects of ICI on spatiotemporal parameters of gait and functional status in this group. Methods: Nine people with an exacerbation of RA of the knee were recruited. Kinematic and spatiotemporal gait parameters were obtained for each participant. Knee-related functional status was assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS). Spatiotemporal gait parameters and joint angles (knee flexion, ankle DF/PF, hip abd/add) of the affected side were compared pre- and post-ICI. Results: Data for eight people were available for analysis. Median values for knee flexion and ankle PF increased significantly following ICI. Gait parameters of cadence, velocity, bilateral stride length, bilateral step length, step width, double-support percentage, and step time on the affected side also showed improvement. Pain and knee-related functional status as measured by the KOOS showed improvement. Conclusions: This study demonstrated a beneficial short-term effect of ICI on knee-joint movements, gait parameters, and knee-related functional status in people with acute exacerbation of RA of the knee. PMID:22942516

  20. Finite helical axis for the analysis of joint kinematics: comparison of an electromagnetic and an optical motion capture system. (United States)

    Cescon, Corrado; Tettamanti, Andrea; Barbero, Marco; Gatti, Roberto


    The analysis of joints kinematics is important in clinical practice and in research. Nowadays it is possible to evaluate the mobility of joints in vivo with different motion capture techniques available in the market. Optical systems use infrared cameras and reflective markers to evaluate body movements, while other systems use electromagnetic fields to detect position and orientation of sensors. The aim of this study was the evaluation of two motion capture systems based on different technologies (optical and electromagnetic) by comparing the distribution of finite helical axis (FHA) of rotation during controlled rotations of an object in different positions. The distribution of position and angle errors of the FHA were extracted by optical and electromagnetic system recordings during a controlled rotation of a low friction stool in different positions in a controlled environment. The optical motion capture system showed lower angle and position errors in the distribution of FHA while the electromagnetic system had higher errors that increased with increasing distance from the antenna. The optical system showed lower errors in the estimation of FHA that could make it preferable with respect to electromagnetic systems during joint kinematics.

  1. The experience of family carers attending a joint reminiscence group with people with dementia: A thematic analysis. (United States)

    Melunsky, Nina; Crellin, Nadia; Dudzinski, Emma; Orrell, Martin; Wenborn, Jennifer; Poland, Fiona; Woods, Bob; Charlesworth, Georgina


    Reminiscence therapy has the potential to improve quality of life for people with dementia. In recent years reminiscence groups have extended to include family members, but carers' experience of attending joint sessions is undocumented. This qualitative study explored the experience of 18 family carers attending 'Remembering Yesterday Caring Today' groups. Semi-structured interviews were transcribed and subjected to thematic analysis. Five themes were identified: experiencing carer support; shared experience; expectations (met and unmet), carer perspectives of the person with dementia's experience; and learning and comparing. Family carers' experiences varied, with some experiencing the intervention as entirely positive whereas others had more mixed feelings. Negative aspects included the lack of respite from their relative, the lack of emphasis on their own needs, and experiencing additional stress and guilt through not being able to implement newly acquired skills. These findings may explain the failure of a recent trial of joint reminiscence groups to replicate previous findings of positive benefit. More targeted research within subgroups of carers is required to justify the continued use of joint reminiscence groups in dementia care. © The Author(s) 2013.

  2. Uncontrolled manifold analysis of arm joint angle variability during robotic teleoperation and freehand movement of surgeons and novices. (United States)

    Nisky, Ilana; Hsieh, Michael H; Okamura, Allison M


    Teleoperated robot-assisted surgery (RAS) is used to perform a wide variety of minimally invasive procedures. However, current understanding of the effect of robotic manipulation on the motor coordination of surgeons is limited. Recent studies in human motor control suggest that we optimize hand movement stability and task performance while minimizing control effort and improving robustness to unpredicted disturbances. To achieve this, the variability of joint angles and muscle activations is structured to reduce task-relevant variability and increase task-irrelevant variability. In this study, we determine whether teleoperation of a da Vinci Si surgical system in a nonclinical task of simple planar movements changes this structure of variability in experienced surgeons and novices. To answer this question, we employ the UnControlled manifold analysis that partitions users' joint angle variability into task-irrelevant and task-relevant manifolds. We show that experienced surgeons coordinate their joint angles to stabilize hand movements more than novices, and that the effect of teleoperation depends on experience--experts increase teleoperated stabilization relative to freehand whereas novices decrease it. We suggest that examining users' exploitation of the task-irrelevant manifold for stabilization of hand movements may be applied to: (1) evaluation and optimization of teleoperator design and control parameters, and (2) skill assessment and optimization of training in RAS.

  3. Rapid multicomponent T2 analysis of the articular cartilage of the human knee joint at 3.0T. (United States)

    Liu, Fang; Chaudhary, Rajeev; Hurley, Samuel A; Munoz Del Rio, Alejandro; Alexander, Andrew L; Samsonov, Alexey; Block, Walter F; Kijowski, Richard


    To determine the feasibility of using multicomponent-driven equilibrium single-shot observation of T1 and T2 (mcDESPOT) for evaluating the human knee joint at 3.0T and to investigate depth-dependent and regional-dependent variations in multicomponent T2 parameters within articular cartilage. mcDESPOT was performed on the knee joint of 10 asymptomatic volunteers at 3.0T. Single-component T2 relaxation time (T2single ), multicomponent T2 relaxation time for water tightly bound to proteoglycan (T2PG ) and bulk water loosely bound to the macromolecular matrix (T2BW ), and fraction of water tightly bound to proteoglycan (FPG ) were measured in eight cartilage subsections and within the superficial and deep layers of patellar cartilage. Statistical analysis was used to investigate depth-dependent and regional-dependent variations in parameters. There was lower (P = 0.001) T2single and T2PG and higher (P Multicomponent T2 parameters of the articular cartilage of the human knee joint can be measured at 3.0T using mcDESPOT and show depth-dependent and regional-dependent variations. Copyright © 2013 Wiley Periodicals, Inc.

  4. Crystal Plasticity Finite-Element Analysis of Deformation Behavior in Multiple-Grained Lead-Free Solder Joints (United States)

    Darbandi, P.; Bieler, T. R.; Pourboghrat, F.; Lee, Tae-kyu


    The elastic and plastic anisotropy of the tin phase in a Pb-free tin-based solder joint has a very important effect on the reliability of solder joints. The crystal plasticity finite-element (CPFE) method takes into account the effect of anisotropy, and it can be used to solve crystal mechanical deformation problems under complicated external and internal boundary conditions imposed by inter- and intragrain micromechanical interactions. In this study, experimental lap-shear test results from the literature are used to calibrate the CPFE model. The spatial neighbor orientation relationships of the crystals were assessed by studying four different sets of orientations using a very simple model to establish a basis for further development of the model. Average shear strain and Schmid factor analyses were applied to study the activity of slip systems. Further optimization of model parameters using comparisons with experiments will be needed to identify more suitable rules for stress evolution among the 10 slip systems in Sn. By suppression of some of the slip systems the CPFE model is able to simulate heterogeneous deformation phenomena that are similar to those observed in experiments. This work establishes a basis for an incremental model development strategy based upon experiments, modeling, and comparative analysis to establish model parameters that could predict the slip processes that lead to damage evolution in lead-free solder joints.

  5. Numerical analysis of the adherends with similar thickness on weld-bonded single lap aluminium joint

    Directory of Open Access Journals (Sweden)

    Li Jianli


    Full Text Available The effect of the adherend with similar thickness varied from 1 mm to 3 mm on the stress distribution in weld-bonded single lap aluminium joint was investigated using elasto-plastic finite element method (FEM. The results from the numerical simulation show that all the values of the peak stresses along the mid-bondline at the points near the both ends of the lap zone as well as the ones in the region of the nugget are increased when the adherend thickness increased. It is suggested that the adherend thickness of 2 mm to 2.5 mm be appropriate to optimize the stress distribution in the weld-bonded single lap aluminium joint.

  6. Analysis and test of bonded single lap joints with preformed adherends (United States)

    Sawyer, J. W.; Cooper, P. A.


    A theoretical and experimental study has been conducted to investigate the load transfer of a single lap joint where the adherends have been preformed so that the angle between the line of action of the applied in-plane force and the bond line is reduced. The preforming of the adherend reduces the moment resultant in the adherend at the edge of the overlap region which reduces both the maximum peel and shear stresses in the adhesive, and gives a more uniform shear distribution in the adhesive. An increase in static load transfer of up to 120 percent has been shown, and several orders of magnitude increase in fatigue life have been achieved with modest preform angles. Thus, sizeable benefits can be obtained in the fatigue life or additional load capacity of bonded single lap joints by preforming the adherends.

