Sample records for process control method

  1. Analytical method for promoting process capability of shock absorption steel.

    PubMed

    Sung, Wen-Pei; Shih, Ming-Hsiang; Chen, Kuen-Suan

    2003-01-01

    Mechanical properties and low cycle fatigue are two factors that must be considered in developing new type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure process yield and process centering; so this paper uses Taguchi loss function as basis to establish an evaluation method and the steps for assessing the quality of mechanical properties and process control of an iron and steel manufacturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.

  2. Modelling and control for laser based welding processes: modern methods of process control to improve quality of laser-based joining methods

    NASA Astrophysics Data System (ADS)

    Zäh, Ralf-Kilian; Mosbach, Benedikt; Hollwich, Jan; Faupel, Benedikt

    2017-02-01

    To ensure the competitiveness of manufacturing companies it is indispensable to optimize their manufacturing processes. Slight variations of process parameters and machine settings have only marginally effects on the product quality. Therefore, the largest possible editing window is required. Such parameters are, for example, the movement of the laser beam across the component for the laser keyhole welding. That`s why it is necessary to keep the formation of welding seams within specified limits. Therefore, the quality of laser welding processes is ensured, by using post-process methods, like ultrasonic inspection, or special in-process methods. These in-process systems only achieve a simple evaluation which shows whether the weld seam is acceptable or not. Furthermore, in-process systems use no feedback for changing the control variables such as speed of the laser or adjustment of laser power. In this paper the research group presents current results of the research field of Online Monitoring, Online Controlling and Model predictive controlling in laser welding processes to increase the product quality. To record the characteristics of the welding process, tested online methods are used during the process. Based on the measurement data, a state space model is ascertained, which includes all the control variables of the system. Depending on simulation tools the model predictive controller (MPC) is designed for the model and integrated into an NI-Real-Time-System.

  3. Autocorrelated process control: Geometric Brownian Motion approach versus Box-Jenkins approach

    NASA Astrophysics Data System (ADS)

    Salleh, R. M.; Zawawi, N. I.; Gan, Z. F.; Nor, M. E.

    2018-04-01

    Existing of autocorrelation will bring a significant effect on the performance and accuracy of process control if the problem does not handle carefully. When dealing with autocorrelated process, Box-Jenkins method will be preferred because of the popularity. However, the computation of Box-Jenkins method is too complicated and challenging which cause of time-consuming. Therefore, an alternative method which known as Geometric Brownian Motion (GBM) is introduced to monitor the autocorrelated process. One real case of furnace temperature data is conducted to compare the performance of Box-Jenkins and GBM methods in monitoring autocorrelation process. Both methods give the same results in terms of model accuracy and monitoring process control. Yet, GBM is superior compared to Box-Jenkins method due to its simplicity and practically with shorter computational time.

  4. 29 CFR 1910.1026 - Chromium (VI).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... resembling the processes, types of material, control methods, work practices, and environmental conditions in... resembling the processes, types of material, control methods, work practices, and environmental conditions in..., work practices, or control methods that may result in new or additional exposures to chromium (VI), or...

  5. 29 CFR 1910.1026 - Chromium (VI).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... resembling the processes, types of material, control methods, work practices, and environmental conditions in... resembling the processes, types of material, control methods, work practices, and environmental conditions in..., work practices, or control methods that may result in new or additional exposures to chromium (VI), or...

  6. Learning-based controller for biotechnology processing, and method of using

    DOEpatents

    Johnson, John A.; Stoner, Daphne L.; Larsen, Eric D.; Miller, Karen S.; Tolle, Charles R.

    2004-09-14

    The present invention relates to process control where some of the controllable parameters are difficult or impossible to characterize. The present invention relates to process control in biotechnology of such systems, but not limited to. Additionally, the present invention relates to process control in biotechnology minerals processing. In the inventive method, an application of the present invention manipulates a minerals bioprocess to find local exterma (maxima or minima) for selected output variables/process goals by using a learning-based controller for bioprocess oxidation of minerals during hydrometallurgical processing. The learning-based controller operates with or without human supervision and works to find processor optima without previously defined optima due to the non-characterized nature of the process being manipulated.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hohimer, J.P.

    The use of laser-based analytical methods in nuclear-fuel processing plants is considered. The species and locations for accountability, process control, and effluent control measurements in the Coprocessing, Thorex, and reference Purex fuel processing operations are identified and the conventional analytical methods used for these measurements are summarized. The laser analytical methods based upon Raman, absorption, fluorescence, and nonlinear spectroscopy are reviewed and evaluated for their use in fuel processing plants. After a comparison of the capabilities of the laser-based and conventional analytical methods, the promising areas of application of the laser-based methods in fuel processing plants are identified.

  8. Innovative application of the moisture analyzer for determination of dry mass content of processed cheese

    NASA Astrophysics Data System (ADS)

    Kowalska, Małgorzata; Janas, Sławomir; Woźniak, Magdalena

    2018-04-01

    The aim of this work was the presentation of an alternative method of determination of the total dry mass content in processed cheese. The authors claim that the presented method can be used in industry's quality control laboratories for routine testing and for quick in-process control. For the test purposes both reference method of determination of dry mass in processed cheese and moisture analyzer method were used. The tests were carried out for three different kinds of processed cheese. In accordance with the reference method, the sample was placed on a layer of silica sand and dried at the temperature of 102 °C for about 4 h. The moisture analyzer test required method validation, with regard to drying temperature range and mass of the analyzed sample. Optimum drying temperature of 110 °C was determined experimentally. For Hochland cream processed cheese sample, the total dry mass content, obtained using the reference method, was 38.92%, whereas using the moisture analyzer method, it was 38.74%. An average analysis time in case of the moisture analyzer method was 9 min. For the sample of processed cheese with tomatoes, the reference method result was 40.37%, and the alternative method result was 40.67%. For the sample of cream processed cheese with garlic the reference method gave value of 36.88%, and the alternative method, of 37.02%. An average time of those determinations was 16 min. Obtained results confirmed that use of moisture analyzer is effective. Compliant values of dry mass content were obtained for both of the used methods. According to the authors, the fact that the measurement took incomparably less time for moisture analyzer method, is a key criterion of in-process control and final quality control method selection.

  9. The application of hazard analysis and critical control points and risk management in the preparation of anti-cancer drugs.

    PubMed

    Bonan, Brigitte; Martelli, Nicolas; Berhoune, Malik; Maestroni, Marie-Laure; Havard, Laurent; Prognon, Patrice

    2009-02-01

    To apply the Hazard analysis and Critical Control Points method to the preparation of anti-cancer drugs. To identify critical control points in our cancer chemotherapy process and to propose control measures and corrective actions to manage these processes. The Hazard Analysis and Critical Control Points application began in January 2004 in our centralized chemotherapy compounding unit. From October 2004 to August 2005, monitoring of the process nonconformities was performed to assess the method. According to the Hazard Analysis and Critical Control Points method, a multidisciplinary team was formed to describe and assess the cancer chemotherapy process. This team listed all of the critical points and calculated their risk indexes according to their frequency of occurrence, their severity and their detectability. The team defined monitoring, control measures and corrective actions for each identified risk. Finally, over a 10-month period, pharmacists reported each non-conformity of the process in a follow-up document. Our team described 11 steps in the cancer chemotherapy process. The team identified 39 critical control points, including 11 of higher importance with a high-risk index. Over 10 months, 16,647 preparations were performed; 1225 nonconformities were reported during this same period. The Hazard Analysis and Critical Control Points method is relevant when it is used to target a specific process such as the preparation of anti-cancer drugs. This method helped us to focus on the production steps, which can have a critical influence on product quality, and led us to improve our process.

  10. Importance of good manufacturing practices in microbiological monitoring in processing human tissues for transplant.

    PubMed

    Pianigiani, Elisa; Ierardi, Francesca; Fimiani, Michele

    2013-12-01

    Skin allografts represent an important therapeutic resource in the treatment of severe skin loss. The risk associated with application of processed tissues in humans is very low, however, human material always carries the risk of disease transmission. To minimise the risk of contamination of grafts, processing is carried out in clean rooms where air quality is monitored. Procedures and quality control tests are performed to standardise the production process and to guarantee the final product for human use. Since we only validate and distribute aseptic tissues, we conducted a study to determine what type of quality controls for skin processing are the most suitable for detecting processing errors and intercurrent contamination, and for faithfully mapping the process without unduly increasing production costs. Two different methods for quality control were statistically compared using the Fisher exact test. On the basis of the current study we selected our quality control procedure based on pre- and post-processing tissue controls, operator and environmental controls. Evaluation of the predictability of our control methods showed that tissue control was the most reliable method of revealing microbial contamination of grafts. We obtained 100 % sensitivity by doubling tissue controls, while maintaining high specificity (77 %).

  11. 21 CFR 820.70 - Production and process controls.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... process control procedures that describe any process controls necessary to ensure conformance to specifications. Where process controls are needed they shall include: (1) Documented instructions, standard operating procedures (SOP's), and methods that define and control the manner of production; (2) Monitoring...

  12. 21 CFR 820.70 - Production and process controls.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... process control procedures that describe any process controls necessary to ensure conformance to specifications. Where process controls are needed they shall include: (1) Documented instructions, standard operating procedures (SOP's), and methods that define and control the manner of production; (2) Monitoring...

  13. Plasma process control with optical emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Ward, P. P.

    Plasma processes for cleaning, etching and desmear of electronic components and printed wiring boards (PWB) are difficult to predict and control. Non-uniformity of most plasma processes and sensitivity to environmental changes make it difficult to maintain process stability from day to day. To assure plasma process performance, weight loss coupons or post-plasma destructive testing must be used. The problem with these techniques is that they are not real-time methods and do not allow for immediate diagnosis and process correction. These methods often require scrapping some fraction of a batch to insure the integrity of the rest. Since these methods verify a successful cycle with post-plasma diagnostics, poor test results often determine that a batch is substandard and the resulting parts unusable. Both of these methods are a costly part of the overall fabrication cost. A more efficient method of testing would allow for constant monitoring of plasma conditions and process control. Process failures should be detected before the parts being treated. are damaged. Real time monitoring would allow for instantaneous corrections. Multiple site monitoring would allow for process mapping within one system or simultaneous monitoring of multiple systems. Optical emission spectroscopy conducted external to the plasma apparatus would allow for this sort of multifunctional analysis without perturbing the glow discharge. In this paper, optical emission spectroscopy for non-intrusive, in situ process control will be explored. A discussion of this technique as it applies towards process control, failure analysis and endpoint determination will be conducted. Methods for identifying process failures, progress and end of etch back and desmear processes will be discussed.

  14. Knowledge acquisition for a simple expert controller

    NASA Technical Reports Server (NTRS)

    Bieker, B.

    1987-01-01

    A method is presented for process control which has the properties of being incremental, cyclic and top-down. It is described on the basis of the development of an expert controller for a simple, but nonlinear control route. A quality comparison between expert controller and process operator shows the ability of the method for knowledge acquisition.

  15. A novel process control method for a TT-300 E-Beam/X-Ray system

    NASA Astrophysics Data System (ADS)

    Mittendorfer, Josef; Gallnböck-Wagner, Bernhard

    2018-02-01

    This paper presents some aspects of the process control method for a TT-300 E-Beam/X-Ray system at Mediscan, Austria. The novelty of the approach is the seamless integration of routine monitoring dosimetry with process data. This allows to calculate a parametric dose for each production unit and consequently a fine grain and holistic process performance monitoring. Process performance is documented in process control charts for the analysis of individual runs as well as historic trending of runs of specific process categories over a specified time range.

  16. [Monitoring method of extraction process for Schisandrae Chinensis Fructus based on near infrared spectroscopy and multivariate statistical process control].

    PubMed

    Xu, Min; Zhang, Lei; Yue, Hong-Shui; Pang, Hong-Wei; Ye, Zheng-Liang; Ding, Li

    2017-10-01

    To establish an on-line monitoring method for extraction process of Schisandrae Chinensis Fructus, the formula medicinal material of Yiqi Fumai lyophilized injection by combining near infrared spectroscopy with multi-variable data analysis technology. The multivariate statistical process control (MSPC) model was established based on 5 normal batches in production and 2 test batches were monitored by PC scores, DModX and Hotelling T2 control charts. The results showed that MSPC model had a good monitoring ability for the extraction process. The application of the MSPC model to actual production process could effectively achieve on-line monitoring for extraction process of Schisandrae Chinensis Fructus, and can reflect the change of material properties in the production process in real time. This established process monitoring method could provide reference for the application of process analysis technology in the process quality control of traditional Chinese medicine injections. Copyright© by the Chinese Pharmaceutical Association.

  17. Statistical Process Control Charts for Measuring and Monitoring Temporal Consistency of Ratings

    ERIC Educational Resources Information Center

    Omar, M. Hafidz

    2010-01-01

    Methods of statistical process control were briefly investigated in the field of educational measurement as early as 1999. However, only the use of a cumulative sum chart was explored. In this article other methods of statistical quality control are introduced and explored. In particular, methods in the form of Shewhart mean and standard deviation…

  18. Dynamic Exergy Method for Evaluating the Control and Operation of Oxy-Combustion Boiler Island Systems.

    PubMed

    Jin, Bo; Zhao, Haibo; Zheng, Chuguang; Liang, Zhiwu

    2017-01-03

    Exergy-based methods are widely applied to assess the performance of energy conversion systems; however, these methods mainly focus on a certain steady-state and have limited applications for evaluating the control impacts on system operation. To dynamically obtain the thermodynamic behavior and reveal the influences of control structures, layers and loops, on system energy performance, a dynamic exergy method is developed, improved, and applied to a complex oxy-combustion boiler island system for the first time. The three most common operating scenarios are studied, and the results show that the flow rate change process leads to less energy consumption than oxygen purity and air in-leakage change processes. The variation of oxygen purity produces the largest impact on system operation, and the operating parameter sensitivity is not affected by the presence of process control. The control system saves energy during flow rate and oxygen purity change processes, while it consumes energy during the air in-leakage change process. More attention should be paid to the oxygen purity change because it requires the largest control cost. In the control system, the supervisory control layer requires the greatest energy consumption and the largest control cost to maintain operating targets, while the steam control loops cause the main energy consumption.

  19. A novel double loop control model design for chemical unstable processes.

    PubMed

    Cong, Er-Ding; Hu, Ming-Hui; Tu, Shan-Tung; Xuan, Fu-Zhen; Shao, Hui-He

    2014-03-01

    In this manuscript, based on Smith predictor control scheme for unstable process in industry, an improved double loop control model is proposed for chemical unstable processes. Inner loop is to stabilize integrating the unstable process and transform the original process to first-order plus pure dead-time dynamic stable process. Outer loop is to enhance the performance of set point response. Disturbance controller is designed to enhance the performance of disturbance response. The improved control system is simple with exact physical meaning. The characteristic equation is easy to realize stabilization. Three controllers are separately design in the improved scheme. It is easy to design each controller and good control performance for the respective closed-loop transfer function separately. The robust stability of the proposed control scheme is analyzed. Finally, case studies illustrate that the improved method can give better system performance than existing design methods. © 2013 ISA Published by ISA All rights reserved.

  20. Performance analysis of different tuning rules for an isothermal CSTR using integrated EPC and SPC

    NASA Astrophysics Data System (ADS)

    Roslan, A. H.; Karim, S. F. Abd; Hamzah, N.

    2018-03-01

    This paper demonstrates the integration of Engineering Process Control (EPC) and Statistical Process Control (SPC) for the control of product concentration of an isothermal CSTR. The objectives of this study are to evaluate the performance of Ziegler-Nichols (Z-N), Direct Synthesis, (DS) and Internal Model Control (IMC) tuning methods and determine the most effective method for this process. The simulation model was obtained from past literature and re-constructed using SIMULINK MATLAB to evaluate the process response. Additionally, the process stability, capability and normality were analyzed using Process Capability Sixpack reports in Minitab. Based on the results, DS displays the best response for having the smallest rise time, settling time, overshoot, undershoot, Integral Time Absolute Error (ITAE) and Integral Square Error (ISE). Also, based on statistical analysis, DS yields as the best tuning method as it exhibits the highest process stability and capability.

  1. Intelligent monitoring and control of semiconductor manufacturing equipment

    NASA Technical Reports Server (NTRS)

    Murdock, Janet L.; Hayes-Roth, Barbara

    1991-01-01

    The use of AI methods to monitor and control semiconductor fabrication in a state-of-the-art manufacturing environment called the Rapid Thermal Multiprocessor is described. Semiconductor fabrication involves many complex processing steps with limited opportunities to measure process and product properties. By applying additional process and product knowledge to that limited data, AI methods augment classical control methods by detecting abnormalities and trends, predicting failures, diagnosing, planning corrective action sequences, explaining diagnoses or predictions, and reacting to anomalous conditions that classical control systems typically would not correct. Research methodology and issues are discussed, and two diagnosis scenarios are examined.

  2. SU-D-BRD-07: Evaluation of the Effectiveness of Statistical Process Control Methods to Detect Systematic Errors For Routine Electron Energy Verification

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, S

    2015-06-15

    Purpose: To evaluate the ability of statistical process control methods to detect systematic errors when using a two dimensional (2D) detector array for routine electron beam energy verification. Methods: Electron beam energy constancy was measured using an aluminum wedge and a 2D diode array on four linear accelerators. Process control limits were established. Measurements were recorded in control charts and compared with both calculated process control limits and TG-142 recommended specification limits. The data was tested for normality, process capability and process acceptability. Additional measurements were recorded while systematic errors were intentionally introduced. Systematic errors included shifts in the alignmentmore » of the wedge, incorrect orientation of the wedge, and incorrect array calibration. Results: Control limits calculated for each beam were smaller than the recommended specification limits. Process capability and process acceptability ratios were greater than one in all cases. All data was normally distributed. Shifts in the alignment of the wedge were most apparent for low energies. The smallest shift (0.5 mm) was detectable using process control limits in some cases, while the largest shift (2 mm) was detectable using specification limits in only one case. The wedge orientation tested did not affect the measurements as this did not affect the thickness of aluminum over the detectors of interest. Array calibration dependence varied with energy and selected array calibration. 6 MeV was the least sensitive to array calibration selection while 16 MeV was the most sensitive. Conclusion: Statistical process control methods demonstrated that the data distribution was normally distributed, the process was capable of meeting specifications, and that the process was centered within the specification limits. Though not all systematic errors were distinguishable from random errors, process control limits increased the ability to detect systematic errors using routine measurement of electron beam energy constancy.« less

  3. Feedback control methods for drug dosage optimisation. Concepts, classification and clinical application.

    PubMed

    Vozeh, S; Steimer, J L

    1985-01-01

    The concept of feedback control methods for drug dosage optimisation is described from the viewpoint of control theory. The control system consists of 5 parts: (a) patient (the controlled process); (b) response (the measured feedback); (c) model (the mathematical description of the process); (d) adaptor (to update the parameters); and (e) controller (to determine optimum dosing strategy). In addition to the conventional distinction between open-loop and closed-loop control systems, a classification is proposed for dosage optimisation techniques which distinguishes between tight-loop and loose-loop methods depending on whether physician's interaction is absent or included as part of the control step. Unlike engineering problems where the process can usually be controlled by fully automated devices, therapeutic situations often require that the physician be included in the decision-making process to determine the 'optimal' dosing strategy. Tight-loop and loose-loop methods can be further divided into adaptive and non-adaptive, depending on the presence of the adaptor. The main application areas of tight-loop feedback control methods are general anaesthesia, control of blood pressure, and insulin delivery devices. Loose-loop feedback methods have been used for oral anticoagulation and in therapeutic drug monitoring. The methodology, advantages and limitations of the different approaches are reviewed. A general feature common to all application areas could be observed: to perform well under routine clinical conditions, which are characterised by large interpatient variability and sometimes also intrapatient changes, control systems should be adaptive. Apart from application in routine drug treatment, feedback control methods represent an important research tool. They can be applied for the investigation of pathophysiological and pharmacodynamic processes. A most promising application is the evaluation of the relationship between an intermediate response (e.g. drug level), which is often used as feedback for dosage adjustment, and the final therapeutic goal.

  4. Design of a robust fuzzy controller for the arc stability of CO(2) welding process using the Taguchi method.

    PubMed

    Kim, Dongcheol; Rhee, Sehun

    2002-01-01

    CO(2) welding is a complex process. Weld quality is dependent on arc stability and minimizing the effects of disturbances or changes in the operating condition commonly occurring during the welding process. In order to minimize these effects, a controller can be used. In this study, a fuzzy controller was used in order to stabilize the arc during CO(2) welding. The input variable of the controller was the Mita index. This index estimates quantitatively the arc stability that is influenced by many welding process parameters. Because the welding process is complex, a mathematical model of the Mita index was difficult to derive. Therefore, the parameter settings of the fuzzy controller were determined by performing actual control experiments without using a mathematical model of the controlled process. The solution, the Taguchi method was used to determine the optimal control parameter settings of the fuzzy controller to make the control performance robust and insensitive to the changes in the operating conditions.

  5. Closed-Loop Process Control for Electron Beam Freeform Fabrication and Deposition Processes

    NASA Technical Reports Server (NTRS)

    Taminger, Karen M. (Inventor); Hofmeister, William H. (Inventor); Martin, Richard E. (Inventor); Hafley, Robert A. (Inventor)

    2013-01-01

    A closed-loop control method for an electron beam freeform fabrication (EBF(sup 3)) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF(sup 3) process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF(sup 3) apparatus to control the EBF(sup 3) process in a closed-loop manner.

  6. Statistical Process Control: Going to the Limit for Quality.

    ERIC Educational Resources Information Center

    Training, 1987

    1987-01-01

    Defines the concept of statistical process control, a quality control method used especially in manufacturing. Generally, concept users set specific standard levels that must be met. Makes the point that although employees work directly with the method, management is responsible for its success within the plant. (CH)

  7. Numerical simulation of the control of the three-dimensional transition process in boundary layers

    NASA Technical Reports Server (NTRS)

    Kral, L. D.; Fasel, H. F.

    1990-01-01

    Surface heating techniques to control the three-dimensional laminar-turbulent transition process are numerically investigated for a water boundary layer. The Navier-Stokes and energy equations are solved using a fully implicit finite difference/spectral method. The spatially evolving boundary layer is simulated. Results of both passive and active methods of control are shown for small amplitude two-dimensional and three-dimensional disturbance waves. Control is also applied to the early stages of the secondary instability process using passive or active control techniques.

  8. Development of Process Analytical Technology (PAT) methods for controlled release pellet coating.

    PubMed

    Avalle, P; Pollitt, M J; Bradley, K; Cooper, B; Pearce, G; Djemai, A; Fitzpatrick, S

    2014-07-01

    This work focused on the control of the manufacturing process for a controlled release (CR) pellet product, within a Quality by Design (QbD) framework. The manufacturing process was Wurster coating: firstly layering active pharmaceutical ingredient (API) onto sugar pellet cores and secondly a controlled release (CR) coating. For each of these two steps, development of a Process Analytical Technology (PAT) method is discussed and also a novel application of automated microscopy as the reference method. Ultimately, PAT methods should link to product performance and the two key Critical Quality Attributes (CQAs) for this CR product are assay and release rate, linked to the API and CR coating steps respectively. In this work, the link between near infra-red (NIR) spectra and those attributes was explored by chemometrics over the course of the coating process in a pilot scale industrial environment. Correlations were built between the NIR spectra and coating weight (for API amount), CR coating thickness and dissolution performance. These correlations allow the coating process to be monitored at-line and so better control of the product performance in line with QbD requirements. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Single bus star connected reluctance drive and method

    DOEpatents

    Fahimi, Babak; Shamsi, Pourya

    2016-05-10

    A system and methods for operating a switched reluctance machine includes a controller, an inverter connected to the controller and to the switched reluctance machine, a hysteresis control connected to the controller and to the inverter, a set of sensors connected to the switched reluctance machine and to the controller, the switched reluctance machine further including a set of phases the controller further comprising a processor and a memory connected to the processor, wherein the processor programmed to execute a control process and a generation process.

  10. A Model-based B2B (Batch to Batch) Control for An Industrial Batch Polymerization Process

    NASA Astrophysics Data System (ADS)

    Ogawa, Morimasa

    This paper describes overview of a model-based B2B (batch to batch) control for an industrial batch polymerization process. In order to control the reaction temperature precisely, several methods based on the rigorous process dynamics model are employed at all design stage of the B2B control, such as modeling and parameter estimation of the reaction kinetics which is one of the important part of the process dynamics model. The designed B2B control consists of the gain scheduled I-PD/II2-PD control (I-PD with double integral control), the feed-forward compensation at the batch start time, and the model adaptation utilizing the results of the last batch operation. Throughout the actual batch operations, the B2B control provides superior control performance compared with that of conventional control methods.

  11. Statistical process control methods allow the analysis and improvement of anesthesia care.

    PubMed

    Fasting, Sigurd; Gisvold, Sven E

    2003-10-01

    Quality aspects of the anesthetic process are reflected in the rate of intraoperative adverse events. The purpose of this report is to illustrate how the quality of the anesthesia process can be analyzed using statistical process control methods, and exemplify how this analysis can be used for quality improvement. We prospectively recorded anesthesia-related data from all anesthetics for five years. The data included intraoperative adverse events, which were graded into four levels, according to severity. We selected four adverse events, representing important quality and safety aspects, for statistical process control analysis. These were: inadequate regional anesthesia, difficult emergence from general anesthesia, intubation difficulties and drug errors. We analyzed the underlying process using 'p-charts' for statistical process control. In 65,170 anesthetics we recorded adverse events in 18.3%; mostly of lesser severity. Control charts were used to define statistically the predictable normal variation in problem rate, and then used as a basis for analysis of the selected problems with the following results: Inadequate plexus anesthesia: stable process, but unacceptably high failure rate; Difficult emergence: unstable process, because of quality improvement efforts; Intubation difficulties: stable process, rate acceptable; Medication errors: methodology not suited because of low rate of errors. By applying statistical process control methods to the analysis of adverse events, we have exemplified how this allows us to determine if a process is stable, whether an intervention is required, and if quality improvement efforts have the desired effect.

  12. 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.

  13. Adaptive GSA-based optimal tuning of PI controlled servo systems with reduced process parametric sensitivity, robust stability and controller robustness.

