Science.gov

Sample records for process parameter development

  1. Process Damping Parameters

    NASA Astrophysics Data System (ADS)

    Turner, Sam

    2011-12-01

    The phenomenon of process damping as a stabilising effect in milling has been encountered by machinists since milling and turning began. It is of great importance when milling aerospace alloys where maximum surface speed is limited by excessive tool wear and high speed stability lobes cannot be attained. Much of the established research into regenerative chatter and chatter avoidance has focussed on stability lobe theory with different analytical and time domain models developed to expand on the theory first developed by Trusty and Tobias. Process damping is a stabilising effect that occurs when the surface speed is low relative to the dominant natural frequency of the system and has been less successfully modelled and understood. Process damping is believed to be influenced by the interference of the relief face of the cutting tool with the waveform traced on the cut surface, with material properties and the relief geometry of the tool believed to be key factors governing performance. This study combines experimental trials with Finite Element (FE) simulation in an attempt to identify and understand the key factors influencing process damping performance in titanium milling. Rake angle, relief angle and chip thickness are the variables considered experimentally with the FE study looking at average radial and tangential forces and surface compressive stress. For the experimental study a technique is developed to identify the critical process damping wavelength as a means of measuring process damping performance. For the range of parameters studied, chip thickness is found to be the dominant factor with maximum stable parameters increased by a factor of 17 in the best case. Within the range studied, relief angle was found to have a lesser effect than expected whilst rake angle had an influence.

  2. Development of optimization model for sputtering process parameter based on gravitational search algorithm

    NASA Astrophysics Data System (ADS)

    Norlina, M. S.; Diyana, M. S. Nor; Mazidah, P.; Rusop, M.

    2016-07-01

    In the RF magnetron sputtering process, the desirable layer properties are largely influenced by the process parameters and conditions. If the quality of the thin film has not reached up to its intended level, the experiments have to be repeated until the desirable quality has been met. This research is proposing Gravitational Search Algorithm (GSA) as the optimization model to reduce the time and cost to be spent in the thin film fabrication. The optimization model's engine has been developed using Java. The model is developed based on GSA concept, which is inspired by the Newtonian laws of gravity and motion. In this research, the model is expected to optimize four deposition parameters which are RF power, deposition time, oxygen flow rate and substrate temperature. The results have turned out to be promising and it could be concluded that the performance of the model is satisfying in this parameter optimization problem. Future work could compare GSA with other nature based algorithms and test them with various set of data.

  3. Development of process parameters for 22 nm PMOS using 2-D analytical modeling

    SciTech Connect

    Maheran, A. H. Afifah; Menon, P. S.; Shaari, S.; Ahmad, I.; Faizah, Z. A. Noor

    2015-04-24

    The complementary metal-oxide-semiconductor field effect transistor (CMOSFET) has become major challenge to scaling and integration. Innovation in transistor structures and integration of novel materials are necessary to sustain this performance trend. CMOS variability in the scaling technology becoming very important concern due to limitation of process control; over statistically variability related to the fundamental discreteness and materials. Minimizing the transistor variation through technology optimization and ensuring robust product functionality and performance is the major issue.In this article, the continuation study on process parameters variations is extended and delivered thoroughly in order to achieve a minimum leakage current (I{sub LEAK}) on PMOS planar transistor at 22 nm gate length. Several device parameters are varies significantly using Taguchi method to predict the optimum combination of process parameters fabrication. A combination of high permittivity material (high-k) and metal gate are utilized accordingly as gate structure where the materials include titanium dioxide (TiO{sub 2}) and tungsten silicide (WSi{sub x}). Then the L9 of the Taguchi Orthogonal array is used to analyze the device simulation where the results of signal-to-noise ratio (SNR) of Smaller-the-Better (STB) scheme are studied through the percentage influences of the process parameters. This is to achieve a minimum I{sub LEAK} where the maximum predicted I{sub LEAK} value by International Technology Roadmap for Semiconductors (ITRS) 2011 is said to should not above 100 nA/µm. Final results shows that the compensation implantation dose acts as the dominant factor with 68.49% contribution in lowering the device’s leakage current. The absolute process parameters combination results in I{sub LEAK} mean value of 3.96821 nA/µm where is far lower than the predicted value.

  4. Development of process parameters for 22 nm PMOS using 2-D analytical modeling

    NASA Astrophysics Data System (ADS)

    Maheran, A. H. Afifah; Menon, P. S.; Ahmad, I.; Shaari, S.; Faizah, Z. A. Noor

    2015-04-01

    The complementary metal-oxide-semiconductor field effect transistor (CMOSFET) has become major challenge to scaling and integration. Innovation in transistor structures and integration of novel materials are necessary to sustain this performance trend. CMOS variability in the scaling technology becoming very important concern due to limitation of process control; over statistically variability related to the fundamental discreteness and materials. Minimizing the transistor variation through technology optimization and ensuring robust product functionality and performance is the major issue.In this article, the continuation study on process parameters variations is extended and delivered thoroughly in order to achieve a minimum leakage current (ILEAK) on PMOS planar transistor at 22 nm gate length. Several device parameters are varies significantly using Taguchi method to predict the optimum combination of process parameters fabrication. A combination of high permittivity material (high-k) and metal gate are utilized accordingly as gate structure where the materials include titanium dioxide (TiO2) and tungsten silicide (WSix). Then the L9 of the Taguchi Orthogonal array is used to analyze the device simulation where the results of signal-to-noise ratio (SNR) of Smaller-the-Better (STB) scheme are studied through the percentage influences of the process parameters. This is to achieve a minimum ILEAK where the maximum predicted ILEAK value by International Technology Roadmap for Semiconductors (ITRS) 2011 is said to should not above 100 nA/µm. Final results shows that the compensation implantation dose acts as the dominant factor with 68.49% contribution in lowering the device's leakage current. The absolute process parameters combination results in ILEAK mean value of 3.96821 nA/µm where is far lower than the predicted value.

  5. Attitude determination of a high altitude balloon system. Part 2: Development of the parameter determination process

    NASA Technical Reports Server (NTRS)

    Nigro, N. J.; Elkouh, A. F.

    1975-01-01

    The attitude of the balloon system is determined as a function of time if: (a) a method for simulating the motion of the system is available, and (b) the initial state is known. The initial state is obtained by fitting the system motion (as measured by sensors) to the corresponding output predicted by the mathematical model. In the case of the LACATE experiment the sensors consisted of three orthogonally oriented rate gyros and a magnetometer all mounted on the research platform. The initial state was obtained by fitting the angular velocity components measured with the gyros to the corresponding values obtained from the solution of the math model. A block diagram illustrating the attitude determination process employed for the LACATE experiment is shown. The process consists of three essential parts; a process for simulating the balloon system, an instrumentation system for measuring the output, and a parameter estimation process for systematically and efficiently solving the initial state. Results are presented and discussed.

  6. Optimization of processing parameters and ingredients for development of low-fat fibre-supplemented paneer.

    PubMed

    Singh, G; Kumar, A; Kumbhar, B K; Dar, B N

    2015-02-01

    Increasing demand of low calorie and high fibre containing products give impetus to dairy industry for development of a well palatable low calorie dairy products like paneer. The objective of the present study was to develop low-fat fibre-supplemented paneer. The ingredients were chosen for low-fat fibre- supplemented paneer to reduce the cost and calorie content besides providing the functional benefits. Optimization of ingredients was carried out in terms of independent variables viz wheat bran (0.4-0.8 %), maltodextrin (1-5 %), coagulation temperature (60-80 °C) and amount of citric acid solution (150-210 ml). Response Surface Methodology (RSM) was used to design the experiments and to select the optimum levels of ingredients. Paneer was made by using different levels of ingredients by coagulating hot milk using citric acid solution followed by pressing and dipping in chilled water for texturization. These parameters were evaluated in terms of physico-chemical parameters viz water activity, pH and acidity. Instrumental texture profile analysis (TPA) of paneer during optimization trials was done using TAXT 2i Texture Analyzer. The textural responses namely hardness, adhesiveness, springiness, cohesiveness, gumminess and chewiness were measured via Texture Analyzer. The sensory properties namely flavor, appearance, body and texture, mouth feel and overall acceptability of paneer samples were evaluated by a semi-trained panel of judges using 9-point hedonic scale. Full second order polynomial was developed to predict each response. All the textural and sensory responses were statistically analysed. PMID:25694679

  7. Development of Processing Parameters for Organic Binders Using Selective Laser Sintering

    NASA Technical Reports Server (NTRS)

    Mobasher, Amir A.

    2003-01-01

    This document describes rapid prototyping, its relation to Computer Aided Design (CAD), and the application of these techniques to choosing parameters for Selective Laser Sintering (SLS). The document reviews the parameters selected by its author for his project, the SLS machine used, and its software.

  8. Development of an ideal observer that incorporates nuisance parameters and processes list-mode data.

    PubMed

    MacGahan, Christopher J; Kupinski, Matthew A; Hilton, Nathan R; Brubaker, Erik M; Johnson, William C

    2016-04-01

    Observer models were developed to process data in list-mode format in order to perform binary discrimination tasks for use in an arms-control-treaty context. Data used in this study was generated using GEANT4 Monte Carlo simulations for photons using custom models of plutonium inspection objects and a radiation imaging system. Observer model performance was evaluated and presented using the area under the receiver operating characteristic curve. The ideal observer was studied under both signal-known-exactly conditions and in the presence of unknowns such as object orientation and absolute count-rate variability; when these additional sources of randomness were present, their incorporation into the observer yielded superior performance. PMID:27140781

  9. Development of an ideal observer that incorporates nuisance parameters and processes list-mode data

    DOE PAGESBeta

    MacGahan, Christopher Jonathan; Kupinski, Matthew Alan; Hilton, Nathan R.; Brubaker, Erik M.; Johnson, William C.

    2016-02-01

    Observer models were developed to process data in list-mode format in order to perform binary discrimination tasks for use in an arms-control-treaty context. Data used in this study was generated using GEANT4 Monte Carlo simulations for photons using custom models of plutonium inspection objects and a radiation imaging system. We evaluated observer model performance and then presented using the area under the receiver operating characteristic curve. Lastly, we studied the ideal observer under both signal-known-exactly conditions and in the presence of unknowns such as object orientation and absolute count-rate variability; when these additional sources of randomness were present, their incorporationmore » into the observer yielded superior performance.« less

  10. Application of physicochemical properties and process parameters in the development of a neural network model for prediction of tablet characteristics.

    PubMed

    Sovány, Tamás; Papós, Kitti; Kása, Péter; Ilič, Ilija; Srčič, Stane; Pintye-Hódi, Klára

    2013-06-01

    The importance of in silico modeling in the pharmaceutical industry is continuously increasing. The aim of the present study was the development of a neural network model for prediction of the postcompressional properties of scored tablets based on the application of existing data sets from our previous studies. Some important process parameters and physicochemical characteristics of the powder mixtures were used as training factors to achieve the best applicability in a wide range of possible compositions. The results demonstrated that, after some pre-processing of the factors, an appropriate prediction performance could be achieved. However, because of the poor extrapolation capacity, broadening of the training data range appears necessary. PMID:23413109

  11. Developing LBM Process Parameters for Ti-6Al-4V Thin Wall Structures and Determining the Corresponding Mechanical Characteristics

    NASA Astrophysics Data System (ADS)

    Ahuja, Bhrigu; Schaub, Adam; Karg, Michael; Lechner, Michael; Merklein, Marion; Schmidt, Michael

    The Laser Beam Melting (LBM) process technology within the family of Additive Manufacturing technology is characterized by its ability to fabricate fully dense 3D structures directly from micro-sized metal powder. With the current state of the art, Ti-6Al-4V has been processed using LBM machine systems constituting a laser with a beam diameter of about 100 μm. In order to fabricate structures with smaller wall thicknesses, processing of Ti-6Al-4V is attempted on the LBM machine system, Realizer SLM 50 consisting of a laser with a beam diameter 10 μm. The proposed paper presents the development of process parameters for fabricating fully dense Ti-6Al-4V 3D structures using the LBM machine system, Realizer SLM 50. Further experiments are carried out to determine the wall thickness and mechanical properties achievable using the selected process parameters. Analysis and scientific arguments are presented to explain the influence of building direction and heat treatment on mechanical properties.

  12. OREGON STATE UNIVERSITY (OSU) TRAINING RESEARCH ISOTOPE GENERAL ATOMICS (TRIGA) OVERPACK CLOSURE WELDING PROCESS PARAMETER DEVELOPMENT & QUALIFICATION

    SciTech Connect

    CANNELL, G.R.

    2006-09-11

    Spent Nuclear Fuel (SNF) from the Oregon State University (OSU) TRIGA{reg_sign} Reactor is currently being stored in thirteen 55-gallon drums at the Hanford Site's low-level burial grounds. This fuel is soon to be retrieved from buried storage and packaged into new containers (overpacks) for interim storage at the Hanford Interim Storage Area (ISA). One of the key activities associated with this effort is final closure of the overpack by welding. The OSU fuel is placed into an overpack, a head inserted into the overpack top, and welded closed. Weld quality, for typical welded fabrication, is established through post-weld testing and nondestructive examination (NDE); however, in this case, once the SNF is placed into the overpack, routine testing and NDE are not feasible. An alternate approach is to develop and qualify the welding process/parameters, demonstrate beforehand that they produce the desired weld quality, and then verify parameter compliance during production welding. Fluor engineers have developed a Gas Tungsten Arc Welding (GTAW) technique and parameters, demonstrating that weld quality requirements for closure of packaged SNF overpacks are met, using this alternate approach. The following reviews the activities performed for this development and qualification effort.

  13. Some matters concerned with selecting steam parameters and process-circuit solutions to optimize the parameters of steam turbine equipment and engineering design developments

    NASA Astrophysics Data System (ADS)

    Kultyshev, A. Yu.; Stepanov, M. Yu.; Polyaeva, E. N.

    2014-12-01

    The possibility and advantages of increasing steam pressure in the steam-turbine low-pressure loop for combined-cycle power plants are considered. The question about the advisability of developing and manufacturing steam turbines for being used in combined-cycle power units equipped with modern class F gas turbines for supercritical and ultrasupercritical steam parameters is raised.

  14. Development of a controlled release formulation by continuous twin screw granulation: Influence of process and formulation parameters.

    PubMed

    Vanhoorne, V; Vanbillemont, B; Vercruysse, J; De Leersnyder, F; Gomes, P; Beer, T De; Remon, J P; Vervaet, C

    2016-05-30

    The aim of this study was to evaluate the potential of twin screw granulation for the continuous production of controlled release formulations with hydroxypropylmethylcellulose as hydrophilic matrix former. Metoprolol tartrate was included in the formulation as very water soluble model drug. A premix of metoprolol tartrate, hydroxypropylmethylcellulose and filler (ratio 20/20/60, w/w) was granulated with demineralized water via twin screw granulation. After oven drying and milling, tablets were produced on a rotary Modul™ P tablet press. A D-optimal design (29 experiments) was used to assess the influence of process (screw speed, throughput, barrel temperature and screw design) and formulation parameters (starch content of the filler) on the process (torque), granule (size distribution, shape, friability, density) and tablet (hardness, friability and dissolution) critical quality attributes. The torque was dominated by the number of kneading elements and throughput, whereas screw speed and filling degree only showed a minor influence on torque. Addition of screw mixing elements after a block of kneading elements improved the yield of the process before milling as it resulted in less oversized granules and also after milling as less fines were present. Temperature was also an important parameter to optimize as a higher temperature yielded less fines and positively influenced the aspect ratio. The shape of hydroxypropylmethylcellulose granules was comparable to that of immediate release formulations. Tensile strength and friability of tablets were not dependent on the process parameters. The use of starch as filler was not beneficial with regard to granule and tablet properties. Complete drug release was obtained after 16-20h and was independent of the design's parameters. PMID:27041123

  15. Integrated water system simulation by considering hydrological and biogeochemical processes: model development, with parameter sensitivity and autocalibration

    NASA Astrophysics Data System (ADS)

    Zhang, Y. Y.; Shao, Q. X.; Ye, A. Z.; Xing, H. T.; Xia, J.

    2016-02-01

    Integrated water system modeling is a feasible approach to understanding severe water crises in the world and promoting the implementation of integrated river basin management. In this study, a classic hydrological model (the time variant gain model: TVGM) was extended to an integrated water system model by coupling multiple water-related processes in hydrology, biogeochemistry, water quality, and ecology, and considering the interference of human activities. A parameter analysis tool, which included sensitivity analysis, autocalibration and model performance evaluation, was developed to improve modeling efficiency. To demonstrate the model performances, the Shaying River catchment, which is the largest highly regulated and heavily polluted tributary of the Huai River basin in China, was selected as the case study area. The model performances were evaluated on the key water-related components including runoff, water quality, diffuse pollution load (or nonpoint sources) and crop yield. Results showed that our proposed model simulated most components reasonably well. The simulated daily runoff at most regulated and less-regulated stations matched well with the observations. The average correlation coefficient and Nash-Sutcliffe efficiency were 0.85 and 0.70, respectively. Both the simulated low and high flows at most stations were improved when the dam regulation was considered. The daily ammonium-nitrogen (NH4-N) concentration was also well captured with the average correlation coefficient of 0.67. Furthermore, the diffuse source load of NH4-N and the corn yield were reasonably simulated at the administrative region scale. This integrated water system model is expected to improve the simulation performances with extension to more model functionalities, and to provide a scientific basis for the implementation in integrated river basin managements.

  16. Additive Manufacturing of Single-Crystal Superalloy CMSX-4 Through Scanning Laser Epitaxy: Computational Modeling, Experimental Process Development, and Process Parameter Optimization

    NASA Astrophysics Data System (ADS)

    Basak, Amrita; Acharya, Ranadip; Das, Suman

    2016-06-01

    This paper focuses on additive manufacturing (AM) of single-crystal (SX) nickel-based superalloy CMSX-4 through scanning laser epitaxy (SLE). SLE, a powder bed fusion-based AM process was explored for the purpose of producing crack-free, dense deposits of CMSX-4 on top of similar chemistry investment-cast substrates. Optical microscopy and scanning electron microscopy (SEM) investigations revealed the presence of dendritic microstructures that consisted of fine γ' precipitates within the γ matrix in the deposit region. Computational fluid dynamics (CFD)-based process modeling, statistical design of experiments (DoE), and microstructural characterization techniques were combined to produce metallurgically bonded single-crystal deposits of more than 500 μm height in a single pass along the entire length of the substrate. A customized quantitative metallography based image analysis technique was employed for automatic extraction of various deposit quality metrics from the digital cross-sectional micrographs. The processing parameters were varied, and optimal processing windows were identified to obtain good quality deposits. The results reported here represent one of the few successes obtained in producing single-crystal epitaxial deposits through a powder bed fusion-based metal AM process and thus demonstrate the potential of SLE to repair and manufacture single-crystal hot section components of gas turbine systems from nickel-based superalloy powders.

  17. Additive Manufacturing of Single-Crystal Superalloy CMSX-4 Through Scanning Laser Epitaxy: Computational Modeling, Experimental Process Development, and Process Parameter Optimization

    NASA Astrophysics Data System (ADS)

    Basak, Amrita; Acharya, Ranadip; Das, Suman

    2016-08-01

    This paper focuses on additive manufacturing (AM) of single-crystal (SX) nickel-based superalloy CMSX-4 through scanning laser epitaxy (SLE). SLE, a powder bed fusion-based AM process was explored for the purpose of producing crack-free, dense deposits of CMSX-4 on top of similar chemistry investment-cast substrates. Optical microscopy and scanning electron microscopy (SEM) investigations revealed the presence of dendritic microstructures that consisted of fine γ' precipitates within the γ matrix in the deposit region. Computational fluid dynamics (CFD)-based process modeling, statistical design of experiments (DoE), and microstructural characterization techniques were combined to produce metallurgically bonded single-crystal deposits of more than 500 μm height in a single pass along the entire length of the substrate. A customized quantitative metallography based image analysis technique was employed for automatic extraction of various deposit quality metrics from the digital cross-sectional micrographs. The processing parameters were varied, and optimal processing windows were identified to obtain good quality deposits. The results reported here represent one of the few successes obtained in producing single-crystal epitaxial deposits through a powder bed fusion-based metal AM process and thus demonstrate the potential of SLE to repair and manufacture single-crystal hot section components of gas turbine systems from nickel-based superalloy powders.

  18. Development of a new version of the Liverpool Malaria Model. I. Refining the parameter settings and mathematical formulation of basic processes based on a literature review

    PubMed Central

    2011-01-01

    Background A warm and humid climate triggers several water-associated diseases such as malaria. Climate- or weather-driven malaria models, therefore, allow for a better understanding of malaria transmission dynamics. The Liverpool Malaria Model (LMM) is a mathematical-biological model of malaria parasite dynamics using daily temperature and precipitation data. In this study, the parameter settings of the LMM are refined and a new mathematical formulation of key processes related to the growth and size of the vector population are developed. Methods One of the most comprehensive studies to date in terms of gathering entomological and parasitological information from the literature was undertaken for the development of a new version of an existing malaria model. The knowledge was needed to allow the justification of new settings of various model parameters and motivated changes of the mathematical formulation of the LMM. Results The first part of the present study developed an improved set of parameter settings and mathematical formulation of the LMM. Important modules of the original LMM version were enhanced in order to achieve a higher biological and physical accuracy. The oviposition as well as the survival of immature mosquitoes were adjusted to field conditions via the application of a fuzzy distribution model. Key model parameters, including the mature age of mosquitoes, the survival probability of adult mosquitoes, the human blood index, the mosquito-to-human (human-to-mosquito) transmission efficiency, the human infectious age, the recovery rate, as well as the gametocyte prevalence, were reassessed by means of entomological and parasitological observations. This paper also revealed that various malaria variables lack information from field studies to be set properly in a malaria modelling approach. Conclusions Due to the multitude of model parameters and the uncertainty involved in the setting of parameters, an extensive literature survey was carried out

  19. A high-throughput 2D-analytical technique to obtain single protein parameters from complex cell lysates for in silico process development of ion exchange chromatography.

    PubMed

    Kröner, Frieder; Elsäßer, Dennis; Hubbuch, Jürgen

    2013-11-29

    The accelerating growth of the market for biopharmaceutical proteins, the market entry of biosimilars and the growing interest in new, more complex molecules constantly pose new challenges for bioseparation process development. In the presented work we demonstrate the application of a multidimensional, analytical separation approach to obtain the relevant physicochemical parameters of single proteins in a complex mixture for in silico chromatographic process development. A complete cell lysate containing a low titre target protein was first fractionated by multiple linear salt gradient anion exchange chromatography (AEC) with varying gradient length. The collected fractions were subsequently analysed by high-throughput capillary gel electrophoresis (HT-CGE) after being desalted and concentrated. From the obtained data of the 2D-separation the retention-volumes and the concentration of the single proteins were determined. The retention-volumes of the single proteins were used to calculate the related steric-mass action model parameters. In a final evaluation experiment the received parameters were successfully applied to predict the retention behaviour of the single proteins in salt gradient AEC. PMID:24139506

  20. Development of optimum process parameters and a study of the effects of surface roughness on brazing of copper

    NASA Astrophysics Data System (ADS)

    Zaharinie, Tuan; Huda, Zainul; Izuan, Mohd Faaliq; Hamdi, Mohammed

    2015-03-01

    Brazing experiments on commercially-pure copper plates, using brazing filler metal (MBF-2005), are conducted at temperatures in the range of 650-750 °C for time-durations in the range of 5-15 min. Shear tests for braze-joints involved use of a universal testing machine. Based on the shear-test results, a new brazing cycle has been developed that corresponds to the greatest shear strength of the braze-joint. The brazing cycle has been performed under a controlled dry-argon atmosphere in a tube furnace. Microscopic observations were made by use of both optical and electron microscopes; whereas surface roughness measurements were made by using a TR100 Surface Roughness Tester. It is found that successful brazing and good wetting can be achieved by the least voids by using an average surface roughness (Ra value) for the base material.

  1. Selection of informative parameters of vibroacoustic processes

    NASA Technical Reports Server (NTRS)

    Koshek, L. N.

    1973-01-01

    The problem of selecting informative parameters of vibro-acoustic processes and the construction of apparatus for their determination are discussed. It is assumed that the processes being investigated are structurally uniform and either purely random or contain not very many determinative components.

  2. Effect of processing parameters on reaction bonding of silicon nitride

    NASA Technical Reports Server (NTRS)

    Richman, M. H.; Gregory, O. J.; Magida, M. B.

    1980-01-01

    Reaction bonded silicon nitride was developed. The relationship between the various processing parameters and the resulting microstructures was to design and synthesize reaction bonded materials with improved room temperature mechanical properties.

  3. Surveillance of industrial processes with correlated parameters

    DOEpatents

    White, A.M.; Gross, K.C.; Kubic, W.L.; Wigeland, R.A.

    1996-12-17

    A system and method for surveillance of an industrial process are disclosed. The system and method includes a plurality of sensors monitoring industrial process parameters, devices to convert the sensed data to computer compatible information and a computer which executes computer software directed to analyzing the sensor data to discern statistically reliable alarm conditions. The computer software is executed to remove serial correlation information and then calculate Mahalanobis distribution data to carry out a probability ratio test to determine alarm conditions. 10 figs.

  4. Surveillance of industrial processes with correlated parameters

    DOEpatents

    White, Andrew M.; Gross, Kenny C.; Kubic, William L.; Wigeland, Roald A.

    1996-01-01

    A system and method for surveillance of an industrial process. The system and method includes a plurality of sensors monitoring industrial process parameters, devices to convert the sensed data to computer compatible information and a computer which executes computer software directed to analyzing the sensor data to discern statistically reliable alarm conditions. The computer software is executed to remove serial correlation information and then calculate Mahalanobis distribution data to carry out a probability ratio test to determine alarm conditions.

  5. Drug Development Process

    MedlinePlus

    ... Approvals The Drug Development Process The Drug Development Process Share Tweet Linkedin Pin it More sharing options ... public. More Information More in The Drug Development Process Step 1: Discovery and Development Step 2: Preclinical ...

  6. Visual parameter optimisation for biomedical image processing

    PubMed Central

    2015-01-01

    Background Biomedical image processing methods require users to optimise input parameters to ensure high-quality output. This presents two challenges. First, it is difficult to optimise multiple input parameters for multiple input images. Second, it is difficult to achieve an understanding of underlying algorithms, in particular, relationships between input and output. Results We present a visualisation method that transforms users' ability to understand algorithm behaviour by integrating input and output, and by supporting exploration of their relationships. We discuss its application to a colour deconvolution technique for stained histology images and show how it enabled a domain expert to identify suitable parameter values for the deconvolution of two types of images, and metrics to quantify deconvolution performance. It also enabled a breakthrough in understanding by invalidating an underlying assumption about the algorithm. Conclusions The visualisation method presented here provides analysis capability for multiple inputs and outputs in biomedical image processing that is not supported by previous analysis software. The analysis supported by our method is not feasible with conventional trial-and-error approaches. PMID:26329538

  7. Effects of process parameters on hydrothermal carbonization

    NASA Astrophysics Data System (ADS)

    Uddin, Md. Helal

    In recent years there has been increased research activity in renewable energy, especially upgrading widely available lignicellulosic biomass, in a bid to counter the increasing environmental concerns related with the use of fossil fuels. Hydrothermal carbonization (HTC), also known as wet torrefaction or hot water pretreatment, is a process for pretreatment of diverse lignocellulosic biomass feedstocks, where biomass is treated under subcritical water conditions in short contact time to produce high-value products. The products of this process are: a solid mass characterized as biochar/biocoal/biocarbon, which is homogeneous, energy dense, and hydrophobic; a liquid stream composed of five and six carbon sugars, various organic acids, and 5-HMF; and a gaseous stream, mainly CO2. A number of process parameters are considered important for the extensive application of the HTC process. Primarily, reaction temperature determines the characteristics of the products. In the solid product, the oxygen carbon ratio decreases with increasing reaction temperature and as a result, HTC biochar has the similar characteristics to low rank coal. However, liquid and gaseous stream compositions are largely correlated with the residence time. Biomass particle size can also limit the reaction kinetics due to the mass transfer effect. Recycling of process water can help to minimize the utility consumption and reduce the waste treatment cost as a result of less environmental impact. Loblolly pine was treated in hot compressed water at 200 °C, 230 °C, and 260 °C with 5:1 water:biomass mass ratio to investigate the effects of process parameters on HTC. The solid product were characterized by their mass yields, higher heating values (HHV), and equilibrium moisture content (EMC), while the liquid were characterized by their total organic carbon content and pH value.

  8. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    SciTech Connect

    Ghosh, Subrata Kumar; Bandyopadhyay, Kaushik; Saha, Partha

    2014-07-01

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO{sub 2} and B{sub 4}C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were produced in Al-MMC through SHS. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB{sub 2} and Al{sub 2}O{sub 3} in the composite.

  9. Screw thread parameter measurement system based on image processing method

    NASA Astrophysics Data System (ADS)

    Rao, Zhimin; Huang, Kanggao; Mao, Jiandong; Zhang, Yaya; Zhang, Fan

    2013-08-01

    In the industrial production, as an important transmission part, the screw thread is applied extensively in many automation equipments. The traditional measurement methods of screw thread parameter, including integrated test methods of multiparameters and the single parameter measurement method, belong to contact measurement method. In practical the contact measurement exists some disadvantages, such as relatively high time cost, introducing easily human error and causing thread damage. In this paper, as a new kind of real-time and non-contact measurement method, a screw thread parameter measurement system based on image processing method is developed to accurately measure the outside diameter, inside diameter, pitch diameter, pitch, thread height and other parameters of screw thread. In the system the industrial camera is employed to acquire the image of screw thread, some image processing methods are used to obtain the image profile of screw thread and a mathematics model is established to compute the parameters. The C++Builder 6.0 is employed as the software development platform to realize the image process and computation of screw thread parameters. For verifying the feasibility of the measurement system, some experiments were carried out and the measurement errors were analyzed. The experiment results show the image measurement system satisfies the measurement requirements and suitable for real-time detection of screw thread parameters mentioned above. Comparing with the traditional methods the system based on image processing method has some advantages, such as, non-contact, easy operation, high measuring accuracy, no work piece damage, fast error analysis and so on. In the industrial production, this measurement system can provide an important reference value for development of similar parameter measurement system.

  10. Design of Experiments to Study the Impact of Process Parameters on Droplet Size and Development of Non-Invasive Imaging Techniques in Tablet Coating.

    PubMed

    Dennison, Thomas J; Smith, Julian; Hofmann, Michael P; Bland, Charlotte E; Badhan, Raj K; Al-Khattawi, Ali; Mohammed, Afzal R

    2016-01-01

    Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats. PMID:27548263

  11. Design of Experiments to Study the Impact of Process Parameters on Droplet Size and Development of Non-Invasive Imaging Techniques in Tablet Coating

    PubMed Central

    Dennison, Thomas J.; Smith, Julian; Hofmann, Michael P.; Bland, Charlotte E.; Badhan, Raj K.; Al-Khattawi, Ali; Mohammed, Afzal R.

    2016-01-01

    Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats. PMID:27548263

  12. Image processing method for multicore fiber geometric parameters

    NASA Astrophysics Data System (ADS)

    Zhang, Chuanbiao; Ning, Tigang; Li, Jing; Li, Chao; Ma, Shaoshuo

    2016-05-01

    An image processing method has been developed to obtain multicore fiber geometric parameters. According to the characteristics of multicore fiber, we using MATLAB to processing the sectional view of the multicore fiber (MCF), and the algorithm mainly concludes the following steps: filter out image noise, edge detection, use an appropriate threshold for boundary extraction and an improved curve-fitting algorithm for reconstruction the cross section, then we get the relative geometric parameters of the MCF in pixels. We also compares different edge detection operator and analyzes each detection results, which can provide a meaningful reference for edge detection.

  13. Thermo-Mechanical Processing Parameters for the INCONEL ALLOY 740

    SciTech Connect

    Ludtka, G.M.; Smith, G.

    2007-11-19

    In 2000, a Cooperative Research and Development Agreement (CRADA) was undertaken between the Oak Ridge National Laboratory (ORNL) and the Special Metals Corporation (SMC) to determine the mechanical property response of the IN740 alloy to help establish thermo-mechanical processing parameters for the use of this alloy in supercritical and ultra-critical boiler tubes with the potential for other end uses. SMC had developed an alloy, commercially known as INCONEL alloy 740, which exhibited various beneficial physical, mechanical, and chemical properties. As part of SMC's on-going efforts to optimize this alloy for targeted boiler applications there was a need to develop an understanding of the thermo-mechanical response of the material, characterize the resulting microstructure from this processing, and possibly, utilize models to develop the appropriate processing scheme for this product.

  14. The optimization of operating parameters on microalgae upscaling process planning.

    PubMed

    Ma, Yu-An; Huang, Hsin-Fu; Yu, Chung-Chyi

    2016-03-01

    The upscaling process planning developed in this study primarily involved optimizing operating parameters, i.e., dilution ratios, during process designs. Minimal variable cost was used as an indicator for selecting the optimal combination of dilution ratios. The upper and lower mean confidence intervals obtained from the actual cultured cell density data were used as the final cell density stability indicator after the operating parameters or dilution ratios were selected. The process planning method and results were demonstrated through three case studies of batch culture simulation. They are (1) final objective cell densities were adjusted, (2) high and low light intensities were used for intermediate-scale cultures, and (3) the number of culture days was expressed as integers for the intermediate-scale culture. PMID:26739144

  15. Stellar atmospheric parameter estimation using Gaussian process regression

    NASA Astrophysics Data System (ADS)

    Bu, Yude; Pan, Jingchang

    2015-02-01

    As is well known, it is necessary to derive stellar parameters from massive amounts of spectral data automatically and efficiently. However, in traditional automatic methods such as artificial neural networks (ANNs) and kernel regression (KR), it is often difficult to optimize the algorithm structure and determine the optimal algorithm parameters. Gaussian process regression (GPR) is a recently developed method that has been proven to be capable of overcoming these difficulties. Here we apply GPR to derive stellar atmospheric parameters from spectra. Through evaluating the performance of GPR on Sloan Digital Sky Survey (SDSS) spectra, Medium resolution Isaac Newton Telescope Library of Empirical Spectra (MILES) spectra, ELODIE spectra and the spectra of member stars of galactic globular clusters, we conclude that GPR can derive stellar parameters accurately and precisely, especially when we use data preprocessed with principal component analysis (PCA). We then compare the performance of GPR with that of several widely used regression methods (ANNs, support-vector regression and KR) and find that with GPR it is easier to optimize structures and parameters and more efficient and accurate to extract atmospheric parameters.

  16. Laser forming process development

    SciTech Connect

    Blake, R.J.

    1996-12-31

    This paper is a summary of the activities performed for the process development of laser thermal forming sheet metal parts in support of rapid prototyping. A 400 watt pulsed Nd:YAG laser and 50 watt desktop CO{sub 2} laser were used during initial process development. Several tool-assisted laser forming approaches were conceived during the development of the process, and simple fixtures for process development/understanding were used throughout all testing. Much of the actual forming was performed with the base material in an unfixtured state. CRES (304) was used for baseline development, but the effort was directed toward forming titanium (e.g., 6Al-4V, 15V-3Cr-3Sn-3Al). Several DOE (i.e., Design of Experiment) techniques were employed during development and a Neural Net Computer Model was conceived for process control. This program was a joint effort in cooperation with the American Welding Society under contract with the Defense Advanced Research Projects Agency (DARPA). A synopsis of the laser forming process development, future opportunities, and applications are presented.

  17. Effect of processing parameters on autoclaved PMR polyimide composites

    NASA Technical Reports Server (NTRS)

    Vannucci, R. D.

    1977-01-01

    A study was conducted to determine the effect of processing parameters on the processability and properties of autoclaved fiber reinforced PMR polyimide composites. Composites were fabricated from commercially available graphite fabric and glass fabric PMR polyimide prepreg materials. Process parameters investigated included degree of resin advancement, heating rate, and cure pressure. Composites were inspected for porosity by ultrasonic C scan and photomicrographic examination. Processing characteristics for each set of process parameters and the effect of process parameters on composite mechanical properties at room temperature and 600 F are described.

  18. The influence of processing parameters on microstructural development of low-weight-percent primary, pro-eutectic, dendritic alloys during directional solidification

    NASA Technical Reports Server (NTRS)

    Grugel, R. N.; Kim, Shinwoo; Woodward, Tracey; Wang, T. G.

    1992-01-01

    Alloy compositions centering about Sn- 5 to 15 wt pct Al and Pb- 4 to 20 wt pct Cu have been directionally solidified as a function of growth rate and orientation with respect to earth's gravity vector. The effect of these processing variables on macrosegregation is presented, and the consequence of a structural transition from primary columnar to equiaxed dendritic growth is examined. Effects detrimental to microstructure and attributed to density variations are shown to be minimized by a novel processing technique. In view of the ground-based results, some considerations follow regarding what might be gained by solidifying these alloys in a microgravity environment.

  19. Development of metallization process

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1983-01-01

    A non lead frit paste is evaluated. A two step process is discussed where the bulk of the metallization is Mo/Sn but a small ohmic pad is silver. A new matrix of paste formulations is developed. A variety of tests are performed on paste samples to determine electrical, thermal and structural properties.

  20. A Few Steps Forward in the Process of Looking Back: Setting Parameters for a Self-Study of Administrative and Program Development Work over 18 Years

    ERIC Educational Resources Information Center

    Roose, Deborah

    2010-01-01

    Many self-studies focus on an individual or several teacher educators. Although there have been self-studies undertaken by teacher education administrators, there is relatively little research that focuses specifically on an administrator's program development work in teacher education. This self-study examines one teacher education…

  1. BIOGAS Process development

    SciTech Connect

    Ghosh, S.; Mensinger, M.C.; Sajjad, A.; Henry, M.P.

    1984-01-01

    The overall objective of the program is to demonstrate and commercialize the IGT two-phase BIOGAS Process for optimized methane production from, and simultaneous stabilization of, municipal solid waste (MSW). The specific objective of the current program is to conduct a laboratory-scale investigation of simple, cost-effective feed pretreatment techniques and selected digestion reactor designs to optimize methane production from MSW-sludge blends, and to select the best pretreatment and digestion conditions for testing during the subsequent program for process development unit (PDU) operation. A significant portion of the program efforts to date has been directed at evaluating and/or developing feeding, mixing and discharging systems for handling high concentration, large particle size RDF slurries for anaerobic digestion processes. The performance of such processes depends significantly on the operational success of these subsystems. The results of the subsystem testing have been implemented in the design and operation of the 10-L, 20-L, and 125-L digesters. These results will also be utilized to design the CSTR and the upflow digesters of a large two-phase system. Data collected during the initial phase of this research showed in general that methane production from RDF decreased as the loading rate was increased. Thermophilic digestion did not appear to be significantly better than mesophlic digestion. 9 figures, 3 tables.

  2. Optimization of process parameters for extrusion cooking of low amylose rice flour blended with seeded banana and carambola pomace for development of minerals and fiber rich breakfast cereal.

    PubMed

    Borah, Anjan; Lata Mahanta, Charu; Kalita, Dipankar

    2016-01-01

    The low-amylose rice flour, seeded banana (Musa balbisiana, ABB) and carambola (Averrhoa carambola L.) pomace blends were extruded to prepare ready to eat breakfast cereal in a single-screw extruder. Response surface methodology using a central composite design was used to evaluate effect of independent variables, namely blend ratio (80:10:10 - 60:30:10 of low-amylose rice flour, seeded banana and carambola pomace), screw speed (200 - 400 rpm), barrel temperature (90 - 130 (°)C) and feed moisture content (9 - 21 g/100 g, wet basis) on product responses. Quadratic polynomial equations were also obtained by multiple regression analysis. The predicted models were adequate based on lack-of-fit test and coefficient of determination obtained. The feed moisture content had critical effect on all response variables. The compromised optimal conditions obtained by numerical integration for development of extrudates were: screw speed of 350 rpm, barrel temperature of 120 (°)C, feed moisture content of 12 g/100 g and 65:25:10 of blend ratio of feed. In the optimized condition low-amylose rice blend is found to have better physicochemical properties (water absorption index of 481.79 g/100 g; water solubility index of 44.13 g/100 g) and dietary fiber content of 21.35 g/100 g respectively. The developed breakfast cereal showed considerable amount of minerals (Mg and K) and overall acceptability was found to be 7.8. PMID:26787944

  3. Characteristics, Process Parameters, and Inner Components of Anaerobic Bioreactors

    PubMed Central

    Abdelgadir, Awad; Chen, Xiaoguang; Liu, Jianshe; Xie, Xuehui; Zhang, Jian; Zhang, Kai; Wang, Heng; Liu, Na

    2014-01-01

    The anaerobic bioreactor applies the principles of biotechnology and microbiology, and nowadays it has been used widely in the wastewater treatment plants due to their high efficiency, low energy use, and green energy generation. Advantages and disadvantages of anaerobic process were shown, and three main characteristics of anaerobic bioreactor (AB), namely, inhomogeneous system, time instability, and space instability were also discussed in this work. For high efficiency of wastewater treatment, the process parameters of anaerobic digestion, such as temperature, pH, Hydraulic retention time (HRT), Organic Loading Rate (OLR), and sludge retention time (SRT) were introduced to take into account the optimum conditions for living, growth, and multiplication of bacteria. The inner components, which can improve SRT, and even enhance mass transfer, were also explained and have been divided into transverse inner components, longitudinal inner components, and biofilm-packing material. At last, the newly developed special inner components were discussed and found more efficient and productive. PMID:24672798

  4. Characteristics, process parameters, and inner components of anaerobic bioreactors.

    PubMed

    Abdelgadir, Awad; Chen, Xiaoguang; Liu, Jianshe; Xie, Xuehui; Zhang, Jian; Zhang, Kai; Wang, Heng; Liu, Na

    2014-01-01

    The anaerobic bioreactor applies the principles of biotechnology and microbiology, and nowadays it has been used widely in the wastewater treatment plants due to their high efficiency, low energy use, and green energy generation. Advantages and disadvantages of anaerobic process were shown, and three main characteristics of anaerobic bioreactor (AB), namely, inhomogeneous system, time instability, and space instability were also discussed in this work. For high efficiency of wastewater treatment, the process parameters of anaerobic digestion, such as temperature, pH, Hydraulic retention time (HRT), Organic Loading Rate (OLR), and sludge retention time (SRT) were introduced to take into account the optimum conditions for living, growth, and multiplication of bacteria. The inner components, which can improve SRT, and even enhance mass transfer, were also explained and have been divided into transverse inner components, longitudinal inner components, and biofilm-packing material. At last, the newly developed special inner components were discussed and found more efficient and productive. PMID:24672798

  5. Combining Noise Factors and Process Parameters in a Response Surface

    SciTech Connect

    Wyckoff, J.J.

    1998-03-19

    This presentation covers the strategy and analysis of an experiment to characterize a gas tungsten arc welding process. The experiment combined four uncontrolled noise factors and four controlled process parameters. A nontraditional response surface design was employed. Multiple responses were modeled. Optimal settings for the process parameters to successfully weld the widest range of the pertinent product features were identified. Thus, the process was made ''robust'' against ''noise'' factors. Comparisons are made between the experimental and analytical approach taken versus the Taguchi style of experimentation and analysis. This comparison is mainly done with respect to the information gained, such as product design criteria, incoming material specifications, and process adjustments for nonconforming material.

  6. Optimization of polyetherimide processing parameters for optical interconnect applications

    NASA Astrophysics Data System (ADS)

    Zhao, Wei; Johnson, Peter; Wall, Christopher

    2015-10-01

    ULTEM® polyetherimide (PEI) resins have been used in opto-electronic markets since the optical properties of these materials enable the design of critical components under tight tolerances. PEI resins are the material of choice for injection molded integrated lens applications due to good dimensional stability, near infrared (IR) optical transparency, low moisture uptake and high heat performance. In most applications, parts must be produced consistently with minimal deviations to insure compatibility throughout the lifetime of the part. With the large number of lenses needed for this market, injection molding has been optimized to maximize the production rate. These optimized parameters for high throughput may or may not translate to an optimized optical performance. In this paper, we evaluate and optimize PEI injection molding processes with a focus on optical property performance. A commonly used commercial grade was studied to determine factors and conditions which contribute to optical transparency, color, and birefringence. Melt temperature, mold temperature, injection speed and cycle time were varied to develop optimization trials and evaluate optical properties. These parameters could be optimized to reduce in-plane birefringence from 0.0148 to 0.0006 in this study. In addition, we have studied an optically smooth, sub-10nm roughness mold to re-evaluate material properties with minimal influence from mold quality and further refine resin and process effects for the best optical performance.

  7. Fuzzy control of the production environment process parameters

    NASA Astrophysics Data System (ADS)

    Izvekov, V. N.

    2015-04-01

    The fuzzy control process for support of given microclimatic production environment process parameters with loss of one from values, regulating regime of process was shown. The structural schematic decisions with algorithm of functioning and oriented to existing apparatus (means of realization) was presented.

  8. ASRM test report: Autoclave cure process development

    NASA Technical Reports Server (NTRS)

    Nachbar, D. L.; Mitchell, Suzanne

    1992-01-01

    ASRM insulated segments will be autoclave cured following insulation pre-form installation and strip wind operations. Following competitive bidding, Aerojet ASRM Division (AAD) Purchase Order 100142 was awarded to American Fuel Cell and Coated Fabrics Company, Inc. (Amfuel), Magnolia, AR, for subcontracted insulation autoclave cure process development. Autoclave cure process development test requirements were included in Task 3 of TM05514, Manufacturing Process Development Specification for Integrated Insulation Characterization and Stripwind Process Development. The test objective was to establish autoclave cure process parameters for ASRM insulated segments. Six tasks were completed to: (1) evaluate cure parameters that control acceptable vulcanization of ASRM Kevlar-filled EPDM insulation material; (2) identify first and second order impact parameters on the autoclave cure process; and (3) evaluate insulation material flow-out characteristics to support pre-form configuration design.

  9. Parameter tuning of PVD process based on artificial intelligence technique

    NASA Astrophysics Data System (ADS)

    Norlina, M. S.; Diyana, M. S. Nor; Mazidah, P.; Rusop, M.

    2016-07-01

    In this study, an artificial intelligence technique is proposed to be implemented in the parameter tuning of a PVD process. Due to its previous adaptation in similar optimization problems, genetic algorithm (GA) is selected to optimize the parameter tuning of the RF magnetron sputtering process. The most optimized parameter combination obtained from GA's optimization result is expected to produce the desirable zinc oxide (ZnO) thin film from the sputtering process. The parameters involved in this study were RF power, deposition time and substrate temperature. The algorithm was tested to optimize the 25 datasets of parameter combinations. The results from the computational experiment were then compared with the actual result from the laboratory experiment. Based on the comparison, GA had shown that the algorithm was reliable to optimize the parameter combination before the parameter tuning could be done to the RF magnetron sputtering machine. In order to verify the result of GA, the algorithm was also been compared to other well known optimization algorithms, which were, particle swarm optimization (PSO) and gravitational search algorithm (GSA). The results had shown that GA was reliable in solving this RF magnetron sputtering process parameter tuning problem. GA had shown better accuracy in the optimization based on the fitness evaluation.

  10. Metal cutting analogy for establishing Friction Stir Welding process parameters

    NASA Astrophysics Data System (ADS)

    Stafford, Sylvester Allen

    A friction stir weld (FSW) is a solid state joining operation whose processing parameters are currently determined by lengthy trial and error methods. To implement FSWing rapidly in various applications will require an approach for predicting process parameters based on the physics of the process. Based on hot working conditions for metals, a kinematic model has been proposed for calculating the shear strain and shear strain rates during the FSW process, validation of the proposed model with direct measuring is difficult however. Since the shear strain and shear strain rates predicted for the FSW process, are similar to those predicted in metal cutting, validation of the FSW algorithms with microstructural studies of metal chips may be possible leading to the ability to predict FSW processing parameters.

  11. Life Detection System DTIVA for Monitoring Parameter in Fossilization Process

    NASA Astrophysics Data System (ADS)

    Gómez, F.; Garcia-Descalzo, L.; Cockell, C. S.; Schwendner, P.; Rettberg, P.; Beblo-Vranesevic, K.; Bohmeier, M.; Rabbow, E.; Westall, F.; Gaboyer, F.; Walter, N.; Moissl-Eichinger, M.; Perras, A.; Amils, R.; Malki, M.; Ehrenfreund, P.; Monaghan, E.; Marteinsson, V.; Vannier, P.

    2016-05-01

    Using Life Detection System LDS we followed the physicochemical parameter in a growth culture under fossilization/mineralization-induced process with the objectives of biomarkers detection. Biomarkers study is crucial for the search for life on Mars.

  12. Predicting parameters of degradation succession processes of Tibetan Kobresia grasslands

    NASA Astrophysics Data System (ADS)

    Lin, L.; Li, Y. K.; Xu, X. L.; Zhang, F. W.; Du, Y. G.; Liu, S. L.; Guo, X. W.; Cao, G. M.

    2015-08-01

    In the past two decades, increasing human activity (i.e., overgrazing) in the Tibetan Plateau has strongly influenced plant succession processes, resulting in the degradation of alpine grasslands. Therefore, it is necessary to diagnose the degree of degradation to enable implementation of appropriate management for sustainable exploitation and protection of alpine grasslands. Here, we investigated environmental factors and plant functional group quantity factors (PFGs) during the alpine grassland succession processes. Principal component analysis (PCA) was used to identify the parameters indicative of degradation. We divided the entire degradation process into six stages. PFG types shifted from rhizome bunch grasses to rhizome plexus and dense plexus grasses during the degradation process. Leguminosae and Gramineae plants were replaced by Sedges during the advanced stages of degradation. The PFGs were classified into two reaction groups: the grazing-sensitive group, containing Kobresia humilis Mey, and Gramineae and Leguminosae plants, and the grazing-insensitive group, containing Kobresia pygmaea Clarke. The first group was correlated with live root biomass in the surface soil (0-10 cm), whereas the second group was strongly correlated with mattic epipedon thickness and K. pygmaea characteristics. The degree of degradation of alpine meadows may be delineated by development of mattic epipedon and PFG composition. Thus, meadows could be easily graded and their use adjusted based on our scaling system, which would help prevent irreversible degradation of important grasslands. Because relatively few environmental factors are investigated, this approach can save time and labor to formulate a conservation management plan for degraded alpine meadows.

  13. Predicting parameters of degradation succession processes of Tibetan Kobresia grasslands

    NASA Astrophysics Data System (ADS)

    Lin, L.; Li, Y. K.; Xu, X. L.; Zhang, F. W.; Du, Y. G.; Liu, S. L.; Guo, X. W.; Cao, G. M.

    2015-11-01

    In the past two decades, increasing human activity (i.e., overgrazing) in the Tibetan Plateau has strongly influenced plant succession processes, resulting in the degradation of alpine grasslands. Therefore, it is necessary to diagnose the degree of degradation to enable implementation of appropriate management for sustainable exploitation and protection of alpine grasslands. Here, we investigated environmental factors and plant functional group (PFG) quantity factors during the alpine grassland succession processes. Principal component analysis (PCA) was used to identify the parameters indicative of degradation. We divided the entire degradation process into six stages. PFG types shifted from rhizome bunchgrasses to rhizome plexus and dense-plexus grasses during the degradation process. Leguminosae and Gramineae plants were replaced by sedges during the advanced stages of degradation. The PFGs were classified into two reaction groups: the grazing-sensitive group, containing Kobresia humilis Mey, and Gramineae and Leguminosae plants, and the grazing-insensitive group, containing Kobresia pygmaea Clarke. The first group was correlated with live root biomass in the surface soil (0-10 cm), whereas the second group was strongly correlated with mattic epipedon thickness and K. pygmaea characteristics. The degree of degradation of alpine meadows may be delineated by development of mattic epipedon and PFG composition. Thus, meadows could be easily graded and their use adjusted based on our scaling system, which would help prevent irreversible degradation of important grasslands. Because relatively few environmental factors are investigated, this approach can save time and labor to formulate a conservation management plan for degraded alpine meadows.

  14. Sensitivities of bipolar junction transistor electrical parameters to processing variables

    NASA Astrophysics Data System (ADS)

    Abdulkarim, H. S.

    1980-03-01

    Variations and sensitivities of bipolar junction transistor (BJT) electrical parameters to processing variables were examined. The functional dependence of these sensitivities on the processing schedule employed was estimated. Some design criteria or guidelines that should be followed to reduce the sensitivities of electrical parameters and to minimize yield loss were determined. The BJT parameters considered were electrical parameters of the Ebers-Moll and hybrid-pi models, as well as some device parameters that were useful for the characterization of processing results. The processing variables considered were time and temperature for each of the processing steps of the double diffusion method, physical constants that influence the impurity distribution in silicon, and device dimensions. In evaluating the impurity atom distribution, the diffusion coefficient was assumed to be independent of impurity concentration and the superposition model was assumed for the interaction of the two oppositely charged impurities. In evaluating the electrical parameters, use of a one dimensional model and the modified Moll-Ross relations were assumed to be adequate in relating variations in electrical characteristics to variations in processing variables and physical properties.

  15. Distributed parameter approach to the dynamics of complex biological processes

    SciTech Connect

    Lee, T.T.; Wang, F.Y.; Newell, R.B.

    1999-10-01

    Modeling and simulation of a complex biological process for the removal of nutrients (nitrogen and phosphorus) from municipal wastewater are addressed. The model developed in this work employs a distributed-parameter approach to describe the behavior of components within three different bioreaction zones and the behavior of sludge in the anaerobic zone and soluble phosphate in the aerobic zone in two experiments. Good results are achieved despite the apparent plant-model mismatch, such as uncertainties with the behavior of phosphorus-accumulating organisms. Validation of the proposed secondary-settler model shows that it is superior to two state-of-the-art models in terms of the sum of the square relative errors.

  16. LIMB PROCESS DEVELOPMENT STUDIES

    EPA Science Inventory

    The report covers basic and applied studies concerned with three Limestone Injection Multistage Burner (LIMB) process objectives: (1) avoiding degradation of collection efficiency in the electrostatic precipitator (ESP) during LIMB, (2) achieving satisfactory sulfur dioxide (SO2)...

  17. Optimal parameters of leader development in lightning

    NASA Technical Reports Server (NTRS)

    Petrov, N. I.; Petrova, G. N.

    1991-01-01

    The dependences between the different parameters of a leader in lightning are obtained theoretically. The physical mechanism of the instability leading to the formation of the streamer zone is proposed. The instability has the wave nature and is caused by the self-influence effects of the space charge. Using a stability condition of the leader propagation, a dependence is obtained between the current across the leader head and its velocity of motion. The dependence of the streamer zone length on the gap length is also obtained. It is shown that the streamer zone length is saturated with the increasing of the gap length. A comparison between the obtained dependences and the experimental data is presented.

  18. Silicon web process development

    NASA Technical Reports Server (NTRS)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Skutch, M. E.; Driggers, J. M.; Hopkins, R. H.

    1981-01-01

    The silicon web process takes advantage of natural crystallographic stabilizing forces to grow long, thin single crystal ribbons directly from liquid silicon. The ribbon, or web, is formed by the solidification of a liquid film supported by surface tension between two silicon filaments, called dendrites, which border the edges of the growing strip. The ribbon can be propagated indefinitely by replenishing the liquid silicon as it is transformed to crystal. The dendritic web process has several advantages for achieving low cost, high efficiency solar cells. These advantages are discussed.

  19. Chemical waterflood process development

    SciTech Connect

    Chang, H.L.

    1980-04-01

    A waterflood process is claimed wherein a slug of biopolymer is injected into a formation, followed by a slug of synthetic polymer. The biopolymer slug protects the synthetic polymer from degradation due to presence of salts or surfactants in the formation.

  20. Silicon web process development

    NASA Technical Reports Server (NTRS)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Blais, P. D.; Davis, J. R., Jr.

    1977-01-01

    Thirty-five (35) furnace runs were carried out during this quarter, of which 25 produced a total of 120 web crystals. The two main thermal models for the dendritic growth process were completed and are being used to assist the design of the thermal geometry of the web growth apparatus. The first model, a finite element representation of the susceptor and crucible, was refined to give greater precision and resolution in the critical central region of the melt. The second thermal model, which describes the dissipation of the latent heat to generate thickness-velocity data, was completed. Dendritic web samples were fabricated into solar cells using a standard configuration and a standard process for a N(+) -P-P(+) configuration. The detailed engineering design was completed for a new dendritic web growth facility of greater width capability than previous facilities.

  1. Development of metallization process

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1983-01-01

    Solar cells were produced using a Mo/Sn/TiH screen printed paste with a lead/borosilicate frit that are electrically comparable to control silver cells. The process is currently unsuccessful because the soldering of interconnects to these cells has proved difficult. Future work will investigate using CO instead of H2 as the reducing gas and putting an ITO coating on the cell prior to metallization.

  2. Development of metallization process

    NASA Astrophysics Data System (ADS)

    Garcia, A., III

    1983-04-01

    Solar cells were produced using a Mo/Sn/TiH screen printed paste with a lead/borosilicate frit that are electrically comparable to control silver cells. The process is currently unsuccessful because the soldering of interconnects to these cells has proved difficult. Future work will investigate using CO instead of H2 as the reducing gas and putting an ITO coating on the cell prior to metallization.

  3. Developments in Signature Process Control

    NASA Astrophysics Data System (ADS)

    Keller, L. B.; Dominski, Marty

    1993-01-01

    Developments in the adaptive process control technique known as Signature Process Control for Advanced Composites (SPCC) are described. This computer control method for autoclave processing of composites was used to develop an optimum cure cycle for AFR 700B polyamide and for an experimental poly-isoimide. An improved process cycle was developed for Avimid N polyamide. The potential for extending the SPCC technique to pre-preg quality control, press modeling, pultrusion and RTM is briefly discussed.

  4. Process Parameters Optimization in Single Point Incremental Forming

    NASA Astrophysics Data System (ADS)

    Gulati, Vishal; Aryal, Ashmin; Katyal, Puneet; Goswami, Amitesh

    2016-04-01

    This work aims to optimize the formability and surface roughness of parts formed by the single-point incremental forming process for an Aluminium-6063 alloy. The tests are based on Taguchi's L18 orthogonal array selected on the basis of DOF. The tests have been carried out on vertical machining center (DMC70V); using CAD/CAM software (SolidWorks V5/MasterCAM). Two levels of tool radius, three levels of sheet thickness, step size, tool rotational speed, feed rate and lubrication have been considered as the input process parameters. Wall angle and surface roughness have been considered process responses. The influential process parameters for the formability and surface roughness have been identified with the help of statistical tool (response table, main effect plot and ANOVA). The parameter that has the utmost influence on formability and surface roughness is lubrication. In the case of formability, lubrication followed by the tool rotational speed, feed rate, sheet thickness, step size and tool radius have the influence in descending order. Whereas in surface roughness, lubrication followed by feed rate, step size, tool radius, sheet thickness and tool rotational speed have the influence in descending order. The predicted optimal values for the wall angle and surface roughness are found to be 88.29° and 1.03225 µm. The confirmation experiments were conducted thrice and the value of wall angle and surface roughness were found to be 85.76° and 1.15 µm respectively.

  5. Roll compaction process modeling: transfer between equipment and impact of process parameters.

    PubMed

    Souihi, Nabil; Reynolds, Gavin; Tajarobi, Pirjo; Wikström, Håkan; Haeffler, Gunnar; Josefson, Mats; Trygg, Johan

    2015-04-30

    In this study, the roll compaction of an intermediate drug load formulation was performed using horizontally and vertically force fed roll compactors. The horizontally fed roll compactor was equipped with an instrumented roll technology allowing the direct measurement of normal stress at the roll surface, while the vertically fed roll compactor was equipped with a force gauge between the roll axes. Furthermore, characterization of ribbons, granules and tablets was also performed. Ribbon porosity was primarily found to be a function of normal stress, exhibiting a quadratic relationship thereof. A similar quadratic relationship was also observed between roll force and ribbon porosity of the vertically fed roll compactor. The predicted peak pressure (Pmax) using the Johanson model was found to be higher than the measured normal stress, however, the predicted Pmax correlated well with the ribbon relative density/porosity and the majority of downstream properties of granules and tablets, demonstrating its use as a scale-independent parameter. A latent variable model was developed for both the horizontal and vertical fed roll compactors to express ribbon porosity as a function of geometric and process parameters. The model validation, performed with new data, resulted in overall good predictions. This study successfully demonstrated the scale up/transfer between two different roll compactors and revealed that the combined use of design of experiments, latent variable models and in silico predictions result in better understanding of the critical process parameters in roll compaction. PMID:25701630

  6. Silicon Web Process Development

    NASA Technical Reports Server (NTRS)

    Duncan, C. S.; Seidensticker, R. G.; Hopkins, R. H.; Mchugh, J. P.; Hill, F. E.; Heimlich, M. E.; Driggers, J. M.

    1978-01-01

    Progress in the development of techniques to grow silicon web at 25 wq cm/min output rate is reported. Feasibility of web growth with simultaneous melt replenishment is discussed. Other factors covered include: (1) tests of aftertrimmers to improve web width; (2) evaluation of growth lid designs to raise speed and output rate; (3) tests of melt replenishment hardware; and (4) investigation of directed gas flow systems to control unwanted oxide deposition in the system and to improve convective cooling of the web. Compatibility with sufficient solar cell performance is emphasized.

  7. Silicon web process development

    NASA Technical Reports Server (NTRS)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Hill, F. E.; Skutch, M. E.; Driggers, J. M.; Hopkins, R. H.

    1980-01-01

    A barrier crucible design which consistently maintains melt stability over long periods of time was successfully tested and used in long growth runs. The pellet feeder for melt replenishment was operated continuously for growth runs of up to 17 hours. The liquid level sensor comprising a laser/sensor system was operated, performed well, and meets the requirements for maintaining liquid level height during growth and melt replenishment. An automated feedback loop connecting the feed mechanism and the liquid level sensing system was designed and constructed and operated successfully for 3.5 hours demonstrating the feasibility of semi-automated dendritic web growth. The sensitivity of the cost of sheet, to variations in capital equipment cost and recycling dendrites was calculated and it was shown that these factors have relatively little impact on sheet cost. Dendrites from web which had gone all the way through the solar cell fabrication process, when melted and grown into web, produce crystals which show no degradation in cell efficiency. Material quality remains high and cells made from web grown at the start, during, and the end of a run from a replenished melt show comparable efficiencies.

  8. Signal processing development

    NASA Astrophysics Data System (ADS)

    Barrett, T. B.; Marshall, R.; Bloom, J.; Comer, C.; Caulfield, J.; Warde, C.; Salour, M.

    1989-11-01

    This electron microscope has been applied to the study of the growth of thin epitaxial films on silicon substrates. The study of the nature of platinum-silicide films formed by heating evaporated platinum films on these substrates is discussed. The use of ultra high vacuum systems together with a residual gas analyzer (RGA) is discussed as they relate to the preparation of silicides, a dielectric layer of silicon monoxide is evaporated and an ion beam implanter is used to form a special buried layer as a step toward silicon devices. Synthesis and single crystal growth of indium phosphide in a one-step in-situ process at high ambient pressures is discussed. Analysis of heat transfer by convection, conduction, and radiation in a closed pressure vessel is given. A set of source modules and NOS procedures have been prepared to permit easy access to a 3-dimensional, non-isotrophic ray-tracing program (the Jones - Stephenson program). This system is designed to be run on a CDC CYBER computer system or equivalent using the operating system.

  9. Processes and process development in Japan

    NASA Technical Reports Server (NTRS)

    Noda, T.

    1986-01-01

    The commercialization of solar power generation necessitates the development of low cost manufacturing method of silicon suitable for solar cells. The manufacturing methods of semiconductor grade silicon (SEG-Si) and the development of solar grade silicon (SOG-Si) in foreign countries was investigated. It was concluded that the most efficient method of developing such materials was the hydrogen reduction process of trichlorosilane (TCS), using a fluidized bed reactor. The low cost reduction of polysilicon requires cost reductions of raw materials, energy, labor, and capital. These conditions were carefully reviewed. The overall conclusion was that a development program should be based on the TCS-FBR process and that the experimental program should be conducted in test facilities capable of producing 10 tons of silicon granules per year.