  7. [Principles and experimental analysis of a measuring system for measuring spacesuit joint's damping parameters]. (United States)

    Wang, Hao; Jin, Ming-he; Liu, Hong; Gao, Xiao-hui; Li, Tan-qiu; Zhao, Yong-jun


    To measure the damping parameters of the spacesuit joint. The principles of the passive robot system for measuring spacesuit joint's damping parameters were presented. Basing on its special mechanical structure, a 3 DOF model of the flexible IVA (intra-vehicular activity) spacesuit's sleeve was built. The optimal approximation of inverse calculation based on 6 dimension space interval was described. The damping parameters of an actual IVA spacesuit's sleeve were measured on the actual testbed. Also, the potential application of the measuring system was discussed. The model of spacesuit sleeve and the forward/inverse kinematics were proved by experimental measurements and real time 3D simulation. The principles and the proposed method of the measurement were testified.

  8. Microbiota analysis to reveal temperature abuse of fresh pork

    DEFF Research Database (Denmark)

    Buschhardt, Tasja; Bahl, Martin Iain; Hansen, Tina Beck

    whether temperature induced changes in the community composition on fresh meat surfaces can reflect the temperature-history (combination of time and temperature). Sterile pieces of pork were inoculated with a carcass swab homogenate, to which Salmonella was added. Changes in the meat microbiota were...

  9. Microbiota analysis to reveal temperature abuse of fresh pork

    DEFF Research Database (Denmark)

    Buschhardt, Tasja; Bahl, Martin Iain; Hansen, Tina Beck


    whether temperature induced changes in the community composition on fresh meat surfaces can reflect the temperature-history (combination of time and temperature). Sterile pieces of pork were inoculated with a carcass swab homogenate, to which Salmonella was added. Changes in the meat microbiota were...

  10. Performance analysis of joint diversity combining, adaptive modulation, and power control schemes

    KAUST Repository

    Qaraqe, Khalid A.


    Adaptive modulation and diversity combining represent very important adaptive solutions for future generations of wireless communication systems. Indeed, in order to improve the performance and the efficiency of these systems, these two techniques have been recently used jointly in new schemes named joint adaptive modulation and diversity combining (JAMDC) schemes. Considering the problem of finding low hardware complexity, bandwidth-efficient, and processing-power efficient transmission schemes for a downlink scenario and capitalizing on some of these recently proposed JAMDC schemes, we propose and analyze in this paper three joint adaptive modulation, diversity combining, and power control (JAMDCPC) schemes where a constant-power variable-rate adaptive modulation technique is used with an adaptive diversity combining scheme and a common power control process. More specifically, the modulation constellation size, the number of combined diversity paths, and the needed power level are jointly determined to achieve the highest spectral efficiency with the lowest possible processing power consumption quantified in terms of the average number of combined paths, given the fading channel conditions and the required bit error rate (BER) performance. In this paper, the performance of these three JAMDCPC schemes is analyzed in terms of their spectral efficiency, processing power consumption, and error-rate performance. Selected numerical examples show that these schemes considerably increase the spectral efficiency of the existing JAMDC schemes with a slight increase in the average number of combined paths for the low signal-to-noise ratio range while maintaining compliance with the BER performance and a low radiated power which yields to a substantial decrease in interference to co-existing users and systems. © 2011 IEEE.

  11. Ideal Compliant Joints and Integration of Computer Aided Design and Analysis (United States)


    many MBS applications ( Vallejo et al., 2003; Hamed et al, 2011; Shabana et al, 2012). This can be achieved using ANCF finite elements which allow for...mechanical joints between finite elements can be formulated using linear connectivity conditions ( Vallejo et al., 2003; Hamed et al, 2011; Shabana...function of the damping stress dσ and the strain rate ε as ( Vallejo et al, 2005)  V dd dVP 2 1 T εσ

  12. Gait Analysis of Foot Compensation After Arthrodesis of the First Metatarsophalangeal Joint. (United States)

    Stevens, Jasper; Meijer, Kenneth; Bijnens, Wouter; Fuchs, Mathijs C H W; van Rhijn, Lodewijk W; Hermus, Joris P S; van Hoeve, Sander; Poeze, Martijn; Witlox, Adhiambo M


    Arthrodesis of the first metatarsophalangeal (MTP1) joint is an intervention often used in patients with severe MTP1 joint osteoarthritis and relieves pain in approximately 80% of these patients. The kinematic effects and compensatory mechanism of the foot for restoring a more normal gait pattern after this intervention are unknown. The aim of this study was to clarify this compensatory mechanism, in which it was hypothesized that the hindfoot and forefoot would be responsible for compensation after an arthrodesis of the MTP1 joint. Gait properties were evaluated in 10 feet of 8 patients with MTP1 arthrodesis and were compared with 21 feet of 12 healthy subjects. Plantar pressures and intersegmental range of motion were measured during gait by using the multisegment Oxford Foot Model. Pre- and postoperative X-rays of the foot and ankle were also evaluated. The MTP1 arthrodesis caused decreased eversion of the hindfoot during midstance, followed by an increased internal rotation of the hindfoot during terminal stance, and ultimately more supination and less adduction of the forefoot during preswing. In addition, MTP1 arthrodesis resulted in a lower pressure time integral beneath the hallux and higher peak pressures beneath the lesser metatarsals. A mean dorsiflexion fusion angle of 30 ± 5.4 degrees was observed in postoperative radiographs. This study demonstrated that the hindfoot and forefoot compensated for the loss of motion of the MTP1 joint after arthrodesis in order to restore a more normal gait pattern. This resulted in a gait in which the rigid hallux was less loaded while the lesser metatarsals endured higher peak pressures. Further studies are needed to investigate whether this observed transfer of load or a preexistent decreased compensatory mechanism of the foot can possibly explain the disappointing results in the minority of the patients who experience persistent complaints after a MTP1 arthrodesis. Level III, comparative series.

  13. Finite element analysis of mechanical behavior of human dysplastic hip joints: a systematic review. (United States)

    Vafaeian, B; Zonoobi, D; Mabee, M; Hareendranathan, A R; El-Rich, M; Adeeb, S; Jaremko, J L


    Developmental dysplasia of the hip (DDH) is a common condition predisposing to osteoarthritis (OA). Especially since DDH is best identified and treated in infancy before bones ossify, there is surprisingly a near-complete absence of literature examining mechanical behavior of infant dysplastic hips. We sought to identify current practice in finite element modeling (FEM) of DDH, to inform future modeling of infant dysplastic hips. We performed multi-database systematic review using PRISMA criteria. Abstracts (n = 126) fulfilling inclusion criteria were screened for methodological quality, and results were analyzed and summarized for eligible articles (n = 12). The majority of the studies modeled human adult dysplastic hips. Two studies focused on etiology of DDH through simulating mechanobiological growth of prenatal hips; we found no FEM-based studies in infants or children. Finite element models used either patient-specific geometry or idealized average geometry. Diversities in choice of material properties, boundary conditions, and loading scenarios were found in the finite-element models. FEM of adult dysplastic hips demonstrated generally smaller cartilage contact area in dysplastic hips than in normal joints. Contact pressure (CP) may be higher or lower in dysplastic hips depending on joint geometry and mechanical contribution of labrum (Lb). FEM of mechanobiological growth of prenatal hip joints revealed evidence for effects of the joint mechanical environment on formation of coxa valga, asymmetrically shallow acetabulum and malformed femoral head associated with DDH. Future modeling informed by the results of this review may yield valuable insights into optimal treatment of DDH, and into how and why OA develops early in DDH. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  14. Joint preservation after hip arthroscopy in patients with FAI. Prospective analysis with a minimum follow-up of seven years. (United States)

    Comba, Fernando; Yacuzzi, Carlos; Ali, Pablo J; Zanotti, Gerardo; Buttaro, Martin; Piccaluga, Francisco


    The purpose of this study is to evaluate the clinical outcomes, radiological degenerative progression and the joint preservation rate in a series of patients with Femoroacetabular Impingement (FAI) treated with hip arthroscopy at a minimum follow-up of 7 years. The predictive factors for total hip arthroplasty (THA) requirement were analyzed. Between February 2008 and February 2009, 42 consecutive patients treated with hip arthroscopy due to FAI syndrome were included. There were 15 women and 27 men with an average age of 38 years (range 23 to 56 years). The surgery involved joint damage stabilization (labral tears and/or chondrolabral injuries) and correction of associated bony deformities (cam and/or pincer lesions). A prospective clinical follow-up was made with no patient lost. We specifically addressed the need for THA. Predictive factors for THA were also analyzed. At final follow up, joint preservation rate was 83.33% (CI 95% 68,64%-93,03%). Probability of evolving to a THA in patients with radiographic preoperative Tonnis grades 0 and I was of 0% (CI 95%: 0-12.77). Probability of evolving to a THA in patients with preoperative Tonnis grades II and III was 46,67% (CI 95%21.27%-73,41%). A statistically significant difference was present between both groups (p= 0.002). Patients older than 45 years at the time of hip arthroscopy were at significant risk of evolving to a THA (p=0.0012). Excluding those patients who undergone a THA: modified HHS was 88.25 points (80-96) and radiographic analysis addressed a 14,29% (IC95% 4,81%-30,26%) of progressive degenerative changes without affecting clinical results. Hip arthroscopy for the treatment of patients with FAI syndrome showed favorable results regarding joint preservation. Patients with preoperative radiographic evidence of advanced-stage osteoarthritis and those older than 45 years at the time of surgery have higher risk of requiring THA. IV.