    PubMed

    Precup, Radu-Emil; David, Radu-Codrut; Petriu, Emil M; Radac, Mircea-Bogdan; Preitl, Stefan

    2014-11-01

    This paper suggests a new generation of optimal PI controllers for a class of servo systems characterized by saturation and dead zone static nonlinearities and second-order models with an integral component. The objective functions are expressed as the integral of time multiplied by absolute error plus the weighted sum of the integrals of output sensitivity functions of the state sensitivity models with respect to two process parametric variations. The PI controller tuning conditions applied to a simplified linear process model involve a single design parameter specific to the extended symmetrical optimum (ESO) method which offers the desired tradeoff to several control system performance indices. An original back-calculation and tracking anti-windup scheme is proposed in order to prevent the integrator wind-up and to compensate for the dead zone nonlinearity of the process. The minimization of the objective functions is carried out in the framework of optimization problems with inequality constraints which guarantee the robust stability with respect to the process parametric variations and the controller robustness. An adaptive gravitational search algorithm (GSA) solves the optimization problems focused on the optimal tuning of the design parameter specific to the ESO method and of the anti-windup tracking gain. A tuning method for PI controllers is proposed as an efficient approach to the design of resilient control systems. The tuning method and the PI controllers are experimentally validated by the adaptive GSA-based tuning of PI controllers for the angular position control of a laboratory servo system.

  14. Availability Control for Means of Transport in Decisive Semi-Markov Models of Exploitation Process

    NASA Astrophysics Data System (ADS)

    Migawa, Klaudiusz

    2012-12-01

    The issues presented in this research paper refer to problems connected with the control process for exploitation implemented in the complex systems of exploitation for technical objects. The article presents the description of the method concerning the control availability for technical objects (means of transport) on the basis of the mathematical model of the exploitation process with the implementation of the decisive processes by semi-Markov. The presented method means focused on the preparing the decisive for the exploitation process for technical objects (semi-Markov model) and after that specifying the best control strategy (optimal strategy) from among possible decisive variants in accordance with the approved criterion (criteria) of the activity evaluation of the system of exploitation for technical objects. In the presented method specifying the optimal strategy for control availability in the technical objects means a choice of a sequence of control decisions made in individual states of modelled exploitation process for which the function being a criterion of evaluation reaches the extreme value. In order to choose the optimal control strategy the implementation of the genetic algorithm was chosen. The opinions were presented on the example of the exploitation process of the means of transport implemented in the real system of the bus municipal transport. The model of the exploitation process for the means of transports was prepared on the basis of the results implemented in the real transport system. The mathematical model of the exploitation process was built taking into consideration the fact that the model of the process constitutes the homogenous semi-Markov process.

  15. Statistical process control: A feasibility study of the application of time-series measurement in early neurorehabilitation after acquired brain injury.

    PubMed

    Markovic, Gabriela; Schult, Marie-Louise; Bartfai, Aniko; Elg, Mattias

    2017-01-31

    Progress in early cognitive recovery after acquired brain injury is uneven and unpredictable, and thus the evaluation of rehabilitation is complex. The use of time-series measurements is susceptible to statistical change due to process variation. To evaluate the feasibility of using a time-series method, statistical process control, in early cognitive rehabilitation. Participants were 27 patients with acquired brain injury undergoing interdisciplinary rehabilitation of attention within 4 months post-injury. The outcome measure, the Paced Auditory Serial Addition Test, was analysed using statistical process control. Statistical process control identifies if and when change occurs in the process according to 3 patterns: rapid, steady or stationary performers. The statistical process control method was adjusted, in terms of constructing the baseline and the total number of measurement points, in order to measure a process in change. Statistical process control methodology is feasible for use in early cognitive rehabilitation, since it provides information about change in a process, thus enabling adjustment of the individual treatment response. Together with the results indicating discernible subgroups that respond differently to rehabilitation, statistical process control could be a valid tool in clinical decision-making. This study is a starting-point in understanding the rehabilitation process using a real-time-measurements approach.

  16. Control of chemical dynamics by lasers: theoretical considerations.

    PubMed

    Kondorskiy, Alexey; Nanbu, Shinkoh; Teranishi, Yoshiaki; Nakamura, Hiroki

    2010-06-03

    Theoretical ideas are proposed for laser control of chemical dynamics. There are the following three elementary processes in chemical dynamics: (i) motion of the wave packet on a single adiabatic potential energy surface, (ii) excitation/de-excitation or pump/dump of wave packet, and (iii) nonadiabatic transitions at conical intersections of potential energy surfaces. A variety of chemical dynamics can be controlled, if we can control these three elementary processes as we desire. For (i) we have formulated the semiclassical guided optimal control theory, which can be applied to multidimensional real systems. The quadratic or periodic frequency chirping method can achieve process (ii) with high efficiency close to 100%. Concerning process (iii) mentioned above, the directed momentum method, in which a predetermined momentum vector is given to the initial wave packet, makes it possible to enhance the desired transitions at conical intersections. In addition to these three processes, the intriguing phenomenon of complete reflection in the nonadiabatic-tunneling-type of potential curve crossing can also be used to control a certain class of chemical dynamics. The basic ideas and theoretical formulations are provided for the above-mentioned processes. To demonstrate the effectiveness of these controlling methods, numerical examples are shown by taking the following processes: (a) vibrational photoisomerization of HCN, (b) selective and complete excitation of the fine structure levels of K and Cs atoms, (c) photoconversion of cyclohexadiene to hexatriene, and (d) photodissociation of OHCl to O + HCl.

  17. Interrupted Time Series Versus Statistical Process Control in Quality Improvement Projects.

    PubMed

    Andersson Hagiwara, Magnus; Andersson Gäre, Boel; Elg, Mattias

    2016-01-01

    To measure the effect of quality improvement interventions, it is appropriate to use analysis methods that measure data over time. Examples of such methods include statistical process control analysis and interrupted time series with segmented regression analysis. This article compares the use of statistical process control analysis and interrupted time series with segmented regression analysis for evaluating the longitudinal effects of quality improvement interventions, using an example study on an evaluation of a computerized decision support system.

  18. System and method for networking electrochemical devices

    DOEpatents

    Williams, Mark C.; Wimer, John G.; Archer, David H.

    1995-01-01

    An improved electrochemically active system and method including a plurality of electrochemical devices, such as fuel cells and fluid separation devices, in which the anode and cathode process-fluid flow chambers are connected in fluid-flow arrangements so that the operating parameters of each of said plurality of electrochemical devices which are dependent upon process-fluid parameters may be individually controlled to provide improved operating efficiency. The improvements in operation include improved power efficiency and improved fuel utilization in fuel cell power generating systems and reduced power consumption in fluid separation devices and the like through interstage process fluid parameter control for series networked electrochemical devices. The improved networking method includes recycling of various process flows to enhance the overall control scheme.

  19. Off-Line Quality Control In Integrated Circuit Fabrication Using Experimental Design

    NASA Astrophysics Data System (ADS)

    Phadke, M. S.; Kackar, R. N.; Speeney, D. V.; Grieco, M. J.

    1987-04-01

    Off-line quality control is a systematic method of optimizing production processes and product designs. It is widely used in Japan to produce high quality products at low cost. The method was introduced to us by Professor Genichi Taguchi who is a Deming-award winner and a former Director of the Japanese Academy of Quality. In this paper we will i) describe the off-line quality control method, and ii) document our efforts to optimize the process for forming contact windows in 3.5 Aim CMOS circuits fabricated in the Murray Hill Integrated Circuit Design Capability Laboratory. In the fabrication of integrated circuits it is critically important to produce contact windows of size very near the target dimension. Windows which are too small or too large lead to loss of yield. The off-line quality control method has improved both the process quality and productivity. The variance of the window size has been reduced by a factor of four. Also, processing time for window photolithography has been substantially reduced. The key steps of off-line quality control are: i) Identify important manipulatable process factors and their potential working levels. ii) Perform fractional factorial experiments on the process using orthogonal array designs. iii) Analyze the resulting data to determine the optimum operating levels of the factors. Both the process mean and the process variance are considered in this analysis. iv) Conduct an additional experiment to verify that the new factor levels indeed give an improvement.

  20. Assessing the influence of component processing and donor characteristics on quality of red cell concentrates using quality control data.

    PubMed

    Jordan, A; Chen, D; Yi, Q-L; Kanias, T; Gladwin, M T; Acker, J P

    2016-07-01

    Quality control (QC) data collected by blood services are used to monitor production and to ensure compliance with regulatory standards. We demonstrate how analysis of quality control data can be used to highlight the sources of variability within red cell concentrates (RCCs). We merged Canadian Blood Services QC data with manufacturing and donor records for 28 227 RCC between June 2011 and October 2014. Units were categorized based on processing method, bag manufacturer, donor age and donor sex, then assessed based on product characteristics: haemolysis and haemoglobin levels, unit volume, leucocyte count and haematocrit. Buffy-coat method (top/bottom)-processed units exhibited lower haemolysis than units processed using the whole-blood filtration method (top/top). Units from female donors exhibited lower haemolysis than male donations. Processing method influenced unit volume and the ratio of additive solution to residual plasma. Stored red blood cell characteristics are influenced by prestorage processing and donor factors. Understanding the relationship between processing, donors and RCC quality will help blood services to ensure the safety of transfused products. © 2016 International Society of Blood Transfusion.

  1. Process control monitoring systems, industrial plants, and process control monitoring methods

    DOEpatents

    Skorpik, James R [Kennewick, WA; Gosselin, Stephen R [Richland, WA; Harris, Joe C [Kennewick, WA

    2010-09-07

    A system comprises a valve; a plurality of RFID sensor assemblies coupled to the valve to monitor a plurality of parameters associated with the valve; a control tag configured to wirelessly communicate with the respective tags that are coupled to the valve, the control tag being further configured to communicate with an RF reader; and an RF reader configured to selectively communicate with the control tag, the reader including an RF receiver. Other systems and methods are also provided.

  2. An architecture for designing fuzzy logic controllers using neural networks

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1991-01-01

    Described here is an architecture for designing fuzzy controllers through a hierarchical process of control rule acquisition and by using special classes of neural network learning techniques. A new method for learning to refine a fuzzy logic controller is introduced. A reinforcement learning technique is used in conjunction with a multi-layer neural network model of a fuzzy controller. The model learns by updating its prediction of the plant's behavior and is related to the Sutton's Temporal Difference (TD) method. The method proposed here has the advantage of using the control knowledge of an experienced operator and fine-tuning it through the process of learning. The approach is applied to a cart-pole balancing system.

  3. Self-tuning regulator for an interacting CSTR process

    NASA Astrophysics Data System (ADS)

    Rajendra Mungale, Niraj; Upadhyay, Akshay; Jaganatha Pandian, B.

    2017-11-01

    In the paper we have laid emphasis on STR that is Self Tuning Regulator and its application for an interacting process. CSTR has a great importance in Chemical Process when we deal with controlling different parameters of a process using CSTR. Basically CSTR is used to maintain a constant liquid temperature in the process. The proposed method called self-tuning regulator, is a different scheme where process parameters are updated and the controller parameters are obtained from the solution of a design problem. The paper deals with STR and methods associated with it.

  4. Nonlinear Performance Seeking Control using Fuzzy Model Reference Learning Control and the Method of Steepest Descent

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    1997-01-01

    Performance Seeking Control (PSC) attempts to find and control the process at the operating condition that will generate maximum performance. In this paper a nonlinear multivariable PSC methodology will be developed, utilizing the Fuzzy Model Reference Learning Control (FMRLC) and the method of Steepest Descent or Gradient (SDG). This PSC control methodology employs the SDG method to find the operating condition that will generate maximum performance. This operating condition is in turn passed to the FMRLC controller as a set point for the control of the process. The conventional SDG algorithm is modified in this paper in order for convergence to occur monotonically. For the FMRLC control, the conventional fuzzy model reference learning control methodology is utilized, with guidelines generated here for effective tuning of the FMRLC controller.

  5. Does daily nurse staffing match ward workload variability? Three hospitals' experiences.

    PubMed

    Gabbay, Uri; Bukchin, Michael

    2009-01-01

    Nurse shortage and rising healthcare resource burdens mean that appropriate workforce use is imperative. This paper aims to evaluate whether daily nursing staffing meets ward workload needs. Nurse attendance and daily nurses' workload capacity in three hospitals were evaluated. Statistical process control was used to evaluate intra-ward nurse workload capacity and day-to-day variations. Statistical process control is a statistics-based method for process monitoring that uses charts with predefined target measure and control limits. Standardization was performed for inter-ward analysis by converting ward-specific crude measures to ward-specific relative measures by dividing observed/expected. Two charts: acceptable and tolerable daily nurse workload intensity, were defined. Appropriate staffing indicators were defined as those exceeding predefined rates within acceptable and tolerable limits (50 percent and 80 percent respectively). A total of 42 percent of the overall days fell within acceptable control limits and 71 percent within tolerable control limits. Appropriate staffing indicators were met in only 33 percent of wards regarding acceptable nurse workload intensity and in only 45 percent of wards regarding tolerable workloads. The study work did not differentiate crude nurse attendance and it did not take into account patient severity since crude bed occupancy was used. Double statistical process control charts and certain staffing indicators were used, which is open to debate. Wards that met appropriate staffing indicators prove the method's feasibility. Wards that did not meet appropriate staffing indicators prove the importance and the need for process evaluations and monitoring. Methods presented for monitoring daily staffing appropriateness are simple to implement either for intra-ward day-to-day variation by using nurse workload capacity statistical process control charts or for inter-ward evaluation using standardized measure of nurse workload intensity. The real challenge will be to develop planning systems and implement corrective interventions such as dynamic and flexible daily staffing, which will face difficulties and barriers. The paper fulfils the need for workforce utilization evaluation. A simple method using available data for daily staffing appropriateness evaluation, which is easy to implement and operate, is presented. The statistical process control method enables intra-ward evaluation, while standardization by converting crude into relative measures enables inter-ward analysis. The staffing indicator definitions enable performance evaluation. This original study uses statistical process control to develop simple standardization methods and applies straightforward statistical tools. This method is not limited to crude measures, rather it uses weighted workload measures such as nursing acuity or weighted nurse level (i.e. grade/band).

  6. Dynamic control of remelting processes

    DOEpatents

    Bertram, Lee A.; Williamson, Rodney L.; Melgaard, David K.; Beaman, Joseph J.; Evans, David G.

    2000-01-01

    An apparatus and method of controlling a remelting process by providing measured process variable values to a process controller; estimating process variable values using a process model of a remelting process; and outputting estimated process variable values from the process controller. Feedback and feedforward control devices receive the estimated process variable values and adjust inputs to the remelting process. Electrode weight, electrode mass, electrode gap, process current, process voltage, electrode position, electrode temperature, electrode thermal boundary layer thickness, electrode velocity, electrode acceleration, slag temperature, melting efficiency, cooling water temperature, cooling water flow rate, crucible temperature profile, slag skin temperature, and/or drip short events are employed, as are parameters representing physical constraints of electroslag remelting or vacuum arc remelting, as applicable.

  7. A new integrated evaluation method of heavy metals pollution control during melting and sintering of MSWI fly ash.

    PubMed

    Li, Rundong; Li, Yanlong; Yang, Tianhua; Wang, Lei; Wang, Weiyun

    2015-05-30

    Evaluations of technologies for heavy metal control mainly examine the residual and leaching rates of a single heavy metal, such that developed evaluation method have no coordination or uniqueness and are therefore unsuitable for hazard control effect evaluation. An overall pollution toxicity index (OPTI) was established in this paper, based on the developed index, an integrated evaluation method of heavy metal pollution control was established. Application of this method in the melting and sintering of fly ash revealed the following results: The integrated control efficiency of the melting process was higher in all instances than that of the sintering process. The lowest integrated control efficiency of melting was 56.2%, and the highest integrated control efficiency of sintering was 46.6%. Using the same technology, higher integrated control efficiency conditions were all achieved with lower temperatures and shorter times. This study demonstrated the unification and consistency of this method. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Quality status display for a vibration welding process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spicer, John Patrick; Abell, Jeffrey A.; Wincek, Michael Anthony

    A method includes receiving, during a vibration welding process, a set of sensory signals from a collection of sensors positioned with respect to a work piece during formation of a weld on or within the work piece. The method also includes receiving control signals from a welding controller during the process, with the control signals causing the welding horn to vibrate at a calibrated frequency, and processing the received sensory and control signals using a host machine. Additionally, the method includes displaying a predicted weld quality status on a surface of the work piece using a status projector. The methodmore » may include identifying and display a quality status of a suspect weld. The laser projector may project a laser beam directly onto or immediately adjacent to the suspect welds, e.g., as a red, green, blue laser or a gas laser having a switched color filter.« less

  9. Contamination Control in Hybrid Microelectronic Modules. Part 1: Identification of Critical Process and Contaminants

    NASA Technical Reports Server (NTRS)

    Himmel, R. P.

    1975-01-01

    Various hybrid processing steps, handling procedures, and materials are examined in an attempt to identify sources of contamination and to propose methods for the control of these contaminants. It is found that package sealing, assembly, and rework are especially susceptible to contamination. Moisture and loose particles are identified as the worst contaminants. The points at which contaminants are most likely to enter the hybrid package are also identified, and both general and specific methods for their detection and control are developed. In general, the most effective controls for contaminants are: clean working areas, visual inspection at each step of the process, and effective cleaning at critical process steps. Specific methods suggested include the detection of loose particles by a precap visual inspection, by preseal and post-seal electrical testing, and by a particle impact noise test. Moisture is best controlled by sealing all packages in a clean, dry, inert atmosphere after a thorough bake-out of all parts.

  10. Two-degree-of-freedom fractional order-PID controllers design for fractional order processes with dead-time.

    PubMed

    Li, Mingjie; Zhou, Ping; Zhao, Zhicheng; Zhang, Jinggang

    2016-03-01

    Recently, fractional order (FO) processes with dead-time have attracted more and more attention of many researchers in control field, but FO-PID controllers design techniques available for the FO processes with dead-time suffer from lack of direct systematic approaches. In this paper, a simple design and parameters tuning approach of two-degree-of-freedom (2-DOF) FO-PID controller based on internal model control (IMC) is proposed for FO processes with dead-time, conventional one-degree-of-freedom control exhibited the shortcoming of coupling of robustness and dynamic response performance. 2-DOF control can overcome the above weakness which means it realizes decoupling of robustness and dynamic performance from each other. The adjustable parameter η2 of FO-PID controller is directly related to the robustness of closed-loop system, and the analytical expression is given between the maximum sensitivity specification Ms and parameters η2. In addition, according to the dynamic performance requirement of the practical system, the parameters η1 can also be selected easily. By approximating the dead-time term of the process model with the first-order Padé or Taylor series, the expressions for 2-DOF FO-PID controller parameters are derived for three classes of FO processes with dead-time. Moreover, compared with other methods, the proposed method is simple and easy to implement. Finally, the simulation results are given to illustrate the effectiveness of this method. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Modeling of feed-forward control using the partial least squares regression method in the tablet compression process.

    PubMed

    Hattori, Yusuke; Otsuka, Makoto

    2017-05-30

    In the pharmaceutical industry, the implementation of continuous manufacturing has been widely promoted in lieu of the traditional batch manufacturing approach. More specially, in recent years, the innovative concept of feed-forward control has been introduced in relation to process analytical technology. In the present study, we successfully developed a feed-forward control model for the tablet compression process by integrating data obtained from near-infrared (NIR) spectra and the physical properties of granules. In the pharmaceutical industry, batch manufacturing routinely allows for the preparation of granules with the desired properties through the manual control of process parameters. On the other hand, continuous manufacturing demands the automatic determination of these process parameters. Here, we proposed the development of a control model using the partial least squares regression (PLSR) method. The most significant feature of this method is the use of dataset integrating both the NIR spectra and the physical properties of the granules. Using our model, we determined that the properties of products, such as tablet weight and thickness, need to be included as independent variables in the PLSR analysis in order to predict unknown process parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. [Investigation on production process quality control of traditional Chinese medicine--Banlangen granule as an example].

    PubMed

    Tan, Manrong; Yan, Dan; Qiu, Lingling; Chen, Longhu; Yan, Yan; Jin, Cheng; Li, Hanbing; Xiao, Xiaohe

    2012-04-01

    For the quality management system of herbal medicines, intermediate and finished products it exists the " short board" effect of methodologies. Based on the concept of process control, new strategies and new methods of the production process quality control had been established with the consideration of the actual production of traditional Chinese medicine an the characteristics of Chinese medicine. Taking Banlangen granule as a practice example, which was effective and widespread application, character identification, determination of index components, chemical fingerprint and biometrics technology were sequentially used respectively to assess the quality of Banlangen herbal medicines, intermediate (water extraction and alcohol precipitation) and finished product. With the transfer rate of chemical information and biological potency as indicators, the effectiveness and transmission of the above different assessments and control methods had been researched. And ultimately, the process quality control methods of Banlangen granule, which were based on chemical composition analysis-biometric analysis, had been set up. It can not only validly solute the current status that there were many manufacturers varying quality of Banlangen granule, but also ensure and enhance its clinical efficacy. Furthermore it provided a foundation for the construction of the quality control of traditional Chinese medicine production process.

  13. Errors in patient specimen collection: application of statistical process control.

    PubMed

    Dzik, Walter Sunny; Beckman, Neil; Selleng, Kathleen; Heddle, Nancy; Szczepiorkowski, Zbigniew; Wendel, Silvano; Murphy, Michael

    2008-10-01

    Errors in the collection and labeling of blood samples for pretransfusion testing increase the risk of transfusion-associated patient morbidity and mortality. Statistical process control (SPC) is a recognized method to monitor the performance of a critical process. An easy-to-use SPC method was tested to determine its feasibility as a tool for monitoring quality in transfusion medicine. SPC control charts were adapted to a spreadsheet presentation. Data tabulating the frequency of mislabeled and miscollected blood samples from 10 hospitals in five countries from 2004 to 2006 were used to demonstrate the method. Control charts were produced to monitor process stability. The participating hospitals found the SPC spreadsheet very suitable to monitor the performance of the sample labeling and collection and applied SPC charts to suit their specific needs. One hospital monitored subcategories of sample error in detail. A large hospital monitored the number of wrong-blood-in-tube (WBIT) events. Four smaller-sized facilities, each following the same policy for sample collection, combined their data on WBIT samples into a single control chart. One hospital used the control chart to monitor the effect of an educational intervention. A simple SPC method is described that can monitor the process of sample collection and labeling in any hospital. SPC could be applied to other critical steps in the transfusion processes as a tool for biovigilance and could be used to develop regional or national performance standards for pretransfusion sample collection. A link is provided to download the spreadsheet for free.

  14. A new method for defining and managing process alarms and for correcting process operation when an alarm occurs.

    PubMed

    Brooks, Robin; Thorpe, Richard; Wilson, John

    2004-11-11

    A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.

  15. Applied Behavior Analysis and Statistical Process Control?

    ERIC Educational Resources Information Center

    Hopkins, B. L.

    1995-01-01

    Incorporating statistical process control (SPC) methods into applied behavior analysis is discussed. It is claimed that SPC methods would likely reduce applied behavior analysts' intimate contacts with problems and would likely yield poor treatment and research decisions. Cases and data presented by Pfadt and Wheeler (1995) are cited as examples.…

  16. Taguchi Method Applied in Optimization of Shipley SJR 5740 Positive Resist Deposition

    NASA Technical Reports Server (NTRS)

    Hui, A.; Blosiu, J. O.; Wiberg, D. V.

    1998-01-01

    Taguchi Methods of Robust Design presents a way to optimize output process performance through an organized set of experiments by using orthogonal arrays. Analysis of variance and signal-to-noise ratio is used to evaluate the contribution of each of the process controllable parameters in the realization of the process optimization. In the photoresist deposition process, there are numerous controllable parameters that can affect the surface quality and thickness of the final photoresist layer.

  17. The Myriad Strategies for Seeking Control in the Dying Process

    ERIC Educational Resources Information Center

    Schroepfer, Tracy A.; Noh, Hyunjin; Kavanaugh, Melinda

    2009-01-01

    Purpose: This study explored the role control plays in the dying process of terminally ill elders by investigating the aspects of the dying process over which they seek to exercise control, the strategies they use, and whether they desire to exercise more control. Design and Methods: In-depth face-to-face interviews were conducted with 84…

  18. Fault tolerant control of multivariable processes using auto-tuning PID controller.

    PubMed

    Yu, Ding-Li; Chang, T K; Yu, Ding-Wen

    2005-02-01

    Fault tolerant control of dynamic processes is investigated in this paper using an auto-tuning PID controller. A fault tolerant control scheme is proposed composing an auto-tuning PID controller based on an adaptive neural network model. The model is trained online using the extended Kalman filter (EKF) algorithm to learn system post-fault dynamics. Based on this model, the PID controller adjusts its parameters to compensate the effects of the faults, so that the control performance is recovered from degradation. The auto-tuning algorithm for the PID controller is derived with the Lyapunov method and therefore, the model predicted tracking error is guaranteed to converge asymptotically. The method is applied to a simulated two-input two-output continuous stirred tank reactor (CSTR) with various faults, which demonstrate the applicability of the developed scheme to industrial processes.

  19. Multi-mode ultrasonic welding control and optimization

    DOEpatents

    Tang, Jason C.H.; Cai, Wayne W

    2013-05-28

    A system and method for providing multi-mode control of an ultrasonic welding system. In one embodiment, the control modes include the energy of the weld, the time of the welding process and the compression displacement of the parts being welded during the welding process. The method includes providing thresholds for each of the modes, and terminating the welding process after the threshold for each mode has been reached, the threshold for more than one mode has been reached or the threshold for one of the modes has been reached. The welding control can be either open-loop or closed-loop, where the open-loop process provides the mode thresholds and once one or more of those thresholds is reached the welding process is terminated. The closed-loop control provides feedback of the weld energy and/or the compression displacement so that the weld power and/or weld pressure can be increased or decreased accordingly.

  20. An efficient, maintenance free and approved method for spectroscopic control and monitoring of blend uniformity: The moving F-test.