  10. Analysis of dip coating processing parameters by double optical monitoring.

    PubMed

    Horowitz, Flavio; Michels, Alexandre F

    2008-05-01

    Double optical monitoring is applied to determine the influence of main process parameters on the formation of sulfated zirconia and self-assembled mesoporous silica solgel films by dip coating. In addition, we analyze, for the first time to the best of our knowledge, the influence of withdrawal speed, temperature, and relative humidity on refractive-index and physical thickness variations (uncertainties of +/-0.005 and +/-7 nm) during the process. Results provide insight into controlled production of single and multilayer films from complex fluids by dip coating. PMID:18449244

  11. Development of the selective coagulation process

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1991-01-01

    The aim of this project is to develop an economical method for producing low-sulfur and low-ash coals using the selective hydrophobic coagulation (SHC) process. This work has been divided into three tasks: (1) project planning and sample acquisition; (2) studies of the fundamental mechanism(s) of the selective coagulation process and the parameters that affect the process of separating coal from both the ash-forming minerals and pyritic sulfur; and (3) bench-scale process development test work to establish the best possible method(s) of separating the hydrophobic and coagula from the dispersed mineral matter.

  12. Diffusion parameters of indium for silicon process modeling

    NASA Astrophysics Data System (ADS)

    Kizilyalli, I. C.; Rich, T. L.; Stevie, F. A.; Rafferty, C. S.

    1996-11-01

    The diffusion parameters of indium in silicon are investigated. Systematic diffusion experiments in dry oxidizing ambients at temperatures ranging from 800 to 1050 °C are conducted using silicon wafers implanted with indium. Secondary-ion-mass spectrometry (SIMS) is used to analyze the dopant distribution before and after heat treatment. The oxidation-enhanced diffusion parameter [R. B. Fair, in Semiconductor Materials and Process Technology Handbook, edited by G. E. McGuire (Noyes, Park Ridge, NJ, 1988); A. M. R. Lin, D. A. Antoniadis, and R. W. Dutton, J. Electrochem. Soc. Solid-State Sci. Technol. 128, 1131 (1981); D. A. Antoniadis and I. Moskowitz, J. Appl. Phys. 53, 9214 (1982)] and the segregation coefficient at the Si/SiO2 interface [R. B. Fair and J. C. C. Tsai, J. Electrochem. Soc. Solid-State Sci. Technol. 125, 2050 (1978)] (ratio of indium concentration in silicon to that in silicon dioxide) are extracted as a function of temperature using SIMS depth profiles and the silicon process simulator PROPHET [M. Pinto, D. M. Boulin, C. S. Rafferty, R. K. Smith, W. M. Coughran, I. C. Kizilyalli, and M. J. Thoma, in IEDM Technical Digest, 1992, p. 923]. It is observed that the segregation coefficient of indium at the Si/SiO2 interface is mIn≪1, similar to boron; however, unlike boron, the segregation coefficient of indium at the Si/SiO2 interface decreases with increasing temperature. Extraction results are summarized in analytical forms suitable for incorporation into other silicon process simulators. Finally, the validity of the extracted parameters is verified by comparing the simulated and measured SIMS profiles for an indium implanted buried-channel p-channel metal-oxide-semiconductor field-effect-transistor [I. C. Kizilyalli, F. A. Stevie, and J. D. Bude, IEEE Electron Device Lett. (1996)] process that involves a gate oxidation and various other thermal processes.

  13. Parameters in selective laser melting for processing metallic powders

    NASA Astrophysics Data System (ADS)

    Kurzynowski, Tomasz; Chlebus, Edward; Kuźnicka, Bogumiła; Reiner, Jacek

    2012-03-01

    The paper presents results of studies on Selective Laser Melting. SLM is an additive manufacturing technology which may be used to process almost all metallic materials in the form of powder. Types of energy emission sources, mainly fiber lasers and/or Nd:YAG laser with similar characteristics and the wavelength of 1,06 - 1,08 microns, are provided primarily for processing metallic powder materials with high absorption of laser radiation. The paper presents results of selected variable parameters (laser power, scanning time, scanning strategy) and fixed parameters such as the protective atmosphere (argon, nitrogen, helium), temperature, type and shape of the powder material. The thematic scope is very broad, so the work was focused on optimizing the process of selective laser micrometallurgy for producing fully dense parts. The density is closely linked with other two conditions: discontinuity of the microstructure (microcracks) and stability (repeatability) of the process. Materials used for the research were stainless steel 316L (AISI), tool steel H13 (AISI), and titanium alloy Ti6Al7Nb (ISO 5832-11). Studies were performed with a scanning electron microscope, a light microscopes, a confocal microscope and a μCT scanner.

  14. Quality of margarine: fats selection and processing parameters.

    PubMed

    Miskandar, Mat Sahri; Man, Yaakob Che; Yusoff, Mohd Suria Affandi; Rahman, Russly Abd

    2005-01-01

    Optimum processing conditions on palm oil-based formulations are required to produce the desired quality margarine. As oils and fats contribute to the overall property of the margarine, this paper will review the importance of beta' tending oils and fats in margarine formulation, effects of the processing parameters -- emulsion temperature, flow-rate, product temperature and pin-worker speed -- on palm oil margarines produced and their subsequent behaviour in storage. Palm oil, which contributes the beta' crystal polymorph and the best alternative to hydrogenated liquid fats, and the processing conditions can affect the margarine consistency by influencing the solid fat content (SFC) and the types of crystal polymorph formed during production as well as in storage. Palm oil, or hydrogenated palm oil and olein, in mixture with oils of beta tending, can veer the product to the beta' crystal form. However, merely having beta' crystal tending oils is not sufficient as the processing conditions are also important. The emulsion temperature had no significant effect on the consistency and polymorphic changes of the product during storage, even though differences were observed during processing. The consistency of margarine during storage was high at low emulsion flow-rates and low at high flow rates. The temperature of the scraped-surface tube-cooler is the most important parameter in margarine processing. High temperature will produce a hardened product with formation of beta-crystals during storage. The speed of the pin-worker is responsible for inducing crystallization but, at the same time, destroys the crystal agglomerates, resulting in melting. PMID:16326646

  15. Effect of spray drying processing parameters on the insecticidal activity of two encapsulated formulations of baculovirus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this work was to evaluate the effect of spray dryer processing parameters on the process yield and insecticidal activity of baculovirus to support the development of this beneficial group of microbes as biopesticides. For each of two baculoviruses [granulovirus (GV) from Pieris rapae (L....

  16. Estimating demographic parameters using hidden process dynamic models.

    PubMed

    Gimenez, Olivier; Lebreton, Jean-Dominique; Gaillard, Jean-Michel; Choquet, Rémi; Pradel, Roger

    2012-12-01

    Structured population models are widely used in plant and animal demographic studies to assess population dynamics. In matrix population models, populations are described with discrete classes of individuals (age, life history stage or size). To calibrate these models, longitudinal data are collected at the individual level to estimate demographic parameters. However, several sources of uncertainty can complicate parameter estimation, such as imperfect detection of individuals inherent to monitoring in the wild and uncertainty in assigning a state to an individual. Here, we show how recent statistical models can help overcome these issues. We focus on hidden process models that run two time series in parallel, one capturing the dynamics of the true states and the other consisting of observations arising from these underlying possibly unknown states. In a first case study, we illustrate hidden Markov models with an example of how to accommodate state uncertainty using Frequentist theory and maximum likelihood estimation. In a second case study, we illustrate state-space models with an example of how to estimate lifetime reproductive success despite imperfect detection, using a Bayesian framework and Markov Chain Monte Carlo simulation. Hidden process models are a promising tool as they allow population biologists to cope with process variation while simultaneously accounting for observation error. PMID:22373775

  17. Unraveling the Processing Parameters in Friction Stir Welding

    NASA Technical Reports Server (NTRS)

    Schneider, Judy; Nunes, Arthur C., Jr.

    2005-01-01

    In friction stir welding (FSW), a rotating threaded pin tool is translated along a weld seam, literally stirring the edges of the seam together. To determine optimal processing parameters for producing a defect free weld, a better understanding of the resulting metal deformation flow path or paths is required. In this study, various markers are used to trace the flow paths of the metal. X-ray radiographs record the segmentation and position of the wire. Several variations in the trajectories can be differentiated within the weld zone.

  18. Correlations of Melt Pool Geometry and Process Parameters During Laser Metal Deposition by Coaxial Process Monitoring

    NASA Astrophysics Data System (ADS)

    Ocylok, Sörn; Alexeev, Eugen; Mann, Stefan; Weisheit, Andreas; Wissenbach, Konrad; Kelbassa, Ingomar

    One major demand of today's laser metal deposition (LMD) processes is to achieve a fail-save build-up regarding changing conditions like heat accumulations. Especially for the repair of thin parts like turbine blades is the knowledge about the correlations between melt pool behavior and process parameters like laser power, feed rate and powder mass stream indispensable. The paper will show the process layout with the camera based coaxial monitoring system and the quantitative influence of the process parameters on the melt pool geometry. Therefore the diameter, length and area of the melt pool are measured by a video analytic system at various parameters and compared with the track wide in cross-sections and the laser spot diameter. The influence of changing process conditions on the melt pool is also investigated. On the base of these results an enhanced process of the build-up of a multilayer one track fillet geometry will be presented.

  19. Developing the JPL Engineering Processes

    NASA Technical Reports Server (NTRS)

    Linick, Dave; Briggs, Clark

    2004-01-01

    This paper briefly recounts the recent history of process reengineering at the NASA Jet Propulsion Laboratory, with a focus on the engineering processes. The JPL process structure is described and the process development activities of the past several years outlined. The main focus of the paper is on the current process structure, the emphasis on the flight project life cycle, the governance approach that lead to Flight Project Practices, and the remaining effort to capture process knowledge at the detail level of the work group.

  20. Monolithic Fuel Fabrication Process Development

    SciTech Connect

    C. R. Clark; N. P. Hallinan; J. F. Jue; D. D. Keiser; J. M. Wight

    2006-05-01

    The pursuit of a high uranium density research reactor fuel plate has led to monolithic fuel, which possesses the greatest possible uranium density in the fuel region. Process developments in fabrication development include friction stir welding tool geometry and cooling improvements and a reduction in the length of time required to complete the transient liquid phase bonding process. Annealing effects on the microstructures of the U-10Mo foil and friction stir welded aluminum 6061 cladding are also examined.

  1. Incorporating Soil Hydraulic Parameter Statistics in Developing Pedo-transfer Functions

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Zhu, J.; Ye, M.; Meyer, P. D.; Pan, F.; Hassan, A. E.

    2007-12-01

    In this study, we develop artificial neural network (ANN) based pedotransfer functions (PTFs) to predict soil hydraulic properties. The PTF approach is an efficient way of translating less costly available data, such as particle-size distributions, soil textures and other geophysical measurements, to soil hydraulic parameters required for numerical simulations and other applications. The ANN PTFs need to be trained before being used to transfer indirect measurements to soil hydraulic parameters. The traditional training process, in general, is to adjust ANN's coefficients to solely minimize the difference between the estimated and measured soil hydraulic parameters. The training process, however, did not consider the distributions of soil hydraulic parameters and the trained neural networks may yield improper distributions, which may severely affect probabilistic predictions. We incorporate the distributions of the soil hydraulic parameters into the ANN PTF development. In addition, it has been observed that PTFs can introduce unrealistic correlations between the output parameters. The unwanted artificial correlations need to be penalized during the training process, since it is well known that parameter correlations have significant effect on predictions. We achieve these two goals by adding two regularization terms to the ANN objective functions. A suite of new neural network models are developed to estimate soil hydraulic parameters. These neural network models have the same input and output variables, but different objective functions, which incorporate sequentially the site soil hydraulic parameter measurements, parameter probability distributions, and parameter correlations.

  2. Exploring control parameters of two photon processes in solutions#

    PubMed Central

    GOSWAMI, DEBABRATA; NAG, AMIT

    2013-01-01

    Two-photon microscopy depends extensively on the two-photon absorption cross-sections of biologically relevant chromophores. High repetition rate (HRR) lasers are essential in multiphoton microscopy for generating satisfactory signal to noise at low average powers. However, HRR lasers generate thermal distortions in samples even with the slightest single photon absorption. We use an optical chopper with HRR lasers to intermittently ‘blank’ irradiation and effectively minimize thermal effects to result in a femtosecond z-scan setup that precisely measures the two-photon absorption (TPA) cross-sections of chromophores. Though several experimental factors impact such TPA measurements, a systematic effort to modulate and influence TPA characteristics is yet to evolve. Here, we present the effect of several control parameters on the TPA process that are independent of chromophore characteristics for femtosecond laser pulse based measurements; and demonstrate how the femtosecond laser pulse repetition rate, chromophore environment and incident laser polarization can become effective control parameters for such nonlinear optical properties. PMID:24098068

  3. Preform Characterization in VARTM Process Model Development

    NASA Technical Reports Server (NTRS)

    Grimsley, Brian W.; Cano, Roberto J.; Hubert, Pascal; Loos, Alfred C.; Kellen, Charles B.; Jensen, Brian J.

    2004-01-01

    Vacuum-Assisted Resin Transfer Molding (VARTM) is a Liquid Composite Molding (LCM) process where both resin injection and fiber compaction are achieved under pressures of 101.3 kPa or less. Originally developed over a decade ago for marine composite fabrication, VARTM is now considered a viable process for the fabrication of aerospace composites (1,2). In order to optimize and further improve the process, a finite element analysis (FEA) process model is being developed to include the coupled phenomenon of resin flow, preform compaction and resin cure. The model input parameters are obtained from resin and fiber-preform characterization tests. In this study, the compaction behavior and the Darcy permeability of a commercially available carbon fabric are characterized. The resulting empirical model equations are input to the 3- Dimensional Infiltration, version 5 (3DINFILv.5) process model to simulate infiltration of a composite panel.

  4. Processes of Expressive Behavior Development.

    ERIC Educational Resources Information Center

    Zivin, Gail

    1986-01-01

    Seventeen processes in the development of expressive behavior are reviewed and coordinated in a framework that is shown to accommodate current perspectives on expressive behavior development. Works of Ekman, Izard, Lewis and Michalson, and Sroufe are briefly reviewed. Neglected areas of research are indicated and the course of expressive behavior…

  5. Effect of processing parameters on the corrosion behaviour of friction stir processed AA 2219 aluminum alloy

    NASA Astrophysics Data System (ADS)

    Surekha, K.; Murty, B. S.; Prasad Rao, K.

    2009-04-01

    The effect of processing parameters (rotation speed and traverse speed) on the corrosion behaviour of friction stir processed high strength precipitation hardenable AA 2219-T87 alloy was investigated. The results indicate that the rotation speed has a major influence in determining the rate of corrosion, which is attributed to the breaking down and dissolution of the intermetallic particles. Corrosion resistance of friction stir processed alloy was studied by potentiodynamic polarization, electrochemical impedance spectroscopy, salt spray and immersion tests.

  6. Automating the training development process

    NASA Technical Reports Server (NTRS)

    Scott, Carol J.

    1993-01-01

    The Automated Training Development System (ATDS) was developed as a training tool for the JPL training environment. ATDS is based on the standard for military training programs and is designed to develop training from a system perspective, focusing on components in terms of the whole process. The principal feature of ATDS is data base maintainability. Everything is contained and maintained within the data base, and, if properly developed, it could be a training component of a software delivery and provided to CM as a controlled item. The analysis, development, design, presentation, and reporting phases in the ATDS instructional design method are illustrated.

  7. Developing the Parameters of Scholarship in Postgraduate Coursework Studies

    ERIC Educational Resources Information Center

    McLay, Allan F.

    2013-01-01

    Scholarship parameters, in relation to postgraduate coursework studies, are developed against the expectations of the Boyer classifications of scholarship (Boyer, 1990) with particular emphasis on the role of minor thesis development. An example is presented in which postgraduate coursework students are required to undertake a three semester minor…

  8. SURFACE WATER QUALITY PARAMETERS FOR MONITORING OIL SHALE DEVELOPMENT

    EPA Science Inventory

    This report develops and recommends prioritized listings of chemical, physical, and biological parameters which can be used to assess the environmental impact of oil shale development on surface water resources. Each of the potential water-related problems is addressed in the con...

  9. On selecting a prior for the precision parameter of Dirichlet process mixture models

    USGS Publications Warehouse

    Dorazio, R.M.

    2009-01-01

    In hierarchical mixture models the Dirichlet process is used to specify latent patterns of heterogeneity, particularly when the distribution of latent parameters is thought to be clustered (multimodal). The parameters of a Dirichlet process include a precision parameter ?? and a base probability measure G0. In problems where ?? is unknown and must be estimated, inferences about the level of clustering can be sensitive to the choice of prior assumed for ??. In this paper an approach is developed for computing a prior for the precision parameter ?? that can be used in the presence or absence of prior information about the level of clustering. This approach is illustrated in an analysis of counts of stream fishes. The results of this fully Bayesian analysis are compared with an empirical Bayes analysis of the same data and with a Bayesian analysis based on an alternative commonly used prior.

  10. Development of a distribution system for measuring nozzle integrative parameters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The experimental system used in this study was equipped with sensors and computer-controlled processing technology. This system was used in the measurement of major performance parameters such as pressure, flux, spray angle, spray distribution character of the nozzle and its integrative performance...

  11. Intelligent Modeling Combining Adaptive Neuro Fuzzy Inference System and Genetic Algorithm for Optimizing Welding Process Parameters

    NASA Astrophysics Data System (ADS)

    Gowtham, K. N.; Vasudevan, M.; Maduraimuthu, V.; Jayakumar, T.

    2011-04-01

    Modified 9Cr-1Mo ferritic steel is used as a structural material for steam generator components of power plants. Generally, tungsten inert gas (TIG) welding is preferred for welding of these steels in which the depth of penetration achievable during autogenous welding is limited. Therefore, activated flux TIG (A-TIG) welding, a novel welding technique, has been developed in-house to increase the depth of penetration. In modified 9Cr-1Mo steel joints produced by the A-TIG welding process, weld bead width, depth of penetration, and heat-affected zone (HAZ) width play an important role in determining the mechanical properties as well as the performance of the weld joints during service. To obtain the desired weld bead geometry and HAZ width, it becomes important to set the welding process parameters. In this work, adaptative neuro fuzzy inference system is used to develop independent models correlating the welding process parameters like current, voltage, and torch speed with weld bead shape parameters like depth of penetration, bead width, and HAZ width. Then a genetic algorithm is employed to determine the optimum A-TIG welding process parameters to obtain the desired weld bead shape parameters and HAZ width.

  12. Optimisation of shock absorber process parameters using failure mode and effect analysis and genetic algorithm

    NASA Astrophysics Data System (ADS)

    Mariajayaprakash, Arokiasamy; Senthilvelan, Thiyagarajan; Vivekananthan, Krishnapillai Ponnambal

    2013-07-01

    The various process parameters affecting the quality characteristics of the shock absorber during the process were identified using the Ishikawa diagram and by failure mode and effect analysis. The identified process parameters are welding process parameters (squeeze, heat control, wheel speed, and air pressure), damper sealing process parameters (load, hydraulic pressure, air pressure, and fixture height), washing process parameters (total alkalinity, temperature, pH value of rinsing water, and timing), and painting process parameters (flowability, coating thickness, pointage, and temperature). In this paper, the process parameters, namely, painting and washing process parameters, are optimized by Taguchi method. Though the defects are reasonably minimized by Taguchi method, in order to achieve zero defects during the processes, genetic algorithm technique is applied on the optimized parameters obtained by Taguchi method.

  13. Optimization of process parameters for the manufacturing of rocket casings: A study using processing maps

    NASA Astrophysics Data System (ADS)

    Avadhani, G. S.

    2003-12-01

    Maraging steels possess ultrahigh strength combined with ductility and toughness and could be easily fabricated and heat-treated. Bulk metalworking of maraging steels is an important step in the component manufacture. To optimize the hot-working parameters (temperature and strain rate) for the ring rolling process of maraging steel used for the manufacture of rocket casings, a systematic study was conducted to characterize the hot working behavior by developing processing maps for γ-iron and an indigenous 250 grade maraging steel. The hot deformation behavior of binary alloys of iron with Ni, Co, and Mo, which are major constituents of maraging steel, is also studied. Results from the investigation suggest that all the materials tested exhibit a domain of dynamic recrystallization (DRX). From the instability maps, it was revealed that strain rates above 10 s-1 are not suitable for hot working of these materials. An important result from the stress-strain behavior is that while Co strengthens γ-iron, Ni and Mo cause flow softening. Temperatures around 1125 °C and strain rate range between 0.001 and 0.1 s-1 are suitable for the hot working of maraging steel in the DRX domain. Also, higher strain rates may be used in the meta-dynamic recrystallization domain above 1075 °C for high strain rate applications such as ring rolling. The microstructural mechanisms identified from the processing maps along with grain size analyses and hot ductility measurements could be used to design hot-working schedules for maraging steel.

  14. ASRM process development in aqueous cleaning

    NASA Technical Reports Server (NTRS)

    Swisher, Bill

    1992-01-01

    Viewgraphs are included on process development in aqueous cleaning which is taking place at the Aerojet Advanced Solid Rocket Motor (ASRM) Division under a NASA Marshall Space and Flight Center contract for design, development, test, and evaluation of the ASRM including new production facilities. The ASRM will utilize aqueous cleaning in several manufacturing process steps to clean case segments, nozzle metal components, and igniter closures. ASRM manufacturing process development is underway, including agent selection, agent characterization, subscale process optimization, bonding verification, and scale-up validation. Process parameters are currently being tested for optimization utilizing a Taguci Matrix, including agent concentration, cleaning solution temperature, agitation and immersion time, rinse water amount and temperature, and use/non-use of drying air. Based on results of process development testing to date, several observations are offered: aqueous cleaning appears effective for steels and SermeTel-coated metals in ASRM processing; aqueous cleaning agents may stain and/or attack bare aluminum metals to various extents; aqueous cleaning appears unsuitable for thermal sprayed aluminum-coated steel; aqueous cleaning appears to adequately remove a wide range of contaminants from flat metal surfaces, but supplementary assistance may be needed to remove clumps of tenacious contaminants embedded in holes, etc.; and hot rinse water appears to be beneficial to aid in drying of bare steel and retarding oxidation rate.

  15. ASRM process development in aqueous cleaning

    NASA Astrophysics Data System (ADS)

    Swisher, Bill

    1992-12-01

    Viewgraphs are included on process development in aqueous cleaning which is taking place at the Aerojet Advanced Solid Rocket Motor (ASRM) Division under a NASA Marshall Space and Flight Center contract for design, development, test, and evaluation of the ASRM including new production facilities. The ASRM will utilize aqueous cleaning in several manufacturing process steps to clean case segments, nozzle metal components, and igniter closures. ASRM manufacturing process development is underway, including agent selection, agent characterization, subscale process optimization, bonding verification, and scale-up validation. Process parameters are currently being tested for optimization utilizing a Taguci Matrix, including agent concentration, cleaning solution temperature, agitation and immersion time, rinse water amount and temperature, and use/non-use of drying air. Based on results of process development testing to date, several observations are offered: aqueous cleaning appears effective for steels and SermeTel-coated metals in ASRM processing; aqueous cleaning agents may stain and/or attack bare aluminum metals to various extents; aqueous cleaning appears unsuitable for thermal sprayed aluminum-coated steel; aqueous cleaning appears to adequately remove a wide range of contaminants from flat metal surfaces, but supplementary assistance may be needed to remove clumps of tenacious contaminants embedded in holes, etc.; and hot rinse water appears to be beneficial to aid in drying of bare steel and retarding oxidation rate.

  16. Statistical analysis of process parameters to eliminate hot cracking of fiber laser welded aluminum alloy

    NASA Astrophysics Data System (ADS)

    Wang, Jin; Wang, Hui-Ping; Wang, Xiaojie; Cui, Haichao; Lu, Fenggui

    2015-03-01

    This paper investigates hot cracking rate in Al fiber laser welding under various process conditions and performs corresponding process optimization. First, effects of welding process parameters such as distance between welding center line and its closest trim edge, laser power and welding speed on hot cracking rate were investigated experimentally with response surface methodology (RSM). The hot cracking rate in the paper is defined as ratio of hot cracking length over the total weld seam length. Based on the experimental results following Box-Behnken design, a prediction model for the hot cracking rate was developed using a second order polynomial function considering only two factor interaction. The initial prediction result indicated that the established model could predict the hot cracking rate adequately within the range of welding parameters being used. The model was then used to optimize welding parameters to achieve cracking-free welds.

  17. Objective Distributed-parameter Estimation Methods For Simulating Meteorological and Hydrological Processes In Mountainous Areas

    NASA Astrophysics Data System (ADS)

    Leavesley, G.; Hay, L.; Viger, R.; de Jong, C.

    The use of distributed-parameter models in mountainous terrain requires the ability to define the spatial and temporal distributions of input meteorological variables and the physical basin characteristics that affect the processes being simulated. Application of these models to complex problems, such as assessing the impacts of land-use and climate change, limits one's ability to calibrate model parameters and necessitates the use of parameter-estimation methods that rely on measurable climate and basin char- acteristics. The increasing availability of high-resolution spatial and temporal data sets now enables the development and evaluation of a variety of parameter-estimation methods over a wide range of climatic and physiographic regions. For example, pa- rameters related to basin characteristics can be estimated from digital soils, vegetation, and topographic databases. Parameters related to the temporal and spatial distribution of meteorological variables, such as precipitation and temperature, can be estimated from multiple linear regression relations using latitude, longitude, and elevation of measurement stations and basin subareas. This approach also supports the use of sta- tistical and dynamical downscaling of atmospheric model output for use in distributed hydrological model applications. A set of tools to objectively apply and evaluate distributed meteorological and hydro- logical parameter-estimation methods, and process models, is being developed using the U.S. Geological Survey's Modular Modeling System (MMS). Tools include meth- ods to analyze model parameters and evaluate the extent to which uncertainty in model parameters affects uncertainty in simulation results. Methodologies that integrate re- motely sensed information with the distributed-model results are being incorporated in the tool set to facilitate the assessment of the spatial and temporal accuracy of model results. An application of selected models and parameter-estimation methods is

  18. Mammalian Cell Culture Process for Monoclonal Antibody Production: Nonlinear Modelling and Parameter Estimation

    PubMed Central

    Selişteanu, Dan; Șendrescu, Dorin; Georgeanu, Vlad

    2015-01-01

    Monoclonal antibodies (mAbs) are at present one of the fastest growing products of pharmaceutical industry, with widespread applications in biochemistry, biology, and medicine. The operation of mAbs production processes is predominantly based on empirical knowledge, the improvements being achieved by using trial-and-error experiments and precedent practices. The nonlinearity of these processes and the absence of suitable instrumentation require an enhanced modelling effort and modern kinetic parameter estimation strategies. The present work is dedicated to nonlinear dynamic modelling and parameter estimation for a mammalian cell culture process used for mAb production. By using a dynamical model of such kind of processes, an optimization-based technique for estimation of kinetic parameters in the model of mammalian cell culture process is developed. The estimation is achieved as a result of minimizing an error function by a particle swarm optimization (PSO) algorithm. The proposed estimation approach is analyzed in this work by using a particular model of mammalian cell culture, as a case study, but is generic for this class of bioprocesses. The presented case study shows that the proposed parameter estimation technique provides a more accurate simulation of the experimentally observed process behaviour than reported in previous studies. PMID:25685797

  19. Mammalian cell culture process for monoclonal antibody production: nonlinear modelling and parameter estimation.

    PubMed

    Selişteanu, Dan; Șendrescu, Dorin; Georgeanu, Vlad; Roman, Monica

    2015-01-01

    Monoclonal antibodies (mAbs) are at present one of the fastest growing products of pharmaceutical industry, with widespread applications in biochemistry, biology, and medicine. The operation of mAbs production processes is predominantly based on empirical knowledge, the improvements being achieved by using trial-and-error experiments and precedent practices. The nonlinearity of these processes and the absence of suitable instrumentation require an enhanced modelling effort and modern kinetic parameter estimation strategies. The present work is dedicated to nonlinear dynamic modelling and parameter estimation for a mammalian cell culture process used for mAb production. By using a dynamical model of such kind of processes, an optimization-based technique for estimation of kinetic parameters in the model of mammalian cell culture process is developed. The estimation is achieved as a result of minimizing an error function by a particle swarm optimization (PSO) algorithm. The proposed estimation approach is analyzed in this work by using a particular model of mammalian cell culture, as a case study, but is generic for this class of bioprocesses. The presented case study shows that the proposed parameter estimation technique provides a more accurate simulation of the experimentally observed process behaviour than reported in previous studies. PMID:25685797

  20. Effects of process parameters in plastic, metal, and ceramic injection molding processes

    NASA Astrophysics Data System (ADS)

    Lee, Shi W.; Ahn, Seokyoung; Whang, Chul Jin; Park, Seong Jin; Atre, Sundar V.; Kim, Jookwon; German, Randall M.

    2011-09-01

    Plastic injection molding has been widely used in the past and is a dominant forming approach today. As the customer demands require materials with better engineering properties that were not feasible with polymers, powder injection molding with metal and ceramic powders has received considerable attention in recent decades. To better understand the differences in the plastic injection molding, metal injection molding, and ceramic injection molding, the effects of the core process parameters on the process performances has been studied using the state-of-the-art computer-aided engineering (CAE) design tool, PIMSolver® The design of experiments has been conducted using the Taguchi method to obtain the relative contributions of various process parameters onto the successful operations.

  1. Technical bases for precipitate hydrolysis process operating parameters

    SciTech Connect

    Bannochie, C.J.

    1992-10-05

    This report provides the experimental data and rationale in support of the operating parameters for precipitate hydrolysis specified in WSRC-RP-92737. The report is divided into two sections, the first dealing with lab-scale precipitate hydrolysis experimentation while the second part addresses large-scale runs conducted to demonstrate the revised operating parameters in the Precipitate Hydrolysis Experimental Facility (PHEF).

  2. Development of AACAP practice parameters for gender nonconformity and gender discordance in children and adolescents.

    PubMed

    Adelson, Stewart L

    2011-10-01

    The American Academy of Child and Adolescent Psychiatry (AACAP) is preparing a publication, Practice Parameter on Gay, Lesbian or Bisexual Sexual Orientation, Gender-Nonconformity, and Gender Discordance in Children and Adolescents. This article discusses the development of the part of the parameter related to gender nonconformity and gender discordance and describes the practice parameter preparation process,rationale, key scientific evidence, and methodology. Also discussed are terminology considerations, related clinical issues and practice skills, and overall organization of information including influences on gender development, gender role behavior, gender nonconformity and gender discordance, and their relationship to the development of sexual orientation. PMID:22051003

  3. Software Development Standard Processes (SDSP)

    NASA Technical Reports Server (NTRS)

    Lavin, Milton L.; Wang, James J.; Morillo, Ronald; Mayer, John T.; Jamshidian, Barzia; Shimizu, Kenneth J.; Wilkinson, Belinda M.; Hihn, Jairus M.; Borgen, Rosana B.; Meyer, Kenneth N.; Crean, Kathleen A.; Rinker, George C.; Smith, Thomas P.; Lum, Karen T.; Hanna, Robert A.; Erickson, Daniel E.; Gamble, Edward B., Jr.; Morgan, Scott C.; Kelsay, Michael G.; Newport, Brian J.; Lewicki, Scott A.; Stipanuk, Jeane G.; Cooper, Tonja M.; Meshkat, Leila

    2011-01-01

    A JPL-created set of standard processes is to be used throughout the lifecycle of software development. These SDSPs cover a range of activities, from management and engineering activities, to assurance and support activities. These processes must be applied to software tasks per a prescribed set of procedures. JPL s Software Quality Improvement Project is currently working at the behest of the JPL Software Process Owner to ensure that all applicable software tasks follow these procedures. The SDSPs are captured as a set of 22 standards in JPL s software process domain. They were developed in-house at JPL by a number of Subject Matter Experts (SMEs) residing primarily within the Engineering and Science Directorate, but also from the Business Operations Directorate and Safety and Mission Success Directorate. These practices include not only currently performed best practices, but also JPL-desired future practices in key thrust areas like software architecting and software reuse analysis. Additionally, these SDSPs conform to many standards and requirements to which JPL projects are beholden.

  4. Optimized process parameters for fabricating metal particles reinforced 5083 Al composite by friction stir processing.

    PubMed

    Bauri, Ranjit; Yadav, Devinder; Shyam Kumar, C N; Janaki Ram, G D

    2015-12-01

    Metal matrix composites (MMCs) exhibit improved strength but suffer from low ductility. Metal particles reinforcement can be an alternative to retain the ductility in MMCs (Bauri and Yadav, 2010; Thakur and Gupta, 2007) [1,2]. However, processing such composites by conventional routes is difficult. The data presented here relates to friction stir processing (FSP) that was used to process metal particles reinforced aluminum matrix composites. The data is the processing parameters, rotation and traverse speeds, which were optimized to incorporate Ni particles. A wide range of parameters covering tool rotation speeds from 1000 rpm to 1800 rpm and a range of traverse speeds from 6 mm/min to 24 mm/min were explored in order to get a defect free stir zone and uniform distribution of particles. The right combination of rotation and traverse speed was found from these experiments. Both as-received coarse particles (70 μm) and ball-milled finer particles (10 μm) were incorporated in the Al matrix using the optimized parameters. PMID:26566541

  5. Optimized process parameters for fabricating metal particles reinforced 5083 Al composite by friction stir processing

    PubMed Central

    Bauri, Ranjit; Yadav, Devinder; Shyam Kumar, C.N.; Janaki Ram, G.D.

    2015-01-01

    Metal matrix composites (MMCs) exhibit improved strength but suffer from low ductility. Metal particles reinforcement can be an alternative to retain the ductility in MMCs (Bauri and Yadav, 2010; Thakur and Gupta, 2007) [1,2]. However, processing such composites by conventional routes is difficult. The data presented here relates to friction stir processing (FSP) that was used to process metal particles reinforced aluminum matrix composites. The data is the processing parameters, rotation and traverse speeds, which were optimized to incorporate Ni particles. A wide range of parameters covering tool rotation speeds from 1000 rpm to 1800 rpm and a range of traverse speeds from 6 mm/min to 24 mm/min were explored in order to get a defect free stir zone and uniform distribution of particles. The right combination of rotation and traverse speed was found from these experiments. Both as-received coarse particles (70 μm) and ball-milled finer particles (10 μm) were incorporated in the Al matrix using the optimized parameters. PMID:26566541

  6. Experiments for practical education in process parameter optimization for selective laser sintering to increase workpiece quality

    NASA Astrophysics Data System (ADS)

    Reutterer, Bernd; Traxler, Lukas; Bayer, Natascha; Drauschke, Andreas

    2016-04-01

    Selective Laser Sintering (SLS) is considered as one of the most important additive manufacturing processes due to component stability and its broad range of usable materials. However the influence of the different process parameters on mechanical workpiece properties is still poorly studied, leading to the fact that further optimization is necessary to increase workpiece quality. In order to investigate the impact of various process parameters, laboratory experiments are implemented to improve the understanding of the SLS limitations and advantages on an educational level. Experiments are based on two different workstations, used to teach students the fundamentals of SLS. First of all a 50 W CO2 laser workstation is used to investigate the interaction of the laser beam with the used material in accordance with varied process parameters to analyze a single-layered test piece. Second of all the FORMIGA P110 laser sintering system from EOS is used to print different 3D test pieces in dependence on various process parameters. Finally quality attributes are tested including warpage, dimension accuracy or tensile strength. For dimension measurements and evaluation of the surface structure a telecentric lens in combination with a camera is used. A tensile test machine allows testing of the tensile strength and the interpreting of stress-strain curves. The developed laboratory experiments are suitable to teach students the influence of processing parameters. In this context they will be able to optimize the input parameters depending on the component which has to be manufactured and to increase the overall quality of the final workpiece.

  7. Technology development life cycle processes.

    SciTech Connect

    Beck, David Franklin

    2013-05-01

    This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81 of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.

  8. Processes and process development in Taiwan

    NASA Technical Reports Server (NTRS)

    Hwang, H. L.

    1986-01-01

    Silicon material research in the Republic of China (ROC) parallels its development in the electronic industry. A brief outline of the historical development in ROC silicon material research is given. Emphasis is placed on the recent Silane Project managed by the National Science Council, ROC, including project objectives, task forces, and recent accomplishments. An introduction is also given to industrialization of the key technologies developed in this project.

  9. Dependence of 20-nm C/H CD windows on critical process parameters

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Su; Gu, Pei-Yi; Tsai, Ming-Jinn

    2010-04-01

    20 nm contact hole (C/H) patterning is applicable for sub-22 nm technology node applications. Dependence of C/H CD window on critical process parameters is important for process stability and repeatability. Post applied baking (PAB) condition, resist thickness, develop time, and dry etch rate are considered to be the most important process parameters for e-beam chain scission resist ZEP520A C/H patterning. In this paper, PAB temperatures (TPAB) are investigated at temperatures between lower than glass transition temperature (TG) and much higher than TF. Effects of these process parameters on 20 nm +/-10% C/H CD window for various pattern densities and e-beam doses are studied. The critical process parameters are determined by their effects on CD window size, C/H sidewall profile, proximity effect immunity, ΔCD/ΔDose slope, and etch selectivity. Experimental results are summarized below. Thinnest ZEP520A film has the largest 20nm +/-10% CD window on D-D plot for various L/S ratios and doses. The dosage window of smaller C/H CD is larger. The proximity effect is negligible for 50 nm ZEP520A baked at 200°C/300 sec. No apparent effect is found in CD window on D-D plot for develop time as short as 30 sec. PAB condition is most critical than the other process parameters in determining resist density and polymerization which affect e-beam scattering and chain scission in resist film and therefore affects CD resolution and window. PAB condition of 140°C/60 sec is most desirable in terms of CD window on D-D plot, C/H sidewall profile, dry etch rate and proximity effect.

  10. Optimisation of Shape Parameters and Process Manufacturing for an Automotive Safety Part

    NASA Astrophysics Data System (ADS)

    Gildemyn, Eric; Dal Santo, Philippe; Potiron, Alain; Saïdane, Delphine

    2007-05-01

    In recent years, the weight and the cost of automotive vehicles have considerably increased due to the importance devoted to safety systems. It is therefore necessary to reduce the weight and the production cost of components by improving their shape and manufacturing process. This work deals with a numerical approach for optimizing the manufacturing process parameters of a safety belt anchor using a genetic algorithm (NSGA II). This type of component is typically manufactured in three stages: blanking, rounding of the edges by punching and finally, bending with a 90° angle. In this study, only the rounding and the bending will be treated. The numerical model is linked to the genetic algorithm in order to optimize the process parameters. This is implemented by using ABAQUSscript files developed in the Python programming language. The algorithm modifies the script files and restarts the FEM analysis automatically. Lemaitre's damage model is introduced in the material behaviour laws and implemented in the FEM analysis by using a FORTRAN subroutine. The influence of two process parameters (die radius and the rounding punch radius) and five shape parameters were investigated. The objective functions are (i) the material damage state at the end of the forming process, (ii) the stress field and (iii) the maximum Von Mises stress in the folded zone.

  11. Technical bases for precipitate hydrolysis process operating parameters

    SciTech Connect

    Bannochie, C.J.; Lambert, D.P.

    1992-11-09

    This report provides the experimental data and rationale in support of the operating parameters for tetraphenylborate precipitate hydrolysis specified in WSRC-RP-92-737. The report is divided into two sections, the first dealing with lab-scale precipitate hydrolysis experimentation while the second part addresses large-scale runs conducted to demonstrate the revised operating parameters in the Precipitate Hydrolysis Experimental Facility (PHEF). The program was in conjunction with reducing the nitrite ion level in DWPF feed.

  12. Technical bases for precipitate hydrolysis process operating parameters. Revision 1

    SciTech Connect

    Bannochie, C.J.; Lambert, D.P.

    1992-11-09

    This report provides the experimental data and rationale in support of the operating parameters for tetraphenylborate precipitate hydrolysis specified in WSRC-RP-92-737. The report is divided into two sections, the first dealing with lab-scale precipitate hydrolysis experimentation while the second part addresses large-scale runs conducted to demonstrate the revised operating parameters in the Precipitate Hydrolysis Experimental Facility (PHEF). The program was in conjunction with reducing the nitrite ion level in DWPF feed.

  13. Influence of Process Parameter on Grit Blasting as a Pretreatment Process for Thermal Spraying

    NASA Astrophysics Data System (ADS)

    Bobzin, K.; Öte, M.; Linke, T. F.; Sommer, J.; Liao, X.

    2016-01-01

    In thermal spraying, uncoated substrates usually require roughening. As the most common roughening method, grit blasting increases the surface area and produces undercuts in almost all cases, which facilitate mechanical interlocking and thus promote the bonding between the substrate and coating. The effects of grit blasting parameters, i.e., the particle size, the blasting angle, the stand-off distance, and the pressure, on the resulting surface topography are investigated. Furthermore, the efficiency and wear behavior of the blasting media are analyzed. Influences of three different blasting media, corundum, alumina zirconia, and steel shot, on the surface roughening, are compared. By varying adjusted blasting parameters, different initial conditions (surface topography) are created. Subsequently, the substrate is coated, and the coating bond strength is measured. One of the main results of this publication is that alumina zirconia and steel grit show a longer lifetime than pure alumina as a blasting media. Moreover, it has been shown that the blasting parameters such as grain size, working pressure, and history (wear status) of the abrasive particles have a significant effect on the resulting surface topography. Additionally, systematical analysis in this study shows that the blasting parameters such as stand-off distance and blasting angle have a small influence on the results of the blasting process. Another important conclusion of this study is that the conventional surface parameters that have been analyzed in this study did not turn out to be suitable for describing the relationship between the surface topography of the substrate and resulting bond strength.

  14. Development of a Three-Dimensional Heat-Transfer Model for the Gas Tungsten Arc Welding Process Using the Finite Element Method Coupled with a Genetic Algorithm Based Identification of Uncertain Input Parameters

    NASA Astrophysics Data System (ADS)

    Bag, S.; de, A.

    2008-11-01

    An accurate estimation of the temperature field in weld pool and its surrounding area is important for a priori determination of the weld-pool dimensions and the weld thermal cycles. A finite element based three-dimensional (3-D) quasi-steady heat-transfer model is developed in the present work to compute temperature field in gas tungsten arc welding (GTAW) process. The numerical model considers temperature-dependent material properties and latent heat of melting and solidification. A novelty of the numerical model is that the welding heat source is considered in the form of an adaptive volumetric heat source that confirms to the size and the shape of the weld pool. The need to predefine the dimensions of the volumetric heat source is thus overcome. The numerical model is further integrated with a parent-centric recombination (PCX) operated generalized generation gap (G3) model based genetic algorithm to identify the magnitudes of process efficiency and arc radius that are usually unknown but required for the accurate estimation of the net heat input into the workpiece. The complete numerical model and the genetic algorithm based optimization code are developed indigenously using an Intel Fortran Compiler. The integrated model is validated further with a number of experimentally measured weld dimensions in GTA-welded samples in stainless steels.

  15. A preliminary evaluation of an F100 engine parameter estimation process using flight data

    NASA Technical Reports Server (NTRS)

    Maine, Trindel A.; Gilyard, Glenn B.; Lambert, Heather H.

    1990-01-01

    The parameter estimation algorithm developed for the F100 engine is described. The algorithm is a two-step process. The first step consists of a Kalman filter estimation of five deterioration parameters, which model the off-nominal behavior of the engine during flight. The second step is based on a simplified steady-state model of the 'compact engine model' (CEM). In this step the control vector in the CEM is augmented by the deterioration parameters estimated in the first step. The results of an evaluation made using flight data from the F-15 aircraft are presented, indicating that the algorithm can provide reasonable estimates of engine variables for an advanced propulsion-control-law development.

  16. A preliminary evaluation of an F100 engine parameter estimation process using flight data

    NASA Technical Reports Server (NTRS)

    Maine, Trindel A.; Gilyard, Glenn B.; Lambert, Heather H.

    1990-01-01

    The parameter estimation algorithm developed for the F100 engine is described. The algorithm is a two-step process. The first step consists of a Kalman filter estimation of five deterioration parameters, which model the off-nominal behavior of the engine during flight. The second step is based on a simplified steady-state model of the compact engine model (CEM). In this step, the control vector in the CEM is augmented by the deterioration parameters estimated in the first step. The results of an evaluation made using flight data from the F-15 aircraft are presented, indicating that the algorithm can provide reasonable estimates of engine variables for an advanced propulsion control law development.

  17. Sensor Data Acquisition and Processing Parameters for Human Activity Classification

    PubMed Central

    Bersch, Sebastian D.; Azzi, Djamel; Khusainov, Rinat; Achumba, Ifeyinwa E.; Ries, Jana

    2014-01-01

    It is known that parameter selection for data sampling frequency and segmentation techniques (including different methods and window sizes) has an impact on the classification accuracy. For Ambient Assisted Living (AAL), no clear information to select these parameters exists, hence a wide variety and inconsistency across today's literature is observed. This paper presents the empirical investigation of different data sampling rates, segmentation techniques and segmentation window sizes and their effect on the accuracy of Activity of Daily Living (ADL) event classification and computational load for two different accelerometer sensor datasets. The study is conducted using an ANalysis Of VAriance (ANOVA) based on 32 different window sizes, three different segmentation algorithm (with and without overlap, totaling in six different parameters) and six sampling frequencies for nine common classification algorithms. The classification accuracy is based on a feature vector consisting of Root Mean Square (RMS), Mean, Signal Magnitude Area (SMA), Signal Vector Magnitude (here SMV), Energy, Entropy, FFTPeak, Standard Deviation (STD). The results are presented alongside recommendations for the parameter selection on the basis of the best performing parameter combinations that are identified by means of the corresponding Pareto curve. PMID:24599189

  18. Estimation of Temperature Dependent Parameters of a Batch Alcoholic Fermentation Process

    NASA Astrophysics Data System (ADS)

    de Andrade, Rafael Ramos; Rivera, Elmer Ccopa; Costa, Aline C.; Atala, Daniel I. P.; Filho, Francisco Maugeri; Filho, Rubens Maciel

    In this work, a procedure was established to develop a mathematical model considering the effect of temperature on reaction kinetics. Experiments were performed in batch mode in temperatures from 30 to 38°C. The microorganism used was Saccharomyces cerevisiae and the culture media, sugarcane molasses. The objective is to assess the difficulty in updating the kinetic parameters when there are changes in fermentation conditions. We conclude that, although the re-estimation is a time-consuming task, it is possible to accurately describe the process when there are changes in raw material composition if a re-estimation of parameters is performed.

  19. Development of mild gasification process

    SciTech Connect

    Chu, C.I.C.; Derting, T.M.

    1988-07-01

    Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.

  20. Development of mild gasification process

    SciTech Connect

    Chu, C.I.C.; Gillespie, B.L.

    1988-02-01

    Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. DE-AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1-Test Plan; Task 2-Optimization of Mild Gasification Process; Task 3-Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4-Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.

  1. Development of mild gasification process

    SciTech Connect

    Chu, C.I.C.; Williams, S.W.

    1989-01-01

    Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.

  2. Development of mild gasification process

    SciTech Connect

    Chu, C.I.C.; Gillespie, B.L.

    1987-11-01

    Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.

  3. Control of Groundwater Remediation Process as Distributed Parameter System

    NASA Astrophysics Data System (ADS)

    Mendel, M.; Kovács, T.; Hulkó, G.

    2014-12-01

    Pollution of groundwater requires the implementation of appropriate solutions which can be deployed for several years. The case of local groundwater contamination and its subsequent spread may result in contamination of drinking water sources or other disasters. This publication aims to design and demonstrate control of pumping wells for a model task of groundwater remediation. The task consists of appropriately spaced soil with input parameters, pumping wells and control system. Model of controlled system is made in the program MODFLOW using the finitedifference method as distributed parameter system. Control problem is solved by DPS Blockset for MATLAB & Simulink.

  4. A Novel Scale Up Model for Prediction of Pharmaceutical Film Coating Process Parameters.

    PubMed

    Suzuki, Yasuhiro; Suzuki, Tatsuya; Minami, Hidemi; Terada, Katsuhide

    2016-01-01

    In the pharmaceutical tablet film coating process, we clarified that a difference in exhaust air relative humidity can be used to detect differences in process parameters values, the relative humidity of exhaust air was different under different atmospheric air humidity conditions even though all setting values of the manufacturing process parameters were the same, and the water content of tablets was correlated with the exhaust air relative humidity. Based on this experimental data, the exhaust air relative humidity index (EHI), which is an empirical equation that includes as functional parameters the pan coater type, heated air flow rate, spray rate of coating suspension, saturated water vapor pressure at heated air temperature, and partial water vapor pressure at atmospheric air pressure, was developed. The predictive values of exhaust relative humidity using EHI were in good correlation with the experimental data (correlation coefficient of 0.966) in all datasets. EHI was verified using the date of seven different drug products of different manufacturing scales. The EHI model will support formulation researchers by enabling them to set film coating process parameters when the batch size or pan coater type changes, and without the time and expense of further extensive testing. PMID:26936048

  5. Fault detection in heavy duty wheels by advanced vibration processing techniques and lumped parameter modeling

    NASA Astrophysics Data System (ADS)

    Malago`, M.; Mucchi, E.; Dalpiaz, G.

    2016-03-01

    Heavy duty wheels are used in applications such as automatic vehicles and are mainly composed of a polyurethane tread glued to a cast iron hub. In the manufacturing process, the adhesive application between tread and hub is a critical assembly phase, since it is completely made by an operator and a contamination of the bond area may happen. Furthermore, the presence of rust on the hub surface can contribute to worsen the adherence interface, reducing the operating life. In this scenario, a quality control procedure for fault detection to be used at the end of the manufacturing process has been developed. This procedure is based on vibration processing techniques and takes advantages of the results of a lumped parameter model. Indicators based on cyclostationarity can be considered as key parameters to be adopted in a monitoring test station at the end of the production line due to their not deterministic characteristics.

  6. Application of CBR method for adding the process of cutting tools and parameters selection

    NASA Astrophysics Data System (ADS)

    Ociepka, P.; Herbus, K.

    2015-11-01

    Modem enterprises must face with the dynamically changing market demand what influences the designing process. It is possible by linking computer tools with information gathered by experienced designers teams. The article describes the method basing on engineering knowledge and experience to adding the process of tools selection and cutting parameters determination for a turning operation. The method, proposed by the authors, is based on the CBR (Case Based Reasoning) method. CBR is a method of problem solving that involves searching for an analogy (similarity) between the current task to be solved, and the earlier cases that properly described, are stored in a computer memory. This article presents an algorithm and a formalized description of the developed method. It was discussed the range of its utilization, as well as it was illustrated the method of its functioning on the example of the tools and cutting parameters selection with respect to the turning process.

  7. Development of the selective coagulation process

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1992-07-01

    The selective hydrophobic coagulation (SHC) process is based on the recent finding that hydrophobic particles can be selectively coagulated without using traditional agglomerating agents or flocculants. The driving force for the coagulation is the attractive energy between hydrophobic surfaces, an interaction that has been overlooked in classical colloid chemistry. In most cases, selective separations can be achieved using simple pH control to disperse the mineral matter, followed by recovery of the coal coagula using techniques that take advantage of the size enlargement. In the present work, studies have been carried out to further investigate the fundamental mechanisms of the SHC process and the parameters that affect the process of separating coal from the ash-forming minerals and pyritic sulfur. Studies have included direct force measurements of the attractive interaction between model hydrophobic surfaces, in-situ measurements of the size distributions of coagula formed under a variety of operating conditions, and development of a population balance model to describe the coagulation process. An extended DLVO colloid stability model which includes a hydrophobic interaction energy term has also been developed to explain the findings obtained from the experimental studies. In addition to the fundamental studies, bench-scale process development test work has been performed to establish the best possible method of separating the coagula from dispersed mineral matter. Two types of separators, i.e., a sedimentation tank and a rotating drum screen, were examined in this study. The sedimentation tank proved to be the more efficient unit, achieving ash reductions as high as 60% in a single pass while recovering more than 90% of the combustible material. This device, which minimizes turbulence and coagula breakage, was used in subsequent test work to optimize design and operating parameters.

  8. Process Development for Nanostructured Photovoltaics

    SciTech Connect

    Elam, Jeffrey W.

    2015-01-01

    Photovoltaic manufacturing is an emerging industry that promises a carbon-free, nearly limitless source of energy for our nation. However, the high-temperature manufacturing processes used for conventional silicon-based photovoltaics are extremely energy-intensive and expensive. This high cost imposes a critical barrier to the widespread implementation of photovoltaic technology. Argonne National Laboratory and its partners recently invented new methods for manufacturing nanostructured photovoltaic devices that allow dramatic savings in materials, process energy, and cost. These methods are based on atomic layer deposition, a thin film synthesis technique that has been commercialized for the mass production of semiconductor microelectronics. The goal of this project was to develop these low-cost fabrication methods for the high efficiency production of nanostructured photovoltaics, and to demonstrate these methods in solar cell manufacturing. We achieved this goal in two ways: 1) we demonstrated the benefits of these coatings in the laboratory by scaling-up the fabrication of low-cost dye sensitized solar cells; 2) we used our coating technology to reduce the manufacturing cost of solar cells under development by our industrial partners.

  9. online Surveillance of Industrial Processes with Correlated Parameters

    Energy Science and Technology Software Center (ESTSC)

    1996-12-18

    SMP is a system for online surveillance of industrial processes or machinery for determination of the incipience or onset of abnormal operating conditions. SMP exploits the cross correlation between all of the sensors that are available on the system under surveillance to provide an extremely high sensitivity for annunciation of subtle disturbances in process variables.

  10. Parameter identification of process simulation models as a means for knowledge acquisition and technology transfer

    NASA Astrophysics Data System (ADS)

    Batzias, Dimitris F.; Ifanti, Konstantina

    2012-12-01

    Process simulation models are usually empirical, therefore there is an inherent difficulty in serving as carriers for knowledge acquisition and technology transfer, since their parameters have no physical meaning to facilitate verification of the dependence on the production conditions; in such a case, a 'black box' regression model or a neural network might be used to simply connect input-output characteristics. In several cases, scientific/mechanismic models may be proved valid, in which case parameter identification is required to find out the independent/explanatory variables and parameters, which each parameter depends on. This is a difficult task, since the phenomenological level at which each parameter is defined is different. In this paper, we have developed a methodological framework under the form of an algorithmic procedure to solve this problem. The main parts of this procedure are: (i) stratification of relevant knowledge in discrete layers immediately adjacent to the layer that the initial model under investigation belongs to, (ii) design of the ontology corresponding to these layers, (iii) elimination of the less relevant parts of the ontology by thinning, (iv) retrieval of the stronger interrelations between the remaining nodes within the revised ontological network, and (v) parameter identification taking into account the most influential interrelations revealed in (iv). The functionality of this methodology is demonstrated by quoting two representative case examples on wastewater treatment.

  11. Simulation of Electromagnetic and Thermal Processes in Fastcycling Magnets for Calculation Parameters of Stability

    NASA Astrophysics Data System (ADS)

    Zubko, V.; Kozub, S.; Tkachenko, L.

    SIS300 fast-cycling superconducting quadrupole magnet is developed at IHEP. Temperature margin and minimum quench energy are main parameters of stability of superconducting magnets. These parameters are important for the design and safe operation of superconducting magnets. But additional understanding for fast-cycling superconducting magnets is needed. To calculate the temperature margin one needs coupled numerical transient simulation of electromagnetic and thermal processes in the coil because critical temperature, operating temperature and AC losses are nonuniform over turns and their magnitudes vary in time during accelerator cycles. For calculation of the minimum quench energy the combination of the network model with thermal analysis is necessary, which allows one to model quench dynamics, including the effects of a current redistribution between strands of cable and spatial inhomogeneity of cable. Results for the temperature margin and the minimum quench energy for the magnet are presented and theirs dependence on various parameters is discussed.

  12. Subsonic flight test evaluation of a propulsion system parameter estimation process for the F100 engine

    NASA Technical Reports Server (NTRS)

    Orme, John S.; Gilyard, Glenn B.

    1992-01-01

    Integrated engine-airframe optimal control technology may significantly improve aircraft performance. This technology requires a reliable and accurate parameter estimator to predict unmeasured variables. To develop this technology base, NASA Dryden Flight Research Facility (Edwards, CA), McDonnell Aircraft Company (St. Louis, MO), and Pratt & Whitney (West Palm Beach, FL) have developed and flight-tested an adaptive performance seeking control system which optimizes the quasi-steady-state performance of the F-15 propulsion system. This paper presents flight and ground test evaluations of the propulsion system parameter estimation process used by the performance seeking control system. The estimator consists of a compact propulsion system model and an extended Kalman filter. The extended Laman filter estimates five engine component deviation parameters from measured inputs. The compact model uses measurements and Kalman-filter estimates as inputs to predict unmeasured propulsion parameters such as net propulsive force and fan stall margin. The ability to track trends and estimate absolute values of propulsion system parameters was demonstrated. For example, thrust stand results show a good correlation, especially in trends, between the performance seeking control estimated and measured thrust.

  13. Effect of processes and processing parameters on 3-D braided preforms for composites

    SciTech Connect

    Li, W.; Shiekh, A.E.

    1988-07-01

    A general comparison about the processes, the structures and tensile properties of two 3-D braiding techniques are presented in this paper. The yarn orientation, braid width, braider curvature at fabric surface, and yarn volume fraction of both the 4-step and 2-step braids are analytically predicted in terms of the normalized cycle length which is directly related to the machine operating conditions. The extreme values of the parameters are discussed and compared. Results of the tensile properties of the braids are presented and discussed in terms of the structure differences. 11 references, 9 figures, 1 table.

  14. Identification of sorption processes and parameters for radionuclide transport in fractured rock

    NASA Astrophysics Data System (ADS)

    Dai, Zhenxue; Wolfsberg, Andrew; Reimus, Paul; Deng, Hailin; Kwicklis, Edward; Ding, Mei; Ware, Doug; Ye, Ming

    2012-01-01

    SummaryIdentification of chemical reaction processes in subsurface environments is a key issue for reactive transport modeling because simulating different processes requires developing different chemical-mathematical models. In this paper, two sorption processes (equilibrium and kinetics) are considered for modeling neptunium and uranium sorption in fractured rock. Based on different conceptualizations of the two processes occurring in fracture and/or matrix media, seven dual-porosity, multi-component reactive transport models are developed. The process models are identified with a stepwise strategy by using multi-tracer concentration data obtained from a series of transport experiments. In the first step, breakthrough data of a conservative tracer (tritium) obtained from four experiments are used to estimate the flow and non-reactive transport parameters (i.e., mean fluid residence time in fracture, fracture aperture, and matrix tortuosity) common to all the reactive transport models. In the second and third steps, by fixing the common non-reactive flow and transport parameters, the sorption parameters (retardation factor, sorption coefficient, and kinetic rate constant) of each model are estimated using the breakthrough data of reactive tracers, neptunium and uranium, respectively. Based on the inverse modeling results, the seven sorption-process models are discriminated using four model discrimination (or selection) criteria, Akaike information criterion ( AIC), modified Akaike information criterion ( AICc), Bayesian information criterion ( BIC) and Kashyap information criterion ( KIC). These criteria suggest the kinetic sorption process for modeling reactive transport of neptunium and uranium transport in both fracture and matrix. This conclusion is confirmed by two chemical criteria, the half reaction time and Damköhler number criterion.

  15. Effect of some process parameters in enzymatic dyeing of wool.

    PubMed

    Tzanov, Tzanko; Silva, Carla Joana; Zille, Andrea; Oliveira, Jovita; Cavaco-Paulo, Artur

    2003-10-01

    This article reports on the dyeing of wool using an enzymatic system comprising laccase; dye precursor, 2,5-diaminobenzenesulfonic acid; and dye modifiers, catechol and resorcinol. Enzymatic dyeing was performed as a batchwise process at the temperature and pH of maximum enzyme activity. The effects of the process variables reaction time, enzyme, and modifier concentration on fabric color were studied, according to an appropriate experimental design. Different hues and depths of shades could be achieved by varying the concentration of the modifiers and the time of laccase treatment. The duration of the enzymatic reaction appeared to be the most important factor in the dyeing process. Thus, the dyeing process, performed at low temperature and mild pH, was advantageous in terms of reduced enzyme and chemical dosage. PMID:14566065

  16. Signal processing for longitudinal parameters of the Tevatron beam

    SciTech Connect

    Pordes, S.; Crisp, J.; Fellenz, B.; Flora, R.; Para, A.; Tollestrup, A.V.; /Fermilab

    2005-05-01

    We describe the system known as the Tevatron SBD [1] which is used to provide information on the longitudinal parameters of coalesced beam bunches in the Tevatron. The system has been upgraded over the past year with a new digitizer and improved software. The quantities provided for each proton and antiproton bunch include the intensity, the longitudinal bunch profile, the timing of the bunch with respect to the low-level RF, the momentum spread and the longitudinal emittance. The system is capable of 2 Hz operation and is run at 1 Hz.

  17. Metallic Fuel Casting Development and Parameter Optimization Simulations

    SciTech Connect

    R.S. Fielding; J. Crapps; C. Unal; J.R. Kennedy

    2013-03-01

    One of the advantages of metallic fuel is the abilility to cast the fuel slugs to near net shape with little additional processing. However, the high aspect ratio of the fuel is not ideal for casting. EBR-II fuel was cast using counter gravity injection casting (CGIC) but, concerns have been raised concerning the feasibility of this process for americium bearing alloys. The Fuel Cycle Research and Development program has begun developing gravity casting techniques suitable for fuel production. Compared to CGIC gravity casting does not require a large heel that then is recycled, does not require application of a vacuum during melting, and is conducive to re-usable molds. Development has included fabrication of two separate benchscale, approximately 300 grams, systems. To shorten development time computer simulations have been used to ensure mold and crucible designs are feasible and to identify which fluid properties most affect casting behavior and therefore require more characterization.

  18. Development of force field parameters for molecular simulation of polylactide

    PubMed Central

    McAliley, James H.; Bruce, David A.

    2011-01-01

    Polylactide is a biodegradable polymer that is widely used for biomedical applications, and it is a replacement for some petroleum based polymers in applications that range from packaging to carpeting. Efforts to characterize and further enhance polylactide based systems using molecular simulations have to this point been hindered by the lack of accurate atomistic models for the polymer. Thus, we present force field parameters specifically suited for molecular modeling of PLA. The model, which we refer to as PLAFF3, is based on a combination of the OPLS and CHARMM force fields, with modifications to bonded and nonbonded parameters. Dihedral angle parameters were adjusted to reproduce DFT data using newly developed CMAP dihedral cross terms, and the model was further adjusted to reproduce experimentally resolved crystal structure conformations, melt density, volume expansivity, and the glass transition temperature of PLA. We recommend the use of PLAFF3 in modeling PLA in its crystalline or amorphous states and have provided the necessary input files required for the publicly available molecular dynamics code GROMACS. PMID:22180734

  19. Cavity parameters identification for TESLA control system development

    NASA Astrophysics Data System (ADS)

    Czarski, Tomasz; Pozniak, Krysztof T.; Romaniuk, Ryszard S.; Simrock, Stefan

    2005-08-01

    Aim of the control system development for TESLA cavity is a more efficient stabilization of the pulsed, accelerating EM field inside resonator. Cavity parameters identification is an essential task for the comprehensive control algorithm. TESLA cavity simulator has been successfully implemented using high-speed FPGA technology. Electromechanical model of the cavity resonator includes Lorentz force detuning and beam loading. The parameters identification is based on the electrical model of the cavity. The model is represented by state space equation for envelope of the cavity voltage driven by current generator and beam loading. For a given model structure, the over-determined matrix equation is created covering long enough measurement range with the solution according to the least-squares method. A low-degree polynomial approximation is applied to estimate the time-varying cavity detuning during the pulse. The measurement channel distortion is considered, leading to the external cavity model seen by the controller. The comprehensive algorithm of the cavity parameters identification was implemented in the Matlab system with different modes of operation. Some experimental results were presented for different cavity operational conditions. The following considerations have lead to the synthesis of the efficient algorithm for the cavity control system predicted for the potential FPGA technology implementation.

  20. DEVELOPMENT OF VADOSE-ZONE HYDRAULIC PARAMETER VALUES

    SciTech Connect

    ROGERS PM

    2008-01-21

    Several approaches have been developed to establish a relation between the soil-moisture retention curve and readily available soil properties. Those relationships are referred to as pedotransfer functions. Described in this paper are the rationale, approach, and corroboration for use of a nonparametric pedotransfer function for the estimation of soil hydraulic-parameter values at the yucca Mountain area in Nevada for simulations of net infiltration. This approach, shown to be applicable for use at Yucca Mountain, is also applicable for use at the Hanford Site where the underlying data were collected.