  15. Wear Resistance Analysis of A359/SiC/20p Advanced Composite Joints Welded by Friction Stir Welding

    Directory of Open Access Journals (Sweden)

    O. Cuevas Mata

    Full Text Available Abstract Advancement in automotive part development demands new cost-effective materials with higher mechanical properties and improved wear resistance as compared to existing materials. For instance, Aluminum Matrix Composites (AMC shows improved mechanical properties as wear and abrasion resistance, high strength, chemical and dimensional stability. Automotive industry has focused in AMC for a variety of applications in automotive parts in order to improve the fuel economy, minimize vehicle emissions, improve design options, and increase the performance. Wear resistance is one of the most important factors in useful life of the automotive components, overall in those components submitted to mechanical systems like automotive brakes and suspensions. Friction Stir Welding (FSW rises as the most capable process to joining AMC, principally for the capacity to weld without compromising their ceramic reinforcement. The aim of this study is focused on the analysis of wear characteristics of the friction-stir welded joint of aluminum matrix reinforced with 20 percent in weight silicon carbide composite (A359/SiC/20p. The experimental procedure consisted in cut samples into small plates and perform three welds on these with a FSW machine using a tool with 20 mm shoulder diameter and 8 mm pin diameter. The wear features of the three welded joints and parent metal were analyzed at constant load applying 5 N and a rotational speed of 100 rpm employing a Pin-on - Disk wear testing apparatus, using a sapphire steel ball with 6 mm diameter. The experimental results indicate that the three welded joints had low friction coefficient compared with the parent metal. The results determine that the FSW process parameters affect the wear resistance of the welded joints owing to different microstructural modifications during welding that causes a low wear resistance on the welded zone.

  16. Finite Element Analysis of Composite Joint Configurations with Gaps and Overlaps (United States)

    Krueger, Ronald


    The goal of the current study is to identify scenarios for which thermal and moisture effects become significant in the loading of a composite structure. In the current work, a simple configuration was defined, and material properties were selected. A Fortran routine was created to automate the mesh generation process. The routine was used to create the models for the initial mesh refinement study. A combination of element length and width suitable for further studies was identified. Also, the effect of the overlap length and gap length on computed shear and through-thickness stresses along the bondline of the joints was studied for the mechanical load case. Further, the influence of neighboring gaps and overlaps on these joint stresses was studied and was found to be negligible. The results suggest that for an initial study it is sufficient to focus on one configuration with fixed overlap and gap lengths to study the effects of mechanical, thermal and moisture loading and combinations thereof on computed joint stresses

  17. Analysis of Deformation and Failure Behaviors of TIG Welded Dissimilar Metal Joints Using Miniature Tensile Specimens

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji-Hwan; Jahanzeb, Nabeel; Kim, Min-Seong; Hwang, Ji-Hyun; Choi, Shi-Hoon [Sunchon National University, Suncheon (Korea, Republic of)


    The deformation and failure behaviors of dissimilar metal joints between SS400 steel and STS316L steel were investigated. The dissimilar metal joints were fabricated using the tungsten inert gas (TIG) welding process with STS309 steel as a filler metal. The microstructures of the dissimilar metal joints were investigated using an optical microscope and EBSD technique. The mechanical properties of the base metal (BM), heat affected zone (HAZ) and weld metal (WM) were measured using a micro-hardness and micro-tension tester combined with the digital image correlation (DIC) technique. The HAZ of the STS316L steel exhibited the highest micro-hardness value, and yield/tensile strengths, while the BM of the SS440 steel exhibited the lowest micro-hardness value and yield /tensile strengths. The grain size refinement in the HAZ of SS400 steel induced an enhancement of micro-hardness value and yield/tensile strengths compared to the BM of the SS400 steel. The WM, which consists of primary δ-ferrite and a matrix of austenite phase, exhibited relatively a high micro-hardness value, yield /tensile strengths and elongation compared to the BM and HAZ of the SS400 steel.

  18. Analysis of singular interface stresses in dissimilar material joints for plasma facing components (United States)

    You, J. H.; Bolt, H.


    Duplex joint structures are typical material combinations for the actively cooled plasma facing components of fusion devices. The structural integrity under the incident heat loads from the plasma is one of the most crucial issues in the technology of these components. The most critical domain in a duplex joint component is the free surface edge of the bond interface between heterogeneous materials. This is due to the fact that the thermal stress usually shows a singular intensification in this region. If the plasma facing armour tile consists of a brittle material, the existence of the stress singularity can be a direct cause of failure. The present work introduces a comprehensive analytical tool to estimate the impact of the stress singularity for duplex PFC design and quantifies the relative stress intensification in various materials joints by use of a model formulated by Munz and Yang. Several candidate material combinations of plasma facing armour and metallic heat sink are analysed and the results are compared with each other.

  19. Influence analysis for skew-normal semiparametric joint models of multivariate longitudinal and multivariate survival data. (United States)

    Tang, An-Min; Tang, Nian-Sheng; Zhu, Hongtu


    The normality assumption of measurement error is a widely used distribution in joint models of longitudinal and survival data, but it may lead to unreasonable or even misleading results when longitudinal data reveal skewness feature. This paper proposes a new joint model for multivariate longitudinal and multivariate survival data by incorporating a nonparametric function into the trajectory function and hazard function and assuming that measurement errors in longitudinal measurement models follow a skew-normal distribution. A Monte Carlo Expectation-Maximization (EM) algorithm together with the penalized-splines technique and the Metropolis-Hastings algorithm within the Gibbs sampler is developed to estimate parameters and nonparametric functions in the considered joint models. Case deletion diagnostic measures are proposed to identify the potential influential observations, and an extended local influence method is presented to assess local influence of minor perturbations. Simulation studies and a real example from a clinical trial are presented to illustrate the proposed methodologies. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Temperature analysis with voltage-current time differential operation of electrochemical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Leta Yar-Li; Glass, Robert Scott; Fitzpatrick, Joseph Jay; Wang, Gangqiang; Henderson, Brett Tamatea; Lourdhusamy, Anthoniraj; Steppan, James John; Allmendinger, Klaus Karl


    A method for temperature analysis of a gas stream. The method includes identifying a temperature parameter of an affected waveform signal. The method also includes calculating a change in the temperature parameter by comparing the affected waveform signal with an original waveform signal. The method also includes generating a value from the calculated change which corresponds to the temperature of the gas stream.

  1. Creep of timber joints

    NARCIS (Netherlands)

    Van de Kuilen, J.W.G.


    A creep analysis has been performed on nailed, toothed-plates and split-ring joints in a varying uncontrolled climate. The load levels varied between 30% and 50% of the average ultimate short term strength of these joints, tested in accordance with ISO 6891. The climate in which the tests were

  2. Process for forming unusually strong joints between metals and ceramics by brazing at temperatures that do not exceed 750/sup 0/C (United States)

    Hammond, J.P.; David, S.A.; Woodhouse, J.J.


    This invention is a process for joining metals to ceramics to form very strong bonds using low brazing temperature, i.e., less than 750/sup 0/C, and particularly for joining nodular cast iron to partially stabilized zirconia. The process provides that the ceramic be coated with an active metal, such as titanium, that can form an intermetallic with a low melting point brazing alloy such as 60Ag-30Cu-10Sn. The nodular cast iron is coated with a noncarbon containing metal, such as copper, to prevent carbon in the nodular cast iron from dissolving in the brazing alloy. These coated surfaces can be brazed together with the brazing alloy between at less than 750/sup 0/C to form a very strong joint. An even stronger bond can be formed if a transition piece is used between the metal and ceramic. It is preferred for the transition piece to have a coefficient of thermal expansion compatible with the coefficient of thermal expansion of the ceramic, such as titanium.

  3. Finite strain anisotropic elasto-plastic model for the simulation of the forming and testing of metal/short fiber reinforced polymer clinch joints at room temperature (United States)

    Dean, A.; Rolfes, R.; Behrens, A.; Bouguecha, A.; Hübner, S.; Bonk, C.; Grbic, N.


    There is a strong trend in the automotive industry to reduce car body-, chassis- and power-train mass in order to lower carbon emissions. More wide spread use of lightweight short fiber reinforced polymer (SFRP) is a promising approach to attain this goal. This poses the challenge of how to integrate new SFRP components by joining them to traditional sheet metal structures. Recently (1), the clinching technique has been successfully applied as a suitable joining method for dissimilar material such as SFRP and Aluminum. The material pairing PA6GF30 and EN AW 5754 is chosen for this purpose due to their common application in industry. The current contribution presents a verification and validation of a finite strain anisotropic material model for SFRP developed in (2) for the FE simulation of the hybrid clinching process. The finite fiber rotation during forming and separation, and thus the change of the preferential material direction, is represented in this model. Plastic deformations in SFRP are considered in this model via an invariant based non-associated plasticity formulation following the multiplicative decomposition approach of the deformation gradient where the stress-free intermediate configuration is introduced. The model allows for six independent characterization curves. The aforementioned material model allows for a detailed simulation of the forming process as well as a simulative prediction of the shear test strength of the produced joint at room temperature.