    PubMed

    Besseling, Rut; Damen, Michiel; Tran, Thanh; Nguyen, Thanh; van den Dries, Kaspar; Oostra, Wim; Gerich, Ad

    2015-10-10

    Dry powder mixing is a wide spread Unit Operation in the Pharmaceutical industry. With the advent of in-line Near Infrared (NIR) Spectroscopy and Quality by Design principles, application of Process Analytical Technology to monitor Blend Uniformity (BU) is taking a more prominent role. Yet routine use of NIR for monitoring, let alone control of blending processes is not common in the industry, despite the improved process understanding and (cost) efficiency that it may offer. Method maintenance, robustness and translation to regulatory requirements have been important barriers to implement the method. This paper presents a qualitative NIR-BU method offering a convenient and compliant approach to apply BU control for routine operation and process understanding, without extensive calibration and method maintenance requirements. The method employs a moving F-test to detect the steady state of measured spectral variances and the endpoint of mixing. The fundamentals and performance characteristics of the method are first presented, followed by a description of the link to regulatory BU criteria, the method sensitivity and practical considerations. Applications in upscaling, tech transfer and commercial production are described, along with evaluation of the method performance by comparison with results from quantitative calibration models. A full application, in which end-point detection via the F-test controls the blending process of a low dose product, was successfully filed in Europe and Australia, implemented in commercial production and routinely used for about five years and more than 100 batches. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Method and Apparatus for Improved Spatial Light Modulation

    NASA Technical Reports Server (NTRS)

    Soutar, Colin (Inventor); Juday, Richard D. (Inventor)

    2000-01-01

    A method and apparatus for modulating a light beam in an optical processing system is described. Preferably, an electrically-controlled polarizer unit and/or an analyzer unit are utilized in combination with a spatial light modulator and a controller. Preferably, the spatial light modulator comprises a pixelated birefringent medium such as a liquid crystal video display. The combination of the electrically controlled polarizer unit and analyzer unit make it simple and fast to reconfigure the modulation described by the Jones matrix of the spatial light modulator. A particular optical processing objective is provided to the controller. The controller performs calculations and supplies control signals to the polarizer unit, the analyzer unit, and the spatial light modulator in order to obtain the optical processing objective.

  2. Method and Apparatus for Improved Spatial Light Modulation

    NASA Technical Reports Server (NTRS)

    Colin, Soutar (Inventor); Juday, Richard D. (Inventor)

    1999-01-01

    A method and apparatus for modulating a light beam in an optical processing system is described. Preferably, an electrically-controlled polarizer unit and/or an analyzer unit are utilized in combination with a spatial light modulator and a controller. Preferably, the spatial light modulator comprises a pixelated birefringent medium such as a liquid crystal video display. The combination of the electrically controlled polarizer unit and analyzer unit make it simple and fast to reconfigure the modulation described by the Jones matrix of the spatial light modulator. A particular optical processing objective is provided to the controller. The controller performs calculations and supplies control signals to the polarizer unit, the analyzer unit, and the spatial light modulator in order to obtain die optical processing objective.

  3. [Analysis and countermeasure for quality risk in process of traditional Chinese medicine preparations].

    PubMed

    Yang, Ming; Yang, Yuan-Zhen; Wang, Ya-Qi; Wu, Zhen-Feng; Wang, Xue-Cheng; Luo, Jing

    2017-03-01

    Product quality relies on not only testing methods,but also the design and development, production control and product manufacturing all aspects of logistics management. Quality comes from the process control level.Therefore, it is very important to accurately identify the factors that may induce quality risk in the production process and quality control measures correspondingly.This article systematically analyzes the source of the quality risk of all aspects of the production process in traditional Chinese medicine preparation. Discussing ways and methods of quality risk identification of traditional Chinese medicine preparation and providing references for perfecting the whole process quality management of traditional Chinese medicine preparation. Copyright© by the Chinese Pharmaceutical Association.

  4. Gas turbine engine control system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Idelchik, M.S.

    1991-02-19

    This paper describes a method for controlling a gas turbine engine. It includes receiving an error signal and processing the error signal to form a primary control signal; receiving at least one anticipatory demand signal and processing the signal to form an anticipatory fuel control signal.

  5. Control chart pattern recognition using RBF neural network with new training algorithm and practical features.

    PubMed

    Addeh, Abdoljalil; Khormali, Aminollah; Golilarz, Noorbakhsh Amiri

    2018-05-04

    The control chart patterns are the most commonly used statistical process control (SPC) tools to monitor process changes. When a control chart produces an out-of-control signal, this means that the process has been changed. In this study, a new method based on optimized radial basis function neural network (RBFNN) is proposed for control chart patterns (CCPs) recognition. The proposed method consists of four main modules: feature extraction, feature selection, classification and learning algorithm. In the feature extraction module, shape and statistical features are used. Recently, various shape and statistical features have been presented for the CCPs recognition. In the feature selection module, the association rules (AR) method has been employed to select the best set of the shape and statistical features. In the classifier section, RBFNN is used and finally, in RBFNN, learning algorithm has a high impact on the network performance. Therefore, a new learning algorithm based on the bees algorithm has been used in the learning module. Most studies have considered only six patterns: Normal, Cyclic, Increasing Trend, Decreasing Trend, Upward Shift and Downward Shift. Since three patterns namely Normal, Stratification, and Systematic are very similar to each other and distinguishing them is very difficult, in most studies Stratification and Systematic have not been considered. Regarding to the continuous monitoring and control over the production process and the exact type detection of the problem encountered during the production process, eight patterns have been investigated in this study. The proposed method is tested on a dataset containing 1600 samples (200 samples from each pattern) and the results showed that the proposed method has a very good performance. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Quality Control of the Print with the Application of Statistical Methods

    NASA Astrophysics Data System (ADS)

    Simonenko, K. V.; Bulatova, G. S.; Antropova, L. B.; Varepo, L. G.

    2018-04-01

    The basis for standardizing the process of offset printing is the control of print quality indicators. The solution of this problem has various approaches, among which the most important are statistical methods. Practical implementation of them for managing the quality of the printing process is very relevant and is reflected in this paper. The possibility of using the method of constructing a Control Card to identify the reasons for the deviation of the optical density for a triad of inks in offset printing is shown.

  7. Improved process robustness by using closed loop control in deep drawing applications

    NASA Astrophysics Data System (ADS)

    Barthau, M.; Liewald, M.; Christian, Held

    2017-09-01

    The production of irregular shaped deep-drawing parts with high quality requirements, which are common in today’s automotive production, permanently challenges production processes. High requirements on lightweight construction of passenger car bodies following European regulations until 2020 have been massively increasing the use of high strength steels substantially for years and are also leading to bigger challenges in sheet metal part production. Of course, the more and more complex shapes of today’s car body shells also intensify the issue due to modern and future design criteria. The metal forming technology tries to meet these challenges by developing a highly sophisticated layout of deep drawing dies that consider part quality requirements, process robustness and controlled material flow during the deep or stretch drawing process phase. A new method for controlling material flow using a closed loop system was developed at the IFU Stuttgart. In contrast to previous approaches, this new method allows a control intervention during the deep-drawing stroke. The blank holder force around the outline of the drawn part is used as control variable. The closed loop is designed as trajectory follow up with feed forward control. The used command variable is the part-wall stress that is measured with a piezo-electric measuring pin. In this paper the used control loop will be described in detail. The experimental tool that was built for testing the new control approach is explained here with its features. A method for gaining the follow up trajectories from simulation will also be presented. Furthermore, experimental results considering the robustness of the deep drawing process and the gain in process performance with developed control loop will be shown. Finally, a new procedure for the industrial application of the new control method of deep drawing will be presented by using a new kind of active element to influence the local blank holder pressure onto part flange.

  8. Enhancement of Efficiency and Reduction of Grid Thickness Variation on Casting Process with Lean Six Sigma Method

    NASA Astrophysics Data System (ADS)

    Witantyo; Setyawan, David

    2018-03-01

    In a lead acid battery industry, grid casting is a process that has high defect and thickness variation level. DMAIC (Define-Measure-Analyse-Improve-Control) method and its tools will be used to improve the casting process. In the Define stage, it is used project charter and SIPOC (Supplier Input Process Output Customer) method to map the existent problem. In the Measure stage, it is conducted a data retrieval related to the types of defect and the amount of it, also the grid thickness variation that happened. And then the retrieved data is processed and analyzed by using 5 Why’s and FMEA method. In the Analyze stage, it is conducted a grid observation that experience fragile and crack type of defect by using microscope showing the amount of oxide Pb inclusion in the grid. Analysis that is used in grid casting process shows the difference of temperature that is too high between the metal fluid and mold temperature, also the corking process that doesn’t have standard. The Improve stage is conducted a fixing process which generates the reduction of grid variation thickness level and defect/unit level from 9,184% to 0,492%. In Control stage, it is conducted a new working standard determination and already fixed control process.

  9. Method study on fuzzy-PID adaptive control of electric-hydraulic hitch system

    NASA Astrophysics Data System (ADS)

    Li, Mingsheng; Wang, Liubu; Liu, Jian; Ye, Jin

    2017-03-01

    In this paper, fuzzy-PID adaptive control method is applied to the control of tractor electric-hydraulic hitch system. According to the characteristics of the system, a fuzzy-PID adaptive controller is designed and the electric-hydraulic hitch system model is established. Traction control and position control performance simulation are carried out with the common PID control method. A field test rig was set up to test the electric-hydraulic hitch system. The test results showed that, after the fuzzy-PID adaptive control is adopted, when the tillage depth steps from 0.1m to 0.3m, the system transition process time is 4s, without overshoot, and when the tractive force steps from 3000N to 7000N, the system transition process time is 5s, the system overshoot is 25%.

  10. Numerical simulation study on rolling-chemical milling process of aluminum-lithium alloy skin panel

    NASA Astrophysics Data System (ADS)

    Huang, Z. B.; Sun, Z. G.; Sun, X. F.; Li, X. Q.

    2017-09-01

    Single curvature parts such as aircraft fuselage skin panels are usually manufactured by rolling-chemical milling process, which is usually faced with the problem of geometric accuracy caused by springback. In most cases, the methods of manual adjustment and multiple roll bending are used to control or eliminate the springback. However, these methods can cause the increase of product cost and cycle, and lead to material performance degradation. Therefore, it is of significance to precisely control the springback of rolling-chemical milling process. In this paper, using the method of experiment and numerical simulation on rolling-chemical milling process, the simulation model for rolling-chemical milling process of 2060-T8 aluminum-lithium alloy skin was established and testified by the comparison between numerical simulation and experiment results for the validity. Then, based on the numerical simulation model, the relative technological parameters which influence on the curvature of the skin panel were analyzed. Finally, the prediction of springback and the compensation can be realized by controlling the process parameters.

  11. Magnetic agglomeration method for size control in the synthesis of magnetic nanoparticles

    DOEpatents

    Huber, Dale L [Albuquerque, NM

    2011-07-05

    A method for controlling the size of chemically synthesized magnetic nanoparticles that employs magnetic interaction between particles to control particle size and does not rely on conventional kinetic control of the reaction to control particle size. The particles are caused to reversibly agglomerate and precipitate from solution; the size at which this occurs can be well controlled to provide a very narrow particle size distribution. The size of particles is controllable by the size of the surfactant employed in the process; controlling the size of the surfactant allows magnetic control of the agglomeration and precipitation processes. Agglomeration is used to effectively stop particle growth to provide a very narrow range of particle sizes.

  12. The fuzzy algorithm in the die casting mould for the application of multi-channel temperature control

    NASA Astrophysics Data System (ADS)

    Sun, Jin-gen; Chen, Yi; Zhang, Jia-nan

    2017-01-01

    Mould manufacturing is one of the most basic elements in the production chain of China. The mould manufacturing technology has become an important symbol to measure the level of a country's manufacturing industry. The die-casting mould multichannel intelligent temperature control method is studied by cooling water circulation, which uses fuzzy control to realize, aiming at solving the shortcomings of slow speed and big energy consumption during the cooling process of current die-casting mould. At present, the traditional PID control method is used to control the temperature, but it is difficult to ensure the control precision. While , the fuzzy algorithm is used to realize precise control of mould temperature in cooling process. The design is simple, fast response, strong anti-interference ability and good robustness. Simulation results show that the control method is completely feasible, which has higher control precision.

  13. A Process Analytical Technology (PAT) approach to control a new API manufacturing process: development, validation and implementation.

    PubMed

    Schaefer, Cédric; Clicq, David; Lecomte, Clémence; Merschaert, Alain; Norrant, Edith; Fotiadu, Frédéric

    2014-03-01

    Pharmaceutical companies are progressively adopting and introducing Process Analytical Technology (PAT) and Quality-by-Design (QbD) concepts promoted by the regulatory agencies, aiming the building of the quality directly into the product by combining thorough scientific understanding and quality risk management. An analytical method based on near infrared (NIR) spectroscopy was developed as a PAT tool to control on-line an API (active pharmaceutical ingredient) manufacturing crystallization step during which the API and residual solvent contents need to be precisely determined to reach the predefined seeding point. An original methodology based on the QbD principles was designed to conduct the development and validation of the NIR method and to ensure that it is fitted for its intended use. On this basis, Partial least squares (PLS) models were developed and optimized using chemometrics methods. The method was fully validated according to the ICH Q2(R1) guideline and using the accuracy profile approach. The dosing ranges were evaluated to 9.0-12.0% w/w for the API and 0.18-1.50% w/w for the residual methanol. As by nature the variability of the sampling method and the reference method are included in the variability obtained for the NIR method during the validation phase, a real-time process monitoring exercise was performed to prove its fit for purpose. The implementation of this in-process control (IPC) method on the industrial plant from the launch of the new API synthesis process will enable automatic control of the final crystallization step in order to ensure a predefined quality level of the API. In addition, several valuable benefits are expected including reduction of the process time, suppression of a rather difficult sampling and tedious off-line analyses. © 2013 Published by Elsevier B.V.

  14. Method and system for downhole clock synchronization

    DOEpatents

    Hall, David R.; Bartholomew, David B.; Johnson, Monte; Moon, Justin; Koehler, Roger O.

    2006-11-28

    A method and system for use in synchronizing at least two clocks in a downhole network are disclosed. The method comprises determining a total signal latency between a controlling processing element and at least one downhole processing element in a downhole network and sending a synchronizing time over the downhole network to the at least one downhole processing element adjusted for the signal latency. Electronic time stamps may be used to measure latency between processing elements. A system for electrically synchronizing at least two clocks connected to a downhole network comprises a controlling processing element connected to a synchronizing clock in communication over a downhole network with at least one downhole processing element comprising at least one downhole clock. Preferably, the downhole network is integrated into a downhole tool string.

  15. Quality control process improvement of flexible printed circuit board by FMEA

    NASA Astrophysics Data System (ADS)

    Krasaephol, Siwaporn; Chutima, Parames

    2018-02-01

    This research focuses on the quality control process improvement of Flexible Printed Circuit Board (FPCB), centred around model 7-Flex, by using Failure Mode and Effect Analysis (FMEA) method to decrease proportion of defective finished goods that are found at the final inspection process. Due to a number of defective units that were found at the final inspection process, high scraps may be escaped to customers. The problem comes from poor quality control process which is not efficient enough to filter defective products from in-process because there is no In-Process Quality Control (IPQC) or sampling inspection in the process. Therefore, the quality control process has to be improved by setting inspection gates and IPCQs at critical processes in order to filter the defective products. The critical processes are analysed by the FMEA method. IPQC is used for detecting defective products and reducing chances of defective finished goods escaped to the customers. Reducing proportion of defective finished goods also decreases scrap cost because finished goods incur higher scrap cost than work in-process. Moreover, defective products that are found during process can reflect the abnormal processes; therefore, engineers and operators should timely solve the problems. Improved quality control was implemented for 7-Flex production lines from July 2017 to September 2017. The result shows decreasing of the average proportion of defective finished goods and the average of Customer Manufacturers Lot Reject Rate (%LRR of CMs) equal to 4.5% and 4.1% respectively. Furthermore, cost saving of this quality control process equals to 100K Baht.

  16. 21 CFR 820.70 - Production and process controls.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... to ensure that a device conforms to its specifications. Where deviations from device specifications... specifications. Where process controls are needed they shall include: (1) Documented instructions, standard... establish and maintain procedures for changes to a specification, method, process, or procedure. Such...

  17. 21 CFR 820.70 - Production and process controls.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... to ensure that a device conforms to its specifications. Where deviations from device specifications... specifications. Where process controls are needed they shall include: (1) Documented instructions, standard... establish and maintain procedures for changes to a specification, method, process, or procedure. Such...

  18. 76 FR 29767 - Preventive Controls for Registered Human Food and Animal Food/Feed Facilities; Request for Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-23

    ... associated with specific types of food or specific methods of manufacturing, processing, packing, or holding... specific methods of manufacturing, processing, packing, or holding food. In particular, we welcome input on... controls (e.g., procedures and practices utilized to minimize the risk of contamination) for human food and...

  19. Furnace and support equipment for space processing. [space manufacturing - Czochralski method

    NASA Technical Reports Server (NTRS)

    Mazelsky, R.; Duncan, C. S.; Seidensticker, R. G.; Johnson, R. A.; Hopkins, R. H.; Roland, G. W.

    1975-01-01

    A core facility capable of performing a majority of materials processing experiments is discussed. Experiment classes are described, the needs peculiar to each experiment type are outlined, and projected facility requirements to perform the experiments are treated. Control equipment (automatic control) and variations of the Czochralski method for use in space are discussed.

  20. Defining the best quality-control systems by design and inspection.

    PubMed

    Hinckley, C M

    1997-05-01

    Not all of the many approaches to quality control are equally effective. Nonconformities in laboratory testing are caused basically by excessive process variation and mistakes. Statistical quality control can effectively control process variation, but it cannot detect or prevent most mistakes. Because mistakes or blunders are frequently the dominant source of nonconformities, we conclude that statistical quality control by itself is not effective. I explore the 100% inspection methods essential for controlling mistakes. Unlike the inspection techniques that Deming described as ineffective, the new "source" inspection methods can detect mistakes and enable corrections before nonconformities are generated, achieving the highest degree of quality at a fraction of the cost of traditional methods. Key relationships between task complexity and nonconformity rates are also described, along with cultural changes that are essential for implementing the best quality-control practices.

  1. Method of controlling a resin curing process. [for fiber reinforced composites

    NASA Technical Reports Server (NTRS)

    Webster, Charles Neal (Inventor); Scott, Robert O. (Inventor)

    1989-01-01

    The invention relates to an analytical technique for controlling the curing process of fiber-reinforced composite materials that are formed using thermosetting resins. The technique is the percent gel method and involves development of a time-to-gel equation as a function of temperature. From this equation a rate-of-gel equation is then determined, and a percent gel is calculated which is the product of rate-of-gel times time. Percent gel accounting is used to control the proper pressure application point in an autoclave cure process to achieve desired properties in a production composite part.

  2. Controlled decomposition and oxidation: A treatment method for gaseous process effluents

    NASA Technical Reports Server (NTRS)

    Mckinley, Roger J. B., Sr.

    1990-01-01

    The safe disposal of effluent gases produced by the electronics industry deserves special attention. Due to the hazardous nature of many of the materials used, it is essential to control and treat the reactants and reactant by-products as they are exhausted from the process tool and prior to their release into the manufacturing facility's exhaust system and the atmosphere. Controlled decomposition and oxidation (CDO) is one method of treating effluent gases from thin film deposition processes. CDO equipment applications, field experience, and results of the use of CDO equipment and technological advances gained from the field experiences are discussed.

  3. Method and system for controlling a gasification or partial oxidation process

    DOEpatents

    Rozelle, Peter L; Der, Victor K

    2015-02-10

    A method and system for controlling a fuel gasification system includes optimizing a conversion of solid components in the fuel to gaseous fuel components, controlling the flux of solids entrained in the product gas through equipment downstream of the gasifier, and maximizing the overall efficiencies of processes utilizing gasification. A combination of models, when utilized together, can be integrated with existing plant control systems and operating procedures and employed to develop new control systems and operating procedures. Such an approach is further applicable to gasification systems that utilize both dry feed and slurry feed.

  4. Pareto Design of State Feedback Tracking Control of a Biped Robot via Multiobjective PSO in Comparison with Sigma Method and Genetic Algorithms: Modified NSGAII and MATLAB's Toolbox

    PubMed Central

    Mahmoodabadi, M. J.; Taherkhorsandi, M.; Bagheri, A.

    2014-01-01

    An optimal robust state feedback tracking controller is introduced to control a biped robot. In the literature, the parameters of the controller are usually determined by a tedious trial and error process. To eliminate this process and design the parameters of the proposed controller, the multiobjective evolutionary algorithms, that is, the proposed method, modified NSGAII, Sigma method, and MATLAB's Toolbox MOGA, are employed in this study. Among the used evolutionary optimization algorithms to design the controller for biped robots, the proposed method operates better in the aspect of designing the controller since it provides ample opportunities for designers to choose the most appropriate point based upon the design criteria. Three points are chosen from the nondominated solutions of the obtained Pareto front based on two conflicting objective functions, that is, the normalized summation of angle errors and normalized summation of control effort. Obtained results elucidate the efficiency of the proposed controller in order to control a biped robot. PMID:24616619

  5. Parametric synthesis of a robust controller on a base of mathematical programming method

    NASA Astrophysics Data System (ADS)

    Khozhaev, I. V.; Gayvoronskiy, S. A.; Ezangina, T. A.

    2018-05-01

    Considered paper is dedicated to deriving sufficient conditions, linking root indices of robust control quality with coefficients of interval characteristic polynomial, on the base of mathematical programming method. On the base of these conditions, a method of PI- and PID-controllers, providing aperiodic transient process with acceptable stability degree and, subsequently, acceptable setting time, synthesis was developed. The method was applied to a problem of synthesizing a controller for a depth control system of an unmanned underwater vehicle.

  6. 3D Printing Optical Engine for Controlling Material Microstructure

    NASA Astrophysics Data System (ADS)

    Huang, Wei-Chin; Chang, Kuang-Po; Wu, Ping-Han; Wu, Chih-Hsien; Lin, Ching-Chih; Chuang, Chuan-Sheng; Lin, De-Yau; Liu, Sung-Ho; Horng, Ji-Bin; Tsau, Fang-Hei

    Controlling the cooling rate of alloy during melting and resolidification is the most commonly used method for varying the material microstructure and consequently the resuling property. However, the cooling rate of a selective laser melting (SLM) production is restricted by a preset optimal parameter of a good dense product. The head room for locally manipulating material property in a process is marginal. In this study, we invent an Optical Engine for locally controlling material microstructure in a SLM process. It develops an invovative method to control and adjust thermal history of the solidification process to gain desired material microstucture and consequently drastically improving the quality. Process parameters selected locally for specific materials requirement according to designed characteristics by using thermal dynamic principles of solidification process. It utilize a technique of complex laser beam shape of adaptive irradiation profile to permit local control of material characteristics as desired. This technology could be useful for industrial application of medical implant, aerospace and automobile industries.

  7. Six-sigma application in tire-manufacturing company: a case study

    NASA Astrophysics Data System (ADS)

    Gupta, Vikash; Jain, Rahul; Meena, M. L.; Dangayach, G. S.

    2017-09-01

    Globalization, advancement of technologies, and increment in the demand of the customer change the way of doing business in the companies. To overcome these barriers, the six-sigma define-measure-analyze-improve-control (DMAIC) method is most popular and useful. This method helps to trim down the wastes and generating the potential ways of improvement in the process as well as service industries. In the current research, the DMAIC method was used for decreasing the process variations of bead splice causing wastage of material. This six-sigma DMAIC research was initiated by problem identification through voice of customer in the define step. The subsequent step constitutes of gathering the specification data of existing tire bead. This step was followed by the analysis and improvement steps, where the six-sigma quality tools such as cause-effect diagram, statistical process control, and substantial analysis of existing system were implemented for root cause identification and reduction in process variation. The process control charts were used for systematic observation and control the process. Utilizing DMAIC methodology, the standard deviation was decreased from 2.17 to 1.69. The process capability index (C p) value was enhanced from 1.65 to 2.95 and the process performance capability index (C pk) value was enhanced from 0.94 to 2.66. A DMAIC methodology was established that can play a key role for reducing defects in the tire-manufacturing process in India.

  8. Analysis of maizena drying system using temperature control based fuzzy logic method

    NASA Astrophysics Data System (ADS)

    Arief, Ulfah Mediaty; Nugroho, Fajar; Purbawanto, Sugeng; Setyaningsih, Dyah Nurani; Suryono

    2018-03-01

    Corn is one of the rice subtitution food that has good potential. Corn can be processed to be a maizena, and it can be used to make type of food that has been made from maizena, viz. Brownies cake, egg roll, and other cookies. Generally, maizena obtained by drying process carried out 2-3 days under the sun. However, drying process not possible during the rainy season. This drying process can be done using an automatic drying tool. This study was to analyze the design result and manufacture of maizena drying system with temperature control based fuzzylogic method. The result show that temperature of drying system with set point 40°C - 60°C work in suitable condition. The level of water content in 15% (BSN) and temperatureat 50°C included in good drying process. Time required to reach the set point of temperature in 50°C is 7.05 minutes. Drying time for 500 gr samples with temperature 50°C and power capacity 127.6 watt was 1 hour. Based on the result, drying process using temperature control based fuzzy logic method can improve energy efficiency than the conventional method of drying using a direct sunlight source with a temperature that cannot be directly controlled by human being causing the quality of drying result of flour is erratic.

  9. Optimization under variability and uncertainty: a case study for NOx emissions control for a gasification system.

    PubMed

    Chen, Jianjun; Frey, H Christopher

    2004-12-15

    Methods for optimization of process technologies considering the distinction between variability and uncertainty are developed and applied to case studies of NOx control for Integrated Gasification Combined Cycle systems. Existing methods of stochastic optimization (SO) and stochastic programming (SP) are demonstrated. A comparison of SO and SP results provides the value of collecting additional information to reduce uncertainty. For example, an expected annual benefit of 240,000 dollars is estimated if uncertainty can be reduced before a final design is chosen. SO and SP are typically applied to uncertainty. However, when applied to variability, the benefit of dynamic process control is obtained. For example, an annual savings of 1 million dollars could be achieved if the system is adjusted to changes in process conditions. When variability and uncertainty are treated distinctively, a coupled stochastic optimization and programming method and a two-dimensional stochastic programming method are demonstrated via a case study. For the case study, the mean annual benefit of dynamic process control is estimated to be 700,000 dollars, with a 95% confidence range of 500,000 dollars to 940,000 dollars. These methods are expected to be of greatest utility for problems involving a large commitment of resources, for which small differences in designs can produce large cost savings.