  1. Applying an interferometric exposure model to analyze the influences of process parameters on the linewidth

    NASA Astrophysics Data System (ADS)

    Chien, Cheng-Wei; Chen, Jyh-Chen; Lee, Ju-Yi

    2006-11-01

    We utilize a modified interferometric exposure model, enhanced with the Beer-Lambert law, to study how some process parameters influence the structural dimensions within the whole exposure area. An experimental apparatus is built to verify the accuracy of this model. The simulation results indicate that when the incident angle is larger than 15°, the effect of the beam deformation cannot be neglected. One cannot readily obtain periodic structures with the same dimensions during static exposure because of the Gaussian distribution of the light intensity. The theoretical results match the experimental ones quite well. The variation of Dill's parameter A has a greater influence on the transmittance and the linewidth when A is decreasing. If a poor contrast fringe is exposed in the photoresist, it will not only cause a greater nonuniformity of the structural dimensions but also a decreased aspect ratio in the structure after the development process.

  2. FRETView: a computer program to simplify the process of obtaining fluorescence resonance energy transfer parameters.

    PubMed

    Stevens, Nathan; Dyer, Joanne; Martí, Angel A; Solomon, Marissa; Turro, Nicholas J

    2007-08-01

    The process of modeling the fluorescence resonance energy transfer (FRET) process for a donor-acceptor pair can be rather challenging, yet few computer programs exist that allow such modeling to be done with relative ease. In order to address this, we have developed a Java-based program, FRETView, which allows numerous FRET parameters to be obtained with just a few mouse clicks. Being a Java-based program, it runs equally well on all the major operating systems such as Windows, Mac OS X, Linux, Solaris. The program allows the user to effortlessly input pertinent information about the donor-acceptor pair, including the absorption and/or emission spectra, and outputs the calculated FRET parameters in table format, as well as graphical plots. PMID:17668122

  3. Implant for in-vivo parameter monitoring, processing and transmitting

    SciTech Connect

    Ericson, Milton N.; McKnight, Timothy E.; Smith, Stephen F.; Hylton, James O.

    2009-11-24

    The present invention relates to a completely implantable intracranial pressure monitor, which can couple to existing fluid shunting systems as well as other internal monitoring probes. The implant sensor produces an analog data signal which is then converted electronically to a digital pulse by generation of a spreading code signal and then transmitted to a location outside the patient by a radio-frequency transmitter to an external receiver. The implanted device can receive power from an internal source as well as an inductive external source. Remote control of the implant is also provided by a control receiver which passes commands from an external source to the implant system logic. Alarm parameters can be programmed into the device which are capable of producing an audible or visual alarm signal. The utility of the monitor can be greatly expanded by using multiple pressure sensors simultaneously or by combining sensors of various physiological types.

  4. Dimensionless Numbers Expressed in Terms of Common CVD Process Parameters

    NASA Technical Reports Server (NTRS)

    Kuczmarski, Maria A.

    1999-01-01

    A variety of dimensionless numbers related to momentum and heat transfer are useful in Chemical Vapor Deposition (CVD) analysis. These numbers are not traditionally calculated by directly using reactor operating parameters, such as temperature and pressure. In this paper, these numbers have been expressed in a form that explicitly shows their dependence upon the carrier gas, reactor geometry, and reactor operation conditions. These expressions were derived for both monatomic and diatomic gases using estimation techniques for viscosity, thermal conductivity, and heat capacity. Values calculated from these expressions compared well to previously published values. These expressions provide a relatively quick method for predicting changes in the flow patterns resulting from changes in the reactor operating conditions.

  5. Prospects of the complex development of highly parameter geothermal brines

    NASA Astrophysics Data System (ADS)

    Alkhasov, A. B.; Alkhasova, D. A.; Ramazanov, A. Sh.; Kasparova, M. A.

    2015-06-01

    The high efficiency of complex processing of high-temperature hydrothermal brines with utilization of heat energy in a binary geothermal power plant and subsequent extraction of solved chemical compounds is shown. Promising technological schemes are given, where electric power, which is generated in the binary geothermal power plant, is used in a block to recover chemistry components. The technology for integrated processing of geothermal brines of the chloride-sodium-calcium type is developed, which provides the manufacture not only of marketable products but also of practically overall reagents of processed water that are necessary to realize the technology. Priority areas for development are indicated, and the preliminary estimates for a Berikey geothermal deposit are given. It is shown that only established resources of thermal brines of the Berikey deposit make it possible to produce more than 2000 t of lithium carbonate and, thereby, to completely provide Russian industry requirements for it.

  6. Development of a comprehensive weld process model

    SciTech Connect

    Radhakrishnan, B.; Zacharia, T.; Paul, A.

    1997-05-01

    This cooperative research and development agreement (CRADA) between Concurrent Technologies Corporation (CTC) and Lockheed Martin Energy Systems (LMES) combines CTC`s expertise in the welding area and that of LMES to develop computer models and simulation software for welding processes. This development is of significant impact to the industry, including materials producers and fabricators. The main thrust of the research effort was to develop a comprehensive welding simulation methodology. A substantial amount of work has been done by several researchers to numerically model several welding processes. The primary drawback of most of the existing models is the lack of sound linkages between the mechanistic aspects (e.g., heat transfer, fluid flow, and residual stress) and the metallurgical aspects (e.g., microstructure development and control). A comprehensive numerical model which can be used to elucidate the effect of welding parameters/conditions on the temperature distribution, weld pool shape and size, solidification behavior, and microstructure development, as well as stresses and distortion, does not exist. It was therefore imperative to develop a comprehensive model which would predict all of the above phenomena during welding. The CRADA built upon an already existing three-dimensional (3-D) welding simulation model which was developed by LMES which is capable of predicting weld pool shape and the temperature history in 3-d single-pass welds. However, the model does not account for multipass welds, microstructural evolution, distortion and residual stresses. Additionally, the model requires large resources of computing time, which limits its use for practical applications. To overcome this, CTC and LMES have developed through this CRADA the comprehensive welding simulation model described above.

  7. Multiconductor Transmission-Line Theory That Includes an Antenna Process with a Lumped-Parameter Circuit

    NASA Astrophysics Data System (ADS)

    Toki, Hiroshi; Abe, Masayuki

    2016-03-01

    Electromagnetic noise was studied theoretically by developing a multiconductor transmission-line (MTL) theory derived from Maxwell’s equations without any approximations. The MTL theory naturally contains the antenna process, and for the case of three lines it is written in terms of normal, common, and antenna modes. Here we develop a theoretical method to solve the MTL equations by introducing boundary conditions consisting of a lumped-parameter circuit in order to describe the performance of any electric circuit for good performance without noise. The finite-difference time-domain (FDTD) method is a powerful algorithm to solve time-dependent coupled differential equations for a combined distributed- and lumped-parameter circuit.

  8. A Multiresolution Method for Parameter Estimation of Diffusion Processes

    PubMed Central

    Kou, S. C.; Olding, Benjamin P.; Lysy, Martin; Liu, Jun S.

    2014-01-01

    Diffusion process models are widely used in science, engineering and finance. Most diffusion processes are described by stochastic differential equations in continuous time. In practice, however, data is typically only observed at discrete time points. Except for a few very special cases, no analytic form exists for the likelihood of such discretely observed data. For this reason, parametric inference is often achieved by using discrete-time approximations, with accuracy controlled through the introduction of missing data. We present a new multiresolution Bayesian framework to address the inference difficulty. The methodology relies on the use of multiple approximations and extrapolation, and is significantly faster and more accurate than known strategies based on Gibbs sampling. We apply the multiresolution approach to three data-driven inference problems – one in biophysics and two in finance – one of which features a multivariate diffusion model with an entirely unobserved component. PMID:25328259

  9. Model development for naphthenic acids ozonation process.

    PubMed

    Al Jibouri, Ali Kamel H; Wu, Jiangning

    2015-02-01

    Naphthenic acids (NAs) are toxic constituents of oil sands process-affected water (OSPW) which is generated during the extraction of bitumen from oil sands. NAs consist mainly of carboxylic acids which are generally biorefractory. For the treatment of OSPW, ozonation is a very beneficial method. It can significantly reduce the concentration of NAs and it can also convert NAs from biorefractory to biodegradable. In this study, a factorial design (2(4)) was used for the ozonation of OSPW to study the influences of the operating parameters (ozone concentration, oxygen/ozone flow rate, pH, and mixing) on the removal of a model NAs in a semi-batch reactor. It was found that ozone concentration had the most significant effect on the NAs concentration compared to other parameters. An empirical model was developed to correlate the concentration of NAs with ozone concentration, oxygen/ozone flow rate, and pH. In addition, a theoretical analysis was conducted to gain the insight into the relationship between the removal of NAs and the operating parameters. PMID:25189805

  10. The Effects of Forming Parameters on Conical Ring Rolling Process

    PubMed Central

    Meng, Wen; Zhao, Guoqun; Guan, Yanjin

    2014-01-01

    The plastic penetration condition and biting-in condition of a radial conical ring rolling process with a closed die structure on the top and bottom of driven roll, simplified as RCRRCDS, were established. The reasonable value range of mandrel feed rate in rolling process was deduced. A coupled thermomechanical 3D FE model of RCRRCDS process was established. The changing laws of equivalent plastic strain (PEEQ) and temperature distributions with rolling time were investigated. The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied. The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the “obtuse angle zone” of ring's cross-section are higher than those at “acute angle zone”; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces. As the ring's outer radius growth rate increases at its reasonable value ranges, the uniformities of PEEQ and temperature distributions increase. Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained. PMID:25202716

  11. Development of a multi-parameter system for Antarctic researching

    NASA Astrophysics Data System (ADS)

    Garcia, Alicia; Peci, Luis Miguel; Berrocoso, Manuel; Fernandez-Ros, Alberto; Marrero, Jose Manuel; Ortiz, Ramon

    2014-05-01

    This work describes the development of a multi-parameter system for antarctic researching. The system permits the remote access and the connection of several modules in a network. An embedded ARM processor has been used, allowing a great flexibility in hardware configuration.The advantage of the system presented in this work is that it allows the rapid development of a monitoring network that uses the latest technologies of embedded systems. These embedded systems offer the possibility of developing the software necessary for managing the sensors and instruments available. Data can be transmitted in near real time or on demand to a Data Reception Center (DRC). The local storage allows retrieving data when the transmission fails and uses only short transmission periods rather than continuous transmission. The price of both hardware and software is very low. The use of a complete Linux solution (Debian) as Operating System permits a quick, easy application development to control sensors and communications. This provides all the capabilities required and great stability with relatively low energy consumption. The cost of the components and applications development is low since they are widely used in different fields. Sensors and commercial modules have been combined with other self-developed modules. The Modular System described has been deployed at Deception Island (Antarctica), within the Spanish Antarctic Program, and has proved successful for monitoring and researching the geodinamical activity, with proven reliability and efficient operation under extreme conditions. Deception Islan is an active volcano with some geothermal areas, this fact has allowed to develop a power system using Peltier cells. In another context, i.e., the recent volcanic activity on El Hierro Island (Canary Islands) in 2011, this technology has been used for the seismic equipment and GPS systems deployed, thus showing its efficiency in the monitoring of a volcanic crisis.

  12. A stochastic process approach of the drake equation parameters

    NASA Astrophysics Data System (ADS)

    Glade, Nicolas; Ballet, Pascal; Bastien, Olivier

    2012-04-01

    The number N of detectable (i.e. communicating) extraterrestrial civilizations in the Milky Way galaxy is usually calculated by using the Drake equation. This equation was established in 1961 by Frank Drake and was the first step to quantifying the Search for ExtraTerrestrial Intelligence (SETI) field. Practically, this equation is rather a simple algebraic expression and its simplistic nature leaves it open to frequent re-expression. An additional problem of the Drake equation is the time-independence of its terms, which for example excludes the effects of the physico-chemical history of the galaxy. Recently, it has been demonstrated that the main shortcoming of the Drake equation is its lack of temporal structure, i.e., it fails to take into account various evolutionary processes. In particular, the Drake equation does not provides any error estimation about the measured quantity. Here, we propose a first treatment of these evolutionary aspects by constructing a simple stochastic process that will be able to provide both a temporal structure to the Drake equation (i.e. introduce time in the Drake formula in order to obtain something like N(t)) and a first standard error measure.

  13. Geomechanical Parameters in Fracturing Process of Layered Rocks

    NASA Astrophysics Data System (ADS)

    Mighani, S.; Sondergeld, C. H.; Rai, C. S.

    2013-12-01

    Hydraulic fracturing is crucial to geothermal and hydrocarbon recovery. Predicting performance based on rock characteristics (micro and macro) is essential to effective stimulation. We studied two extreme rock types: 1) Lyons sandstone, a brittle, low porosity, low permeability, weakly anisotropic material and 2) pyrophyllite, a strongly anisotropic metamorphic rock similar chemically and mechanically to shale, having extremely low porosity and permeability. Mineralogy, porosity, permeability, mercury capillary pressure, grain size, μ-CT imaging and elastic anisotropy analysis describe these rocks. Brazilian disk tests were carried to observe the fracture initiation and propagation under tension. Fracture propagation velocity is measured using a high speed digital camera. Strain gauges and acoustic emission (AE) sensors recorded deformation leading to and during failure. SEM imaging and surface profilometry were used to study the post-failure fracture systems and failed surface topology. The fracture process zone (FPZ) is mapped and evaluated using a mosaic of stitched SEM images. The fracture permeability was measured as a function of effective stress and compared to fracture permeability models. The effect of anisotropy on fracturing (Mode I and Mode II fractures) was also investigated rotating the fabric direction of the tested disks relative to the loading axis through increments of 15 degrees. Results indicate differences in fracturing process of these two rock types. Pyrophyllite displays a localized ductile behavior in the process zone resulting in a narrower fracture with a higher propagation velocity and far less AE activity. Pyrophyllite shows 70 % higher tensile strength compared to Lyons sandstone even though it becomes ductile at much lower pressures. The sandstone shows a wide brittle fracture with larger FPZ and better permeability at elevated effective pressures. The greater number of AE activity associated with higher energy events confirms the

  14. Development of an AQUA Based Near-Surface Parameter Retrieval

    NASA Technical Reports Server (NTRS)

    Roberts, Brent; Clayson, Carol Anne

    2010-01-01

    The production of a satellite based turbulent surface flux product relies critically upon the near-surface input parameters. Development of retrieval algorithms for the necessary near-surface variables of wind speed, specific humidity, air temperature, and sea surface temperature has proceeded relatively independent of each another until recently. The use of a neural network approach using Special Sensor Microwave/Imager (SSM/I) data in conjunction with a first guess sea surface temperature has led to successful retrieval of all parameters simultaneously. However, SSM/I frequencies lack inherent sensitivity to the sea surface temperature (SST). Recent studies have found improved air temperature and humidity retrievals can be obtained via inclusion of microwave sounding channels weighted in the lower troposphere. The inclusion of SSM/I-like frequencies as well as SST-sensitive microwave channels on AMSR-E along with AMSU-A sounding data onboard the AQUA platform provides an unique opportunity. That is the ability to provide near-simultaneous (in space and time) measurements allowing the retrieval of all the near-surface variables, including SST. This study shows results of a new algorithm designed to take advantage of the unique sampling ability of AQUA based sensors. Results from a neural network based methodology will be shown as compared to in-situ based observations of near-surface variables. Implications for creation of an AQUA based turbulent surface product are also discussed.

  15. Effect of Electron Beam Freeform Fabrication (EBF3) Processing Parameters on Composition of Ti-6-4

    NASA Technical Reports Server (NTRS)

    Lach, Cynthia L.; Taminger, Karen; Schuszler, A. Bud, II; Sankaran, Sankara; Ehlers, Helen; Nasserrafi, Rahbar; Woods, Bryan

    2007-01-01

    The Electron Beam Freeform Fabrication (EBF3) process developed at NASA Langley Research Center was evaluated using a design of experiments approach to determine the effect of processing parameters on the composition and geometry of Ti-6-4 deposits. The effects of three processing parameters: beam power, translation speed, and wire feed rate, were investigated by varying one while keeping the remaining parameters constant. A three-factorial, three-level, fully balanced mutually orthogonal array (L27) design of experiments approach was used to examine the effects of low, medium, and high settings for the processing parameters on the chemistry, geometry, and quality of the resulting deposits. Single bead high deposits were fabricated and evaluated for 27 experimental conditions. Loss of aluminum in Ti-6-4 was observed in EBF3 processing due to selective vaporization of the aluminum from the sustained molten pool in the vacuum environment; therefore, the chemistries of the deposits were measured and compared with the composition of the initial wire and base plate to determine if the loss of aluminum could be minimized through careful selection of processing parameters. The influence of processing parameters and coupling between these parameters on bulk composition, measured by Direct Current Plasma (DCP), local microchemistries determined by Wavelength Dispersive Spectrometry (WDS), and deposit geometry will also be discussed.

  16. Developing an Interpretation of Item Parameters for Personality Items: Content Correlates of Parameter Estimates.

    ERIC Educational Resources Information Center

    Zickar, Michael J.; Ury, Karen L.

    2002-01-01

    Attempted to relate content features of personality items to item parameter estimates from the partial credit model of E. Muraki (1990) by administering the Adjective Checklist (L. Goldberg, 1992) to 329 undergraduates. As predicted, the discrimination parameter was related to the item subtlety ratings of personality items but the level of word…

  17. Development of a Comprehensive Weld Process Model

    SciTech Connect

    Radhakrishnan, B.; Zacharia, T.

    1997-05-01

    This cooperative research and development agreement (CRADA) between Concurrent Technologies Corporation (CTC) and Lockheed Martin Energy Systems (LMES) combines CTC's expertise in the welding area and that of LMES to develop computer models and simulation software for welding processes. This development is of significant impact to the industry, including materials producers and fabricators. The main thrust of the research effort was to develop a comprehensive welding simulation methodology. A substantial amount of work has been done by several researchers to numerically model several welding processes. The primary drawback of most of the existing models is the lack of sound linkages between the mechanistic aspects (e.g., heat transfer, fluid flow, and residual stress) and the metallurgical aspects (e.g., microstructure development and control). A comprehensive numerical model which can be used to elucidate the effect of welding parameters/conditions on the temperature distribution, weld pool shape and size, solidification behavior, and microstructure development, as well as stresses and distortion, does not exist. It was therefore imperative to develop a comprehensive model which would predict all of the above phenomena during welding. The CRADA built upon an already existing three- dimensional (3-D) welding simulation model which was developed by LMES which is capable of predicting weld pool shape and the temperature history in 3-d single-pass welds. However, the model does not account for multipass welds, microstructural evolution, distortion and residual stresses. Additionally, the model requires large resources of computing time, which limits its use for practical applications. To overcome this, CTC and LMES have developed through this CRADA the comprehensive welding simulation model described above. The following technical tasks have been accomplished as part of the CRADA. 1. The LMES welding code has been ported to the Intel Paragon parallel computer at ORNL

  18. Data Mining and Optimization Tools for Developing Engine Parameters Tools

    NASA Technical Reports Server (NTRS)

    Dhawan, Atam P.

    1998-01-01

    This project was awarded for understanding the problem and developing a plan for Data Mining tools for use in designing and implementing an Engine Condition Monitoring System. From the total budget of $5,000, Tricia and I studied the problem domain for developing ail Engine Condition Monitoring system using the sparse and non-standardized datasets to be available through a consortium at NASA Lewis Research Center. We visited NASA three times to discuss additional issues related to dataset which was not made available to us. We discussed and developed a general framework of data mining and optimization tools to extract useful information from sparse and non-standard datasets. These discussions lead to the training of Tricia Erhardt to develop Genetic Algorithm based search programs which were written in C++ and used to demonstrate the capability of GA algorithm in searching an optimal solution in noisy datasets. From the study and discussion with NASA LERC personnel, we then prepared a proposal, which is being submitted to NASA for future work for the development of data mining algorithms for engine conditional monitoring. The proposed set of algorithm uses wavelet processing for creating multi-resolution pyramid of the data for GA based multi-resolution optimal search. Wavelet processing is proposed to create a coarse resolution representation of data providing two advantages in GA based search: 1. We will have less data to begin with to make search sub-spaces. 2. It will have robustness against the noise because at every level of wavelet based decomposition, we will be decomposing the signal into low pass and high pass filters.

  19. Evaluating Processes, Parameters and Observations Using Cross Validation and Computationally Frugal Sensitivity Analysis Methods

    NASA Astrophysics Data System (ADS)

    Foglia, L.; Mehl, S.; Hill, M. C.

    2013-12-01

    Sensitivity analysis methods are used to identify measurements most likely to provide important information for model development and predictions and therefore identify critical processes. Methods range from computationally demanding Monte Carlo and cross-validation methods, to very computationally efficient linear methods. The methods are able to account for interrelations between parameters, but some argue that because linear methods neglect the effects of model nonlinearity, they are not worth considering when examining complex, nonlinear models of environmental systems. However, when faced with computationally demanding models needed to simulate, for example, climate change, the chance of obtaining fundamental insights (such as important and relationships between predictions and parameters) with few model runs is tempting. In the first part of this work, comparisons of local sensitivity analysis and cross-validation are conducted using a nonlinear groundwater model of the Maggia Valley, Southern Switzerland; sensitivity analysis are then applied to an integrated hydrological model of the same system where the impact of more processes and of using different sets of observations on the model results are considered; applicability to models of a variety of situations (climate, water quality, water management) is inferred. Results show that the frugal linear methods produced about 70% of the insight from about 2% of the model runs required by the computationally demanding methods. Regarding important observations, linear methods were not always able to distinguish between moderately and unimportant observations. However, they consistently identified the most important observations which are critical to characterize relationships between parameters and to assess the worth of potential new data collection efforts. Importance both to estimate parameters and predictions of interest was readily identified. The results suggest that it can be advantageous to consider local

  20. Parameter Sensitivity and Laboratory Benchmarking of a Biogeochemical Process Model for Enhanced Anaerobic Dechlorination

    NASA Astrophysics Data System (ADS)

    Kouznetsova, I.; Gerhard, J. I.; Mao, X.; Barry, D. A.; Robinson, C.; Brovelli, A.; Harkness, M.; Fisher, A.; Mack, E. E.; Payne, J. A.; Dworatzek, S.; Roberts, J.

    2008-12-01

    A detailed model to simulate trichloroethene (TCE) dechlorination in anaerobic groundwater systems has been developed and implemented through PHAST, a robust and flexible geochemical modeling platform. The approach is comprehensive but retains flexibility such that models of varying complexity can be used to simulate TCE biodegradation in the vicinity of nonaqueous phase liquid (NAPL) source zones. The complete model considers a full suite of biological (e.g., dechlorination, fermentation, sulfate and iron reduction, electron donor competition, toxic inhibition, pH inhibition), physical (e.g., flow and mass transfer) and geochemical processes (e.g., pH modulation, gas formation, mineral interactions). Example simulations with the model demonstrated that the feedback between biological, physical, and geochemical processes is critical. Successful simulation of a thirty-two-month column experiment with site soil, complex groundwater chemistry, and exhibiting both anaerobic dechlorination and endogenous respiration, provided confidence in the modeling approach. A comprehensive suite of batch simulations was then conducted to estimate the sensitivity of predicted TCE degradation to the 36 model input parameters. A local sensitivity analysis was first employed to rank the importance of parameters, revealing that 5 parameters consistently dominated model predictions across a range of performance metrics. A global sensitivity analysis was then performed to evaluate the influence of a variety of full parameter data sets available in the literature. The modeling study was performed as part of the SABRE (Source Area BioREmediation) project, a public/private consortium whose charter is to determine if enhanced anaerobic bioremediation can result in effective and quantifiable treatment of chlorinated solvent DNAPL source areas. The modelling conducted has provided valuable insight into the complex interactions between processes in the evolving biogeochemical systems

  1. Data Mining and Optimization Tools for Developing Engine Parameters Tools

    NASA Technical Reports Server (NTRS)

    Dhawan, Atam P.

    1998-01-01

    This project was awarded for understanding the problem and developing a plan for Data Mining tools for use in designing and implementing an Engine Condition Monitoring System. Tricia Erhardt and I studied the problem domain for developing an Engine Condition Monitoring system using the sparse and non-standardized datasets to be available through a consortium at NASA Lewis Research Center. We visited NASA three times to discuss additional issues related to dataset which was not made available to us. We discussed and developed a general framework of data mining and optimization tools to extract useful information from sparse and non-standard datasets. These discussions lead to the training of Tricia Erhardt to develop Genetic Algorithm based search programs which were written in C++ and used to demonstrate the capability of GA algorithm in searching an optimal solution in noisy, datasets. From the study and discussion with NASA LeRC personnel, we then prepared a proposal, which is being submitted to NASA for future work for the development of data mining algorithms for engine conditional monitoring. The proposed set of algorithm uses wavelet processing for creating multi-resolution pyramid of tile data for GA based multi-resolution optimal search.

  2. Development of high resolution land surface parameters for the Community Land Model

    NASA Astrophysics Data System (ADS)

    Ke, Y.; Leung, L. R.; Huang, M.; Coleman, A. M.; Li, H.; Wigmosta, M. S.

    2012-06-01

    There is a growing need for high-resolution land surface parameters as land surface models are being applied at increasingly higher spatial resolution offline as well as in regional and global models. The default land surface parameters for the most recent version of the Community Land Model (i.e. CLM 4.0) are at 0.5° or coarser resolutions, released with the model from the National Center for Atmospheric Research (NCAR). Plant Functional Types (PFTs), vegetation properties such as Leaf Area Index (LAI), Stem Area Index (SAI), and non-vegetated land covers were developed using remotely-sensed datasets retrieved in late 1990's and the beginning of this century. In this study, we developed new land surface parameters for CLM 4.0, specifically PFTs, LAI, SAI and non-vegetated land cover composition, at 0.05° resolution globally based on the most recent MODIS land cover and improved MODIS LAI products. Compared to the current CLM 4.0 parameters, the new parameters produced a decreased coverage by bare soil and trees, but an increased coverage by shrub, grass, and cropland. The new parameters result in a decrease in global seasonal LAI, with the biggest decrease in boreal forests; however, the new parameters also show a large increase in LAI in tropical forest. Differences between the new and the current parameters are mainly caused by changes in the sources of remotely sensed data and the representation of land cover in the source data. The new high-resolution land surface parameters have been used in a coupled land-atmosphere model (WRF-CLM) applied to the western US to demonstrate their use in high-resolution modeling. Future work will include global offline CLMsimulations to examine the impacts of source data resolution and subsequent land parameter changes on simulated land surface processes.

  3. Process Accountability in Curriculum Development.

    ERIC Educational Resources Information Center

    Gooler, Dennis D.; Grotelueschen, Arden

    This paper urges the curriculum developer to assume the accountability for his decisions necessitated by the actual ways our society functions. The curriculum developer is encouraged to recognize that he is a salesman with a commodity (the curriculum). He is urged to realize that if he cannot market the package to the customers (the various…

  4. Developing an Internal Processing System.

    ERIC Educational Resources Information Center

    DeFord, Diane

    1997-01-01

    The goal in Reading Recovery is to support children to develop "in the head" operations or strategies that aid them to solve problems as they read and write continuous text. To help children in organizing experience and correct any idiosyncratic or unreliable relationships, teachers must understand how children develop their internal processing…

  5. An Instructional Systems Development Process.

    ERIC Educational Resources Information Center

    Campbell, Clifton P.

    Instructional systems development (ISD) is a systems approach to curriculum development and instructional delivery. It is oriented toward occupational needs with an emphasis on what it is that students must learn to perform specific tasks, what facilities best provide a setting for the neccessary learning, and what instructional methods and media…

  6. Molecular dynamics simulations: Parameter evaluation, application and development

    NASA Astrophysics Data System (ADS)

    Zhou, Jin

    Molecular dynamics (MD) simulation is a theoretical technique for investigating the physical properties of a wide variety of molecules. This dissertation contains my studies on three important parts of the MD simulation: evaluation of parameters in empirical energy functions widely used in MD simulations, application of MD simulation on experimentally interested biological molecules and development of new methods for constraint dynamics simulations. All the work in this thesis made use of CHARMM as an MD simulation tool. The MD simulation uses empirical energy functions parameterized by a set of parameters. These parameters play an important role in the quality of the simulations. I evaluated nine parameter sets from Harvard University and Molecular Simulations, Inc. for protein simulations by the MD simulations of hydrated form of carboxy- myoglobin and interleukin-1/beta, which are rich in two typical protein structure motifs, helix and β sheet structures respectively. It is found that some sets are good at representing helical structure proteins while others are good at β sheet proteins. But all of them need improvement on representing motions at low temperature. Experimental evidence indicates that the 1A coiled-coil domains of the Intermediate Filament (IF) proteins consisting of coiled human keratins 1 and 10 (K1 and K10) are 'hot spots' for substitutional mutations. Some of these mutations are correlated to the human skin diseases-epidermolytic hyperkeratiosis (EH) and epidermolysis bullosa simplex (EBS). The MD simulation technique is used here for the first time to model and simulate these proteins to elucidate the molecular-level effects of these mutations. Lacking the experimental crystal structures, the initial structure of 1A domain of the wild type Intermediate Filament protein and its mutants were modeled from scratch to reproduce the well- known properties of the proteins of this kind followed by identical MD simulations. The important result is

  7. Process optimization in high-average-power ultrashort pulse laser microfabrication: how laser process parameters influence efficiency, throughput and quality

    NASA Astrophysics Data System (ADS)

    Schille, Joerg; Schneider, Lutz; Loeschner, Udo

    2015-09-01

    In this paper, laser processing of technical grade stainless steel and copper using high-average-power ultrashort pulse lasers is studied in order to gain deeper insight into material removal for microfabrication. A high-pulse repetition frequency picosecond and femtosecond laser is used in conjunction with high-performance galvanometer scanners and an in-house developed two-axis polygon scanner system. By varying the processing parameters such as wavelength, pulse length, fluence and repetition rate, cavities of standardized geometry are fabricated and analyzed. From the depths of the cavities produced, the ablation rate and removal efficiency are estimated. In addition, the quality of the cavities is evaluated by means of scanning electron microscope micrographs or rather surface roughness measurements. From the results obtained, the influence of the machining parameters on material removal and machining quality is discussed. In addition, it is shown that both material removal rate and quality increase by using femtosecond compared to picosecond laser pulses. On stainless steel, a maximum throughput of 6.81 mm3/min is achieved with 32 W femtosecond laser powers; if using 187 W picosecond laser powers, the maximum is 15.04 mm3/min, respectively. On copper, the maximum throughputs are 6.1 mm3/min and 21.4 mm3/min, obtained with 32 W femtosecond and 187 W picosecond laser powers. The findings indicate that ultrashort pulses in the mid-fluence regime yield most efficient material removal. In conclusion, from the results of this analysis, a range of optimum processing parameters are derived feasible to enhance machining efficiency, throughput and quality in high-rate micromachining. The work carried out here clearly opens the way to significant industrial applications.

  8. [Correlation of dry granulation process parameters and granule quality based on multiple regression analysis].

    PubMed

    Cao, Han-Han; Du, Ruo-Fei; Yang, Jia-Ning; Feng, Yi

    2014-03-01

    In this paper, microcrystalline cellulose WJ101 was used as a model material to investigate the effect of various process parameters on granule yield and friability after dry granulation with a single factor and the effect of comprehensive inspection process parameters on the effect of granule yield and friability, then the correlation between process parameters and granule quality was established. The regress equation was established between process parameters and granule yield and friability by multiple regression analysis, the affecting the order of the size of the order of the process parameters on granule yield and friability was: rollers speed > rollers pressure > speed of horizontal feed. Granule yield was positively correlated with pressure and speed of horizontal feed and negatively correlated rollers speed, while friability was on the contrary. By comparison, fitted value and real value, fitted and real value are basically the same of no significant differences (P > 0.05) and with high precision and reliability. PMID:24961115

  9. A study on the performance of synthetic type charts when process parameters are estimated

    NASA Astrophysics Data System (ADS)

    You, Huay Woon; Khoo, Michael Boon Chong; Teh, Sin Yin

    2015-10-01

    There are two types of synthetic charts for monitoring the process mean, i.e. synthetic X ¯ chart and synthetic double sampling X ¯ chart (SDS X ¯ chart). In most applications, the process parameters, such as the in-control mean and the in-control standard deviation are usually unknown. Under such circumstances, both these process parameters need to be estimated from an in-control Phase I dataset. Thus, it is vital to study the performance of these charts when the process parameters are unknown. In this paper, the performance of two synthetic type charts with estimated process parameters will be studied. The average number of observations to signal (ANOS) criterion will be used to evaluate the performances of these charts. This study shows that the performances of synthetic type charts are significantly affected by the estimation of process parameters. Furthermore, a large number of Phase I samples is required so that the synthetic type charts with estimated process parameters will have reasonable performances as their corresponding known process parameters counterparts, especially when the sample size and size of process mean shift is small.

  10. Development of a distributed-parameter mathematical model for simulation of cryogenic wind tunnels

    NASA Technical Reports Server (NTRS)

    Tripp, J. S.

    1983-01-01

    A one-dimensional distributed-parameter dynamic model of a cryogenic wind tunnel was developed which accounts for internal and external heat transfer, viscous momentum losses, and slotted-test-section dynamics. Boundary conditions imposed by liquid-nitrogen injection, gas venting, and the tunnel fan were included. A time-dependent numerical solution to the resultant set of partial differential equations was obtained on a CDC CYBER 203 vector-processing digital computer at a usable computational rate. Preliminary computational studies were performed by using parameters of the Langley 0.3-Meter Transonic Cryogenic Tunnel. Studies were performed by using parameters from the National Transonic Facility (NTF). The NTF wind-tunnel model was used in the design of control loops for Mach number, total temperature, and total pressure and for determining interactions between the control loops. It was employed in the application of optimal linear-regulator theory and eigenvalue-placement techniques to develop Mach number control laws.

  11. Numerical study of the process parameters in spark plasma sintering (sps)

    NASA Astrophysics Data System (ADS)

    Chowdhury, Redwan Jahid

    Spark plasma sintering (SPS) is one of the most widely used sintering techniques that utilizes pulsed direct current together with uniaxial pressure to consolidate a wide variety of materials. The unique mechanisms of SPS enable it to sinter powder compacts at a lower temperature and in a shorter time than the conventional hot pressing, hot isostatic pressing and vacuum sintering process. One of the limitations of SPS is the presence of temperature gradients inside the sample, which could result in non-uniform physical and microstructural properties. Detailed study of the temperature and current distributions inside the sintered sample is necessary to minimize the temperature gradients and achieve desired properties. In the present study, a coupled thermal-electric model was developed using finite element codes in ABAQUS software to investigate the temperature and current distributions inside the conductive and non-conductive samples. An integrated experimental-numerical methodology was implemented to determine the system contact resistances accurately. The developed sintering model was validated by a series of experiments, which showed good agreements with simulation results. The temperature distribution inside the sample depends on some process parameters such as sample and tool geometry, punch and die position, applied current and thermal insulation around the die. The role of these parameters on sample temperature distribution was systematically analyzed. The findings of this research could prove very useful for the reliable production of large size sintered samples with controlled and tailored properties.

  12. Mathematical modeling and analysis of EDM process parameters based on Taguchi design of experiments

    NASA Astrophysics Data System (ADS)

    Laxman, J.; Raj, K. Guru

    2015-12-01

    Electro Discharge Machining is a process used for machining very hard metals, deep and complex shapes by metal erosion in all types of electro conductive materials. The metal is removed through the action of an electric discharge of short duration and high current density between the tool and the work piece. The eroded metal on the surface of both work piece and the tool is flushed away by the dielectric fluid. The objective of this work is to develop a mathematical model for an Electro Discharge Machining process which provides the necessary equations to predict the metal removal rate, electrode wear rate and surface roughness. Regression analysis is used to investigate the relationship between various process parameters. The input parameters are taken as peak current, pulse on time, pulse off time, tool lift time. and the Metal removal rate, electrode wear rate and surface roughness are as responses. Experiments are conducted on Titanium super alloy based on the Taguchi design of experiments i.e. L27 orthogonal experiments.

  13. Simulation Modeling of Software Development Processes

    NASA Technical Reports Server (NTRS)

    Calavaro, G. F.; Basili, V. R.; Iazeolla, G.

    1996-01-01

    A simulation modeling approach is proposed for the prediction of software process productivity indices, such as cost and time-to-market, and the sensitivity analysis of such indices to changes in the organization parameters and user requirements. The approach uses a timed Petri Net and Object Oriented top-down model specification. Results demonstrate the model representativeness, and its usefulness in verifying process conformance to expectations, and in performing continuous process improvement and optimization.

  14. Development of methodology for controlling the parameters of TP

    NASA Astrophysics Data System (ADS)

    Klochkova, K. V.; Petrovich, S. V.; Simonova, L. A.; Yusupov, L. R.

    2015-06-01

    This article describes TP control step of the intelligent system for predicting the properties of CGI, which includes three parts: the selection of parameters for comparison, the comparison with the simulation results, the change of the current TP. The list of parameters under which control in the production is carried out has been determined, the adjustment algorithm of TP is designed.

  15. Processing parameters associated with scale-up of balloon film production

    NASA Technical Reports Server (NTRS)

    Simpson, D. M.; Harrison, I. R.

    1993-01-01

    A method is set forth for assessing strain-rate profiles that can be used to develop a scale-up theory for blown-film extrusion. Strain rates are evaluated by placing four ink dots on the stalk of an extruded bubble to follow the displacements of the dots as a function of time. The instantaneous Hencky strain is obtained with the displacement data and plotted for analysis. Specific attention is given to potential sources of error in the distance measurements and corrections for these complex bubble geometries. The method is shown to be effective for deriving strain-rate data related to different processing parameters for the production of balloon film. The strain rates can be compared to frostline height, blow-up ratio, and take-up ratio to optimize these processing variables.

  16. Development of the Production Process Model Based on the Controllable Input Factors

    NASA Astrophysics Data System (ADS)

    Plotnikova, I.; Redko, L.; Titova, O.; Chaykovskaya, O.

    2016-06-01

    The research aims to study noncompliances in the production process, defects in chipboard manufacturing and the related costs. The influence of production process parameters on the parameters of finished products and correlation dependence of considered parameters have been shown. The mathematical model of the multiple-factor production process has been developed.

  17. Process Development of Porcelain Ceramic Material with Binder Jetting Process for Dental Applications

    NASA Astrophysics Data System (ADS)

    Miyanaji, Hadi; Zhang, Shanshan; Lassell, Austin; Zandinejad, Amirali; Yang, Li

    2016-03-01

    Custom ceramic structures possess significant potentials in many applications such as dentistry and aerospace where extreme environments are present. Specifically, highly customized geometries with adequate performance are needed for various dental prostheses applications. This paper demonstrates the development of process and post-process parameters for a dental porcelain ceramic material using binder jetting additive manufacturing (AM). Various process parameters such as binder amount, drying power level, drying time and powder spread speed were studied experimentally for their effect on geometrical and mechanical characteristics of green parts. In addition, the effects of sintering and printing parameters on the qualities of the densified ceramic structures were also investigated experimentally. The results provide insights into the process-property relationships for the binder jetting AM process, and some of the challenges of the process that need to be further characterized for the successful adoption of the binder jetting technology in high quality ceramic fabrications are discussed.

  18. An Advanced User Interface Approach for Complex Parameter Study Process Specification in the Information Power Grid

    NASA Technical Reports Server (NTRS)

    Yarrow, Maurice; McCann, Karen M.; Biswas, Rupak; VanderWijngaart, Rob; Yan, Jerry C. (Technical Monitor)

    2000-01-01

    The creation of parameter study suites has recently become a more challenging problem as the parameter studies have now become multi-tiered and the computational environment has become a supercomputer grid. The parameter spaces are vast, the individual problem sizes are getting larger, and researchers are now seeking to combine several successive stages of parameterization and computation. Simultaneously, grid-based computing offers great resource opportunity but at the expense of great difficulty of use. We present an approach to this problem which stresses intuitive visual design tools for parameter study creation and complex process specification, and also offers programming-free access to grid-based supercomputer resources and process automation.

  19. T3PS v1.0: Tool for Parallel Processing in Parameter Scans

    NASA Astrophysics Data System (ADS)

    Maurer, Vinzenz

    2016-01-01

    T3PS is a program that can be used to quickly design and perform parameter scans while easily taking advantage of the multi-core architecture of current processors. It takes an easy to read and write parameter scan definition file format as input. Based on the parameter ranges and other options contained therein, it distributes the calculation of the parameter space over multiple processes and possibly computers. The derived data is saved in a plain text file format readable by most plotting software. The supported scanning strategies include: grid scan, random scan, Markov Chain Monte Carlo, numerical optimization. Several example parameter scans are shown and compared with results in the literature.

  20. Optimization of Machining Process Parameters for Surface Roughness of Al-Composites

    NASA Astrophysics Data System (ADS)

    Sharma, S.

    2013-10-01

    Metal matrix composites (MMCs) have become a leading material among the various types of composite materials for different applications due to their excellent engineering properties. Among the various types of composites materials, aluminum MMCs have received considerable attention in automobile and aerospace applications. These materials are known as the difficult-to-machine materials because of the hardness and abrasive nature of reinforcement element-like silicon carbide particles. In the present investigation Al-SiC composite was produced by stir casting process. The Brinell hardness of the alloy after SiC addition had increased from 74 ± 2 to 95 ± 5 respectively. The composite was machined using CNC turning center under different machining parameters such as cutting speed (S), feed rate (F), depth of cut (D) and nose radius (R). The effect of machining parameters on surface roughness (Ra) was studied using response surface methodology. Face centered composite design with three levels of each factor was used for surface roughness study of the developed composite. A response surface model for surface roughness was developed in terms of main factors (S, F, D and R) and their significant interactions (SD, SR, FD and FR). The developed model was validated by conducting experiments under different conditions. Further the model was optimized for minimum surface roughness. An error of 3-7 % was observed in the modeled and experimental results. Further, it was fond that the surface roughness of Al-alloy at optimum conditions is lower than that of Al-SiC composite.

  1. Probabilistic parameter estimation of activated sludge processes using Markov Chain Monte Carlo.

    PubMed

    Sharifi, Soroosh; Murthy, Sudhir; Takács, Imre; Massoudieh, Arash

    2014-03-01

    One of the most important challenges in making activated sludge models (ASMs) applicable to design problems is identifying the values of its many stoichiometric and kinetic parameters. When wastewater characteristics data from full-scale biological treatment systems are used for parameter estimation, several sources of uncertainty, including uncertainty in measured data, external forcing (e.g. influent characteristics), and model structural errors influence the value of the estimated parameters. This paper presents a Bayesian hierarchical modeling framework for the probabilistic estimation of activated sludge process parameters. The method provides the joint probability density functions (JPDFs) of stoichiometric and kinetic parameters by updating prior information regarding the parameters obtained from expert knowledge and literature. The method also provides the posterior correlations between the parameters, as well as a measure of sensitivity of the different constituents with respect to the parameters. This information can be used to design experiments to provide higher information content regarding certain parameters. The method is illustrated using the ASM1 model to describe synthetically generated data from a hypothetical biological treatment system. The results indicate that data from full-scale systems can narrow down the ranges of some parameters substantially whereas the amount of information they provide regarding other parameters is small, due to either large correlations between some of the parameters or a lack of sensitivity with respect to the parameters. PMID:24384542

  2. Parameter-Level Data Flow Modeling Oriented to Product Design Process

    NASA Astrophysics Data System (ADS)

    Li, Shen; Shao, Xiao Dong; Zhang, Zhi Hua; Ge, Xiao Bo

    2015-12-01

    In this paper, a method of data flow modeling for a product design process oriented to data parameter is proposed. The data parameters are defined, which are classified as the basic data parameters and complex data parameters. The mechanism of the mapping relationship between different forms of documents and some basic data parameters, and a data transmission based on parameters, are constructed. Aiming at the characteristics of the iterative design process, the parameters version mechanism including node modification and iteration information is proposed. The data parameters transmission relationships are represented by a parameters network model (PNM) based on a directed graph. Finally, through the table of data parameters mapping onto the workflow node and PNM, the data ports and data links in the data flow model are generated automatically by the program. Validation in the 15-meter-diameter S/Ka frequency band antenna design process of the “Reflector, Back frame and Center part design” data flow model shows that the method can effectively shorten the time of data flow modeling and improve the data transmission efficiency.

  3. Managing the Software Development Process

    NASA Astrophysics Data System (ADS)

    Lubelczyk, J.; Parra, A.

    The goal of any software development project is to produce a product that is delivered on time, within the allocated budget, and with the capabilities expected by the customer and unfortunately, this goal is rarely achieved. However, a properly managed project in a mature software engineering environment can consistently achieve this goal. In this paper we provide an introduction to three project success factors, a properly managed project, a competent project manager, and a mature software engineering environment. We will also present an overview of the benefits of a mature software engineering environment based on 24 years of data from the Software Engineering Lab, and suggest some first steps that an organization can take to begin benefiting from this environment. The depth and breadth of software engineering exceeds this paper, various references are cited with a goal of raising awareness and encouraging further investigation into software engineering and project management practices.

  4. Managing the Software Development Process

    NASA Technical Reports Server (NTRS)

    Lubelczky, Jeffrey T.; Parra, Amy

    1999-01-01

    The goal of any software development project is to produce a product that is delivered on time, within the allocated budget, and with the capabilities expected by the customer and unfortunately, this goal is rarely achieved. However, a properly managed project in a mature software engineering environment can consistently achieve this goal. In this paper we provide an introduction to three project success factors, a properly managed project, a competent project manager, and a mature software engineering environment. We will also present an overview of the benefits of a mature software engineering environment based on 24 years of data from the Software Engineering Lab, and suggest some first steps that an organization can take to begin benefiting from this environment. The depth and breadth of software engineering exceeds this paper, various references are cited with a goal of raising awareness and encouraging further investigation into software engineering and project management practices.

  5. Processes, observations and parameters in a coupled surface water-groundwater model

    NASA Astrophysics Data System (ADS)

    Foglia, Laura; Hill, Mary; Mehl, Steffen; Burlando, Paolo

    2013-04-01

    Hydrological models of surface-water flow and infiltration allow for a process-based representation of recharge to ground water models. Recharge is a fundamental and often difficult to quantify component of a groundwater system, in part because recharge and hydraulic conductivity changes tend to similarly affect hydraulic heads, the most common kind of observations in groundwater systems. Here the goal is to analyze the importance of using recharge derived from hydrologic processes for groundwater model development and furthermore the importance of a spatially distributed value of recharge. To achieve the goal we followed this procedure: 1) independently calibrate and test the groundwater and hydrological models (accomplished as described in Foglia et al., 2007GW, 2009WRR, in press WRR); 2) for the hydrological model, we present a new sensitivity analysis and calibration obtained with a set of observations that provides more detail at low flows, which was identified as important by Foglia et al. (2009); 3) couple the two models (here, one-way coupling transfers infiltration from the surface-water model to the groundwater model after multiplying by an estimated factor); 4) identify important parameters and observations using a sensitivity analysis conducted with linear statistics for this computationally demanding model; 5) use regression in an hypothesis testing framework to explore parameter and observation importance further and also explore resulting estimates and model fit. The analysis is carried out using s physically based models of groundwater flow (MOFLOW-2000) and surface hydrology (TOPKAPI) developed for the Maggia Valley in Southern Switzerland. Calibration and sensitivity analysis were performed using UCODE_2005. Sensitivity analysis is used to identify the most important observations for both the individual and coupled models. As expected, the observations belonging to the hydrological model play a more significant role in the coupled calibration

  6. [Development of an analyzing system for soil parameters based on NIR spectroscopy].

    PubMed

    Zheng, Li-Hua; Li, Min-Zan; Sun, Hong

    2009-10-01

    A rapid estimation system for soil parameters based on spectral analysis was developed by using object-oriented (OO) technology. A class of SOIL was designed. The instance of the SOIL class is the object of the soil samples with the particular type, specific physical properties and spectral characteristics. Through extracting the effective information from the modeling spectral data of soil object, a map model was established between the soil parameters and its spectral data, while it was possible to save the mapping model parameters in the database of the model. When forecasting the content of any soil parameter, the corresponding prediction model of this parameter can be selected with the same soil type and the similar soil physical properties of objects. And after the object of target soil samples was carried into the prediction model and processed by the system, the accurate forecasting content of the target soil samples could be obtained. The system includes modules such as file operations, spectra pretreatment, sample analysis, calibrating and validating, and samples content forecasting. The system was designed to run out of equipment. The parameters and spectral data files (*.xls) of the known soil samples can be input into the system. Due to various data pretreatment being selected according to the concrete conditions, the results of predicting content will appear in the terminal and the forecasting model can be stored in the model database. The system reads the predicting models and their parameters are saved in the model database from the module interface, and then the data of the tested samples are transferred into the selected model. Finally the content of soil parameters can be predicted by the developed system. The system was programmed with Visual C++6.0 and Matlab 7.0. And the Access XP was used to create and manage the model database. PMID:20038025

  7. Development of a dynamic thermal model process

    SciTech Connect

    Smith, F. R.

    1996-04-01

    A dynamic electrical-thermal modeling simulation technique was developed to allow up-front design of thermal and electronic packaging with a high degree of accuracy and confidence. We are developing a hybrid multichip module output driver which controls with power MOSFET driver circuits. These MOSFET circuits will dissipate from 13 to 26 watts per driver in a physical package less than two square inches. The power dissipation plus an operating temperature range of -55{degrees} C to 100{degrees} C makes an accurate thermal package design critical. The project goal was to develop a simulation process to dynamically model the electrical/thermal characteristics of the power MOSFETS using the SABER analog simulator and the ABAQUS finite element simulator. SABER would simulate the electrical characteristics of the multi-chip module design while co-simulation is being done with ABAQUS simulating the solid model thermal characteristics of the MOSFET package. The dynamic parameters, MOSFET power and chip temperature, would be actively passed between simulators to effect a coupled simulator modelling technique. The project required a development of a SABER late for the analog ASIC controller circuit, a dynamic electrical/thermal template for the IRF150 and IRF9130 power MOSFETs, a solid model of the multi-chip module package, FORTRAN code to handle I/Q between and HP755 workstation and SABER, and I/O between CRAY J90 computer and ABAQUS. The simulation model was certified by measured electrical characteristics of the circuits and real time thermal imaging of the output multichip module.

  8. Development of novel microencapsulation processes

    NASA Astrophysics Data System (ADS)

    Yin, Weisi

    of polymer solution suspended in water or from a spray. Hollow PS particles were obtained by swelling PS latex with solvent, freezing in liquid nitrogen, and drying in vacuum. It is shown that the particle morphology is due to phase separation in the polymer emulsion droplets upon freezing in liquid nitrogen, and that morphological changes are driven largely by lowering interfacial free energy. The dried hollow particles were resuspended in a dispersing media and exposed to a plasticizer, which imparts mobility to polymer chains, to close the surface opening and form microcapsules surrounding an aqueous core. The interfacial free energy difference between the hydrophobic inside and hydrophilic outside surfaces is the major driving force for closing the hole on the surface. A controlled release biodegradable vehicle for drug was made by encapsulating procaine hydrochloride, a water-soluble drug, into the core of poly(DL-lactide) (PLA) microcapsules, which were made by the freeze-drying and subsequent closing process. The encapsulation efficiency is affected by the hollow particle morphology, amount of closing agent, exposure time, surfactant, and method of dispersing the hollow particles in water. Controlled release of procaine hydrochloride from the microcapsules into phosphate buffer was observed. The use of benign solvents dimethyl carbonate in spray/freeze-drying and CO2 for closing would eliminate concerns of residual harmful solvent in the product. The ease of separation of CO2 from the drug solution may also enable recycling of the drug solution to increase the overall encapsulation efficiency using these novel hollow particles.

  9. Optimization of cold rolling process parameters in order to increasing rolling speed limited by chatter vibrations

    PubMed Central

    Heidari, Ali; Forouzan, Mohammad R.

    2012-01-01

    Chatter has been recognized as major restriction for the increase in productivity of cold rolling processes, limiting the rolling speed for thin steel strips. It is shown that chatter has close relation with rolling conditions. So the main aim of this paper is to attain the optimum set points of rolling to achieve maximum rolling speed, preventing chatter to occur. Two combination methods were used for optimization. First method is done in four steps: providing a simulation program for chatter analysis, preparing data from simulation program based on central composite design of experiment, developing a statistical model to relate system tendency to chatter and rolling parameters by response surface methodology, and finally optimizing the process by genetic algorithm. Second method has analogous stages. But central composite design of experiment is replaced by Taguchi method and response surface methodology is replaced by neural network method. Also a study on the influence of the rolling parameters on system stability has been carried out. By using these combination methods, new set points were determined and significant improvement achieved in rolling speed. PMID:25685398

  10. Optimization of cold rolling process parameters in order to increasing rolling speed limited by chatter vibrations.

    PubMed

    Heidari, Ali; Forouzan, Mohammad R

    2013-01-01

    Chatter has been recognized as major restriction for the increase in productivity of cold rolling processes, limiting the rolling speed for thin steel strips. It is shown that chatter has close relation with rolling conditions. So the main aim of this paper is to attain the optimum set points of rolling to achieve maximum rolling speed, preventing chatter to occur. Two combination methods were used for optimization. First method is done in four steps: providing a simulation program for chatter analysis, preparing data from simulation program based on central composite design of experiment, developing a statistical model to relate system tendency to chatter and rolling parameters by response surface methodology, and finally optimizing the process by genetic algorithm. Second method has analogous stages. But central composite design of experiment is replaced by Taguchi method and response surface methodology is replaced by neural network method. Also a study on the influence of the rolling parameters on system stability has been carried out. By using these combination methods, new set points were determined and significant improvement achieved in rolling speed. PMID:25685398

  11. A split-optimization approach for obtaining multiple solutions in single-objective process parameter optimization.

    PubMed

    Rajora, Manik; Zou, Pan; Yang, Yao Guang; Fan, Zhi Wen; Chen, Hung Yi; Wu, Wen Chieh; Li, Beizhi; Liang, Steven Y

    2016-01-01

    It can be observed from the experimental data of different processes that different process parameter combinations can lead to the same performance indicators, but during the optimization of process parameters, using current techniques, only one of these combinations can be found when a given objective function is specified. The combination of process parameters obtained after optimization may not always be applicable in actual production or may lead to undesired experimental conditions. In this paper, a split-optimization approach is proposed for obtaining multiple solutions in a single-objective process parameter optimization problem. This is accomplished by splitting the original search space into smaller sub-search spaces and using GA in each sub-search space to optimize the process parameters. Two different methods, i.e., cluster centers and hill and valley splitting strategy, were used to split the original search space, and their efficiency was measured against a method in which the original search space is split into equal smaller sub-search spaces. The proposed approach was used to obtain multiple optimal process parameter combinations for electrochemical micro-machining. The result obtained from the case study showed that the cluster centers and hill and valley splitting strategies were more efficient in splitting the original search space than the method in which the original search space is divided into smaller equal sub-search spaces. PMID:27625978

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

    PubMed Central

    Parida, Arun Kumar; Routara, Bharat Chandra

    2014-01-01

    Taguchi's design of experiment is utilized to optimize the process parameters in turning operation with dry environment. Three parameters, cutting speed (v), feed (f), and depth of cut (d), with three different levels are taken for the responses like material removal rate (MRR) and surface roughness (Ra). The machining is conducted with Taguchi L9 orthogonal array, and based on the S/N analysis, the optimal process parameters for surface roughness and MRR are calculated separately. Considering the larger-the-better approach, optimal process parameters for material removal rate are cutting speed at level 3, feed at level 2, and depth of cut at level 3, that is, v3-f2-d3. Similarly for surface roughness, considering smaller-the-better approach, the optimal process parameters are cutting speed at level 1, feed at level 1, and depth of cut at level 3, that is, v1-f1-d3. Results of the main effects plot indicate that depth of cut is the most influencing parameter for MRR but cutting speed is the most influencing parameter for surface roughness and feed is found to be the least influencing parameter for both the responses. The confirmation test is conducted for both MRR and surface roughness separately. Finally, an attempt has been made to optimize the multiresponses using technique for order preference by similarity to ideal solution (TOPSIS) with Taguchi approach. PMID:27437503

  13. Plant parameters for plant functional groups of western rangelands to enable process-based simulation modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Regional environmental assessments with process-based models require realistic estimates of plant parameters for the primary plant functional groups in the region. “Functional group” in this context is an operational term, based on similarities in plant type and in plant parameter values. Likewise...

  14. Comparison of Perfusion- and Diffusion-weighted Imaging Parameters in Brain Tumor Studies Processed Using Different Software Platforms

    PubMed Central

    Milchenko, Mikhail V.; Rajderkar, Dhanashree; LaMontagne, Pamela; Massoumzadeh, Parinaz; Bogdasarian, Ronald; Schweitzer, Gordon; Benzinger, Tammie; Marcus, Dan; Shimony, Joshua S.; Fouke, Sarah Jost

    2015-01-01

    Rationale and Objectives To compare quantitative imaging parameter measures from diffusion- and perfusion-weighted imaging magnetic resonance imaging (MRI) sequences in subjects with brain tumors that have been processed with different software platforms. Materials and Methods Scans from 20 subjects with primary brain tumors were selected from the Comprehensive Neuro-oncology Data Repository at Washington University School of Medicine (WUSM) and the Swedish Neuroscience Institute. MR images were coregistered, and each subject's data set was processed by three software packages: 1) vendor-specific scanner software, 2) research software developed at WUSM, and 3) a commercially available, Food and Drug Administration–approved, processing platform (Nordic Ice). Regions of interest (ROIs) were chosen within the brain tumor and normal nontumor tissue. The results obtained using these methods were compared. Results For diffusion parameters, including mean diffusivity and fractional anisotropy, concordance was high when comparing different processing methods. For perfusion-imaging parameters, a significant variance in cerebral blood volume, cerebral blood flow, and mean transit time (MTT) values was seen when comparing the same raw data processed using different software platforms. Correlation was better with larger ROIs (radii ≥ 5 mm). Greatest variance was observed in MTT. Conclusions Diffusion parameter values were consistent across different software processing platforms. Perfusion parameter values were more variable and were influenced by the software used. Variation in the MTT was especially large suggesting that MTT estimation may be unreliable in tumor tissues using current MRI perfusion methods. PMID:25088833

  15. Spheronization of solid lipid extrudates: A novel approach on controlling critical process parameters.

    PubMed

    Petrovick, Gustavo Freire; Pein, Miriam; Thommes, Markus; Breitkreutz, Jörg

    2015-05-01

    Solid lipids are non-toxic excipients, which are known to potentially enhance delivery and bioavailability of poorly water-soluble drugs and moreover to mask unpleasant tasting drugs. Multiple unit matrix dosage forms based on solid lipids, such as lipid pellets, can be obtained by solvent-free cold extrusion and spheronization. This method presents advantages in the processing of sensitive substances, such as low process temperatures, the absence of solvents and a drying step. However, the material temperature during the spheronization showed to be critical so far. The process leads to increased material temperatures, causing particle agglomeration and discontinuity of the spheronization. In the present study, extrudates of 0.5mm in diameter containing metformin hydrochloride, and either semisynthetic hard fat (Witocan® 42/44) or different ternary mixtures based on hard fat, glyceryl trimyristate, and glyceryl distearate, were spheronized. By applying common process parameters, particle agglomeration or material stickiness on equipment walls was observed in preliminary experiments after 2-6min, depending on the lipid composition. Therefore, an innovative instrumental setup to control the spheronization process was developed utilizing an infrared light source, which was positioned over the particle bed. The new approach enabled a spheronization process that reached the desired spheronization temperature after 2-3min and neither particle agglomeration nor material adherence occurred even after longer process times. The different formulations, even those based on high amount of solid lipids, were successfully spheronized over 15min, resulting in small diameter lipid pellets with smooth surface and aspect ratios below 1.3. PMID:25681745

  16. Optimizing Parameters of Process-Based Terrestrial Ecosystem Model with Particle Filter

    NASA Astrophysics Data System (ADS)

    Ito, A.

    2014-12-01

    Present terrestrial ecosystem models still contain substantial uncertainties, as model intercomparison studies have shown, because of poor model constraint by observational data. So, development of advanced methodology of data-model fusion, or data-assimilation, is an important task to reduce the uncertainties and improve model predictability. In this study, I apply the Particle filter (or Sequential Monte Carlo filer) to optimize parameters of a process-based terrestrial ecosystem model (VISIT). The Particle filter is one of the data-assimilation methods, in which probability distribution of model state is approximated by many samples of parameter set (i.e., particle). This is a computationally intensive method and applicable to nonlinear systems; this is an advantage of the method in comparison with other techniques like Ensemble Kalman filter and variational method. At several sites, I used flux measurement data of atmosphere-ecosystem CO2 exchange in sequential and non-sequential manners. In the sequential data assimilation, a time-series data at 30-min or daily steps were used to optimize gas-exchange-related parameters; this method would be also effective to assimilate satellite observational data. On the other hand, in the non-sequential case, annual or long-term mean budget was adjusted to observations; this method would be also effective to assimilate carbon stock data. Although there remain technical issues (e.g., appropriate number of particles and likelihood function), I demonstrate that the Partile filter is an effective method of data-assimilation for process-based models, enhancing collaboration between field and model researchers.

  17. Productivity of Syntactic Forms as a Parameter in Language Development.

    ERIC Educational Resources Information Center

    Hass, Wilbur A.

    The author raises the question of what one can say about the structure of a person's language from a sample of his speech production and urges the calculating of information theory parameters for grammatical constructions. What has to be done is to decide what construction to focus on and what types to recognize as exemplifying that construction.…

  18. Optimization of image process parameters through factorial experiments using a flat panel detector

    NASA Astrophysics Data System (ADS)

    Norrman, Eva; Geijer, Håkan; Persliden, Jan

    2007-09-01

    In the optimization process of lumbar spine examinations, factorial experiments were performed addressing the question of whether the effective dose can be reduced and the image quality maintained by adjusting the image processing parameters. A 2k-factorial design was used which is a systematic and effective method of investigating the influence of many parameters on a result variable. Radiographic images of a Contrast Detail phantom were exposed using the default settings of the process parameters for lumbar spine examinations. The image was processed using different settings of the process parameters. The parameters studied were ROI density, gamma, detail contrast enhancement (DCE), noise compensation, unsharp masking and unsharp masking kernel (UMK). The images were computer analysed and an image quality figure (IQF) was calculated and used as a measurement of the image quality. The parameters with the largest influence on image quality were noise compensation, unsharp masking, unsharp masking kernel and detail contrast enhancement. There was an interaction between unsharp masking and kernel indicating that increasing the unsharp masking improved the image quality when combined with a large kernel size. Combined with a small kernel size however the unsharp masking had a deteriorating effect. Performing a factorial experiment gave an overview of how the image quality was influenced by image processing. By adjusting the level of noise compensation, unsharp masking and kernel, the IQF was improved to a 30% lower effective dose.

  19. Investigations on postural stability and spatiotemporal parameters of human gait using developed wearable smart insole.

    PubMed

    Das, Ratan; Kumar, Neelesh

    2015-01-01

    Measurement of spatiotemporal parameters of human gait is important for designing new, intelligent and efficient prosthetic and orthotic devices. The paper presents a novel application of smart insole for measuring force generated at various pressure points during dynamic gait on a human foot. Besides recording and analysing the spatiotemporal parameters during stance phase, the developed sensor is also used for development of active orthotic devices. Data from the sensors is analysed in LabVIEW software for detection of plantar force and temporal gait parameters. The smart instrumentation allows processing, display and storage of gait parameters and gait events in real time. Variations of pressure pattern reported by gait experiments can also be used in identifying an accidental fall. This information will be used as a feedback signal for controlling the motion of an indigenously developed gait assistive device, i.e. an active orthotic device. Pressure at the heel and great toe points is higher than the metatarsal heads during dynamic walk. It is higher at the heel and metatarsals points than the toe point during standing position. PMID:25350821

  20. Evolution of Fractal Parameters through Development Stage of Soil Crust

    NASA Astrophysics Data System (ADS)

    Ospina, Abelardo; Florentino, Adriana; Tarquis, Ana Maria

    2016-04-01

    Soil surface characteristics are subjected to changes driven by several interactions between water, air, biotic and abiotic components. One of the examples of such interactions is provided through biological soil crusts (BSC) in arid and semi-arid environments. BSC are communities composed of cyanobacteria, fungi, mosses, lichens, algae and liverworts covering the soil surface and play an important role in ecosystem functioning. The characteristics and formation of these BSC influence the soil hydrological balance, control the mass of eroded sediment, increase stability of soil surface, and influence plant productivity through the modification of nitrogen and carbon cycle. The site of this work is located at Quibor and Ojo de Agua (Lara state, Venezuela). The Quibor Depression in Venezuela is a major agricultural area being at semi-arid conditions and limited drainage favor the natural process of salinization. Additionally, the extension and intensification of agriculture has led to over-exploitation of groundwater in the past 30 years (Méndoza et al., 2013). The soil microbial crust develops initially on physical crusts which are mainly generated since wetting and drying, being a recurrent feature in the Quíbor arid zone. The microbiotic crust is organic, composed of macro organisms (bryophytes and lichens) and microorganisms (cyanobacteria, fungi algae, etc.); growing on the ground, forming a thickness no greater than 3 mm. For further details see Toledo and Florentino (2009). This study focus on characterize the development stage of the BSC based on image analysis. To this end, grayscale images of different types of biological soil crust at different stages where taken, each image corresponding to an area of 12.96 cm2 with a resolution of 1024x1024 pixels (Ospina et al., 2015). For each image lacunarity and fractal dimension through the differential box counting method were calculated. These were made with the software ImageJ/Fraclac (Karperien, 2013

  1. Development of a reburning boiler process model

    SciTech Connect

    Wu, K.T.