  4. The Experimental Analysis of Forming and Strength of Clinch Riveting Sheet Metal Joint Made of Different Materials

    Directory of Open Access Journals (Sweden)

    Jacek Mucha


    Full Text Available The paper presents the pressed joint technology using forming process with or without additional fastener. The capabilities for increasing the load-carrying ability of mechanical joints by applying special rivets and dies were presented. The experimental research focused on joining steel sheet metal made of different materials. The joint forming was performed with the solid round die and rectangular split die for riveted joint forming. The load-carrying ability of joints was evaluated by measuring the maximum load force in the shearing test in the tensile testing machine. The effect of joint forming process on joined material strain was compared by measuring the microhardness of the joints.

  5. Joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

  6. Thermomechanical analysis of Natural Rubber behaviour stressed at room temperature.

    Directory of Open Access Journals (Sweden)

    Chrysochoos A.


    Full Text Available Owing to their high molecular mobility, stressed rubber chains can easily change their conformations and get orientated. This phenomena leads to so high reversible draw ratio that this behaviour is called rubber elasticity [1-3]. The analogy with ideal gases leads to an internal energy independent of elongation, the stress being attributed to a so-called configuration entropy. However, this analysis cannot take thermal expansion into account and moreover prohibits predicting standard thermo-elastic effect noticed at small elongations and the thermoelastic inversion effects [4]. This paper aims at : observing and quantifying dissipative and coupling effects associated with deformation energy, generated when Natural Rubber is stretched. re-examine the thermomechanical behaviour model of rubberlike materials, under the generalised standard material concept. From an experimental viewpoint, energy balance is created using infrared and quantitative imaging techniques. Digital Image Correlation (DIC provides in-the-plane displacement fields and, after derivation, strain and strain-rate fields. We have used those techniques to evidence the thermoelastic inversion effect as shown on Figure 1 where different weights have been fixed to warmed specimen and we monitored the sample deformation while it recovers room temperature. But we have also used those techniques to perform energy balance : analysis of the mechanical equilibrium allows estimates of the stress pattern and computation of deformation energy rates under a plane stress hypothesis [5]. Infrared Thermography (IRT gives the surface temperature of the sample. To estimate the distribution of heat sources, image processing with a local heat equation and a minimal set of approximation functions (image filtering was used. The time courses of deformation energy and heat associated with cyclic process are plotted in Figure 2. The time derivatives of both forms of energy are approximately similar. This

  7. Joint Disorders (United States)

    A joint is where two or more bones come together, like the knee, hip, elbow, or shoulder. Joints can be damaged by many types of injuries or diseases, including Arthritis - inflammation of a joint. It causes pain, stiffness, and swelling. Over time, ...

  8. Lorentz invariance violation in the neutrino sector: a joint analysis from big bang nucleosynthesis and the cosmic microwave background

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Wei-Ming; Cai, Rong-Gen [Chinese Academy of Sciences, CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, P.O. Box 2735, Beijing (China); University of Chinese Academy of Sciences, School of Physical Sciences, Beijing (China); Guo, Zong-Kuan [Chinese Academy of Sciences, CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, P.O. Box 2735, Beijing (China); University of Chinese Academy of Sciences, School of Astronomy and Space Science, Beijing (China); Zhang, Yuan-Zhong [Chinese Academy of Sciences, CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, P.O. Box 2735, Beijing (China)


    We investigate constraints on Lorentz invariance violation in the neutrino sector from a joint analysis of big bang nucleosynthesis and the cosmic microwave background. The effect of Lorentz invariance violation during the epoch of big bang nucleosynthesis changes the predicted helium-4 abundance, which influences the power spectrum of the cosmic microwave background at the recombination epoch. In combination with the latest measurement of the primordial helium-4 abundance, the Planck 2015 data of the cosmic microwave background anisotropies give a strong constraint on the deformation parameter since adding the primordial helium measurement breaks the degeneracy between the deformation parameter and the physical dark matter density. (orig.)

  9. Lorentz invariance violation in the neutrino sector: a joint analysis from big bang nucleosynthesis and the cosmic microwave background (United States)

    Dai, Wei-Ming; Guo, Zong-Kuan; Cai, Rong-Gen; Zhang, Yuan-Zhong


    We investigate constraints on Lorentz invariance violation in the neutrino sector from a joint analysis of big bang nucleosynthesis and the cosmic microwave background. The effect of Lorentz invariance violation during the epoch of big bang nucleosynthesis changes the predicted helium-4 abundance, which influences the power spectrum of the cosmic microwave background at the recombination epoch. In combination with the latest measurement of the primordial helium-4 abundance, the Planck 2015 data of the cosmic microwave background anisotropies give a strong constraint on the deformation parameter since adding the primordial helium measurement breaks the degeneracy between the deformation parameter and the physical dark matter density.

  10. Morphometric analysis for evaluating the relation between incisal guidance angle, occlusal plane angle, and functional temporomandibular joint shape variation. (United States)

    Han, Seulgi; Shin, Sang Min; Choi, Yong-Seok; Kim, So Yeun; Ko, Ching-Chang; Kim, Yong-Il


    The correlations between morphology of the temporomandibular joint structure, the anterior guidance angle, and occlusal plane were investigated. A cone beam computed tomography analysis was performed in 158 patients (86 women and 72 men). 3D software was employed to obtain the coordinates of the shape of the incisal guidance angle, occlusal guidance angle, articular fossa, and mandibular condyle. Generalized Procrustes analysis including principal components analysis (PCA) were performed and produced principal components (PCs) scores of each shape and their centroid size (CS). A significant Pearson correlation coefficient of 0.3451 (p angle and occlusal plane. The CS also showed a correlation with the incisal guidance angle, but not with the occlusal plane angle. The PCA results revealed that there were no significant correlations between the temporomandibular joint structure (TMJ) shape (fossa and condyle) and the incisal guidance angle. Incisor guidance angle and occlusal plane angle were correlated. In addition, there was a correlation between CS and incisal guidance angle. In the PCA, It can be concluded that the size is more related to the incisor guidance angle than the morphological factors of the constituent components of the TMJ.

  11. The Consumers Characteristics Analysis of Low Temperature Home Delivery

    Directory of Open Access Journals (Sweden)

    Shu-Fang Lai


    Full Text Available Because of technological advancements and the popularity of the Internet, online shopping has become an important shopping channel for consumers. Because people increasingly eat out, more consumers shop online, and food products are collected from convenience stores, or frozen food home delivery services are used. This study used questionnaire surveys to analyze the consumption habits of residents who shop online for frozen foods in the urban areas of northern Taiwan (Taipei City and New Taipei City. We distributed and collected 548 questionnaires, of which 484 were valid. Descriptive statistics, a chi-square test, and logistics regression analysis were used to analyze consumer characteristics, as well as important influential factors. The research results indicated that most online shoppers were women, and the top 3 factors influencing their purchasing decisions were freshness, delivery convenience, and ordering convenience. Participants in the age group of 40-49 years old, living in the urban area of New Taipei City, without junior college education, and with less than 10,000 NTD monthly incomes, were less likely to purchase frozen foods using low-temperature logistics services.

  12. Analysis of heat exchanger network for temperature fluctuation

    Directory of Open Access Journals (Sweden)

    Jin Zunlong


    Full Text Available Subject to temperature disturbance, exchangers in heat exchanger network will interact. It is necessary to evaluate the degree of temperature fluctuation in the network. There is inherently linear relationship between output and inlet temperatures of heat exchanger network. Based on this, the concept of temperature-change sensitivity coefficient was put forward. Quantitative influence of temperature fluctuation in the network was carried out in order to examine transmission character of temperature fluctuation in the system. And the information was obtained for improving the design quality of heat exchanger network. Favorable results were obtained by the introduced method compared with the experimental results. These results will assist engineers to distinguish primary and secondary influencing factors, which can be used in observing and controlling influencing factors accurately.

  13. GHRSST Level 4 RAMSSA Australian Regional Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  14. GHRSST Level 4 GAMSSA Global Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  15. GHRSST Level 4 OSPO Global Foundation Sea Surface Temperature Analysis (GDS version 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  16. GHRSST Level 4 ODYSSEA Global Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  17. GHRSST Level 4 ODYSSEA Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  18. GHRSST Level 4 OSPO Global Nighttime Foundation Sea Surface Temperature Analysis (GDS version 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  19. GHRSST Level 4 DMI_OI Global Foundation Sea Surface Temperature Analysis (GDS version 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the Danish...

  20. GHRSST Level 4 MUR North America Regional Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced as a retrospective dataset at the JPL Physical...

  1. GHRSST Level 4 OSTIA Global Foundation Sea Surface Temperature Analysis (GDS versions 1 and 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the UK Met Office...

  2. GHRSST Level 4 EUR Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily by Ifremer/CERSAT (France) using optimal...