  10. Collaborative simulation method with spatiotemporal synchronization process control

    NASA Astrophysics Data System (ADS)

    Zou, Yisheng; Ding, Guofu; Zhang, Weihua; Zhang, Jian; Qin, Shengfeng; Tan, John Kian

    2016-10-01

    When designing a complex mechatronics system, such as high speed trains, it is relatively difficult to effectively simulate the entire system's dynamic behaviors because it involves multi-disciplinary subsystems. Currently,a most practical approach for multi-disciplinary simulation is interface based coupling simulation method, but it faces a twofold challenge: spatial and time unsynchronizations among multi-directional coupling simulation of subsystems. A new collaborative simulation method with spatiotemporal synchronization process control is proposed for coupling simulating a given complex mechatronics system across multiple subsystems on different platforms. The method consists of 1) a coupler-based coupling mechanisms to define the interfacing and interaction mechanisms among subsystems, and 2) a simulation process control algorithm to realize the coupling simulation in a spatiotemporal synchronized manner. The test results from a case study show that the proposed method 1) can certainly be used to simulate the sub-systems interactions under different simulation conditions in an engineering system, and 2) effectively supports multi-directional coupling simulation among multi-disciplinary subsystems. This method has been successfully applied in China high speed train design and development processes, demonstrating that it can be applied in a wide range of engineering systems design and simulation with improved efficiency and effectiveness.

  11. Computer Vision for Artificially Intelligent Robotic Systems

    NASA Astrophysics Data System (ADS)

    Ma, Chialo; Ma, Yung-Lung

    1987-04-01

    In this paper An Acoustic Imaging Recognition System (AIRS) will be introduced which is installed on an Intelligent Robotic System and can recognize different type of Hand tools' by Dynamic pattern recognition. The dynamic pattern recognition is approached by look up table method in this case, the method can save a lot of calculation time and it is practicable. The Acoustic Imaging Recognition System (AIRS) is consist of four parts -- position control unit, pulse-echo signal processing unit, pattern recognition unit and main control unit. The position control of AIRS can rotate an angle of ±5 degree Horizental and Vertical seperately, the purpose of rotation is to find the maximum reflection intensity area, from the distance, angles and intensity of the target we can decide the characteristic of this target, of course all the decision is target, of course all the decision is processed bye the main control unit. In Pulse-Echo Signal Process Unit, we ultilize the correlation method, to overcome the limitation of short burst of ultrasonic, because the Correlation system can transmit large time bandwidth signals and obtain their resolution and increased intensity through pulse compression in the correlation receiver. The output of correlator is sampled and transfer into digital data by u law coding method, and this data together with delay time T, angle information OH, eV will be sent into main control unit for further analysis. The recognition process in this paper, we use dynamic look up table method, in this method at first we shall set up serval recognition pattern table and then the new pattern scanned by Transducer array will be devided into serval stages and compare with the sampling table. The comparison is implemented by dynamic programing and Markovian process. All the hardware control signals, such as optimum delay time for correlator receiver, horizental and vertical rotation angle for transducer plate, are controlled by the Main Control Unit, the Main Control Unit also handles the pattern recognition process. The distance from the target to the transducer plate is limitted by the power and beam angle of transducer elements, in this AIRS Model, we use a narrow beam transducer and it's input voltage is 50V p-p. A RobOt equipped with AIRS can not only measure the distance from the target but also recognize a three dimensional image of target from the image lab of Robot memory. Indexitems, Accoustic System, Supersonic transducer, Dynamic programming, Look-up-table, Image process, pattern Recognition, Quad Tree, Quadappoach.

  12. Improved Performance Characteristics For Indium Antimonide Photovoltaic Detector Arrays Using A FET-Switched Multiplexing Technique

    NASA Astrophysics Data System (ADS)

    Ma, Yung-Lung; Ma, Chialo

    1987-03-01

    In this paper An Acoustic Imaging Recognition System (AIRS) will be introduced which is installed on an Intelligent Robotic System and can recognize different type of Hand tools' by Dynamic pattern recognition. The dynamic pattern recognition is approached by look up table method in this case, the method can save a lot of calculation time and it is practicable. The Acoustic Imaging Recognition System (AIRS) is consist of four parts _ position control unit, pulse-echo signal processing unit, pattern recognition unit and main control unit. The position control of AIRS can rotate an angle of ±5 degree Horizental and Vertical seperately, the purpose of rotation is to find the maximum reflection intensity area, from the distance, angles and intensity of the target we can decide the characteristic of this target, of course all the decision is target, of course all the decision is processed by the main control unit. In Pulse-Echo Signal Process Unit, we utilize the correlation method, to overcome the limitation of short burst of ultrasonic, because the Correlation system can transmit large time bandwidth signals and obtain their resolution and increased intensity through pulse compression in the correlation receiver. The output of correlator is sampled and transfer into digital data by p law coding method, and this data together with delay time T, angle information eH, eV will be sent into main control unit for further analysis. The recognition process in this paper, we use dynamic look up table method, in this method at first we shall set up serval recognition pattern table and then the new pattern scanned by Transducer array will be devided into serval stages and compare with the sampling table. The comparison is implemented by dynamic programing and Markovian process. All the hardware control signals, such as optimum delay time for correlator receiver, horizental and vertical rotation angle for transducer plate, are controlled by the Main Control Unit, the Main Control Unit also handles the pattern recognition process. The distance from the target to the transducer plate is limitted by the power and beam angle of transducer elements, in this AIRS Models, we use a narrow beam transducer and it's input voltage is 50V p-p. A Robot equipped with AIRS can not only measure the distance from the target but also recognize a three dimensional image of target from the image lab of Robot memory. Indexitems, Accoustic System, Supersonic transducer, Dynamic programming, Look-up-table, Image process, pattern Recognition, Quad Tree, Quadappoach.

  13. Fluorescence Spectroscopy and Chemometric Modeling for Bioprocess Monitoring

    PubMed Central

    Faassen, Saskia M.; Hitzmann, Bernd

    2015-01-01

    On-line sensors for the detection of crucial process parameters are desirable for the monitoring, control and automation of processes in the biotechnology, food and pharma industry. Fluorescence spectroscopy as a highly developed and non-invasive technique that enables the on-line measurements of substrate and product concentrations or the identification of characteristic process states. During a cultivation process significant changes occur in the fluorescence spectra. By means of chemometric modeling, prediction models can be calculated and applied for process supervision and control to provide increased quality and the productivity of bioprocesses. A range of applications for different microorganisms and analytes has been proposed during the last years. This contribution provides an overview of different analysis methods for the measured fluorescence spectra and the model-building chemometric methods used for various microbial cultivations. Most of these processes are observed using the BioView® Sensor, thanks to its robustness and insensitivity to adverse process conditions. Beyond that, the PLS-method is the most frequently used chemometric method for the calculation of process models and prediction of process variables. PMID:25942644

  14. Nonlinear Decoupling Control With ANFIS-Based Unmodeled Dynamics Compensation for a Class of Complex Industrial Processes.

    PubMed

    Zhang, Yajun; Chai, Tianyou; Wang, Hong; Wang, Dianhui; Chen, Xinkai

    2018-06-01

    Complex industrial processes are multivariable and generally exhibit strong coupling among their control loops with heavy nonlinear nature. These make it very difficult to obtain an accurate model. As a result, the conventional and data-driven control methods are difficult to apply. Using a twin-tank level control system as an example, a novel multivariable decoupling control algorithm with adaptive neural-fuzzy inference system (ANFIS)-based unmodeled dynamics (UD) compensation is proposed in this paper for a class of complex industrial processes. At first, a nonlinear multivariable decoupling controller with UD compensation is introduced. Different from the existing methods, the decomposition estimation algorithm using ANFIS is employed to estimate the UD, and the desired estimating and decoupling control effects are achieved. Second, the proposed method does not require the complicated switching mechanism which has been commonly used in the literature. This significantly simplifies the obtained decoupling algorithm and its realization. Third, based on some new lemmas and theorems, the conditions on the stability and convergence of the closed-loop system are analyzed to show the uniform boundedness of all the variables. This is then followed by the summary on experimental tests on a heavily coupled nonlinear twin-tank system that demonstrates the effectiveness and the practicability of the proposed method.

  15. Anaerobic digestion of food waste: A review focusing on process stability.

    PubMed

    Li, Lei; Peng, Xuya; Wang, Xiaoming; Wu, Di

    2018-01-01

    Food waste (FW) is rich in biomass energy, and increasing numbers of national programs are being established to recover energy from FW using anaerobic digestion (AD). However process instability is a common operational issue for AD of FW. Process monitoring and control as well as microbial management can be used to control instability and increase the energy conversion efficiency of anaerobic digesters. Here, we review research progress related to these methods and identify existing limitations to efficient AD; recommendations for future research are also discussed. Process monitoring and control are suitable for evaluating the current operational status of digesters, whereas microbial management can facilitate early diagnosis and process optimization. Optimizing and combining these two methods are necessary to improve AD efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Policy-based secure communication with automatic key management for industrial control and automation systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chernoguzov, Alexander; Markham, Thomas R.; Haridas, Harshal S.

    A method includes generating at least one access vector associated with a specified device in an industrial process control and automation system. The specified device has one of multiple device roles. The at least one access vector is generated based on one or more communication policies defining communications between one or more pairs of devices roles in the industrial process control and automation system, where each pair of device roles includes the device role of the specified device. The method also includes providing the at least one access vector to at least one of the specified device and one ormore » more other devices in the industrial process control and automation system in order to control communications to or from the specified device.« less

  17. Distributed systems status and control

    NASA Technical Reports Server (NTRS)

    Kreidler, David; Vickers, David

    1990-01-01

    Concepts are investigated for an automated status and control system for a distributed processing environment. System characteristics, data requirements for health assessment, data acquisition methods, system diagnosis methods and control methods were investigated in an attempt to determine the high-level requirements for a system which can be used to assess the health of a distributed processing system and implement control procedures to maintain an accepted level of health for the system. A potential concept for automated status and control includes the use of expert system techniques to assess the health of the system, detect and diagnose faults, and initiate or recommend actions to correct the faults. Therefore, this research included the investigation of methods by which expert systems were developed for real-time environments and distributed systems. The focus is on the features required by real-time expert systems and the tools available to develop real-time expert systems.

  18. Quality Space and Launch Requirements, Addendum to AS9100C

    DTIC Science & Technology

    2015-05-08

    45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45...SMC Space and Missile Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP...occur without any individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved

  19. Robust iterative learning control for multi-phase batch processes: an average dwell-time method with 2D convergence indexes

    NASA Astrophysics Data System (ADS)

    Wang, Limin; Shen, Yiteng; Yu, Jingxian; Li, Ping; Zhang, Ridong; Gao, Furong

    2018-01-01

    In order to cope with system disturbances in multi-phase batch processes with different dimensions, a hybrid robust control scheme of iterative learning control combined with feedback control is proposed in this paper. First, with a hybrid iterative learning control law designed by introducing the state error, the tracking error and the extended information, the multi-phase batch process is converted into a two-dimensional Fornasini-Marchesini (2D-FM) switched system with different dimensions. Second, a switching signal is designed using the average dwell-time method integrated with the related switching conditions to give sufficient conditions ensuring stable running for the system. Finally, the minimum running time of the subsystems and the control law gains are calculated by solving the linear matrix inequalities. Meanwhile, a compound 2D controller with robust performance is obtained, which includes a robust extended feedback control for ensuring the steady-state tracking error to converge rapidly. The application on an injection molding process displays the effectiveness and superiority of the proposed strategy.

  20. An engineering approach to modelling, decision support and control for sustainable systems.

    PubMed

    Day, W; Audsley, E; Frost, A R

    2008-02-12

    Engineering research and development contributes to the advance of sustainable agriculture both through innovative methods to manage and control processes, and through quantitative understanding of the operation of practical agricultural systems using decision models. This paper describes how an engineering approach, drawing on mathematical models of systems and processes, contributes new methods that support decision making at all levels from strategy and planning to tactics and real-time control. The ability to describe the system or process by a simple and robust mathematical model is critical, and the outputs range from guidance to policy makers on strategic decisions relating to land use, through intelligent decision support to farmers and on to real-time engineering control of specific processes. Precision in decision making leads to decreased use of inputs, less environmental emissions and enhanced profitability-all essential to sustainable systems.

  1. Implementation of hazard analysis and critical control point (HACCP) in dried anchovy production process

    NASA Astrophysics Data System (ADS)

    Citraresmi, A. D. P.; Wahyuni, E. E.

    2018-03-01

    The aim of this study was to inspect the implementation of Hazard Analysis and Critical Control Point (HACCP) for identification and prevention of potential hazards in the production process of dried anchovy at PT. Kelola Mina Laut (KML), Lobuk unit, Sumenep. Cold storage process is needed in each anchovy processing step in order to maintain its physical and chemical condition. In addition, the implementation of quality assurance system should be undertaken to maintain product quality. The research was conducted using a survey method, by following the whole process of making anchovy from the receiving raw materials to the packaging of final product. The method of data analysis used was descriptive analysis method. Implementation of HACCP at PT. KML, Lobuk unit, Sumenep was conducted by applying Pre Requisite Programs (PRP) and preparation stage consisting of 5 initial stages and 7 principles of HACCP. The results showed that CCP was found in boiling process flow with significant hazard of Listeria monocytogenesis bacteria and final sorting process with significant hazard of foreign material contamination in the product. Actions taken were controlling boiling temperature of 100 – 105°C for 3 - 5 minutes and training for sorting process employees.

  2. Quality Space and Launch Requirements Addendum to AS9100C

    DTIC Science & Technology

    2015-03-05

    45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45 8.9.1.1 Out of Control...Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP Standard Repair...individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved techniques and are based on

  3. Quality data collection and management technology of aerospace complex product assembly process

    NASA Astrophysics Data System (ADS)

    Weng, Gang; Liu, Jianhua; He, Yongxi; Zhuang, Cunbo

    2017-04-01

    Aiming at solving problems of difficult management and poor traceability for discrete assembly process quality data, a data collection and management method is proposed which take the assembly process and BOM as the core. Data collection method base on workflow technology, data model base on BOM and quality traceability of assembly process is included in the method. Finally, assembly process quality data management system is developed and effective control and management of quality information for complex product assembly process is realized.

  4. Laser processing for manufacturing nanocarbon materials

    NASA Astrophysics Data System (ADS)

    Van, Hai Hoang

    CNTs have been considered as the excellent candidate to revolutionize a broad range of applications. There have been many method developed to manipulate the chemistry and the structure of CNTs. Laser with non-contact treatment capability exhibits many processing advantages, including solid-state treatment, extremely fast processing rate, and high processing resolution. In addition, the outstanding monochromatic, coherent, and directional beam generates the powerful energy absorption and the resultant extreme processing conditions. In my research, a unique laser scanning method was developed to process CNTs, controlling the oxidation and the graphitization. The achieved controllability of this method was applied to address the important issues of the current CNT processing methods for three applications. The controllable oxidation of CNTs by laser scanning method was applied to cut CNT films to produce high-performance cathodes for FE devices. The production method includes two important self-developed techniques to produce the cold cathodes: the production of highly oriented and uniformly distributed CNT sheets and the precise laser trimming process. Laser cutting is the unique method to produce the cathodes with remarkable features, including ultrathin freestanding structure (~200 nm), greatly high aspect ratio, hybrid CNT-GNR emitter arrays, even emitter separation, and directional emitter alignment. This unique cathode structure was unachievable by other methods. The developed FE devices successfully solved the screening effect issue encounter by current FE devices. The laser-control oxidation method was further developed to sequentially remove graphitic walls of CNTs. The laser oxidation process was directed to occur along the CNT axes by the laser scanning direction. Additionally, the oxidation was further assisted by the curvature stress and the thermal expansion of the graphitic nanotubes, ultimately opening (namely unzipping) the tubular structure to produce GNRs. Therefore the developed laser scanning method optimally exploited the thermal laser-CNT interaction, successfully transforming CNTs into 2D GNRs. The solid-state laser unzipping process effectively addressed the issues of contamination and scalability encountered by the current unzipping methods. Additionally, the produced GNRs were uniquely featured with the freestanding structure and the smooth surfaces. If the scanning process was performed in an inert environment without the appearance of oxygen, the oxidation of CNTs would not happen. Instead, the greatly mobile carbon atoms of the heated CNTs would reorganize the crystal structure, inducing the graphitization process to improve the crystallinity. Many observations showing the structural improvement of CNTs under laser irradiation has been reported, confirming the capability of laser to heal graphitic defects. Laser methods were more time-efficient and energy-efficient than other annealing methods because laser can quickly heat CNTs to generate graphitization in less than one second. This subsecond heating process of laser irradiation was more effective than other heating methods because it avoided the undesired coalescence of CNTs. In my research, the laser scanning method was applied to generate the graphitization, healing the structural defects of CNTs. Different from the reported laser methods, the laser scanning directed the locally annealed areas to move along the CNT axes, migrating and coalescencing the graphitic defects to achieve better healing results. The critical information describing the CNT structural transformation caused by the moving laser irradiation was explored from the successful applications of the developed laser method. This knowledge inspires an important method to modifiy the general graphitic structure for important applications, such as carbon fiber production, CNT self-assembly process and CNT welding. This method will be effective, facile, versatile, and adaptable for laboratory and industrial facilities.

  5. Nonlinear fractional order proportion-integral-derivative active disturbance rejection control method design for hypersonic vehicle attitude control

    NASA Astrophysics Data System (ADS)

    Song, Jia; Wang, Lun; Cai, Guobiao; Qi, Xiaoqiang

    2015-06-01

    Near space hypersonic vehicle model is nonlinear, multivariable and couples in the reentry process, which are challenging for the controller design. In this paper, a nonlinear fractional order proportion integral derivative (NFOPIλDμ) active disturbance rejection control (ADRC) strategy based on a natural selection particle swarm (NSPSO) algorithm is proposed for the hypersonic vehicle flight control. The NFOPIλDμ ADRC method consists of a tracking-differentiator (TD), an NFOPIλDμ controller and an extended state observer (ESO). The NFOPIλDμ controller designed by combining an FOPIλDμ method and a nonlinear states error feedback control law (NLSEF) is to overcome concussion caused by the NLSEF and conversely compensate the insufficiency for relatively simple and rough signal processing caused by the FOPIλDμ method. The TD is applied to coordinate the contradiction between rapidity and overshoot. By attributing all uncertain factors to unknown disturbances, the ESO can achieve dynamic feedback compensation for these disturbances and thus reduce their effects. Simulation results show that the NFOPIλDμ ADRC method can make the hypersonic vehicle six-degree-of-freedom nonlinear model track desired nominal signals accurately and fast, has good stability, dynamic properties and strong robustness against external environmental disturbances.

  6. Real-time control data wrangling for development of mathematical control models of technological processes

    NASA Astrophysics Data System (ADS)

    Vasilyeva, N. V.; Koteleva, N. I.; Fedorova, E. R.

    2018-05-01

    The relevance of the research is due to the need to stabilize the composition of the melting products of copper-nickel sulfide raw materials in the Vanyukov furnace. The goal of this research is to identify the most suitable methods for the aggregation of the real time data for the development of a mathematical model for control of the technological process of melting copper-nickel sulfide raw materials in the Vanyukov furnace. Statistical methods of analyzing the historical data of the real technological object and the correlation analysis of process parameters are described. Factors that exert the greatest influence on the main output parameter (copper content in matte) and ensure the physical-chemical transformations are revealed. An approach to the processing of the real time data for the development of a mathematical model for control of the melting process is proposed. The stages of processing the real time information are considered. The adopted methodology for the aggregation of data suitable for the development of a control model for the technological process of melting copper-nickel sulfide raw materials in the Vanyukov furnace allows us to interpret the obtained results for their further practical application.

  7. Optimal Control of Micro Grid Operation Mode Seamless Switching Based on Radau Allocation Method

    NASA Astrophysics Data System (ADS)

    Chen, Xiaomin; Wang, Gang

    2017-05-01

    The seamless switching process of micro grid operation mode directly affects the safety and stability of its operation. According to the switching process from island mode to grid-connected mode of micro grid, we establish a dynamic optimization model based on two grid-connected inverters. We use Radau allocation method to discretize the model, and use Newton iteration method to obtain the optimal solution. Finally, we implement the optimization mode in MATLAB and get the optimal control trajectory of the inverters.

  8. HDP for the Neutralized pH Value Control in the Clarifying Process of Sugar Cane Juice

    NASA Astrophysics Data System (ADS)

    Lin, Xiaofeng; Yang, Jiaran

    2009-05-01

    Neutralizing pH value of sugar cane juice is the important craft in the control process in the clarifying process of sugar cane juice, which is the important factor to influence output and the quality of white sugar. On the one hand, it is an important content to control the neutralized pH value within a required range, which has the vital significance for acquiring high quality purified juice, reducing energy consumption and raising sucrose recovery. On the other hand, it is a complicated physical-chemistry process, which has the characteristics of strong non-linearity, time-varying, large time-delay, and multi-input. Therefore, there has not been a very good solution to control the neutralized pH value. Firstly, in this chapter, a neural network model for the clarifying process of sugar juice is established based on gathering 1200 groups of real-time sample data in a sugar factory. Then, the HDP (Heuristic Dynamic Programming) method is used to optimize and control the neutralized pH value in the clarifying process of sugar juice. Simulation results indicate that this method has good control effect. This will build a good foundation for stabilizing the clarifying process and enhancing the quality of the purified juice and lastly enhancing the quality of white sugar.

  9. A Novel Hybrid Error Criterion-Based Active Control Method for on-Line Milling Vibration Suppression with Piezoelectric Actuators and Sensors

    PubMed Central

    Zhang, Xingwu; Wang, Chenxi; Gao, Robert X.; Yan, Ruqiang; Chen, Xuefeng; Wang, Shibin

    2016-01-01

    Milling vibration is one of the most serious factors affecting machining quality and precision. In this paper a novel hybrid error criterion-based frequency-domain LMS active control method is constructed and used for vibration suppression of milling processes by piezoelectric actuators and sensors, in which only one Fast Fourier Transform (FFT) is used and no Inverse Fast Fourier Transform (IFFT) is involved. The correction formulas are derived by a steepest descent procedure and the control parameters are analyzed and optimized. Then, a novel hybrid error criterion is constructed to improve the adaptability, reliability and anti-interference ability of the constructed control algorithm. Finally, based on piezoelectric actuators and acceleration sensors, a simulation of a spindle and a milling process experiment are presented to verify the proposed method. Besides, a protection program is added in the control flow to enhance the reliability of the control method in applications. The simulation and experiment results indicate that the proposed method is an effective and reliable way for on-line vibration suppression, and the machining quality can be obviously improved. PMID:26751448

  10. Dream controller

    DOEpatents

    Cheng, George Shu-Xing; Mulkey, Steven L; Wang, Qiang; Chow, Andrew J

    2013-11-26

    A method and apparatus for intelligently controlling continuous process variables. A Dream Controller comprises an Intelligent Engine mechanism and a number of Model-Free Adaptive (MFA) controllers, each of which is suitable to control a process with specific behaviors. The Intelligent Engine can automatically select the appropriate MFA controller and its parameters so that the Dream Controller can be easily used by people with limited control experience and those who do not have the time to commission, tune, and maintain automatic controllers.

  11. Simulation of Simple Controlled Processes with Dead-Time.

    ERIC Educational Resources Information Center

    Watson, Keith R.; And Others

    1985-01-01

    The determination of closed-loop response of processes containing dead-time is typically not covered in undergraduate process control, possibly because the solution by Laplace transforms requires the use of Pade approximation for dead-time, which makes the procedure lengthy and tedious. A computer-aided method is described which simplifies the…

  12. Contamination control in hybrid microelectronic modules. Identification of critical process and contaminants, part 1

    NASA Technical Reports Server (NTRS)

    Himmel, R. P.

    1975-01-01

    Hybrid processes, handling procedures, and materials were examined to identify the critical process steps in which contamination is most likely to occur, to identify the particular contaminants associated with these critical steps, and to propose method for the control of these contaminants.

  13. UAV path planning using artificial potential field method updated by optimal control theory

    NASA Astrophysics Data System (ADS)

    Chen, Yong-bo; Luo, Guan-chen; Mei, Yue-song; Yu, Jian-qiao; Su, Xiao-long

    2016-04-01

    The unmanned aerial vehicle (UAV) path planning problem is an important assignment in the UAV mission planning. Based on the artificial potential field (APF) UAV path planning method, it is reconstructed into the constrained optimisation problem by introducing an additional control force. The constrained optimisation problem is translated into the unconstrained optimisation problem with the help of slack variables in this paper. The functional optimisation method is applied to reform this problem into an optimal control problem. The whole transformation process is deduced in detail, based on a discrete UAV dynamic model. Then, the path planning problem is solved with the help of the optimal control method. The path following process based on the six degrees of freedom simulation model of the quadrotor helicopters is introduced to verify the practicability of this method. Finally, the simulation results show that the improved method is more effective in planning path. In the planning space, the length of the calculated path is shorter and smoother than that using traditional APF method. In addition, the improved method can solve the dead point problem effectively.

  14. Development and testing of controller performance evaluation methodology for multi-input/multi-output digital control systems

    NASA Technical Reports Server (NTRS)

    Pototzky, Anthony; Wieseman, Carol; Hoadley, Sherwood Tiffany; Mukhopadhyay, Vivek

    1991-01-01

    Described here is the development and implementation of on-line, near real time controller performance evaluation (CPE) methods capability. Briefly discussed are the structure of data flow, the signal processing methods used to process the data, and the software developed to generate the transfer functions. This methodology is generic in nature and can be used in any type of multi-input/multi-output (MIMO) digital controller application, including digital flight control systems, digitally controlled spacecraft structures, and actively controlled wind tunnel models. Results of applying the CPE methodology to evaluate (in near real time) MIMO digital flutter suppression systems being tested on the Rockwell Active Flexible Wing (AFW) wind tunnel model are presented to demonstrate the CPE capability.

  15. Controllable laser thermal cleavage of sapphire wafers

    NASA Astrophysics Data System (ADS)

    Xu, Jiayu; Hu, Hong; Zhuang, Changhui; Ma, Guodong; Han, Junlong; Lei, Yulin

    2018-03-01

    Laser processing of substrates for light-emitting diodes (LEDs) offers advantages over other processing techniques and is therefore an active research area in both industrial and academic sectors. The processing of sapphire wafers is problematic because sapphire is a hard and brittle material. Semiconductor laser scribing processing suffers certain disadvantages that have yet to be overcome, thereby necessitating further investigation. In this work, a platform for controllable laser thermal cleavage was constructed. A sapphire LED wafer was modeled using the finite element method to simulate the thermal and stress distributions under different conditions. A guide groove cut by laser ablation before the cleavage process was observed to guide the crack extension and avoid deviation. The surface and cross section of sapphire wafers processed using controllable laser thermal cleavage were characterized by scanning electron microscopy and optical microscopy, and their morphology was compared to that of wafers processed using stealth dicing. The differences in luminous efficiency between substrates prepared using these two processing methods are explained.