    1992-01-30

    The overall objective of this program is to integrate EER's expertise in boiler reburning performance evaluation into a package of analytical computer tools. Specific objectives of the program are to develop a computational capability with the following features: (1) can be used to predict the impact of gas reburning application on thermal conditions in the boiler radiant furnace, and on overall boiler performance; (2) can estimate gas reburning NO{sub x} reduction effectiveness based on specific reburning configurations and furnace/boiler configurations; (3) can be used as an analytical tool to evaluate the impact of boiler process parameters (e.g., fuel switching and changes in boiler operating conditions) on boiler thermal performance; (4) is adaptable to most boiler designs (tangential and wall fire boilers) and a variety of fuels (solid, liquid, gaseous and slurried fuels); (5) is sufficiently user friendly to be exercisable by engineers with a reasonable knowledge of boilers, and with reasonable computer skills. Here, user friendly'' means that the user will be guided by computer codes during the course of setting up individual input files for the boiler performance model.

  2. HESS Opinions: Advocating process modeling and de-emphasizing parameter estimation

    NASA Astrophysics Data System (ADS)

    Bahremand, Abdolreza

    2016-04-01

    Since its origins as an engineering discipline, with its widespread use of "black box" (empirical) modeling approaches, hydrology has evolved into a scientific discipline that seeks a more "white box" (physics-based) modeling approach to solving problems such as the description and simulation of the rainfall-runoff responses of a watershed. There has been much recent debate regarding the future of the hydrological sciences, and several publications have voiced opinions on this subject. This opinion paper seeks to comment and expand upon some recent publications that have advocated an increased focus on process-based modeling while de-emphasizing the focus on detailed attention to parameter estimation. In particular, it offers a perspective that emphasizes a more hydraulic (more physics-based and less empirical) approach to development and implementation of hydrological models.

  3. HESS Opinions: Advocating process modeling and de-emphasizing parameter estimation

    NASA Astrophysics Data System (ADS)

    Bahremand, A.

    2015-11-01

    Since the origins of hydrology as an engineering discipline, where "black box" modelling approaches were common, it has evolved into a scientific discipline that seeks a more "white box" modelling approach to solving problems such as description and simulation of the rainfall-runoff responses of a watershed. There has been much recent debate regarding the future of the hydrological sciences, and several publications have voiced opinions on this subject. This opinion paper seeks to comment and expand on some recent publications that have advocated an increased focus on process modelling while de-emphasizing the focus on detailed attention to parameter estimation. In particular, it offers a perspective that emphasizes a more hydraulic (more physics and less conceptual) approach to development and implementation of hydrological models.

  4. Selection of process parameters for producing high quality defatted sesame flour at pilot scale.

    PubMed

    Manikantan, M R; Sharma, Rajiv; Yadav, D N; Gupta, R K

    2015-03-01

    The present work was undertaken to study the effect of pearling duration, soaking time, steaming duration and drying temperature on the quality of sesame seeds and mechanically extracted partially defatted sesame cake. On the basis of quality attributes i.e. high protein, low crude fibre, low residual oil and low oxalic acid, the optimum process parameters were selected. The combination of 20 min of pearling duration, 15 min of soaking, 15 min of steaming at 100 kPa pressure and drying at 50 °C yielded high quality partially defatted protein rich sesame flour as compared to untreated defatted sesame flour. The developed high quality partially defatted protein rich sesame flour may be used in various food applications as a vital ingredient to increase the nutritional significance of the prepared foodstuffs. PMID:25745256

  5. Parametric Appraisal of Process Parameters for Adhesion of Plasma Sprayed Nanostructured YSZ Coatings Using Taguchi Experimental Design

    PubMed Central

    Mantry, Sisir; Mishra, Barada K.; Chakraborty, Madhusudan

    2013-01-01

    This paper presents the application of the Taguchi experimental design in developing nanostructured yittria stabilized zirconia (YSZ) coatings by plasma spraying process. This paper depicts dependence of adhesion strength of as-sprayed nanostructured YSZ coatings on various process parameters, and effect of those process parameters on performance output has been studied using Taguchi's L16 orthogonal array design. Particle velocities prior to impacting the substrate, stand-off-distance, and particle temperature are found to be the most significant parameter affecting the bond strength. To achieve retention of nanostructure, molten state of nanoagglomerates (temperature and velocity) has been monitored using particle diagnostics tool. Maximum adhesion strength of 40.56 MPa has been experimentally found out by selecting optimum levels of selected factors. The enhanced bond strength of nano-YSZ coating may be attributed to higher interfacial toughness due to cracks being interrupted by adherent nanozones. PMID:24288490

  6. Inverse sequential detection of parameter changes in developing time series

    NASA Technical Reports Server (NTRS)

    Radok, Uwe; Brown, Timothy J.

    1992-01-01

    Progressive values of two probabilities are obtained for parameter estimates derived from an existing set of values and from the same set enlarged by one or more new values, respectively. One probability is that of erroneously preferring the second of these estimates for the existing data ('type 1 error'), while the second probability is that of erroneously accepting their estimates for the enlarged test ('type 2 error'). A more stable combined 'no change' probability which always falls between 0.5 and 0 is derived from the (logarithmic) width of the uncertainty region of an equivalent 'inverted' sequential probability ratio test (SPRT, Wald 1945) in which the error probabilities are calculated rather than prescribed. A parameter change is indicated when the compound probability undergoes a progressive decrease. The test is explicitly formulated and exemplified for Gaussian samples.

  7. Optimization of residual stresses in MMC's through the variation of interfacial layer architectures and processing parameters

    NASA Technical Reports Server (NTRS)

    Pindera, Marek-Jerzy; Salzar, Robert S.

    1996-01-01

    The objective of this work was the development of efficient, user-friendly computer codes for optimizing fabrication-induced residual stresses in metal matrix composites through the use of homogeneous and heterogeneous interfacial layer architectures and processing parameter variation. To satisfy this objective, three major computer codes have been developed and delivered to the NASA-Lewis Research Center, namely MCCM, OPTCOMP, and OPTCOMP2. MCCM is a general research-oriented code for investigating the effects of microstructural details, such as layered morphology of SCS-6 SiC fibers and multiple homogeneous interfacial layers, on the inelastic response of unidirectional metal matrix composites under axisymmetric thermomechanical loading. OPTCOMP and OPTCOMP2 combine the major analysis module resident in MCCM with a commercially-available optimization algorithm and are driven by user-friendly interfaces which facilitate input data construction and program execution. OPTCOMP enables the user to identify those dimensions, geometric arrangements and thermoelastoplastic properties of homogeneous interfacial layers that minimize thermal residual stresses for the specified set of constraints. OPTCOMP2 provides additional flexibility in the residual stress optimization through variation of the processing parameters (time, temperature, external pressure and axial load) as well as the microstructure of the interfacial region which is treated as a heterogeneous two-phase composite. Overviews of the capabilities of these codes are provided together with a summary of results that addresses the effects of various microstructural details of the fiber, interfacial layers and matrix region on the optimization of fabrication-induced residual stresses in metal matrix composites.

  8. Modifying welding process parameters can reduce the neurotoxic potential of manganese-containing welding fumes.

    PubMed

    Sriram, Krishnan; Lin, Gary X; Jefferson, Amy M; Stone, Samuel; Afshari, Aliakbar; Keane, Michael J; McKinney, Walter; Jackson, Mark; Chen, Bean T; Schwegler-Berry, Diane; Cumpston, Amy; Cumpston, Jared L; Roberts, Jenny R; Frazer, David G; Antonini, James M

    2015-02-01

    Welding fumes (WF) are a complex mixture of toxic metals and gases, inhalation of which can lead to adverse health effects among welders. The presence of manganese (Mn) in welding electrodes is cause for concern about the potential development of Parkinson's disease (PD)-like neurological disorder. Consequently, from an occupational safety perspective, there is a critical need to prevent adverse exposures to WF. As the fume generation rate and physicochemical characteristics of welding aerosols are influenced by welding process parameters like voltage, current or shielding gas, we sought to determine if changing such parameters can alter the fume profile and consequently its neurotoxic potential. Specifically, we evaluated the influence of voltage on fume composition and neurotoxic outcome. Rats were exposed by whole-body inhalation (40 mg/m(3); 3h/day × 5 d/week × 2 weeks) to fumes generated by gas-metal arc welding using stainless steel electrodes (GMA-SS) at standard/regular voltage (25 V; RVSS) or high voltage (30 V; HVSS). Fumes generated under these conditions exhibited similar particulate morphology, appearing as chain-like aggregates; however, HVSS fumes comprised of a larger fraction of ultrafine particulates that are generally considered to be more toxic than their fine counterparts. Paradoxically, exposure to HVSS fumes did not elicit dopaminergic neurotoxicity, as monitored by the expression of dopaminergic and PD-related markers. We show that the lack of neurotoxicity is due to reduced solubility of Mn in HVSS fumes. Our findings show promise for process control procedures in developing prevention strategies for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce adverse neurological risks. PMID:25549921

  9. Modifying welding process parameters can reduce the neurotoxic potential of manganese-containing welding fumes

    PubMed Central

    Sriram, Krishnan; Lin, Gary X.; Jefferson, Amy M.; Stone, Samuel; Afshari, Aliakbar; Keane, Michael J.; McKinney, Walter; Jackson, Mark; Chen, Bean T.; Schwegler-Berry, Diane; Cumpston, Amy; Cumpston, Jared L.; Roberts, Jenny R.; Frazer, David G.; Antonini, James M.

    2015-01-01

    Welding fumes (WF) are a complex mixture of toxic metals and gases, inhalation of which can lead to adverse health effects among welders. The presence of manganese (Mn) in welding electrodes is cause for concern about the potential development of Parkinson’s disease (PD)-like neurological disorder. Consequently, from an occupational safety perspective, there is a critical need to prevent adverse exposures to WF. As the fume generation rate and physicochemical characteristics of welding aerosols are influenced by welding process parameters like voltage, current or shielding gas, we sought to determine if changing such parameters can alter the fume profile and consequently its neurotoxic potential. Specifically, we evaluated the influence of voltage on fume composition and neurotoxic outcome. Rats were exposed by whole-body inhalation (40 mg/m3; 3 h/day × 5 d/week × 2 weeks) to fumes generated by gas–metal arc welding using stainless steel electrodes (GMA-SS) at standard/regular voltage (25 V; RVSS) or high voltage (30 V; HVSS). Fumes generated under these conditions exhibited similar particulate morphology, appearing as chain-like aggregates; however, HVSS fumes comprised of a larger fraction of ultrafine particulates that are generally considered to be more toxic than their ne counterparts. Paradoxically, exposure to HVSS fumes did not elicit dopaminergic neurotoxicity, as monitored by the expression of dopaminergic and PD-related markers. We show that the lack of neurotoxicity is due to reduced solubility of Mn in HVSS fumes. Our findings show promise for process control procedures in developing prevention strategies for Mn-related neurotoxicity during welding; however, it warrants additional investigations to determine if such modifications can be suitably adapted at the workplace to avert or reduce adverse neurological risks. PMID:25549921

  10. Linear IC SPICE macromodel developed from measured transistor parameters

    SciTech Connect

    Raney, C.W.

    1991-01-01

    A transistor level model in a subcircuit definition is presented for the L161 micropower comparator. This macromodel is suitable for use with present-day circuit simulators such as PSPICE and SPICE-2G6. Wherever possible, measured transistor parameter values are used to replace default values in the models. Limitations of the macromodel and a comparison of model performance with data sheet values will be discussed. 6 refs., 1 fig., 4 tabs.

  11. Development of Processing Windows for HVOF Carbide-Based Coatings

    NASA Astrophysics Data System (ADS)

    Ang, Andrew Siao Ming; Howse, Hugo; Wade, Scott A.; Berndt, Christopher C.

    2016-01-01

    Optimized processing windows for spraying high-quality metal carbide-based coatings are developed using particle diagnostic technology. The cermet coatings were produced via the high-velocity oxygen fuel (HVOF) spray process and are proposed for service applications such as marine hydraulics. The traditional "trial and error" method for developing coating process parameters is not technically robust, as well as being costly and time consuming. Instead, this contribution investigated the use of real-time monitoring of parameters associated with the HVOF flame jets and particles using in-flight particle diagnostics. Subsequently, coatings can be produced with knowledge concerning the molten particle size, temperature, and velocity profile. The analytical results allow identification of optimized coating process windows, which translate to coatings of lower porosity and improved mechanical performance.

  12. Development of the Concise Data Processing Assessment

    ERIC Educational Resources Information Center

    Day, James; Bonn, Doug

    2011-01-01

    The Concise Data Processing Assessment (CDPA) was developed to probe student abilities related to the nature of measurement and uncertainty and to handling data. The diagnostic is a ten question, multiple-choice test that can be used as both a pre-test and post-test. A key component of the development process was interviews with students, which…

  13. Development Process for Science Operation Software

    NASA Astrophysics Data System (ADS)

    Ballester, Pascal

    2015-12-01

    Scientific software development at ESO involves defined processes for the main phases of project inception, monitoring of development performed by instrument consortia, application maintenance, and application support. We discuss the lessons learnt and evolution of the process for the next generation of tools and observing facilities.

  14. Development of High Resolution Land Surface Parameters for the Community Land Model

    SciTech Connect

    Ke, Yinghai; Leung, Lai-Yung R.; Huang, Maoyi; Coleman, Andre M.; Li, Hongyi; Wigmosta, Mark S.

    2012-11-06

    There is a growing need for high-resolution land surface parameters as land surface models are being applied at increasingly higher spatial resolution offline as well as in regional and global models. The default land surface parameters for the most recent version of the Community Land Model (i.e. CLM 4.0) are at 0.5° or coarser resolutions, released with the Community Earth System Model (CESM). Plant Functional Types (PFTs), vegetation properties such as Leaf Area Index (LAI), Stem Area Index (SAI), and non-vegetated land covers were developed using remotely sensed datasets retrieved in late 1990’s and the beginning of this century. In this study, we developed new land surface parameters for CLM 4.0, specifically PFTs, LAI, SAI and non-vegetated land cover composition, at 0.05° resolution globally based on the most recent MODIS land cover and improved MODIS LAI products. Compared to the current CLM 4.0 parameters, the new parameters produced a decreased coverage by bare soil and trees, but an increased coverage by shrub, grass, and cropland. The new parameters result in a decrease in global seasonal LAI, with the biggest decrease in boreal forests; however, the new parameters also show a large increase in LAI in tropical forest. Differences between the new and the current parameters are mainly caused by changes in the sources of remotely sensed data and the representation of land cover in the source data. Advantages and disadvantages of each dataset were discussed in order to provide guidance on the use of the data. The new high-resolution land surface parameters have been used in a coupled land-atmosphere model (WRF-CLM) applied to the western U.S. to demonstrate their use in high-resolution modeling. A remapping method from the latitude/longitude grid of the CLM data to the WRF grids with map projection was also demonstrated. Future work will include global offline CLM simulations to examine the impacts of source data resolution and subsequent land parameter

  15. Development of high resolution land surface parameters for the Community Land Model

    NASA Astrophysics Data System (ADS)

    Ke, Y.; Leung, L. R.; Huang, M.; Coleman, A. M.; Li, H.; Wigmosta, M. S.

    2012-11-01

    There is a growing need for high-resolution land surface parameters as land surface models are being applied at increasingly higher spatial resolution offline as well as in regional and global models. The default land surface parameters for the most recent version of the Community Land Model (i.e. CLM 4.0) are at 0.5° or coarser resolutions, released with the Community Earth System Model (CESM). Plant Functional Types (PFTs), vegetation properties such as Leaf Area Index (LAI), Stem Area Index (SAI), and non-vegetated land covers were developed using remotely sensed datasets retrieved in late 1990's and the beginning of this century. In this study, we developed new land surface parameters for CLM 4.0, specifically PFTs, LAI, SAI and non-vegetated land cover composition, at 0.05° resolution globally based on the most recent MODIS land cover and improved MODIS LAI products. Compared to the current CLM 4.0 parameters, the new parameters produced a decreased coverage by bare soil and trees, but an increased coverage by shrub, grass, and cropland. The new parameters result in a decrease in global seasonal LAI, with the biggest decrease in boreal forests; however, the new parameters also show a large increase in LAI in tropical forest. Differences between the new and the current parameters are mainly caused by changes in the sources of remotely sensed data and the representation of land cover in the source data. Advantages and disadvantages of each dataset were discussed in order to provide guidance on the use of the data. The new high-resolution land surface parameters have been used in a coupled land-atmosphere model (WRF-CLM) applied to the western US to demonstrate their use in high-resolution modeling. A remapping method from the latitude/longitude grid of the CLM data to the WRF grids with map projection was also demonstrated. Future work will include global offline CLM simulations to examine the impacts of source data resolution and subsequent land parameter

  16. EUV mask process specifics and development challenges

    NASA Astrophysics Data System (ADS)

    Nesladek, Pavel

    2014-07-01

    EUV lithography is currently the favorite and most promising candidate among the next generation lithography (NGL) technologies. Decade ago the NGL was supposed to be used for 45 nm technology node. Due to introduction of immersion 193nm lithography, double/triple patterning and further techniques, the 193 nm lithography capabilities was greatly improved, so it is expected to be used successfully depending on business decision of the end user down to 10 nm logic. Subsequent technology node will require EUV or DSA alternative technology. Manufacturing and especially process development for EUV technology requires significant number of unique processes, in several cases performed at dedicated tools. Currently several of these tools as e.g. EUV AIMS or actinic reflectometer are not available on site yet. The process development is done using external services /tools with impact on the single unit process development timeline and the uncertainty of the process performance estimation, therefore compromises in process development, caused by assumption about similarities between optical and EUV mask made in experiment planning and omitting of tests are further reasons for challenges to unit process development. Increased defect risk and uncertainty in process qualification are just two examples, which can impact mask quality / process development. The aim of this paper is to identify critical aspects of the EUV mask manufacturing with respect to defects on the mask with focus on mask cleaning and defect repair and discuss the impact of the EUV specific requirements on the experiments needed.

  17. Digital processing system for developing countries

    NASA Technical Reports Server (NTRS)

    Nanayakkara, C.; Wagner, H.

    1977-01-01

    An effort was undertaken to perform simple digital processing tasks using pre-existing general purpose digital computers. An experimental software package, LIGMALS, was obtained and modified for this purpose. The resulting software permits basic processing tasks to be performed including level slicing, gray mapping and ratio processing. The experience gained in this project indicates a possible direction which may be used by other developing countries to obtain digital processing capabilities.

  18. Development of Systems Engineering Model for Spent Fuel Extraction Process

    SciTech Connect

    Sun, Lijian; Royyuru, Haritha; Hsieh, Hsuan-Tsung 'Sean'; Chen, Yitung; Clarksean, Randy; Vandegrift, George; Copple, Jackie; Laidler, James

    2004-07-01

    The mission of the Transmutation Research Program (TRP) at University of Nevada, Las Vegas (UNLV) is to establish a nuclear engineering test bed that can carry out effective transmutation and advanced reactor research and development effort. The Nevada Center for Advanced Computational Methods (NCACM) at UNLV is currently developing the systems engineering model, TRPSEMPro (Transmutation Research Program System Engineering Model Project, that provides process optimization through the automatic adjustment on input parameters, such as feed compositions, stages, flow rates, etc., based on the extraction efficiency of components and concerned output factors. An object-oriented programming (OOP) is considered. Such systems engineering model consists of task manager, task integration and solution monitor modules. A MS SQL server database is implemented for managing data flow from optimization processing. Task manager coordinates and interacts with other two modules. Task integration module works as a flowsheet constructor that builds task hierarchy, input parameter values and constrains. Task solution monitor component presents both in-progress and final outputs in tabulated and graphical formats. The system can monitor parameter justification outputs from optimization toolbox developed by Mathworks' MatLab commercial software. While initial parameter constraint identifications for using optimization process is tedious and time-consuming, the interface also provides a multiple-run process that executes a design matrix without invoking any optimization module. Experimental reports can be flexibly generated through database query and formatting. (authors)

  19. DEVELOPING AND QUANTIFYING PARAMETERS FOR CLOSURE WELDING OVERPACKS CONTAINING RESEARCH REACTOR SPENT NUCLEAR FUEL AT HANFORD

    SciTech Connect

    CANNELL GR

    2007-11-07

    Fluor engineers developed a Gas Tungsten Arc Welding (GTAW) technique and parameters, demonstrated requisite weld quality and successfully closure-welded packaged spent nuclear fuel (SNF) overpacks at the Hanford Site. This paper reviews weld development and qualification activities associated with the overpack closure-welding and provides a summary of the production campaign. The primary requirement of the closure weld is to provide leaktight confinement of the packaged material against release to the environment during interim storage (40-year design term). Required weld quality, in this case, was established through up-front development and qualification, and then verification of parameter compliance during production welding. This approach was implemented to allow for a simpler overpack design and more efficient production operations than possible with approaches using routine post-weld testing and nondestructive examination (NDE). . A series of welding trials were conducted to establish the desired welding technique and parameters. Qualification of the process included statistical evaluation and American Society of Mechanical Engineers (ASME) Section IX testing. In addition, pull testing with a weighted mockup, and thermal calculation/physical testing to identify the maximum temperature the packaged contents would be subject to during welding, was performed. Thirteen overpacks were successfully packaged and placed into interim storage. The closure-welding development activities (including pull testing and thermal analysis) provided the needed confidence that the packaged SNF overpacks could be safely handled and placed into interim storage, and remain leaktight for the duration of the storage term.

  20. Developing and Qualifying Parameters for Closure Welding Overpacks Containing Research Reactor Spent Nuclear Fuel at Hanford

    SciTech Connect

    Cannell, G.R.; Goldmann, L.H.; McCormack, R.L.

    2008-07-01

    Fluor engineers developed a Gas Tungsten Arc Welding (GTAW) technique and parameters, demonstrated requisite weld quality, and successfully closure-welded packaged spent nuclear fuel (SNF) overpacks at the Hanford Site. This paper reviews weld development and qualification activities associated with the overpack closure-welding and provides a summary of the production campaign. The primary requirement of the closure weld is to provide leak-tight confinement of the packaged material against release to the environment during interim storage (40-year design term). Required weld quality, in this case, was established through up-front development and qualification, and then verification of parameter compliance during production welding. This approach was implemented to allow for a simpler overpack design and more efficient production operations than possible with approaches using routine post-weld testing and nondestructive examination (NDE). A series of welding trials were conducted to establish the desired welding technique and parameters. Qualification of the process included statistical evaluation and American Society of Mechanical Engineers (ASME) Section IX testing. In addition, pull testing with a weighted mockup, and thermal calculation/physical testing to identify the maximum temperature the packaged contents would be subject to during welding, was performed. Thirteen overpacks were successfully packaged and placed into interim storage. The closure-welding development activities (including pull testing and thermal analysis) provided the needed confidence that the packaged SNF overpacks could be safely handled and placed into interim storage, and remain leak-tight for the duration of the storage term. (author)

  1. Gaussian processes retrieval of leaf parameters from a multi-species reflectance, absorbance and fluorescence dataset.

    PubMed

    Van Wittenberghe, Shari; Verrelst, Jochem; Rivera, Juan Pablo; Alonso, Luis; Moreno, José; Samson, Roeland

    2014-05-01

    Biochemical and structural leaf properties such as chlorophyll content (Chl), nitrogen content (N), leaf water content (LWC), and specific leaf area (SLA) have the benefit to be estimated through nondestructive spectral measurements. Current practices, however, mainly focus on a limited amount of wavelength bands while more information could be extracted from other wavelengths in the full range (400-2500nm) spectrum. In this research, leaf characteristics were estimated from a field-based multi-species dataset, covering a wide range in leaf structures and Chl concentrations. The dataset contains leaves with extremely high Chl concentrations (>100μgcm(-2)), which are seldom estimated. Parameter retrieval was conducted with the machine learning regression algorithm Gaussian Processes (GP), which is able to perform adaptive, nonlinear data fitting for complex datasets. Moreover, insight in relevant bands is provided during the development of a regression model. Consequently, the physical meaning of the model can be explored. Best estimates of SLA, LWC and Chl yielded a best obtained normalized root mean square error of 6.0%, 7.7%, 9.1%, respectively. Several distinct wavebands were chosen across the whole spectrum. A band in the red edge (710nm) appeared to be most important for the estimation of Chl. Interestingly, spectral features related to biochemicals with a structural or carbon storage function (e.g. 1090, 1550, 1670, 1730nm) were found important not only for estimation of SLA, but also for LWC, Chl or N estimation. Similar, Chl estimation was also helped by some wavebands related to water content (950, 1430nm) due to correlation between the parameters. It is shown that leaf parameter retrieval by GP regression is successful, and able to cope with large structural differences between leaves. PMID:24792473

  2. Effects of the Deslagging Process on some Physicochemical Parameters of Honey

    PubMed Central

    Ranjbar, Ali Mohammad; Sadeghpour, Omid; Khanavi, Mahnaz; Shams Ardekani, Mohammad Reza; Moloudian, Hamid; Hajimahmoodi, Mannan

    2015-01-01

    Some physicochemical parameters of honey have been introduced by the International Honey Commission to evaluate its quality and origin but processes such as heating and filtering can affect these parameters. In traditional Iranian medicine, deslagging process involves boiling honey in an equal volume of water and removing the slag formed during process. The aim of this study was to determine the effects of deslagging process on parameters of color intensity, diastase evaluation, electrical conductivity, pH, free acidity, refractive index, hydroxy methyl furfural (HMF), proline and water contents according to the International Honey Committee (IHC) standards. The results showed that deslagged honey was significantly different from control honey in terms of color intensity, pH, diastase number, HMF and proline content. It can be concluded that the new standards are needed to regulate deslagged honey. PMID:25901175

  3. Effects of the Deslagging Process on some Physicochemical Parameters of Honey.

    PubMed

    Ranjbar, Ali Mohammad; Sadeghpour, Omid; Khanavi, Mahnaz; Shams Ardekani, Mohammad Reza; Moloudian, Hamid; Hajimahmoodi, Mannan

    2015-01-01

    Some physicochemical parameters of honey have been introduced by the International Honey Commission to evaluate its quality and origin but processes such as heating and filtering can affect these parameters. In traditional Iranian medicine, deslagging process involves boiling honey in an equal volume of water and removing the slag formed during process. The aim of this study was to determine the effects of deslagging process on parameters of color intensity, diastase evaluation, electrical conductivity, pH, free acidity, refractive index, hydroxy methyl furfural (HMF), proline and water contents according to the International Honey Committee (IHC) standards. The results showed that deslagged honey was significantly different from control honey in terms of color intensity, pH, diastase number, HMF and proline content. It can be concluded that the new standards are needed to regulate deslagged honey. PMID:25901175

  4. Robot development for nuclear material processing

    SciTech Connect

    Pedrotti, L.R.; Armantrout, G.A.; Allen, D.C.; Sievers, R.H. Sr.

    1991-07-01

    The Department of Energy is seeking to modernize its special nuclear material (SNM) production facilities and concurrently reduce radiation exposures and process and incidental radioactive waste generated. As part of this program, Lawrence Livermore National Laboratory (LLNL) lead team is developing and adapting generic and specific applications of commercial robotic technologies to SNM pyrochemical processing and other operations. A working gantry robot within a sealed processing glove box and a telerobot control test bed are manifestations of this effort. This paper describes the development challenges and progress in adapting processing, robotic, and nuclear safety technologies to the application. 3 figs.

  5. Mechanistic basis for the effects of process parameters on quality attributes in high shear wet granulation.

    PubMed

    Badawy, Sherif I F; Narang, Ajit S; LaMarche, Keirnan; Subramanian, Ganeshkumar; Varia, Sailesh A

    2012-12-15

    Three model compounds were used to study the effect of process parameters on in-process critical material attributes and a final product critical quality attribute. The effect of four process parameters was evaluated using design of experiment approach. Batches were characterized for particle size distribution, density (porosity), flow, compaction, and dissolution rate. The mechanisms of the effect of process parameters on primary granule properties (size and density) were proposed. Water amount showed significant effect on granule size and density. The effect of impeller speed was dependent on the granule mechanical properties and efficiency of liquid distribution in the granulator. Blend density was found to increase rapidly during wet massing. Liquid addition rate was the least consequential factor and showed minimal impact on granule density and growth. Correlations of primary properties with granulation bulk powder properties (compaction and flow) and tablet dissolution were also identified. The effects of the process parameters on the bulk powder properties and tablet dissolution were consistent with their proposed link to primary granule properties. Understanding the impact of primary granule properties on bulk powder properties and final product critical quality attributes provides the basis for modulating granulation parameters in order to optimize product performance. PMID:22981985

  6. Morphometric parameters of living human in-vitro fertilization embryos; importance of the asynchronous division process.

    PubMed

    Roux, C; Joanne, C; Agnani, G; Fromm, M; Clavequin, M C; Bresson, J L

    1995-05-01

    A total of 304 human pronuclear zygotes and cleaved embryos from the 2- to 9-cell stages, obtained during invitro fertilization attempts, were photographed and retrospectively analysed after transfer for their morphology and size in relation to their developmental stage, using the Imagenia programme of a Biocom 500 image analyser. Morphometric parameters were calculated from the perimeters, surface measurements, theoretical diameters and circularity factors for the different structures analysed. This report provides the morphometric characteristics of living embryos. For the whole population the mean values were: 157.4 microns for the external zona pellucida diameter, 121.8 microns for the internal zona pellucida diameter, 17.9 microns for the thickness of the zona pellucida and 117.2 microns for the embryo cell mass diameter. The morphometric characteristics of the pronuclear-stage population were significantly different from the cleaved cell stages. If the zona pellucida and cell mass embryo diameters increased slowly from the 2- to 9-cell stages, embryonic external diameters were higher and zona pellucida thicknesses were lower in odd than even number blastomere embryos. Preliminary results show that in cases where implantation occurs, the embryo has a lower zona pellucida thickness. A comparison of the different embryo cell stages confirmed the existence of an asynchronous division process during early embryo development. Global results show no evidence of morphometric differences between subpopulations of the embryos according to their microscopic grading. Deviations from the normal asynchronous division process, however, appear to be a new parameter to take into account during embryo scoring.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7657766

  7. Hypertension and hematologic parameters in a community near a uranium processing facility

    SciTech Connect

    Wagner, Sara E.; Burch, James B.; Bottai, Matteo; Pinney, Susan M.; Puett, Robin; Porter, Dwayne; Vena, John E.; Hebert, James R.

    2010-11-15

    Background: Environmental uranium exposure originating as a byproduct of uranium processing can impact human health. The Fernald Feed Materials Production Center functioned as a uranium processing facility from 1951 to 1989, and potential health effects among residents living near this plant were investigated via the Fernald Medical Monitoring Program (FMMP). Methods: Data from 8216 adult FMMP participants were used to test the hypothesis that elevated uranium exposure was associated with indicators of hypertension or changes in hematologic parameters at entry into the program. A cumulative uranium exposure estimate, developed by FMMP investigators, was used to classify exposure. Systolic and diastolic blood pressure and physician diagnoses were used to assess hypertension; and red blood cells, platelets, and white blood cell differential counts were used to characterize hematology. The relationship between uranium exposure and hypertension or hematologic parameters was evaluated using generalized linear models and quantile regression for continuous outcomes, and logistic regression or ordinal logistic regression for categorical outcomes, after adjustment for potential confounding factors. Results: Of 8216 adult FMMP participants 4187 (51%) had low cumulative uranium exposure, 1273 (15%) had moderate exposure, and 2756 (34%) were in the high (>0.50 Sievert) cumulative lifetime uranium exposure category. Participants with elevated uranium exposure had decreased white blood cell and lymphocyte counts and increased eosinophil counts. Female participants with higher uranium exposures had elevated systolic blood pressure compared to women with lower exposures. However, no exposure-related changes were observed in diastolic blood pressure or hypertension diagnoses among female or male participants. Conclusions: Results from this investigation suggest that residents in the vicinity of the Fernald plant with elevated exposure to uranium primarily via inhalation exhibited

  8. Development and characterization of soil material parameters for embankment breach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the widespread use of earthen dams, the processes by which earthen embankments erode and fail when overtopped during extreme events are only imperfectly understood. Aging of these dams and the associated recent focus on dam rehabilitation has increased the need for new technology and tools ...

  9. Insight into model mechanisms through automatic parameter fitting: a new methodological framework for model development

    PubMed Central

    2014-01-01

    Background Striking a balance between the degree of model complexity and parameter identifiability, while still producing biologically feasible simulations using modelling is a major challenge in computational biology. While these two elements of model development are closely coupled, parameter fitting from measured data and analysis of model mechanisms have traditionally been performed separately and sequentially. This process produces potential mismatches between model and data complexities that can compromise the ability of computational frameworks to reveal mechanistic insights or predict new behaviour. In this study we address this issue by presenting a generic framework for combined model parameterisation, comparison of model alternatives and analysis of model mechanisms. Results The presented methodology is based on a combination of multivariate metamodelling (statistical approximation of the input–output relationships of deterministic models) and a systematic zooming into biologically feasible regions of the parameter space by iterative generation of new experimental designs and look-up of simulations in the proximity of the measured data. The parameter fitting pipeline includes an implicit sensitivity analysis and analysis of parameter identifiability, making it suitable for testing hypotheses for model reduction. Using this approach, under-constrained model parameters, as well as the coupling between parameters within the model are identified. The methodology is demonstrated by refitting the parameters of a published model of cardiac cellular mechanics using a combination of measured data and synthetic data from an alternative model of the same system. Using this approach, reduced models with simplified expressions for the tropomyosin/crossbridge kinetics were found by identification of model components that can be omitted without affecting the fit to the parameterising data. Our analysis revealed that model parameters could be constrained to a standard

  10. Cellular scanning strategy for selective laser melting: Generating reliable, optimized scanning paths and processing parameters

    NASA Astrophysics Data System (ADS)

    Mohanty, Sankhya; Hattel, Jesper H.

    2015-03-01

    Selective laser melting is yet to become a standardized industrial manufacturing technique. The process continues to suffer from defects such as distortions, residual stresses, localized deformations and warpage caused primarily due to the localized heating, rapid cooling and high temperature gradients that occur during the process. While process monitoring and control of selective laser melting is an active area of research, establishing the reliability and robustness of the process still remains a challenge. In this paper, a methodology for generating reliable, optimized scanning paths and process parameters for selective laser melting of a standard sample is introduced. The processing of the sample is simulated by sequentially coupling a calibrated 3D pseudo-analytical thermal model with a 3D finite element mechanical model. The optimized processing parameters are subjected to a Monte Carlo method based uncertainty and reliability analysis. The reliability of the scanning paths are established using cumulative probability distribution functions for process output criteria such as sample density, thermal homogeneity, etc. A customized genetic algorithm is used along with the simulation model to generate optimized cellular scanning strategies and processing parameters, with an objective of reducing thermal asymmetries and mechanical deformations. The optimized scanning strategies are used for selective laser melting of the standard samples, and experimental and numerical results are compared.

  11. Detection of dominant modelled nitrate processes with a high temporally resolved parameter sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Haas, Marcelo; Guse, Björn; Pfannerstill, Matthias; Fohrer, Nicola

    2015-04-01

    The river systems in the catchment are impacted by nutrient inputs from different sources of the landscape. The input of nitrate from agricultural areas into the river systems is related to numerous processes which occur simultaneously and influence each other permanently. These complex nitrate processes are represented in eco-hydrological models. To obtain reliable future predictions of nitrate concentrations in rivers, the nitrogen cycle needs to be reproduced accurately in these models. For complex research questions dealing with nitrate impacts, it is thus essential to better understand the nitrate process dynamics in models and to reduce the uncertainties in water quality predictions. This study aims to improve the understanding of nitrate process dynamics by using a temporal parameter sensitivity analysis, which is applied on an eco-hydrological model. With this method, the dominant model parameters are detected for each day. Thus, by deriving temporal variations in dominant model parameters, the nitrate process dynamic is investigated for phases with different conditions for nitrate transport and transformations. The results show that the sensitivity of different nitrate parameters varies temporally. These temporal dynamics in dominant parameters are explained by temporal variations in nitrate transport and plant uptake processes. An extended view on the dynamics of the temporal parameter sensitivity is obtained by analysing different modelled runoff components and nitrate pathways. Thereby, the interpretation of seasonal variations in dominant nitrate pathways is assisted and a better understanding of the role of nitrate in the environment is achieved. We conclude that this method improves the reliability of modelled nitrate processes. In this way, a better basis for recent and future scenarios of nitrate loads management is provided.

  12. Software Model Of Software-Development Process

    NASA Technical Reports Server (NTRS)

    Lin, Chi Y.; Synott, Debra J.; Levary, Reuven R.

    1990-01-01

    Collection of computer programs constitutes software tool for simulation of medium- to large-scale software-development projects. Necessary to include easily identifiable and more-readily quantifiable characteristics like costs, times, and numbers of errors. Mathematical model incorporating these and other factors of dynamics of software-development process implemented in the Software Life Cycle Simulator (SLICS) computer program. Simulates dynamics of software-development process. In combination with input and output expert software systems and knowledge-based management software system, develops information for use in managing large software-development project. Intended to aid managers in planning, managing, and controlling software-development processes by reducing uncertainties in budgets, required personnel, and schedules.

  13. Development of the smooth orthogonal decomposition method to derive the modal parameters of vehicle suspension system

    NASA Astrophysics Data System (ADS)

    Rezaee, Mousa; Shaterian-Alghalandis, Vahid; Banan-Nojavani, Ali

    2013-04-01

    In this paper, the smooth orthogonal decomposition (SOD) method is developed to the light damped systems in which the inputs are time shifted functions of one or more random processes. An example of such practical cases is the vehicle suspension system in which the random inputs due to the road roughness applied to the rear wheels are the shifted functions of the same random inputs on the front wheels with a time lag depending on the vehicle wheelbase as well as its velocity. The developed SOD method is applied to determine the natural frequencies and mode shapes of a certain vehicle suspension system and the results are compared with the true values obtained by the structural eigenvalue problem. The consistency of the results indicates that the SOD method can be applied with a high degree of accuracy to calculate the modal parameters of vibrating systems in which the system inputs are shifted functions of one or more random processes.

  14. Process parameter dependent growth phenomena of naproxen nanosuspension manufactured by wet media milling.

    PubMed

    Bitterlich, A; Laabs, C; Krautstrunk, I; Dengler, M; Juhnke, M; Grandeury, A; Bunjes, H; Kwade, A

    2015-05-01

    The production of nanosuspensions has proved to be an effective method for overcoming bioavailability challenges of poorly water soluble drugs. Wet milling in stirred media mills and planetary ball mills has become an established top-down-method for producing such drug nanosuspensions. The quality of the resulting nanosuspension is determined by the stability against agglomeration on the one hand, and the process parameters of the mill on the other hand. In order to understand the occurring dependencies, a detailed screening study, not only on adequate stabilizers, but also on their optimum concentration was carried out for the active pharmaceutical ingredient (API) naproxen in a planetary ball mill. The type and concentration of the stabilizer had a pronounced influence on the minimum particle size obtained. With the best formulation the influence of the relevant process parameters on product quality was investigated to determine the grinding limit of naproxen. Besides the well known phenomenon of particle agglomeration, actual naproxen crystal growth and morphology alterations occurred during the process which has not been observed before. It was shown that, by adjusting the process parameters, those effects could be reduced or eliminated. Thus, besides real grinding and agglomeration a process parameter dependent ripening of the naproxen particles was identified to be a concurrent effect during the naproxen fine grinding process. PMID:25766272

  15. Optimization of processing parameters and metrology for novel NCA negative resists for NGL

    NASA Astrophysics Data System (ADS)

    Singh, Vikram; Satyanarayana, V. S. V.; Kessler, Felipe; Scheffer, Francine R.; Weibel, Daniel E.; Sharma, Satinder K.; Ghosh, Subrata; Gonsalves, Kenneth E.

    2014-04-01

    It is expected that EUV resists must simultaneously pattern 20-nm half-pitch and below, with an LWR of <1.8 nm, and a sensitivity of 5-20 mJ/cm2. In order to make a resist perform optimally, new resist chemistry is required. One such approach being investigated by us is the development of polymeric non-CAR negative photo resists for sub 16 nm technology which is directly sensitive to radiation without utilizing the concept of chemical amplification (CARs). These resist designs are accomplished by homopolymers which are prepared from monomers containing sulfonium groups. We have achieved 20 nm patterns by e-beam lithography using this system. Here we will discuss in detail process parameters such as: spinning conditions for film thicknesses <50 nm and resulting surface topographies, baking regimes, exposure conditions and protocols on sensitivity, contrast, resolution and LER/LWR. Etch resistance data on these thin films will also be provided. Our results are aimed to provide a clear understanding of how these critical steps in the lithographic imaging process will affect extendibility of the non-CAR resist concept to sub 20 nanoscale features. Photodynamics and EUV exposure data will be covered.

  16. Measles in developing countries. Part I. Epidemiological parameters and patterns.

    PubMed Central

    McLean, A. R.; Anderson, R. M.

    1988-01-01

    This paper presents a review of published data concerning the epidemiology of measles in developing countries. Simple mathematical models provide a framework for data analysis and interpretation. The analyses highlight differences and similarities in the patterns of transmission of the measles virus in developed and developing countries. Whilst the rate of loss of maternally derived immunity to measles is broadly similar, the average age at infection is much lower, and case fatality rates are much higher in developing countries. Data analysis also serves to illustrate inter-relationships between different kinds of epidemiological data. Thus, for example, in order to correctly interpret an age stratified serological profile from a developing country it is necessary to have information on the rate of decay of maternal antibodies and age specific case fatality rates. To determine the probable impact of a given vaccination programme, information on the birth rate in the community concerned is also required. A discussion is given of the epidemiological data required in order to effectively design a community based vaccination programme aimed at the eradication of measles. PMID:3338500

  17. Scaleup of IGT MILDGAS Process to a process development unit

    SciTech Connect

    Campbell, J.A.L.; Longanbach, J.; Johnson, R.; Underwood, K.; Mead, J.; Carty, R.H.

    1992-12-31

    The MILDGAS process is capable of processing both eastern caking and western non-caking coals to yield a slate of liquid and solid products. The liquids can be processed to produce: feedstocks for chemicals; pitch for use as a binder for electrodes in the aluminum industry; and fuels. Depending on the feed coal characteristics and the operating conditions, the char can be used as an improved fuel for power generation or can be used to make form coke for steel-making blast furnaces or for foundry cupola operations. The specific objectives of the program are to: design, construct, and operate a 24-tons/day adiabatic process development unit (PDU) to obtain process performance data suitable for design scaleup; obtain large batches of coal-derived co-products for industrial evaluation; prepare a detailed design of a demonstration unit; and develop technical and economic plans for commercialization of the MILDGAS process. In this paper, the authors present the process design of the PDU facility, a description of the expected product distribution and the project test plan to be implemented in the program.

  18. A Module Experimental Process System Development Unit (MEPSDU)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The purpose of this program is to demonstrate the technical readiness of a cost effective process sequence that has the potential for the production of flat plate photovoltaic modules which met the price goal in 1986 of $.70 or less per watt peak. Program efforts included: preliminary design review, preliminary cell fabrication using the proposed process sequence, verification of sandblasting back cleanup, study of resist parameters, evaluation of pull strength of the proposed metallization, measurement of contact resistance of Electroless Ni contacts, optimization of process parameter, design of the MEPSDU module, identification and testing of insulator tapes, development of a lamination process sequence, identification, discussions, demonstrations and visits with candidate equipment vendors, evaluation of proposals for tabbing and stringing machine.

  19. EUV extendibility via dry development rinse process

    NASA Astrophysics Data System (ADS)

    Sayan, Safak; Zheng, Tao; De Simone, Danilo; Vandenberghe, Geert

    2016-03-01

    Conventional photoresist processing involves resist coating, exposure, post-exposure bake, development, rinse and spin drying of a wafer. DDRP mitigates pattern collapse by applying a special polymer material (DDRM) which replaces the exposed/developed part of the photoresist material before wafer is spin dried. As noted above, the main mechanism of pattern collapse is the capillary forces governed by surface tension of rinse water and its asymmetrical recession from both sides of the lines during the drying step of the develop process. DDRP essentially eliminates these failure mechanisms by replacing remaining rinse water with DDRM and providing a structural framework that support resist lines from both sides during spin dry process. Dry development rinse process (DDRP) eliminates the root causes responsible for pattern collapse of photoresist line structures. Since these collapse mechanisms are mitigated, without the need for changes in the photoresist itself, achievable resolution of the state-of-the-art EUV photoresists can further be improved.

  20. Effects of process parameters on the molding quality of the micro-needle array

    NASA Astrophysics Data System (ADS)

    Qiu, Z. J.; Ma, Z.; Gao, S.

    2016-07-01

    Micro-needle array, which is used in medical applications, is a kind of typical injection molded products with microstructures. Due to its tiny micro-features size and high aspect ratios, it is more likely to produce short shots defects, leading to poor molding quality. The injection molding process of the micro-needle array was studied in this paper to find the effects of the process parameters on the molding quality of the micro-needle array and to provide theoretical guidance for practical production of high-quality products. With the shrinkage ratio and warpage of micro needles as the evaluation indices of the molding quality, the orthogonal experiment was conducted and the analysis of variance was carried out. According to the results, the contribution rates were calculated to determine the influence of various process parameters on molding quality. The single parameter method was used to analyse the main process parameter. It was found that the contribution rate of the holding pressure on shrinkage ratio and warpage reached 83.55% and 94.71% respectively, far higher than that of the other parameters. The study revealed that the holding pressure is the main factor which affects the molding quality of micro-needle array so that it should be focused on in order to obtain plastic parts with high quality in the practical production.

  1. A two-parameter stochastic process for Dansgaard-Oeschger events

    NASA Astrophysics Data System (ADS)

    Braun, H.; Ditlevsen, P.; Kurths, J.; Mudelsee, M.

    2011-09-01

    Various climatic processes are thought to evolve as rapid, shift-like events, which points at the presence of nonlinear dynamics. Time series analysis of nonlinear processes, however, is not trivial, for example, because of the difficulty in coming up with a realistic random process as a viable null hypothesis. In this methodology paper we construct a basic two-parameter process of shift-like excursions in an excitable system with a threshold. We demonstrate that this stochastic process, in comparison with a specific one-parameter process, can better reproduce main features of the waiting time histogram of abrupt glacial climate events, the Dansgaard-Oeschger events, as seen in two paleoclimatic proxy records, the North Greenland Ice core Project (NGRIP) ice core and the Sofular stalagmite δ18O records. We use the two-parameter process to test some arguments that were proposed in the ongoing discussion of a possible solar role in triggering Dansgaard-Oeschger events. Using our approach, we suggest for future studies to generate time series of random events which can serve as a more plausible null hypothesis for Monte Carlo based statistical tests on the regularity of shift-like processes such as Dansgaard-Oeschger events.

  2. WRAP process area development control work plan

    SciTech Connect

    Leist, K.L., Fluor Daniel Hanford

    1997-02-27

    This work plan defines the manner in which the Waste Receiving and Processing Facility, Module I Process Area will be maintained under development control status. This status permits resolution of identified design discrepancies, control system changes, as-building of equipment, and perform modifications to increase process operability and maintainability as parallel efforts. This work plan maintains configuration control as these efforts are undertaken. This task will end with system testing and reissue of field verified design drawings.

  3. The effects of process parameters on injection-molded PZT ceramics part fabrication- compounding process rheology.

    SciTech Connect

    Halbleib, Laura L.; Yang, Pin; Mondy, Lisa Ann; Burns, George Robert

    2005-05-01

    Solid solutions of lead-based perovskites are the backbone materials of the piezoelectric components for transducer, actuator, and resonator applications. These components, typically small in size, are fabricated from large sintered ceramic slugs using grinding and lapping processes. These operations increase manufacturing costs and produce a large hazardous waste stream, especially when component size decreases. To reduce costs and hazardous wastes associated with the production of these components, an injection molding technique is being investigated to replace the machining processes. The first step in the new technique is to compound an organic carrier with a ceramic powder. The organic carrier is a thermoplastic based system composed of a main carrier, a binder, and a surfactant. Understanding the rheology of the compounded material is necessary to minimize the creation of defects such as voids or cavities during the injection-molding process. An experiment was performed to model the effects of changes in the composition and processing of the material on the rheological behavior. Factors studied included: the surfactant of the organic carrier system, the solid loading of the compounded material, and compounding time. The effects of these factors on the viscosity of the material were investigated.

  4. Course Development: Industrial or Social Process.

    ERIC Educational Resources Information Center

    Kaufman, David

    The development of course materials at the Open Learning Institute, British Columbia, Canada, is examined from two perspectives: as an industrial process and as a social process. The public institute provides distance education through paced home-study courses. The course team model used at the Institute is a system approach. Course development…

  5. Teaching Information Systems Development via Process Variants

    ERIC Educational Resources Information Center

    Tan, Wee-Kek; Tan, Chuan-Hoo

    2010-01-01

    Acquiring the knowledge to assemble an integrated Information System (IS) development process that is tailored to the specific needs of a project has become increasingly important. It is therefore necessary for educators to impart to students this crucial skill. However, Situational Method Engineering (SME) is an inherently complex process that…

  6. A Comprehensive Process for Display Systems Development.

    ERIC Educational Resources Information Center

    Simcox, William A.

    A comprehensive development process for display design, focusing on computer-generated cathode ray tube (CRT) displays is presented. A framework is created for breaking the display into its component parts, used to guide the design process. The objective is to design or select the most cost effective graphics solution (hardware and software) to…

  7. Precision grinding process development for brittle materials

    SciTech Connect

    Blaedel, K L; Davis, P J; Piscotty, M A

    1999-04-01

    High performance, brittle materials are the materials of choice for many of today's engineering applications. This paper describes three separate precision grinding processes developed at Lawrence Liver-more National Laboratory to machine precision ceramic components. Included in the discussion of the precision processes is a variety of grinding wheel dressing, truing and profiling techniques.

  8. DOSIMETRIC AND TOXICOKINETIC PARAMETERS FOR THE DEVELOPING ORGANISM

    EPA Science Inventory

    Recently several scientific workshops and panels have highlighted the need for additional guidance on dosimetry for the developing organism (i.e., human and standard experimental laboratory species for the life stages). The EPA SAB review of the 1999 draft cancer risk assessment...

  9. Processing Parameters Optimization for Material Deposition Efficiency in Laser Metal Deposited Titanium Alloy

    NASA Astrophysics Data System (ADS)

    Mahamood, Rasheedat M.; Akinlabi, Esther T.

    2016-03-01

    Ti6Al4V is an important Titanium alloy that is mostly used in many applications such as: aerospace, petrochemical and medicine. The excellent corrosion resistance property, the high strength to weight ratio and the retention of properties at high temperature makes them to be favoured in most applications. The high cost of Titanium and its alloys makes their use to be prohibitive in some applications. Ti6Al4V can be cladded on a less expensive material such as steel, thereby reducing cost and providing excellent properties. Laser Metal Deposition (LMD) process, an additive manufacturing process is capable of producing complex part directly from the 3-D CAD model of the part and it also has the capability of handling multiple materials. Processing parameters play an important role in LMD process and in order to achieve desired results at a minimum cost, then the processing parameters need to be properly controlled. This paper investigates the role of processing parameters: laser power, scanning speed, powder flow rate and gas flow rate, on the material utilization efficiency in laser metal deposited Ti6Al4V. A two-level full factorial design of experiment was used in this investigation, to be able to understand the processing parameters that are most significant as well as the interactions among these processing parameters. Four process parameters were used, each with upper and lower settings which results in a combination of sixteen experiments. The laser power settings used was 1.8 and 3 kW, the scanning speed was 0.05 and 0.1 m/s, the powder flow rate was 2 and 4 g/min and the gas flow rate was 2 and 4 l/min. The experiments were designed and analyzed using Design Expert 8 software. The software was used to generate the optimized process parameters which were found to be laser power of 3.2 kW, scanning speed of 0.06 m/s, powder flow rate of 2 g/min and gas flow rate of 3 l/min.

  10. Effects of Process Parameters on Replication Accuracy of Microinjection Molded Cyclic Olefins Copolymers Parts

    NASA Astrophysics Data System (ADS)

    Lin, Hsuan-Liang; Chen, Chun-Sheng; Lee, Ruey-Tsung; Chen, Shia-Chung; Chien, Rean-Der; Jeng, Ming-Chang; Hwang, Jiun-Ren

    2013-04-01

    In this study, the effects of various processing parameters of microinjection molding on the replication accuracy of the micro featured fluidic platform used for DNA/RNA tests are investigated. LIGA-like processes were utilized to prepare a silicon-based SU-8 photoresist, followed by electroforming to make a Ni-Co-based stamp. A cyclic olefin copolymer (COC) was used as the injection molding material. The molding parameters associated with the replication accuracy of micro channel parts were investigated. It was found that for microinjection molded devices, the replication accuracies of the imprint width and depth increase with increasing of mold temperature, melt temperature, injection velocity, and packing pressure.

  11. Process-Based Quality (PBQ) Tools Development

    SciTech Connect

    Cummins, J.L.

    2001-12-03

    The objective of this effort is to benchmark the development of process-based quality tools for application in CAD (computer-aided design) model-based applications. The processes of interest are design, manufacturing, and quality process applications. A study was commissioned addressing the impact, current technologies, and known problem areas in application of 3D MCAD (3-dimensional mechanical computer-aided design) models and model integrity on downstream manufacturing and quality processes. The downstream manufacturing and product quality processes are profoundly influenced and dependent on model quality and modeling process integrity. The goal is to illustrate and expedite the modeling and downstream model-based technologies for available or conceptual methods and tools to achieve maximum economic advantage and advance process-based quality concepts.

  12. Silicon EFG process development by multiscale modeling

    NASA Astrophysics Data System (ADS)

    Müller, M.; Birkmann, B.; Mosel, F.; Westram, I.; Seidl, A.

    2010-04-01

    An overview of simulation models in use for optimizing the edge-defined film-fed growth (EFG) process of thin-walled hollow silicon tubes at WACKER SCHOTT Solar is presented. The simulations span the length scales from complete furnace models over growth simulations with a mesoscopic description of the crystalline character of silicon down to solidification simulations with atomic resolution. Results gained from one model are used as input parameters or boundary conditions on other levels. Examples for the application of these models and their impact on process design are given. These include the reduction of tube thickness variations, the control of tube deformations, residual stresses and dislocation densities and the identification of twin formation processes typical for EFG silicon.

  13. Variational estimation of process parameters in a simplified atmospheric general circulation model

    NASA Astrophysics Data System (ADS)

    Lv, Guokun; Koehl, Armin; Stammer, Detlef

    2016-04-01

    Parameterizations are used to simulate effects of unresolved sub-grid-scale processes in current state-of-the-art climate model. The values of the process parameters, which determine the model's climatology, are usually manually adjusted to reduce the difference of model mean state to the observed climatology. This process requires detailed knowledge of the model and its parameterizations. In this work, a variational method was used to estimate process parameters in the Planet Simulator (PlaSim). The adjoint code was generated using automatic differentiation of the source code. Some hydrological processes were switched off to remove the influence of zero-order discontinuities. In addition, the nonlinearity of the model limits the feasible assimilation window to about 1day, which is too short to tune the model's climatology. To extend the feasible assimilation window, nudging terms for all state variables were added to the model's equations, which essentially suppress all unstable directions. In identical twin experiments, we found that the feasible assimilation window could be extended to over 1-year and accurate parameters could be retrieved. Although the nudging terms transform to a damping of the adjoint variables and therefore tend to erases the information of the data over time, assimilating climatological information is shown to provide sufficient information on the parameters. Moreover, the mechanism of this regularization is discussed.

  14. Optimization of LPDC Process Parameters Using the Combination of Artificial Neural Network and Genetic Algorithm Method

    NASA Astrophysics Data System (ADS)

    Zhang, Liqiang; Li, Luoxing; Wang, Shiuping; Zhu, Biwu

    2012-04-01

    In this article, the low-pressure die-cast (LPDC) process parameters of aluminum alloy thin-walled component with permanent mold are optimized using a combining artificial neural network and genetic algorithm (ANN/GA) method. In this method, an ANN model combining learning vector quantization (LVQ) and back-propagation (BP) algorithm is proposed to map the complex relationship between process conditions and quality indexes of LPDC. The genetic algorithm is employed to optimize the process parameters with the fitness function based on the trained ANN model. Then, by applying the optimized parameters, a thin-walled component with 300 mm in length, 100 mm in width, and 1.5 mm in thickness is successfully prepared and no obvious defects such as shrinkage, gas porosity, distortion, and crack were found in the component. The results indicate that the combining ANN/GA method is an effective tool for the process optimization of LPDC, and they also provide valuable reference on choosing the right process parameters for LPDC thin-walled aluminum alloy casting.

  15. The message processing and distribution system development

    NASA Astrophysics Data System (ADS)

    Whitten, K. L.

    1981-06-01

    A historical approach is used in presenting the life cycle development of the Navy's message processing and distribution system beginning with the planning phase and ending with the integrated logistic support phase. Several maintenance problems which occurred after the system was accepted for fleet use were examined to determine if they resulted from errors in the acquisition process. The critical decision points of the acquisition process are examined and constructive recommendations are made for avoiding the problems which hindered the successful development of this system.

  16. Electropolishing process development for PWR steam generator channel heads

    SciTech Connect

    Asay, R.H.; Graves, P.; Guastaferro, C.T.; Spalaris, C.N. )

    1991-04-01

    A broad range of process parameters was established to smoothen the surface of 309 L weld clad overlay, prototypic of surfaces common is channel heads of replacement PWR (pressurized water reactor) steam generators. Mechanical and electropolishing steps were studied to explore process boundaries, which result in acceptable degree of surface smoothness, without compromising metallurgical properties. Recommended processes and acceptance criteria established in this work, can be applied to electropolish steam generator channel heads. Smooth surfaces are less likely to retain radioactive species, and potentially develop lower radiation fields when these components are placed into service. 7 refs., 11 figs., 12 tabs.

  17. Using Reflection to Develop Higher Order Processes

    ERIC Educational Resources Information Center

    Lerch, Carol; Bilics, Andrea; Colley, Binta

    2006-01-01

    The main purpose of this study was to look at how we used specific writing assignments in our courses to encourage metacognitive reflection in order to increase the learning that takes place. The study also aimed to aid in the development of higher order processing skills through the development of student reflection. The students involved in the…

  18. Information Processing Theory and Conceptual Development.

    ERIC Educational Resources Information Center

    Schroder, H. M.

    An educational program based upon information processing theory has been developed at Southern Illinois University. The integrating theme was the development of conceptual ability for coping with social and personal problems. It utilized student information search and concept formation as foundations for discussion and judgment and was organized…

  19. The Cassini-Huygens Sequence Development Process

    NASA Technical Reports Server (NTRS)

    Long, Jennifer H.; Heventhal, William M., III; Javidnia, Shahram

    2006-01-01

    Each phase of the sequence development process had to overcome many operational challenges due to the immense complexity of the spacecraft, tour design, pointing capabilities, flight rules and software development. This paper will address the specific challenges related to each of those complexities and the methods used to overcome them during operation.

  20. Cognitive Process of Development in Children

    ERIC Educational Resources Information Center

    Boddington, Eulalee N.

    2009-01-01

    In this article we explored the theories of Arnold Gesell, Erik Erickson and Jean Piaget about how human beings development. In this component we will analyze the cognitive processes of how children perceive and develop, in particular children from a cross-cultural background. How learning takes place, and how the influences of culture, and…

  1. Influence of Processing Parameters on the Flow Path in Friction Stir Welding

    NASA Technical Reports Server (NTRS)

    Schneider, J. A.; Nunes, A. C., Jr.

    2006-01-01

    Friction stir welding (FSW) is a solid phase welding process that unites thermal and mechanical aspects to produce a high quality joint. The process variables are rpm, translational weld speed, and downward plunge force. The strain-temperature history of a metal element at each point on the cross-section of the weld is determined by the individual flow path taken by the particular filament of metal flowing around the tool as influenced by the process variables. The resulting properties of the weld are determined by the strain-temperature history. Thus to control FSW properties, improved understanding of the processing parameters on the metal flow path is necessary.

  2. Effect of Process Parameters on Abnormal Grain Growth during Friction Stir Processing of a Cast Al Alloy

    SciTech Connect

    Jana, Saumyadeep; Mishra, Rajiv S.; Baumann, John A.; Grant, Glenn J.

    2010-11-25

    The effects of process parameters and friction stir processing (FSP) run configurations on the stability of nugget microstructure at elevated temperatures were evaluated. Cast plates of an Al-7Si- 0.6Mg alloy were friction stir processed using a combination of tool rotation rates and tool traverse speeds. All single pass runs showed some extent of abnormal grain growth (AGG), whereas multi-pass runs were more resistant to AGG. Additionally, higher tool rpm was found to be beneficial for controlling AGG. These effects were analyzed by comparing the result of this work with other published results and AGG models.

  3. Analysis of parameter and interaction between parameter of the microwave assisted transesterification process of coconut oil using response surface methodology

    NASA Astrophysics Data System (ADS)

    Hidayanti, Nur; Suryanto, A.; Qadariyah, L.; Prihatini, P.; Mahfud, Mahfud

    2015-12-01

    A simple batch process was designed for the transesterification of coconut oil to alkyl esters using microwave assisted method. The product with yield above 93.225% of alkyl ester is called the biodiesel fuel. Response surface methodology was used to design the experiment and obtain the maximum possible yield of biodiesel in the microwave-assisted reaction from coconut oil with KOH as the catalyst. The results showed that the time reaction and concentration of KOH catalyst have significant effects on yield of alkyl ester. Based on the response surface methodology using the selected operating conditions, the time of reaction and concentration of KOH catalyst in transesterification process were 150 second and 0.25%w/w, respectively. The largest predicted and experimental yield of alkyl esters (biodiesel) under the optimal conditions are 101.385% and 93.225%, respectively. Our findings confirmed the successful development of process for the transesterification reaction of coconut oil by microwave-assisted heating, which is effective and time-saving for alkyl ester production.

  4. A Study on Reactive Spray Deposition Technology Processing Parameters in the Context of Pt Nanoparticle Formation

    NASA Astrophysics Data System (ADS)

    Roller, Justin M.; Maric, Radenka

    2015-12-01

    Catalytic materials are complex systems in which achieving the desired properties (i.e., activity, selectivity and stability) depends on exploiting the many degrees of freedom in surface and bulk composition, geometry, and defects. Flame aerosol synthesis is a process for producing nanoparticles with ample processing parameter space to tune the desired properties. Flame dynamics inside the reactor are determined by the input process variables such as solubility of precursor in the fuel; solvent boiling point; reactant flow rate and concentration; flow rates of air, fuel and the carrier gas; and the burner geometry. In this study, the processing parameters for reactive spray deposition technology, a flame-based synthesis method, are systematically evaluated to understand the residence times, reactant mixing, and temperature profiles of flames used in the synthesis of Pt nanoparticles. This provides a framework for further study and modeling. The flame temperature and length are also studied as a function of O2 and fuel flow rates.

  5. 450mm etch process development and process chamber evaluation using 193i DSA guided pattern

    NASA Astrophysics Data System (ADS)

    Collison, Wenli; Lin, Yii-Cheng; Dunn, Shannon; Takikawa, Hiroaki; Paris, James; Chen, Lucy; Detrick, Troy; Belen, Jun; Stojakovic, George; Goss, Michael; Fish, Norman; Park, Minjoon; Sun, Chih-Ming; Kelling, Mark; Lin, Pinyen

    2016-03-01

    In the Global 450mm Equipment Development Consortium (G450C), a 193i guided directed self-assembly (DSA) pattern has been used to create structures at the 14nm node and below. The first guided DSA patterned wafer was ready for etch process development within a month of the G450C's first 193i patterned wafer availability with one litho pass. Etch processes were scaled up from 300mm to 450mm for a 28nm pitch STI stack and a 40nm pitch M1 BEOL stack. The effects of various process parameters were investigated to fine tune each process. Overall process window has been checked and compared. Excellent process stability results were shown for current etch chambers.