  3. Climate Prediction Center(CPC)Ensemble Canonical Correlation Analysis Forecast of Temperature (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ensemble Canonical Correlation Analysis (ECCA) temperature forecast is a 90-day (seasonal) outlook of US surface temperature anomalies. The ECCA uses Canonical...

  4. GHRSST Level 4 ODYSSEA Eastern Central Pacific Regional Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  5. GHRSST Level 4 K10_SST Global 1 meter Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Naval...

  6. GHRSST Level 4 G1SST Global Foundation Sea Surface Temperature Analysis (GDS version 1) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the JPL OurOcean...

  7. GHRSST Level 4 MW_OI Global Foundation Sea Surface Temperature analysis (GDS version 2) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at Remote Sensing...

  8. Treatment efficacy of lower eyelid twitch shift joint outer canthal ligament shortening surgery in degenerative analysis

    Directory of Open Access Journals (Sweden)

    Jun Shao


    Full Text Available AIM: To observe and compare efficacy of the lower eyelid twitch shift joint outer canthal ligament shortening surgery and orbicularis muscle resection surgery to treat degenerative entropion. METHODS: Patients with degenerative entropion in our hospital were selected. The test group was 40 cases(70 eyes, of which double eyes with attack(30 cases, and lower eyelid twitch shift joint outer canthal ligament shortening surgery was applied to the test group. Control group was 20 cases(26 eyes, of which double eyes with attack(6 cases, and the control group was used by orbicularis muscle resection surgery. The correction rate, double eyelid symmetry and overcorrection rate were observed in two groups at postoperative 1wk. The long- term recurrence rate, double eyelid symmetry and overcorrection rate with follow-up 6mo were observed. RESULTS: After 1wk, the correction rate of experimental group 98.6%,undercorrection rate of that was 1.4%, all the eyelid was symmetry, only one eye with a slight overcorrection. Correction rate of control group was 92.3%; all the eyelid was symmetry, and the poor rate of this group was 7.7%. After 6mo, correction rate of experimental group was 95.2%; undercorrection rate of experimental group was 3.2%, and overcorrection rate was 1.6%. Correction rate of control group was 87%, and 2 eyes of recurrence, 1 eye with a poor overcorrection. Double eyelid was symmetry, overcorrection rate difference was not statistically significant(P>0.05, and the correction rate were significantly different(PCONCLUSION: Compared toorbicularis muscle resection surgery, postoperative recurrence rate of lower eyelid twitch shift joint outer canthal ligament shortening surgery is significantly lowered.

  9. Biomechanical analysis of acromioclavicular joint dislocation repair using coracoclavicular suspension devices in two different configurations. (United States)

    Abat, Ferran; Sarasquete, Juan; Natera, Luis Gerardo; Calvo, Ángel; Pérez-España, Manuel; Zurita, Néstor; Ferrer, Jesús; del Real, Juan Carlos; Paz-Jimenez, Eva; Forriol, Francisco


    The best treatment option for some acromioclavicular (AC) joint dislocations is controversial. For this reason, the aim of this study was to evaluate the vertical biomechanical behavior of two techniques for the anatomic repair of coracoclavicular (CC) ligaments after an AC injury. Eighteen human cadaveric shoulders in which repair using a coracoclavicular suspension device was initiated after injury to the acromioclavicular joint were included in the study. Three groups were formed; group I (n = 6): control; group II (n = 6): repair with a double tunnel in the clavicle and in the coracoid (with two CC suspension devices); group III (n = 6): repair in a "V" configuration with two tunnels in the clavicle and one in the coracoid (with one CC suspension device). The biomechanical study was performed with a universal testing machine (Electro Puls 3000, Instron, Boulder, MA, USA), with the clamping jaws set in a vertical position. The force required for acromioclavicular reconstruction system failure was analyzed for each cadaveric piece. Group I reached a maximum force to failure of 635.59 N (mean 444.0 N). The corresponding force was 939.37 N (mean 495.6 N) for group II and 533.11 N (mean 343.9 N) for group III. A comparison of the three groups did not find any significant difference despite the loss of resistance presented by group III. Anatomic repair of coracoclavicular ligaments with a double system (double tunnel in the clavicle and in the coracoid) permits vertical translation that is more like that of the acromioclavicular joint. Acromioclavicular repair in a "V" configuration does not seem to be biomechanically sufficient.

  10. Adhesive-Bonded Composite Joint Analysis with Delaminated Surface Ply Using Strain-Energy Release Rate (United States)

    Chadegani, Alireza; Yang, Chihdar; Smeltzer, Stanley S. III


    This paper presents an analytical model to determine the strain energy release rate due to an interlaminar crack of the surface ply in adhesively bonded composite joints subjected to axial tension. Single-lap shear-joint standard test specimen geometry with thick bondline is followed for model development. The field equations are formulated by using the first-order shear-deformation theory in laminated plates together with kinematics relations and force equilibrium conditions. The stress distributions for the adherends and adhesive are determined after the appropriate boundary and loading conditions are applied and the equations for the field displacements are solved. The system of second-order differential equations is solved to using the symbolic computation tool Maple 9.52 to provide displacements fields. The equivalent forces at the tip of the prescribed interlaminar crack are obtained based on interlaminar stress distributions. The strain energy release rate of the crack is then determined by using the crack closure method. Finite element analyses using the J integral as well as the crack closure method are performed to verify the developed analytical model. It has been shown that the results using the analytical method correlate well with the results from the finite element analyses. An attempt is made to predict the failure loads of the joints based on limited test data from the literature. The effectiveness of the inclusion of bondline thickness is justified when compared with the results obtained from the previous model in which a thin bondline and uniform adhesive stresses through the bondline thickness are assumed.

  11. A complexity science-based framework for global joint operations analysis to support force projection: LDRD Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, Craig R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). System Sustainment & Readiness Technologies Dept.


    The military is undergoing a significant transformation as it modernizes for the information age and adapts to address an emerging asymmetric threat beyond traditional cold war era adversaries. Techniques such as traditional large-scale, joint services war gaming analysis are no longer adequate to support program evaluation activities and mission planning analysis at the enterprise level because the operating environment is evolving too quickly. New analytical capabilities are necessary to address modernization of the Department of Defense (DoD) enterprise. This presents significant opportunity to Sandia in supporting the nation at this transformational enterprise scale. Although Sandia has significant experience with engineering system of systems (SoS) and Complex Adaptive System of Systems (CASoS), significant fundamental research is required to develop modeling, simulation and analysis capabilities at the enterprise scale. This report documents an enterprise modeling framework which will enable senior level decision makers to better understand their enterprise and required future investments.

  12. Joint Injection/Aspiration (United States)

    ... A Patient / Caregiver Treatments Joint Injection / Aspiration Joint Injections (Joint Aspirations) Fast Facts Joint aspiration is used ... is derived from a joint aspiration or joint injection? Joint aspiration usually is done for help with ...

  13. The Analysis of Electrical Energy Consumption of the Impact Screwdriver During Assembly of Fixed Threaded Joints (United States)

    Grinevich, I.; Nikishin, Vl.; Mozga, N.; Laitans, M.


    The paper deals with the possibilities of reducing the consumption of electrical energy of the impact screwdriver during the assembly of fixed threaded joints. The recommendations related to a decrease in electrical energy consumption would allow reducing product costs but so far there have been no such recommendations from the producers of the tool as to the effective operating regimes of the impact screwdrivers in relation to electrical energy consumption and necessary tightening moment of the nut. The aim of the study is to find out the economical operating mode of the electrical impact screwdriver when assembling fixed threaded joints. By varying the set speed of the rotor head and working time of the impact mechanism, there is an opportunity to determine electrical energy consumption of the tool for the given tightening moment. The results of the experiment show that at the same tightening moment obtained the electrical energy consumption of the impact screwdriver is less at a higher starting set speed of the rotor head but shorter operating time of the impact mechanism than at a lower speed of the rotor head and longer operating time of the impact mechanism.

  14. Financial Analysis of Treating Periprosthetic Joint Infections at a Tertiary Referral Center. (United States)

    Waddell, Bradford S; Briski, David C; Meyer, Mark S; Ochsner, John L; Chimento, George F


    Periprosthetic joint infection (PJI) is a significant challenge to the orthopedic surgeon, patient, hospital, and insurance provider. Our study compares the financial information of self-originating and referral 2-stage revision hip and knee surgeries at our tertiary referral center for hip or knee PJI over the last 4 years. We performed an in-house retrospective financial review of all patients who underwent 2-stage revision hip or knee arthroplasty for infection between January 2008 and August 2013, comparing self-originating and referral cases. We found an increasing number of referrals over the study period. There was an increased cost of treating hips over knees. All scenarios generated a positive net income; however, referral hip PJIs offered lower reimbursement and net income per case (although not statistically significant), whereas knee PJIs offered higher reimbursement and net income per case (although not statistically significant). With referral centers treating increased numbers of infected joints performed elsewhere, we show continued financial incentive in accepting referrals, although with less financial gain than when treating one's own hip PJI and an increased financial gain when treating referral knee PJIs. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Two implant/abutment joint designs: a comparative finite element analysis. (United States)

    Khraisat, Ameen


    The aim of this study was to compare the influence of abutment screw preload on the marginal bone stress around a conventional external-hex implant system and one with a new implant/abutment joint design. Two implant/bone models, each consisting of three parts and fabricated of titanium and bone (cortical), were built and arranged with computer-aided design software. The first model represented an external-hex implant system, while the second had a tapered extension over the external hex, 1.5 mm high, so that the apical extension of the abutment screw in the assembly did not go beyond the lower level of the implant shoulder. Meshing and generation of boundary conditions, loads, and interactions were performed for the two models. All parts were meshed independent of each other. The sole load applied on the model was a torque of 32 Ncm on the abutment screw about its axis of rotation. The first model showed deformation of the implant collar, and the resulting von Mises stress was 60 MPa in the marginal bone. In contrast, no deformation was observed in the second model. The new implant/abutment joint eliminated the deformation at the implant collar area caused by the application of tightening torque and thus eliminated the resulting stresses in the marginal bone.