  16. Knowledge-based processing for aircraft flight control

    NASA Technical Reports Server (NTRS)

    Painter, John H.; Glass, Emily; Economides, Gregory; Russell, Paul

    1994-01-01

    This Contractor Report documents research in Intelligent Control using knowledge-based processing in a manner dual to methods found in the classic stochastic decision, estimation, and control discipline. Such knowledge-based control has also been called Declarative, and Hybid. Software architectures were sought, employing the parallelism inherent in modern object-oriented modeling and programming. The viewpoint adopted was that Intelligent Control employs a class of domain-specific software architectures having features common over a broad variety of implementations, such as management of aircraft flight, power distribution, etc. As much attention was paid to software engineering issues as to artificial intelligence and control issues. This research considered that particular processing methods from the stochastic and knowledge-based worlds are duals, that is, similar in a broad context. They provide architectural design concepts which serve as bridges between the disparate disciplines of decision, estimation, control, and artificial intelligence. This research was applied to the control of a subsonic transport aircraft in the airport terminal area.

  17. Asymptotically suboptimal control of weakly interconnected dynamical systems

    NASA Astrophysics Data System (ADS)

    Dmitruk, N. M.; Kalinin, A. I.

    2016-10-01

    Optimal control problems for a group of systems with weak dynamical interconnections between its constituent subsystems are considered. A method for decentralized control is proposed which distributes the control actions between several controllers calculating in real time control inputs only for theirs subsystems based on the solution of the local optimal control problem. The local problem is solved by asymptotic methods that employ the representation of the weak interconnection by a small parameter. Combination of decentralized control and asymptotic methods allows to significantly reduce the dimension of the problems that have to be solved in the course of the control process.

  18. Automated plasma control with optical emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Ward, P. P.

    Plasma etching and desmear processes for printed wiring board (PWB) manufacture are difficult to predict and control. Non-uniformity of most plasma processes and sensitivity to environmental changes make it difficult to maintain process stability from day to day. To assure plasma process performance, weight loss coupons or post-plasma destructive testing must be used. These techniques are not real-time methods however, and do not allow for immediate diagnosis and process correction. These tests often require scrapping some fraction of a batch to insure the integrity of the rest. Since these tests verify a successful cycle with post-plasma diagnostics, poor test results often determine that a batch is substandard and the resulting parts unusable. These tests are a costly part of the overall fabrication cost. A more efficient method of testing would allow for constant monitoring of plasma conditions and process control. Process anomalies should be detected and corrected before the parts being treated are damaged. Real time monitoring would allow for instantaneous corrections. Multiple site monitoring would allow for process mapping within one system or simultaneous monitoring of multiple systems. Optical emission spectroscopy conducted external to the plasma apparatus would allow for this sort of multifunctional analysis without perturbing the glow discharge. In this paper, optical emission spectroscopy for non-intrusive, in situ process control will be explored along with applications of this technique to for process control, failure analysis and endpoint determination in PWB manufacture.

  19. The research of laser marking control technology

    NASA Astrophysics Data System (ADS)

    Zhang, Qiue; Zhang, Rong

    2009-08-01

    In the area of Laser marking, the general control method is insert control card to computer's mother board, it can not support hot swap, it is difficult to assemble or it. Moreover, the one marking system must to equip one computer. In the system marking, the computer can not to do the other things except to transmit marking digital information. Otherwise it can affect marking precision. Based on traditional control methods existed some problems, introduced marking graphic editing and digital processing by the computer finish, high-speed digital signal processor (DSP) control marking the whole process. The laser marking controller is mainly contain DSP2812, digital memorizer, DAC (digital analog converting) transform unit circuit, USB interface control circuit, man-machine interface circuit, and other logic control circuit. Download the marking information which is processed by computer to U disk, DSP read the information by USB interface on time, then processing it, adopt the DSP inter timer control the marking time sequence, output the scanner control signal by D/A parts. Apply the technology can realize marking offline, thereby reduce the product cost, increase the product efficiency. The system have good effect in actual unit markings, the marking speed is more quickly than PCI control card to 20 percent. It has application value in practicality.

  20. A Method for Implementing Force-Limited Vibration Control

    NASA Technical Reports Server (NTRS)

    Worth, Daniel B.

    1997-01-01

    NASA/GSFC has implemented force-limited vibration control on a controller which can only accept one profile. The method uses a personal computer based digital signal processing board to convert force and/or moment signals into what appears to he an acceleration signal to the controller. This technique allows test centers with older controllers to use the latest force-limited control techniques for random vibration testing. The paper describes the method, hardware, and test procedures used. An example from a test performed at NASA/GSFC is used as a guide.

  1. Image processing methods in two and three dimensions used to animate remotely sensed data. [cloud cover

    NASA Technical Reports Server (NTRS)

    Hussey, K. J.; Hall, J. R.; Mortensen, R. A.

    1986-01-01

    Image processing methods and software used to animate nonimaging remotely sensed data on cloud cover are described. Three FORTRAN programs were written in the VICAR2/TAE image processing domain to perform 3D perspective rendering, to interactively select parameters controlling the projection, and to interpolate parameter sets for animation images between key frames. Operation of the 3D programs and transferring the images to film is automated using executive control language and custom hardware to link the computer and camera.

  2. Active disturbance rejection controller for chemical reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro

    2015-03-10

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However themore » resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.« less

  3. The influence of processing on the microbial risk associated with Rooibos (Aspalathus linearis) tea.

    PubMed

    Gouws, Pieter; Hartel, Toni; van Wyk, Rudean

    2014-12-01

    This review discusses the influence of processing on the microbial risk associated with Salmonella in Rooibos tea, the identification of Salmonella and preventative and control measures to control microbial contamination. Rooibos tea, like other plant products, naturally contains a high microbial load. Downstream processing steps of these products usually help in reducing any contaminants present. Due to the delicate flavour properties and nature of Rooibos, gentle processing techniques are necessary for the production of good quality tea. However, this has a major influence on the microbiological status of the product. The presence of Salmonella in Rooibos is poorly understood. The ubiquitous distribution of Salmonella in the natural environment and its prevalence in the global food chain, the physiological adaptability, virulence of the bacterial pathogen and its serious economic impact on the food industry, emphasises the need for continued awareness and stringent controls at all levels of food production. With the advances of technology and information at hand, the processing of Rooibos needs to be re-evaluated. Since the delicate nature of Rooibos prohibits the use of harsh methods to control Salmonella, alternative methods for the steam pasteurisation of Rooibos show great potential to control Salmonella in a fast, efficient and cost-effective manner. These alternative methods will significantly improve the microbiological quality of Rooibos and provide a product that is safe to consumers. © 2014 Society of Chemical Industry.

  4. Statistical Methods in Assembly Quality Management of Multi-Element Products on Automatic Rotor Lines

    NASA Astrophysics Data System (ADS)

    Pries, V. V.; Proskuriakov, N. E.

    2018-04-01

    To control the assembly quality of multi-element mass-produced products on automatic rotor lines, control methods with operational feedback are required. However, due to possible failures in the operation of the devices and systems of automatic rotor line, there is always a real probability of getting defective (incomplete) products into the output process stream. Therefore, a continuous sampling control of the products completeness, based on the use of statistical methods, remains an important element in managing the quality of assembly of multi-element mass products on automatic rotor lines. The feature of continuous sampling control of the multi-element products completeness in the assembly process is its breaking sort, which excludes the possibility of returning component parts after sampling control to the process stream and leads to a decrease in the actual productivity of the assembly equipment. Therefore, the use of statistical procedures for continuous sampling control of the multi-element products completeness when assembled on automatic rotor lines requires the use of such sampling plans that ensure a minimum size of control samples. Comparison of the values of the limit of the average output defect level for the continuous sampling plan (CSP) and for the automated continuous sampling plan (ACSP) shows the possibility of providing lower limit values for the average output defects level using the ACSP-1. Also, the average sample size when using the ACSP-1 plan is less than when using the CSP-1 plan. Thus, the application of statistical methods in the assembly quality management of multi-element products on automatic rotor lines, involving the use of proposed plans and methods for continuous selective control, will allow to automating sampling control procedures and the required level of quality of assembled products while minimizing sample size.

  5. Root Cause Analysis of Quality Defects Using HPLC-MS Fingerprint Knowledgebase for Batch-to-batch Quality Control of Herbal Drugs.

    PubMed

    Yan, Binjun; Fang, Zhonghua; Shen, Lijuan; Qu, Haibin

    2015-01-01

    The batch-to-batch quality consistency of herbal drugs has always been an important issue. To propose a methodology for batch-to-batch quality control based on HPLC-MS fingerprints and process knowledgebase. The extraction process of Compound E-jiao Oral Liquid was taken as a case study. After establishing the HPLC-MS fingerprint analysis method, the fingerprints of the extract solutions produced under normal and abnormal operation conditions were obtained. Multivariate statistical models were built for fault detection and a discriminant analysis model was built using the probabilistic discriminant partial-least-squares method for fault diagnosis. Based on multivariate statistical analysis, process knowledge was acquired and the cause-effect relationship between process deviations and quality defects was revealed. The quality defects were detected successfully by multivariate statistical control charts and the type of process deviations were diagnosed correctly by discriminant analysis. This work has demonstrated the benefits of combining HPLC-MS fingerprints, process knowledge and multivariate analysis for the quality control of herbal drugs. Copyright © 2015 John Wiley & Sons, Ltd.

  6. Sensor fault-tolerant control for gear-shifting engaging process of automated manual transmission

    NASA Astrophysics Data System (ADS)

    Li, Liang; He, Kai; Wang, Xiangyu; Liu, Yahui

    2018-01-01

    Angular displacement sensor on the actuator of automated manual transmission (AMT) is sensitive to fault, and the sensor fault will disturb its normal control, which affects the entire gear-shifting process of AMT and results in awful riding comfort. In order to solve this problem, this paper proposes a method of fault-tolerant control for AMT gear-shifting engaging process. By using the measured current of actuator motor and angular displacement of actuator, the gear-shifting engaging load torque table is built and updated before the occurrence of the sensor fault. Meanwhile, residual between estimated and measured angular displacements is used to detect the sensor fault. Once the residual exceeds a determined fault threshold, the sensor fault is detected. Then, switch control is triggered, and the current observer and load torque table estimates an actual gear-shifting position to replace the measured one to continue controlling the gear-shifting process. Numerical and experiment tests are carried out to evaluate the reliability and feasibility of proposed methods, and the results show that the performance of estimation and control is satisfactory.

  7. New S control chart using skewness correction method for monitoring process dispersion of skewed distributions

    NASA Astrophysics Data System (ADS)

    Atta, Abdu; Yahaya, Sharipah; Zain, Zakiyah; Ahmed, Zalikha

    2017-11-01

    Control chart is established as one of the most powerful tools in Statistical Process Control (SPC) and is widely used in industries. The conventional control charts rely on normality assumption, which is not always the case for industrial data. This paper proposes a new S control chart for monitoring process dispersion using skewness correction method for skewed distributions, named as SC-S control chart. Its performance in terms of false alarm rate is compared with various existing control charts for monitoring process dispersion, such as scaled weighted variance S chart (SWV-S); skewness correction R chart (SC-R); weighted variance R chart (WV-R); weighted variance S chart (WV-S); and standard S chart (STD-S). Comparison with exact S control chart with regards to the probability of out-of-control detections is also accomplished. The Weibull and gamma distributions adopted in this study are assessed along with the normal distribution. Simulation study shows that the proposed SC-S control chart provides good performance of in-control probabilities (Type I error) in almost all the skewness levels and sample sizes, n. In the case of probability of detection shift the proposed SC-S chart is closer to the exact S control chart than the existing charts for skewed distributions, except for the SC-R control chart. In general, the performance of the proposed SC-S control chart is better than all the existing control charts for monitoring process dispersion in the cases of Type I error and probability of detection shift.

  8. Testing of the Defense Waste Processing Facility Cold Chemical Dissolution Method in Sludge Batch 9 Qualification

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edwards, T.; Pareizs, J.; Coleman, C.

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) tests the applicability of the digestion methods used by the DWPF Laboratory for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) Receipt samples and SRAT Product process control samples. DWPF SRAT samples are typically dissolved using a method referred to as the DWPF Cold Chemical or Cold Chem Method (CC), (see DWPF Procedure SW4- 15.201). Testing indicates that the CC method produced mixed results. The CC method did not result in complete dissolution of either the SRAT Receipt ormore » SRAT Product with some fine, dark solids remaining. However, elemental analyses did not reveal extreme biases for the major elements in the sludge when compared with analyses obtained following dissolution by hot aqua regia (AR) or sodium peroxide fusion (PF) methods. The CC elemental analyses agreed with the AR and PF methods well enough that it should be adequate for routine process control analyses in the DWPF after much more extensive side-by-side tests of the CC method and the PF method are performed on the first 10 SRAT cycles of the Sludge Batch 9 (SB9) campaign. The DWPF Laboratory should continue with their plans for further tests of the CC method during these 10 SRAT cycles.« less

  9. Digital Signal Processing and Control for the Study of Gene Networks

    NASA Astrophysics Data System (ADS)

    Shin, Yong-Jun

    2016-04-01

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks.

  10. Digital Signal Processing and Control for the Study of Gene Networks.

    PubMed

    Shin, Yong-Jun

    2016-04-22

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks.

  11. Digital Signal Processing and Control for the Study of Gene Networks

    PubMed Central

    Shin, Yong-Jun

    2016-01-01

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks. PMID:27102828

  12. Highly Controlled Codeposition Rate of Organolead Halide Perovskite by Laser Evaporation Method.

    PubMed

    Miyadera, Tetsuhiko; Sugita, Takeshi; Tampo, Hitoshi; Matsubara, Koji; Chikamatsu, Masayuki

    2016-10-05

    Organolead-halide perovskites can be promising materials for next-generation solar cells because of its high power conversion efficiency. The method of precise fabrication is required because both solution-process and vacuum-process fabrication of the perovskite have problems of controllability and reproducibility. Vacuum deposition process was expected to achieve precise control; however, vaporization of amine compound significantly degrades the controllability of deposition rate. Here we achieved the reduction of the vaporization by implementing the laser evaporation system for the codeposition of perovskite. Locally irradiated continuous-wave lasers on the source materials realized the reduced vaporization of CH 3 NH 3 I. The deposition rate was stabilized for several hours by adjusting the duty ratio of modulated laser based on proportional-integral control. Organic-photovoltaic-type perovskite solar cells were fabricated by codeposition of PbI 2 and CH 3 NH 3 I. A power-conversion efficiency of 16.0% with reduced hysteresis was achieved.

  13. Dual RBFNNs-Based Model-Free Adaptive Control With Aspen HYSYS Simulation.

    PubMed

    Zhu, Yuanming; Hou, Zhongsheng; Qian, Feng; Du, Wenli

    2017-03-01

    In this brief, we propose a new data-driven model-free adaptive control (MFAC) method with dual radial basis function neural networks (RBFNNs) for a class of discrete-time nonlinear systems. The main novelty lies in that it provides a systematic design method for controller structure by the direct usage of I/O data, rather than using the first-principle model or offline identified plant model. The controller structure is determined by equivalent-dynamic-linearization representation of the ideal nonlinear controller, and the controller parameters are tuned by the pseudogradient information extracted from the I/O data of the plant, which can deal with the unknown nonlinear system. The stability of the closed-loop control system and the stability of the training process for RBFNNs are guaranteed by rigorous theoretical analysis. Meanwhile, the effectiveness and the applicability of the proposed method are further demonstrated by the numerical example and Aspen HYSYS simulation of distillation column in crude styrene produce process.

  14. Compound semi-conductors and controlled doping thereof

    NASA Technical Reports Server (NTRS)

    Larkin, David J. (Inventor); Neudeck, Philip G. (Inventor); Powell, J. Anthony (Inventor); Matus, Lawrence G. (Inventor)

    1998-01-01

    A method of controlling the amount of impurity incorporation in a crystal grown by a chemical vapor deposition process. Conducted in a growth chamber, the method includes the controlling of the concentration of the crystal growing components in the growth chamber to affect the demand of particular growth sites within the growing crystal thereby controlling impurity incorporation into the growth sites.

  15. Engineering Change Management Method Framework in Mechanical Engineering

    NASA Astrophysics Data System (ADS)

    Stekolschik, Alexander

    2016-11-01

    Engineering changes make an impact on different process chains in and outside the company, and lead to most error costs and time shifts. In fact, 30 to 50 per cent of development costs result from technical changes. Controlling engineering change processes can help us to avoid errors and risks, and contribute to cost optimization and a shorter time to market. This paper presents a method framework for controlling engineering changes at mechanical engineering companies. The developed classification of engineering changes and accordingly process requirements build the basis for the method framework. The developed method framework comprises two main areas: special data objects managed in different engineering IT tools and process framework. Objects from both areas are building blocks that can be selected to the overall business process based on the engineering process type and change classification. The process framework contains steps for the creation of change objects (both for overall change and for parts), change implementation, and release. Companies can select singleprocess building blocks from the framework, depending on the product development process and change impact. The developed change framework has been implemented at a division (10,000 employees) of a big German mechanical engineering company.

  16. Online low-field NMR spectroscopy for process control of an industrial lithiation reaction-automated data analysis.

    PubMed

    Kern, Simon; Meyer, Klas; Guhl, Svetlana; Gräßer, Patrick; Paul, Andrea; King, Rudibert; Maiwald, Michael

    2018-05-01

    Monitoring specific chemical properties is the key to chemical process control. Today, mainly optical online methods are applied, which require time- and cost-intensive calibration effort. NMR spectroscopy, with its advantage being a direct comparison method without need for calibration, has a high potential for enabling closed-loop process control while exhibiting short set-up times. Compact NMR instruments make NMR spectroscopy accessible in industrial and rough environments for process monitoring and advanced process control strategies. We present a fully automated data analysis approach which is completely based on physically motivated spectral models as first principles information (indirect hard modeling-IHM) and applied it to a given pharmaceutical lithiation reaction in the framework of the European Union's Horizon 2020 project CONSENS. Online low-field NMR (LF NMR) data was analyzed by IHM with low calibration effort, compared to a multivariate PLS-R (partial least squares regression) approach, and both validated using online high-field NMR (HF NMR) spectroscopy. Graphical abstract NMR sensor module for monitoring of the aromatic coupling of 1-fluoro-2-nitrobenzene (FNB) with aniline to 2-nitrodiphenylamine (NDPA) using lithium-bis(trimethylsilyl) amide (Li-HMDS) in continuous operation. Online 43.5 MHz low-field NMR (LF) was compared to 500 MHz high-field NMR spectroscopy (HF) as reference method.

  17. On-Board Real-Time Optimization Control for Turbo-Fan Engine Life Extending

    NASA Astrophysics Data System (ADS)

    Zheng, Qiangang; Zhang, Haibo; Miao, Lizhen; Sun, Fengyong

    2017-11-01

    A real-time optimization control method is proposed to extend turbo-fan engine service life. This real-time optimization control is based on an on-board engine mode, which is devised by a MRR-LSSVR (multi-input multi-output recursive reduced least squares support vector regression method). To solve the optimization problem, a FSQP (feasible sequential quadratic programming) algorithm is utilized. The thermal mechanical fatigue is taken into account during the optimization process. Furthermore, to describe the engine life decaying, a thermal mechanical fatigue model of engine acceleration process is established. The optimization objective function not only contains the sub-item which can get fast response of the engine, but also concludes the sub-item of the total mechanical strain range which has positive relationship to engine fatigue life. Finally, the simulations of the conventional optimization control which just consider engine acceleration performance or the proposed optimization method have been conducted. The simulations demonstrate that the time of the two control methods from idle to 99.5 % of the maximum power are equal. However, the engine life using the proposed optimization method could be surprisingly increased by 36.17 % compared with that using conventional optimization control.

  18. Controlled Expansion of Supercritical Solution: A Robust Method to Produce Pure Drug Nanoparticles With Narrow Size-Distribution.

    PubMed

    Pessi, Jenni; Lassila, Ilkka; Meriläinen, Antti; Räikkönen, Heikki; Hæggström, Edward; Yliruusi, Jouko

    2016-08-01

    We introduce a robust, stable, and reproducible method to produce nanoparticles based on expansion of supercritical solutions using carbon dioxide as a solvent. The method, controlled expansion of supercritical solution (CESS), uses controlled mass transfer, flow, pressure reduction, and particle collection in dry ice. CESS offers control over the crystallization process as the pressure in the system is reduced according to a specific profile. Particle formation takes place before the exit nozzle, and condensation is the main mechanism for postnucleation particle growth. A 2-step gradient pressure reduction is used to prevent Mach disk formation and particle growth by coagulation. Controlled particle growth keeps the production process stable. With CESS, we produced piroxicam nanoparticles, 60 mg/h, featuring narrow size distribution (176 ± 53 nm). Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  19. Emerging non-invasive Raman methods in process control and forensic applications.

    PubMed

    Macleod, Neil A; Matousek, Pavel

    2008-10-01

    This article reviews emerging Raman techniques (Spatially Offset and Transmission Raman Spectroscopy) for non-invasive, sub-surface probing in process control and forensic applications. New capabilities offered by these methods are discussed and several application examples are given including the non-invasive detection of counterfeit drugs through blister packs and opaque plastic bottles and the rapid quantitative analysis of the bulk content of pharmaceutical tablets and capsules without sub-sampling.

  20. A Course in... Multivariable Control Methods.

    ERIC Educational Resources Information Center

    Deshpande, Pradeep B.

    1988-01-01

    Describes an engineering course for graduate study in process control. Lists four major topics: interaction analysis, multiloop controller design, decoupling, and multivariable control strategies. Suggests a course outline and gives information about each topic. (MVL)

  1. Improved design of constrained model predictive tracking control for batch processes against unknown uncertainties.

    PubMed

    Wu, Sheng; Jin, Qibing; Zhang, Ridong; Zhang, Junfeng; Gao, Furong

    2017-07-01

    In this paper, an improved constrained tracking control design is proposed for batch processes under uncertainties. A new process model that facilitates process state and tracking error augmentation with further additional tuning is first proposed. Then a subsequent controller design is formulated using robust stable constrained MPC optimization. Unlike conventional robust model predictive control (MPC), the proposed method enables the controller design to bear more degrees of tuning so that improved tracking control can be acquired, which is very important since uncertainties exist inevitably in practice and cause model/plant mismatches. An injection molding process is introduced to illustrate the effectiveness of the proposed MPC approach in comparison with conventional robust MPC. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Unsedation colonoscopy can be not that painful: Evaluation of the effect of "Lamaze method of colonoscopy".

    PubMed

    Yu, Shao-Ping; Lin, Xiao-Dong; Wu, Guang-Yao; Li, Song-Hu; Wen, Zong-Quan; Cen, Xiao-Hong; Huang, Xian-Guang; Huang, Mei-Ting

    2015-10-25

    To evaluate the pain relieving effect of intervention with "Lamaze method of colonoscopy" in the process of colonoscopy. Five hundred and eighty-five patients underwent colonoscopy were randomly divided into three groups, Lamaze group, anesthetic group and control group. Two hundred and twenty-four patients of Lamaze group, the "Lamaze method of colonoscopy" were practiced in the process of colonoscopy. The Lamaze method of colonoscopy is modified from the Lamaze method of childbirth, which helped patients to relieve pain through effective breathing control. One hundred and seventy-eight patients in anesthetic group accepted sedation colonoscopy. For 183 patients in control group, colonoscopy was performed without any intervention. The satisfactory of colon cleaning, intestinal lesions, intubation time, success ratio, pain grading and complications were recorded. All data were statistically analyzed. There were no significant differences at base line of the three groups (P > 0.05). Anesthetic group shows advantage in intubation time than the other two groups (P < 0.05). Lamaze group shows no advantage in intubation time than that in control group (P > 0.05). The anesthetic group showed an apparent advantage in relieving pain (P < 0.01). Therefore, the "Lamaze method of colonoscopy" performed in colonoscopy could relieve pain effectively comparing with control group (P < 0.05). The patients in anesthetic group had the highest incidence of complications (P < 0.05). The performance of the "Lamaze method of colonoscopy" in the process of colonoscopy could relieve patients' pain, minimize the incidence of complications, and is worthy promotion in clinical practice.

  3. [Discussion on Quality Evaluation Method of Medical Device During Life-Cycle in Operation Based on the Analytic Hierarchy Process].

    PubMed

    Zheng, Caixian; Zheng, Kun; Shen, Yunming; Wu, Yunyun

    2016-01-01

    The content related to the quality during life-cycle in operation of medical device includes daily use, repair volume, preventive maintenance, quality control and adverse event monitoring. In view of this, the article aims at discussion on the quality evaluation method of medical devices during their life cycle in operation based on the Analytic Hierarchy Process (AHP). The presented method is proved to be effective by evaluating patient monitors as example. The method presented in can promote and guide the device quality control work, and it can provide valuable inputs to decisions about purchase of new device.

  4. Adaptive identification and control of structural dynamics systems using recursive lattice filters

    NASA Technical Reports Server (NTRS)

    Sundararajan, N.; Montgomery, R. C.; Williams, J. P.

    1985-01-01

    A new approach for adaptive identification and control of structural dynamic systems by using least squares lattice filters thar are widely used in the signal processing area is presented. Testing procedures for interfacing the lattice filter identification methods and modal control method for stable closed loop adaptive control are presented. The methods are illustrated for a free-free beam and for a complex flexible grid, with the basic control objective being vibration suppression. The approach is validated by using both simulations and experimental facilities available at the Langley Research Center.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Britten, J

    WET-ETCH FIGURING (WEF) is an automated method of precisely figuring optical materials by the controlled application of aqueous etchant solution. This technology uses surface-tension-gradient-driven flow to confine and stabilize a wetted zone of an etchant solution or other aqueous processing fluid on the surface of an object. This wetted zone can be translated on the surface in a computer-controlled fashion for precise spatial control of the surface reactions occurring (e.g. chemical etching). WEF is particularly suitable for figuring very thin optical materials because it applies no thermal or mechanical stress to the material. Also, because the process is stress-free themore » workpiece can be monitored during figuring using interferometric metrology, and the measurements obtained can be used to control the figuring process in real-time--something that cannot be done with traditional figuring methods.« less

  6. Observation method to predict meander migration and vertical degradation of rivers.

    DOT National Transportation Integrated Search

    2014-05-01

    Meander migration and vertical degradation of river bed are processes that have been studied for years. : Different methods have been proposed to make predictions of the behavior of rivers with respect to these : processes. These two erosion controll...