  6. Optimisation of Lime-Soda process parameters for reduction of hardness in aqua-hatchery practices using Taguchi methods.

    PubMed

    Yavalkar, S P; Bhole, A G; Babu, P V Vijay; Prakash, Chandra

    2012-04-01

    This paper presents the optimisation of Lime-Soda process parameters for the reduction of hardness in aqua-hatchery practices in the context of M. rosenbergii. The fresh water in the development of fisheries needs to be of suitable quality. Lack of desirable quality in available fresh water is generally the confronting restraint. On the Indian subcontinent, groundwater is the only source of raw water, having varying degree of hardness and thus is unsuitable for the fresh water prawn hatchery practices (M. rosenbergii). In order to make use of hard water in the context of aqua-hatchery, Lime-Soda process has been recommended. The efficacy of the various process parameters like lime, soda ash and detention time, on the reduction of hardness needs to be examined. This paper proposes to determine the parameter settings for the CIFE well water, which is pretty hard by using Taguchi experimental design method. Orthogonal Arrays of Taguchi, Signal-to-Noise Ratio, the analysis of variance (ANOVA) have been applied to determine their dosage and analysed for their effect on hardness reduction. The tests carried out with optimal levels of Lime-Soda process parameters confirmed the efficacy of the Taguchi optimisation method. Emphasis has been placed on optimisation of chemical doses required to reduce the total hardness using Taguchi method and ANOVA, to suit the available raw water quality for aqua-hatchery practices, especially for fresh water prawn M. rosenbergii. PMID:24749379

  7. Computer-aided software development process design

    NASA Technical Reports Server (NTRS)

    Lin, Chi Y.; Levary, Reuven R.

    1989-01-01

    The authors describe an intelligent tool designed to aid managers of software development projects in planning, managing, and controlling the development process of medium- to large-scale software projects. Its purpose is to reduce uncertainties in the budget, personnel, and schedule planning of software development projects. It is based on dynamic model for the software development and maintenance life-cycle process. This dynamic process is composed of a number of time-varying, interacting developmental phases, each characterized by its intended functions and requirements. System dynamics is used as a modeling methodology. The resulting Software LIfe-Cycle Simulator (SLICS) and the hybrid expert simulation system of which it is a subsystem are described.

  8. Effect of operating parameters on the removal of bone cement by a sawing process.

    PubMed

    James, Thomas P; Sheehan, Brian; Sagar, Amrit

    2014-03-01

    The number of total knee arthroplasty revision surgeries is increasing each year, driven by the wide availability and general acceptance of the procedure accompanied by an aging population of implants. Metal implants are often secured to the tibial plateau by a mantle of poly(methyl methacrylate) bone cement. During revision surgery, a power oscillating saw is used to remove bone cement while preparing the boney bed. Presently, there are no published studies on the mechanics of bone cement removal by a sawing process. The aim of this research was to quantify the effect of blade speed and applied thrust force on the volumetric cutting rate of bone cement. A custom reciprocating saw with variable stroke length was used to conduct a three-factor design of experiments. Two levels, without center-points, were sufficient to model the effect of stroke length (6.75, 10.13 mm), thrust force (11, 19 N), and reciprocating speed in strokes per minute (6000, 8000 SPM) on cutting rate. The results indicate that each of the three parameters had a significant impact on cutting rate (p < 0.001), with a linear relationship between both force and cutting rate (r = 0.98) and blade speed and cutting rate (r = 0.98). For the parameters considered, increasing the reciprocating speed had the most significant effect on cutting rate. For example, while holding force and stroke length constant (11 N, 10.13 mm), an increase in speed from 6000 to 8000 SPM nearly doubled the cutting rate of bone cement. A cutting rate model was developed by regression analysis of the experimental data and validated through additional experiments. The model has applications in haptic feedback for surgical simulators to differentiate between the cutting rates of bone and bone cement during virtual training of resident surgeons. PMID:24562099

  9. Adult Personality Development: Dynamics and Processes

    PubMed Central

    Diehl, Manfred; Hooker, Karen

    2013-01-01

    The focus of this special issue of Research in Human Development is on adult personality and how personality may contribute to and be involved in adult development. Specifically, the contributions in this issue focus on the links between personality structures (e.g., traits) and personality processes (e.g., goal pursuit, self--regulation) and emphasize the contributions that intensive repeated measurement approaches can make to the understanding of personality and development across the adult life span. PMID:24068889

  10. Aperiodic signals processing via parameter-tuning stochastic resonance in a photorefractive ring cavity

    SciTech Connect

    Li, Xuefeng; Cao, Guangzhan; Liu, Hongjun

    2014-04-15

    Based on solving numerically the generalized nonlinear Langevin equation describing the nonlinear dynamics of stochastic resonance by Fourth-order Runge-Kutta method, an aperiodic stochastic resonance based on an optical bistable system is numerically investigated. The numerical results show that a parameter-tuning stochastic resonance system can be realized by choosing the appropriate optical bistable parameters, which performs well in reconstructing aperiodic signals from a very high level of noise background. The influences of optical bistable parameters on the stochastic resonance effect are numerically analyzed via cross-correlation, and a maximum cross-correlation gain of 8 is obtained by optimizing optical bistable parameters. This provides a prospective method for reconstructing noise-hidden weak signals in all-optical signal processing systems.

  11. Subsonic flight test evaluation of a propulsion system parameter estimation process for the F100 engine

    NASA Technical Reports Server (NTRS)

    Orme, John S.; Gilyard, Glenn B.

    1992-01-01

    An adaptive-performance-seeking control system which optimizes the quasi-steady-state performance of the F-15 propulsion system is discussed. This paper presents flight- and ground-test evaluations of the propulsion system parameter-estimation process used by the performance seeking control system. The estimator consists of a compact propulsion system model and an extended Kalman filter. The extended Kalman filter estimates five engine component deviation parameters from measured inputs. The compact model uses measurements and Kalman-filter estimates as inputs to predict unmeasured propulsion parameters such as net propulsive force and fan stall margin. The ability to track trends and estimate absolute values of propulsion system parameters was demonstrated. For example, thrust stand results show a good correlation especially in trends between the performance seeking control estimated and measured thrust.

  12. Experimental Methodology for Determining Optimum Process Parameters for Production of Hydrous Metal Oxides by Internal Gelation

    SciTech Connect

    Collins, J.L.

    2005-10-28

    The objective of this report is to describe a simple but very useful experimental methodology that was used to determine optimum process parameters for preparing several hydrous metal-oxide gel spheres by the internal gelation process. The method is inexpensive and very effective in collection of key gel-forming data that are needed to prepare the hydrous metal-oxide microspheres of the best quality for a number of elements.

  13. Research on the measuring technology of minute part's geometrical parameter based on image processing

    NASA Astrophysics Data System (ADS)

    Jia, Xiao-yan; Xiao, Ze-xin

    2008-03-01

    The measuring technology of minute part's geometrical parameter based on image processing is an integration of optics, the mechanics, electronics, calculation and control. Accomplishing the video alteration of measuring microscope, real-time gathering image with CCD, and compiling automatically measuring software in Visual C++6.0 environment. First to do image processing which includes denoise filter, illuminance non-uniformity adjustment and image enhancement, then to carry on the on-line automatic measuring to its geometry parameters. By measuring the minute part's geometry parameters of machineries and integrated circuit in this system, the experimental results indicate that the measuring accuracy could amount to 1 micron, and the system survey stability and usability are all good.

  14. Multiobjective optimization in structural design with uncertain parameters and stochastic processes

    NASA Technical Reports Server (NTRS)

    Rao, S. S.

    1984-01-01

    The application of multiobjective optimization techniques to structural design problems involving uncertain parameters and random processes is studied. The design of a cantilever beam with a tip mass subjected to a stochastic base excitation is considered for illustration. Several of the problem parameters are assumed to be random variables and the structural mass, fatigue damage, and negative of natural frequency of vibration are considered for minimization. The solution of this three-criteria design problem is found by using global criterion, utility function, game theory, goal programming, goal attainment, bounded objective function, and lexicographic methods. It is observed that the game theory approach is superior in finding a better optimum solution, assuming the proper balance of the various objective functions. The procedures used in the present investigation are expected to be useful in the design of general dynamic systems involving uncertain parameters, stochastic process, and multiple objectives.

  15. An IRT Model with a Parameter-Driven Process for Change

    ERIC Educational Resources Information Center

    Rijmen, Frank; De Boeck, Paul; van der Maas, Han L. J.

    2005-01-01

    An IRT model with a parameter-driven process for change is proposed. Quantitative differences between persons are taken into account by a continuous latent variable, as in common IRT models. In addition, qualitative inter-individual differences and auto-dependencies are accounted for by assuming within-subject variability with respect to the…

  16. Effect of processing parameters on surface finish for fused deposition machinable wax patterns

    NASA Technical Reports Server (NTRS)

    Roberts, F. E., III

    1995-01-01

    This report presents a study on the effect of material processing parameters used in layer-by-layer material construction on the surface finish of a model to be used as an investment casting pattern. The data presented relate specifically to fused deposition modeling using a machinable wax.

  17. An Approach to Optimize Size Parameters of Forging by Combining Hot-Processing Map and FEM

    NASA Astrophysics Data System (ADS)

    Hu, H. E.; Wang, X. Y.; Deng, L.

    2014-11-01

    The size parameters of 6061 aluminum alloy rib-web forging were optimized by using hot-processing map and finite element method (FEM) based on high-temperature compression data. The results show that the stress level of the alloy can be represented by a Zener-Holloman parameter in a hyperbolic sine-type equation with the hot deformation activation energy of 343.7 kJ/mol. Dynamic recovery and dynamic recrystallization concurrently preceded during high-temperature deformation of the alloy. Optimal hot-processing parameters for the alloy corresponding to the peak value of 0.42 are 753 K and 0.001 s-1. The instability domain occurs at deformation temperature lower than 653 K. FEM is an available method to validate hot-processing map in actual manufacture by analyzing the effect of corner radius, rib width, and web thickness on workability of rib-web forging of the alloy. Size parameters of die forgings can be optimized conveniently by combining hot-processing map and FEM.

  18. Calculating development parameters for chemically amplified resists by the film-reducing method

    NASA Astrophysics Data System (ADS)

    Sekiguchi, Atsushi; Sensu, Yoshihisa

    2013-03-01

    We obtained development parameters for a chemically amplified resist from calculations involving the conversion of the relationship between exposure dose and development rate to the relationship between protection ratio and development rate using the conventional ABC parameter[1] and development rate data (RDA data) [2]. However, calculations by this method require the ABC parameter. Since chemically amplified resists have no bleaching effect, the C parameter must be measured by the FT-IR [3-5] or coumarin addition method [6-8]. Given this constraint, we examined the method of obtaining development parameters based on the film reduction observed in the resist exposed or the film reduction observed after PEB, without using the ABC parameter. This paper presents the results.

  19. Analysis of the non-Markov parameter in continuous-time signal processing

    NASA Astrophysics Data System (ADS)

    Varghese, J. J.; Bellette, P. A.; Weegink, K. J.; Bradley, A. P.; Meehan, P. A.

    2014-02-01

    The use of statistical complexity metrics has yielded a number of successful methodologies to differentiate and identify signals from complex systems where the underlying dynamics cannot be calculated. The Mori-Zwanzig framework from statistical mechanics forms the basis for the generalized non-Markov parameter (NMP). The NMP has been used to successfully analyze signals in a diverse set of complex systems. In this paper we show that the Mori-Zwanzig framework masks an elegantly simple closed form of the first NMP, which, for C1 smooth autocorrelation functions, is solely a function of the second moment (spread) and amplitude envelope of the measured power spectrum. We then show that the higher-order NMPs can be constructed in closed form in a modular fashion from the lower-order NMPs. These results provide an alternative, signal processing-based perspective to analyze the NMP, which does not require an understanding of the Mori-Zwanzig generating equations. We analyze the parametric sensitivity of the zero-frequency value of the first NMP, which has been used as a metric to discriminate between states in complex systems. Specifically, we develop closed-form expressions for three instructive systems: band-limited white noise, the output of white noise input to an idealized all-pole filter,f and a simple harmonic oscillator driven by white noise. Analysis of these systems shows a primary sensitivity to the decay rate of the tail of the power spectrum.

  20. Effects of process parameters on the properties of biocompatible ibuprofen-loaded microcapsules.

    PubMed

    Valot, P; Baba, M; Nedelec, J-M; Sintes-Zydowicz, N

    2009-03-18

    The objective of this study was to obtain an optimum formulation for microencapsulating Ibuprofen. This was achieved by investigating various factors which influenced the microcapsule size. Considering Ibuprofen as a lipophilic model drug, biocompatible Ibuprofen-loaded microcapsules in the size range of 20-60microm were prepared by the water in oil emulsion-solvent evaporation method. An aqueous surfactant phase was used as the continuous external phase (W), a biocompatible organic solvent dissolving Ibuprofen was used as oil phase (O), in addition with a low boiling solvent. The biocompatible polymeric microcapsule membrane was composed of Eudragit RSPO or Ethylcellulose. The influence of various process parameters, such as the volatile organic solvent, the oily core, the stirring rate, on the characteristics of microcapsules was investigated. The encapsulation yield of Ibuprofen close to 100%, whatever the polymer type, was determined by UV-vis experiments, in accordance with the results obtained by (13)C NMR spectroscopy. An innovative technique, DSC-based thermoporosimetry, was used for the estimation of the loading rate of Ibuprofen. The results indicated that this developed analytical method had to be improved since DSC-transitions accounted to free and enclosed Ibuprofen were observed and altered the accuracy of the results. PMID:19084583

  1. Recommended direct simulation Monte Carlo collision model parameters for modeling ionized air transport processes

    NASA Astrophysics Data System (ADS)

    Swaminathan-Gopalan, Krishnan; Stephani, Kelly A.

    2016-02-01

    A systematic approach for calibrating the direct simulation Monte Carlo (DSMC) collision model parameters to achieve consistency in the transport processes is presented. The DSMC collision cross section model parameters are calibrated for high temperature atmospheric conditions by matching the collision integrals from DSMC against ab initio based collision integrals that are currently employed in the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA) and Data Parallel Line Relaxation (DPLR) high temperature computational fluid dynamics solvers. The DSMC parameter values are computed for the widely used Variable Hard Sphere (VHS) and the Variable Soft Sphere (VSS) models using the collision-specific pairing approach. The recommended best-fit VHS/VSS parameter values are provided over a temperature range of 1000-20 000 K for a thirteen-species ionized air mixture. Use of the VSS model is necessary to achieve consistency in transport processes of ionized gases. The agreement of the VSS model transport properties with the transport properties as determined by the ab initio collision integral fits was found to be within 6% in the entire temperature range, regardless of the composition of the mixture. The recommended model parameter values can be readily applied to any gas mixture involving binary collisional interactions between the chemical species presented for the specified temperature range.

  2. Optimization of process parameters for production of volatile fatty acid, biohydrogen and methane from anaerobic digestion.

    PubMed

    Khan, M A; Ngo, H H; Guo, W S; Liu, Y; Nghiem, L D; Hai, F I; Deng, L J; Wang, J; Wu, Y

    2016-11-01

    The anaerobic digestion process has been primarily utilized for methane containing biogas production over the past few years. However, the digestion process could also be optimized for producing volatile fatty acids (VFAs) and biohydrogen. This is the first review article that combines the optimization approaches for all three possible products from the anaerobic digestion. In this review study, the types and configurations of the bioreactor are discussed for each type of product. This is followed by a review on optimization of common process parameters (e.g. temperature, pH, retention time and organic loading rate) separately for the production of VFA, biohydrogen and methane. This review also includes additional parameters, treatment methods or special additives that wield a significant and positive effect on production rate and these products' yield. PMID:27570139

  3. Phases' characteristics of poultry litter hydrothermal carbonization under a range of process parameters.

    PubMed

    Mau, Vivian; Quance, Julie; Posmanik, Roy; Gross, Amit

    2016-11-01

    The aim of this work was to study the hydrothermal carbonization of poultry litter under a range of process parameters. Experiments were conducted to investigate the effect of HTC of poultry litter under a range of operational parameters (temperature, reaction time, and solids concentration) on the formation and characteristics of its phases. Results showed production of a hydrochar with caloric value of 24.4MJ/kg, similar to sub-bituminous coal. The gaseous phase consisted mainly of CO2. However, significant amounts of H2S dictate the need for (further) treatment. The process also produced an aqueous phase with chemical characteristics suggesting its possible use as a liquid fertilizer. Temperature had the most significant effect on processes and product formation. Solids concentration was not a significant factor once dilution effects were considered. PMID:27544913

  4. Analysis and optimization of process parameters in Al-SiCp laser cladding

    NASA Astrophysics Data System (ADS)

    Riquelme, Ainhoa; Rodrigo, Pilar; Escalera-Rodríguez, María Dolores; Rams, Joaquín

    2016-03-01

    The laser cladding process parameters have great effect on the clad geometry and on dilution in the single and multi-pass aluminum matrix composite reinforced with SiC particles (Al/SiCp) coatings on ZE41 magnesium alloys deposited using a high-power diode laser (HPLD). The influence of the laser power (500-700 W), scan speed (3-17 mm/s) and laser beam focal position (focus, positive and negative defocus) on the shape factor, cladding-bead geometry, cladding-bead microstructure (including the presence of pores and cracks), and hardness has been evaluated. The correlation of these process parameters and their influence on the properties and ultimately, on the feasibility of the cladding process, is demonstrated. The importance of focal position is demonstrated. The different energy distribution of the laser beam cross section in focus plane or in positive and negative defocus plane affect on the cladding-bead properties.

  5. The Effect of Process Parameters on the Microstructure and Mechanical Properties of Semisolid Cast Al6061

    NASA Astrophysics Data System (ADS)

    Hajihashemi, Mahdi; Niroumand, Behzad; Shamanian, Morteza

    2015-04-01

    An examination of the microstructure and mechanical properties of aluminum 6061 alloy samples produced by a miniature cooling slope is presented. The effects of several process parameters including pouring rate, cooling slope angle, superheat and cooling slope length on the microstructure and mechanical characteristics of the samples were investigated. An attempt was made to use the two-level factorial design method to determine the relationships between the process parameters and the properties of the semisolid aluminum 6061 alloy manufactured by the miniature cooling slope. Finally, an optimum processing region was identified. The interaction between the cooling slope length and the pouring rate ( BC); the interaction among the superheat, the pouring rate, and the cooling slope length ( ABC); and the cooling slope length (C), in the order mentioned, were identified as the most important effects.

  6. Development of modified FT (MFT) process

    SciTech Connect

    Jinglai Zhou; Zhixin Zhang; Wenjie Shen

    1995-12-31

    Two-Stage Modified FT (MFT) process has been developed for producing high-octane gasoline from coal-based syngas. The main R&D are focused on the development of catalysts and technologies process. Duration tests were finished in the single-tube reactor, pilot plant (100T/Y), and industrial demonstration plant (2000T/Y). A series of satisfactory results has been obtained in terms of operating reliability of equipments, performance of catalysts, purification of coal - based syngas, optimum operating conditions, properties of gasoline and economics etc. Further scaling - up commercial plant is being considered.

  7. Apoptotic processes during mammalian preimplantation development.

    PubMed

    Fabian, Dusan; Koppel, Juraj; Maddox-Hyttel, Poul

    2005-07-15

    The paper provides a review of the current state of knowledge on apoptosis during normal preimplantation development based on the literature and on the authors' own findings. Information is focused on the occurrence and the characteristics of spontaneous apoptotic processes. Reports concerning the chronology and the incidence of programmed cell death in mouse, cow, pig and human embryos in early preimplantation stages up to the blastocyst stage are summarized. In addition, specific attributes of the apoptotic process in mammalian preimplantation development are provided, including the description of both morphological and biochemical features of cell death. PMID:15955348

  8. Development of superplastic steel processing. Final report

    SciTech Connect

    Goldberg, A.

    1995-04-01

    Objective was to provide basis for producing, processing, and forming UHCS (ultrahigh carbon steel) on a commercial scale. Business plans were developed for potential commercialization. Effort was directed at improving the combination of flow stress and forming rates in UHCS alloys in order to make near net shape superplastic forming competitive; the result was the development of a series of UHCS alloys and processing, the selection of which depends on the specific requirements of the commercial application. Useful ancillary properties of these materials include: improved mechanical properties, wear resistance, and oxidation resistance at elevated temperatures.

  9. Development of emission factors for polycarbonate processing.

    PubMed

    Rhodes, Verne L; Kriek, George; Lazear, Nelson; Kasakevich, Jean; Martinko, Marie; Heggs, R P; Holdren, M W; Wisbith, A S; Keigley, G W; Williams, J D; Chuang, J C; Satola, J R

    2002-07-01

    Emission factors for selected volatile organic compounds (VOCs) and particulate emissions were developed while processing eight commercial grades of polycarbonate (PC) and one grade of a PC/acrylonitrile-butadiene-styrene (ABS) blend. A small commercial-type extruder was used, and the extrusion temperature was held constant at 304 degrees C. An emission factor was calculated for each substance measured and is reported as pounds released to the atmosphere/million pounds of polymer resin processed [ppm (wt/wt)]. Scaled to production volumes, these emission factors can be used by processors to estimate emission quantities from similar PC processing operations. PMID:12139342

  10. Femtosecond laser ablation properties of transparent materials: impact of the laser process parameters on the machining throughput

    NASA Astrophysics Data System (ADS)

    Matylitsky, V. V.; Hendricks, F.; Aus der Au, J.

    2013-03-01

    High average power, high repetition rate femtosecond lasers with μJ pulse energies are increasingly used for bio-medical and material processing applications. With the introduction of femtosecond laser systems such as the SpiritTM platform developed by High Q Lasers and Spectra-Physics, micro-processing of solid targets with femtosecond laser pulses have obtained new perspectives for industrial applications [1]. The unique advantage of material processing with subpicosecond lasers is efficient, fast and localized energy deposition, which leads to high ablation efficiency and accuracy in nearly all kinds of solid materials. The study on the impact of the laser processing parameters on the removal rate for transparent substrate using femtosecond laser pulses will be presented. In particular, examples of micro-processing of poly-L-lactic acid (PLLA) - bio-degradable polyester and XensationTM glass (Schott) machined with SpiritTM ultrafast laser will be shown.

  11. Surface treatment with small laser spots: an approach for the comparison of process parameters

    NASA Astrophysics Data System (ADS)

    Kreling, Stefan; Grefe, Hinrich; Dilger, Klaus

    2016-03-01

    Pulsed lasers with spot diameters in the μm range are widely used for the laminar treatment of surfaces. The laminar treatment is achieved by a two-dimensional overlap of the small laser pulses going from lines to a surface. This publication states the numerical description of the average amount of laser pulses per surface increment and its spread considering processing parameters such as line feed, pulse repetition rate and hatch distance. Based on the numerical results an empirical formula was derived and the basic approach of calculating an accumulated energy as a benchmark for comparing pre-treatment parameters was investigated for different laser systems.

  12. Hydrothermal carbonization of biomass from landscape management - Influence of process parameters on soil properties of hydrochars.

    PubMed

    Röhrdanz, Michael; Rebling, Tammo; Ohlert, Jan; Jasper, Jan; Greve, Thomas; Buchwald, Rainer; von Frieling, Petra; Wark, Michael

    2016-05-15

    Besides pyrolysis the technology of hydrothermal carbonization (HTC) is tested to produce hydrochars for soil improvement. The chemical and physical properties of the hydrochars mainly depend on the feedstock and the process parameters reaction time and process temperature. Systematic investigations on the influences of these process parameters on soil properties of hydrochars like water holding capacity (WHC) and cation exchange capacity (CEC) are missing. In this study, a rush-rich biomass was carbonized within defined HTC process conditions under variation of reaction time and process temperature to produce hydrochars. Analysis of WHC, CEC, the elemental composition and Fourier-transform infrared spectroscopy (FT-IR) were performed to evaluate the influence of HTC process conditions on the pedological hydrochar properties. The results indicated that at increasing reaction severity (reaction time and process temperature) WHC and CEC decreased as well as the elemental O/C ratio. The decrease of WHC and CEC is based on the decrease of the hydrochar surface polarity. However, even the lowest WHC and CEC of investigated hydrochars still exceeded those of pure quartz sand by factors of 5-10. An application of hydrochars produced at severe HTC conditions could improve WHC and CEC of sandy soils. This has to be investigated in further studies. PMID:26974240

  13. Simulation, part path correction, and automated process parameter selection for ultrashort pulsed laser micromachining of sapphire

    NASA Astrophysics Data System (ADS)

    Blood, Daniel A.

    This dissertation describes an ultrashort pulsed laser material removal simulator with X-Y stage acceleration profile consideration and part path compensation. Ultrashort pulsed lasers offer the advantage of single step processing of various materials with high repeatability. Over the past 30 years the laser repetition rate and power output have increased, and although this increases the material removal rate, it also introduces new challenges. The acceleration rates of the X-Y stages on a laser micromachining setup are finite, but this has been neglected. In the past the acceleration rate has been negligible due to low repetition rates; however, for high repetition rates the acceleration and deceleration regions introduce local variations in the material removal. A novel method is presented that accounts for the stage dynamics to produce a more robust simulated cut. In addition to the simulator, a technique for modifying the part path to reduce non-uniformity in the material removal is discussed. The laser operator has access to a variety of process parameters that ultimately affect the cost and quality of the machined component. Choosing the correct combination of these parameters requires knowledge of the machining process, and the wrong combination can result in a feature that is unsatisfactory and/or overly expensive. The modification of these parameters, and a correction of the part path allows for a more uniform depth of cut and higher feature quality. This dissertation contains three main contributions. The first contribution is to quantify the relationship between ultrashort pulsed laser machining parameters and the ablation depth of sapphire. The second is to produce a pulsed laser micromachining simulator that includes not only the laser-material interaction, but also the nuances of controlling the position of the laser beam on the workpiece. The final contribution is to produce a part path correction program with an automated process parameter routine

  14. Effects of Forging Process Parameters on Microstructure Evolution of Aluminum Alloy 7050

    SciTech Connect

    Yi Youping; Shi Yan; Yang Jihui; Lin Yongcheng

    2007-04-07

    The objective of this work is to investigate the behavior of microstructure evolution of aluminum alloy 7050 under the condition of different forging process parameters by means of combining materials physical model with finite element code. For the purpose of establishing constitutive equation and physical model of microstructure evolution, the isothermal compression test were performed by machine Gleeble 1500 on the condition of temperatures ranging from 250 deg. C to 450 deg. C and constant strain rates of 0.01s-1, 0.1s-1, 1s-1 and 10s-1. The behaviors of microstructure evolutions of aluminum alloy 7050 under difference process parameters were studied by metallographic observations. The experiment results showed that recrystallization during forming process occurred at the critical strain and the volume fraction of recrystallization changed with the temperature and strain rate. According to the results of isothermal compression test, a constitutive equation and an empirical model of DRX were obtained. A finite element code DEFORM 3D was used to analyze the influence of different forging process parameters on the behavior of microstructure evolution in details. The present model and simulation method can be served as a useful tool to predict and control the properties and shape of aluminum alloy 7050 components during forging.

  15. Lexical Morphology: Structure, Process, and Development

    ERIC Educational Resources Information Center

    Jarmulowicz, Linda; Taran, Valentina L.

    2013-01-01

    Recent work has demonstrated the importance of derivational morphology to later language development and has led to a consensus that derivation is a lexical process. In this review, derivational morphology is discussed in terms of lexical representation models from both linguistic and psycholinguistic perspectives. Input characteristics, including…

  16. Development of a New Simultaneous Processing Scale.

    ERIC Educational Resources Information Center

    Keefe, James W.; Languis, Marlin L.

    The Learning Style Profile (LSP), developed in four phases from the fall of 1983 to early 1986, identifies perceptual responses, cognitive skills, study preferences, and instructional preferences. This study assesses the LSP Simultaneous Processing Skill subscale, which is modeled after the work of the Russian neuropsychologist, A. R. Luria.…

  17. L2 Chinese: Grammatical Development and Processing

    ERIC Educational Resources Information Center

    Mai, Ziyin

    2016-01-01

    Two recent books (Jiang, 2014, "Advances in Chinese as a second language"; Wang, 2013, "Grammatical development of Chinese among non-native speakers") provide new resources for exploring the role of processing in acquiring Chinese as a second language (L2). This review article summarizes, assesses and compares some of the…

  18. Developing Qualitative Research Questions: A Reflective Process

    ERIC Educational Resources Information Center

    Agee, Jane

    2009-01-01

    The reflective and interrogative processes required for developing effective qualitative research questions can give shape and direction to a study in ways that are often underestimated. Good research questions do not necessarily produce good research, but poorly conceived or constructed questions will likely create problems that affect all…

  19. Reduced iron parameters and cognitive processes in children and adolescents with DM1 compared to those with standard parameters.

    PubMed

    Mojs, Ewa; Stanisławska-Kubiak, Maia; Wójciak, Rafał W; Wojciechowska, Julita; Przewoźniak, Sabina

    2016-03-01

    Anemia in patients with diabetes is not scarce and may contribute to the complications of the disease. The risk of iron deficiency parameters in child sufferers of diabetes type 1, observed in studies, can lead to cognitive impairment. The aim of the study was to determine whether children and adolescents with diabetes type 1, in whom reduced ferric parameters are observed in control tests, may also show reduced cognitive performance. The study included 100 children with diabetes type 1 at the age of 6-17 years. During control tests, patients' morphological blood parameters were measured: red blood cells (RBC), hemoglobin, glycosylated hemoglobin, hematocrit, RBC volume, the molar mass of hemoglobin in RBC (MCH), mean corpuscular hemoglobin in RBC and iron concentrations in serum using flame atomic absorption spectroscopy and the Wechsler Intelligence Scale for Children (WISC-R). Results in the group of children with a diabetes type 1 significantly lower concentration of three ferric parameters affect the non-verbal intelligence measured with WISC-R. The prevalence of reduced ferric parameters justifies further screening in all children with diabetes type 1 and taking up appropriate preventive measures to reduce the risk of their occurrence. PMID:26912011

  20. Process modeling and parameter optimization using radial basis function neural network and genetic algorithm for laser welding of dissimilar materials

    NASA Astrophysics Data System (ADS)

    Ai, Yuewei; Shao, Xinyu; Jiang, Ping; Li, Peigen; Liu, Yang; Yue, Chen

    2015-11-01

    The welded joints of dissimilar materials have been widely used in automotive, ship and space industries. The joint quality is often evaluated by weld seam geometry, microstructures and mechanical properties. To obtain the desired weld seam geometry and improve the quality of welded joints, this paper proposes a process modeling and parameter optimization method to obtain the weld seam with minimum width and desired depth of penetration for laser butt welding of dissimilar materials. During the process, Taguchi experiments are conducted on the laser welding of the low carbon steel (Q235) and stainless steel (SUS301L-HT). The experimental results are used to develop the radial basis function neural network model, and the process parameters are optimized by genetic algorithm. The proposed method is validated by a confirmation experiment. Simultaneously, the microstructures and mechanical properties of the weld seam generated from optimal process parameters are further studied by optical microscopy and tensile strength test. Compared with the unoptimized weld seam, the welding defects are eliminated in the optimized weld seam and the mechanical properties are improved. The results show that the proposed method is effective and reliable for improving the quality of welded joints in practical production.

  1. Process development for scum to biodiesel conversion.

    PubMed

    Bi, Chong-hao; Min, Min; Nie, Yong; Xie, Qing-long; Lu, Qian; Deng, Xiang-yuan; Anderson, Erik; Li, Dong; Chen, Paul; Ruan, Roger

    2015-06-01

    A novel process was developed for converting scum, a waste material from wastewater treatment facilities, to biodiesel. Scum is an oily waste that was skimmed from the surface of primary and secondary settling tanks in wastewater treatment plants. Currently scum is treated either by anaerobic digestion or landfilling which raised several environmental issues. The newly developed process used a six-step method to convert scum to biodiesel, a higher value product. A combination of acid washing and acid catalyzed esterification was developed to remove soap and impurities while converting free fatty acids to methyl esters. A glycerol washing was used to facilitate the separation of biodiesel and glycerin after base catalyzed transesterification. As a result, 70% of dried and filtered scum was converted to biodiesel which is equivalent to about 134,000 gallon biodiesel per year for the Saint Paul waste water treatment plant in Minnesota. PMID:25770465

  2. Development of enhanced sulfur rejection processes

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.; Adel, G.T.; Richardson, P.E.

    1996-03-01

    Research at Virginia Tech led to the development of two complementary concepts for improving the removal of inorganic sulfur from many eastern U.S. coals. These concepts are referred to as Electrochemically Enhanced Sulfur Rejection (EESR) and Polymer Enhanced Sulfur Rejection (PESR) processes. The EESR process uses electrochemical techniques to suppress the formation of hydrophobic oxidation products believed to be responsible for the floatability of coal pyrite. The PESR process uses polymeric reagents that react with pyrite and convert floatable middlings, i.e., composite particles composed of pyrite with coal inclusions, into hydrophilic particles. These new pyritic-sulfur rejection processes do not require significant modifications to existing coal preparation facilities, thereby enhancing their adoptability by the coal industry. It is believed that these processes can be used simultaneously to maximize the rejection of both well-liberated pyrite and composite coal-pyrite particles. The project was initiated on October 1, 1992 and all technical work has been completed. This report is based on the research carried out under Tasks 2-7 described in the project proposal. These tasks include Characterization, Electrochemical Studies, In Situ Monitoring of Reagent Adsorption on Pyrite, Bench Scale Testing of the EESR Process, Bench Scale Testing of the PESR Process, and Modeling and Simulation.

  3. Post-processing of seismic parameter data based on valid seismic event determination

    DOEpatents

    McEvilly, Thomas V.

    1985-01-01

    An automated seismic processing system and method are disclosed, including an array of CMOS microprocessors for unattended battery-powered processing of a multi-station network. According to a characterizing feature of the invention, each channel of the network is independently operable to automatically detect, measure times and amplitudes, and compute and fit Fast Fourier transforms (FFT's) for both P- and S- waves on analog seismic data after it has been sampled at a given rate. The measured parameter data from each channel are then reviewed for event validity by a central controlling microprocessor and if determined by preset criteria to constitute a valid event, the parameter data are passed to an analysis computer for calculation of hypocenter location, running b-values, source parameters, event count, P- wave polarities, moment-tensor inversion, and Vp/Vs ratios. The in-field real-time analysis of data maximizes the efficiency of microearthquake surveys allowing flexibility in experimental procedures, with a minimum of traditional labor-intensive postprocessing. A unique consequence of the system is that none of the original data (i.e., the sensor analog output signals) are necessarily saved after computation, but rather, the numerical parameters generated by the automatic analysis are the sole output of the automated seismic processor.

  4. The Effects of Operational Parameters on a Mono-wire Cutting System: Efficiency in Marble Processing

    NASA Astrophysics Data System (ADS)

    Yilmazkaya, Emre; Ozcelik, Yilmaz

    2016-02-01

    Mono-wire block cutting machines that cut with a diamond wire can be used for squaring natural stone blocks and the slab-cutting process. The efficient use of these machines reduces operating costs by ensuring less diamond wire wear and longer wire life at high speeds. The high investment costs of these machines will lead to their efficient use and reduce production costs by increasing plant efficiency. Therefore, there is a need to investigate the cutting performance parameters of mono-wire cutting machines in terms of rock properties and operating parameters. This study aims to investigate the effects of the wire rotational speed (peripheral speed) and wire descending speed (cutting speed), which are the operating parameters of a mono-wire cutting machine, on unit wear and unit energy, which are the performance parameters in mono-wire cutting. By using the obtained results, cuttability charts for each natural stone were created on the basis of unit wear and unit energy values, cutting optimizations were performed, and the relationships between some physical and mechanical properties of rocks and the optimum cutting parameters obtained as a result of the optimization were investigated.

  5. A more informative estimation procedure for the parameters of a diffusion process

    NASA Astrophysics Data System (ADS)

    Basso, A.; Pianca, P.

    1999-07-01

    The estimation procedures for the parameters of a diffusion process with constant coefficients have mainly focused on volatility. Nevertheless, even if the knowledge of the volatility alone suffices to compute the Black and Scholes option prices, other financial application models assume that the price dynamics follows a log-normal process and requires the knowledge of both parameters. On the other hand, while the usual ML estimator of volatility gives satisfactory results, the estimation of drift is much less accurate; moreover, the drift-estimated value highly depends on the phases of the business cycle included in the sample data. This contribution explicitly imposes a risk aversion or risk neutral assumption into the ML estimation procedure and makes a constrained maximization of the sample likelihood function. The aim is twofold: to obtain estimated values which are consistent with a widely accepted assumption and use the risk aversion constraint in order to improve the accuracy of the estimates.

  6. Effects of process parameters on microstructural evolution and properties of AZ61 alloy during hot extrusion

    NASA Astrophysics Data System (ADS)

    Lu, Y. L.; Li, X. C.; Xu, W. T.; Wu, D.; Yang, M.

    2015-12-01

    Extrusion testing of AZ61 alloys were conducted at deformation temperatures of 300°C to 410°C and extrusion ratios of 3, 10 and 16 respectively to optimize the process parameters. The experimental results show that deformation process parameters significantly affect microstructures and properties. Optical microscope observation shows that grains are refined greatly during hot extrusion and the mechanical properties are improved with increasing the extrusion ratio. For AZ61 alloy, the optimal extrusion temperature is 370 °C. When deformation temperature increases, more slip systems participate in the plastic deformation, which leads to the decrease of the cleavage surface. After severe plastic deformation, a remarkable improvement of ductility of AZ61 alloy has been found. The ductile fracture mechanism is gradually dominant instead of brittle fracture with increasing the extrusion ratio.

  7. Influence of process parameters on pellets elaborated in a Mi-pro high-shear granulator.

    PubMed

    Chevalier, E; Viana, M; Pouget, C; Chulia, D

    2007-01-01

    The aim of the study was to prepare porous pellets several hundred micrometers in diameter into or onto which drug substances could be embedded. Wet granulation was carried out on a powder mix of alpha-lactose and polyvinylpyrrolidone in a Mi-Pro high-shear granulator. The process parameters were investigated to point out their influence on pellet physical properties. The reference conditions of granulation that gave the most satisfactory pellets in size and shape were determined by adjusting the volume and the distribution rate of water. Increasing impeller speed resulted in an increase in granule size and granulation yield and in a decrease in proportion of fines. The granules showed easy flowing for all granulation conditions. Adjusting process parameters enabled control of size, shape, surface area, and porosity of the granules and thus the design of ready to use granules to which drug substances could be associated by deposition or inclusion. PMID:17510884

  8. Reduced O2 concentration during CAM development--its effect on physiological parameters of broiler embryos.

    PubMed

    Druyan, S; Levi, E; Shinder, D; Stern, T

    2012-04-01

    Embryo development is a dynamic process, determined by both the genetic background of the organism and the environment in which it develops. Environmental alterations during an organism's embryogenesis may induce changes in the development of some physiological regulatory systems, thereby causing permanent phenotypic changes in the embryo. The present study aimed to assess the effect of 17% O(2) concentration during chorioallantoic membrane (CAM) development on a) CAM development, b) cardiovascular parameters, and c) embryo development postexposure and up to hatch. Two replicated trials, each with 840 fertile Cobb eggs, were conducted. At embryonic d 5 (E5) eggs were divided into 2 treatments: 1) control, and 2) 17% O(2) concentration for 12 h/d from E5 through E12 (12H). The 12H embryos exhibited a clear and significant increase in the vascular area of the CAM, which grew to 6.8% larger than that of the control. Hematocrit and hemoglobin levels, as measured on E13 and E14, increased in response to the hypoxic treatments, but these differences were not maintained subsequently. Heart rate and relative heart weight were not affected by hypoxic exposure, but eggshell temperature in the 12H treatment was higher than that of the control, indicating higher heat production, which is consistent with the elevated plasma concentrations of triiodothyronine and thyroxin and with the enhanced oxygen consumption and residual yolk intake rate that followed exposure to hypoxic conditions. These findings indicate that embryos adapted to hypoxic condition enhance angiogenesis processes, which subsequently increase their blood oxygen-carrying capacity, enabling the increase of oxygen consumption, which positively affects their growth development and maturation compared with the control embryos. Such alterations may affect posthatch performance and the ability of broilers cardiovascular system to meet elevated oxygen demand. PMID:22399739

  9. The Development and Application of an Integrated VAR Process Model

    NASA Astrophysics Data System (ADS)

    Ballantyne, A. Stewart

    2016-07-01

    The VAR ingot has been the focus of several modelling efforts over the years with the result that the thermal regime in the ingot can be simulated quite realistically. Such models provide important insight into solidification of the ingot but present some significant challenges to the casual user such as a process engineer. To provide the process engineer with a tool to assist in the development of a melt practice, a comprehensive model of the complete VAR process has been developed. A radiation heat transfer simulation of the arc has been combined with electrode and ingot models to develop a platform which accepts typical operating variables (voltage, current, and gap) together with process parameters (electrode size, crucible size, orientation, water flow, etc.) as input data. The output consists of heat flow distributions and solidification parameters in the form of text, comma-separated value, and visual toolkit files. The resulting model has been used to examine the relationship between the assumed energy distribution in the arc and the actual energy flux which arrives at the ingot top surface. Utilizing heat balance information generated by the model, the effects of electrode-crucible orientation and arc gap have been explored with regard to the formation of ingot segregation defects.

  10. Continuous melt granulation: Influence of process and formulation parameters upon granule and tablet properties.

    PubMed

    Monteyne, Tinne; Vancoillie, Jochem; Remon, Jean-Paul; Vervaet, Chris; De Beer, Thomas

    2016-10-01

    The pharmaceutical industry has a growing interest in alternative manufacturing models allowing automation and continuous production in order to improve process efficiency and reduce costs. Implementing a switch from batch to continuous processing requires fundamental process understanding and the implementation of quality-by-design (QbD) principles. The aim of this study was to examine the relationship between formulation-parameters (type binder, binder concentration, drug-binder miscibility), process-parameters (screw speed, powder feed rate and granulation temperature), granule properties (size, size distribution, shape, friability, true density, flowability) and tablet properties (tensile strength, friability, dissolution rate) of four different drug-binder formulations using Design of experiments (DOE). Two binders (polyethylene glycol (PEG) and Soluplus®) with a different solid state, semi-crystalline vs amorphous respectively, were combined with two model-drugs, metoprolol tartrate (MPT) and caffeine anhydrous (CAF), both having a contrasting miscibility with the binders. This research revealed that the granule properties of miscible drug-binder systems depended on the powder feed rate and barrel filling degree of the granulator whereas the granule properties of immiscible systems were mainly influenced by binder concentration. Using an amorphous binder, the tablet tensile strength depended on the granule size. In contrast, granule friability was more important for tablet quality using a brittle binder. However, this was not the case for caffeine-containing blends, since these phenomena were dominated by the enhanced compression properties of caffeine Form I, which was formed during granulation. Hence, it is important to gain knowledge about formulation behavior during processing since this influences the effect of process parameters onto the granule and tablet properties. PMID:27449628

  11. Influence of processing parameters on long lasting hybrid phosphor for LED applications

    NASA Astrophysics Data System (ADS)

    Jain, Abhilasha; Kumar, Ashwini; Dhoble, S. J.; Peshwe, D. R.

    2016-05-01

    Rare earth activated hybrid phosphors have made significant progress in terms of better light output, color properties and potential for long life. All these features coupled with low cost production and reduced maintenance have offered phosphor converted LEDs for diverse optoelectronic applications including signal lighting in advanced aviation. The present paper explores the effect of various processing parameters on luminescent hybrid phosphors fabricated through combustion synthesis.

  12. Ergodicity and Parameter Estimates for Infinite-Dimensional Fractional Ornstein-Uhlenbeck Process

    SciTech Connect

    Maslowski, Bohdan Pospisil, Jan

    2008-06-15

    Existence and ergodicity of a strictly stationary solution for linear stochastic evolution equations driven by cylindrical fractional Brownian motion are proved. Ergodic behavior of non-stationary infinite-dimensional fractional Ornstein-Uhlenbeck processes is also studied. Based on these results, strong consistency of suitably defined families of parameter estimators is shown. The general results are applied to linear parabolic and hyperbolic equations perturbed by a fractional noise.

  13. New developments of process technologies for microfabrication

    NASA Astrophysics Data System (ADS)

    Piotter, Volker; Hanemann, Thomas; Ruprecht, Robert; Thies, Andreas; Hausselt, Juergen H.

    1997-09-01

    Economic success of microsystems technology requires cost- effective fabrication in large series as well as a great diversity of materials processing technologies. The different techniques of micro molding meet all these requirements. An important economic factor is the reduction of cycle time by process and tool optimization with simulation techniques. Actually, minimal cycle times are about two minutes in certain cases. Evolution of thermoplastics processing technologies is demonstrated by application of technical or even high- performance polymers like PEEK, PMMA or PSU. For manufacturing of metal microstructures, we develop three possibilities: microstructures like stepped LIGA gear wheels are obtained from galvanization on lost molds, which have been injection molded using conductively filled polymers. Additionally, electroless plating is used to replicate nonconducting plastic microstructures and the metal injection molding (MIM) process is under development. A quite different approach uses polymer precursors containing monomer/polymer mixtures in reaction injection molding. We chose photoinduced polymerization without any preheating step using photopolymerizable resins. Avoiding the time consuming thermal cycle, molding takes place at ambient temperature. Due to the low viscosity, the microcavities should be filled completely. The process is characterized by the integration of a powerful UV-source and a partially glass made molding tool.

  14. Process development of thin strip steel casting

    SciTech Connect

    Sussman, R.C.; Williams, R.S.

    1990-12-01

    An important new frontier is being opened in steel processing with the emergence of thin strip casting. Casting steel directly to thin strip has enormous benefits in energy savings by potentially eliminating the need for hot reduction in a hot strip mill. This has been the driving force for numerous current research efforts into the direct strip casting of steel. The US Department of Energy initiated a program to evaluate the development of thin strip casting in the steel industry. In earlier phases of this program, planar flow casting on an experimental caster was studied by a team of engineers from Westinghouse Electric corporation and Armco Inc. A subsequent research program was designed as a fundamental and developmental study of both planar and melt overflow casting processes. This study was arranged as several separate and distinct tasks which were often completed by different teams of researchers. An early task was to design and build a water model to study fluid flow through different designs of planar flow casting nozzles. Another important task was mathematically modeling of melt overflow casting process. A mathematical solidification model for the formation of the strip in the melt overflow process was written. A study of the material and conditioning of casting substrates was made on the small wheel caster using the melt overflow casting process. This report discusses work on the development of thin steel casting.

  15. Development of an Ontology-Directed Signal Processing Toolbox

    SciTech Connect

    Stephen W. Lang

    2011-05-27

    This project was focused on the development of tools for the automatic configuration of signal processing systems. The goal is to develop tools that will be useful in a variety of Government and commercial areas and useable by people who are not signal processing experts. In order to get the most benefit from signal processing techniques, deep technical expertise is often required in order to select appropriate algorithms, combine them into a processing chain, and tune algorithm parameters for best performance on a specific problem. Therefore a significant benefit would result from the assembly of a toolbox of processing algorithms that has been selected for their effectiveness in a group of related problem areas, along with the means to allow people who are not signal processing experts to reliably select, combine, and tune these algorithms to solve specific problems. Defining a vocabulary for problem domain experts that is sufficiently expressive to drive the configuration of signal processing functions will allow the expertise of signal processing experts to be captured in rules for automated configuration. In order to test the feasibility of this approach, we addressed a lightning classification problem, which was proposed by DOE as a surrogate for problems encountered in nuclear nonproliferation data processing. We coded a toolbox of low-level signal processing algorithms for extracting features of RF waveforms, and demonstrated a prototype tool for screening data. We showed examples of using the tool for expediting the generation of ground-truth metadata, for training a signal recognizer, and for searching for signals with particular characteristics. The public benefits of this approach, if successful, will accrue to Government and commercial activities that face the same general problem - the development of sensor systems for complex environments. It will enable problem domain experts (e.g. analysts) to construct signal and image processing chains without

  16. Thermal EOR process research and development

    SciTech Connect

    Engi, D.; Aeschliman, D.P.; Moreno, J.B.

    1985-01-01

    This paper describes recent results of Research and Development activities associated with thermal EOR processes in the areas of process mapping, downhole steam generator (DSG) materials performance, and insulated tubulars. Field measurements which can be used to map overall geometry and local stability of the displacement fronts would be particularly useful in the context of process control. Electromagnetic techniques which are being developed to make these measurements are currently limited to qualitative interpretations. This paper first describes lab scale physical simulations being conducted to develop a fundamental understanding of the variations in electrical properties associated with the constitutive zones of a recovery process to improve our ability to interpret field data. Field tests in 1981 to 1982 identified DSG combustor material failure as the primary technical concern in DSG development, with the presumption that the failure mode was due to mixed hot gas corrosion. Experimental results are summarized here for a variety of candidate combustor materials, chosen largely for corrosion resistance. No important differences in performance were found. More recently, analytical studies supported by a single experiment on a thin-walled combustor liner have suggested that thermally-induced stress in the thick-walled liners used is the probable cause of failure. Insulated steam injection tubulars have been observed to be less effective in reducing wellbore heat loss if operated in a wet wellbore - a typical situation. Wellbore refluxing, a process analogous to the action of a heat pipe, was proposed in 1983 to be the source of the reduced efficiency. The results of recently completed tests on insulated tubing in wet and dry wellbores are reported. 23 references, 16 figures, 3 tables.

  17. Development of a neuro-fuzzy technique for automated parameter optimization of inverse treatment planning

    PubMed Central

    Stieler, Florian; Yan, Hui; Lohr, Frank; Wenz, Frederik; Yin, Fang-Fang

    2009-01-01

    Background Parameter optimization in the process of inverse treatment planning for intensity modulated radiation therapy (IMRT) is mainly conducted by human planners in order to create a plan with the desired dose distribution. To automate this tedious process, an artificial intelligence (AI) guided system was developed and examined. Methods The AI system can automatically accomplish the optimization process based on prior knowledge operated by several fuzzy inference systems (FIS). Prior knowledge, which was collected from human planners during their routine trial-and-error process of inverse planning, has first to be "translated" to a set of "if-then rules" for driving the FISs. To minimize subjective error which could be costly during this knowledge acquisition process, it is necessary to find a quantitative method to automatically accomplish this task. A well-developed machine learning technique, based on an adaptive neuro fuzzy inference system (ANFIS), was introduced in this study. Based on this approach, prior knowledge of a fuzzy inference system can be quickly collected from observation data (clinically used constraints). The learning capability and the accuracy of such a system were analyzed by generating multiple FIS from data collected from an AI system with known settings and rules. Results Multiple analyses showed good agreements of FIS and ANFIS according to rules (error of the output values of ANFIS based on the training data from FIS of 7.77 ± 0.02%) and membership functions (3.9%), thus suggesting that the "behavior" of an FIS can be propagated to another, based on this process. The initial experimental results on a clinical case showed that ANFIS is an effective way to build FIS from practical data, and analysis of ANFIS and FIS with clinical cases showed good planning results provided by ANFIS. OAR volumes encompassed by characteristic percentages of isodoses were reduced by a mean of between 0 and 28%. Conclusion The study demonstrated a

  18. Troposphere Parameters Derived from Multi-GNSS Data Processing at GFZ

    NASA Astrophysics Data System (ADS)

    Deng, Zhiguo; Uhlemann, Maik; Fritsche, Mathias; Dick, Galina; Wickert, Jens

    2015-04-01

    Usually, the processing of Global Navigation Satellite System (GNSS) observations requires a thorough consideration of atmospheric parameters for precise applications. Accordingly, GPS meteorology has become a tool which uses measurements from ground-based GPS receivers for atmospheric water vapor sounding. Zenith total delay (ZTD) products derived from GNSS complement different other meteorological observing systems. GPS-based ZTD estimates have also been assimilated into numerical weather prediction (NWP) models. In addition to GPS and GLONASS, the new and emerging satellite navigation systems BeiDou and Galileo provide the potential for extended and more precise GNSS applications. Accordingly, the International GNSS Service (IGS) has initiated the Multi-GNSS Experiment (MGEX) to acquire and analyze data from all four constellations. In view of the increased number of actively transmitting satellites, the ZTD parameter estimation will particularly benefit from an improved spatial distribution of observations tracked by the ground-based receivers. In this contribution, we report on the status of our multi-system (GPS, GLONASS, BeiDou, Galileo) data processing at GFZ. Based on data from the MGEX network we produce multi-GNSS solutions including parameter estimates for satellite orbits, clock, station coordinates and site-specific ZTDs. Our presentation focusses on the validation of ZTDs from the multi-GNSS processing and a comparison with single-system ZTD solutions and GFZ's operational near real-time troposphere products.

  19. Parameter-free effective field theory calculation for the solar proton-fusion and hep processes

    SciTech Connect

    T.S. Park; L.E. Marcucci; R. Schiavilla; M. Viviani; A. Kievsky; S. Rosati; K. Kubodera; D.P. Min; M. Rho

    2002-08-01

    Spurred by the recent complete determination of the weak currents in two-nucleon systems up to {Omicron}(Q{sup 3}) in heavy-baryon chiral perturbation theory, we carry out a parameter-free calculation of the threshold S-factors for the solar pp (proton-fusion) and hep processes in an effective field theory that combines the merits of the standard nuclear physics method and systematic chiral expansion. The power of the EFT adopted here is that one can correlate in a unified formalism the weak-current matrix elements of two-, three- and four-nucleon systems. Using the tritium {beta}-decay rate as an input to fix the only unknown parameter in the theory, we can evaluate the threshold S factors with drastically improved precision; the results are S{sub pp}(0) = 3.94 x (1 {+-} 0.004) x 10{sup -25} MeV-b and S{sub hep}(0) = (8.6 {+-} 1.3) x 10{sup -20} keV-b. The dependence of the calculated S-factors on the momentum cutoff parameter {Lambda} has been examined for a physically reasonable range of {Lambda}. This dependence is found to be extremely small for the pp process, and to be within acceptable levels for the hep process, substantiating the consistency of our calculational scheme.

  20. Exothermic furnace module development. [space processing

    NASA Technical Reports Server (NTRS)

    Darnell, R. R.; Poorman, R. M.

    1982-01-01

    An exothermic furnace module was developed to rapidly heat and cool a 0.820-in. (2.1 cm) diameter by 2.75-in. (7.0 cm) long TZM molybdenum alloy crucible. The crucible contains copper, oxygen, and carbon for processing in a low-g environment. Peak temperatures of 1270 C were obtainable 3.5 min after start of ignition, and cooling below 950 C some 4.5 min later. These time-temperature relationships were conditioned for a foam-copper experiment, Space Processing Applications Rocket experiment 77-9, in a sounding rocket having a low-g period of 5 min.

  1. Site-specific analysis of radiological and physical parameters for cobbly soils at the Gunnison, Colorado, processing site. Revision 1

    SciTech Connect

    Not Available

    1994-01-01

    The remedial action at the Gunnison, Colorado, processing site is being performed under the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978. Under UMTRCA, the US Environmental Protection Agency (EPA) is charged with the responsibility of developing appropriate and applicable standards for the cleanup of radiologically contaminated land and buildings at 24 designated sites, including the Gunnison, Colorado, inactive processing site. Section 108 of Public Law 95-604 states that the US Department of Energy (DOE) shall ``select and perform remedial actions at the designated processing sites and disposal sites in accordance with the general standards`` prescribed by the EPA. Regulations governing the required remedial action at inactive uranium processing sites were promulgated by the EPA in 1983 and are contained in 40 CFR Part 192 (1993), Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings. This document describes the radiological and physical parameters for the remedial action of the soil.

  2. Influence of in line monitored fluid bed granulation process parameters on the stability of Ethinylestradiol.

    PubMed

    Roßteuscher-Carl, Katrin; Fricke, Sabine; Hacker, Michael C; Schulz-Siegmund, Michaela

    2015-12-30

    Ethinylestradiol (EE) as a highly active and low dosed compound is prone to oxidative degradation. The stability of the drug substance is therefore a critical parameter that has to be considered during drug formulation. Beside the stability of the drug substance, granule particle size and moisture are critical quality attributes (CQA) of the fluid bed granulation process which influence the tableting ability of the resulting granules. Both CQA should therefore be monitored during the production process by process analytic technology (PAT) according to ICH Q8. This work focusses on the effects of drying conditions on the stability of EE in a fluid-bed granulation process. We quantified EE degradation products 6-alpha-hydroxy-EE, 6-beta-hydroxy-EE, 9(11)-dehydro-EE and 6-oxo-EE during long time storage and accelerated conditions. PAT-tools that monitor granule particle size (Spatial filtering technology) and granule moisture (Microwave resonance technology) were applied and compared with off-line methods. We found a relevant influence of residual granule moisture and thermic stress applied during granulation on the storage stability of EE, whereas no degradation was found immediately after processing. Hence we conclude that drying parameters have a relevant influence on long term EE stability. PMID:26541302

  3. Compact Process Development at Babcock & Wilcox

    SciTech Connect

    Eric Shaber; Jeffrey Phillips

    2012-03-01

    Multiple process approaches have been used historically to manufacture cylindrical nuclear fuel compacts. Scale-up of fuel compacting was required for the Next Generation Nuclear Plant (NGNP) project to achieve an economically viable automated production process capable of providing a minimum of 10 compacts/minute with high production yields. In addition, the scale-up effort was required to achieve matrix density equivalent to baseline historical production processes, and allow compacting at fuel packing fractions up to 46% by volume. The scale-up approach of jet milling, fluid-bed overcoating, and hot-press compacting adopted in the U.S. Advanced Gas Reactor (AGR) Fuel Development Program involves significant paradigm shifts to capitalize on distinct advantages in simplicity, yield, and elimination of mixed waste. A series of compaction trials have been completed to optimize compaction conditions of time, temperature, and forming pressure using natural uranium oxycarbide (NUCO) fuel at packing fractions exceeding 46% by volume. Results from these trials are included. The scale-up effort is nearing completion with the process installed and operable using nuclear fuel materials. Final process testing is in progress to certify the process for manufacture of qualification test fuel compacts in 2012.

  4. Development of the selective coagulation process

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1991-01-01

    Recent studies have resulted in the development of a novel agglomeration process for upgrading ultrafine coal. This process, which is known as selective hydrophobic coagulation (SHC), is based on the new finding that hydrophobic coal particles can be selectively coagulated in the presence of dispersed mineral matter. The driving force for the coagulation is believed to be due to the structural arrangement of water molecules near the coal surface. In most cases, simple pH control is all that is required to (1) induce the coagulation of the coal particles and (2) effectively disperse the particles of mineral matter. During the past quarter, several important aspects of the SHC process were examined. Direct measurements of the surface forces which control the selective coagulation process were conducted using a Mark 4 surface force apparatus. These preliminary measurements have provided irrefutable evidence for the existence of the hydrophobic force. Key expressions have been presented for a population balance model describing the hydrophobic coagulation process. In order to validate this model, experimental measurements of the size distributions of coal coagulation have been initiated. The liberation characteristics of samples obtained from the Elkhorn No. 3 and Pittsburgh No. 8 coal seams were determined using a SEM-IPS image processing system. Mixing studies were carried out to determine the effects of mixer-impeller configurations on the coagula size distributions. Bench-scale continuous testing has also been initiated during the past quarter using a rotating drum screen and sedimentation tank. 25 figs., 8 tabs.

  5. Impact of soil parameter and physical process on reproducibility of hydrological processes by land surface model in semiarid grassland

    NASA Astrophysics Data System (ADS)

    Miyazaki, S.; Yorozu, K.; Asanuma, J.; Kondo, M.; Saito, K.

    2014-12-01

    The land surface model (LSM) takes part in the land-atmosphere interaction on the earth system model for the climate change research. In this study, we evaluated the impact of soil parameters and physical process on reproducibility of hydrological process by LSM Minimal Advanced Treatments of Surface Interaction and RunOff (MATSIRO; Takata et al, 2003, GPC) forced by the meteorological data observed at grassland in semiarid climate in China and Mongolia. The testing of MATSIRO was carried out offline mode over the semiarid grassland sites at Tongyu (44.42 deg. N, 122.87 deg. E, altitude: 184m) in China, Kherlen Bayan Ulaan (KBU; 47.21 deg. N, 108.74 deg. E, altitude: 1235m) and Arvaikheer (46.23 N, 102.82E, altitude: 1,813m) in Mongolia. Although all sites locate semiarid grassland, the climate condition is different among sites, which the annual air temperature and precipitation are 5.7 deg. C and 388mm (Tongyu), 1.2 deg.C and 180mm (KBU), and 0.4 deg. C and 245mm(Arvaikheer). We can evaluate the effect of climate condition on the model performance. Three kinds of experiments have been carried out, which was run with the default parameters (CTL), the observed parameters (OBS) for soil physics and hydrology, and vegetation, and refined MATSIRO with the effect of ice in thermal parameters and unfrozen water below the freezing with same parameters as OBS run (OBSr). The validation data has been provided by CEOP(http://www.ceop.net/) , RAISE(http://raise.suiri.tsukuba.ac.jp/), GAME-AAN (Miyazaki et al., 2004, JGR) for Tongyu, KBU, and Arvaikheer, respectively. The reproducibility of the net radiation, the soil temperature (Ts), and latent heat flux (LE) were well reproduced by OBS and OBSr run. The change of soil physical and hydraulic parameter affected the reproducibility of soil temperature (Ts) and soil moisture (SM) as well as energy flux component especially for the sensible heat flux (H) and soil heat flux (G). The reason for the great improvement on the

  6. Quantitative high throughput analytics to support polysaccharide production process development.

    PubMed

    Noyes, Aaron; Godavarti, Ranga; Titchener-Hooker, Nigel; Coffman, Jonathan; Mukhopadhyay, Tarit

    2014-05-19

    The rapid development of purification processes for polysaccharide vaccines is constrained by a lack of analytical tools current technologies for the measurement of polysaccharide recovery and process-related impurity clearance are complex, time-consuming, and generally not amenable to high throughput process development (HTPD). HTPD is envisioned to be central to the improvement of existing polysaccharide manufacturing processes through the identification of critical process parameters that potentially impact the quality attributes of the vaccine and to the development of de novo processes for clinical candidates, across the spectrum of downstream processing. The availability of a fast and automated analytics platform will expand the scope, robustness, and evolution of Design of Experiment (DOE) studies. This paper details recent advances in improving the speed, throughput, and success of in-process analytics at the micro-scale. Two methods, based on modifications of existing procedures, are described for the rapid measurement of polysaccharide titre in microplates without the need for heating steps. A simplification of a commercial endotoxin assay is also described that features a single measurement at room temperature. These assays, along with existing assays for protein and nucleic acids are qualified for deployment in the high throughput screening of polysaccharide feedstreams. Assay accuracy, precision, robustness, interference, and ease of use are assessed and described. In combination, these assays are capable of measuring the product concentration and impurity profile of a microplate of 96 samples in less than one day. This body of work relies on the evaluation of a combination of commercially available and clinically relevant polysaccharides to ensure maximum versatility and reactivity of the final assay suite. Together, these advancements reduce overall process time by up to 30-fold and significantly reduce sample volume over current practices. The

  7. Advanced PPA Reactor and Process Development

    NASA Technical Reports Server (NTRS)

    Wheeler, Raymond; Aske, James; Abney, Morgan B.; Miller, Lee A.; Greenwood, Zachary

    2012-01-01

    Design and development of a second generation Plasma Pyrolysis Assembly (PPA) reactor is currently underway as part of NASA s Atmosphere Revitalization Resource Recovery effort. By recovering up to 75% of the hydrogen currently lost as methane in the Sabatier reactor effluent, the PPA helps to minimize life support resupply costs for extended duration missions. To date, second generation PPA development has demonstrated significant technology advancements over the first generation device by doubling the methane processing rate while, at the same time, more than halving the required power. One development area of particular interest to NASA system engineers is fouling of the PPA reactor with carbonaceous products. As a mitigation plan, NASA MSFC has explored the feasibility of using an oxidative plasma based upon metabolic CO2 to regenerate the reactor window and gas inlet ports. The results and implications of this testing are addressed along with the advanced PPA reactor development work.