  16. Analysis of the temperature field around salt diapirs

    DEFF Research Database (Denmark)

    Jensen, Peter Klint


    heat flux should be higher over 3D structures. On the other hand the areal extent of the temperature anomaly around the salt structures is less in the 3D case. Calculation examples indicate that low temperature geothermal energy exploitation of the formations around the top of a salt diapir can...

  17. genetic analysis for high temperature tolerance in bread wheat ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    selection (Reynolds et al., 1994). A number of high temperature stress-related traits have received considerable attention, in particular membrane thermostability (Saadalla et al., 1990), canopy temperature depression (Blum et al., 1982), proline content and chlorophyll content. Information on the genetic control of ...

  18. Analysis of temperature distribution in a heat conducting fiber with ...

    African Journals Online (AJOL)

    The temperature distribution in a heat conducting fiber is computed using the Galerkin Finite Element Method in the present study. The weak form of the governing differential equation is obtained and nodal temperatures for linear and quadratic interpolation functions for different mesh densities are calculated for Neumann ...

  19. Joint analysis of galaxy-galaxy lensing and galaxy clustering: Methodology and forecasts for Dark Energy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Park, Y.; Krause, E.; Dodelson, S.; Jain, B.; Amara, A.; Becker, M. R.; Bridle, S. L.; Clampitt, J.; Crocce, M.; Fosalba, P.; Gaztanaga, E.; Honscheid, K.; Rozo, E.; Sobreira, F.; Sánchez, C.; Wechsler, R. H.; Abbott, T.; Abdalla, F. B.; Allam, S.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Fausti Neto, A.; Fernandez, E.; Finley, D. A.; Flaugher, B.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; James, D. J.; Kent, S.; Kuehn, K.; Kuropatkin, N.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Melchior, P.; Miller, C. J.; Miquel, R.; Nichol, R. C.; Ogando, R.; Plazas, A. A.; Roe, N.; Romer, A. K.; Rykoff, E. S.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Vikram, V.; Walker, A. R.; Weller, J.; Zuntz, J.


    The joint analysis of galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth function of large scale structure. Our analysis will be carried out on data from the Dark Energy Survey (DES), with its measurements of both the distribution of galaxies and the tangential shears of background galaxies induced by these foreground lenses. We develop a practical approach to modeling the assumptions and systematic effects affecting small scale lensing, which provides halo masses, and large scale galaxy clustering. Introducing parameters that characterize the halo occupation distribution (HOD), photometric redshift uncertainties, and shear measurement errors, we study how external priors on different subsets of these parameters affect our growth constraints. Degeneracies within the HOD model, as well as between the HOD and the growth function, are identified as the dominant source of complication, with other systematic effects sub-dominant. The impact of HOD parameters and their degeneracies necessitate the detailed joint modeling of the galaxy sample that we employ. Finally, we conclude that DES data will provide powerful constraints on the evolution of structure growth in the universe, conservatively/optimistically constraining the growth function to 7.9%/4.8% with its first-year data that covered over 1000 square degrees, and to 3.9%/2.3% with its full five-year data that will survey 5000 square degrees, including both statistical and systematic uncertainties.

  20. Biomechanical analysis of press-extension technique on degenerative lumbar with disc herniation and staggered facet joint

    Directory of Open Access Journals (Sweden)

    Hong-gen Du


    Full Text Available This study investigates the effect of a new Chinese massage technique named “press-extension” on degenerative lumbar with disc herniation and facet joint dislocation, and provides a biomechanical explanation of this massage technique. Self-developed biomechanical software was used to establish a normal L1–S1 lumbar 3D FE model, which integrated the spine CT and MRI data-based anatomical structure. Then graphic technique is utilized to build a degenerative lumbar FE model with disc herniation and facet joint dislocation. According to the actual press-extension experiments, mechanic parameters are collected to set boundary condition for FE analysis. The result demonstrated that press-extension techniques bring the annuli fibrosi obvious induction effect, making the central nucleus pulposus forward close, increasing the pressure in front part. Study concludes that finite element modelling for lumbar spine is suitable for the analysis of press-extension technique impact on lumbar intervertebral disc biomechanics, to provide the basis for the disease mechanism of intervertebral disc herniation using press-extension technique.

  1. Analysis of global and hemispheric temperature records and prognosis (United States)

    Werner, Rolf; Valev, Dimitar; Danov, Dimitar; Guineva, Veneta; Kirillov, Andrey


    Climate changes are connected to long term variations of global and hemispheric temperatures, which are important for the work out of socio-political strategy for the near future. In the paper the annual temperature time series are modeled by linear multiple regression to identify important climate forcings including external climate factors such as atmospheric CO2 content, volcanic emissions, and the total solar irradiation as well as internal factors such as El Niño-Southern oscillation, Pacific decadal oscillation and Atlantic multidecadal oscillation. Adjusted temperatures were determined by removal of all significant influences except CO2. The adjusted temperatures follow a linear dependence toward the logarithm of the CO2 content, and the coefficient of determination is about 0.91. The evolution of the adjusted temperatures suggests that the warming due to CO2 from the beginning of the studied here time interval in 1900 has never stopped and is going on up to now. The global warming rate deduced from the adjusted temperatures since 1980 is about 0.14 ± 0.02 °C/decade. The warming rate reported in the IPCC assessment report 4 based on observed global surface temperature set is about 20% higher, due to the warming by the Atlantic multidecadal oscillation additional to the anthropogenic warming. The predicted temperature evolution based on long time changes of CO2 and the Atlantic multidecadal oscillation index shows that the Northern Hemispheric temperatures are modulated by the Atlantic multidecadal oscillation influence and will not change significantly to about 2040, after that they will increase speedily, just like during the last decades of the past century. The temperatures of the Southern Hemisphere will increase almost linearly and don't show significant periodic changes due to Atlantic multidecadal oscillation. The concrete warming rates of course are strongly depending on the future atmospheric CO2 content.

  2. Analysis on Adhesively-Bonded Joints of FRP-steel Composite Bridge under Combined Loading: Arcan Test Study and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Xu Jiang


    Full Text Available The research presented in this paper is an experimental study and numerical analysis on mechanical behavior of the adhesively-bonded joint between FRP sandwich bridge deck and steel girder. Generally, there are three typical stress states in the adhesively-bonded joint: shear stress, tensile stress, and combination of both. To realize these stress states in the adhesively-bonded joint during tests, a specific loading device is developed with the capacity of providing six different loading angles, which are 0°(pure tension, 18°, 36°, 54°, 72° and 90°(pure shear. Failure modes of adhesively-bonded joints are investigated. It indicates that, for the pure shear loading, the failure mode is the cohesive failure (near the interface between the adhesive layer and the steel support in the adhesive layer. For the pure tensile and combined loading conditions, the failure mode is the combination of fiber breaking, FRP delamination and interfacial adhesion failure between the FRP sandwich deck and the adhesive layer. The load-bearing capacities of adhesive joints under combined loading are much lower than those of the pure tensile and pure shear loading conditions. According to the test results of six angle loading conditions, a tensile/shear failure criterion of the adhesively-bonded joint is obtained. By using Finite Element (FE modeling method, linear elastic simulations are performed to characterize the stress distribution throughout the adhesively-bonded joint.

  3. Effects of denervation of the hip joint on results of clinical observations and instrumented gait analysis in dogs with sodium urate crystal-induced synovitis. (United States)

    Hassan, Elham A; Lambrechts, Nicolaas E; Weng, Hsin-Yi; Snyder, Paul W; Breur, Gert J


    OBJECTIVE To evaluate the effects of selective hip joint denervation on gait abnormalities and signs of hip joint pain in dogs. ANIMALS 6 healthy adult hound-type dogs. PROCEDURES Minimally invasive denervation was performed on the right hip joint of each dog. Two weeks later, sodium urate was injected into the right hip joint to induce synovitis. Dogs were evaluated clinically and by use of instrumented gait analysis before and 2 weeks after minimally invasive denervation and 4, 8, and 24 hours after induction of synovitis. Dogs were euthanized, and necropsy and histologic examination were performed. RESULTS No kinetic or kinematic gait modifications were detected 2 weeks after minimally invasive denervation. Denervation did not eliminate signs of pain and lameness associated with sodium urate-induced synovitis. Results of histologic examination confirmed that denervation was an effective method for transecting the innervation of the craniolateral and caudolateral aspects of the hip joint capsule. CONCLUSIONS AND CLINICAL RELEVANCE In this study, minimally invasive denervation did not result in gait modifications in dogs. Denervation did not abolish the signs of pain and lameness associated with generalized induced synovitis of the hip joint. Further studies are required before conclusions can be drawn regarding the clinical usefulness of hip joint denervation for dogs with hip dysplasia.