  7. Coordinated control of active and reactive power of distribution network with distributed PV cluster via model predictive control

    NASA Astrophysics Data System (ADS)

    Ji, Yu; Sheng, Wanxing; Jin, Wei; Wu, Ming; Liu, Haitao; Chen, Feng

    2018-02-01

    A coordinated optimal control method of active and reactive power of distribution network with distributed PV cluster based on model predictive control is proposed in this paper. The method divides the control process into long-time scale optimal control and short-time scale optimal control with multi-step optimization. The models are transformed into a second-order cone programming problem due to the non-convex and nonlinear of the optimal models which are hard to be solved. An improved IEEE 33-bus distribution network system is used to analyse the feasibility and the effectiveness of the proposed control method

  8. Method and apparatus for decoupled thermo-catalytic pollution control

    DOEpatents

    Tabatabaie-Raissi, Ali; Muradov, Nazim Z.; Martin, Eric

    2006-07-11

    A new method for design and scale-up of thermocatalytic processes is disclosed. The method is based on optimizing process energetics by decoupling of the process energetics from the DRE for target contaminants. The technique is applicable to high temperature thermocatalytic reactor design and scale-up. The method is based on the implementation of polymeric and other low-pressure drop support for thermocatalytic media as well as the multifunctional catalytic media in conjunction with a novel rotating fluidized particle bed reactor.

  9. A System-Oriented Approach for the Optimal Control of Process Chains under Stochastic Influences

    NASA Astrophysics Data System (ADS)

    Senn, Melanie; Schäfer, Julian; Pollak, Jürgen; Link, Norbert

    2011-09-01

    Process chains in manufacturing consist of multiple connected processes in terms of dynamic systems. The properties of a product passing through such a process chain are influenced by the transformation of each single process. There exist various methods for the control of individual processes, such as classical state controllers from cybernetics or function mapping approaches realized by statistical learning. These controllers ensure that a desired state is obtained at process end despite of variations in the input and disturbances. The interactions between the single processes are thereby neglected, but play an important role in the optimization of the entire process chain. We divide the overall optimization into two phases: (1) the solution of the optimization problem by Dynamic Programming to find the optimal control variable values for each process for any encountered end state of its predecessor and (2) the application of the optimal control variables at runtime for the detected initial process state. The optimization problem is solved by selecting adequate control variables for each process in the chain backwards based on predefined quality requirements for the final product. For the demonstration of the proposed concept, we have chosen a process chain from sheet metal manufacturing with simplified transformation functions.

  10. Design of a Single-Cell Positioning Controller Using Electroosmotic Flow and Image Processing

    PubMed Central

    Ay, Chyung; Young, Chao-Wang; Chen, Jhong-Yin

    2013-01-01

    The objective of the current research was not only to provide a fast and automatic positioning platform for single cells, but also improved biomolecular manipulation techniques. In this study, an automatic platform for cell positioning using electroosmotic flow and image processing technology was designed. The platform was developed using a PCI image acquisition interface card for capturing images from a microscope and then transferring them to a computer using human-machine interface software. This software was designed by the Laboratory Virtual Instrument Engineering Workbench, a graphical language for finding cell positions and viewing the driving trace, and the fuzzy logic method for controlling the voltage or time of an electric field. After experiments on real human leukemic cells (U-937), the success of the cell positioning rate achieved by controlling the voltage factor reaches 100% within 5 s. A greater precision is obtained when controlling the time factor, whereby the success rate reaches 100% within 28 s. Advantages in both high speed and high precision are attained if these two voltage and time control methods are combined. The control speed with the combined method is about 5.18 times greater than that achieved by the time method, and the control precision with the combined method is more than five times greater than that achieved by the voltage method. PMID:23698272

  11. 40 CFR 64.1 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... contain, capture and transport a pollutant to a control device. Continuous compliance determination method..., boilers or process heaters). For purposes of this part, a control device does not include passive control...

  12. Multi-laboratory survey of qPCR enterococci analysis method performance

    EPA Pesticide Factsheets

    Quantitative polymerase chain reaction (qPCR) has become a frequently used technique for quantifying enterococci in recreational surface waters, but there are several methodological options. Here we evaluated how three method permutations, type of mastermix, sample extract dilution and use of controls in results calculation, affect method reliability among multiple laboratories with respect to sample interference. Multiple samples from each of 22 sites representing an array of habitat types were analyzed using EPA Method 1611 and 1609 reagents with full strength and five-fold diluted extracts. The presence of interference was assessed three ways: using sample processing and PCR amplifications controls; consistency of results across extract dilutions; and relative recovery of target genes from spiked enterococci in water sample compared to control matrices with acceptable recovery defined as 50 to 200%. Method 1609, which is based on an environmental mastermix, was found to be superior to Method 1611, which is based on a universal mastermix. Method 1611 had over a 40% control assay failure rate with undiluted extracts and a 6% failure rate with diluted extracts. Method 1609 failed in only 11% and 3% of undiluted and diluted extracts analyses. Use of sample processing control assay results in the delta-delta Ct method for calculating relative target gene recoveries increased the number of acceptable recovery results. Delta-delta tended to bias recoveries fr

  13. Generating relevant kinetic Monte Carlo catalogs using temperature accelerated dynamics with control over the accuracy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chatterjee, Abhijit; Voter, Arthur

    2009-01-01

    We develop a variation of the temperature accelerated dynamics (TAD) method, called the p-TAD method, that efficiently generates an on-the-fly kinetic Monte Carlo (KMC) process catalog with control over the accuracy of the catalog. It is assumed that transition state theory is valid. The p-TAD method guarantees that processes relevant at the timescales of interest to the simulation are present in the catalog with a chosen confidence. A confidence measure associated with the process catalog is derived. The dynamics is then studied using the process catalog with the KMC method. Effective accuracy of a p-TAD calculation is derived when amore » KMC catalog is reused for conditions different from those the catalog was originally generated for. Different KMC catalog generation strategies that exploit the features of the p-TAD method and ensure higher accuracy and/or computational efficiency are presented. The accuracy and the computational requirements of the p-TAD method are assessed. Comparisons to the original TAD method are made. As an example, we study dynamics in sub-monolayer Ag/Cu(110) at the time scale of seconds using the p-TAD method. It is demonstrated that the p-TAD method overcomes several challenges plaguing the conventional KMC method.« less

  14. PAT-tools for process control in pharmaceutical film coating applications.

    PubMed

    Knop, Klaus; Kleinebudde, Peter

    2013-12-05

    Recent development of analytical techniques to monitor the coating process of pharmaceutical solid dosage forms such as pellets and tablets are described. The progress from off- or at-line measurements to on- or in-line applications is shown for the spectroscopic methods near infrared (NIR) and Raman spectroscopy as well as for terahertz pulsed imaging (TPI) and image analysis. The common goal of all these methods is to control or at least to monitor the coating process and/or to estimate the coating end point through timely measurements. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation.

    PubMed

    Huang, Yong; Tao, Gang

    2014-09-01

    The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

  16. A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Yong, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn; Tao, Gang, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn

    2014-09-01

    The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

  17. Aqueous biphasic extraction process with pH and particle control

    DOEpatents

    Chaiko, David J.; Mensah-Biney, R.

    1995-01-01

    A process for aqueous biphasic extraction of metallic oxides and the like from substances containing silica. Control of media pH enables efficient and effective partition of mixture components. The inventive method may be employed to remove excess silica from kaolin clay.

  18. Verification and Validation of Neural Networks for Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale; Nelson, Stacy; Schumman, Johann; Clancy, Daniel (Technical Monitor)

    2002-01-01

    The Dryden Flight Research Center V&V working group and NASA Ames Research Center Automated Software Engineering (ASE) group collaborated to prepare this report. The purpose is to describe V&V processes and methods for certification of neural networks for aerospace applications, particularly adaptive flight control systems like Intelligent Flight Control Systems (IFCS) that use neural networks. This report is divided into the following two sections: 1) Overview of Adaptive Systems; and 2) V&V Processes/Methods.

  19. Verification and Validation of Neural Networks for Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale; Nelson, Stacy; Schumann, Johann

    2002-01-01

    The Dryden Flight Research Center V&V working group and NASA Ames Research Center Automated Software Engineering (ASE) group collaborated to prepare this report. The purpose is to describe V&V processes and methods for certification of neural networks for aerospace applications, particularly adaptive flight control systems like Intelligent Flight Control Systems (IFCS) that use neural networks. This report is divided into the following two sections: Overview of Adaptive Systems and V&V Processes/Methods.

  20. A neuro-data envelopment analysis approach for optimization of uncorrelated multiple response problems with smaller the better type controllable factors

    NASA Astrophysics Data System (ADS)

    Bashiri, Mahdi; Farshbaf-Geranmayeh, Amir; Mogouie, Hamed

    2013-11-01

    In this paper, a new method is proposed to optimize a multi-response optimization problem based on the Taguchi method for the processes where controllable factors are the smaller-the-better (STB)-type variables and the analyzer desires to find an optimal solution with smaller amount of controllable factors. In such processes, the overall output quality of the product should be maximized while the usage of the process inputs, the controllable factors, should be minimized. Since all possible combinations of factors' levels, are not considered in the Taguchi method, the response values of the possible unpracticed treatments are estimated using the artificial neural network (ANN). The neural network is tuned by the central composite design (CCD) and the genetic algorithm (GA). Then data envelopment analysis (DEA) is applied for determining the efficiency of each treatment. Although the important issue for implementation of DEA is its philosophy, which is maximization of outputs versus minimization of inputs, this important issue has been neglected in previous similar studies in multi-response problems. Finally, the most efficient treatment is determined using the maximin weight model approach. The performance of the proposed method is verified in a plastic molding process. Moreover a sensitivity analysis has been done by an efficiency estimator neural network. The results show efficiency of the proposed approach.

  1. Oil content Monitor/Control system and method

    NASA Astrophysics Data System (ADS)

    Schmitt, R. F.; Gavin, J. A.; Kempel, F. D.; Waltrick, C. N.

    1985-07-01

    This patent application discloses an oil content monitor/control unit system which is configured to automatically monitor and control processed effluent from an associated oil/water separator so that if the processed effluent exceeds predetermined in-port or at-sea oil concentration limits, it is either recirculated to an associated oil/water separator via a ship's bilge for additional processing, or diverted to a holding tank for storage. On the other hand, if the oil concentration of the processed effluent is less than determined in-port or at-sea limits, it is discharged overboard.

  2. Fuzzy Adaptive Control for Intelligent Autonomous Space Exploration Problems

    NASA Technical Reports Server (NTRS)

    Esogbue, Augustine O.

    1998-01-01

    The principal objective of the research reported here is the re-design, analysis and optimization of our newly developed neural network fuzzy adaptive controller model for complex processes capable of learning fuzzy control rules using process data and improving its control through on-line adaption. The learned improvement is according to a performance objective function that provides evaluative feedback; this performance objective is broadly defined to meet long-range goals over time. Although fuzzy control had proven effective for complex, nonlinear, imprecisely-defined processes for which standard models and controls are either inefficient, impractical or cannot be derived, the state of the art prior to our work showed that procedures for deriving fuzzy control, however, were mostly ad hoc heuristics. The learning ability of neural networks was exploited to systematically derive fuzzy control and permit on-line adaption and in the process optimize control. The operation of neural networks integrates very naturally with fuzzy logic. The neural networks which were designed and tested using simulation software and simulated data, followed by realistic industrial data were reconfigured for application on several platforms as well as for the employment of improved algorithms. The statistical procedures of the learning process were investigated and evaluated with standard statistical procedures (such as ANOVA, graphical analysis of residuals, etc.). The computational advantage of dynamic programming-like methods of optimal control was used to permit on-line fuzzy adaptive control. Tests for the consistency, completeness and interaction of the control rules were applied. Comparisons to other methods and controllers were made so as to identify the major advantages of the resulting controller model. Several specific modifications and extensions were made to the original controller. Additional modifications and explorations have been proposed for further study. Some of these are in progress in our laboratory while others await additional support. All of these enhancements will improve the attractiveness of the controller as an effective tool for the on line control of an array of complex process environments.

  3. Control method for high-pressure hydrogen vehicle fueling station dispensers

    DOEpatents

    Kountz, Kenneth John; Kriha, Kenneth Robert; Liss, William E.

    2006-06-13

    A method for quick filling a vehicle hydrogen storage vessel with hydrogen, the key component of which is an algorithm used to control the fill process, which interacts with the hydrogen dispensing apparatus to determine the vehicle hydrogen storage vessel capacity.

  4. Manufacturing Research: Self-Directed Control

    DTIC Science & Technology

    1991-01-01

    reduce this sensitivity. SDO is performing Taguchi’s parameter design . 1-13 Statistical Process Control SPC techniques will be used to monitor the process...Florida,R.E. Krieger Pub. Co., 1988. Dehnad, Khowrow, Quality Control . Robust Design . and the Taguchi Method, Pacific Grove, California, Wadsworth... control system. This turns out to be a non -trivial exercise. A human operator can see an event occur (such as the vessel pressurizing above its setpoint

  5. Spacecraft methods and structures with enhanced attitude control that facilitates gyroscope substitutions

    NASA Technical Reports Server (NTRS)

    Li, Rongsheng (Inventor); Kurland, Jeffrey A. (Inventor); Dawson, Alec M. (Inventor); Wu, Yeong-Wei A. (Inventor); Uetrecht, David S. (Inventor)

    2004-01-01

    Methods and structures are provided that enhance attitude control during gyroscope substitutions by insuring that a spacecraft's attitude control system does not drive its absolute-attitude sensors out of their capture ranges. In a method embodiment, an operational process-noise covariance Q of a Kalman filter is temporarily replaced with a substantially greater interim process-noise covariance Q. This replacement increases the weight given to the most recent attitude measurements and hastens the reduction of attitude errors and gyroscope bias errors. The error effect of the substituted gyroscopes is reduced and the absolute-attitude sensors are not driven out of their capture range. In another method embodiment, this replacement is preceded by the temporary replacement of an operational measurement-noise variance R with a substantially larger interim measurement-noise variance R to reduce transients during the gyroscope substitutions.

  6. Monitoring of Lactic Fermentation Process by Ultrasonic Technique

    NASA Astrophysics Data System (ADS)

    Alouache, B.; Touat, A.; Boutkedjirt, T.; Bennamane, A.

    The non-destructive control by using ultrasound techniques has become of great importance in food industry. In this work, Ultrasound has been used for quality control and monitoring the fermentation stages of yogurt, which is a highly consumed product. On the contrary to the physico-chemical methods, where the measurement instruments are directly introduced in the sample, ultrasound techniques have the advantage of being non-destructive and contactless, thus reducing the risk of contamination. Results obtained in this study by using ultrasound seem to be in good agreement with those obtained by physico-chemical methods such as acidity measurement by using a PH-meter instrument. This lets us to conclude that ultrasound method may be an alternative for a healthy control of yoghurt fermentation process.

  7. Manufacturing Methods and Technology Program Automatic In-Process Microcircuit Evaluation.

    DTIC Science & Technology

    1980-10-01

    methods of controlling the AIME system are with the computer and associated inter- face (CPU control), and with controls located on the front panels...Sync and Blanking signals When the AIME system is being operated by the front panel controls , the computer does not influence the system operation. SU...the color video monitor display. The operator controls these parameters by 1) depressing the appropriate key on the keyboard, 2) observing on the

  8. A Quadrupole Dalton-based multi-attribute method for product characterization, process development, and quality control of therapeutic proteins.

    PubMed

    Xu, Weichen; Jimenez, Rod Brian; Mowery, Rachel; Luo, Haibin; Cao, Mingyan; Agarwal, Nitin; Ramos, Irina; Wang, Xiangyang; Wang, Jihong

    2017-10-01

    During manufacturing and storage process, therapeutic proteins are subject to various post-translational modifications (PTMs), such as isomerization, deamidation, oxidation, disulfide bond modifications and glycosylation. Certain PTMs may affect bioactivity, stability or pharmacokinetics and pharmacodynamics profile and are therefore classified as potential critical quality attributes (pCQAs). Identifying, monitoring and controlling these PTMs are usually key elements of the Quality by Design (QbD) approach. Traditionally, multiple analytical methods are utilized for these purposes, which is time consuming and costly. In recent years, multi-attribute monitoring methods have been developed in the biopharmaceutical industry. However, these methods combine high-end mass spectrometry with complicated data analysis software, which could pose difficulty when implementing in a quality control (QC) environment. Here we report a multi-attribute method (MAM) using a Quadrupole Dalton (QDa) mass detector to selectively monitor and quantitate PTMs in a therapeutic monoclonal antibody. The result output from the QDa-based MAM is straightforward and automatic. Evaluation results indicate this method provides comparable results to the traditional assays. To ensure future application in the QC environment, this method was qualified according to the International Conference on Harmonization (ICH) guideline and applied in the characterization of drug substance and stability samples. The QDa-based MAM is shown to be an extremely useful tool for product and process characterization studies that facilitates facile understanding of process impact on multiple quality attributes, while being QC friendly and cost-effective.

  9. Gas turbine engine control system

    NASA Technical Reports Server (NTRS)

    Idelchik, Michael S. (Inventor)

    1991-01-01

    A control system and method of controlling a gas turbine engine. The control system receives an error signal and processes the error signal to form a primary fuel control signal. The control system also receives at least one anticipatory demand signal and processes the signal to form an anticipatory fuel control signal. The control system adjusts the value of the anticipatory fuel control signal based on the value of the error signal to form an adjusted anticipatory signal and then the adjusted anticipatory fuel control signal and the primary fuel control signal are combined to form a fuel command signal.

  10. Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

    PubMed

    Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

    2001-01-01

    Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

  11. Field Impact Evaluation Process on Electronic Tabular Display Subsystem (ETABS).

    DTIC Science & Technology

    1979-10-01

    structural and process techniques are described. These include a diagonal slice approach to team formulation and several different methods of team building, process control and conflict management . (Author)

  12. Modeling, simulation and control of pulsed DE-GMA welding process for joining of aluminum to steel

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Shi, Yu; Li, Jie; Huang, Jiankang; Fan, Ding

    2014-09-01

    Joining of aluminum to steel has attracted significant attention from the welding research community, automotive and rail transportation industries. Many current welding methods have been developed and applied, however, they can not precisely control the heat input to work-piece, they are high costs, low efficiency and consist lots of complex welding devices, and the generated intermetallic compound layer in weld bead interface is thicker. A novel pulsed double electrode gas metal arc welding(Pulsed DE-GMAW) method is developed. To achieve a stable welding process for joining of aluminum to steel, a mathematical model of coupled arc is established, and a new control scheme that uses the average feedback arc voltage of main loop to adjust the wire feed speed to control coupled arc length is proposed and developed. Then, the impulse control simulation of coupled arc length, wire feed speed and wire extension is conducted to demonstrate the mathematical model and predict the stability of welding process by changing the distance of contact tip to work-piece(CTWD). To prove the proposed PSO based PID control scheme's feasibility, the rapid prototyping experimental system is setup and the bead-on-plate control experiments are conducted to join aluminum to steel. The impulse control simulation shows that the established model can accurately represent the variation of coupled arc length, wire feed speed and the average main arc voltage when the welding process is disturbed, and the developed controller has a faster response and adjustment, only runs about 0.1 s. The captured electric signals show the main arc voltage gradually closes to the supposed arc voltage by adjusting the wire feed speed in 0.8 s. The obtained typical current waveform demonstrates that the main current can be reduced by controlling the bypass current under maintaining a relative large total current. The control experiment proves the accuracy of proposed model and feasibility of new control scheme further. The beautiful and smooth weld beads are also obtained by this method. Pulsed DE-GMAW can thus be considered as an alternative method for low cost, high efficiency joining of aluminum to steel.

  13. Employee empowerment through team building and use of process control methods.

    PubMed

    Willems, S

    1998-02-01

    The article examines the use of statistical process control and performance improvement techniques in employee empowerment. The focus is how these techniques provide employees with information to improve their productivity and become involved in the decision-making process. Findings suggest that at one Mississippi hospital employee improvement has had a positive effect on employee productivity, morale, and quality of work.

  14. Dynamics of the process boom machine working equipment under the real law of the hydraulic distributor electric spool control

    NASA Astrophysics Data System (ADS)

    Tarasov, V. N.; Boyarkina, I. V.

    2017-06-01

    Analytical calculation methods of dynamic processes of the self-propelled boom hydraulic machines working equipment are more preferable in comparison with numerical methods. The analytical research method of dynamic processes of the boom hydraulic machines working equipment by means of differential equations of acceleration and braking of the working equipment is proposed. The real control law of a hydraulic distributor electric spool is considered containing the linear law of the electric spool activation and stepped law of the electric spool deactivation. Dependences of dynamic processes of the working equipment on reduced mass, stiffness of hydraulic power cylinder, viscous drag coefficient, piston acceleration, pressure in hydraulic cylinders, inertia force are obtained. Definite recommendations relative to the reduction of dynamic loads, appearing during the working equipment control are considered as the research result. The nature and rate of parameter variations of the speed and piston acceleration dynamic process depend on the law of the ports opening and closure of the hydraulic distributor electric spool. Dynamic loads in the working equipment are decreased during a smooth linear activation of the hydraulic distributor electric spool.

  15. MFAHP: A novel method on the performance evaluation of the industrial wireless networked control system

    NASA Astrophysics Data System (ADS)

    Wu, Linqin; Xu, Sheng; Jiang, Dezhi

    2015-12-01

    Industrial wireless networked control system has been widely used, and how to evaluate the performance of the wireless network is of great significance. In this paper, considering the shortcoming of the existing performance evaluation methods, a comprehensive performance evaluation method of networks multi-indexes fuzzy analytic hierarchy process (MFAHP) combined with the fuzzy mathematics and the traditional analytic hierarchy process (AHP) is presented. The method can overcome that the performance evaluation is not comprehensive and subjective. Experiments show that the method can reflect the network performance of real condition. It has direct guiding role on protocol selection, network cabling, and node setting, and can meet the requirements of different occasions by modifying the underlying parameters.

  16. Aqueous biphasic extraction process with pH and particle control

    DOEpatents

    Chaiko, D.J.; Mensah-Biney, R.

    1995-05-02

    A process for aqueous biphasic extraction of metallic oxides and the like from substances containing silica. Control of media pH enables efficient and effective partition of mixture components. The inventive method may be employed to remove excess silica from kaolin clay. 2 figs.

  17. 14 CFR 21.143 - Quality control data requirements; prime manufacturer.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., purchased items, and parts and assemblies produced by manufacturers' suppliers including methods used to... special manufacturing processes involved, the means used to control the processes, the final test... procedure for recording review board decisions and disposing of rejected parts; (5) An outline of a system...

  18. Steam Hydrocarbon Cracking and Reforming

    ERIC Educational Resources Information Center

    Golombok, Michael

    2004-01-01

    The interactive methods of steam hydrocarbon reforming and cracking of the oil and chemical industries are scrutinized, with special focus on their resemblance and variations. The two methods are illustrations of equilibrium-controlled and kinetically-controlled processes, the analysis of which involves theories, which overlap and balance each…

  19. Fully Mechanically Controlled Automated Electron Microscopic Tomography

    DOE PAGES

    Liu, Jinxin; Li, Hongchang; Zhang, Lei; ...

    2016-07-11

    Knowledge of three-dimensional (3D) structures of each individual particles of asymmetric and flexible proteins is essential in understanding those proteins' functions; but their structures are difficult to determine. Electron tomography (ET) provides a tool for imaging a single and unique biological object from a series of tilted angles, but it is challenging to image a single protein for three-dimensional (3D) reconstruction due to the imperfect mechanical control capability of the specimen goniometer under both a medium to high magnification (approximately 50,000-160,000×) and an optimized beam coherence condition. Here, we report a fully mechanical control method for automating ET data acquisitionmore » without using beam tilt/shift processes. This method could reduce the accumulation of beam tilt/shift that used to compensate the error from the mechanical control, but downgraded the beam coherence. Our method was developed by minimizing the error of the target object center during the tilting process through a closed-loop proportional-integral (PI) control algorithm. The validations by both negative staining (NS) and cryo-electron microscopy (cryo-EM) suggest that this method has a comparable capability to other ET methods in tracking target proteins while maintaining optimized beam coherence conditions for imaging.« less

  20. The trade-off between morphology and control in the co-optimized design of robots.

    PubMed

    Rosendo, Andre; von Atzigen, Marco; Iida, Fumiya

    2017-01-01

    Conventionally, robot morphologies are developed through simulations and calculations, and different control methods are applied afterwards. Assuming that simulations and predictions are simplified representations of our reality, how sure can roboticists be that the chosen morphology is the most adequate for the possible control choices in the real-world? Here we study the influence of the design parameters in the creation of a robot with a Bayesian morphology-control (MC) co-optimization process. A robot autonomously creates child robots from a set of possible design parameters and uses Bayesian Optimization (BO) to infer the best locomotion behavior from real world experiments. Then, we systematically change from an MC co-optimization to a control-only (C) optimization, which better represents the traditional way that robots are developed, to explore the trade-off between these two methods. We show that although C processes can greatly improve the behavior of poor morphologies, such agents are still outperformed by MC co-optimization results with as few as 25 iterations. Our findings, on one hand, suggest that BO should be used in the design process of robots for both morphological and control parameters to reach optimal performance, and on the other hand, point to the downfall of current design methods in face of new search techniques.