  8. Quantitative analysis of beam delivery parameters and treatment process time for proton beam therapy

    SciTech Connect

    Suzuki, Kazumichi; Gillin, Michael T.; Sahoo, Narayan; Zhu, X. Ronald; Lee, Andrew K.; Lippy, Denise

    2011-07-15

    Purpose: To evaluate patient census, equipment clinical availability, maximum daily treatment capacity, use factor for major beam delivery parameters, and treatment process time for actual treatments delivered by proton therapy systems. Methods: The authors have been recording all beam delivery parameters, including delivered dose, energy, range, spread-out Bragg peak widths, gantry angles, and couch angles for every treatment field in an electronic medical record system. We analyzed delivery system downtimes that had been recorded for every equipment failure and associated incidents. These data were used to evaluate the use factor of beam delivery parameters, the size of the patient census, and the equipment clinical availability of the facility. The duration of each treatment session from patient walk-in and to patient walk-out of the treatment room was measured for 82 patients with cancers at various sites. Results: The yearly average equipment clinical availability in the last 3 yrs (June 2007-August 2010) was 97%, which exceeded the target of 95%. Approximately 2200 patients had been treated as of August 2010. The major disease sites were genitourinary (49%), thoracic (25%), central nervous system (22%), and gastrointestinal (2%). Beams have been delivered in approximately 8300 treatment fields. The use factor for six beam delivery parameters was also evaluated. Analysis of the treatment process times indicated that approximately 80% of this time was spent for patient and equipment setup. The other 20% was spent waiting for beam delivery and beam on. The total treatment process time can be expressed by a quadratic polynomial of the number of fields per session. The maximum daily treatment capacity of our facility using the current treatment processes was estimated to be 133 {+-} 35 patients. Conclusions: This analysis shows that the facility has operated at a high performance level and has treated a large number of patients with a variety of diseases. The use

  9. Processed pseudogenes acquired somatically during cancer development.

    PubMed

    Cooke, Susanna L; Shlien, Adam; Marshall, John; Pipinikas, Christodoulos P; Martincorena, Inigo; Tubio, Jose M C; Li, Yilong; Menzies, Andrew; Mudie, Laura; Ramakrishna, Manasa; Yates, Lucy; Davies, Helen; Bolli, Niccolo; Bignell, Graham R; Tarpey, Patrick S; Behjati, Sam; Nik-Zainal, Serena; Papaemmanuil, Elli; Teixeira, Vitor H; Raine, Keiran; O'Meara, Sarah; Dodoran, Maryam S; Teague, Jon W; Butler, Adam P; Iacobuzio-Donahue, Christine; Santarius, Thomas; Grundy, Richard G; Malkin, David; Greaves, Mel; Munshi, Nikhil; Flanagan, Adrienne M; Bowtell, David; Martin, Sancha; Larsimont, Denis; Reis-Filho, Jorge S; Boussioutas, Alex; Taylor, Jack A; Hayes, Neil D; Janes, Sam M; Futreal, P Andrew; Stratton, Michael R; McDermott, Ultan; Campbell, Peter J

    2014-01-01

    Cancer evolves by mutation, with somatic reactivation of retrotransposons being one such mutational process. Germline retrotransposition can cause processed pseudogenes, but whether this occurs somatically has not been evaluated. Here we screen sequencing data from 660 cancer samples for somatically acquired pseudogenes. We find 42 events in 17 samples, especially non-small cell lung cancer (5/27) and colorectal cancer (2/11). Genomic features mirror those of germline LINE element retrotranspositions, with frequent target-site duplications (67%), consensus TTTTAA sites at insertion points, inverted rearrangements (21%), 5' truncation (74%) and polyA tails (88%). Transcriptional consequences include expression of pseudogenes from UTRs or introns of target genes. In addition, a somatic pseudogene that integrated into the promoter and first exon of the tumour suppressor gene, MGA, abrogated expression from that allele. Thus, formation of processed pseudogenes represents a new class of mutation occurring during cancer development, with potentially diverse functional consequences depending on genomic context. PMID:24714652

  10. Processed pseudogenes acquired somatically during cancer development

    PubMed Central

    Cooke, Susanna L.; Shlien, Adam; Marshall, John; Pipinikas, Christodoulos P.; Martincorena, Inigo; Tubio, Jose M.C.; Li, Yilong; Menzies, Andrew; Mudie, Laura; Ramakrishna, Manasa; Yates, Lucy; Davies, Helen; Bolli, Niccolo; Bignell, Graham R.; Tarpey, Patrick S.; Behjati, Sam; Nik-Zainal, Serena; Papaemmanuil, Elli; Teixeira, Vitor H.; Raine, Keiran; O’Meara, Sarah; Dodoran, Maryam S.; Teague, Jon W.; Butler, Adam P.; Iacobuzio-Donahue, Christine; Santarius, Thomas; Grundy, Richard G.; Malkin, David; Greaves, Mel; Munshi, Nikhil; Flanagan, Adrienne M.; Bowtell, David; Martin, Sancha; Larsimont, Denis; Reis-Filho, Jorge S.; Boussioutas, Alex; Taylor, Jack A.; Hayes, Neil D.; Janes, Sam M.; Futreal, P. Andrew; Stratton, Michael R.; McDermott, Ultan; Campbell, Peter J.; Provenzano, Elena; van de Vijver, Marc; Richardson, Andrea L.; Purdie, Colin; Pinder, Sarah; Mac Grogan, Gaetan; Vincent-Salomon, Anne; Larsimont, Denis; Grabau, Dorthe; Sauer, Torill; Garred, Øystein; Ehinger, Anna; Van den Eynden, Gert G.; van Deurzen, C.H.M; Salgado, Roberto; Brock, Jane E.; Lakhani, Sunil R.; Giri, Dilip D.; Arnould, Laurent; Jacquemier, Jocelyne; Treilleux, Isabelle; Caldas, Carlos; Chin, Suet-Feung; Fatima, Aquila; Thompson, Alastair M.; Stenhouse, Alasdair; Foekens, John; Martens, John; Sieuwerts, Anieta; Brinkman, Arjen; Stunnenberg, Henk; Span, Paul N.; Sweep, Fred; Desmedt, Christine; Sotiriou, Christos; Thomas, Gilles; Broeks, Annegein; Langerod, Anita; Aparicio, Samuel; Simpson, Peter T.; van ’t Veer, Laura; Erla Eyfjörd, Jórunn; Hilmarsdottir, Holmfridur; Jonasson, Jon G.; Børresen-Dale, Anne-Lise; Lee, Ming Ta Michael; Wong, Bernice Huimin; Tan, Benita Kiat Tee; Hooijer, Gerrit K.J.

    2014-01-01

    Cancer evolves by mutation, with somatic reactivation of retrotransposons being one such mutational process. Germline retrotransposition can cause processed pseudogenes, but whether this occurs somatically has not been evaluated. Here we screen sequencing data from 660 cancer samples for somatically acquired pseudogenes. We find 42 events in 17 samples, especially non-small cell lung cancer (5/27) and colorectal cancer (2/11). Genomic features mirror those of germline LINE element retrotranspositions, with frequent target-site duplications (67%), consensus TTTTAA sites at insertion points, inverted rearrangements (21%), 5′ truncation (74%) and polyA tails (88%). Transcriptional consequences include expression of pseudogenes from UTRs or introns of target genes. In addition, a somatic pseudogene that integrated into the promoter and first exon of the tumour suppressor gene, MGA, abrogated expression from that allele. Thus, formation of processed pseudogenes represents a new class of mutation occurring during cancer development, with potentially diverse functional consequences depending on genomic context. PMID:24714652

  11. Processing of thermal parameters for the assessment of geothermal potential of sedimentary basins

    NASA Astrophysics Data System (ADS)

    Pasquale, V.; Chiozzi, P.; Gola, G.; Verdoya, M.

    2009-04-01

    The growing interest on renewable energy sources is stimulating new efforts aimed at the assessment of geothermal potential in several countries, and new developments are expected in the near future. In this framework, a basic step forward is to focus geothermal investigations on geological environments which so far have been relatively neglected. Some intracontinental sedimentary basins could reveal important low enthalpy resources. The evaluation of the geothermal potential in such geological contexts involves the synergic use of geophysical and hydrogeological methodologies. In sedimentary basins a large amount of thermal and hydraulic data is generally available from petroleum wells. Unfortunately, borehole temperature data are often affected by a number of perturbations which make very difficult determination of the true geothermal gradient. In this paper we addressed the importance of the acquisition of thermal parameters (temperature, geothermal gradient, thermal properties of the rock) and the technical processing which is necessary to obtain reliable geothermal characterizations. In particular, techniques for corrections of bottom-hole temperature (BHT) data were reviewed. The objective was to create a working formula usable for computing the undisturbed formation temperature for specific sedimentary basins. As test areas, we analysed the sedimentary basins of northern Italy. Two classical techniques for processing temperature data from oil wells are customarily used: (i) the method by Horner, that requires two or more measurements of bottom-hole temperatures carried out at the same depth but at different shut-in times te and (ii) the technique by Cooper and Jones, in which several physical parameters of the mud and formation need to be known. We applied both methods to data from a number of petroleum explorative wells located in two areas of the Po Plain (Apenninic buried arc and South Piedmont Basin - Pedealpine homocline). From a set of about 40 wells

  12. Modeling and Analysis of Process Parameters for Evaluating Shrinkage Problems During Plastic Injection Molding of a DVD-ROM Cover

    NASA Astrophysics Data System (ADS)

    Öktem, H.

    2012-01-01

    Plastic injection molding plays a key role in the production of high-quality plastic parts. Shrinkage is one of the most significant problems of a plastic part in terms of quality in the plastic injection molding. This article focuses on the study of the modeling and analysis of the effects of process parameters on the shrinkage by evaluating the quality of the plastic part of a DVD-ROM cover made with Acrylonitrile Butadiene Styrene (ABS) polymer material. An effective regression model was developed to determine the mathematical relationship between the process parameters (mold temperature, melt temperature, injection pressure, injection time, and cooling time) and the volumetric shrinkage by utilizing the analysis data. Finite element (FE) analyses designed by Taguchi (L27) orthogonal arrays were run in the Moldflow simulation program. Analysis of variance (ANOVA) was then performed to check the adequacy of the regression model and to determine the effect of the process parameters on the shrinkage. Experiments were conducted to control the accuracy of the regression model with the FE analyses obtained from Moldflow. The results show that the regression model agrees very well with the FE analyses and the experiments. From this, it can be concluded that this study succeeded in modeling the shrinkage problem in our application.

  13. Design of experiments reveals critical parameters for pilot-scale freeze-and-thaw processing of L-lactic dehydrogenase.

    PubMed

    Roessl, Ulrich; Humi, Sebastian; Leitgeb, Stefan; Nidetzky, Bernd

    2015-09-01

    Freezing constitutes an important unit operation of biotechnological protein production. Effects of freeze-and-thaw (F/T) process parameters on stability and other quality attributes of the protein product are usually not well understood. Here a design of experiments (DoE) approach was used to characterize the F/T behavior of L-lactic dehydrogenase (LDH) in a 700-mL pilot-scale freeze container equipped with internal temperature and pH probes. In 24-hour experiments, target temperature between -10 and -38°C most strongly affected LDH stability whereby enzyme activity was retained best at the highest temperature of -10°C. Cooling profile and liquid fill volume also had significant effects on LDH stability and affected the protein aggregation significantly. Parameters of the thawing phase had a comparably small effect on LDH stability. Experiments in which the standard sodium phosphate buffer was exchanged by Tris-HCl and the non-ionic surfactant Tween 80 was added to the protein solution showed that pH shift during freezing and protein surface exposure were the main factors responsible for LDH instability at the lower freeze temperatures. Collectively, evidence is presented that supports the use of DoE-based systematic analysis at pilot scale in the identification of F/T process parameters critical for protein stability and in the development of suitable process control strategies. PMID:25820483

  14. Controlled drug release from melt-extrudates through processing parameters: a chemometric approach.

    PubMed

    Sarraf, Abraham G; Cherkaoui, Samir; Jordan, Olivier; Gurny, Robert; Doelker, Eric

    2015-03-15

    The objective of this study was to tailor a drug release profile through the adjustment of some key processing parameters involved in melt-extrusion: die temperature, shear rate, die length and drug particle size. Two experimental designs were selected, namely a 2-level full factorial design to examine the effects and significance of the processing factors, and a central composite design of the surface responses to find the best set of factor levels to obtain given specifications of drug release. Extrudates of poly(ethylene-co-vinyl acetate) and phenylpropanolamine hydrochloride were prepared using a ram extruder. Drug release profiles from the matrix systems were fitted using a power law, for which a new mathematical expression of a burst release was provided. The burst release and exponent were selected as the responses. The processing factors had a drastic influence on the drug release. Within the domain that was investigated, the burst release and the exponent varied from 6 to 54% and 0.1 to 0.4, respectively, resulting in a time requires for 50% drug release extending from hours to weeks. These results demonstrated the possibilities of modulating the release profile by means of the processing parameters rather than through the classical approach of altering the formulation. PMID:25543111

  15. Display device for indicating the value of a parameter in a process plant

    DOEpatents

    Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

    1993-01-01

    An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.

  16. Development of NIL processes for PV applications

    NASA Astrophysics Data System (ADS)

    Hauser, H.; Tucher, N.; Tokai, K.; Schneider, P.; Wellens, Ch.; Volk, A.; Barke, S.; Müller, C.; Glinsner, T.; Bläsi, B.

    2015-03-01

    Due to its high resolution and applicability for large area patterning, Nanoimprint Lithography (NIL) is a promising technology for photovoltaic (PV) applications. However, a successful industrial application of NIL processes is only possible if large-area processing on thin, brittle and potentially rough substrates can be achieved in a high-throughput process. In this work, the development of NIL processes using the novel SmartNILTM technology from EV Group with a focus on PV applications is described. We applied this tooling to realize a honeycomb texture (8 μm period) on the front side of multicrystalline silicon solar cells leading to an improvement in optical efficiency of 7% relative and a total efficiency gain of 0.5% absolute compared to the industrial standard texture (isotexture). On the rear side of monocrystalline silicon solar cells, we realized diffraction gratings to make use of light trapping effects. An absorption enhancement of up to 35% absolute at a wavelength of 1100 nm is demonstrated. Furthermore, we combined photolithography and NIL processes to introduce features for metal contacts into honeycomb master structures, which initially were realized using interference lithography. As final application, we investigated the realization of very fine contact fingers with prismatic shape in order to minimize reflection losses.

  17. Development of nanoimprint processes for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Hauser, Hubert; Tucher, Nico; Tokai, Katharina; Schneider, Patrick; Wellens, Christine; Volk, Anne; Seitz, Sonja; Benick, Jan; Barke, Simon; Dimroth, Frank; Müller, Claas; Glinsner, Thomas; Bläsi, Benedikt

    2015-07-01

    Due to its high resolution and applicability for large area patterning, nanoimprint lithography (NIL) is a promising technology for photovoltaic (PV) applications. However, a successful industrial application of NIL processes is only possible if large-area processing on thin, brittle, and potentially rough substrates can be achieved in a high-throughput process. The development of NIL processes using the SmartNIL technology from EV Group with a focus on PV applications is described. The authors applied this tooling to realize a honeycomb texture (8 μm period) on the front side of multicrystalline silicon solar cells, leading to an improvement in optical efficiency of 7% relative and a total efficiency gain of 0.5% absolute compared to the industrial standard texture (isotexture). On the rear side of monocrystalline silicon solar cells, the authors realized diffraction gratings to make use of light trapping effects. An absorption enhancement of up to 35% absolute at a wavelength of 1100 nm is demonstrated. Furthermore, photolithography was combined with NIL processes to introduce features for metal contacts into honeycomb master structures, which were initially realized using interference lithography. As a final application, the authors investigated the realization of very fine contact fingers with prismatic shape in order to minimize reflection losses.

  18. Relationships Between LRI Process Parameters and Impact and Post-Impact Behaviour of Stitched and Unstitched NCF Laminates

    NASA Astrophysics Data System (ADS)

    Njionhou, Alvine; Berthet, Florentin; Castanié, Bruno; Bouvet, Christophe

    2012-12-01

    The general context of the development of out-of-autoclave processes in the aeronautics industry raises the question of the possible links between these new processes and impact behaviour. In this study, a Taguchi table was used in a design of experiment approach to establish possible links. The study focused on the liquid resin infusion process applied to laminates made with stitched or unstitched quadri-axial carbon Non-Crimp Fabric (NCF). On the basis of previous studies and an analysis of the literature, five process parameters were selected (stitching, curing temperature, preform position, number of highly porous media, vacuum level). The impact energy was set at 35 J in order to obtain enough residual dent depth. The parameters analysed during and after impact were: maximum displacement of the impactor, energy absorbed, permanent indentation depth, and delaminated surface. Then, compression after impact tests were performed and the corresponding average stress was measured. The interactions found by statistical analysis show a very high sensitivity to stitching, which was, of course, expected. A very significant influence of curing temperature and a significant influence of preform position were also found on the permanent indentation depth and a physical explanation is provided. Globally, it was demonstrated that the resin infusion process itself did not influence the impact behaviour.

  19. Estimation of the soil strength parameters in Tertiary volcanic regolith (NE Turkey) using analytical hierarchy process

    NASA Astrophysics Data System (ADS)

    Ersoy, Hakan; Karsli, Melek Betül; Çellek, Seda; Kul, Bilgehan; Baykan, İdris; Parsons, Robert L.

    2013-12-01

    Costly and time consuming testing techniques and the difficulties in providing undisturbed samples for these tests have led researchers to estimate strength parameters of soils with simple index tests. However, the paper focuses on estimation of strength parameters of soils as a function of the index properties. Analytical hierarchy process and multiple regression analysis based methodology were performed on datasets obtained from soil tests on 41 samples in Tertiary volcanic regolith. While the hierarchy model focused on determining the most important index properties affecting on strength parameters, regression analysis established meaningful relationships between strength parameters and index properties. The negative polynomial correlations between the friction angle and plasticity properties, and the positive exponential relations between the cohesion and plasticity properties were determined. These relations are characterized by a regression coefficient of 0.80. However, Terzaghi bearing capacity formulas were used to test the model. It is important to see whether there is any statistically significant relation between the calculated and the observed bearing capacity values for model testing. Based on the model, the positive linear correlation characterized by the regression coefficient of 0.86 were determined between bearing capacity values obtained by direct and indirect methods.

  20. A self-adaptive parameter optimization algorithm in a real-time parallel image processing system.

    PubMed

    Li, Ge; Zhang, Xuehe; Zhao, Jie; Zhang, Hongli; Ye, Jianwei; Zhang, Weizhe

    2013-01-01

    Aiming at the stalemate that precision, speed, robustness, and other parameters constrain each other in the parallel processed vision servo system, this paper proposed an adaptive load capacity balance strategy on the servo parameters optimization algorithm (ALBPO) to improve the computing precision and to achieve high detection ratio while not reducing the servo circle. We use load capacity functions (LC) to estimate the load for each processor and then make continuous self-adaptation towards a balanced status based on the fluctuated LC results; meanwhile, we pick up a proper set of target detection and location parameters according to the results of LC. Compared with current load balance algorithm, the algorithm proposed in this paper is proceeded under an unknown informed status about the maximum load and the current load of the processors, which means it has great extensibility. Simulation results showed that the ALBPO algorithm has great merits on load balance performance, realizing the optimization of QoS for each processor, fulfilling the balance requirements of servo circle, precision, and robustness of the parallel processed vision servo system. PMID:24174920

  1. Effective parameters, effective processes: From porous flow physics to in situ remediation technology

    SciTech Connect

    Pruess, K.

    1995-06-01

    This paper examines the conceptualization of multiphase flow processes on the macroscale, as needed in field applications. It emphasizes that upscaling from the pore-level will in general not only introduce effective parameters but will also give rise to ``effective processes,`` i.e., the emergence of new physical effects that may not have a microscopic counterpart. ``Phase dispersion`` is discussed as an example of an effective process for the migration and remediation of non-aqueous phase liquid (NAPL) contaminants in heterogeneous media. An approximate space-and-time scaling invariance is derived for gravity-driven liquid flow in unsaturated two-dimensional porous media (fractures). Issues for future experimental and theoretical work are identified.

  2. DEVELOPMENT OF A LUMPED-PARAMETER MODEL OF INDOOR RADON CONCENTRATIONS

    EPA Science Inventory

    The report describes a simplified, lumped-parameter model to characterize indoor radon concentrations from data that are more readily available than those required for existing mathematical models. he lumped-parameter model was developed from numerous sensitivity analyses with th...

  3. Application of GA-SVM method with parameter optimization for landslide development prediction

    NASA Astrophysics Data System (ADS)

    Li, X. Z.; Kong, J. M.

    2014-03-01

    Prediction of the landslide development process is always a hot issue in landslide research. So far, many methods for landslide displacement series prediction have been proposed. The support vector machine (SVM) has been proved to be a novel algorithm with good performance. However, the performance strongly depends on the right selection of the parameters (C and γ) of the SVM model. In this study, we present an application of genetic algorithm and support vector machine (GA-SVM) method with parameter optimization in landslide displacement rate prediction. We selected a typical large-scale landslide in a hydro-electrical engineering area of southwest China as a case. On the basis of analyzing the basic characteristics and monitoring data of the landslide, a single-factor GA-SVM model and a multi-factor GA-SVM model of the landslide were built. Moreover, the models were compared with single-factor and multi-factor SVM models of the landslide. The results show that the four models have high prediction accuracies, but the accuracies of GA-SVM models are slightly higher than those of SVM models, and the accuracies of multi-factor models are slightly higher than those of single-factor models for the landslide prediction. The accuracy of the multi-factor GA-SVM models is the highest, with the smallest root mean square error (RMSE) of 0.0009 and the highest relation index (RI) of 0.9992.

  4. Application of GA-SVM method with parameter optimization for landslide development prediction

    NASA Astrophysics Data System (ADS)

    Li, X. Z.; Kong, J. M.

    2013-10-01

    Prediction of landslide development process is always a hot issue in landslide research. So far, many methods for landslide displacement series prediction have been proposed. Support vector machine (SVM) has been proved to be a novel algorithm with good performance. However, the performance strongly depends on the right selection of the parameters (C and γ) of SVM model. In this study, we presented an application of GA-SVM method with parameter optimization in landslide displacement rate prediction. We selected a typical large-scale landslide in some hydro - electrical engineering area of Southwest China as a case. On the basis of analyzing the basic characteristics and monitoring data of the landslide, a single-factor GA-SVM model and a multi-factor GA-SVM model of the landslide were built. Moreover, the models were compared with single-factor and multi-factor SVM models of the landslide. The results show that, the four models have high prediction accuracies, but the accuracies of GA-SVM models are slightly higher than those of SVM models and the accuracies of multi-factor models are slightly higher than those of single-factor models for the landslide prediction. The accuracy of the multi-factor GA-SVM models is the highest, with the smallest RSME of 0.0009 and the biggest RI of 0.9992.

  5. Consolidation processing parameters and alternative processing methods for powder metallurgy Al-Cu-Mg-X-X alloys

    NASA Technical Reports Server (NTRS)

    Sankaran, K. K.

    1987-01-01

    The effects of varying the vacuum degassing parameters on the microstructure and properties of Al-4Cu-1Mg-X-X (X-X = 1.5Li-0.2Zr or 1.5Fe-0.75Ce) alloys processed from either prealloyed (PA) or mechanically alloyed (M) powder, and consolidated by either using sealed aluminum containers or containerless vacuum hot pressing were studied. The consolidated billets were hot extruded to evaluate microstructure and properties. The MA Li-containing alloy did not include Zr, and the MA Fe- and Ce-containing alloy was made from both elemental and partially prealloyed powder. The alloys were vacuum degassed both above and below the solution heat treatment temperature. While vacuum degassing lowered the hydrogen content of these alloys, the range over which the vacuum degassing parameters were varied was not large enough to cause significant changes in degassing efficiency, and the observed variations in the mechanical properties of the heat treated alloys were attributed to varying contributions to strengthening by the sub-structure and the dispersoids. Mechanical alloying increased the strength over that of alloys of similar composition made from PA powder. The inferior properties in the transverse orientation, especially in the Li-containing alloys, suggested deficiencies in degassing. Among all of the alloys processed for this study, the Fe- and Ce-containing alloys made from MA powder possessed better combinations of strength and toughness.

  6. A GRAPHICS PROCESSING UNIT-ENABLED, HIGH-RESOLUTION COSMOLOGICAL MICROLENSING PARAMETER SURVEY

    SciTech Connect

    Bate, N. F.; Fluke, C. J.

    2012-01-10

    In the era of synoptic surveys, the number of known gravitationally lensed quasars is set to increase by over an order of magnitude. These new discoveries will enable a move from single-quasar studies to investigations of statistical samples, presenting new opportunities to test theoretical models for the structure of quasar accretion disks and broad emission line regions (BELRs). As one crucial step in preparing for this influx of new lensed systems, a large-scale exploration of microlensing convergence-shear parameter space is warranted, requiring the computation of O(10{sup 5}) high-resolution magnification maps. Based on properties of known lensed quasars, and expectations from accretion disk/BELR modeling, we identify regions of convergence-shear parameter space, map sizes, smooth matter fractions, and pixel resolutions that should be covered. We describe how the computationally time-consuming task of producing {approx}290,000 magnification maps with sufficient resolution (10,000{sup 2} pixel map{sup -1}) to probe scales from the inner edge of the accretion disk to the BELR can be achieved in {approx}400 days on a 100 teraflop s{sup -1} high-performance computing facility, where the processing performance is achieved with graphics processing units. We illustrate a use-case for the parameter survey by investigating the effects of varying the lens macro-model on accretion disk constraints in the lensed quasar Q2237+0305. We find that although all constraints are consistent within their current error bars, models with more densely packed microlenses tend to predict shallower accretion disk radial temperature profiles. With a large parameter survey such as the one described here, such systematics on microlensing measurements could be fully explored.

  7. Aging Processes and the Development of Osteoarthritis

    PubMed Central

    Loeser, Richard F.

    2013-01-01

    Purpose of review Aging is a primary risk factor for the development of osteoarthritis (OA) and the understanding of how aging processes contribute to the development of OA is an important area of active research. The most recent literature in this area was reviewed in order update investigators on the status of the field. Recent findings The field is beginning to move beyond a cartilage focus to include other joint tissues relevant to OA such as ligaments, meniscus, and bone. Synovitis also appears to play a role in OA but has not been a focus of aging studies. Studies in small animals, including mice and rats, demonstrate age-related changes that can contribute to OA and show that animal age is a key factor to be considered in interpreting the results of studies using surgically-induced models of OA. There is accumulating evidence that cellular processes such as damage-induced cell senescence contribute to OA and a growing body of literature on the role of epigenetic regulation of gene expression in aging and OA. Summary Not all OA is due to aging processes in joint tissues but the age-related changes being discovered certainly could play a major contributing role. PMID:23080227

  8. Development of the selective hydrophobic coagulation process

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1992-01-01

    A novel technique for selectively coagulating and separating coal from dispersed mineral matter has been developed at Virginia Tech. The process, Selective Hydrophobic Coagulation (SHC), has been studied since 1986 under the sponsorship of the US Department of Energy. The SHC process differs from oil agglomeration, shear or polymer flocculation, and electrolytic coagulation processes in that it does not require reagents or additives to induce the formation of coagula. In most cases, simple pH control is all that is required to (i) induce the coagulation of coal particles and (ii) effectively disperse particles of mineral matter. If the coal is oxidized, a small dosage of reagents can be used to enhance the process. The technical work program was initiated on July 1, 1992. Force-distance curves were generated for DDOA Br-coated mica surfaces in water and used to calculate hydrophobicity constants and decay lengths for this system; and a new device for the measurement of water contact angles, similar to the Wilhelmy plate balance, has been built 225 kg samples of Pittsburgh No. 8 and Elkhom No. 3 seam coals were obtained; a static mixer test facility for the study of coagula growth was set up and was undergoing shakedown tests at the end of the quarter; a bench-scale lamella thickener was being constructed; and preliminary coagula/ mineral separation tests were being conducted in a bench-scale continuous drum filter.

  9. Development of the Selective Hydrophobic Coagulation process

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1992-01-01

    A novel technique for selectively coagulating and separating coal from dispersed mineral matter has been developed at Virginia Tech. The process, Selective Hydrophobic Coagulation (SHC), has been studied since 1986 under the sponsorship of the US Department of Energy (Contracts AC22-86PC91221 and AC22-90PC90174). The SHC process differs from oil agglomeration, shear or polymer flocculation, and electrolytic coagulation processes in that it does not require reagents or additives to induce the formation of coagula. In most cases, simple pH control is all that is required to (1) induce the coagulation of coal particles and (2) effectively disperse particles of mineral matter. If the coal is oxidized, a small dosage of reagents can be used to enhance the process. During the quarter, the Anutech Mark IV surface force apparatus was used to generate surface force-distance data for the mica/dodecylamine hydrochloride system (Task 2.1.1). Work to characterize the hydrophobicity of this system and the mica/DDOA[sup [minus

  10. Tubeless evaporation process development: Final report

    SciTech Connect

    Not Available

    1987-12-01

    A tubeless evaporation process which has the potential to combine the advantage of both evaporation and freezing processes, without their disadvantages is being developed. The TEP is capable of concentrating process solutions of such things as sugar, caustic soda, salt, sodium sulfate, black liquor from the pulp and paper industry, cooling tower blowdown, ''spent'' pickling liquor (sulfuric acid) from the steel industry, and nitric acid with potential energy savings of half to three-quarters of the energy required by conventional evaporators, with about half of the capital and maintenance cost. It has similar potential for the production of fresh water from seawater. The process uses working fluids (WF's) at their freezing point to effect direct contact heat exchange. The purpose of this project was to find additional and lower cost WF's in the laboratory, to obtain sizing information for the major equipment for an economic evaluation and a pilot plant design in a bench scale plant, and to perform the economic evaluation, and the pilot plant design and cost estimate. 6 refs., 37 figs., 7 tabs.

  11. Simulation of shot peening: From process parameters to residual stress fields in a structure

    NASA Astrophysics Data System (ADS)

    Gallitelli, Donato; Boyer, Vincent; Gelineau, Maxime; Colaitis, Yann; Rouhaud, Emmanuelle; Retraint, Delphine; Kubler, Régis; Desvignes, Marc; Barrallier, Laurent

    2016-04-01

    Manufacturing industries perform mechanical surface treatments like shot peening at the end of the manufacturing chain to protect important working parts. This treatment modifies the near surface of the treated part with the introduction of compressive residual stresses due to the repeated impacts of the shot. Then, the treated part exhibits, not only a longer life, but also a better fretting behavior, an improved resistance to corrosion… The objective of the present paper is first to study the relation between the process parameters and the material state (residual stress and plastic variables…) for a complex geometry. Next, a numerical tool is proposed, able to predict this material state in a time frame that is consistent with industrial constraints. The originality of the proposed approach thus consists in the chaining of the different steps. The first step is to choose the process parameters for the shot peening process considering conventional or ultrasonic shot peening and model the shot dynamics for a complex geometry. Once the impact velocity field is known, the objective is to compute the local incompatible plastic deformation field due to the repeated impacts using analytical methods. Then, a finite element model is used to compute the residual and deformation fields in the considered mechanical part. The complete method has been performed on the model of a gear, a mechanical part that is most often shot peened and exhibits a complex geometry.

  12. Beer fermentation: monitoring of process parameters by FT-NIR and multivariate data analysis.

    PubMed

    Grassi, Silvia; Amigo, José Manuel; Lyndgaard, Christian Bøge; Foschino, Roberto; Casiraghi, Ernestina

    2014-07-15

    This work investigates the capability of Fourier-Transform near infrared (FT-NIR) spectroscopy to monitor and assess process parameters in beer fermentation at different operative conditions. For this purpose, the fermentation of wort with two different yeast strains and at different temperatures was monitored for nine days by FT-NIR. To correlate the collected spectra with °Brix, pH and biomass, different multivariate data methodologies were applied. Principal component analysis (PCA), partial least squares (PLS) and locally weighted regression (LWR) were used to assess the relationship between FT-NIR spectra and the abovementioned process parameters that define the beer fermentation. The accuracy and robustness of the obtained results clearly show the suitability of FT-NIR spectroscopy, combined with multivariate data analysis, to be used as a quality control tool in the beer fermentation process. FT-NIR spectroscopy, when combined with LWR, demonstrates to be a perfectly suitable quantitative method to be implemented in the production of beer. PMID:24594186

  13. Sensitivity analysis of a dry-processed Candu fuel pellet's design parameters

    SciTech Connect

    Choi, Hangbok; Ryu, Ho Jin

    2007-07-01

    Sensitivity analysis was carried out in order to investigate the effect of a fuel pellet's design parameters on the performance of a dry-processed Canada deuterium uranium (CANDU) fuel and to suggest the optimum design modifications. Under a normal operating condition, a dry-processed fuel has a higher internal pressure and plastic strain due to a higher fuel centerline temperature when compared with a standard natural uranium CANDU fuel. Under a condition that the fuel bundle dimensions do not change, sensitivity calculations were performed on a fuel's design parameters such as the axial gap, dish depth, gap clearance and plenum volume. The results showed that the internal pressure and plastic strain of the cladding were most effectively reduced if a fuel's element plenum volume was increased. More specifically, the internal pressure and plastic strain of the dry-processed fuel satisfied the design limits of a standard CANDU fuel when the plenum volume was increased by one half a pellet, 0.5 mm{sup 3}/K. (authors)

  14. Process development for cladding APT tungsten targets

    SciTech Connect

    Horner, M H; Barber, R; Dalder, E

    2000-11-27

    This report describes development of processes for cladding APT Target tungsten components with a thin layer (0.127-mm) of Alloy 718, Alloy 600 or 316L stainless steel alloy. The application requires that the cladding be thermally bonded to the tungsten in order to transfer heat generated in the tungsten volume to a surrounding coolant. High temperature diffusion bonding using the hot isostatic processing (HIP) technique was selected as the method for creating a metallurgical bond between pure tungsten tubes and rods and the cladding materials. Bonding studies using a uniaxially loaded vacuum hot press were conducted in preliminary experiments to determine acceptable time-temperature conditions for diffusion bonding. The results were successfully applied in cladding tungsten rods and tubes with these alloys. Temperatures 800-810 C were suitable for cladding tungsten with Alloy 600 and 316L stainless steel alloy, whereas tungsten was clad with Alloy 718 at 1020 C.

  15. System Development by Process Integrated Knowledge Management

    NASA Astrophysics Data System (ADS)

    Stoll, Margareth; Laner, Dietmar

    Due to globalization and ever shorter change cycle's organizations improve increasingly faster their products, services, technologies, IT and organization according to customer requirements, optimize their efficiency, effectiveness and reduce costs. Thus the largest potential is the continually improvement and the management of information, data and knowledge. Long time organizations had developed lot separate and frequently independent IT applications. In the last years they were integrated by interfaces and always more by common databases. In large sized enterprises or in the public administration IT must operate various different applications, which requires a lot of personal and cost. Many organizations improve their IT starting from the lived processes using new technologies, but ask not, how they can use technology to support new processes.

  16. Impact of Baryonic Processes on Weak-lensing Cosmology: Power Spectrum, Nonlocal Statistics, and Parameter Bias

    NASA Astrophysics Data System (ADS)

    Osato, Ken; Shirasaki, Masato; Yoshida, Naoki

    2015-06-01

    We study the impact of baryonic physics on cosmological parameter estimation with weak-lensing surveys. We run a set of cosmological hydrodynamics simulations with different galaxy formation models. We then perform ray-tracing simulations through the total matter density field to generate 100 independent convergence maps with a field of view of 25 {{deg }2}, and we use them to examine the ability of the following three lensing statistics as cosmological probes: power spectrum (PS), peak counts, and Minkowski functionals (MFs). For the upcoming wide-field observations, such as the Subaru Hyper Suprime-Cam (HSC) survey with a sky coverage of 1400 {{deg }2}, these three statistics provide tight constraints on the matter density, density fluctuation amplitude, and dark energy equation of state, but parameter bias is induced by baryonic processes such as gas cooling and stellar feedback. When we use PS, peak counts, and MFs, the magnitude of relative bias in the dark energy equation of state parameter w is at a level of, respectively, δ w∼ 0.017, 0.061, and 0.0011. For the HSC survey, these values are smaller than the statistical errors estimated from Fisher analysis. The bias could be significant when the statistical errors become small in future observations with a much larger survey area. We find that the bias is induced in different directions in the parameter space depending on the statistics employed. While the two-point statistic, i.e., PS, yields robust results against baryonic effects, the overall constraining power is weak compared with peak counts and MFs. On the other hand, using one of peak counts or MFs, or combined analysis with multiple statistics, results in a biased parameter estimate. The bias can be as large as 1σ for the HSC survey and will be more significant for upcoming wider-area surveys. We suggest to use an optimized combination so that the baryonic effects on parameter estimation are mitigated. Such a “calibrated” combination can

  17. Effect of process parameters on the chemical vapour synthesis of nanocrystalline titania

    NASA Astrophysics Data System (ADS)

    Md, Imteyaz Ahmad; Bhattacharya, S. S.

    2008-08-01

    In this investigation nanocrystalline titania powders were produced by the chemical vapour synthesis (CVS) route and characterized by standard techniques of XRD, HRTEM and BET. The effects of precursor/gas flow rates, hotwall temperature and system pressure on the particle size and distribution, as well as phase composition of the synthesized nanocrystalline titania powder, were studied. It was demonstrated that by suitably adjusting the process parameters during CVS it becomes possible to control the anatase crystallite size, specific surface area and the rutile content in the synthesized nanocrystalline titania powders.

  18. Formulation and implementation of a practical algorithm for parameter estimation with process and measurement noise

    NASA Technical Reports Server (NTRS)

    Maine, R. E.; Iliff, K. W.

    1980-01-01

    A new formulation is proposed for the problem of parameter estimation of dynamic systems with both process and measurement noise. The formulation gives estimates that are maximum likelihood asymptotically in time. The means used to overcome the difficulties encountered by previous formulations are discussed. It is then shown how the proposed formulation can be efficiently implemented in a computer program. A computer program using the proposed formulation is available in a form suitable for routine application. Examples with simulated and real data are given to illustrate that the program works well.

  19. Influence of Process Parameters on Forming of Arched Aircraft Skin with Aluminum Alloy 2024

    NASA Astrophysics Data System (ADS)

    Yan, Huajun; Zhang, Shuangjie; Gao, Ying

    To solve these problems such as easily springback and hardly controlling the loading direction when arched aircraft skin is formed, stretch forming of steel plate with aluminium alloy 2024 was simulated by the finite element software Abaqus, and the shape of the stretch forming die was the arc with radius 350mm. The influence of process parameters, such as stretch forming track and dangling length on forming of arched aircraft skin was researched, and the reasonable range of stretch forming length track and dangling length was given. The results have significance for research the forming law of arched aircraft skin.

  20. Skylab materials processing facility experiment developer's report

    NASA Technical Reports Server (NTRS)

    Parks, P. G.

    1975-01-01

    The development of the Skylab M512 Materials Processing Facility is traced from the design of a portable, self-contained electron beam welding system for terrestrial applications to the highly complex experiment system ultimately developed for three Skylab missions. The M512 experiment facility was designed to support six in-space experiments intended to explore the advantages of manufacturing materials in the near-zero-gravity environment of Earth orbit. Detailed descriptions of the M512 facility and related experiment hardware are provided, with discussions of hardware verification and man-machine interfaces included. An analysis of the operation of the facility and experiments during the three Skylab missions is presented, including discussions of the hardware performance, anomalies, and data returned to earth.

  1. Development of the selective coagulation process. Final report

    SciTech Connect

    Yoon, R.H.; Luttrell, G.H.

    1992-07-01

    The selective hydrophobic coagulation (SHC) process is based on the recent finding that hydrophobic particles can be selectively coagulated without using traditional agglomerating agents or flocculants. The driving force for the coagulation is the attractive energy between hydrophobic surfaces, an interaction that has been overlooked in classical colloid chemistry. In most cases, selective separations can be achieved using simple pH control to disperse the mineral matter, followed by recovery of the coal coagula using techniques that take advantage of the size enlargement. In the present work, studies have been carried out to further investigate the fundamental mechanisms of the SHC process and the parameters that affect the process of separating coal from the ash-forming minerals and pyritic sulfur. Studies have included direct force measurements of the attractive interaction between model hydrophobic surfaces, in-situ measurements of the size distributions of coagula formed under a variety of operating conditions, and development of a population balance model to describe the coagulation process. An extended DLVO colloid stability model which includes a hydrophobic interaction energy term has also been developed to explain the findings obtained from the experimental studies. In addition to the fundamental studies, bench-scale process development test work has been performed to establish the best possible method of separating the coagula from dispersed mineral matter. Two types of separators, i.e., a sedimentation tank and a rotating drum screen, were examined in this study. The sedimentation tank proved to be the more efficient unit, achieving ash reductions as high as 60% in a single pass while recovering more than 90% of the combustible material. This device, which minimizes turbulence and coagula breakage, was used in subsequent test work to optimize design and operating parameters.

  2. Artificial Intelligence Based Selection of Optimal Cutting Tool and Process Parameters for Effective Turning and Milling Operations

    NASA Astrophysics Data System (ADS)

    Saranya, Kunaparaju; John Rozario Jegaraj, J.; Ramesh Kumar, Katta; Venkateshwara Rao, Ghanta

    2016-06-01

    With the increased trend in automation of modern manufacturing industry, the human intervention in routine, repetitive and data specific activities of manufacturing is greatly reduced. In this paper, an attempt has been made to reduce the human intervention in selection of optimal cutting tool and process parameters for metal cutting applications, using Artificial Intelligence techniques. Generally, the selection of appropriate cutting tool and parameters in metal cutting is carried out by experienced technician/cutting tool expert based on his knowledge base or extensive search from huge cutting tool database. The present proposed approach replaces the existing practice of physical search for tools from the databooks/tool catalogues with intelligent knowledge-based selection system. This system employs artificial intelligence based techniques such as artificial neural networks, fuzzy logic and genetic algorithm for decision making and optimization. This intelligence based optimal tool selection strategy is developed using Mathworks Matlab Version 7.11.0 and implemented. The cutting tool database was obtained from the tool catalogues of different tool manufacturers. This paper discusses in detail, the methodology and strategies employed for selection of appropriate cutting tool and optimization of process parameters based on multi-objective optimization criteria considering material removal rate, tool life and tool cost.

  3. Impact of processing parameters on the haemocompatibility of Bombyx mori silk films.

    PubMed

    Seib, F Philipp; Maitz, Manfred F; Hu, Xiao; Werner, Carsten; Kaplan, David L

    2012-02-01

    Silk has traditionally been used for surgical sutures due to its lasting strength and durability; however, the use of purified silk proteins as a scaffold material for vascular tissue engineering goes beyond traditional use and requires application-orientated biocompatibility testing. For this study, a library of Bombyx mori silk films was generated and exposed to various solvents and treatment conditions to reflect current silk processing techniques. The films, along with clinically relevant reference materials, were exposed to human whole blood to determine silk blood compatibility. All substrates showed an initial inflammatory response comparable to polylactide-co-glycolide (PLGA), and a low to moderate haemostasis response similar to polytetrafluoroethylene (PTFE) substrates. In particular, samples that were water annealed at 25 °C for 6 h demonstrated the best blood compatibility based on haemostasis parameters (e.g. platelet decay, thrombin-antithrombin complex, platelet factor 4, granulocytes-platelet conjugates) and inflammatory parameters (e.g. C3b, C5a, CD11b, surface-associated leukocytes). Multiple factors such as treatment temperature and solvent influenced the biological response, though no single physical parameter such as β-sheet content, isoelectric point or contact angle accurately predicted blood compatibility. These findings, when combined with prior in vivo data on silk, support a viable future for silk-based vascular grafts. PMID:22079005

  4. The influence of formulation and manufacturing process parameters on the characteristics of lyophilized orally disintegrating tablets.

    PubMed

    Jones, Rhys J; Rajabi-Siahboomi, Ali; Levina, Marina; Perrie, Yvonne; Mohammed, Afzal R

    2011-01-01

    Gelatin is a principal excipient used as a binder in the formulation of lyophilized orally disintegrating tablets. The current study focuses on exploiting the physicochemical properties of gelatin by varying formulation parameters to determine their influence on orally disintegrating tablet (ODT) characteristics. Process parameters, namely pH and ionic strength of the formulations, and ball milling were investigated to observe their effects on excipient characteristics and tablet formation. The properties and characteristics of the formulations and tablets which were investigated included: glass transition temperature, wettability, porosity, mechanical properties, disintegration time, morphology of the internal structure of the freeze-dried tablets, and drug dissolution. The results from the pH study revealed that adjusting the pH of the formulation away from the isoelectric point of gelatin, resulted in an improvement in tablet disintegration time possibly due to increase in gelatin swelling resulting in greater tablet porosity. The results from the ionic strength study revealed that the inclusion of sodium chloride influenced tablet porosity, tablet morphology and the glass transition temperature of the formulations. Data from the milling study showed that milling the excipients influenced formulation characteristics, namely wettability and powder porosity. The study concludes that alterations of simple parameters such as pH and salt concentration have a significant influence on formulation of ODT. PMID:24310589

  5. A summary report on the search for current technologies and developers to develop depth profiling/physical parameter end effectors

    SciTech Connect

    Nguyen, Q.H.

    1994-09-12

    This report documents the search strategies and results for available technologies and developers to develop tank waste depth profiling/physical parameter sensors. Sources searched include worldwide research reports, technical papers, journals, private industries, and work at Westinghouse Hanford Company (WHC) at Richland site. Tank waste physical parameters of interest are: abrasiveness, compressive strength, corrosiveness, density, pH, particle size/shape, porosity, radiation, settling velocity, shear strength, shear wave velocity, tensile strength, temperature, viscosity, and viscoelasticity. A list of related articles or sources for each physical parameters is provided.

  6. Process Development in the Teaching Laboratory

    NASA Astrophysics Data System (ADS)

    Klein, Leonard C.; Dana, Susanne M.

    1998-06-01

    Many experiences in high school and undergraduate laboratories are well-tested cookbook recipes that have already been designed to yield optimal results; the well-known synthesis of aspirin is such an example. In this project for advanced placement or second-year high school chemistry students, students mimic the process development in industrial laboratories by investigating the effect of varying conditions in the synthesis of aspirin. The class decides on criteria that should be explored (quantity of catalyst, temperature of reaction, etc.). The class is then divided into several teams with each team assigned a variable to study. Each team must submit a proposal describing how they will explore the variable before they start their study. After data on yield and purity has been gathered and evaluated, students discuss which method is most desirable, based on their agreed-upon criteria. This exercise provides an opportunity for students to review many topics from the course (rate of reaction, limiting reagents, Beer's Law) while participating in a cooperative exercise designed to imitate industrial process development.

  7. Developing cultural differences in face processing.

    PubMed

    Kelly, David J; Liu, Shaoying; Rodger, Helen; Miellet, Sébastien; Ge, Liezhong; Caldara, Roberto

    2011-09-01

    Perception and eye movements are affected by culture. Adults from Eastern societies (e.g. China) display a disposition to process information holistically, whereas individuals from Western societies (e.g. Britain) process information analytically. Recently, this pattern of cultural differences has been extended to face processing. Adults from Eastern cultures fixate centrally towards the nose when learning and recognizing faces, whereas adults from Western societies spread fixations across the eye and mouth regions. Although light has been shed on how adults can fixate different areas yet achieve comparable recognition accuracy, the reason why such divergent strategies exist is less certain. Although some argue that culture shapes strategies across development, little direct evidence exists to support this claim. Additionally, it has long been claimed that face recognition in early childhood is largely reliant upon external rather than internal face features, yet recent studies have challenged this theory. To address these issues, we tested children aged 7-12 years of age from the UK and China with an old/new face recognition paradigm while simultaneously recording their eye movements. Both populations displayed patterns of fixations that were consistent with adults from their respective cultural groups, which 'strengthened' across development as qualified by a pattern classifier analysis. Altogether, these observations suggest that cultural forces may indeed be responsible for shaping eye movements from early childhood. Furthermore, fixations made by both cultural groups almost exclusively landed on internal face regions, suggesting that these features, and not external features, are universally used to achieve face recognition in childhood. PMID:21884332

  8. Describing the catchment-averaged precipitation as a stochastic process improves parameter and input estimation

    NASA Astrophysics Data System (ADS)

    Del Giudice, Dario; Albert, Carlo; Rieckermann, Jörg; Reichert, Peter

    2016-04-01

    Rainfall input uncertainty is one of the major concerns in hydrological modeling. Unfortunately, during inference, input errors are usually neglected, which can lead to biased parameters and implausible predictions. Rainfall multipliers can reduce this problem but still fail when the observed input (precipitation) has a different temporal pattern from the true one or if the true nonzero input is not detected. In this study, we propose an improved input error model which is able to overcome these challenges and to assess and reduce input uncertainty. We formulate the average precipitation over the watershed as a stochastic input process (SIP) and, together with a model of the hydrosystem, include it in the likelihood function. During statistical inference, we use "noisy" input (rainfall) and output (runoff) data to learn about the "true" rainfall, model parameters, and runoff. We test the methodology with the rainfall-discharge dynamics of a small urban catchment. To assess its advantages, we compare SIP with simpler methods of describing uncertainty within statistical inference: (i) standard least squares (LS), (ii) bias description (BD), and (iii) rainfall multipliers (RM). We also compare two scenarios: accurate versus inaccurate forcing data. Results show that when inferring the input with SIP and using inaccurate forcing data, the whole-catchment precipitation can still be realistically estimated and thus physical parameters can be "protected" from the corrupting impact of input errors. While correcting the output rather than the input, BD inferred similarly unbiased parameters. This is not the case with LS and RM. During validation, SIP also delivers realistic uncertainty intervals for both rainfall and runoff. Thus, the technique presented is a significant step toward better quantifying input uncertainty in hydrological inference. As a next step, SIP will have to be combined with a technique addressing model structure uncertainty.

  9. Sensitivity study and parameter optimization of OCD tool for 14nm finFET process

    NASA Astrophysics Data System (ADS)

    Zhang, Zhensheng; Chen, Huiping; Cheng, Shiqiu; Zhan, Yunkun; Huang, Kun; Shi, Yaoming; Xu, Yiping

    2016-03-01

    Optical critical dimension (OCD) measurement has been widely demonstrated as an essential metrology method for monitoring advanced IC process in the technology node of 90 nm and beyond. However, the rapidly shrunk critical dimensions of the semiconductor devices and the increasing complexity of the manufacturing process bring more challenges to OCD. The measurement precision of OCD technology highly relies on the optical hardware configuration, spectral types, and inherently interactions between the incidence of light and various materials with various topological structures, therefore sensitivity analysis and parameter optimization are very critical in the OCD applications. This paper presents a method for seeking the optimum sensitive measurement configuration to enhance the metrology precision and reduce the noise impact to the greatest extent. In this work, the sensitivity of different types of spectra with a series of hardware configurations of incidence angles and azimuth angles were investigated. The optimum hardware measurement configuration and spectrum parameter can be identified. The FinFET structures in the technology node of 14 nm were constructed to validate the algorithm. This method provides guidance to estimate the measurement precision before measuring actual device features and will be beneficial for OCD hardware configuration.

  10. Statistical inference methods for recurrent event processes with shape and size parameters

    PubMed Central

    WANG, MEI-CHENG; HUANG, CHIUNG-YU

    2015-01-01

    Summary This paper proposes a unified framework to characterize the rate function of a recurrent event process through shape and size parameters. In contrast to the intensity function, which is the event occurrence rate conditional on the event history, the rate function is the occurrence rate unconditional on the event history, and thus it can be interpreted as a population-averaged count of events in unit time. In this paper, shape and size parameters are introduced and used to characterize the association between the rate function λ(·) and a random variable X. Measures of association between X and λ(·) are defined via shape- and size-based coefficients. Rate-independence of X and λ(·) is studied through tests of shape-independence and size-independence, where the shape-and size-based test statistics can be used separately or in combination. These tests can be applied when X is a covariable possibly correlated with the recurrent event process through λ(·) or, in the one-sample setting, when X is the censoring time at which the observation of N(·) is terminated. The proposed tests are shape- and size-based, so when a null hypothesis is rejected, the test results can serve to distinguish the source of violation. PMID:26412863

  11. Micropollutant biotransformation kinetics associate with WWTP process parameters and microbial community characteristics.

    PubMed

    Helbling, Damian E; Johnson, David R; Honti, Mark; Fenner, Kathrin

    2012-10-01

    The objective of this work was to identify relevant wastewater treatment plant (WWTP) parameters and underlying microbial processes that influence the biotransformation of a diverse set of micropollutants. To do this, we determined biotransformation rate constants for ten organic micropollutants in batch reactors seeded with activated sludge from ten diverse WWTPs. The estimated biotransformation rate constants for each compound ranged between one and four orders of magnitude among the ten WWTPs. The biotransformation rate constants were tested for statistical associations with various WWTP process parameters, amoA transcript abundance, and acetylene-inhibited monooxygenase activity. We determined that (i) ammonia removal associates with oxidative micropollutant biotransformation reaction rates; (ii) archaeal but not bacterial amoA transcripts associate with both ammonia removal and oxidative micropollutant biotransformation reaction rates; and (iii) the activity of acetylene-inhibited monooxygenases (including ammonia monooxygenase) associates with ammonia removal and the biotransformation rate of isoproturon, but does not associate with all oxidative micropollutant biotransformations. In combination, these results lead to the conclusion that ammonia removal and amoA transcript abundance can potentially be predictors of oxidative micropollutant biotransformation reactions, but that the biochemical mechanism is not necessarily linked to ammonia monooxygenase activity. PMID:22938719

  12. Milling Process FEM Simulation for Identification of Material Parameters Directly from Experiments

    NASA Astrophysics Data System (ADS)

    Maurel, A.; Fontaine, M.; Thibaud, S.; Michel, G.; Gelin, J. C.

    2007-05-01

    An identification procedure for the determination of material parameters that are used for the FEM simulation of milling processes is proposed. This procedure is based on the coupling of a numerical identification procedure and FEM simulations of milling operations. The experimental data result directly from measurements performed during milling experiments. A special device has been instrumented and calibrated to perform force and torque measurements, directly during machining experiments in using a piezoelectric dynamometer and a high frequency charge amplifier. The forces and torques are stored and low pass filtered if necessary, and these data provide the main basis for the identification procedure which is based on coupling 3D FEM simulations of milling and optimization/identification algorithms. The identification approach is mainly based on the Surfaces Response Method in the material parameters space, coupled to a sensitivity analysis. A Moving Least Square Approximation method is used to accelerate the identification process. The material behaviour is described from Johnson-Cook law. A fracture model is also added to consider chip formation and separation. The FEM simulations of milling are performed using explicit ALE based FEM code. The inverse identification method is here applied on a 304L stainless steel and the first results are presented.

  13. Milling Process FEM Simulation for Identification of Material Parameters Directly from Experiments

    SciTech Connect

    Maurel, A.; Fontaine, M.; Thibaud, S.; Michel, G.; Gelin, J. C.

    2007-05-17

    An identification procedure for the determination of material parameters that are used for the FEM simulation of milling processes is proposed. This procedure is based on the coupling of a numerical identification procedure and FEM simulations of milling operations. The experimental data result directly from measurements performed during milling experiments. A special device has been instrumented and calibrated to perform force and torque measurements, directly during machining experiments in using a piezoelectric dynamometer and a high frequency charge amplifier. The forces and torques are stored and low pass filtered if necessary, and these data provide the main basis for the identification procedure which is based on coupling 3D FEM simulations of milling and optimization/identification algorithms. The identification approach is mainly based on the Surfaces Response Method in the material parameters space, coupled to a sensitivity analysis. A Moving Least Square Approximation method is used to accelerate the identification process. The material behaviour is described from Johnson-Cook law. A fracture model is also added to consider chip formation and separation. The FEM simulations of milling are performed using explicit ALE based FEM code. The inverse identification method is here applied on a 304L stainless steel and the first results are presented.

  14. Data processing in subspace identification and modal parameter identification of an arch bridge

    NASA Astrophysics Data System (ADS)

    Fan, Jiangling; Zhang, Zhiyi; Hua, Hongxing

    2007-05-01

    A data-processing method concerning subspace identification is presented to improve the identification of modal parameters from measured response data only. The identification procedure of this method consists of two phases, first estimating frequencies and damping ratios and then extracting mode shapes. Elements of Hankel matrices are specially rearranged to enhance the identifiability of weak characteristics and the robustness to noise contamination. Furthermore, an alternative stabilisation diagram in combination with component energy index is adopted to effectively separate spurious and physical modes. On the basis of identified frequencies, mode shapes are extracted from the signals obtained by filtering measured data with a series of band-pass filters. The proposed method was tested with a concrete-filled steel tubular arch bridge, which was subjected to ambient excitation. Gabor representation was also employed to process measured signals before conducting parameter identification. Identified results show that the proposed method can give a reliable separation of spurious and physical modes as well as accurate estimates of weak modes only from response signals.

  15. Optimization of processing parameters for the preparation of phytosterol microemulsions by the solvent displacement method.

    PubMed

    Leong, Wai Fun; Che Man, Yaakob B; Lai, Oi Ming; Long, Kamariah; Misran, Misni; Tan, Chin Ping

    2009-09-23

    The purpose of this study was to optimize the parameters involved in the production of water-soluble phytosterol microemulsions for use in the food industry. In this study, response surface methodology (RSM) was employed to model and optimize four of the processing parameters, namely, the number of cycles of high-pressure homogenization (1-9 cycles), the pressure used for high-pressure homogenization (100-500 bar), the evaporation temperature (30-70 degrees C), and the concentration ratio of microemulsions (1-5). All responses-particle size (PS), polydispersity index (PDI), and percent ethanol residual (%ER)-were well fit by a reduced cubic model obtained by multiple regression after manual elimination. The coefficient of determination (R(2)) and absolute average deviation (AAD) value for PS, PDI, and %ER were 0.9628 and 0.5398%, 0.9953 and 0.7077%, and 0.9989 and 1.0457%, respectively. The optimized processing parameters were 4.88 (approximately 5) homogenization cycles, homogenization pressure of 400 bar, evaporation temperature of 44.5 degrees C, and concentration ratio of microemulsions of 2.34 cycles (approximately 2 cycles) of high-pressure homogenization. The corresponding responses for the optimized preparation condition were a minimal particle size of 328 nm, minimal polydispersity index of 0.159, and <0.1% of ethanol residual. The chi-square test verified the model, whereby the experimental values of PS, PDI, and %ER agreed with the predicted values at a 0.05 level of significance. PMID:19694442

  16. The role of interior watershed processes in improving parameter estimation and performance of watershed models.

    PubMed

    Yen, Haw; Bailey, Ryan T; Arabi, Mazdak; Ahmadi, Mehdi; White, Michael J; Arnold, Jeffrey G

    2014-09-01

    Watershed models typically are evaluated solely through comparison of in-stream water and nutrient fluxes with measured data using established performance criteria, whereas processes and responses within the interior of the watershed that govern these global fluxes often are neglected. Due to the large number of parameters at the disposal of these models, circumstances may arise in which excellent global results are achieved using inaccurate magnitudes of these "intra-watershed" responses. When used for scenario analysis, a given model hence may inaccurately predict the global, in-stream effect of implementing land-use practices at the interior of the watershed. In this study, data regarding internal watershed behavior are used to constrain parameter estimation to maintain realistic intra-watershed responses while also matching available in-stream monitoring data. The methodology is demonstrated for the Eagle Creek Watershed in central Indiana. Streamflow and nitrate (NO) loading are used as global in-stream comparisons, with two process responses, the annual mass of denitrification and the ratio of NO losses from subsurface and surface flow, used to constrain parameter estimation. Results show that imposing these constraints not only yields realistic internal watershed behavior but also provides good in-stream comparisons. Results further demonstrate that in the absence of incorporating intra-watershed constraints, evaluation of nutrient abatement strategies could be misleading, even though typical performance criteria are satisfied. Incorporating intra-watershed responses yields a watershed model that more accurately represents the observed behavior of the system and hence a tool that can be used with confidence in scenario evaluation. PMID:25603246

  17. Development of a Gas-Promoted Oil Agglomeration Process

    SciTech Connect

    C. Nelson; F. Zhang; J. Drzymala; M. Shen; R. Abbott; T. D. Wheelock

    1997-11-01

    The preliminary laboratory-scale development of a gas-promoted, oil agglomeration process for cleaning coal was carried out with scale model mixing systems in which aqueous suspensions of ultrafine coal particles were treated with a liquid hydrocarbon and a small amount of air. The resulting agglomerates were recovered by screening. During a batch agglomeration test the progress of agglomeration was monitored by observing changes in agitator torque in the case of concentrated suspensions or by observing changes in turbidity in the case of dilute suspensions. Dilute suspensions were employed for investigating the kinetics of agglomeration, whereas concentrated suspensions were used for determining parameters that characterize the process of agglomeration. A key parameter turned out to be the minimum time te required to produce compact spherical agglomerates. Other important parameters included the projected area mean particle diameter of the agglomerates recovered at the end of a test as well as the ash content and yield of agglomerates. Batch agglomeration tests were conducted with geometrically similar mixing tanks which ranged in volume from 0.346 to 11.07 liters. Each tank was enclosed to control the amount of air present. A variable speed agitator fitted with a six blade turbine impeller was used for agitation. Tests were conducted with moderately hydrophobic Pittsburgh No. 8 coal and with more hydrophobic Upper Freeport coal using either n-heptane, i-octane, or hexadecane as an agglomerant.

  18. Real-time digital processing of Doppler ultrasound signals and calculation of flow parameters.

    PubMed

    Schlindwein, F S; Vieira, M H; Vasconcelos, C F; Simpson, D M

    1994-01-01

    Vascular diseases and their complications are responsible for around 27% of deaths in Brazil. Doppler ultrasound is a non-invasive technique that has been used to study blood flow in intact blood vessels since Satomura first reported the potential of the technique in 1959. Because it is non-invasive it makes sequential studies and those in normals feasible. Whereas in contrast angiography only vessel anatomy is displayed, Doppler ultrasound produces dynamic information on blood-flow. It may be used to estimate flow-rates, to image regions of blood flow (colour Doppler), and to help in locating sites of arterial disease, thus complementing X-ray examinations. This paper describes a system based on a Digital Signal Processor for real-time spectrum analysis of Doppler ultrasound signals, real-time display of sonograms, and calculation and analysis of three parameters of clinical interest derived from the Doppler signal. The system comprises a TMS320C25 development board, which acquires the signal and performs spectrum analysis, and a microcomputer, which reads the spectral estimates, displays them as a sonogram in real-time and calculates a set of spectral parameters proposed in the literature. The system permits a maximum sampling frequency of 40.96 kHz, and in the sonogram, 80 power spectra per second (each with 128 frequency bins) are displayed. In a preliminary study, the stability of the haemodynamic parameters and their dependence on a user-defined threshold value is investigated. PMID:7968870

  19. Influence of process parameters on properties of Nanostructured Lipid Carriers (NLC) formulation.

    PubMed

    Lasoń, Elwira; Sikora, Elżbieta; Ogonowski, Jan

    2013-01-01

    Nanostructured lipid carriers (NLC) are stable colloidal formulations with notable advantages for drug delivery systems. Thanks to their physicochemical stability, biocompatibility, biodegradability and controlled drug release, they have received increasing attention for the last several years. The aim of the study was to prepare and characterize nanostructured lipid carriers (NLC). Both, the effect of the process parameters and the effect of the preemulsion composition on the NLC properties were investigated. In the work, different type of surfactants (i.e. decyl glucoside, Poloxamer188, Tween 80, sodium cholate) and their combinations were used to stabilize NLC dispersions. Moreover, several kinds of solid lipids (modified beeswax, gliceryl behenate, cetyl palmitate and berry wax) and liquid lipids (caprilic/capric triglyceride and decyl oleate) were applied. An ultrasonication method using a probe type sonicator was used to obtain NLC, and the time and energy of the process were modified throuhout. The physicochemical properties of the formulations, such as particle size, size distribution, polidispersity index were studied using the dynamic light scattering (DLS) method. The electrophoretic mobility of obtained particles was also measured, using the Zetasizer Nano ZS Malvern Instrument based on the Laser Doppler Velocimetry (LDV) technique. Knowing the value of electrophoretic mobility of particles for given conditions, the zeta potential was determined. The obtained results showed that the process parameters and the composition of the preemulsion had significant impact on the nanoparticles structure. The optimal formulations size ranged between 60 and 80 nm, and the value of their zeta potential was up to -30mV. The stability of these systems was further confirmed by macroscopic observation. PMID:24432330

  20. The effect of process parameters on the Liquid Flame Spray generated titania nanoparticles.

    PubMed

    Aromaa, Mikko; Keskinen, Helmi; Mäkelä, Jyrki M

    2007-11-01

    Nanoparticles have become important in many applications. It is essential to be able to control the particle size because the properties of nanoparticles change dramatically with particle size. An efficient way to generate nanoparticles is via aerosol processes. In this study we used Liquid Flame Spray consisting of liquid precursor droplets sprayed into a high-speed hydrogen/oxygen flame where they evaporate, vapours react and nucleate to form titania nanoparticles. Using flame methods, also dopants and sensitizers can easily be introduced in order to, e.g. improve the photocatalytic activity of the nanomaterial. To obtain a practical guideline in order to tailor the final nanoparticle size in the process, we have systematically studied the effects of different process parameters on the particle size of titania. Titania is used, e.g. as a photocatalyst, and then both particle size and crystal structure are important when looking at the efficiency. In this work, the generated nanoparticle size has been measured by aerosol instrumentation and the particle morphology has been verified with transmission electron microscopy. In Liquid Flame Spray method, there are several adjustable parameters such as precursor feed rate into the flame; concentration of the precursor; precursor material itself as well as solvent used in the precursor; mass flow of combustion gases and also the mechanical design of the torch used. We used metal organic based titanium precursors in alcohol solvents, predominantly ethanol and 2-propanol. Large differences in particle production between the precursors were found. Differences could also be seen for various solvents. As for precursor feed in the flame, the more mass is introduced the larger the nanoparticles are, i.e. precursor concentration and precursor feed rate have an impact on particle size. A similar phenomenon can be discovered for the combustion gas flow rates. Torch design also plays an important role in controlling the particle

  1. The effect of selected parameters of the honing process on cylinder liner surface topography

    NASA Astrophysics Data System (ADS)

    Pawlus, P.; Dzierwa, A.; Michalski, J.; Reizer, R.; Wieczorowski, M.; Majchrowski, R.