  4. Performance analysis of PV panel under varying surface temperature

    Directory of Open Access Journals (Sweden)

    Kumar Tripathi Abhishek


    Full Text Available The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1°C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1°C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/°C.

  5. Turbine blade temperature calculation and life estimation - a sensitivity analysis

    Directory of Open Access Journals (Sweden)

    Majid Rezazadeh Reyhani


    Full Text Available The overall operating cost of the modern gas turbines is greatly influenced by the durability of hot section components operating at high temperatures. In turbine operating conditions, some defects may occur which can decrease hot section life. In the present paper, methods used for calculating blade temperature and life are demonstrated and validated. Using these methods, a set of sensitivity analyses on the parameters affecting temperature and life of a high pressure, high temperature turbine first stage blade is carried out. Investigated uncertainties are: (1 blade coating thickness, (2 coolant inlet pressure and temperature (as a result of secondary air system, and (3 gas turbine load variation. Results show that increasing thermal barrier coating thickness by 3 times, leads to rise in the blade life by 9 times. In addition, considering inlet cooling temperature and pressure, deviation in temperature has greater effect on blade life. One of the interesting points that can be realized from the results is that 300 hours operation at 70% load can be equal to one hour operation at base load.

  6. Experimental analysis of temperature profiles in ceramic brickwork elements subjected to high temperatures

    Directory of Open Access Journals (Sweden)

    Maciá, M. E.


    Full Text Available This article discusses heat transfer through a brick element in order to know the thermal behavior of onedimensional brickwork masonry samples exposed to high temperatures. The object of the tests is to build time-temperature curves according to different thermal steps in transient to experimentally determine the temperature profiles in the interior of a wall. Through this study, it is possible to demonstrate absolute moisture of a factory item from 300 °C (variation of temperatures in the interior of the element, avoid the associated phenomenon of evaporation of water during the thermal process as well as to obtain profiles of temperatures that help calculate the cross section of a factory element subjected to high temperatures.En este artículo se analiza la transferencia de calor a través de un elemento de fábrica de ladrillo con el fin de conocer el comportamiento térmico de secciones de fábrica unidimensionales expuestas a altas temperaturas. El objeto de los ensayos es construir curvas tiempo-temperatura en función de diversos escalones térmicos en régimen transitorio para determinar experimentalmente los perfiles de temperatura en el interior de un muro. A través de este estudio es posible evidenciar el contenido de humedad absoluta de un elemento de fábrica a partir de los 300 ºC (variación de las temperaturas en el interior del elemento, evitar el fenómeno asociado de la evaporación del agua durante el proceso térmico así como obtener perfiles de temperaturas que ayuden a calcular la sección eficaz de un elemento de fábrica sometido a altas temperaturas.

  7. Analysis of the high-temperature particulate collection problem

    Energy Technology Data Exchange (ETDEWEB)

    Razgaitis, R.


    Particulate agglomeration and separation at high temperatures and pressures are examined, with particular emphasis on the unique features of the direct-cycle application of fluidized-bed combustion. The basic long-range mechanisms of aerosol separation are examined, and the effects of high temperature and high pressure on usable collection techniques are assessed. Primary emphasis is placed on those avenues that are not currently attracting widespread research. The high-temperature, particulate-collection problem is surveyed, together with the peculiar requirements associated with operation of turbines with particulate-bearing gas streams. 238 references.

  8. Measurement and Analysis of the Diffusible Hydrogen in Underwater Wet Welding Joint

    Directory of Open Access Journals (Sweden)

    Kong Xiangfeng


    Full Text Available The diffusible hydrogen in steel weldments is one of the main reasons that led to hydrogen assisted cracking. In this paper, the results of literatures survey and preliminary tests of the diffusible hydrogen in underwater wet welding joint were presented. A fluid-discharge method of for measuring the diffusible hydrogen in weldment was introduced in detail. Two kinds of underwater welding electrode diffusible hydrogen are 26.5 mL/100g and 35.5 mL/100g by fluid-discharge method, which are high levels. The diffusible hydrogen of underwater welding is higher than atmospheric welding, and the result is closely related to welding material. The best way to control the diffusible hydrogen is adjusting welding material and improving fluidity of slag.

  9. Effects of several temporomandibular disorders on the stress distributions of temporomandibular joint: a finite element analysis. (United States)

    Liu, Zhan; Qian, Yingli; Zhang, Yuanli; Fan, Yubo


    The aim of this study was to evaluate stress distributions in the temporomandibular joints (TMJs) with temporomandibular disorders (TMDs) for comparison with healthy TMJs. A model of mandible and normal TMJs was developed according to CT images. The interfaces between the discs and the articular cartilages were treated as contact elements. Nonlinear cable elements were used to simulate disc attachments. Based on this model, seven models of various TMDs were established. The maximum stresses of the discs with anterior, posterior, medial and lateral disc displacement (ADD, PDD, MDD and LDD) were 12.09, 9.33, 10.71 and 6.07 times magnitude of the identically normal disc, respectively. The maximum stresses of the posterior articular eminences in ADD, PDD, MDD, LDD, relaxation of posterior attachments and disc perforation models were 21, 59, 46, 21, 13 and 15 times greater than the normal model, respectively. TMDs could cause increased stresses in the discs and posterior articular eminences.

  10. A Game Theoretical Analysis about Joint-Rebate in Platform-based Retailing Systems

    DEFF Research Database (Denmark)

    Li, Hongyan Jenny


    . The seller pays rent and also a percentage of his revenue to the platform as commissions for using the facility and services of the platform. In a promotion program, both the retail platform and the seller have strategic options of either oering rebates individually or launching a joint rebate. The rebate......Rebates are commonly used as one of the most important short-term promotion tactics in retailing industries. In this paper, we study a platform-based retail system consisting of a retail platform who provides a retail facility and a product seller who sells products through the retail platform...... amount is voluntary and therefore endogenous decisions in our model. We investigate the optimal rebate strategies and performance of each party in the retail system analytically. Research results show that, given an exogenous retail price and a commission rate, the platform and the seller may choose...

  11. Joint analysis of stochastic processes with application to smoking patterns and insomnia. (United States)

    Luo, Sheng


    This article proposes a joint modeling framework for longitudinal insomnia measurements and a stochastic smoking cessation process in the presence of a latent permanent quitting state (i.e., 'cure'). We use a generalized linear mixed-effects model and a stochastic mixed-effects model for the longitudinal measurements of insomnia symptom and for the smoking cessation process, respectively. We link these two models together via the latent random effects. We develop a Bayesian framework and Markov Chain Monte Carlo algorithm to obtain the parameter estimates. We formulate and compute the likelihood functions involving time-dependent covariates. We explore the within-subject correlation between insomnia and smoking processes. We apply the proposed methodology to simulation studies and the motivating dataset, that is, the Alpha-Tocopherol, Beta-Carotene Lung Cancer Prevention study, a large longitudinal cohort study of smokers from Finland. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Neglected chaos in international stock markets: Bayesian analysis of the joint return-volatility dynamical system (United States)

    Tsionas, Mike G.; Michaelides, Panayotis G.


    We use a novel Bayesian inference procedure for the Lyapunov exponent in the dynamical system of returns and their unobserved volatility. In the dynamical system, computation of largest Lyapunov exponent by traditional methods is impossible as the stochastic nature has to be taken explicitly into account due to unobserved volatility. We apply the new techniques to daily stock return data for a group of six countries, namely USA, UK, Switzerland, Netherlands, Germany and France, from 2003 to 2014, by means of Sequential Monte Carlo for Bayesian inference. The evidence points to the direction that there is indeed noisy chaos both before and after the recent financial crisis. However, when a much simpler model is examined where the interaction between returns and volatility is not taken into consideration jointly, the hypothesis of chaotic dynamics does not receive much support by the data ("neglected chaos").

  13. Joint Analysis of X-Ray and Sunyaev-Zel'Dovich Observations of Galaxy Clusters Using an Analytic Model of the Intracluster Medium (United States)

    Hasler, Nicole; Bulbul, Esra; Bonamente, Massimiliano; Carlstrom, John E.; Culverhouse, Thomas L.; Gralla, Megan; Greer, Christopher; Lamb, James W.; Hawkins, David; Hennessy, Ryan; hide


    We perform a joint analysis of X-ray and Sunyaev-Zel'dovich effect data using an analytic model that describes the gas properties of galaxy clusters. The joint analysis allows the measurement of the cluster gas mass fraction profile and Hubble constant independent of cosmological parameters. Weak cosmological priors are used to calculate the overdensity radius within which the gas mass fractions are reported. Such an analysis can provide direct constraints on the evolution of the cluster gas mass fraction with redshift. We validate the model and the joint analysis on high signal-to-noise data from the Chandra X-ray Observatory and the Sunyaev-Zel'dovich Array for two clusters, A2631 and A2204.