  1. The trade-off between morphology and control in the co-optimized design of robots

    PubMed Central

    Iida, Fumiya

    2017-01-01

    Conventionally, robot morphologies are developed through simulations and calculations, and different control methods are applied afterwards. Assuming that simulations and predictions are simplified representations of our reality, how sure can roboticists be that the chosen morphology is the most adequate for the possible control choices in the real-world? Here we study the influence of the design parameters in the creation of a robot with a Bayesian morphology-control (MC) co-optimization process. A robot autonomously creates child robots from a set of possible design parameters and uses Bayesian Optimization (BO) to infer the best locomotion behavior from real world experiments. Then, we systematically change from an MC co-optimization to a control-only (C) optimization, which better represents the traditional way that robots are developed, to explore the trade-off between these two methods. We show that although C processes can greatly improve the behavior of poor morphologies, such agents are still outperformed by MC co-optimization results with as few as 25 iterations. Our findings, on one hand, suggest that BO should be used in the design process of robots for both morphological and control parameters to reach optimal performance, and on the other hand, point to the downfall of current design methods in face of new search techniques. PMID:29023482

  2. Quantitative measurement of intact alpha-synuclein proteoforms from post-mortem control and Parkinson's disease brain tissue by intact protein mass spectrometry.

    PubMed

    Kellie, John F; Higgs, Richard E; Ryder, John W; Major, Anthony; Beach, Thomas G; Adler, Charles H; Merchant, Kalpana; Knierman, Michael D

    2014-07-23

    A robust top down proteomics method is presented for profiling alpha-synuclein species from autopsied human frontal cortex brain tissue from Parkinson's cases and controls. The method was used to test the hypothesis that pathology associated brain tissue will have a different profile of post-translationally modified alpha-synuclein than the control samples. Validation of the sample processing steps, mass spectrometry based measurements, and data processing steps were performed. The intact protein quantitation method features extraction and integration of m/z data from each charge state of a detected alpha-synuclein species and fitting of the data to a simple linear model which accounts for concentration and charge state variability. The quantitation method was validated with serial dilutions of intact protein standards. Using the method on the human brain samples, several previously unreported modifications in alpha-synuclein were identified. Low levels of phosphorylated alpha synuclein were detected in brain tissue fractions enriched for Lewy body pathology and were marginally significant between PD cases and controls (p = 0.03).

  3. Controlling Force and Depth in Friction Stir Welding

    NASA Technical Reports Server (NTRS)

    Adams, Glynn; Loftus, Zachary; McCormac, Nathan; Venable, Richard

    2005-01-01

    Feedback control of the penetration force applied to a pin tool in friction stir welding has been found to be a robust and reliable means for controlling the depth of penetration of the tool. This discovery has made it possible to simplify depth control and to weld with greater repeatability, even on workpieces with long weld joints. Prior to this discovery, depths of penetration in friction stir welding were controlled by hard-tooled roller assemblies or by depth actuators controlled by feedback from such external sensors as linear variable-differential transformers or laser-based devices. These means of control are limited: A hard-tooled roller assembly confines a pin tool to a preset depth that cannot be changed easily during the welding process. A measurement by an external sensor is only an indirect indicative of the depth of penetration, and computations to correlate such a measurement with a depth of penetration are vulnerable to error. The present force-feedback approach exploits the proportionality between the depth and the force of penetration Unlike a depth measurement taken by an external sensor, a force measurement can be direct because it can be taken by a sensor coupled directly to the pin tool. The reading can be processed through a modern electronic servo control system to control an actuator to keep the applied penetration force at the desired level. In comparison with the older depth-control methods described above, this method offers greater sensitivity to plasticizing of the workpiece metal and is less sensitive to process noise, resulting in a more consistent process. In an experiment, a tapered panel was friction stir welded while controlling the force of penetration according to this method. The figure is a plot of measurements taken during the experiment, showing that force was controlled with a variation of 200 lb (890 N), resulting in control of the depth of penetration with a variation of 0.004 in. (0.1 mm).

  4. Expert system and process optimization techniques for real-time monitoring and control of plasma processes

    NASA Astrophysics Data System (ADS)

    Cheng, Jie; Qian, Zhaogang; Irani, Keki B.; Etemad, Hossein; Elta, Michael E.

    1991-03-01

    To meet the ever-increasing demand of the rapidly-growing semiconductor manufacturing industry it is critical to have a comprehensive methodology integrating techniques for process optimization real-time monitoring and adaptive process control. To this end we have accomplished an integrated knowledge-based approach combining latest expert system technology machine learning method and traditional statistical process control (SPC) techniques. This knowledge-based approach is advantageous in that it makes it possible for the task of process optimization and adaptive control to be performed consistently and predictably. Furthermore this approach can be used to construct high-level and qualitative description of processes and thus make the process behavior easy to monitor predict and control. Two software packages RIST (Rule Induction and Statistical Testing) and KARSM (Knowledge Acquisition from Response Surface Methodology) have been developed and incorporated with two commercially available packages G2 (real-time expert system) and ULTRAMAX (a tool for sequential process optimization).

  5. Methods of measurement for semiconductor materials, process control, and devices

    NASA Technical Reports Server (NTRS)

    Bullis, W. M. (Editor)

    1972-01-01

    Activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices are described. Topics investigated include: measurements of transistor delay time; application of the infrared response technique to the study of radiation-damaged, lithium-drifted silicon detectors; and identification of a condition that minimizes wire flexure and reduces the failure rate of wire bonds in transistors and integrated circuits under slow thermal cycling conditions. Supplementary data concerning staff, standards committee activities, technical services, and publications are included as appendixes.

  6. Method for controlling gas metal arc welding

    DOEpatents

    Smartt, Herschel B.; Einerson, Carolyn J.; Watkins, Arthur D.

    1989-01-01

    The heat input and mass input in a Gas Metal Arc welding process are controlled by a method that comprises calculating appropriate values for weld speed, filler wire feed rate and an expected value for the welding current by algorithmic function means, applying such values for weld speed and filler wire feed rate to the welding process, measuring the welding current, comparing the measured current to the calculated current, using said comparison to calculate corrections for the weld speed and filler wire feed rate, and applying corrections.

  7. Methods of measurement for semiconductor materials, process control, and devices

    NASA Technical Reports Server (NTRS)

    Bullis, W. M. (Editor)

    1971-01-01

    The development of methods of measurement for semiconductor materials, process control, and devices is discussed. The following subjects are also presented: (1) demonstration of the high sensitivity of the infrared response technique by the identification of gold in a germanium diode, (2) verification that transient thermal response is significantly more sensitive to the presence of voids in die attachment than steady-state thermal resistance, and (3) development of equipment for determining susceptibility of transistors to hot spot formation by the current-gain technique.

  8. Rapid thermal processing by stamping

    DOEpatents

    Stradins, Pauls; Wang, Qi

    2013-03-05

    A rapid thermal processing device and methods are provided for thermal processing of samples such as semiconductor wafers. The device has components including a stamp (35) having a stamping surface and a heater or cooler (40) to bring it to a selected processing temperature, a sample holder (20) for holding a sample (10) in position for intimate contact with the stamping surface; and positioning components (25) for moving the stamping surface and the stamp (35) in and away from intimate, substantially non-pressured contact. Methods for using and making such devices are also provided. These devices and methods allow inexpensive, efficient, easily controllable thermal processing.

  9. Preliminary Retrospective Analysis of Daily Tomotherapy Output Constancy Checks Using Statistical Process Control.

    PubMed

    Mezzenga, Emilio; D'Errico, Vincenzo; Sarnelli, Anna; Strigari, Lidia; Menghi, Enrico; Marcocci, Francesco; Bianchini, David; Benassi, Marcello

    2016-01-01

    The purpose of this study was to retrospectively evaluate the results from a Helical TomoTherapy Hi-Art treatment system relating to quality controls based on daily static and dynamic output checks using statistical process control methods. Individual value X-charts, exponentially weighted moving average charts, and process capability and acceptability indices were used to monitor the treatment system performance. Daily output values measured from January 2014 to January 2015 were considered. The results obtained showed that, although the process was in control, there was an out-of-control situation in the principal maintenance intervention for the treatment system. In particular, process capability indices showed a decreasing percentage of points in control which was, however, acceptable according to AAPM TG148 guidelines. Our findings underline the importance of restricting the acceptable range of daily output checks and suggest a future line of investigation for a detailed process control of daily output checks for the Helical TomoTherapy Hi-Art treatment system.

  10. Prevention of Salmonella cross-contamination in an oilmeal manufacturing plant.

    PubMed

    Morita, T; Kitazawa, H; Iida, T; Kamata, S

    2006-08-01

    The mechanisms of Salmonella contamination in an oilmeal plant were investigated and the basic data were collected in order to achieve control of Salmonella in oilmeal. Salmonella was detected in all contamination vectors and environmental factors investigated, namely: operators, processing floor, dust in the air and rodents. In particular, high concentrations of Salmonella were detected on the processing floor of the manufacturing area, which has high oil content. Steam was the most effective disinfection method used for the processing floor, as the effects of heat sterilization and disinfection may work in tandem. In addition, restricting the movement of operators of the production chain remarkably reduced Salmonella contamination, even in areas of otherwise high contamination. Within the oilmeal plant, high Salmonella contamination rates for the processing floor represent the greatest risk of contamination of oilmeal via operators, dust in the air and rodents. Therefore, control of the processing floor is the most important means for reducing the oilmeal contamination rate. Specific Salmonella control methods for oilmeal plants have been established.

  11. Enhanced High Performance Power Compensation Methodology by IPFC Using PIGBT-IDVR

    PubMed Central

    Arumugom, Subramanian; Rajaram, Marimuthu

    2015-01-01

    Currently, power systems are involuntarily controlled without high speed control and are frequently initiated, therefore resulting in a slow process when compared with static electronic devices. Among various power interruptions in power supply systems, voltage dips play a central role in causing disruption. The dynamic voltage restorer (DVR) is a process based on voltage control that compensates for line transients in the distributed system. To overcome these issues and to achieve a higher speed, a new methodology called the Parallel IGBT-Based Interline Dynamic Voltage Restorer (PIGBT-IDVR) method has been proposed, which mainly spotlights the dynamic processing of energy reloads in common dc-linked energy storage with less adaptive transition. The interline power flow controller (IPFC) scheme has been employed to manage the power transmission between the lines and the restorer method for controlling the reactive power in the individual lines. By employing the proposed methodology, the failure of a distributed system has been avoided and provides better performance than the existing methodologies. PMID:26613101

  12. A kinetic Monte Carlo simulation method of van der Waals epitaxy for atomistic nucleation-growth processes of transition metal dichalcogenides.

    PubMed

    Nie, Yifan; Liang, Chaoping; Cha, Pil-Ryung; Colombo, Luigi; Wallace, Robert M; Cho, Kyeongjae

    2017-06-07

    Controlled growth of crystalline solids is critical for device applications, and atomistic modeling methods have been developed for bulk crystalline solids. Kinetic Monte Carlo (KMC) simulation method provides detailed atomic scale processes during a solid growth over realistic time scales, but its application to the growth modeling of van der Waals (vdW) heterostructures has not yet been developed. Specifically, the growth of single-layered transition metal dichalcogenides (TMDs) is currently facing tremendous challenges, and a detailed understanding based on KMC simulations would provide critical guidance to enable controlled growth of vdW heterostructures. In this work, a KMC simulation method is developed for the growth modeling on the vdW epitaxy of TMDs. The KMC method has introduced full material parameters for TMDs in bottom-up synthesis: metal and chalcogen adsorption/desorption/diffusion on substrate and grown TMD surface, TMD stacking sequence, chalcogen/metal ratio, flake edge diffusion and vacancy diffusion. The KMC processes result in multiple kinetic behaviors associated with various growth behaviors observed in experiments. Different phenomena observed during vdW epitaxy process are analysed in terms of complex competitions among multiple kinetic processes. The KMC method is used in the investigation and prediction of growth mechanisms, which provide qualitative suggestions to guide experimental study.

  13. Centralized PI control for high dimensional multivariable systems based on equivalent transfer function.

    PubMed

    Luan, Xiaoli; Chen, Qiang; Liu, Fei

    2014-09-01

    This article presents a new scheme to design full matrix controller for high dimensional multivariable processes based on equivalent transfer function (ETF). Differing from existing ETF method, the proposed ETF is derived directly by exploiting the relationship between the equivalent closed-loop transfer function and the inverse of open-loop transfer function. Based on the obtained ETF, the full matrix controller is designed utilizing the existing PI tuning rules. The new proposed ETF model can more accurately represent the original processes. Furthermore, the full matrix centralized controller design method proposed in this paper is applicable to high dimensional multivariable systems with satisfactory performance. Comparison with other multivariable controllers shows that the designed ETF based controller is superior with respect to design-complexity and obtained performance. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  14. Methods of Measurement for Semiconductor Materials, Process Control, and Devices

    NASA Technical Reports Server (NTRS)

    Bullis, W. M. (Editor)

    1973-01-01

    The development of methods of measurement for semiconductor materials, process control, and devices is reported. Significant accomplishments include: (1) Completion of an initial identification of the more important problems in process control for integrated circuit fabrication and assembly; (2) preparations for making silicon bulk resistivity wafer standards available to the industry; and (3) establishment of the relationship between carrier mobility and impurity density in silicon. Work is continuing on measurement of resistivity of semiconductor crystals; characterization of generation-recombination-trapping centers, including gold, in silicon; evaluation of wire bonds and die attachment; study of scanning electron microscopy for wafer inspection and test; measurement of thermal properties of semiconductor devices; determination of S-parameters and delay time in junction devices; and characterization of noise and conversion loss of microwave detector diodes.

  15. Mesoporous metal oxides and processes for preparation thereof

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suib, Steven L.; Poyraz, Altug Suleyman

    A process for preparing a mesoporous metal oxide, i.e., transition metal oxide. Lanthanide metal oxide, a post-transition metal oxide and metalloid oxide. The process comprises providing an acidic mixture comprising a metal precursor, an interface modifier, a hydrotropic ion precursor, and a surfactant; and heating the acidic mixture at a temperature and for a period of time sufficient to form the mesoporous metal oxide. A mesoporous metal oxide prepared by the above process. A method of controlling nano-sized wall crystallinity and mesoporosity in mesoporous metal oxides. The method comprises providing an acidic mixture comprising a metal precursor, an interface modifier,more » a hydrotropic ion precursor, and a surfactant; and heating the acidic mixture at a temperature and for a period of time sufficient to control nano-sized wall crystallinity and mesoporosity in the mesoporous metal oxides. Mesoporous metal oxides and a method of tuning structural properties of mesoporous metal oxides.« less

  16. Research on single-chip microcomputer controlled rotating magnetic field mineralization model

    NASA Astrophysics Data System (ADS)

    Li, Yang; Qi, Yulin; Yang, Junxiao; Li, Na

    2017-08-01

    As one of the method of selecting ore, the magnetic separation method has the advantages of stable operation, simple process flow, high beneficiation efficiency and no chemical environment pollution. But the existing magnetic separator are more mechanical, the operation is not flexible, and can not change the magnetic field parameters according to the precision of the ore needed. Based on the existing magnetic separator is mechanical, the rotating magnetic field can be used for single chip microcomputer control as the research object, design and trial a rotating magnetic field processing prototype, and through the single-chip PWM pulse output to control the rotation of the magnetic field strength and rotating magnetic field speed. This method of using pure software to generate PWM pulse to control rotary magnetic field beneficiation, with higher flexibility, accuracy and lower cost, can give full play to the performance of single-chip.

  17. Observation of negative differential resistance in mesoscopic graphene oxide devices.

    PubMed

    Rathi, Servin; Lee, Inyeal; Kang, Moonshik; Lim, Dongsuk; Lee, Yoontae; Yamacli, Serhan; Joh, Han-Ik; Kim, Seongsu; Kim, Sang-Woo; Yun, Sun Jin; Choi, Sukwon; Kim, Gil-Ho

    2018-05-08

    The fractions of various functional groups in graphene oxide (GO) are directly related to its electrical and chemical properties and can be controlled by various reduction methods like thermal, chemical and optical. However, a method with sufficient controllability to regulate the reduction process has been missing. In this work, a hybrid method of thermal and joule heating processes is demonstrated where a progressive control of the ratio of various functional groups can be achieved in a localized area. With this precise control of carbon-oxygen ratio, negative differential resistance (NDR) is observed in the current-voltage characteristics of a two-terminal device in the ambient environment due to charge-activated electrochemical reactions at the GO surface. This experimental observation correlates with the optical and chemical characterizations. This NDR behavior offers new opportunities for the fabrication and application of such novel electronic devices in a wide range of devices applications including switches and oscillators.

  18. Hands-On Hydroponics

    ERIC Educational Resources Information Center

    Carver, Jeffrey; Wasserman, Bradley

    2012-01-01

    Hydroponics is a process in which plants are grown using nutrient-rich water instead of soil. Because this process maximizes the use of water and nutrients--providing only what the plant uses in controlled and easily maintained systems--it is a viable alternative to traditional farming methods. The amount of control in these systems also ensures…

  19. Process for guidance, containment, treatment, and imaging in a subsurface environment utilizing ferro-fluids

    DOEpatents

    Moridis, George J.; Oldenburg, Curtis M.

    2001-01-01

    Disclosed are processes for monitoring and control of underground contamination, which involve the application of ferrofluids. Two broad uses of ferrofluids are described: (1) to control liquid movement by the application of strong external magnetic fields; and (2) to image liquids by standard geophysical methods.

  20. A Numerical Process Control Method for Circular-Tube Hydroforming Prediction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, Kenneth I.; Nguyen, Ba Nghiep; Davies, Richard W.

    2004-03-01

    This paper describes the development of a solution control method that tracks the stresses, strains and mechanical behavior of a tube during hydroforming to estimate the proper axial feed (end-feed) and internal pressure loads through time. The analysis uses the deformation theory of plasticity and Hill?s criterion to describe the plastic flow. Before yielding, the pressure and end-feed increments are estimated based on the initial tube geometry, elastic properties and yield stress. After yielding, the pressure increment is calculated based on the tube geometry at the previous solution increment and the current hoop stress increment. The end-feed increment is computedmore » from the increment of the axial plastic strain. Limiting conditions such as column buckling (of long tubes), local axi-symmetric wrinkling of shorter tubes, and bursting due to localized wall thinning are considered. The process control method has been implemented in the Marc finite element code. Hydroforming simulations using this process control method were conducted to predict the load histories for controlled expansion of 6061-T4 aluminum tubes within a conical die shape and under free hydroforming conditions. The predicted loading paths were transferred to the hydroforming equipment to form the conical and free-formed tube shapes. The model predictions and experimental results are compared for deformed shape, strains and the extent of forming at rupture.« less

  1. A real time, FEM based optimal control algorithm and its implementation using parallel processing hardware (transistors) in a microprocessor environment

    NASA Technical Reports Server (NTRS)

    Patten, William Neff

    1989-01-01

    There is an evident need to discover a means of establishing reliable, implementable controls for systems that are plagued by nonlinear and, or uncertain, model dynamics. The development of a generic controller design tool for tough-to-control systems is reported. The method utilizes a moving grid, time infinite element based solution of the necessary conditions that describe an optimal controller for a system. The technique produces a discrete feedback controller. Real time laboratory experiments are now being conducted to demonstrate the viability of the method. The algorithm that results is being implemented in a microprocessor environment. Critical computational tasks are accomplished using a low cost, on-board, multiprocessor (INMOS T800 Transputers) and parallel processing. Progress to date validates the methodology presented. Applications of the technique to the control of highly flexible robotic appendages are suggested.

  2. Metal Catalyst for Low-Temperature Growth of Controlled Zinc Oxide Nanowires on Arbitrary Substrates

    PubMed Central

    Kim, Baek Hyun; Kwon, Jae W.

    2014-01-01

    Zinc oxide nanowires generated by hydrothermal method present superior physical and chemical characteristics. Quality control of the growth has been very challenging and controlled growth is only achievable under very limited conditions using homogeneous seed layers with high temperature processes. Here we show the controlled ZnO nanowire growth on various organic and inorganic materials without the requirement of a homogeneous seed layer and a high temperature process. We also report the discovery of an important role of the electronegativity in the nanowire growth on arbitrary substrates. Using heterogeneous metal oxide interlayers with low-temperature hydrothermal methods, we demonstrate well-controlled ZnO nanowire arrays and single nanowires on flat or curved surfaces. A metal catalyst and heterogeneous metal oxide interlayers are found to determine lattice-match with ZnO and to largely influence the controlled alignment. These findings will contribute to the development of novel nanodevices using controlled nanowires. PMID:24625584

  3. Method for measuring and controlling beam current in ion beam processing

    DOEpatents

    Kearney, Patrick A.; Burkhart, Scott C.

    2003-04-29

    A method for producing film thickness control of ion beam sputter deposition films. Great improvements in film thickness control is accomplished by keeping the total current supplied to both the beam and suppressor grids of a radio frequency (RF) in beam source constant, rather than just the current supplied to the beam grid. By controlling both currents, using this method, deposition rates are more stable, and this allows the deposition of layers with extremely well controlled thicknesses to about 0.1%. The method is carried out by calculating deposition rates based on the total of the suppressor and beam currents and maintaining the total current constant by adjusting RF power which gives more consistent values.

  4. Using Statistical Process Control to Drive Improvement in Neonatal Care: A Practical Introduction to Control Charts.

    PubMed

    Gupta, Munish; Kaplan, Heather C

    2017-09-01

    Quality improvement (QI) is based on measuring performance over time, and variation in data measured over time must be understood to guide change and make optimal improvements. Common cause variation is natural variation owing to factors inherent to any process; special cause variation is unnatural variation owing to external factors. Statistical process control methods, and particularly control charts, are robust tools for understanding data over time and identifying common and special cause variation. This review provides a practical introduction to the use of control charts in health care QI, with a focus on neonatology. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Multi-allergen Quantitation and the Impact of Thermal Treatment in Industry-Processed Baked Goods by ELISA and Liquid Chromatography-Tandem Mass Spectrometry.

    PubMed

    Parker, Christine H; Khuda, Sefat E; Pereira, Marion; Ross, Mark M; Fu, Tong-Jen; Fan, Xuebin; Wu, Yan; Williams, Kristina M; DeVries, Jonathan; Pulvermacher, Brian; Bedford, Binaifer; Zhang, Xi; Jackson, Lauren S

    2015-12-16

    Undeclared food allergens account for 30-40% of food recalls in the United States. Compliance with ingredient labeling regulations and the implementation of effective manufacturing allergen control plans require the use of reliable methods for allergen detection and quantitation in complex food products. The objectives of this work were to (1) produce industry-processed model foods incurred with egg, milk, and peanut allergens, (2) compare analytical method performance for allergen quantitation in thermally processed bakery products, and (3) determine the effects of thermal treatment on allergen detection. Control and allergen-incurred cereal bars and muffins were formulated in a pilot-scale industry processing facility. Quantitation of egg, milk, and peanut in incurred baked goods was compared at various processing stages using commercial enzyme-linked immunosorbent assay (ELISA) kits and a novel multi-allergen liquid chromatography (LC)-tandem mass spectrometry (MS/MS) multiple-reaction monitoring (MRM) method. Thermal processing was determined to negatively affect the recovery and quantitation of egg, milk, and peanut to different extents depending on the allergen, matrix, and analytical test method. The Morinaga ELISA and LC-MS/MS quantitative methods reported the highest recovery across all monitored allergens, whereas the ELISA Systems, Neogen BioKits, Neogen Veratox, and R-Biopharm ELISA Kits underperformed in the determination of allergen content of industry-processed bakery products.

  6. Improved compliance by BPM-driven workflow automation.

    PubMed

    Holzmüller-Laue, Silke; Göde, Bernd; Fleischer, Heidi; Thurow, Kerstin

    2014-12-01

    Using methods and technologies of business process management (BPM) for the laboratory automation has important benefits (i.e., the agility of high-level automation processes, rapid interdisciplinary prototyping and implementation of laboratory tasks and procedures, and efficient real-time process documentation). A principal goal of the model-driven development is the improved transparency of processes and the alignment of process diagrams and technical code. First experiences of using the business process model and notation (BPMN) show that easy-to-read graphical process models can achieve and provide standardization of laboratory workflows. The model-based development allows one to change processes quickly and an easy adaption to changing requirements. The process models are able to host work procedures and their scheduling in compliance with predefined guidelines and policies. Finally, the process-controlled documentation of complex workflow results addresses modern laboratory needs of quality assurance. BPMN 2.0 as an automation language to control every kind of activity or subprocess is directed to complete workflows in end-to-end relationships. BPMN is applicable as a system-independent and cross-disciplinary graphical language to document all methods in laboratories (i.e., screening procedures or analytical processes). That means, with the BPM standard, a communication method of sharing process knowledge of laboratories is also available. © 2014 Society for Laboratory Automation and Screening.

  7. Social Information Processing of Positive and Negative Hypothetical Events in Children with ADHD and Conduct Problems and Controls

    ERIC Educational Resources Information Center

    Andrade, Brendan F.; Waschbusch, Daniel A.; Doucet, Amelie; King, Sara; MacKinnon, Maura; McGrath, Patrick J.; Stewart, Sherry H.; Corkum, Penny

    2012-01-01

    Objective: This study examined social information processing (SIP) of events with varied outcomes in children with ADHD and conduct problems (CPs; defined as oppositional defiant disorder [ODD] or conduct disorder [CD]) and controls. Method: Participants were 64 children (46 boys, 18 girls) aged 6 to 12, including 39 with ADHD and 25 controls.…

  8. Analysis and quality control of carbohydrates in therapeutic proteins with fluorescence HPLC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Kun; Huang, Jian; Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 610054

    Conbercept is an Fc fusion protein with very complicated carbohydrate profiles which must be carefully monitored through manufacturing process. Here, we introduce an optimized fluorescence derivatization high-performance liquid chromatographic method for glycan mapping in conbercept. Compared with conventional glycan analysis method, this method has much better resolution and higher reproducibility making it excellent for product quality control.

  9. Maximum likelihood identification and optimal input design for identifying aircraft stability and control derivatives

    NASA Technical Reports Server (NTRS)

    Stepner, D. E.; Mehra, R. K.

    1973-01-01

    A new method of extracting aircraft stability and control derivatives from flight test data is developed based on the maximum likelihood cirterion. It is shown that this new method is capable of processing data from both linear and nonlinear models, both with and without process noise and includes output error and equation error methods as special cases. The first application of this method to flight test data is reported for lateral maneuvers of the HL-10 and M2/F3 lifting bodies, including the extraction of stability and control derivatives in the presence of wind gusts. All the problems encountered in this identification study are discussed. Several different methods (including a priori weighting, parameter fixing and constrained parameter values) for dealing with identifiability and uniqueness problems are introduced and the results given. The method for the design of optimal inputs for identifying the parameters of linear dynamic systems is also given. The criterion used for the optimization is the sensitivity of the system output to the unknown parameters. Several simple examples are first given and then the results of an extensive stability and control dervative identification simulation for a C-8 aircraft are detailed.