    2014-04-01

    Many truck cylinder liners made from gray cast iron were machined. Ceramic and diamond honing stones were used in the last stages of operation: coarse honing and plateau honing. The effect of honing parameters on the cylinder liner surface topography was studied. Selected surface topography parameters were response variables. It was found that parameters from the Sq group were sensitive to honing parameter change. When plateau honing time varied, the Smq parameter increased, while the other parameters, Spq and Svq, were stable.

  2. Motion compensated image processing and optimal parameters for egg crack detection using modified pressure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shell eggs with microcracks are often undetected during egg grading processes. In the past, a modified pressure imaging system was developed to detect eggs with microcracks without adversely affecting the quality of normal intact eggs. The basic idea of the modified pressure imaging system was to ap...

  3. Development of the SOFIA Image Processing Tool

    NASA Technical Reports Server (NTRS)

    Adams, Alexander N.

    2011-01-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a Boeing 747SP carrying a 2.5 meter infrared telescope capable of operating between at altitudes of between twelve and fourteen kilometers, which is above more than 99 percent of the water vapor in the atmosphere. The ability to make observations above most water vapor coupled with the ability to make observations from anywhere, anytime, make SOFIA one of the world s premiere infrared observatories. SOFIA uses three visible light CCD imagers to assist in pointing the telescope. The data from these imagers is stored in archive files as is housekeeping data, which contains information such as boresight and area of interest locations. A tool that could both extract and process data from the archive files was developed.

  4. Developing processing techniques for Skylab data

    NASA Technical Reports Server (NTRS)

    Nalepka, R. F. (Principal Investigator); Malila, W. A.; Morgenstern, J. P.

    1975-01-01

    The author has identified the following significant results. The effects of misregistration and the scan-line-straightening algorithm on multispectral data were found to be: (1) there is greatly increased misregistration in scan-line-straightening data over conic data; (2) scanner caused misregistration between any pairs of channels may not be corrected for in scan-line-straightened data; and (3) this data will have few pure field center pixels than will conic data. A program SIMSIG was developed implementing the signature simulation model. Data processing stages of the experiment were carried out, and an analysis was made of the effects of spatial misregistration on field center classification accuracy. Fifteen signatures originally used for classifying the data were analyzed, showing the following breakdown: corn (4 signatures), trees (2), brush (1), grasses, weeds, etc. (5), bare soil (1), soybeans (1), and alfalfa (1).

  5. Socioeconomic Status, Family Processes, and Individual Development

    PubMed Central

    Conger, Rand D.; Conger, Katherine J.; Martin, Monica J.

    2010-01-01

    Research during the past decade shows that social class or socioeconomic status (SES) is related to satisfaction and stability in romantic unions, the quality of parent-child relationships, and a range of developmental outcomes for adults and children. This review focuses on evidence regarding potential mechanisms proposed to account for these associations. Research findings reported during the past decade demonstrate support for an interactionist model of the relationship between SES and family life, which incorporates assumptions from both the social causation and social selection perspectives. The review concludes with recommendations for future research on SES, family processes and individual development in terms of important theoretical and methodological issues yet to be addressed. PMID:20676350

  6. Development of the LICADO coal cleaning process

    SciTech Connect

    Not Available

    1990-07-31

    Development of the liquid carbon dioxide process for the cleaning of coal was performed in batch, variable volume (semi-continuous), and continuous tests. Continuous operation at feed rates up to 4.5 kg/hr (10-lb/hr) was achieved with the Continuous System. Coals tested included Upper Freeport, Pittsburgh, Illinois No. 6, and Middle Kittanning seams. Results showed that the ash and pyrite rejections agreed closely with washability data for each coal at the particle size tested (-200 mesh). A 0.91 metric ton (1-ton) per hour Proof-of-Concept Plant was conceptually designed. A 181 metric ton (200 ton) per hour and a 45 metric ton (50 ton) per hour plant were sized sufficiently to estimate costs for economic analyses. The processing costs for the 181 metric ton (200 ton) per hour and 45 metric ton (50 ton) per hour were estimated to be $18.96 per metric ton ($17.20 per ton) and $11.47 per metric ton ($10.40 per ton), respectively for these size plants. The costs for the 45 metric ton per hour plant are lower because it is assumed to be a fines recovery plant which does not require a grinding circuit of complex waste handling system.

  7. Developing hypertension guidelines: an evolving process.

    PubMed

    Kotchen, Theodore A

    2014-06-01

    Hypertension guidelines provide up-to-date information and recommendations for hypertension management to healthcare providers, and they facilitate translation of new knowledge into clinical practice. Guidelines represent consensus statements by expert panels, and the process of guideline development has inherent vulnerabilities. Between 1977 and 2003, under the direction of the National Institutes of Health (NIH), the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC) issued 7 reports. The evolution of the JNC recommendations reflects the acquisition of observational and clinical trial data and the availability of newer antihypertensive drugs. Despite 5 years in preparation, NIH did not release a JNC 8 report and recently made the decision to withdraw from issuing guidelines. The responsibility for issuing hypertension-related guidelines was transferred to the American Heart Association (AHA) and the American College of Cardiology. Without the endorsement of the NIH or the AHA, JNC 8 committee members recently published their guideline report. Notably, there have been discrepancies of JNC recommendations over time as well as discrepancies with recommendations of other professional organizations. The Institute of Medicine recently recommended criteria for "trustworthy" guidelines. Criticisms of the guideline process, and of the guidelines themselves, should not obscure their likely contribution to improved hypertension control and to decreases of mortality rates of stroke and cardiovascular disease over the past several decades. Nevertheless, translation of guidelines into clinical practice remains a challenge. PMID:24572703

  8. The development of a PM3 parameter set to describe iron-sulfur proteins

    NASA Astrophysics Data System (ADS)

    Sundararajan, Mahesh; McNamara, Jonathan P.; Hillier, Ian H.; Wang, Hong; Burton, Neil A.

    2005-03-01

    A PM3 parameter set for iron has been developed, which is appropriate for the active site of iron sulfur proteins having a single iron atom by fitting DFT data obtained for a redox site analogue. These parameters are then tested on a set of such analogues involving a variety of ligands, and show good agreement with both DFT and experimental data for these species. The use of these parameters within a two level ONIOM treatment of the protein rubredoxin, yields accurate predictions of the effect of the enzyme on both Fe-S bond lengths and inner sphere reorganization energies.

  9. Development of explicit diffraction corrections for absolute measurements of acoustic nonlinearity parameters in the quasilinear regime.

    PubMed

    Jeong, Hyunjo; Zhang, Shuzeng; Cho, Sungjong; Li, Xiongbing

    2016-08-01

    In absolute measurements of acoustic nonlinearity parameters, amplitudes of harmonics must be corrected for diffraction effects. In this study, we develop explicit multi-Gaussian beam (MGB) model-based diffraction corrections for the first three harmonics in weakly nonlinear, axisymmetric sound beams. The effects of making diffraction corrections on nonlinearity parameter estimation are investigated by defining "total diffraction correction (TDC)". The results demonstrate that TDC cannot be neglected even for harmonic generation experiments in the nearfield region. PMID:27186964

  10. Optimising Drug Solubilisation in Amorphous Polymer Dispersions: Rational Selection of Hot-melt Extrusion Processing Parameters.

    PubMed

    Li, Shu; Tian, Yiwei; Jones, David S; Andrews, Gavin P

    2016-02-01

    The aim of this article was to construct a T-ϕ phase diagram for a model drug (FD) and amorphous polymer (Eudragit® EPO) and to use this information to understand the impact of how temperature-composition coordinates influenced the final properties of the extrudate. Defining process boundaries and understanding drug solubility in polymeric carriers is of utmost importance and will help in the successful manufacture of new delivery platforms for BCS class II drugs. Physically mixed felodipine (FD)-Eudragit(®) EPO (EPO) binary mixtures with pre-determined weight fractions were analysed using DSC to measure the endset of melting and glass transition temperature. Extrudates of 10 wt% FD-EPO were processed using temperatures (110°C, 126°C, 140°C and 150°C) selected from the temperature-composition (T-ϕ) phase diagrams and processing screw speed of 20, 100 and 200rpm. Extrudates were characterised using powder X-ray diffraction (PXRD), optical, polarised light and Raman microscopy. To ensure formation of a binary amorphous drug dispersion (ADD) at a specific composition, HME processing temperatures should at least be equal to, or exceed, the corresponding temperature value on the liquid-solid curve in a F-H T-ϕ phase diagram. If extruded between the spinodal and liquid-solid curve, the lack of thermodynamic forces to attain complete drug amorphisation may be compensated for through the use of an increased screw speed. Constructing F-H T-ϕ phase diagrams are valuable not only in the understanding drug-polymer miscibility behaviour but also in rationalising the selection of important processing parameters for HME to ensure miscibility of drug and polymer. PMID:26729536

  11. Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

    PubMed

    Loaiza, Vanessa M; Camos, Valérie

    2016-01-01

    The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects. PMID:27152126

  12. Optimizing the equal channel angular pressing process (ECAP) operation parameters to produce bulk nanostructure materials

    SciTech Connect

    Abushgair, K.

    2015-03-30

    In this work we were interested in doing simulation using finite elements analysis (FEA) to study the equal channel angular pressing process (ECAP), which is currently one of the most popular methods of severe plastic deformation Processes (SPD). for fabricating Ultra-Fine Grained (UFG) materials, because it allows very high strains to be imposed leading to extreme work hardening and microstructural refinement. The main object of this study is to establish the influence of main parameters which effect ECAP process which are magnitude of the die angle and the friction coefficient. The angle studied between (90-135°) degree, and magnitude of the friction coefficient μ between (0.12-0.6), and number of pass. The samples were made from aluminum alloy at room temperature with (15X 15) mm cross section and 150 mm length. The simulation result shows that normal elastic strain, shears elastic strain, and max. shear elastic strain increased, when changing the angle from 90° to 100°. and decrease between the angle 110° to 135°. Also the total deformation increased when we change die angle from 90° to 135°. By studding the friction effect on the die and sample we noted that increasing the friction coefficient from 0.12 to 0.6, normal elastic strain, and shear elastic strain increased and increasing the friction coefficient from 0.1 to 0.6 decrease the normal and shear stress.

  13. Image processing analysis of nuclear track parameters for CR-39 detector irradiated by thermal neutron

    NASA Astrophysics Data System (ADS)

    Al-Jobouri, Hussain A.; Rajab, Mustafa Y.

    2016-03-01

    CR-39 detector which covered with boric acid (H3Bo3) pellet was irradiated by thermal neutrons from (241Am - 9Be) source with activity 12Ci and neutron flux 105 n. cm-2. s-1. The irradiation times -TD for detector were 4h, 8h, 16h and 24h. Chemical etching solution for detector was sodium hydroxide NaOH, 6.25N with 45 min etching time and 60 C˚ temperature. Images of CR-39 detector after chemical etching were taken from digital camera which connected from optical microscope. MATLAB software version 7.0 was used to image processing. The outputs of image processing of MATLAB software were analyzed and found the following relationships: (a) The irradiation time -TD has behavior linear relationships with following nuclear track parameters: i) total track number - NT ii) maximum track number - MRD (relative to track diameter - DT) at response region range 2.5 µm to 4 µm iii) maximum track number - MD (without depending on track diameter - DT). (b) The irradiation time -TD has behavior logarithmic relationship with maximum track number - MA (without depending on track area - AT). The image processing technique principally track diameter - DT can be take into account to classification of α-particle emitters, In addition to the contribution of these technique in preparation of nano- filters and nano-membrane in nanotechnology fields.

  14. Enzymatic Production of Bioxylitol from Sawdust Hydrolysate: Screening of Process Parameters.

    PubMed

    Rafiqul, I S M; Sakinah, A M M; Zularisam, A W

    2015-06-01

    Xylose-rich sawdust hydrolysate can be an economic substrate for the enzymatic production of xylitol, a specialty product. It is important to identify the process factors influencing xylitol production. This research aimed to screen the parameters significantly affecting bioxylitol synthesis from wood sawdust by xylose reductase (XR). Enzymatic bioxylitol production was conducted to estimate the effect of different variables reaction time (2-18 h), temperature (20-70 °C), pH (4.0-9.0), NADPH (1.17-5.32 g/L), and enzyme concentration (2-6 %) on the yield of xylitol. Fractional factorial design was followed to identify the key process factors. The screening design identified that time, temperature, and pH are the most significant factors influencing bioxylitol production among the variables with the values of 12 h, 35 °C, and 7.0, respectively. These conditions led to a xylitol yield of 71 % (w/w). This is the first report on the statistical screening of process variables influencing enzyme-based bioxylitol production from lignocellulosic biomass. PMID:25904039

  15. Functional relationships for the estimation of van Genuchten parameter values in landfill processes models.

    PubMed

    White, Jim; Zardava, Kiriaki; Nayagum, Dharumarajen; Powrie, William

    2015-04-01

    Numerical models of landfill processes need to be able to estimate the capillary pressure and relative permeability of waste as a function of moisture content using analytical equations such as the van Genuchten equations. The paper identifies the range of van Genuchten parameter values for use in models and proposes a formulaic relationship between these parameter values and saturated moisture content. The concept of porous material, its behaviour under unsaturated conditions and Mualem's integral transform equation that estimates relative permeability from capillary pressure are reviewed. The application of the algebraic form of the capillary pressure function proposed by van Genuchten and its application using Mualem's transform to obtain the van Genuchten algebraic functions for relative permeability are discussed. Functional relationships are identified between saturated moisture content and the van Genuchten parameters using a database of results from other sources. These relationships may be used in numerical modelling of unsaturated flow in landfilled waste where the saturated moisture content varies significantly as the result of compression, settlement and degradation. A 2D numerical model simulation of leachate recirculation is used to investigate the sensitivity of the simulation to the introduction of these functional relationships. It is found that the transient liquid and gas flows across the model boundaries appear to be insensitive to whether or not the functions are incorporated into the model algorithm. However it is observed that using the relationships does have some impact on the distribution of the degree of saturation throughout the model and on the transient behaviour of the way in which the recirculation recharges the waste. However it is not thought that this impact would be sufficient to influence the design of a leachate recirculation system. PMID:25573738

  16. Scalable Hyper-parameter Estimation for Gaussian Process Based Time Series Analysis

    SciTech Connect

    Chandola, Varun; Vatsavai, Raju

    2010-01-01

    Gaussian process (GP) is increasingly becoming popular as a kernel machine learning tool for non-parametric data analysis. Recently, GP has been applied to model non-linear dependencies in time series data. GP based analysis can be used to solve problems of time series prediction, forecasting, missing data imputation, change point detection, anomaly detection, etc. But the use of GP to handle massive scientific time series data sets has been limited, owing to its expensive computational complexity. The primary bottleneck is the handling of the covariance matrix whose size is quadratic in the length of the time series. In this paper we propose a scalable method that exploit the special structure of the covariance matrix for hyper-parameter estimation in GP based learning. The proposed method allows estimation of hyper parameters associated with GP in quadratic time, which is an order of magnitude improvement over standard methods with cubic complexity. Moreover, the proposed method does not require explicit computation of the covariance matrix and hence has memory requirement linear to the length of the time series as opposed to the quadratic memory requirement of standard methods. To further improve the computational complexity of the proposed method, we provide a parallel version to concurrently estimate the log likelihood for a set of time series which is the key step in the hyper-parameter estimation. Performance results on a multi-core system show that our proposed method provides significant speedups as high as 1000, even when running in serial mode, while maintaining a small memory footprint. The parallel version exploits the natural parallelization potential of the serial algorithm and is shown to perform significantly better than the serial faster algorithm, with speedups as high as 10.

  17. Technology Transfer and the Product Development Process

    SciTech Connect

    Mock, John E.

    1989-03-21

    It is my pleasure this morning to address a topic that is much talked about in passing but rarely examined from a first person point of view. That topic is Technology Transfer. Over the next 30 minutes I'd like to approach Technology Transfer within the context of the Product Development Process looking at it from the perspectives of the federal government researcher and the industry manufacturer/user. Fist let us recognize that we are living in an ''Information Age'', where global economic and military competition is determined as much by technology as it is by natural resource assets. It is estimated that technical/scientific information is presently growing at a rate of l3 percent per year; this is expected to increase to 30 percent per year by the turn of the century. In fact, something like 90 percent of all scientific knowledge has been generated in the last 30 years; this pool will double again in the next 10-15 years (Exhibit 1). Of all the scientists and engineers throughout history, 90% live and work in the present time. Successfully managing this technical information/knowledge--i.e., transforming the results of R&D to practical applications--will be an important measure of national strength. A little over a dozen years ago, the United States with only 5 percent of the world's population was generating approximately 75 percent of the world's technology. The US. share is now 50 percent and may decline to 30 percent by the turn of the century. This decline won't be because of downturn in U.S. technological advances but because the other 95 percent of the world's population will be increasing its contribution. Economic and military strength then, will be determined by how quickly and successfully companies, industries, and nations can apply new technological information to practical applications--i.e., how they manage technology transfer within the context of the product development process. Much discussion and pronouncements are ongoing in public forums

  18. Same catchment, different models, same dominant processes? - How temporal patterns of dominant parameters vary between two hydrological models

    NASA Astrophysics Data System (ADS)

    Guse, Björn; Pechlivanidis, Ilias; Pfannerstill, Matthias; Donnelly, Chantal; Arheimer, Berit; Fohrer, Nicola

    2016-04-01

    Dominant hydrological processes change during the year. The variations in the dominance of modelled processes also lead to changes in the sensitivity of model parameters over time. An analysis of the temporal dynamics in parameter sensitivity (TEDPAS) provides daily sensitivity values for each model parameter. Thus, TEDPAS shows seasonal patterns of model parameter sensitivities and the seasonality of the corresponding processes. Each hydrological model consists of model-specific structures and parameters. Depending on differences in the model concepts, the parameters are partly similar or can be partly difficult to compare. Thus, the application of TEDPAS to different models is expected to lead to different seasonal patterns of dominant model parameters. However, in a world of perfect models, seasonal patterns of the corresponding dominant processes of the same catchment should be identical in different models. To investigate this, TEDPAS is applied on the hydrological models SWAT (Soil and Water Assessment Tool) and HYPE (Hydrological Predictions for the Environment) for the Treene catchment in Northern Germany. By comparing daily sensitivities of parameters between both models, similarities and differences in the seasonal patterns of parameter dominance are detected. These results are analyzed and explained in relation to differences in the model structure of SWAT and HYPE. The comparison of SWAT and HYPE shows differences in the seasonal variations in dominant parameters and corresponding processes. Similar patterns of dominant processes in both models provide more confidence on the model structures. In contrast, differences in these patterns give insights which model components need to be reconsidered for an appropriate use in the study catchment. Based on the TEDPAS analysis it could be clearly derived which process needs to be investigated more detailed. This study contributes thus to improved hydrological consistency during model construction and a better

  19. Assessment of PEM4PIT parameters by analyzing catchment form and processes

    NASA Astrophysics Data System (ADS)

    Santini, M.; Grimaldi, S.; Nardi, F.; Petroselli, A.

    2008-12-01

    A physically based approach (PEM4PIT, Physical Erosion Model for PIT removal) was recently introduced to correct hydrologic spurious depressions (pits) and flat areas in Digital Elevation Models. Despite PEM4PIT proved to be more suitable than commonly used geometric methods to reconstruct hydrologically connected topography and reliable stream network metrics, fundamental in rainfall/runoff modeling, the best choice of the three model parameters (slope-area exponent, (theta) erodibility (beta), and diffusivity (D)) remained an open issue to be investigated. In this work a methodology to select the optimal set of parameters is described. In particular two methods are illustrated for theta estimation, the former using Horton ratios (Flint, 1974) and the latter analyzing the "approximate characteristic form" of slope profile (Kirkby, 1971). Regarding beta and D, they are estimated applying separately a simplified topographic equilibrium equation for the basin domains interested by the fluvial erosion and diffusion processes, respectively. ASTER DEMs of several case studies watersheds are used as input dataset; finally PEM4PIT results are compared, in terms of extracted network, with the results of standard approaches and with the digitized bluelines.

  20. Evaluating the impact of cell culture process parameters on monoclonal antibody N-glycosylation.

    PubMed

    Ivarsson, Marija; Villiger, Thomas K; Morbidelli, Massimo; Soos, Miroslav

    2014-10-20

    Bioreactor process parameters influence the N-linked glycosylation profile of the produced monoclonal antibodies. A systematic assessment of their impact is a prerequisite for providing controllability over glycosylation, one of the most critical quality attributes of therapeutic antibodies. In this study we investigated the effect of single and combined chemical and mechanical stress parameters on the glycan microheterogeneity of an IgG1 antibody using a shift-experiment procedure in batch cultures. The N-linked glycosylation profile of the murine IgG1 was found to be highly complex since it included terminal galactosylation and sialylation, as well as variable core-fucosylation. Within a pH range of 6.8 to 7.8 differences in galactosylation and sialylation of approximately 50% were obtained. Variation of dissolved oxygen tension (10-90% air saturation) resulted in a maximum variability of 20% in galactosylation and 30% in sialylation. In contrast, no significant effect on the glycosylation profile was observed when osmolarity increased from 320 to 420 mOsm/kg and sparging from 0.05 to 0.2 vvm. In this study a better understanding of bioprocess-related factors affecting critical quality attributes under the scope of QbD is provided and can bring us one step closer towards desired and targeted glycosylation for future therapeutic proteins. PMID:25173615

  1. Surface functionalization of nanofibrillated cellulose extracted from wheat straw: Effect of process parameters.

    PubMed

    Singh, Mandeep; Kaushik, Anupama; Ahuja, Dheeraj

    2016-10-01

    Aggregates of microfibrillated cellulose isolated from wheat straw fibers were subjected to propionylation under different processing conditions of time, temperature and concentration. The treated fibers were then homogenized to obtain surface modified nanofibrillated cellulose. For varying parameters, progress of propionylation and its effects on various characteristics was investigated by FTIR, degree of substitution, elemental analysis, SEM, EDX, TEM, X-ray diffraction, static and dynamic contact angle measurements. Thermal stability of the nanofibrils was also investigated using thermogravimetric technique. FTIR analysis confirmed the propionylation of the hydroxyl groups of the cellulose fibers. The variations in reaction conditions such as time and temperature had shown considerable effect on degree of substitution (DS) and surface contact angle (CA). These characterization results represent the optimizing conditions under which cellulose nanofibrils with hydrophobic characteristics up to contact angle of 120° can be obtained. PMID:27312612

  2. Influence of Processing Parameters on Grain Size Evolution of a Forged Superalloy

    NASA Astrophysics Data System (ADS)

    Reyes, L. A.; Páramo, P.; Salas Zamarripa, A.; de la Garza, M.; Guerrero-Mata, M. P.

    2016-01-01

    The microstructure evolution of nickel-based superalloys has a great influence on the mechanical behavior during service conditions. Microstructure modification and the effect of process variables such as forging temperature, die-speed, and tool heating were evaluated after hot die forging of a heat-resistant nickel-based alloy. Forging sequences in a temperature range from 1253 to 1323 K were considered through experimental trials. An Avrami model was applied using finite element data to evaluate the average grain size and recrystallization at different evolution zones. It was observed that sequential forging at final temperatures below 1273 K provided greater grain refinement through time-dependent recrystallization phenomena. This investigation was aim to explore the influence of forging parameters on grain size evolution in order to design a fully homogenous and refined microstructure after hot die forging.

  3. The effect of processing parameters on plasma sprayed beryllium for fusion applications

    SciTech Connect

    Castro, R.G.; Stanek, P.W.; Jacobson, L.A.; Cowgill, D.F.; Snead, L.L.

    1993-10-01

    Plasma spraying is being investigated as a potential coating technique for applying thin (0.1--5mm) layers of beryllium on plasma facing surfaces of blanket modules in ITER and also as an in-situ repair technique for repairing eroded beryllium surfaces in high heat flux divertor regions. High density spray deposits (>98% of theoretical density) of beryllium will be required in order to maximize the thermal conductivity of the beryllium coatings. A preliminary investigation was done to determine the effect of various processing parameters (particle size, particle morphology, secondary gas additions and reduced chamber pressure) on the as-deposited density of beryllium. The deposits were made using spherical beryllium feedstock powder which was produced by centrifugal atomization at Los Alamos National Laboratory (LANL). Improvements in the as-deposited densities and deposit efficiencies of the beryllium spray deposits will be discussed along with the corresponding thermal conductivity and outgassing behavior of these deposits.

  4. Combustion synthesis and effects of processing parameters on physical properties of {alpha}-alumina

    SciTech Connect

    Collins, M.V.; Hirschfeld, D.A.; Shea, L.E.

    2000-01-04

    Fine particle porous {alpha}-alumina has been prepared by a wet chemical method of combustion synthesis using an aqueous precursor containing aluminum nitrate (oxidizer) and carbohydrazide, an organic fuel as starting materials. The aluminum nitrate and carbohydrazide were reacted exothermically at 400--600 C. The synthesis of {alpha}-alumina ({alpha}-Al{sub 2}O{sub 3}) was used as a model for understanding the effects of processing parameters on physical properties such as surface area, average pore size, and residual carbon content. The porous powders were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), BET surface area analysis and elemental analysis. The decomposition of the starting materials was investigated using differential thermal and thermogravimetric analyses (DTA/TGA). It has been shown that the furnace temperature, fuel/oxidizer ratio, and precursor water content can be tailored to produce powders with different physical properties.

  5. Solid formulations by a nanocrystal approach: critical process parameters regarding scale-ability of nanocrystals for tableting applications.

    PubMed

    Tuomela, Annika; Laaksonen, Timo; Laru, Johanna; Antikainen, Osmo; Kiesvaara, Juha; Ilkka, Jukka; Oksala, Olli; Rönkkö, Seppo; Järvinen, Kristiina; Hirvonen, Jouni; Peltonen, Leena

    2015-05-15

    Nanocrystallization is among the foremost drug delivery platform approaches for the commercial development of poorly soluble drugs. There exists an urge to enable a universal shift of the production of the solid nanocrystal formulations from laboratory scale to industrially feasible scale. The success of any formulation development depends on its transferability to large scale manufacture. The objectives of the study were to increase the nanocrystallization batch size and to screen and optimize parameters for industrially feasible itraconazole (ITC) and indomethacin (IND) nanocrystal composition for tablet formulation. Thus, ITC and IND were transformed into nanocrystal suspensions, using an increased batch size of a wet milling process, freeze-dried, and further developed into both direct compression (DC) and granulated (G) tableting masses. According to the investigated powder and tablet properties (true density, flowability, dose uniformity, maximum upper punch force, crushing strength, dissolution and disintegration) and stability testings, it was clear that the amount of the nanocrystals in the solid tablet formulation is critical in order to fully utilize the benefits of the nanocrystals, i.e., fast dissolution, and to produce high-quality tablets. The DC designs of both the model drugs with compositions including 40% of freeze-dried nanocrystalline drug powder outperformed the corresponding granulated tablets in all parameters after the stability surveillance. PMID:25746735

  6. FAME: Freeform Active Mirrors Experiment: manufacturing process development

    NASA Astrophysics Data System (ADS)

    Challita, Zalpha; Hugot, Emmanuel; Venema, Lars; Schnetler, Hermine; Ferrari, Marc; Cuby, Jean-Gabriel

    2014-07-01

    Extreme freeform mirrors couple a non-axisymmetrical shape and an extreme asphericity, i.e. more than one millimeter of deviation from the best fit sphere. In astronomical instrumentation, such a large asphericity allows compact instruments, using less optical components. However, the lack of freeform mirrors manufacturing facilities is a real issue. We present the concept and development of an innovative manufacturing process based on plasticity forming which allow imprinting permanent deformations on mirrors, following a pre-defined mold. The aim of this activity, pursued in the frame of the OPTICON-FAME (Freeform Active Mirrors Experiment) project, is to demonstrate the suitability of this method for VIS/NIR/MIR applications. The process developed can operate on thin and flat polished initial substrates. Three study cases have been highlighted by FEA (Finite Element Analysis) and the real tests associated were performed on thin substrates in AISI420b stainless steel with 100 mm optical diameter. A comparison between FEA and tests is performed to study the evolution of the mechanical behaviour and the optical quality. The opto-mechanical results will allow a fine tuning of FEA parameters to optimize the residual form errors obtained through this process to converge toward an innovative and recurrent process.

  7. Algebraic processing technique for extracting frequency-dependent shear-wave splitting parameters in an anisotropic medium

    NASA Astrophysics Data System (ADS)

    Han, Kai-Feng; Zeng, Xin-Wu

    2011-06-01

    Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth (1993), a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component VSP data in frequency-dependent medium has been developed. By using this dual source cumulative rotation technique in the frequency-domain (DCTF), anisotropic parameters, including polarization direction of the shear-waves and timedelay between the fast and slow shear-waves, can be estimated for each frequency component in the frequency domain. It avoids the possible error which comes from using a narrow-band filter in the current commonly used method. By using synthetic seismograms, the feasibility and validity of the technique was tested and a comparison with the currently used method was also given. The results demonstrate that the shear-wave splitting parameters frequency dependence can be extracted directly from four-component seismic data using the DCTF. In the presence of larger scale fractures, substantial frequency dependence would be found in the seismic frequency range, which implies that dispersion would occur at seismic frequencies. Our study shows that shear-wave anisotropy decreases as frequency increases.

  8. The Neutral Atmosphere Parameters on Measurements Using the Artificial Periodic Irregularities. Techniques, processing, results.

    NASA Astrophysics Data System (ADS)

    Tolmacheva, Ariadna V.; Bakhmetieva, Nataliya V.; Grigoriev; Kalinina, Elena E.

    The measurements with the aid of the artificial periodic irregularities (APIs) were begun in 1990. The APIs are created in the ionosphere illuminated by a high power HF radio wave of a frequency below the critical one. The APIs diagnostics is based upon observation of the Bragg backscatter of the pulsed probe radio waves from the periodic structure. The amplitudes and phases of the probe signals back scattered by the APIs are measured. At the E-region heights the APIs relax in the ambipolar diffusion process. Based on this fact we could determine the neutral atmosphere parameters suggesting that the processes of isothermal on small scales (3-5 km) and the electron, ion and neutral temperatures are equal at the E-region heights. The atmospheric height scale H and the neutral atmospheric temperature T are determined on the height dependence of the relaxation times tau(z). The altitude step is about 3 km. Whole height interval of the measurements of τ is equal to about 20-30 km. Selecting small height intervals step by step we obtain altitude dependences T(z), nu(z) and rho(z). Such a way was employed because the steady state is achieved on the scales 20-30 km for a long time. We obtained a lot of information about dynamical phenomena in the lower thermosphere. These results are presented in the report. Firstly, there were temperature profiles with minimum about 100-140 K above 100 km in the equinoctial periods. But in summer of 1999 temperature maximum was observed on z = 100 km. Secondary, there were often profiles with the wave-like variations and with the vertical scale of about to 4-6 km. The temporal variations of the atmospheric parameters had periods from 15 minutes to some hours. These variations caused by the propagation of the internal gravity and tide waves. Planetary waves produce the longer temporal variations. Thirdly, we observed some cases of the instability growth. The dependencies of the atmospheric parameters on the solar and geomagnetic activity

  9. Comparison of the predictive value of plateletcrit with various other blood parameters in gestational diabetes development.

    PubMed

    Sahbaz, Ahmet; Cicekler, Humeyra; Aynioglu, Oner; Isik, Hatice; Ozmen, Ulku

    2016-07-01

    Gestational diabetes is the most encountered metabolic disease in pregnancy and affects both the mother and fetus adversely. Low-grade subchronic inflammation is associated with gestational diabetes development. Platelets (PLT) play role in blood coagulation and inflammatory process. We aimed to compare the various platelet indices in patients with GDM and healthy pregnant controls and to determine whether PLT indices are useful in Gestational diabetes diagnosis. The present study was performed at the Zonguldak Bulent Ecevit University, School of Medicine, Department of Obstetrics and Gynecology. Statistically significant relationships with plateletcrit, mean platelet volume, and platelet distribution width and patients with GDM were found (p < 0.001). Plateletcrit had higher sensitivity and specificity than other platelet indices. Although plateletcrit is a largely unknown or an underestimated parameter in complete blood count, it gives more precise information than platelet count and mean platelet volume. Platelet-related indices and their determination are inexpensive and routinely ordered markers, the significance of which is often ignored. They may be useful in screening for gestational diabetes as an adjunct to oral glucose tolerance test. PMID:26758049

  10. Extrusion and Extruded Products: Changes in Quality Attributes as Affected by Extrusion Process Parameters: A Review.

    PubMed

    Alam, M S; Kaur, Jasmeen; Khaira, Harjot; Gupta, Kalika

    2016-01-01

    Extrusion of foods is an emerging technology for the food industries to process and market a large number of products of varying size, shape, texture, and taste. Extrusion cooking technology has led to production of wide variety of products like pasta, breakfast cereals, bread crumbs, biscuits, crackers, croutons, baby foods, snack foods, confectionery items, chewing gum, texturized vegetable protein (TVP), modified starch, pet foods, dried soups, dry beverage mixes etc. The functional properties of extruded foods plays an important role for their acceptability which include water absorption, water solubility, oil absorption indexes, expansion index, bulk density and viscosity of the dough. The aim of this review is to give the detailed outlines about the potential of extrusion technology in development of different types of products and the role of extrusion-operating conditions and their effect on product development resulting in quality changes i.e physical, chemical, and nutritional, experienced during the extrusion process. PMID:25574813

  11. Plasma Parameters of SRF Cavities for Radio-Frequency Discharge Processing

    NASA Astrophysics Data System (ADS)

    Upadhyay, Janardan; Popovic, Svetozar; Vuskovic, Lepsha; Valente-Feliciano, Anne-Marie; Phillips, Larry

    2012-10-01

    Superconducting radio frequency (SRF) cavities of bulk Niobium are accelerating field-generating components of particle accelerators. Cavities are designed to support TM modes at a resonant frequency, which usually serve as their identifier. RF plasma surface modification dry-etching technology as an alternative to the currently existing wet etching technology requires a different RF coupling regime. The choice of power generator frequency greatly affects the field and plasma parameters distribution over the cavity. These are adjusted by a coaxial centerline antenna to provide for optimum level of plasma sheath uniformity. In the search for best etching conditions, we are opting for radio frequency (13.56 MHz, 100 MHz) and microwave frequency plasma (2.45 GHz) in Ar/Cl2 gas mixture. We have developed five optical probes for simultaneous spectroscopic measurements of the plasma properties at five points inside the cavity. The electron temperature and density measurement at the same set of points will be also measured with a Langmuir probe. The measurement of plasma parameters at different pressure and power for the chosen frequency set with varying chlorine content will be presented.

  12. Development of wavelet-ANN models to predict water quality parameters in Hilo Bay, Pacific Ocean.

    PubMed

    Alizadeh, Mohamad Javad; Kavianpour, Mohamad Reza

    2015-09-15

    The main objective of this study is to apply artificial neural network (ANN) and wavelet-neural network (WNN) models for predicting a variety of ocean water quality parameters. In this regard, several water quality parameters in Hilo Bay, Pacific Ocean, are taken under consideration. Different combinations of water quality parameters are applied as input variables to predict daily values of salinity, temperature and DO as well as hourly values of DO. The results demonstrate that the WNN models are superior to the ANN models. Also, the hourly models developed for DO prediction outperform the daily models of DO. For the daily models, the most accurate model has R equal to 0.96, while for the hourly model it reaches up to 0.98. Overall, the results show the ability of the model to monitor the ocean parameters, in condition with missing data, or when regular measurement and monitoring are impossible. PMID:26140748

  13. ON DEVELOPING CLEANER ORGANIC UNIT PROCESSES

    EPA Science Inventory

    Organic waste products, potentially harmful to the human health and the environment, are primarily produced in the synthesis stage of manufacturing processes. Many such synthetic unit processes, such as halogenation, oxidation, alkylation, nitration, and sulfonation are common to...

  14. Processing to determine optical parameters of atherosclerotic disease from phantom and clinical intravascular optical coherence tomography three-dimensional pullbacks.

    PubMed

    Shalev, Ronny; Gargesha, Madhusudhana; Prabhu, David; Tanaka, Kentaro; Rollins, Andrew M; Lamouche, Guy; Bisaillon, Charles-Etienne; Bezerra, Hiram G; Ray, Soumya; Wilson, David L

    2016-04-01

    Analysis of intravascular optical coherence tomography (IVOCT) data has potential for real-time in vivo plaque classification. We developed a processing pipeline on a three-dimensional local region of support for estimation of optical properties of atherosclerotic plaques from coronary artery, IVOCT pullbacks. Using realistic coronary artery disease phantoms, we determined insignificant differences in mean and standard deviation estimates between our pullback analyses and more conventional processing of stationary acquisitions with frame averaging. There was no effect of tissue depth or oblique imaging on pullback parameter estimates. The method's performance was assessed in comparison with observer-defined standards using clinical pullback data. Values (calcium [Formula: see text], lipid [Formula: see text], and fibrous [Formula: see text]) were consistent with previous measurements obtained by other means. Using optical parameters ([Formula: see text], [Formula: see text], [Formula: see text]), we achieved feature space separation of plaque types and classification accuracy of [Formula: see text]. Despite the rapid [Formula: see text] motion and varying incidence angle in pullbacks, the proposed computational pipeline appears to work as well as a more standard "stationary" approach. PMID:27213167

  15. Effects of Flux Precoating and Process Parameter on Welding Performance of Inconel 718 Alloy TIG Welds

    NASA Astrophysics Data System (ADS)

    Lin, Hsuan-Liang; Wu, Tong-Min; Cheng, Ching-Min

    2014-01-01

    The purpose of this study is to investigate the effect of activating flux on the depth-to-width ratio (DWR) and hot cracking susceptibility of Inconel 718 alloy tungsten inert gas (TIG) welds. The Taguchi method is employed to investigate the welding parameters that affect the DWR of weld bead and to achieve optimal conditions in the TIG welds that are coated with activating flux in TIG (A-TIG) process. There are eight single-component fluxes used in the initial experiment to evaluate the penetration capability of A-TIG welds. The experimental results show that the Inconel 718 alloy welds precoated with 50% SiO2 and 50% MoO3 flux were provided with better welding performance such as DWR and hot cracking susceptibility. The experimental procedure of TIG welding process using mixed-component flux and optimal conditions not only produces a significant increase in DWR of weld bead, but also decreases the hot cracking susceptibility of Inconel 718 alloy welds.

  16. Variation in biochemical parameters in different parts of potato tubers for processing purposes.

    PubMed

    Bandana; Sharma, Vineet; Kaushik, S K; Singh, Brajesh; Raigond, Pinky

    2016-04-01

    The present study was conducted to estimate the variation in bio-chemical parameters among eight different parts viz. bud end cortex, bud end medulla, central cortex, central medulla, pith, stem end cortex, stem end medulla and peel of potato tuber of processing varieties. Concentration of dry matter, reducing sugar, sucrose and starch content were higher in cortical region than in medullar region of stem end, bud end and central portion. Variety Kufri Chipsona-1 had maximum dry matter content in stem end cortex (SEC 30.34 %), followed by Kufri Frysona (SEC 27.71 %). Mean reducing sugar values were comparatively more in bud end cortex (BEC 111.3 mg/100 g Fresh Weight) and lowest in stem end medulla (SEM 44.05 mg/100 g FW). Bio-chemical contents varied considerably within different parts of tuber as well as in different genotypes. The information generated in this study can help processors for effective utilization of potato for various types of processing products viz., chips and French fries. PMID:27413232

  17. Influence of process and tool design parameters in press forming of a thermoplastic composite sheet

    SciTech Connect

    Shaffer, T.M.; Mallick, P.K.

    1994-12-31

    The goal of this work is to investigate the effects of several process and tool design parameters (preheat and mold temperature, forming depth and speed, bend radius, cooling time, blank holder force, ironing, and presence of mold bottom) in the press forming of a glass fiber reinforced polypropylene sheet. Rectangular strips are formed into hat section shapes in a process similar to deep drawing. Part spring back and several qualitative factors are used to evaluate the formed parts. It is concluded that a key factor for successful solid state forming of this material is the precise control of the blank temperature. High forming speeds and elevated molding fixture temperatures improve part quality and reduce cycle times. Bend radius was found to have little to no effect on part spring back, but larger radii improve qualitative characteristics. Compression of the part at the end of the forming stroke can remove surface irregularities and delaminations from the finished parts if larger part depths are required. Stretching the material is undesirable because it causes large amounts of delamination, fiber breakage and matrix fracture.

  18. Parameter study of r-process lanthanide production and heating rates in kilonovae

    NASA Astrophysics Data System (ADS)

    Lippuner, Jonas; Roberts, Luke F.

    2015-04-01

    Explosive r-process nucleosynthesis in material ejected during compact object mergers may lead to radioactively powered transients called kilonovae. The timescale and peak luminosity of these transients are sensitive to the composition of the material after nuclear burning ceases, as the composition determines the local heating rate from nuclear decays and the opacity. The presence of lanthanides in the ejecta can drastically increase the opacity. We use the new general-purpose nuclear reaction network SkyNet to run a parameter study of r-process nucleosynthesis for a range of initial electron fractions Ye, initial entropies s, and density decay timescales τ. We find that the ejecta is lanthanide-free for Ye >~ 0 . 22 - 0 . 3 , depending on s and τ. The heating rate is insensitive to s and τ, but certain, larger values of Ye lead to reduced heating rates, because single nuclides dominate the heating. With a simple model we estimate the luminosity, time, and effective temperature at the peak of the light curve. Since the opacity is much lower in the lanthanide-free case, we find the luminosity peaks much earlier at ~ 1 day vs. ~ 15 days in the lanthanide-rich cases. Although there is significant variation in the heating rate with Ye, changes in the heating rate do not mitigate the effect of the lanthanides. This research is partially supported by NSF under Award Numbers AST-1333520 and AST-1205732.

  19. Characterization Of An EBL System: The Influence Of Process Parameters On Thickness Resist And Engraving Shapes

    SciTech Connect

    D'Urso, G.; Longo, M.; Ravasio, C.; Maccarini, G.

    2011-01-17

    In LIGA process, the low flexibility due to the use of masks might be overcome using the electron beam of a scansion electron microscope (SEM) instead of the synchrotron radiation. In this way, through the vector control of the beam, it is possible to irradiate a specific path on the resist without using any mask. Anyway, it is important to remark that the Electron Beam Lithography (EBL) can not include all the applications of the X-ray LIGA technique but it could be a valid alternative only for some specific uses. In particular, some limits concerning the impression of high thickness resists are expected. An EBL system based on a SEM was recently implemented by the authors and some tests were carried out to characterize the device performances. Aim of this work is to asses the system performances in terms of maximum impressible thickness resist and shape of the engraved entities. Several tests were carried out by varying the resist thickness and the process parameters.

  20. Optimization of process parameters for drilled hole quality characteristics during cortical bone drilling using Taguchi method.

    PubMed

    Singh, Gurmeet; Jain, Vivek; Gupta, Dheeraj; Ghai, Aman

    2016-09-01

    Orthopaedic surgery involves drilling of bones to get them fixed at their original position. The drilling process used in orthopaedic surgery is most likely to the mechanical drilling process and there is all likelihood that it may harm the already damaged bone, the surrounding bone tissue and nerves, and the peril is not limited at that. It is very much feared that the recovery of that part may be impeded so that it may not be able to sustain life long. To achieve sustainable orthopaedic surgery, a surgeon must try to control the drilling damage at the time of bone drilling. The area around the holes decides the life of bone joint and so, the contiguous area of drilled hole must be intact and retain its properties even after drilling. This study mainly focuses on optimization of drilling parameters like rotational speed, feed rate and the type of tool at three levels each used by Taguchi optimization for surface roughness and material removal rate. The confirmation experiments were also carried out and results found with the confidence interval. Scanning electrode microscopy (SEM) images assisted in getting the micro level information of bone damage. PMID:27254280

  1. Large-scale erosion processes and parameters derived from a modeling of the Messinian salinity crisis

    NASA Astrophysics Data System (ADS)

    Loget, N.; Davy, P.; van den Driessche, J.

    2003-04-01

    The closing of the Gibraltar strait during Messinian have produced a drop of the sea level of about 1500 m in less than half a million year. This certainly constitutes one of the largest perturbation of erosion systems in the Earth, whose analysis in terms of form and dynamics should bring invaluable constraints on erosion processes and parameters. In addition to a precise chronology of the bulk crisis, the main data consists of the reconstruction of paleocanyons, that were eroded during sea drop and refilled during sea rise. The Rhone's canyon is certainly the most documented, with numerous seismic lines and boreholes. We have now a reasonable estimation of the canyon profile from its outlet to the Bresse graben, more 500 km upslope. Sparse data are also available in the Languedoc region, in the Pyrenees, for some drainage basins of the Var-Ligure coast, in the gulf of Valence. A particularity of this erosion phase was to propagate very far inland along the main rivers, but in a very localized way in the sense that hillslopes or upslope drainage basins were barely affected. All these data were compiled in a database that we used to constrain erosion processes. We assume that the erosion law belongs to the classical power-law framework, where the erosion flux depends on local slope s, and water flow q, such as: e=k qmsn-ec, where k and ec are two constants which depend on material strength properties, and m and n are two exponents which are found to play an important role in the time-length scaling. The transfer model must be completed by a transfer or deposition terms that we assume to be controlled by a deposition length Ld. If Ld is very small, the model comes to the transport-limited case where the height variation is proportional to the gradient of the erosion flux e. In contrast if Ld is very large, rivers can carry all the eroded sediment out; the process is usually called detachment-limited. We simulate the erosion dynamics, induced by the Messinian sea

  2. Developing Cultural Differences in Face Processing

    ERIC Educational Resources Information Center

    Kelly, David J.; Liu, Shaoying; Rodger, Helen; Miellet, Sebastien; Ge, Liezhong; Caldara, Roberto

    2011-01-01

    Perception and eye movements are affected by culture. Adults from Eastern societies (e.g. China) display a disposition to process information "holistically," whereas individuals from Western societies (e.g. Britain) process information "analytically." Recently, this pattern of cultural differences has been extended to face processing. Adults from…

  3. Contact-free determination of human body segment parameters by means of videometric image processing of an anthropomorphic body model

    NASA Astrophysics Data System (ADS)

    Hatze, Herbert; Baca, Arnold

    1993-01-01

    The development of noninvasive techniques for the determination of biomechanical body segment parameters (volumes, masses, the three principal moments of inertia, the three local coordinates of the segmental mass centers, etc.) receives increasing attention from the medical sciences (e,.g., orthopaedic gait analysis), bioengineering, sport biomechanics, and the various space programs. In the present paper, a novel method is presented for determining body segment parameters rapidly and accurately. It is based on the video-image processing of four different body configurations and a finite mass-element human body model. The four video images of the subject in question are recorded against a black background, thus permitting the application of shape recognition procedures incorporating edge detection and calibration algorithms. In this way, a total of 181 object space dimensions of the subject's body segments can be reconstructed and used as anthropometric input data for the mathematical finite mass- element body model. The latter comprises 17 segments (abdomino-thoracic, head-neck, shoulders, upper arms, forearms, hands, abdomino-pelvic, thighs, lower legs, feet) and enables the user to compute all the required segment parameters for each of the 17 segments by means of the associated computer program. The hardware requirements are an IBM- compatible PC (1 MB memory) operating under MS-DOS or PC-DOS (Version 3.1 onwards) and incorporating a VGA-board with a feature connector for connecting it to a super video windows framegrabber board for which there must be available a 16-bit large slot. In addition, a VGA-monitor (50 - 70 Hz, horizontal scan rate at least 31.5 kHz), a common video camera and recorder, and a simple rectangular calibration frame are required. The advantage of the new method lies in its ease of application, its comparatively high accuracy, and in the rapid availability of the body segment parameters, which is particularly useful in clinical practice

  4. Low voltage resist processes developed for MAPPER tool first exposures

    NASA Astrophysics Data System (ADS)

    Rio, D.; Constancias, C.; van Nieuwstadt, J.; Vijverberg, J.; Derrough, S.; Icard, B.; Pain, L.

    2010-05-01

    The FP7 European project MAGIC [1] aims at designing a multi electron beam machine. In the frame of this project, LETI evaluates a multibeam tool from MAPPER lithography [2]. Each beam has an acceleration voltage of 5kV. A tool has been installed in LETI premises in July 2009. In order to prepare its evaluation, preliminary work was performed on Gaussian beam tools down to 5kV. It aimed at the determination of a stable and robust resist process allowing high resolution at 5kV. Then those results were used to characterize MAPPER tool performances. Meeting the requirements of high resolution and low roughness at low voltage, Dow Corningmolecular glass HSQ (hydrogen silsesquioxane) and MicroChem PMMA (polymethylmethacrylate) were used to test MAPPER tool as negative and positive tone resist references. We did exposures at beam acceleration voltages from 5 kV up to 100 kV. Different post application bake (PAB) temperatures were applied to resist. Several developer concentrations were also tested. The impact of those three parameters on contrast and resolution was checked. Resists chemical characterization was performed with FTIR (Fourier transform infra red) spectroscopy in order to understand the mechanisms leading to the observed variations of contrast and exposure dose as process parameters are changed. The main purpose of this work was to show that high resolution can be achieved at 5kV. First exposures performed with MAPER tool confirmed those results.

  5. Development of one-dimensional solutions for water infiltration. Analysis and parameters estimation

    NASA Astrophysics Data System (ADS)

    Sayah, Boumediene; Gil-Rodríguez, María; Juana, Luis

    2016-04-01

    The design of an irrigation system requires proper understanding of the infiltration process. Two original approximate solutions were developed in this study in order to determine one-dimensional vertical infiltration and profile water distribution. The Boltzmann transformation was used to solve the Richards equation. The accuracy of the solutions was verified by comparing results obtained with Hydrus-1D simulations. The solutions were also compared with the US Department of Agriculture-Natural Resources and Conservation Service (USDA-NRCS) intake families for infiltrated depths between 2 and 16 cm, using soils from Carsel and Parrish database. Simulations results of both solutions were in close agreement with Hydrus-1D. For all the cases studied, the corresponding root mean square error (RMSE) values were up to 0.56 cm, with coefficients of correlation (R2) larger than 0.99. Therefore, The comparison shows inexact matching, with acceptable correspondence, between simulated soils and NRCS curve numbers, The procedure developed to fit the USDA-NRCS intake families with the proposed solutions leads to characterize each family by the van Genuchten-Mualem parameters, and an initial soil water content. Furthermore, results suggests to consider initial water content in fine-textured soils. In the case of intake families, initial water content began to affect in Family 0.5 and became very decisive in the Family 0.05. Additionally, the proposed method, which are applicable to any descriptor of unsaturated hydraulic properties, have practical application, including accurate determination of the sorptivity of a soil at various water contents, and requires low computational effort.

  6. BENCH SCALE SALTSTONE PROCESS DEVELOPMENT MIXING STUDY

    SciTech Connect

    Cozzi, A.; Hansen, E.

    2011-08-03

    The Savannah River National Laboratory (SRNL) was requested to develop a bench scale test facility, using a mixer, transfer pump, and transfer line to determine the impact of conveying the grout through the transfer lines to the vault on grout properties. Bench scale testing focused on the effect the transfer line has on the rheological property of the grout as it was processed through the transfer line. Rheological and other physical properties of grout samples were obtained prior to and after pumping through a transfer line. The Bench Scale Mixing Rig (BSMR) consisted of two mixing tanks, grout feed tank, transfer pump and transfer hose. The mixing tanks were used to batch the grout which was then transferred into the grout feed tank. The contents of the feed tank were then pumped through the transfer line (hose) using a progressive cavity pump. The grout flow rate and pump discharge pressure were monitored. Four sampling stations were located along the length of the transfer line at the 5, 105 and 205 feet past the transfer pump and at 305 feet, the discharge of the hose. Scaling between the full scale piping at Saltstone to bench scale testing at SRNL was performed by maintaining the same shear rate and total shear at the wall of the transfer line. The results of scaling down resulted in a shorter transfer line, a lower average velocity, the same transfer time and similar pressure drops. The condition of flow in the bench scale transfer line is laminar. The flow in the full scale pipe is in the transition region, but is more laminar than turbulent. The resulting plug in laminar flow in the bench scale results in a region of no-mixing. Hence mixing, or shearing, at the bench scale should be less than that observed in the full scale, where this plug is non existent due to the turbulent flow. The bench scale tests should be considered to be conservative due to the highly laminar condition of flow that exists. Two BSMR runs were performed. In both cases, wall

  7. Encapsulation of immunoglobulin G by solid-in-oil-in-water: effect of process parameters on microsphere properties.

    PubMed

    Marquette, Sarah; Peerboom, Claude; Yates, Andrew; Denis, Laurence; Goole, Jonathan; Amighi, Karim

    2014-04-01

    Antibodies (Abs) are prone to a variety of physical and chemical degradation pathways, which require the development of stable formulations and specific delivery strategies. In this study, injectable biodegradable and biocompatible polymeric particles were employed for controlled-release dosage forms and the encapsulation of antibodies into polylactide-co-glycolide (PLGA) based microspheres was explored. In order to avoid stability issues which are commonly described when water-in-oil (w/o) emulsion is used, a solid-in-oil-in-water (s/o/w) method was developed and optimized. The solid phase was made of IgG microparticles and the s/o/w process was evaluated as an encapsulation method using a model Ab molecule (polyclonal bovine immunoglobulin G (IgG)). The methylene chloride (MC) commonly used for an encapsulation process was replaced by ethyl acetate (EtAc), which was considered as a more suitable organic solvent in terms of both environmental and human safety. The effects of several processes and formulation factors were evaluated on IgG:PLGA microsphere properties such as: particle size distribution, drug loading, IgG stability, and encapsulation efficiency (EE%). Several formulations and processing parameters were also statistically identified as critical to get reproducible process (e.g. the PLGA concentration, the volume of the external phase, the emulsification rate, and the quantity of IgG microparticles). The optimized encapsulation method has shown a drug loading of up to 6% (w/w) and an encapsulation efficiency of up to 60% (w/w) while preserving the integrity of the encapsulated antibody. The produced microspheres were characterized by a d(0.9) lower than 110 μm and showed burst effect lower than 50% (w/w). PMID:24184674

  8. Ceramic component manufacturing process development. Final report

    SciTech Connect

    Robinson, S.

    1996-09-30

    Ceramic materials are well suited for applications where temperature, wear, and corrosion resistance are necessary. The toughness and wear resistance properties that make ceramics desirable, also make fabrication of parts difficult. The objective of this CRADA was to increase the grinding efficiency on Ceradyne Incorporated silicon nitride. This was to be accomplished through optimization of grinding wheel life and increasing silicon nitride material removal rates. Experiments were conducted to determine the relationship between grinding parameters, wheel wear, and material removal rates. Due to excessive, unexplained variation in the experimental results, a consistent relationship between the selected grinding parameters and wheel wear could not be established. Maximum material removal rates were limited by spindle and table drive power. Additional experiments were conducted to evaluate high speed grinding. When compared to conventional grinding speeds, the material removal rates using high speed grinding (13,000 SFM) increased by a factor of five to ten with no degradation of fracture strength.

  9. Process parameters and morphology in puerarin, phospholipids and their complex microparticles generation by supercritical antisolvent precipitation.

    PubMed

    Li, Ying; Yang, Da-Jian; Chen, Shi-Lin; Chen, Si-Bao; Chan, Albert Sun-Chi

    2008-07-01

    The aim of the study was to develop and evaluate a new method for the production of puerarin phospholipids complex (PPC) microparticles. The advanced particle formation method, solution enhanced dispersion by supercritical fluids (SEDS), was used for the preparation of puerarin (Pur), phospholipids (PC) and their complex particles for the first time. Evaluation of the processing variables on PPC particle characteristics was also conducted. The processing variables included temperature, pressure, solution concentration, the flow rate of supercritical carbon dioxide (SC-CO2) and the relative flow rate of drug solution to CO2. The morphology, particle size and size distribution of the particles were determined. Meanwhile Pur and phospholipids were separately prepared by gas antisolvent precipitation (GAS) method and solid characterization of particles by the two supercritical methods was also compared. Pur formed by GAS was more orderly, purer crystal, whereas amorphous Pur particles between 0.5 and 1microm were formed by SEDS. The complex was successfully obtained by SEDS exhibiting amorphous, partially agglomerated spheres comprised of particles sized only about 1microm. SEDS method may be useful for the processing of other pharmaceutical preparations besides phospholipids complex particles. Furthermore adopting a GAS process to recrystallize pharmaceuticals will provide a highly versatile methodology to generate new polymorphs of drugs in addition to conventional techniques. PMID:18440736

  10. Effects of processed parameters on the magnetic performance of a powder magnetic core

    NASA Astrophysics Data System (ADS)

    Xie, Ding-Zhou; Lin, Kuan-Hong; Lin, Shun-Tian

    2014-03-01

    The goal of this study is to develop a high magnetic flux density and low iron loss powder magnetic core with insulated layer coating on pure iron powders of varying sizes. After processing the phosphate treatment, the insulated layer Zn3(PO4)2 was coated onto the iron powder surface. It not only maintained the magnetic flux density of pure iron, but also enhanced the electrical resistivity of the magnetic core by reducing eddy current loss, which allowed a wider frequency range. In addition, the annealing treatment after the compression process raised the magnetic flux density of the magnetic core; however, an annealing temperature above 200 °C caused the binder to decompose, resulting in decreased electrical resistivity. Experimental results indicate that the best magnetic performances were achieved with a powder magnetic core of fine and coarse iron powder proportion of 2:1, phosphate treatment of 90 s, and an annealing temperature of 200 °C.

  11. Spray granulation: importance of process parameters on in vitro and in vivo behavior of dried nanosuspensions.

    PubMed

    Figueroa, Carlos E; Bose, Sonali

    2013-11-01

    The use of fluid bed granulation for drying of pharmaceutical nanoparticulates on micron-sized granule substrates is a relatively new technique, with limited understanding in the current literature of the effects of process parameters on the physical properties of the dried nanoparticle powders. This work evaluated the effects of spray mode, spray rate and atomizing pressure for spray granulation of drug nanosuspensions through a systematic study. Naproxen and a proprietary Novartis compound were converted into nanosuspensions through wet media milling and dried onto a mannitol based substrate using spray granulation. For naproxen, various physical properties of the granules, as well as the in vitro re-dispersion and dissolution characteristics of the nano-crystals, were measured. It was found that the spray mode had the most drastic effect, where top spray yielded smaller re-dispersed particle sizes and faster release rates of drug from granules than bottom spray. This was attributed to the co-current spraying in bottom spray resulting in denser, homogenous films on the substrate. Similar in vitro results were obtained for the proprietary molecule, Compound A. In vivo studies in beagle dogs with Compound A showed no significant difference between the liquid and the dried forms of the nanosuspension in terms of overall AUC, differences were observed in the tmax which correlated with the rank ordering observed from the in vitro dissolution profiles. These findings make spray granulation amenable to the production of powders with desired processing and handling properties, without compromising the overall exposure of the compound under investigation. PMID:23916460

  12. Effect of Process Parameters on Dynamic Mechanical Performance of FDM PC/ABS Printed Parts Through Design of Experiment

    NASA Astrophysics Data System (ADS)

    Mohamed, Omar Ahmed; Masood, Syed Hasan; Bhowmik, Jahar Lal; Nikzad, Mostafa; Azadmanjiri, Jalal

    2016-07-01

    In fused deposition modeling (FDM) additive manufacturing process, it is often difficult to determine the actual levels of process parameters in order to achieve the best dynamic mechanical properties of FDM manufactured part. This is mainly due to the large number of FDM parameters and a high degree of interaction between the parameters affecting such properties. This requires a large number of experiments to be determined. This paper presents a study on the influence of six FDM process parameters (layer thickness, air gap, raster angle, build orientation, road width, and number of contours) on the dynamic mechanical properties of the FDM manufactured parts using the fraction factorial design. The most influential parameters were statistically obtained through the analysis of variance (ANOVA) technique, and the results indicate that the layer thickness, the air gap, and the number of contours have the largest impact on dynamic mechanical properties. The optimal parameters for maximum dynamic mechanical properties were found to be layer thickness of 0.3302 mm, air gap of 0.00 mm, raster angle of 0.0°, build orientation of 0.0°, road width of 0.4572 mm, and 10 contours. Finally, a confirmation experiment was performed using optimized levels of process parameters, which showed good fit with the estimated values.

  13. Effect of Process Parameters on Dynamic Mechanical Performance of FDM PC/ABS Printed Parts Through Design of Experiment

    NASA Astrophysics Data System (ADS)

    Mohamed, Omar Ahmed; Masood, Syed Hasan; Bhowmik, Jahar Lal; Nikzad, Mostafa; Azadmanjiri, Jalal

    2016-06-01

    In fused deposition modeling (FDM) additive manufacturing process, it is often difficult to determine the actual levels of process parameters in order to achieve the best dynamic mechanical properties of FDM manufactured part. This is mainly due to the large number of FDM parameters and a high degree of interaction between the parameters affecting such properties. This requires a large number of experiments to be determined. This paper presents a study on the influence of six FDM process parameters (layer thickness, air gap, raster angle, build orientation, road width, and number of contours) on the dynamic mechanical properties of the FDM manufactured parts using the fraction factorial design. The most influential parameters were statistically obtained through the analysis of variance (ANOVA) technique, and the results indicate that the layer thickness, the air gap, and the number of contours have the largest impact on dynamic mechanical properties. The optimal parameters for maximum dynamic mechanical properties were found to be layer thickness of 0.3302 mm, air gap of 0.00 mm, raster angle of 0.0°, build orientation of 0.0°, road width of 0.4572 mm, and 10 contours. Finally, a confirmation experiment was performed using optimized levels of process parameters, which showed good fit with the estimated values.

  14. The influence of VAR processes and parameters on white spot formation in Alloy 718

    SciTech Connect

    Damkroger, B.K.; Kelley, J.B.; Schlienger, M.E.; Van Den Avyle, J.A.; Williamson, R.L.; Zanner, F.J.

    1994-05-01

    Significant progress has occurred lately regarding the classification, characterization, and formation of white spots during vacuum arc remelting (VAR). White spots have been generally split into three categories: discrete white spots, which are believed to be associated with undissolved material which has fallen in from the shelf, crown, or torus regions; dendritic white spots, usually associated with dendrite clusters having fallen from the electrode; and solidification white spots, believed to be caused by local perturbations in the solidifications conditions. Characteristics and proposed formation mechanisms of white spots are reviewed and discussed in context of physical processes occurring during VAR, such as fluid flow and arc behavior. Where possible, their formation mechanisms will be considered with respect to specific operating parameters. In order to more fully understand the formation of solidification white spots, an experimental program has been begun to characterize the solidification stability of Alloy 718 and variants with respect to changes in growth rate and thermal environment. A description of the experimental program and preliminary results are included.