  14. Hardness analysis of welded joints of austenitic and duplex stainless steels (United States)

    Topolska, S.


    Stainless steels are widely used in the modern world. The continuous increase in the use of stainless steels is caused by getting greater requirements relating the corrosion resistance of all types of devices. The main property of these steels is the ability to overlap a passive layer of an oxide on their surface. This layer causes that they become resistant to oxidation. One of types of corrosion-resistant steels is ferritic-austenitic steel of the duplex type, which has good strength properties. It is easily formable and weldable as well as resistant to erosion and abrasive wear. It has a low susceptibility to stress-corrosion cracking, to stress corrosion, to intercrystalline one, to pitting one and to crevice one. For these reasons they are used, among others, in the construction of devices and facilities designed for chemicals transportation and for petroleum and natural gas extraction. The paper presents the results which shows that the particular specimens of the ][joint representing both heat affected zones (from the side of the 2205 steel and the 316L one) and the weld are characterized by higher hardness values than in the case of the same specimens for the 2Y joint. Probably this is caused by machining of edges of the sections of metal sheets before the welding process, which came to better mixing of native materials and the filler metal. After submerged arc welding the 2205 steel still retains the diphase, austenitic-ferritic structure and the 316L steel retains the austenitic structure with sparse bands of ferrite σ.

  15. Glenohumeral joint motion after subscapularis tendon repair: an analysis of cadaver shoulder models. (United States)

    Sano, Teiichi; Aoki, Mitsuhiro; Tanaka, Yoshitaka; Izumi, Tomoki; Fujimiya, Mineko; Yamashita, Toshihiko


    As for the surgical treatment of the rotator cuff tears, the subscapularis tendon tears have recently received much attention for the mini-open or arthroscopic repair. The results of surgical repair for the subscapularis tendon tear are satisfactory, but the range of external rotation is reported to be restricted after the repair. The purpose of this study was to evaluate the range of glenohumeral joint motion after repairs of various sizes of subscapularis tendon tears. Using eight fresh frozen human cadaveric shoulders (mean age at death, 81.5 years), three sizes of subscapularis tendon tear (small, medium, and large) were made and then repaired. With the scapula fixed to the wooden jig, the end-range of glenohumeral motion was measured with passive movement applied through 1.0-Nm torque in the directions of scapular elevation, flexion, abduction, extension, horizontal abduction, and horizontal adduction. The passive end-ranges of external and internal rotation in various positions with rotational torque of 1.0 Nm were also measured. Differences in the ranges among the three type tears were analyzed. As tear size increased, range of glenohumeral motion in horizontal abduction after repair decreased gradually and was significantly decreased with the large size tear (P size in every glenohumeral position. The prominent decrease in external rotation (around 40° reduction from intact shoulders) was observed in shoulders after repair of large size tear at 30° to 60° of scapular elevation and abduction. As the size of the subscapularis tendon tear increased, the passive ranges of horizontal abduction and external rotation of the glenohumeral joint after repair decreased significantly. In shoulders with a subscapularis tendon tear, it is necessary to consider the reduction of external rotation depending on tear size.

  16. On the microstructure analysis of FSW joints of aluminium components made via direct metal laser sintering (United States)

    Scherillo, Fabio; Astarita, Antonello; di Martino, Daniela; Contaldi, Vincenzo; di Matteo, Luca; di Petta, Paolo; Casarin, Renzo; Squillace, Antonino; Langella, Antonio


    Additive Manufacturing (AM), applied to metal industry, is a family of processes that allow complex shape components to be realized from raw materials in the form of powders. The compaction of the powders can be achieved by local melting of the powder bed or by solid state sintering. Direct Metal Laser Sintering (DMLS) is an additive manufacturing process in which a focalized laser beam is the heat source that allows the powders to be compacted. By DMLS it is possible to realize complex shape components. One of the limits of DMLS, as for every additive layer manufacturing techniques, is the unfeasibility to realize large dimension parts. Due to this limit the study of joining process of parts made via ALM is of great interest. One of the most promising options is the Friction Stir Welding (FSW), a solid state welding technique that has been proven to be very effective in the welding of metals difficult to weld, above all aluminium alloys. Since FSW is a solid-state technique, the microstructure of the various zone of the weld bead depends not only by the process itself but also by the parent microstruct ure of the parts to be welded. Furthermore, parts made of aluminium alloy via DMLS have a particular microstructure that is the result of repeated severe thermal cycles. In the present work the authors, starting from the description of the parent microstructure of parts made of AlSi10Mg aluminium alloy, study the microstructure evolution occurred within the joint made by Friction Stir Welding, analysing in details the microstructure of the main well recognized zone of the weld bead. The structure of the parent material is characterized by the presence of melting pools with a very fine microstructure. In the joint the recrystallization, the grain refinement and, above all, the redistribution of intermetallic phases occurs, resulting in an homogenization of the microstructure and in an increase of micro hardness.

  17. Energy and exergy analysis of low temperature district heating network

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend


    Low temperature district heating with reduced network supply and return temperature provides better match of the low quality building heating demand and the low quality heating supply from waste heat or renewable energy. In this paper, a hypothetical low temperature district heating network...... is designed to supply heating for 30 low energy detached residential houses. The network operational supply/return temperature is set as 55 °C/25 °C, which is in line with a pilot project carried out in Denmark. Two types of in-house substations are analyzed to supply the consumer domestic hot water demand...... optimization procedure and the network simultaneous factor. Through the simulation, the overall system energy and exergy efficiencies are calculated and the exergy losses for the major district heating system components are identified. Based on the results, suggestions are given to further reduce the system...

  18. Computational analysis of frp composite under different temperature gradient (United States)

    Gunasekar, P.; Manigandan, S.


    Composite material strength depends on the stiffness of fiber and the resin which is used for reinforcement. The strength of the laminate can be increased by applying good manufacturing practices. The strength is directly depending on the property of resin. The property of the any compound subjected to changed when they exposed to the temperature. This paper investigates the strength of laminate when they subjected to different temperature gradient of resin while manufacturing. The resin is preheated before adding hardener with them. These types of laminate reinforced with resin at different levels of temperature 20c, 40c, and 60c. These different temperature resin are used for reinforcement and the specimen tested. The comparative results are made to find how the stiffness of laminate changes with respect to the thermal property of resin. The results are helpful to obtain high strength laminate.

  19. Spatial and Temporal Analysis of Bias HAST System Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Kent B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Furrer, III, Clint T [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sandoval, Paul Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garrett, Stephen E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pfeifer, Nathaniel Bryant [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    High-reliability components for high-consequence systems require detailed testing of operation after having undergone highly accelerated stress testing (HAST) under unusual conditions of high-temperature and humidity. This paper describes the design and operation of a system called "Wormwood" that is a highly multiplexed temperature measurement system that is designed to operate under HAST conditions to allow measurement of the temperature as a function of time and position in a HAST chamber. HAST chambers have single-point temperature measurements that can be traceable to NIST standards. The objective of these "Wormwood" measurements is to verify the uniformity and stability of the remaining volume of the HAST chamber with respect to the single traceable standard.

  20. Concurrent validity and reliability of two-dimensional video analysis of hip and knee joint motion during mechanical lifting. (United States)

    Norris, Beth S; Olson, Sharon L


    Movement patterns used during mechanical lifting are usually assessed subjectively by clinicians as a stoop or squat based on visual estimation of joint motion and position. Two-dimensional (2D) video analysis has the potential to objectively measure joint motion during a mechanical lifting task. This study investigated concurrent validity, intrarater, interrater, and test-retest reliability of 2D video analysis using Dartfish software for the measurement of sagittal plane angles at the hip and knee during mechanical lifting. Fifteen healthy female participants (mean age 27.1 ± 7.1 years) were recruited to perform mechanical lifting on 2 separate test days. Concurrent validity was determined by comparing 2D derived hip and knee flexion angles to goniometric measures. Intrarater and interrater reliability of the 2D kinematic procedures was determined by using examiners with varying experience in the use of Dartfish software. Between-day test-retest reliability of hip and knee 2D kinematics during mechanical lifting was assessed. Concurrent validity of 2D angle analysis using Dartfish software was supported by high correlations (Pearson r ≥ 0.95) and nonsignificant differences between 2D and goniometric measures of sagittal plane hip and knee motion. Both intrarater and interrater reliability values of hip and knee flexion angles were excellent (ICC ≥ 0.91). ICCs for test-retest reliability were 0.79 and 0.91 for hip and knee flexion, respectively. These findings and the ease of data capture using this system provide support for the clinical utility of 2D video analysis to provide objective measures of movement patterns at the hip and knee during a dynamic functional task.