  15. Effect of Process Parameters on Microstructure and Hardness of Oxide Dispersion Strengthened 18Cr Ferritic Steel

    NASA Astrophysics Data System (ADS)

    Nagini, M.; Vijay, R.; Rajulapati, Koteswararao V.; Rao, K. Bhanu Sankara; Ramakrishna, M.; Reddy, A. V.; Sundararajan, G.

    2016-08-01

    Pre-alloyed ferritic 18Cr steel (Fe-18Cr-2.3W-0.3Ti) powder was milled with and without nano-yttria in high-energy ball mill for varying times until steady-state is reached. The milled powders were consolidated by upset forging followed by hot extrusion. Microstructural changes were examined at all stages of processing (milling, upset forging, and extrusion). In milled powders, crystallite size decreases and hardness increases with increasing milling time reaching a steady-state beyond 5 hours. The size of Y2O3 particles in powders decreases with milling time and under steady-state milling conditions; the particles either dissolve in matrix or form atomic clusters. Upset forged sample consists of unrecrystallized grain structure with few pockets of fine recrystallized grains and dispersoids of 2 to 4 nm. In extruded and annealed rods, the particles are of cuboidal Y2Ti2O7 at all sizes and their size decreased from 15 nm to 5 nm along with significant increase in number density. The oxide particles in ODS6 are of cuboidal Y2Ti2O7 with diamond cubic crystal structure ( Fd bar{3} m) having a lattice parameter of 10.1 Å and are semicoherent with the matrix. The hardness values of extruded and annealed samples predicted by linear summation model compare well with measured values.

  16. Method of validating measurement data of a process parameter from a plurality of individual sensor inputs

    DOEpatents

    Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

    1998-01-01

    A method for generating a validated measurement of a process parameter at a point in time by using a plurality of individual sensor inputs from a scan of said sensors at said point in time. The sensor inputs from said scan are stored and a first validation pass is initiated by computing an initial average of all stored sensor inputs. Each sensor input is deviation checked by comparing each input including a preset tolerance against the initial average input. If the first deviation check is unsatisfactory, the sensor which produced the unsatisfactory input is flagged as suspect. It is then determined whether at least two of the inputs have not been flagged as suspect and are therefore considered good inputs. If two or more inputs are good, a second validation pass is initiated by computing a second average of all the good sensor inputs, and deviation checking the good inputs by comparing each good input including a present tolerance against the second average. If the second deviation check is satisfactory, the second average is displayed as the validated measurement and the suspect sensor as flagged as bad. A validation fault occurs if at least two inputs are not considered good, or if the second deviation check is not satisfactory. In the latter situation the inputs from each of all the sensors are compared against the last validated measurement and the value from the sensor input that deviates the least from the last valid measurement is displayed.

  17. Influence of ion source configuration and its operation parameters on the target sputtering and implantation process.

    PubMed

    Shalnov, K V; Kukhta, V R; Uemura, K; Ito, Y

    2012-06-01

    In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to α-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N(2)-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling. PMID:22755619

  18. Effect of Process Parameters on the Structure and Properties of Galvanized Sheets

    NASA Astrophysics Data System (ADS)

    Shukla, S. K.; Saha, B. B.; Triathi, B. D.; Avtar, Ram

    2010-07-01

    The effect of galvanizing parameters on the structure (spangle size and coating microstructure) and properties (formability and corrosion resistance) of galvanized sheets was studied in a hot dip process simulator (HDPS) in a conventional Pb bearing (0.08-0.10%) zinc bath by varying zinc bath Al level (0.10-0.28%), bath temperature (718-743 K), dipping time (1.5-3.5 s), wiping gas flow rate (200-450 lpm), nozzle distance (15-17 mm) and wiping delay time (0.1-2.1 s). Al level in the range of 0.18-0.24% in combination with dipping time of 1.5-2.5 s and bath temperature of 718-733 K results in superior formability ( E cv: ~9.3 mm) of the composite (thickness: 0.8 mm). High post-dip cooling rates (~25 K/s) suppress spangle growth (spangle size: ~2 mm). The spangle size of the GI sheet strongly influences the corrosion rate which increases from 5.8 to 9.2 mpy with a decrease in spangle size from 17.5 to 3 mm. By controlling the Al level (0.20%) in zinc bath and bath temperature (733 K), the corrosion rate of mini-spangle GI sheet can be controlled to a level of 5.5 mpy.

  19. Influence of process parameters to composite interface organization and performance of liquid/solid bimetal

    NASA Astrophysics Data System (ADS)

    Rong, S. F.; Zhu, Y. C.; Wu, Y. H.; Yang, P. H.; Duan, X. L.; Zhou, H. T.

    2015-12-01

    The liquid-solid composite technique was used to prepare the high carbon high chromium steel (HCHCS) and low alloy steel (LCS) bimetal composite materials by means of insert casting method. The influence of some process parameters such as liquid-solid ratio, preheat temperature, pouring temperature on the interface microstructure and mechanical properties were studied. Interface microstructure and element distribution were analyzed. The results show that the interface microstructure becomes better, and bonding area becomes thicker with the increase of the volume of liquid to solid ratio, preheating temperature and pouring temperature. When the liquid-solid ratio is 8:1, the preheating temperature is 300 °C and the pouring temperature is 1565 °C, a good metallurgical bonding area without any hole can be obtained with the interface combination of diffusion and fusion. The composite interface structure was composed of a core material diffusion layer, a cooling solidification layer, a direction growth layer and some cell particles. The elements of C, Cr and Mn diffuse from the HCHCS side to the alloy steel side. The microhardness increased in the gradient from the LCS side to the HCHCS. The microhardness of the interface is significantly higher than that of LCS.

  20. Process Parameter Effects on Material Removal in Magnetorheological Finishing of Borosilicate Glass

    SciTech Connect

    Miao, C.; Lambroopulos, J.C.; Jacobs, S.D.

    2010-04-14

    We investigate the effects of processing parameters on material removal for borosilicate glass. Data are collected on a magnetorheological finishing (MRF) spot taking machine (STM) with a standard aqueous magnetorheological (MR) fluid. Normal and shear forces are measured simultaneously, in situ, with a dynamic dual load cell. Shear stress is found to be independent of nanodiamond concentration, penetration depth, magnetic field strength, and the relative velocity between the part and the rotating MR fluid ribbon. Shear stress, determined primarily by the material mechanical properties, dominates removal in MRF. The addition of nanodiamond abrasives greatly enhances the material removal efficiency, with the removal rate saturating at a high abrasive concentration. The volumetric removal rate (VRR) increases with penetration depth but is insensitive to magnetic field strength. The VRR is strongly correlated with the relative velocity between the ribbon and the part, as expected by the Preston equation. A modified removal rate model for MRF offers a better estimation of MRF removal capability by including nanodiamond concentration and penetration depth.

  1. Process parameter effects on material removal in magnetorheological finishing of borosilicate glass.

    PubMed

    Miao, Chunlin; Lambropoulos, John C; Jacobs, Stephen D

    2010-04-01

    We investigate the effects of processing parameters on material removal for borosilicate glass. Data are collected on a magnetorheological finishing (MRF) spot taking machine (STM) with a standard aqueous magnetorheological (MR) fluid. Normal and shear forces are measured simultaneously, in situ, with a dynamic dual load cell. Shear stress is found to be independent of nanodiamond concentration, penetration depth, magnetic field strength, and the relative velocity between the part and the rotating MR fluid ribbon. Shear stress, determined primarily by the material mechanical properties, dominates removal in MRF. The addition of nanodiamond abrasives greatly enhances the material removal efficiency, with the removal rate saturating at a high abrasive concentration. The volumetric removal rate (VRR) increases with penetration depth but is insensitive to magnetic field strength. The VRR is strongly correlated with the relative velocity between the ribbon and the part, as expected by the Preston equation. A modified removal rate model for MRF offers a better estimation of MRF removal capability by including nanodiamond concentration and penetration depth. PMID:20357881

  2. Effect of process design and operating parameters on aerobic methane oxidation in municipal WWTPs.

    PubMed

    Daelman, Matthijs R J; Van Eynde, Tamara; van Loosdrecht, Mark C M; Volcke, Eveline I P

    2014-12-01

    Methane is a potent greenhouse gas and its emission from municipal wastewater treatment plants (WWTPs) should be prevented. One way to do this is to promote the biological conversion of dissolved methane over stripping in aeration tanks. In this study, the well-established Activated Sludge Model n°1 (ASM1) and Benchmark Simulation Model n°1 (BSM1) were extended to study the influence of process design and operating parameters on biological methane oxidation. The aeration function used in BSM 1 was upgraded to more accurately describe gas-liquid transfer of oxygen and methane in aeration tanks equipped with subsurface aeration. Dissolved methane could be effectively removed in an aeration tank at an aeration rate that is in agreement with optimal effluent quality. Subsurface bubble aeration proved to be better than surface aeration, while a CSTR configuration was superior to plug flow conditions in avoiding methane emissions. The conversion of methane in the activated sludge tank benefits from higher methane concentrations in the WWTP's influent. Finally, if an activated sludge tank is aerated with methane containing off-gas, a limited amount of methane is absorbed and converted in the mixed liquor. This knowledge helps to stimulate the methane oxidizing capacity of activated sludge in order to abate methane emissions from wastewater treatment to the atmosphere. PMID:25225767

  3. Effect of Process Parameters on Microstructure and Hardness of Oxide Dispersion Strengthened 18Cr Ferritic Steel

    NASA Astrophysics Data System (ADS)

    Nagini, M.; Vijay, R.; Rajulapati, Koteswararao V.; Rao, K. Bhanu Sankara; Ramakrishna, M.; Reddy, A. V.; Sundararajan, G.

    2016-06-01

    Pre-alloyed ferritic 18Cr steel (Fe-18Cr-2.3W-0.3Ti) powder was milled with and without nano-yttria in high-energy ball mill for varying times until steady-state is reached. The milled powders were consolidated by upset forging followed by hot extrusion. Microstructural changes were examined at all stages of processing (milling, upset forging, and extrusion). In milled powders, crystallite size decreases and hardness increases with increasing milling time reaching a steady-state beyond 5 hours. The size of Y2O3 particles in powders decreases with milling time and under steady-state milling conditions; the particles either dissolve in matrix or form atomic clusters. Upset forged sample consists of unrecrystallized grain structure with few pockets of fine recrystallized grains and dispersoids of 2 to 4 nm. In extruded and annealed rods, the particles are of cuboidal Y2Ti2O7 at all sizes and their size decreased from 15 nm to 5 nm along with significant increase in number density. The oxide particles in ODS6 are of cuboidal Y2Ti2O7 with diamond cubic crystal structure (Fd bar{3} m) having a lattice parameter of 10.1 Å and are semicoherent with the matrix. The hardness values of extruded and annealed samples predicted by linear summation model compare well with measured values.

  4. Fabrication of porous gelatin-chitosan microcarriers and modeling of process parameters via the RSM method.

    PubMed

    Karimian S A, Mohammad; Mashayekhan, Shohreh; Baniasadi, Hossein

    2016-07-01

    Porous gelatin-chitosan microcarriers (MCs) with the size of 350±50μm were fabricated with blends of different gelatin/chitosan (G/C) weight ratio using an electrospraying technique. Response surface methodology (RSM) was used to study the quantitative influence of process parameters, including blend ratio, voltage, and syringe pump flow rate, on MCs diameter and density. In the following, MCs of the same diameter and different G/C weight ratio (1, 2, and 3) were fabricated and their porosity and biocompatibility were investigated via SEM images and MTT assay, respectively. The results showed that mesenchymal stem cells (MSCs) could attach, proliferate, and spread on fabricated porous MCs during 7 days of culturing especially on those prepared with a G/C weight ratio of 1. Such porous gelatin-chitosan MCs with a G/C weight ratio of 1 may be considered as a promising candidate for injectable carriers supporting attachment and proliferation of MSCs. PMID:27037056

  5. The effect of process parameters on the internal quality of an aluminum die casting

    NASA Astrophysics Data System (ADS)

    Dewit, M. C. A. J.

    1986-01-01

    The influence of process parameters on the porosity of an aluminum die casting was investigated. Two types of die one of which had an interchangeable gate and two alloys, AlSi8Cu3 and AlSi7, were used. During the solidification phase of a die casting, air entrapment can occur; the air remains in the die casting under high pressure after solidification. The Rayleigh number which contains the velocity in the gate, the gate diameter, and the liquid metal surface tension, determines the air entrapment. It appears that there are two types of filling: solid front filling at low velocities, and standard spray filling at high velocities. With the former type, the castings contain no air, but the shrinkage is concentrated in big holes; with the latter type the castings contain much air, and the shrinkage is distributed over fine holes. The first phase velocity has no significant influence on the porosity; a decrease of the third phase velocity increases the porosity. Variations of the changeover point between the first and second phase have little influence.

  6. Optimization of process parameters for the production of spray dried Ber (Ziziphus jujube L.) powder.

    PubMed

    Singh, V K; Pandey, Sheela; Pare, Akash; Singh, R B

    2014-12-01

    The study covers effect of operating variables of spray dryer i.e. inlet temperature (170, 180, 190, 200 and 210 °C,), aspirator blower capacity (40, 50, 60, 70 and 80 %) and feed pump capacity (9, 12, 15, 18, and 21 %) and processing parameters of feed i.e. total soluble solid (TSS) of feed (7.5 %) and encapsulating material, maltodextrin (4, 6, 8, 10, and 12 %), aerosil (1.0 %), citric acid (0.25 %) upon the physical properties (colour, packed density and hygroscopicity) of powder were observed. After complete evaluation and analysis of all the attributes for physical properties i.e. colour, packed density (0.45 g/cc) and hygroscopicity (0.17 g/g dry matter), it was concluded that best quality of Ber powder were obtained at inlet air temperature 190 °C, aspirator blower capacity 60 %, feed pump capacity 15 %, encapsulating material 8 %. PMID:25477666

  7. Influence of ion source configuration and its operation parameters on the target sputtering and implantation process

    SciTech Connect

    Shalnov, K. V.; Kukhta, V. R.; Uemura, K.; Ito, Y.

    2012-06-15

    In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to {alpha}-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N{sub 2}-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling.

  8. Prolonged laser ablation effects of YBCO ceramic targets during thin film deposition: Influence of processing parameters

    NASA Astrophysics Data System (ADS)

    Tomov, R.; Tsaneva, V.; Tsanev, V.; Ouzounov, D.

    1996-12-01

    Cumulative laser irradiation during high-Tc superconducting thin film pulsed laser deposition (PLD) may have a detrimental effect on film characteristics. Initial decrease of deposition rate and gradual shift of the center of the deposited material spot towards the incoming laser beam were registered on cold glass substrates. Their absorbance was used for evaluation of the film thickness distribution over the substrate area. At the initial stage, two components of the spot could be distinguished along its short axis: central (˜cosn θ, n≫1) and peripherial (˜cos θ), while with cumulative irradiation the thickness followed an overall cosm θ (mprocessing parameters — laser fluence and oxygen environment. The results can be consistently explained suggesting the existence of an additional effective ablation threshold imposed by the modified surface relief.

  9. School Site Staff Development: Structures and Processes.

    ERIC Educational Resources Information Center

    Solo, Leonard J.

    1985-01-01

    Analyzes the importance of staff development (broadly defined as anything that enables teachers to learn) and considers different development structures. Describes the role and duties of staff developer at a Cambridge, Massachusetts, elementary school as well as its "teacher teams," groups of instructors who meet monthly to discuss issues…

  10. Development and characterization of a cell culture manufacturing process using quality by design (QbD) principles.

    PubMed

    Marasco, Daniel M; Gao, Jinxin; Griffiths, Kristi; Froggatt, Christopher; Wang, Tongtong; Wei, Gan

    2014-01-01

    The principles of quality by design (QbD) have been applied in cell culture manufacturing process development and characterization in the biotech industry. Here we share our approach and practice in developing and characterizing a cell culture manufacturing process using QbD principles for establishing a process control strategy. Process development and characterization start with critical quality attribute identification, followed by process parameter and incoming raw material risk assessment, design of experiment, and process parameter classification, and conclude with a design space construction. Finally, a rational process control strategy is established and documented. PMID:23828505

  11. Oil shale fines process developments in Brazil

    SciTech Connect

    Lisboa, A.C.; Nowicki, R.E. ); Piper, E.M. )

    1989-01-01

    The Petrobras oil shale retorting process, utilizes the particle range of +1/4 inch - 3 1/2 inches. The UPI plant in Sao Mateus do Sul has over 106,000 hours of operation, has processed over 6,200,000 metric tons of shale and has produced almost 3,000,000 barrels of shale oil. However, the nature of the raw oil shale is such that the amount of shale less than 1/4 inch that is mined and crushed and returned to the mine site is about 20 percent, thereby, increasing the cost of oil produced by a substantial number. Petrobras has investigated several systems to process the fines that are not handled by the 65 MTPH UPI plant and the 260 MTPH commercial plant. This paper provides an updated status of each of these processes in regard to the tests performed, potential contributions to an integrated use of the oil shale mine, and future considerations.

  12. Development of hybrid fluid jet/float polishing process

    NASA Astrophysics Data System (ADS)

    Beaucamp, Anthony T. H.; Namba, Yoshiharu; Freeman, Richard R.

    2013-09-01

    On one hand, the "float polishing" process consists of a tin lap having many concentric grooves, cut from a flat by single point diamond turning. This lap is rotated above a hydrostatic bearing spindle of high rigidity, damping and rotational accuracy. The optical surface thus floats above a thin layer of abrasive particles. But whilst surface texture can be smoothed to ~0.1nm rms (as measured by atomic force microscopy), this process can only be used on flat surfaces. On the other hand, the CNC "fluid jet polishing" process consists of pumping a mixture of water and abrasive particles to a converging nozzle, thus generating a polishing spot that can be moved along a tool path with tight track spacing. But whilst tool path feed can be moderated to ultra-precisely correct form error on freeform optical surfaces, surface finish improvement is generally limited to ~1.5nm rms (with fine abrasives). This paper reports on the development of a novel finishing method, that combines the advantages of "fluid jet polishing" (i.e. freeform corrective capability) with "float polishing" (i.e. super-smooth surface finish of 0.1nm rms or less). To come up with this new "hybrid" method, computational fluid dynamic modeling of both processes in COMSOL is being used to characterize abrasion conditions and adapt the process parameters of experimental fluid jet polishing equipment, including: (1) geometrical shape of nozzle, (2) position relative to the surface, (3) control of inlet pressure. This new process is aimed at finishing of next generation X-Ray / Gamma Ray focusing optics.

  13. Methodology development for the sustainability process assessment of sheet metal forming of complex-shaped products

    NASA Astrophysics Data System (ADS)

    Pankratov, D. L.; Kashapova, L. R.

    2015-06-01

    A methodology was developed for automated assessment of the reliability of the process of sheet metal forming process to reduce the defects in complex components manufacture. The article identifies the range of allowable values of the stamp parameters to obtain defect-free punching of spars trucks.

  14. Validation of cresis synthetic aperture radar processor and optimal processing parameters

    NASA Astrophysics Data System (ADS)

    Smith, Logan Sanders

    Sounding the ice sheets of Greenland and Antarctica is a vital component in determining the effect of global warming on sea level rise. Of particular importance are measurements of the bedrock topography of the outlet glaciers that transport ice from the ice sheet's interior to the margin where it calves into icebergs, contributing to sea level rise. These outlet glaciers are difficult to sound due to crevassing caused by the relatively fast movement of the ice in the glacial channel and higher signal attenuation caused by warmer ice. The Center for Remote Sensing of Ice Sheets (CReSIS) uses multi-channel airborne radars which employ methods for achieving better resolution and signal-to-noise ratio (SNR) to better sound outlet glaciers. Synthetic aperture radar (SAR) techniques are used in the along-track dimension, pulse compression in the range dimension, and an antenna array in the cross-track dimension. CReSIS has developed the CReSIS SAR processor (CSARP) to effectively and efficiently process the data collected by these radars in each dimension. To validate the performance of this processor a SAR simulator was developed with the functionality to test the implementation of the processing algorithms in CSARP. In addition to the implementation of this simulator for validation of processing the data in the along-track, cross-track and range dimensions, there are a number of data-dependent processing steps that can affect the quality of the final data product. CSARP was tested with an ideal simulated point target in white Gaussian noise. The SNR change achieved by range compression, azimuth compression, array combination with and without matched filtering, and lever arm application were all within .2 dB of the theoretical expectation. Channel equalization, when paired with noise-based matched filtering, provided 1-2 dB of gain on average but significantly less than the expected gain. Extending the SAR aperture length to sound bedrock will improve the along

  15. Inverse parameter determination in the development of an optimized lithium iron phosphate - Graphite battery discharge model

    NASA Astrophysics Data System (ADS)

    Maheshwari, Arpit; Dumitrescu, Mihaela Aneta; Destro, Matteo; Santarelli, Massimo

    2016-03-01

    Battery models are riddled with incongruous values of parameters considered for validation. In this work, thermally coupled electrochemical model of the pouch is developed and discharge tests on a LiFePO4 pouch cell at different discharge rates are used to optimize the LiFePO4 battery model by determining parameters for which there is no consensus in literature. A discussion on parameter determination, selection and comparison with literature values has been made. The electrochemical model is a P2D model, while the thermal model considers heat transfer in 3D. It is seen that even with no phase change considered for LiFePO4 electrode, the model is able to simulate the discharge curves over a wide range of discharge rates with a single set of parameters provided a dependency of the radius of the LiFePO4 electrode on discharge rate. The approach of using a current dependent radius is shown to be equivalent to using a current dependent diffusion coefficient. Both these modelling approaches are a representation of the particle size distribution in the electrode. Additionally, the model has been thermally validated, which increases the confidence level in the selection of values of parameters.

  16. Development of temporal and distance parameters of gait in normal children.

    PubMed

    Hillman, Susan J; Stansfield, Benedict W; Richardson, Alison M; Robb, James E

    2009-01-01

    Temporal and distance parameters of 33 normal children were obtained from instrumented gait analysis prospectively over five consecutive years. The parameters were normalised to minimise the confounding effects of increasing height and leg length. Rank correlations were performed on normalised speed, normalised stride length, normalised cadence and normalised walk ratio across consecutive pairs of years to examine the ranking of these parameters for an individual child over time. Consistent trends of increasing rank correlation were observed in normalised stride length and normalised walk ratio suggesting that individual children were continuing to adjust these gait parameters towards their own characteristic position within the normal range. Consistent trends were not observed in the rank correlations for normalised speed and normalised cadence. These findings support the concept that individual children predominantly adjusted their cadence to effect changes in speed, while the development of stride length was dictated by other factors specific to the individual child. Rank correlation coefficients for walk ratio between consecutive years increased from the ages of 7-11 years of age and hence walk ratio appears be a feature of gait that matures beyond the age of 7 years. This accords with the proposal that it is an invariant parameter for an individual. PMID:18701291

  17. Applying Expert System on the Development of a Robust Model for Groundwater Parameter Identification

    NASA Astrophysics Data System (ADS)

    Hsu, K.; Chang, L.; Jung, C.; Huang, C.; Chen, J.; Tsai, P. J.; Chen, Y.; Chang, P.

    2011-12-01

    Conventional groundwater parameter identification modeling based on optimization, such as UCODE, has difficulty converging to a global optimum in a high dimension situation. To avoid this convergence problem, this study integrates a rule-based expert system and a groundwater simulation model, MODFLOW 2000, to develop a robust methodology for groundwater parameter identification. Because the expert system requires calibration rules to identify parameters, users can flexibly add new rules or modify existing rules with this proposed methodology. Therefore, the proposed methodology can adapt for new parameter identification problems easily. We apply this proposed methodology to a real case study of Choshuihsi Alluvial Fan which is located at the central Taiwan. To test the robustness for high dimension problems, the proposed methodology is applied to calibrate the net recharge rates in a transient simulation in the study area. The result is compared with the calibration results obtained from UCODE. The results show that the initial guess dramatically effects the convergency of the optimization using UCODE, but our proposed methodology is very robust for achieving the convergence requirements of output error criteria for high dimensional problems. These results presented the robustness and the applicability of the proposed methodology for high dimensional groundwater parameter identification problems.

  18. IMPROVING INDUSTRIAL WASTEWATER TREATMENT PROCESS RELIABILITY TO ENHANCE SUSTAINABLE DEVELOPMENT

    EPA Science Inventory

    Sustainable development includes the recovery of resources from industrial manufacturing processes. One valuable resource that can often be purified and reused is process wastewater. Typically, pollutants are removed from process wastewater using physical, chemical, and biologica...

  19. Laboratory Activities for Developing Process Skills.

    ERIC Educational Resources Information Center

    Institute for Services to Education, Inc., Washington, DC.

    This workbook contains laboratory exercises designed for use in a college introductory biology course. Each exercise helps the student develop a basic science skill. The exercises are arranged in a hierarchical sequence suggesting the scientific method. Each skill facilitates the development of succeeding ones. Activities include Use of the…

  20. Development of a solvent processed insensitive propellant

    NASA Technical Reports Server (NTRS)

    Trask, R.; Costa, E.; Beardell, A. J.

    1980-01-01

    Two types of low vulnerability propellants are studied which are distinguished by whether the binder is a rubber, such as polyurethane or CTBN, or a plasticizable polymer such as ethyl cellulose or cellulose acetate. The former propellants are made by a partial cure extrusion process while the latter are made by the conventional solvent process. Emphasis is given to a cellulose binder (plasticizer) RDX composition. The type of binder used, the particle size of the RDX and the presence of small quantities of nitrocellulose in the solvent processed compositions have important influences on the mechanical and combustion characteristics of the propellant. The low temperature combustion is of particular concern because of potential breakup of the grains that can lead to instability.

  1. Development of infrared staking process for an automotive part

    NASA Astrophysics Data System (ADS)

    Park, H. S.; Nguyen, T. T.

    2015-11-01

    Staking plastic is a new technology that used infrared light as the energy sources in order to assembly the heated plastic parts. In this work, the proposed method coupling between Finite Element Method (FEM), Response Surface Method (RSM), and Genetic Algorithm (GA) is employed to simulate and optimize the staking plastic process. An automotive part, namely Door Trim with polypropylene (PP) material is implemented by using the developed technology. The effects of three key process parameters, such as heating time, cooling time, and air flow rate on the mechanical behavior of the joint has been investigated. The simulation procedure based on DEFORM-3D multi-operation is conducted to integrate sub-process and obtain the numerical results. The optimum values, including heating time, cooling time, and air flow rate are 14 second, 14 second, and 60 (ft3/h), respectively. The optimizing results indicated that heating time is more contributed to the tensile force, following by cooling time and air flow rate. The correlation between simulation and experimental results indicates the effectiveness of the proposed method.

  2. How to Develop, Validate, and Compare Clinical Prediction Models Involving Radiological Parameters: Study Design and Statistical Methods.

    PubMed

    Han, Kyunghwa; Song, Kijun; Choi, Byoung Wook

    2016-01-01

    Clinical prediction models are developed to calculate estimates of the probability of the presence/occurrence or future course of a particular prognostic or diagnostic outcome from multiple clinical or non-clinical parameters. Radiologic imaging techniques are being developed for accurate detection and early diagnosis of disease, which will eventually affect patient outcomes. Hence, results obtained by radiological means, especially diagnostic imaging, are frequently incorporated into a clinical prediction model as important predictive parameters, and the performance of the prediction model may improve in both diagnostic and prognostic settings. This article explains in a conceptual manner the overall process of developing and validating a clinical prediction model involving radiological parameters in relation to the study design and statistical methods. Collection of a raw dataset; selection of an appropriate statistical model; predictor selection; evaluation of model performance using a calibration plot, Hosmer-Lemeshow test and c-index; internal and external validation; comparison of different models using c-index, net reclassification improvement, and integrated discrimination improvement; and a method to create an easy-to-use prediction score system will be addressed. This article may serve as a practical methodological reference for clinical researchers. PMID:27134523

  3. How to Develop, Validate, and Compare Clinical Prediction Models Involving Radiological Parameters: Study Design and Statistical Methods

    PubMed Central

    Han, Kyunghwa; Choi, Byoung Wook

    2016-01-01

    Clinical prediction models are developed to calculate estimates of the probability of the presence/occurrence or future course of a particular prognostic or diagnostic outcome from multiple clinical or non-clinical parameters. Radiologic imaging techniques are being developed for accurate detection and early diagnosis of disease, which will eventually affect patient outcomes. Hence, results obtained by radiological means, especially diagnostic imaging, are frequently incorporated into a clinical prediction model as important predictive parameters, and the performance of the prediction model may improve in both diagnostic and prognostic settings. This article explains in a conceptual manner the overall process of developing and validating a clinical prediction model involving radiological parameters in relation to the study design and statistical methods. Collection of a raw dataset; selection of an appropriate statistical model; predictor selection; evaluation of model performance using a calibration plot, Hosmer-Lemeshow test and c-index; internal and external validation; comparison of different models using c-index, net reclassification improvement, and integrated discrimination improvement; and a method to create an easy-to-use prediction score system will be addressed. This article may serve as a practical methodological reference for clinical researchers. PMID:27134523

  4. Do fattening process and biological parameters affect the accumulation of metals in Atlantic bluefin tuna?

    PubMed

    Milatou, Niki; Dassenakis, Manos; Megalofonou, Persefoni

    2015-01-01

    The objective of this study was to determine the current levels of heavy metals and trace elements in Atlantic bluefin tuna muscle tissues and how they are influenced by the fattening process and various life history parameters to ascertain whether the concentrations in muscle tissue exceed the maximum levels defined by the European Commission Decision and to evaluate the health risk posed by fish consumption. A total of 20 bluefin tuna reared in sea cages, ranging from 160 to 295 cm in length and from 80 to 540 kg in weight, were sampled from a bluefin tuna farm in the Ionian Sea. The condition factor K of each specimen was calculated and their age was estimated. Heavy metal and trace element (Hg, Zn, Fe and Cu) contents were determined in muscle tissue using cold vapour atomic absorption spectrometry and flame and graphite furnace atomic absorption spectrometry. The total Hg concentrations ranged from 0.28 to 1.28 mg kg(-1) w/w, Zn from 5.81 to 76.37 mg kg(-1) w/w, Fe from 12.14 to 39.58 mg kg(-1) w/w, and Cu from 0.36 to 0.94 mg kg(-1) w/w. Only 5% of the muscle samples of tuna contained Hg above the maximum level laid down by the European Commission Decision. Moreover, 15% of the muscle samples contained Zn above the maximum level, while Fe and Cu concentrations were within the acceptable tolerable guideline values. The reared bluefin tuna had lower concentrations of Hg than the wild ones from the Mediterranean Sea. Hg and Fe concentrations showed a positive relationship with size and age of bluefin tuna, whereas negative relationships were found for the concentrations of Zn and Cu. The estimated dietary intake values of the analysed metals were mostly below the derived guidelines. PMID:25906290

  5. Predicting trace organic compound attenuation with spectroscopic parameters in powdered activated carbon processes.

    PubMed

    Ziska, Austin D; Park, Minkyu; Anumol, Tarun; Snyder, Shane A

    2016-08-01

    The removal of trace organic compounds (TOrCs) is of growing interest in water research and society. Powdered activated carbon (PAC) has been proven to be an effective method of removal for TOrCs in water, with the degree of effectiveness depending on dosage, contact time, and activated carbon type. In this study, the attenuation of TOrCs in three different secondary wastewater effluents using four PAC materials was studied in order to elucidate the effectiveness and efficacy of PAC for TOrC removal. With the notable exception of hydrochlorothiazide, all 14 TOrC indicators tested in this study exhibited a positive correlation of removal rate with their log Dow values, demonstrating that the main adsorption mechanism was hydrophobic interaction. As a predictive model, the modified Chick-Watson model, often used for the prediction of microorganism inactivation by disinfectants, was applied. The applied model exhibited good predictive power for TOrC attenuation by PAC in wastewater. In addition, surrogate models based upon spectroscopic measurements including UV absorbance at 254 nm and total fluorescence were applied to predict TOrC removal by PAC. The surrogate model was found to provide an excellent prediction of TOrC attenuation for all combinations of water quality and PAC type included in this study. The success of spectrometric parameters as surrogates in predicting TOrC attenuation by PAC are particularly useful because of their potential application in real-time on-line sensor monitoring and process control at full-scale water treatment plants, which could lead to significantly reduced operator response times and PAC operational optimization. PMID:27174829

  6. Developing Evaluation Capacity through Process Use

    ERIC Educational Resources Information Center

    King, Jean A.

    2007-01-01

    This article discusses how to make process use an independent variable in evaluation practice: the purposeful means of building an organization's capacity to conduct and use evaluations in the long run. The goal of evaluation capacity building (ECB) is to strengthen and sustain effective program evaluation practices through a number of activities:…

  7. The Development of Face Processing in Autism

    ERIC Educational Resources Information Center

    Sasson, Noah J.

    2006-01-01

    Both behavioral and neuroimaging evidence indicate that individuals with autism demonstrate marked abnormalities in the processing of faces. These abnormalities are often explained as either the result of an innate impairment to specialized neural systems or as a secondary consequence of reduced levels of social interest. A review of the…

  8. Gully development processes in the Ethiopian Highlands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gully erosion is an important soil degradation process in a range of environments, causing considerable soil losses and producing large volumes of sediment. In Ethiopia, gully erosion is a major problem expanding at alarming rate and devastating cultivated and grazing lands. The objective of the stu...

  9. The Development of Symbol Processing Abilities.

    ERIC Educational Resources Information Center

    Farnham-Diggory, Sylvia

    Visual and auditory stimuli were presented to children to measure symbol processing abilities. Slides which required matching the similarities in two objects in a group of three were presented. At times the matching criteria varied between function, color, and form. Reaction time was quicker when matching by color than by function, which was…

  10. Optimization of Process Parameters and Kinetic Model of Enzymatic Extraction of Polyphenols from Lonicerae Flos

    PubMed Central

    Kong, Fansheng; Yu, Shujuan; Bi, Yongguang; Huang, Xiaojun; Huang, Mengqian

    2016-01-01

    Objective: To optimize and verify the cellulase extraction of polyphenols from honeysuckle and provide a reference for enzymatic extracting polyphenols from honeysuckle. Materials and Methods: The uniform design was used According to Fick's first law and kinetic model, fitting analysis of the dynamic process of enzymatic extracting polyphenols was conducted. Results: The optimum enzymatic extraction parameters for polyphenols from honeysuckle are found to be 80% (v/v) of alcohol, 35:1 (mL/g) of liquid-solid ratio, 80°C of extraction temperature, 8.5 of pH, 6.0 mg of enzyme levels, and 130 min of extraction time. Under the optimal conditions, the extraction rate of polyphenols was 3.03%. The kinetic experiments indicated kinetic equation had a good linear relationship with t even under the conditions of different levels of enzyme and temperature, which means fitting curve tallies well with the experimental values. Conclusion: The results of quantification showed that the results provide a reference for enzymatic extracting polyphenols from honeysuckle. SUMMARY Lonicerae flos (Lonicera japonica Thunb.) is a material of traditional Chinese medicine and healthy drinks, of which active compounds mainly is polyphenols. At present, plant polyphenols are the hotspots centents of food, cosmetic and medicine, because it has strong bioactivity. Several traditional methods are available for the extraction of plant polyphenols including impregnation, solvent extraction, ultrasonic extraction, hot-water extraction, alkaline dilute alcohol or alkaline water extraction, microwave extraction and Supercritical CO2 extraction. But now, an increasing number of research on using cellulase to extract active ingredients from plants. Enzymatic method is widely used for enzyme have excellent properties of high reaction efficiency and specificity, moderate reaction conditions, shorter extraction time and easier to control, less damage to the active ingredient. At present, the enzymatic

  11. Computational Tools for Accelerating Carbon Capture Process Development

    SciTech Connect

    Miller, David; Sahinidis, N V; Cozad, A; Lee, A; Kim, H; Morinelly, J; Eslick, J; Yuan, Z

    2013-06-04

    This presentation reports development of advanced computational tools to accelerate next generation technology development. These tools are to develop an optimized process using rigorous models. They include: Process Models; Simulation-Based Optimization; Optimized Process; Uncertainty Quantification; Algebraic Surrogate Models; and Superstructure Optimization (Determine Configuration).

  12. USING GREEN CHEMISTRY TO INFLUENCE PROCESS DEVELOPMENT

    EPA Science Inventory

    The twelve principles of green chemistry by Anastas and Warner provide the researcher with a foundation or pathway which allows opportunities to incorporate greenness into an existing reaction or when developing alternative technologies. The twelve additional principles of green ...

  13. The combined effect of wet granulation process parameters and dried granule moisture content on tablet quality attributes.

    PubMed

    Gabbott, Ian P; Al Husban, Farhan; Reynolds, Gavin K

    2016-09-01

    A pharmaceutical compound was used to study the effect of batch wet granulation process parameters in combination with the residual moisture content remaining after drying on granule and tablet quality attributes. The effect of three batch wet granulation process parameters was evaluated using a multivariate experimental design, with a novel constrained design space. Batches were characterised for moisture content, granule density, crushing strength, porosity, disintegration time and dissolution. Mechanisms of the effect of the process parameters on the granule and tablet quality attributes are proposed. Water quantity added during granulation showed a significant effect on granule density and tablet dissolution rate. Mixing time showed a significant effect on tablet crushing strength, and mixing speed showed a significant effect on the distribution of tablet crushing strengths obtained. The residual moisture content remaining after granule drying showed a significant effect on tablet crushing strength. The effect of moisture on tablet tensile strength has been reported before, but not in combination with granulation parameters and granule properties, and the impact on tablet dissolution was not assessed. Correlations between the energy input during granulation, the density of granules produced, and the quality attributes of the final tablets were also identified. Understanding the impact of the granulation and drying process parameters on granule and tablet properties provides a basis for process optimisation and scaling. PMID:27016211

  14. Development of spiral density waves and evaluation of their parameters: a computer experiment

    SciTech Connect

    Grivnev, E.M.

    1985-07-01

    Numerical experiments with a disk of N = 250 interacting test-particles show that the velocity field does manifest development of the spiral density waves predicted by the Lin theory. The parameters of these simulated waves are evaluated in a nonlinear treatment. Similar N-body computer models can be employed to analyze the spiral structure in loosely wound galaxies such as NGC 3310 whose underlying equilibrium state is strongly perturbed.

  15. Identifying hazard parameter to develop quantitative and dynamic hazard map of an active volcano in Indonesia

    NASA Astrophysics Data System (ADS)

    Suminar, Wulan; Saepuloh, Asep; Meilano, Irwan

    2016-05-01

    Analysis of hazard assessment to active volcanoes is crucial for risk management. The hazard map of volcano provides information to decision makers and communities before, during, and after volcanic crisis. The rapid and accurate hazard assessment, especially to an active volcano is necessary to be developed for better mitigation on the time of volcanic crises in Indonesia. In this paper, we identified the hazard parameters to develop quantitative and dynamic hazard map of an active volcano. The Guntur volcano in Garut Region, West Java, Indonesia was selected as study area due population are resided adjacent to active volcanoes. The development of infrastructures, especially related to tourism at the eastern flank from the Summit, are growing rapidly. The remote sensing and field investigation approaches were used to obtain hazard parameters spatially. We developed a quantitative and dynamic algorithm to map spatially hazard potential of volcano based on index overlay technique. There were identified five volcano hazard parameters based on Landsat 8 and ASTER imageries: volcanic products including pyroclastic fallout, pyroclastic flows, lava and lahar, slope topography, surface brightness temperature, and vegetation density. Following this proposed technique, the hazard parameters were extracted, indexed, and calculated to produce spatial hazard values at and around Guntur Volcano. Based on this method, the hazard potential of low vegetation density is higher than high vegetation density. Furthermore, the slope topography, surface brightness temperature, and fragmental volcanic product such as pyroclastics influenced to the spatial hazard value significantly. Further study to this proposed approach will be aimed for effective and efficient analyses of volcano risk assessment.

  16. Developments in pharmacists' disciplinary processes and outcomes.

    PubMed

    Hattingh, Laetitia; Smith, Nerida; Searle, Judy; Forrester, Kim

    2008-08-01

    Pharmacy disciplinary processes and outcomes protect consumers by deterring pharmacists from unacceptable practices and maintaining the reputation and standing of the pharmacy profession. It is important that pharmacists are informed of disciplinary processes and outcomes in order to predict what is regarded as unacceptable behaviour and the potential consequences thereof. Disciplinary procedures and outcomes also play an important role in maintaining public trust in the pharmacy profession and it is therefore important that the public has confidence in the disciplinary structure. The outcomes of pharmacy disciplinary cases that reflect the patient care role of pharmacists are particularly important in helping to determine pharmacists' changed professional responsibility and potential legal liability in the provision of these patient care services. PMID:18807799

  17. Multi-objective optimization of process parameters in Electro-Discharge Diamond Face Grinding based on ANN-NSGA-II hybrid technique

    NASA Astrophysics Data System (ADS)

    Yadav, Ravindra Nath; Yadava, Vinod; Singh, G. K.

    2013-09-01

    The effective study of hybrid machining processes (HMPs), in terms of modeling and optimization has always been a challenge to the researchers. The combined approach of Artificial Neural Network (ANN) and Non-Dominated Sorting Genetic Algorithm-II (NSGA-II) has attracted attention of researchers for modeling and optimization of the complex machining processes. In this paper, a hybrid machining process of Electrical Discharge Face Grinding (EDFG) and Diamond Face Grinding (DFG) named as Electrical Discharge Diamond face Grinding (EDDFG) have been studied using a hybrid methodology of ANN-NSGA-II. In this study, ANN has been used for modeling while NSGA-II is used to optimize the control parameters of the EDDFG process. For observations of input-output relations, the experiments were conducted on a self developed face grinding setup, which is attached with the ram of EDM machine. During experimentation, the wheel speed, pulse current, pulse on-time and duty factor are taken as input parameters while output parameters are material removal rate (MRR) and average surface roughness ( R a). The results have shown that the developed ANN model is capable to predict the output responses within the acceptable limit for a given set of input parameters. It has also been found that hybrid approach of ANN-NSGAII gives a set of optimal solutions for getting appropriate value of outputs with multiple objectives.

  18. Modeling the X-Ray Process, and X-Ray Flaw Size Parameter for POD Studies

    NASA Technical Reports Server (NTRS)

    Khoshti, Ajay

    2014-01-01

    Nondestructive evaluation (NDE) method reliability can be determined by a statistical flaw detection study called probability of detection (POD) study. In many instances the NDE flaw detectability is given as a flaw size such as crack length. The flaw is either a crack or behaving like a crack in terms of affecting the structural integrity of the material. An alternate approach is to use a more complex flaw size parameter. The X-ray flaw size parameter, given here, takes into account many setup and geometric factors. The flaw size parameter relates to X-ray image contrast and is intended to have a monotonic correlation with the POD. Some factors such as set-up parameters including X-ray energy, exposure, detector sensitivity, and material type that are not accounted for in the flaw size parameter may be accounted for in the technique calibration and controlled to meet certain quality requirements. The proposed flaw size parameter and the computer application described here give an alternate approach to conduct the POD studies. Results of the POD study can be applied to reliably detect small flaws through better assessment of effect of interaction between various geometric parameters on the flaw detectability. Moreover, a contrast simulation algorithm for a simple part-source-detector geometry using calibration data is also provided for the POD estimation.

  19. Modeling the X-ray Process, and X-ray Flaw Size Parameter for POD Studies

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2014-01-01

    Nondestructive evaluation (NDE) method reliability can be determined by a statistical flaw detection study called probability of detection (POD) study. In many instances, the NDE flaw detectability is given as a flaw size such as crack length. The flaw is either a crack or behaving like a crack in terms of affecting the structural integrity of the material. An alternate approach is to use a more complex flaw size parameter. The X-ray flaw size parameter, given here, takes into account many setup and geometric factors. The flaw size parameter relates to X-ray image contrast and is intended to have a monotonic correlation with the POD. Some factors such as set-up parameters, including X-ray energy, exposure, detector sensitivity, and material type that are not accounted for in the flaw size parameter may be accounted for in the technique calibration and controlled to meet certain quality requirements. The proposed flaw size parameter and the computer application described here give an alternate approach to conduct the POD studies. Results of the POD study can be applied to reliably detect small flaws through better assessment of effect of interaction between various geometric parameters on the flaw detectability. Moreover, a contrast simulation algorithm for a simple part-source-detector geometry using calibration data is also provided for the POD estimation.

  20. Development of enhanced sulfur rejection processes

    SciTech Connect

    Yoon, R.H.; Luttrell, G.; Adel, G.; Richardson, P.E.

    1993-03-23

    Research at Virginia Tech led to two complementary concepts for improving the removal of inorganic sulfur from much of the Eastern US coals. One controls the surface properties of coal pyrite (FeS[sub 2]) by electrochemical-.potential control, referred to as the Electrochemically Enhanced Sulfur Rejection (EESR) Process: The second controls the flotation of middlings, i.e., particles composed of pyrite with coal inclusions by using polymeric reagents to react with pyrite and convert the middlings to hydrophilic particles, and is termed the Polymer Enhanced Sulfur Rejection (PESR) Process. These new concepts are based on recent research establishing the two main reasons why flotation fails to remove more than about 50% of the pyritic sulfur from coal: superficial oxidization of liberated pyrite to form polysulfide oxidation products so that a part of the liberated pyrite floats with the coal; and hydrophobic coal inclusions in the middlings dominating their flotation so that the middlings also float with the coal. These new pyritic-sulfur rejection processes do not require significant modifications of existing coal preparation facilities, enhancing their adoptability by the coal industry. It is believed that they can be used simultaneously to achieve both free pyrite and locked pyrite rejection.

  1. Nondestructive evaluation development for process control

    SciTech Connect

    Ellingson, W.A.; Holloway, D.L.; Sivers, E.A. ); Ling, J. . Inst. for Ceramics); Pollinger, J.P.; Yeh, H.C. . Garrett Ceramic Components Div.)

    1991-01-01

    A joint project between Garrett Ceramic Components (GCC) of Allied Signal Aerospace Corporation and Argonne National Laboratory (ANL) is ongoing to evaluate nondestructive characterization (NDC) methods to detect and measure process-induced variations in ceramic materials. The process methods of current focus on slip-casting and injection molding and the NDC methods being evaluated are microfocus X-ray computed tomography (XCT) and nuclear magnetic resonance computed tomography (MRCT). As part of this work, SiC whisker reinforced Si{sub 3}N{sub 4} (GCC's GN-10 material) has been pressure slip-cast at two casting pressures, 15 and 40 psi; and at length/diameter ratios of 1.5, 2.5 and 3.0 with whisker contents of 20, 23, 27 and 30 wt %. Three-dimensional microfocus XCT has been used to study density variations in billets produced by different process conditions. Destructive measurement of density variation has been compared to the XCT measurements and correlations established. XCT has been shown to be able to detect <5% variations in as-cast density and these were destructively verified.

  2. Nondestructive evaluation development for process control

    SciTech Connect

    Ellingson, W.A.; Holloway, D.L.; Sivers, E.A.; Ling, J.; Pollinger, J.P.; Yeh, H.C.

    1991-12-31

    A joint project between Garrett Ceramic Components (GCC) of Allied Signal Aerospace Corporation and Argonne National Laboratory (ANL) is ongoing to evaluate nondestructive characterization (NDC) methods to detect and measure process-induced variations in ceramic materials. The process methods of current focus on slip-casting and injection molding and the NDC methods being evaluated are microfocus X-ray computed tomography (XCT) and nuclear magnetic resonance computed tomography (MRCT). As part of this work, SiC whisker reinforced Si{sub 3}N{sub 4} (GCC`s GN-10 material) has been pressure slip-cast at two casting pressures, 15 and 40 psi; and at length/diameter ratios of 1.5, 2.5 and 3.0 with whisker contents of 20, 23, 27 and 30 wt %. Three-dimensional microfocus XCT has been used to study density variations in billets produced by different process conditions. Destructive measurement of density variation has been compared to the XCT measurements and correlations established. XCT has been shown to be able to detect <5% variations in as-cast density and these were destructively verified.

  3. Development of advanced techniques for rotorcraft state estimation and parameter identification

    NASA Technical Reports Server (NTRS)

    Hall, W. E., Jr.; Bohn, J. G.; Vincent, J. H.

    1980-01-01

    An integrated methodology for rotorcraft system identification consists of rotorcraft mathematical modeling, three distinct data processing steps, and a technique for designing inputs to improve the identifiability of the data. These elements are as follows: (1) a Kalman filter smoother algorithm which estimates states and sensor errors from error corrupted data. Gust time histories and statistics may also be estimated; (2) a model structure estimation algorithm for isolating a model which adequately explains the data; (3) a maximum likelihood algorithm for estimating the parameters and estimates for the variance of these estimates; and (4) an input design algorithm, based on a maximum likelihood approach, which provides inputs to improve the accuracy of parameter estimates. Each step is discussed with examples to both flight and simulated data cases.

  4. Rolling Process Modeling Report. Finite-Element Model Validation and Parametric Study on various Rolling Process parameters

    SciTech Connect

    Soulami, Ayoub; Lavender, Curt A.; Paxton, Dean M.; Burkes, Douglas

    2015-06-15

    Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum alloy plate-type fuel for high-performance research reactors in the United States. This work supports the U.S. Department of Energy National Nuclear Security Administration’s Office of Material Management and Minimization Reactor Conversion Program. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll-separating forces for various rolling mill geometries for PNNL, Babcock & Wilcox Co., Y-12 National Security Complex, Los Alamos National Laboratory, and Idaho National Laboratory. The model developed and presented in a previous report has been subjected to further validation study using new sets of experimental data generated from a rolling mill at PNNL. Simulation results of both hot rolling and cold rolling of uranium-10% molybdenum coupons have been compared with experimental results. The model was used to predict roll-separating forces at different temperatures and reductions for five rolling mills within the National Nuclear Security Administration Fuel Fabrication Capability project. This report also presents initial results of a finite-element model microstructure-based approach to study the surface roughness at the interface between zirconium and uranium-10% molybdenum.

  5. Development of a corn and soybean labeling procedure for use with profile parameter classification

    NASA Technical Reports Server (NTRS)

    Magness, E. R. (Principal Investigator)

    1982-01-01

    Some essential processes for the development of a green-number-based logic for identifying (labeling) crops in LANDSAT imagery are documented. The supporting data and subsequent conclusions that resulted from development of a specific labeling logic for corn and soybean crops in the United States are recorded.

  6. Optimization of Processing Parameters in ECM of Die Tool Steel Using Nanofluid by Multiobjective Genetic Algorithm

    PubMed Central

    Sathiyamoorthy, V.; Sekar, T.; Elango, N.

    2015-01-01

    Formation of spikes prevents achievement of the better material removal rate (MRR) and surface finish while using plain NaNO3 aqueous electrolyte in electrochemical machining (ECM) of die tool steel. Hence this research work attempts to minimize the formation of spikes in the selected workpiece of high carbon high chromium die tool steel using copper nanoparticles suspended in NaNO3 aqueous electrolyte, that is, nanofluid. The selected influencing parameters are applied voltage and electrolyte discharge rate with three levels and tool feed rate with four levels. Thirty-six experiments were designed using Design Expert 7.0 software and optimization was done using multiobjective genetic algorithm (MOGA). This tool identified the best possible combination for achieving the better MRR and surface roughness. The results reveal that voltage of 18 V, tool feed rate of 0.54 mm/min, and nanofluid discharge rate of 12 lit/min would be the optimum values in ECM of HCHCr die tool steel. For checking the optimality obtained from the MOGA in MATLAB software, the maximum MRR of 375.78277 mm3/min and respective surface roughness Ra of 2.339779 μm were predicted at applied voltage of 17.688986 V, tool feed rate of 0.5399705 mm/min, and nanofluid discharge rate of 11.998816 lit/min. Confirmatory tests showed that the actual performance at the optimum conditions was 361.214 mm3/min and 2.41 μm; the deviation from the predicted performance is less than 4% which proves the composite desirability of the developed models. PMID:26167538

  7. Optimization of Processing Parameters in ECM of Die Tool Steel Using Nanofluid by Multiobjective Genetic Algorithm.

    PubMed

    Sathiyamoorthy, V; Sekar, T; Elango, N

    2015-01-01

    Formation of spikes prevents achievement of the better material removal rate (MRR) and surface finish while using plain NaNO3 aqueous electrolyte in electrochemical machining (ECM) of die tool steel. Hence this research work attempts to minimize the formation of spikes in the selected workpiece of high carbon high chromium die tool steel using copper nanoparticles suspended in NaNO3 aqueous electrolyte, that is, nanofluid. The selected influencing parameters are applied voltage and electrolyte discharge rate with three levels and tool feed rate with four levels. Thirty-six experiments were designed using Design Expert 7.0 software and optimization was done using multiobjective genetic algorithm (MOGA). This tool identified the best possible combination for achieving the better MRR and surface roughness. The results reveal that voltage of 18 V, tool feed rate of 0.54 mm/min, and nanofluid discharge rate of 12 lit/min would be the optimum values in ECM of HCHCr die tool steel. For checking the optimality obtained from the MOGA in MATLAB software, the maximum MRR of 375.78277 mm(3)/min and respective surface roughness Ra of 2.339779 μm were predicted at applied voltage of 17.688986 V, tool feed rate of 0.5399705 mm/min, and nanofluid discharge rate of 11.998816 lit/min. Confirmatory tests showed that the actual performance at the optimum conditions was 361.214 mm(3)/min and 2.41 μm; the deviation from the predicted performance is less than 4% which proves the composite desirability of the developed models. PMID:26167538

  8. A physical parameter identification method of Lévy-driven vibratory systems based on multipower variation processes

    NASA Astrophysics Data System (ADS)

    Du, Xiu-Li; Lin, Jin-Guan; Liu, Guo-Xiang; Zhou, Xiu-Qing

    2015-05-01

    In this paper, we put forward a physical parameter identification method of Lévy-driven engineering structures. Based on the properties of the quadratic variation and multipower variation processes, the structural dynamic equation is decomposed into the Gaussian continuous-time autoregressive (CAR) equation and the pure jump-driven CAR equation. Both equations have the same unknown parameters as those included in the Lévy-driven system. The parameters of the Lévy-driven system are identified by the maximum likelihood estimation method of the Gaussian CAR system. The numerical results demonstrate that the method works well.

  9. Collection Development as a Social Process.

    ERIC Educational Resources Information Center

    Lee, Hur-Li

    2003-01-01

    This case study examines social influences in research libraries' collection development. It shows that individuals' ideologies and political agenda shape their impression of user needs and their decision making. The study also reveals how the institution's operating structures, campus politics of interdisciplinarity, personnel deployment, and…

  10. Group Process and Adolescent Leadership Development.

    ERIC Educational Resources Information Center

    Hohmann, Mary; And Others

    1982-01-01

    Describes an approach to leadership development which is particularly supportive of the needs of adolescents and reflective of a democratic style of leadership. It is an outgrowth of the High/Scope Summer Workshop for Teenagers, which helped young people acquire leadership skills through group membership and cooperation. (Author)

  11. Robot welding process control development task

    NASA Technical Reports Server (NTRS)

    Romine, Peter L.

    1992-01-01

    The completion of, and improvements made to, the software developed during 1990 for program maintenance on the PC and HEURIKON and transfer to the CYRO, and integration of the Rocketdyne vision software with the CYRO is documented. The new programs were used successfully by NASA, Rocketdyne, and UAH technicians and engineers to create, modify, upload, download, and control CYRO NC programs.

  12. Interrogating inclusive development in India's transition process.

    PubMed

    Chakrabarti, Anjan; Dhar, Anup

    2012-12-01

    This paper makes two related contributions. First, the dual economic structure underlying development is shown as producing a distinct conception of other comprising of a devalued third world which is foregrounded and world of the third which is excluded. This dyad of inclusion-exclusion of other is produced in relation to the centers of capitalism and modernism. The category of third world helps to displace the language-experience-logic-ethos of the other a la world of the third such that development works over and transforms world of the third, but via the trope of a devalued third world. We then use this framework to explore the relation of global capitalism with world of the third in the Indian context, a relation that is shown to be two fold. There is on one hand an attempt to dismantle world of the third as part of the development trope of overcoming the third world. On the other, through inclusive development, an attempt is made to directly intervene in the economy of world of the third so as to address the problems of income inequality and social exclusion, again under the trope of uplifting the devalued third world. PMID:23390797

  13. OSTA/ADS standards development process

    NASA Technical Reports Server (NTRS)

    Walton, B.

    1981-01-01

    A phased approach to data systems standards was developed. The standards survey, user requirements, methodology survey, and evaluation criteria were completed. Remaining to be done are data system planning interim standards, a concept for implementation of a core applications data service, a data systems policy definition, and full capability data services definition.

  14. Nutritional and engineering aspects of microbial process development.

    PubMed

    Masurekar, Prakash S

    2008-01-01

    Today we use many drugs produced by microorganisms. However, when these drugs were discovered it was found that the yields were low and a substantial effort had to be put in to develop commercially viable processes. A key part of this endeavor was the studies of the nutritional and the engineering parameters. In this chapter, the basic principles of optimizing the nutritional and engineering aspect of the production process are described with appropriate examples. It was found that two critical components of nutritional medium, carbon and nitrogen source regulated the synthesis of the compounds of interest. Rapidly utilizable carbon source such as glucose supported the growth but led to catabolite repression and alternative carbon sources or methods of addition had to be devised. Inorganic nitrogen sources led to undesirable changes in pH of the medium. Organic nitrogen sources could influence the yields positively or negatively and had to be chosen carefully. Essential nutrients like phosphates often inhibited the synthesis and its concentration had to be maintained below the inhibitory levels. On many occasions, trace nutrients like metal ions and vitamins were found to be critical for good production. Temperature and pH were important environmental variables and their optimum values had to be determined. The media were designed and optimized initially with 'one variable at a time' approach and later with experimental design based on statistics. The latter approach is preferred because it is economical, considers interactions between medium components and allows rapid optimization of the process. The engineering aspects like aeration, agitation, medium sterilization, heat transfer, process monitoring and control, become critical as the process is scaled-up to the production size. Aeration and agitation are probably the most important variables. In many processes dissolved oxygen concentration had to be maintained above a critical value to obtain the best yields

  15. Development of the NEXT Power Processing Unit

    NASA Technical Reports Server (NTRS)

    Phelps, Thomas K.; Wiseman, Steve; Komm, David S.; Bond, Thomas; Pinero, Luis R.

    2005-01-01

    Boeing Electron Dynamic Devices, Inc. (EDD) has designed and fabricated a breadboard version of a 6 kW power processing unit (PPU) for gridded ion thrusters. This breadboard PPU will be integrated with an engineering model 40 cm ion engine designed and tested at NASA Glenn. The results of our tests using resistive loads are reported in this paper. The PPU demonstrated efficiencies to date are higher than 95 percent for the beam supply and higher than 92 percent for the discharge supply at full power. Overall PPU efficiency is greater than 94 percent at full throttle settings.

  16. A Design of Experiment approach to predict product and process parameters for a spray dried influenza vaccine.

    PubMed

    Kanojia, Gaurav; Willems, Geert-Jan; Frijlink, Henderik W; Kersten, Gideon F A; Soema, Peter C; Amorij, Jean-Pierre

    2016-09-25

    Spray dried vaccine formulations might be an alternative to traditional lyophilized vaccines. Compared to lyophilization, spray drying is a fast and cheap process extensively used for drying biologicals. The current study provides an approach that utilizes Design of Experiments for spray drying process to stabilize whole inactivated influenza virus (WIV) vaccine. The approach included systematically screening and optimizing the spray drying process variables, determining the desired process parameters and predicting product quality parameters. The process parameters inlet air temperature, nozzle gas flow rate and feed flow rate and their effect on WIV vaccine powder characteristics such as particle size, residual moisture content (RMC) and powder yield were investigated. Vaccine powders with a broad range of physical characteristics (RMC 1.2-4.9%, particle size 2.4-8.5μm and powder yield 42-82%) were obtained. WIV showed no significant loss in antigenicity as revealed by hemagglutination test. Furthermore, descriptive models generated by DoE software could be used to determine and select (set) spray drying process parameter. This was used to generate a dried WIV powder with predefined (predicted) characteristics. Moreover, the spray dried vaccine powders retained their antigenic stability even after storage for 3 months at 60°C. The approach used here enabled the generation of a thermostable, antigenic WIV vaccine powder with desired physical characteristics that could be potentially used for pulmonary administration. PMID:27523619

  17. 21 CFR 861.20 - Summary of standards development process.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Summary of standards development process. 861.20... (CONTINUED) MEDICAL DEVICES PROCEDURES FOR PERFORMANCE STANDARDS DEVELOPMENT Procedures for Performance Standards Development and Publication § 861.20 Summary of standards development process. The procedure...

  18. The influence of melting process and parameters on the structure and homogeneity of titanium-tantalum alloys

    SciTech Connect

    Dunn, P.S.; Korzewka, D.; Garcia, F.; Damkroger, B.K.; Van Den Avyle, J.A.; Tissot, R.G.

    1995-12-31

    Alloys of titanium with refractory metals are attractive materials for applications requiring high temperature strength and corrosion resistance. However, the widely different characteristics of the component elements have made it difficult to produce sound, compositionally homogeneous ingots using traditional melting techniques. This is particularly critical because the compositional ranges spanned by the micro- and macrosegregation in theses systems can easily encompass a number of microconstituents which are detrimental to mechanical properties. This paper presents results of a study of plasma (PAM) and vacuum-arc (VAR) melting of a 60 wt% tantalum, 40 wt% titanium binary alloy. The structural and compositional homogeneity of both PAM consolidated + PAM remelted, and PAM consolidated + VAR remelted ingots were characterized and compared using optical and electron microscopy and x-ray fluorescence microanalysis. Additionally, the effect of melting parameter, including melt rate and magnetic stirring, was studied. Results indicate that PAM remelting achieves more complete dissolution of lie starting electrode, due to greater local superheat, than does VAR remelting. PAM remelting also produces a finer as-solidified grain structure, due to the smaller molten pool and lower local solidification times. Conversely, VAR remelting produces an ingot with a more uniform macrostructure, due to the more stable movement of the solidification interface and more uniform material feed rate. Based on these results, a three-step process of PAM consolidation, followed by a PAM intermediate melt and a VAR final melt, has been selected for further development of the alloy and processing sequence.

  19. Study on the estimation of the range parameter for SAR signal processing

    NASA Astrophysics Data System (ADS)

    Zhao, Yinghui; Yue, Xijuan; Han, Chunming

    2015-12-01

    Range is the key parameter for synthetic aperture radar imaging. The range parameter estimation using the relationship between the radar internal calibration signals and system signal is studied in this paper. The delay of the system signal is computed based on the delays of the three internal calibration signals recorded. Using the approach proposed, the standard deviation of the range delay of the radar system signal is about 0.1mm.

  20. Signal processing to evaluate parameters affecting SPE for multi-residue analysis of personal care products.

    PubMed

    Pietrogrande, Maria Chiara; Basaglia, Giulia; Dondi, Francesco

    2009-05-01

    This paper discusses the development of a comprehensive method for the simultaneous analysis of personal care products (PCPs) based on SPE and GC-MS. The method was developed on 29 target compounds to represent PCPs belonging to different chemical classes: surfactants in detergents (alkyl benzenes), fragrances in cosmetics (nitro and polycyclic musks), antioxidants and preservatives (phenols), plasticizers (phthalates) displaying a wide range of volatility, polarity, water solubility. In addition to the conventional C(18) stationary phase, a surface modified styrene divinylbenzene polymeric phase (Strata X SPE cartridge) has been investigated as suitable for the simultaneous extraction of several PCPs with polar and non-polar characteristics. For both sorbents different solvent compositions and eluting conditions were tested and compared in order to achieve high extraction efficiency for as many sample components as possible. Comparison of the behavior of the two cartridges reveals that, overall, Strata-X provides better efficiency with extraction recovery higher than 70% for most of the PCPs investigated. The best results were obtained under the following operative conditions: an evaporation temperature of 40 degrees C, elution on Strata-X cartridge using a volume of 15 mL of ethyl acetate (EA) as solvent and operating with slow flow rate (-10 KPa). In addition to the conventional method based on peak integration, a chemometric approach based on the computation of the experimental autocovariance function (EACVF(tot)) was applied to the complex GC-MS signal: the percentage recovery and information on peak abundance distribution can be evaluated for each procedure step. The PC-based signal processing proved very helpful in assisting the development of the analytical procedure, since it saves labor and time and increases result reliability in handling GC complex signals. PMID:19399858