  10. Fouling on ion-exchange membranes: Classification, characterization and strategies of prevention and control.

    PubMed

    Mikhaylin, Sergey; Bazinet, Laurent

    2016-03-01

    The environmentally friendly ion-exchange membrane (IEM) processes find more and more applications in the modern industries in order to demineralize, concentrate and modify products. Moreover, these processes may be applied for the energy conversion and storage. However, the main drawback of the IEM processes is a formation of fouling, which significantly decreases the process efficiency and increases the process cost. The present review is dedicated to the problematic of IEM fouling phenomena. Firstly, the major types of IEM fouling such as colloidal fouling, organic fouling, scaling and biofouling are discussed along with consideration of the main factors affecting fouling formation and development. Secondly, the review of the possible methods of IEM fouling characterization is provided. This section includes the methods of fouling visualization and characterization as well as methods allowing investigations of characteristics of the fouled IEMs. Eventually, the reader will find the conventional and modern strategies of prevention and control of different fouling types. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Designing Class Methods from Dataflow Diagrams

    NASA Astrophysics Data System (ADS)

    Shoval, Peretz; Kabeli-Shani, Judith

    A method for designing the class methods of an information system is described. The method is part of FOOM - Functional and Object-Oriented Methodology. In the analysis phase of FOOM, two models defining the users' requirements are created: a conceptual data model - an initial class diagram; and a functional model - hierarchical OO-DFDs (object-oriented dataflow diagrams). Based on these models, a well-defined process of methods design is applied. First, the OO-DFDs are converted into transactions, i.e., system processes that supports user task. The components and the process logic of each transaction are described in detail, using pseudocode. Then, each transaction is decomposed, according to well-defined rules, into class methods of various types: basic methods, application-specific methods and main transaction (control) methods. Each method is attached to a proper class; messages between methods express the process logic of each transaction. The methods are defined using pseudocode or message charts.

  12. Method of Optimizing the Construction of Machining, Assembly and Control Devices

    NASA Astrophysics Data System (ADS)

    Iordache, D. M.; Costea, A.; Niţu, E. L.; Rizea, A. D.; Babă, A.

    2017-10-01

    Industry dynamics, driven by economic and social requirements, must generate more interest in technological optimization, capable of ensuring a steady development of advanced technical means to equip machining processes. For these reasons, the development of tools, devices, work equipment and control, as well as the modernization of machine tools, is the certain solution to modernize production systems that require considerable time and effort. This type of approach is also related to our theoretical, experimental and industrial applications of recent years, presented in this paper, which have as main objectives the elaboration and use of mathematical models, new calculation methods, optimization algorithms, new processing and control methods, as well as some structures for the construction and configuration of technological equipment with a high level of performance and substantially reduced costs..

  13. Optimal Control of the Valve Based on Traveling Wave Method in the Water Hammer Process

    NASA Astrophysics Data System (ADS)

    Cao, H. Z.; Wang, F.; Feng, J. L.; Tan, H. P.

    2011-09-01

    Valve regulation is an effective method for process control during the water hammer. The principle of d'Alembert traveling wave theory was used in this paper to construct the exact analytical solution of the water hammer, and the optimal speed law of the valve that can reduce the water hammer pressure in the maximum extent was obtained. Combining this law with the valve characteristic curve, the principle corresponding to the valve opening changing with time was obtained, which can be used to guide the process of valve closing and to reduce the water hammer pressure in the maximum extent.

  14. Intelligent tuning method of PID parameters based on iterative learning control for atomic force microscopy.

    PubMed

    Liu, Hui; Li, Yingzi; Zhang, Yingxu; Chen, Yifu; Song, Zihang; Wang, Zhenyu; Zhang, Suoxin; Qian, Jianqiang

    2018-01-01

    Proportional-integral-derivative (PID) parameters play a vital role in the imaging process of an atomic force microscope (AFM). Traditional parameter tuning methods require a lot of manpower and it is difficult to set PID parameters in unattended working environments. In this manuscript, an intelligent tuning method of PID parameters based on iterative learning control is proposed to self-adjust PID parameters of the AFM according to the sample topography. This method gets enough information about the output signals of PID controller and tracking error, which will be used to calculate the proper PID parameters, by repeated line scanning until convergence before normal scanning to learn the topography. Subsequently, the appropriate PID parameters are obtained by fitting method and then applied to the normal scanning process. The feasibility of the method is demonstrated by the convergence analysis. Simulations and experimental results indicate that the proposed method can intelligently tune PID parameters of the AFM for imaging different topographies and thus achieve good tracking performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Reducing Bolt Preload Variation with Angle-of-Twist Bolt Loading

    NASA Technical Reports Server (NTRS)

    Thompson, Bryce; Nayate, Pramod; Smith, Doug; McCool, Alex (Technical Monitor)

    2001-01-01

    Critical high-pressure sealing joints on the Space Shuttle reusable solid rocket motor require precise control of bolt preload to ensure proper joint function. As the reusable solid rocket motor experiences rapid internal pressurization, correct bolt preloads maintain the sealing capability and structural integrity of the hardware. The angle-of-twist process provides the right combination of preload accuracy, reliability, process control, and assembly-friendly design. It improves significantly over previous methods. The sophisticated angle-of-twist process controls have yielded answers to all discrepancies encountered while the simplicity of the root process has assured joint preload reliability.

  16. Modeling and Advanced Control for Sustainable Process ...

    EPA Pesticide Factsheets

    This book chapter introduces a novel process systems engineering framework that integrates process control with sustainability assessment tools for the simultaneous evaluation and optimization of process operations. The implemented control strategy consists of a biologically-inspired, multi-agent-based method. The sustainability and performance assessment of process operating points is carried out using the U.S. E.P.A.’s GREENSCOPE assessment tool that provides scores for the selected economic, material management, environmental and energy indicators. The indicator results supply information on whether the implementation of the controller is moving the process towards a more sustainable operation. The effectiveness of the proposed framework is illustrated through a case study of a continuous bioethanol fermentation process whose dynamics are characterized by steady-state multiplicity and oscillatory behavior. This book chapter contribution demonstrates the application of novel process control strategies for sustainability by increasing material management, energy efficiency, and pollution prevention, as needed for SHC Sustainable Uses of Wastes and Materials Management.

  17. Trace Contaminant Control During the International Space Station's On-Orbit Assembly and Outfitting

    NASA Technical Reports Server (NTRS)

    Perry, J. L.

    2017-01-01

    Achieving acceptable cabin air quality must balance competing elements during spacecraft design, assembly, ground processing, and flight operations. Among the elements that contribute to the trace chemical contaminant load and, therefore, the cabin air quality aboard crewed spacecraft are the vehicle configuration, crew size and activities, mission duration and objectives, materials selection, and vehicle manufacturing and preflight ground processing methods. Trace chemical contaminants produced from pervasive sources such as equipment offgassing, human metabolism, and cleaning fluids during preflight ground processing present challenges to maintaining acceptable cabin air quality. To address these challenges, both passive and active contamination control techniques are used during a spacecraft's design, manufacturing, preflight preparation, and operational phases. Passive contamination control methods seek to minimize the equipment offgassing load by selecting materials, manufacturing processes, preflight preparation processes, and in-flight operations that have low chemical offgassing characteristics. Passive methods can be employed across the spacecraft's entire life cycle from conceptual design through flight operations. However, because the passive contamination control techniques cannot fully eliminate the contaminant load, active contamination control equipment must be deployed aboard the spacecraft to purify and revitalize the cabin atmosphere during in-flight operations. Verifying that the passive contamination control techniques have successfully maintained the total trace contaminant load within the active contamination control equipment's capabilities occurs late in the preflight preparation stages. This verification consists of subjecting the spacecraft to an offgassing test to determine the trace contaminant load. This load is then assessed versus the active contamination control equipment's capabilities via trace contaminant control (TCC) engineering analysis. During the International Space Station's (ISS's) on-orbit assembly and outfitting, a series of engineering analyses were conducted to evaluate how effective the passive TCC methods were relative to providing adequate operational margin for the active TCC equipment's capabilities aboard the ISS. These analyses were based on habitable module and cargo vehicle offgassing test results. The offgassing test for a fully assembled module or cargo vehicle is an important preflight spacecraft evaluation method that has been used successfully during all crewed spacecraft programs to provide insight into how effectively the passive contamination control methods limit the equipment offgassing component of the overall trace contaminant generation load. The progression of TCC assessments beginning in 1998 with the ISS's first habitable element launch and continuing through the final pressurized element's arrival in 2010 are presented. Early cargo vehicle flight assessments between 2008 and 2011 are also presented as well as a discussion on predictive methods for assessing cargo via a purely analytical technique. The technical approach for TCC employed during this 13-year period successfully maintained the cabin atmospheric quality within specified parameters during the technically challenging ISS assembly and outfitting stages. The following narrative provides details on the important role of spacecraft offgassing testing, trace contaminant performance requirements, and flight rules for achieving the ultimate result-a cabin environment that enables people to live and work safely in space.

  18. Terrestrial photovoltaic cell process testing

    NASA Technical Reports Server (NTRS)

    Burger, D. R.

    1985-01-01

    The paper examines critical test parameters, criteria for selecting appropriate tests, and the use of statistical controls and test patterns to enhance PV-cell process test results. The coverage of critical test parameters is evaluated by examining available test methods and then screening these methods by considering the ability to measure those critical parameters which are most affected by the generic process, the cost of the test equipment and test performance, and the feasibility for process testing.

  19. Terrestrial photovoltaic cell process testing

    NASA Astrophysics Data System (ADS)

    Burger, D. R.

    The paper examines critical test parameters, criteria for selecting appropriate tests, and the use of statistical controls and test patterns to enhance PV-cell process test results. The coverage of critical test parameters is evaluated by examining available test methods and then screening these methods by considering the ability to measure those critical parameters which are most affected by the generic process, the cost of the test equipment and test performance, and the feasibility for process testing.

  20. New method of control of tooth whitening

    NASA Astrophysics Data System (ADS)

    Angelov, I.; Mantareva, V.; Gisbrecht, A.; Valkanov, S.; Uzunov, Tz.

    2010-10-01

    New methods of control of tooth bleaching stages through simultaneous measurements of a reflected light and a fluorescence signal are proposed. It is shown that the bleaching process leads to significant changes in the intensity of a scattered signal and also in the shape and intensity of the fluorescence spectra. Experimental data illustrate that the bleaching process causes essential changes in the teeth discoloration in short time as 8-10 min from the beginning of the application procedure. The continuation of the treatment is not necessary moreover the probability of the enamel destroy increases considerably. The proposed optical back control of tooth surface is a base for development of a practical set up to control the duration of the bleaching procedure.

  1. Modified Exponential Weighted Moving Average (EWMA) Control Chart on Autocorrelation Data

    NASA Astrophysics Data System (ADS)

    Herdiani, Erna Tri; Fandrilla, Geysa; Sunusi, Nurtiti

    2018-03-01

    In general, observations of the statistical process control are assumed to be mutually independence. However, this assumption is often violated in practice. Consequently, statistical process controls were developed for interrelated processes, including Shewhart, Cumulative Sum (CUSUM), and exponentially weighted moving average (EWMA) control charts in the data that were autocorrelation. One researcher stated that this chart is not suitable if the same control limits are used in the case of independent variables. For this reason, it is necessary to apply the time series model in building the control chart. A classical control chart for independent variables is usually applied to residual processes. This procedure is permitted provided that residuals are independent. In 1978, Shewhart modification for the autoregressive process was introduced by using the distance between the sample mean and the target value compared to the standard deviation of the autocorrelation process. In this paper we will examine the mean of EWMA for autocorrelation process derived from Montgomery and Patel. Performance to be investigated was investigated by examining Average Run Length (ARL) based on the Markov Chain Method.

  2. The critical role of NIR spectroscopy and statistical process control (SPC) strategy towards captopril tablets (25 mg) manufacturing process understanding: a case study.

    PubMed

    Curtivo, Cátia Panizzon Dal; Funghi, Nathália Bitencourt; Tavares, Guilherme Diniz; Barbosa, Sávio Fujita; Löbenberg, Raimar; Bou-Chacra, Nádia Araci

    2015-05-01

    In this work, near-infrared spectroscopy (NIRS) method was used to evaluate the uniformity of dosage units of three captopril 25 mg tablets commercial batches. The performance of the calibration method was assessed by determination of Q value (0.9986), standard error of estimation (C-set SEE = 1.956), standard error of prediction (V-set SEP = 2.076) as well as the consistency (106.1%). These results indicated the adequacy of the selected model. The method validation revealed the agreement of the reference high pressure liquid chromatography (HPLC) and NIRS methods. The process evaluation using the NIRS method showed that the variability was due to common causes and delivered predictable results consistently. Cp and Cpk values were, respectively, 2.05 and 1.80. These results revealed a non-centered process in relation to the average target (100% w/w), in the specified range (85-115%). The probability of failure was 21:100 million tablets of captopril. The NIRS in combination with the method of multivariate calibration, partial least squares (PLS) regression, allowed the development of methodology for the uniformity of dosage units evaluation of captopril tablets 25 mg. The statistical process control strategy associated with NIRS method as PAT played a critical role in understanding of the sources and degree of variation and its impact on the process. This approach led towards a better process understanding and provided the sound scientific basis for its continuous improvement.

  3. The utilization of six sigma and statistical process control techniques in surgical quality improvement.

    PubMed

    Sedlack, Jeffrey D

    2010-01-01

    Surgeons have been slow to incorporate industrial reliability techniques. Process control methods were applied to surgeon waiting time between cases, and to length of stay (LOS) after colon surgery. Waiting times between surgeries were evaluated by auditing the operating room records of a single hospital over a 1-month period. The medical records of 628 patients undergoing colon surgery over a 5-year period were reviewed. The average surgeon wait time between cases was 53 min, and the busiest surgeon spent 291/2 hr in 1 month waiting between surgeries. Process control charting demonstrated poor overall control of the room turnover process. Average LOS after colon resection also demonstrated very poor control. Mean LOS was 10 days. Weibull's conditional analysis revealed a conditional LOS of 9.83 days. Serious process management problems were identified in both analyses. These process issues are both expensive and adversely affect the quality of service offered by the institution. Process control mechanisms were suggested or implemented to improve these surgical processes. Industrial reliability and quality management tools can easily and effectively identify process control problems that occur on surgical services. © 2010 National Association for Healthcare Quality.

  4. Vesicle-based method for collecting, manipulating, and chemically processing trace macromolecular species

    DOEpatents

    Davalos, Rafael V [Oakland, CA; Ellis, Christopher R. B. [Oakland, CA

    2010-08-17

    Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

  5. Vesicle-based method and apparatus for collecting, manipulating, and chemically processing trace macromolecular species

    DOEpatents

    Davalos, Rafael V [Oakland, CA; Ellis, Christopher R. B. [Oakland, CA

    2008-03-04

    Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

  6. 40 CFR 63.144 - Process wastewater provisions-test methods and procedures for determining applicability and Group...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Group 1/Group 2 determinations (determining which wastewater streams require control). (a... methods and procedures for determining applicability and Group 1/Group 2 determinations (determining which wastewater streams require control). 63.144 Section 63.144 Protection of Environment ENVIRONMENTAL PROTECTION...

  7. 40 CFR 63.144 - Process wastewater provisions-test methods and procedures for determining applicability and Group...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Group 1/Group 2 determinations (determining which wastewater streams require control). (a... methods and procedures for determining applicability and Group 1/Group 2 determinations (determining which wastewater streams require control). 63.144 Section 63.144 Protection of Environment ENVIRONMENTAL PROTECTION...

  8. 40 CFR 63.144 - Process wastewater provisions-test methods and procedures for determining applicability and Group...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Group 1/Group 2 determinations (determining which wastewater streams require control). (a... methods and procedures for determining applicability and Group 1/Group 2 determinations (determining which wastewater streams require control). 63.144 Section 63.144 Protection of Environment ENVIRONMENTAL PROTECTION...

  9. 40 CFR 63.144 - Process wastewater provisions-test methods and procedures for determining applicability and Group...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Group 1/Group 2 determinations (determining which wastewater streams require control). (a... methods and procedures for determining applicability and Group 1/Group 2 determinations (determining which wastewater streams require control). 63.144 Section 63.144 Protection of Environment ENVIRONMENTAL PROTECTION...

  10. 40 CFR 63.144 - Process wastewater provisions-test methods and procedures for determining applicability and Group...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Group 1/Group 2 determinations (determining which wastewater streams require control). (a... methods and procedures for determining applicability and Group 1/Group 2 determinations (determining which wastewater streams require control). 63.144 Section 63.144 Protection of Environment ENVIRONMENTAL PROTECTION...

  11. 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.

  12. Applying Standard Interfaces to a Process-Control Language

    NASA Technical Reports Server (NTRS)

    Berthold, Richard T.

    2005-01-01

    A method of applying open-operating-system standard interfaces to the NASA User Interface Language (UIL) has been devised. UIL is a computing language that can be used in monitoring and controlling automated processes: for example, the Timeliner computer program, written in UIL, is a general-purpose software system for monitoring and controlling sequences of automated tasks in a target system. In providing the major elements of connectivity between UIL and the target system, the present method offers advantages over the prior method. Most notably, unlike in the prior method, the software description of the target system can be made independent of the applicable compiler software and need not be linked to the applicable executable compiler image. Also unlike in the prior method, it is not necessary to recompile the source code and relink the source code to a new executable compiler image. Abstraction of the description of the target system to a data file can be defined easily, with intuitive syntax, and knowledge of the source-code language is not needed for the definition.

  13. A Proven Method for Meeting Export Control Objectives in Postal and Shipping Sectors

    DTIC Science & Technology

    2015-02-01

    Mellon University for the operation of the Software Engineering Institute, a federally funded research and development center sponsored by the United...Export Control at USPS 5 3.3 Objectives for Improving Export Screening at USPS 6 4 Development of the New Screening Process 7 4.1 “Walking the Model...Export Screening Development Process 10 Figure 2: Induction and Processing of International Mail 10 Figure 3: The Export Screening Process 11

  14. Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering

    PubMed Central

    Carmena, Jose M.

    2016-01-01

    Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain’s behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user’s motor intention during CLDA—a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter initialization. Finally, the architecture extended control to tasks beyond those used for CLDA training. These results have significant implications towards the development of clinically-viable neuroprosthetics. PMID:27035820

  15. Contamination-Free Manufacturing: Tool Component Qualification, Verification and Correlation with Wafers

    NASA Astrophysics Data System (ADS)

    Tan, Samantha H.; Chen, Ning; Liu, Shi; Wang, Kefei

    2003-09-01

    As part of the semiconductor industry "contamination-free manufacturing" effort, significant emphasis has been placed on reducing potential sources of contamination from process equipment and process equipment components. Process tools contain process chambers and components that are exposed to the process environment or process chemistry and in some cases are in direct contact with production wafers. Any contamination from these sources must be controlled or eliminated in order to maintain high process yields, device performance, and device reliability. This paper discusses new nondestructive analytical methods for quantitative measurement of the cleanliness of metal, quartz, polysilicon and ceramic components that are used in process equipment tools. The goal of these new procedures is to measure the effectiveness of cleaning procedures and to verify whether a tool component part is sufficiently clean for installation and subsequent routine use in the manufacturing line. These procedures provide a reliable "qualification method" for tool component certification and also provide a routine quality control method for reliable operation of cleaning facilities. Cost advantages to wafer manufacturing include higher yields due to improved process cleanliness and elimination of yield loss and downtime resulting from the installation of "bad" components in process tools. We also discuss a representative example of wafer contamination having been linked to a specific process tool component.

  16. Evaluation of pH monitoring as a method of processor control.

    PubMed

    Stears, J G; Gray, J E; Winkler, N T

    1979-01-01

    Sensitometry and pH values of the developer solution were compared in controlled over-replenishment, developer depletion, fixer contamination experiments, and on a daily quality control basis. The purpose of these comparisons was to evaluate the potential of pH monitoring as a method of processor control, or a supplement to sensitometry as a method of quality control. Reasonable correlation was found between pH values and film density in two of the three experiments but little or no correlation was found in the third experiment and on a day-to-day basis. The conclusion drawn from these comparisons is that pH monitoring has several limitations which render it unsuitable as a method of daily processor quality control as either a primary or supplementary technique. Sensitometry takes into account all the variables encountered in film processing and is the clear method of choice for processor quality control.

  17. Topographic and hydrographic survey data for the São Francisco River near Torrinha, Bahia, Brazil, 2014

    USGS Publications Warehouse

    Fosness, Ryan L.; Dietsch, Benjamin J.

    2015-10-21

    This report presents the surveying techniques and data-processing methods used to collect, process, and disseminate topographic and hydrographic data. All standard and non‑standard data-collection methods, techniques, and data process methods were documented. Additional discussion describes the quality-assurance and quality-control elements used in this study, along with the limitations for the Torrinha-Itacoatiara study reach data. The topographic and hydrographic geospatial data are published along with associated metadata.

  18. Manufacturing methods of a composite cell case for a Ni-Cd battery

    NASA Technical Reports Server (NTRS)

    Bauer, J. L.

    1979-01-01

    Basic manufacturing method refinements for using graphite epoxy material for a nickel cadmium battery cell case were performed to demonstrate production feasibility. The various facets of production scale-up, i.e., process and tooling development, together with material and process control, were integrated into a comprehensive manufacturing process that assures production reproducibility and product uniformity. Test results substantiate that a battery cell case produced from graphite epoxy pre-impregnated material, utilizing the internal pressure bag fabrication method, is feasible.

  19. Communication devices for network-hopping communications and methods of network-hopping communications

    DOEpatents

    Buttles, John W

    2013-04-23

    Wireless communication devices include a software-defined radio coupled to processing circuitry. The system controller is configured to execute computer programming code. Storage media is coupled to the system controller and includes computer programming code configured to cause the system controller to configure and reconfigure the software-defined radio to operate on each of a plurality of communication networks according to a selected sequence. Methods for communicating with a wireless device and methods of wireless network-hopping are also disclosed.

  20. A Quality Assurance Initiative for Commercial-Scale Production in High-Throughput Cryopreservation of Blue Catfish Sperm

    PubMed Central

    Hu, E; Liao, T. W.; Tiersch, T. R.

    2013-01-01

    Cryopreservation of fish sperm has been studied for decades at a laboratory (research) scale. However, high-throughput cryopreservation of fish sperm has recently been developed to enable industrial-scale production. This study treated blue catfish (Ictalurus furcatus) sperm high-throughput cryopreservation as a manufacturing production line and initiated quality assurance plan development. The main objectives were to identify: 1) the main production quality characteristics; 2) the process features for quality assurance; 3) the internal quality characteristics and their specification designs; 4) the quality control and process capability evaluation methods, and 5) the directions for further improvements and applications. The essential product quality characteristics were identified as fertility-related characteristics. Specification design which established the tolerance levels according to demand and process constraints was performed based on these quality characteristics. Meanwhile, to ensure integrity throughout the process, internal quality characteristics (characteristics at each quality control point within process) that could affect fertility-related quality characteristics were defined with specifications. Due to the process feature of 100% inspection (quality inspection of every fish), a specific calculation method, use of cumulative sum (CUSUM) control charts, was applied to monitor each quality characteristic. An index of overall process evaluation, process capacity, was analyzed based on in-control process and the designed specifications, which further integrates the quality assurance plan. With the established quality assurance plan, the process could operate stably and quality of products would be reliable. PMID:23872356

  1. Intermediate Cognitive Phenotypes in Bipolar Disorder

    PubMed Central

    Langenecker, Scott A.; Saunders, Erika F.H.; Kade, Allison M.; Ransom, Michael T.; McInnis, Melvin G.

    2013-01-01

    Background Intermediate cognitive phenotypes (ICPs) are measurable and quantifiable states that may be objectively assessed in a standardized method, and can be integrated into association studies, including genetic, biochemical, clinical, and imaging based correlates. The present study used neuropsychological measures as ICPs, with factor scores in executive functioning, attention, memory, fine motor function, and emotion processing, similar to prior work in schizophrenia. Methods Healthy control subjects (HC, n=34) and euthymic (E, n=66), depressed (D, n=43), or hypomanic/mixed (HM, n=13) patients with bipolar disorder (BD) were assessed with neuropsychological tests. These were from eight domains consistent with previous literature; auditory memory, visual memory, processing speed with interference resolution, verbal fluency and processing speed, conceptual reasoning and set-shifting, inhibitory control, emotion processing, and fine motor dexterity. Results Of the eight factor scores, the HC group outperformed the E group in three (Processing Speed with Interference Resolution, Visual Memory, Fine Motor Dexterity), the D group in seven (all except Inhibitory Control), and the HM group in four (Inhibitory Control, Processing Speed with Interference Resolution, Fine Motor Dexterity, and Auditory Memory). Limitations The HM group was relatively small, thus effects of this phase of illness may have been underestimated. Effects of medication could not be fully controlled without a randomized, double-blind, placebo-controlled study. Conclusions Use of the factor scores can assist in determining ICPs for BD and related disorders, and may provide more specific targets for development of new treatments. We highlight strong ICPs (Processing Speed with Interference Resolution, Visual Memory, Fine Motor Dexterity) for further study, consistent with the existing literature. PMID:19800130

  2. Towards better process understanding: chemometrics and multivariate measurements in manufacturing of solid dosage forms.

    PubMed

    Matero, Sanni; van Den Berg, Frans; Poutiainen, Sami; Rantanen, Jukka; Pajander, Jari

    2013-05-01

    The manufacturing of tablets involves many unit operations that possess multivariate and complex characteristics. The interactions between the material characteristics and process related variation are presently not comprehensively analyzed due to univariate detection methods. As a consequence, current best practice to control a typical process is to not allow process-related factors to vary i.e. lock the production parameters. The problem related to the lack of sufficient process understanding is still there: the variation within process and material properties is an intrinsic feature and cannot be compensated for with constant process parameters. Instead, a more comprehensive approach based on the use of multivariate tools for investigating processes should be applied. In the pharmaceutical field these methods are referred to as Process Analytical Technology (PAT) tools that aim to achieve a thorough understanding and control over the production process. PAT includes the frames for measurement as well as data analyzes and controlling for in-depth understanding, leading to more consistent and safer drug products with less batch rejections. In the optimal situation, by applying these techniques, destructive end-product testing could be avoided. In this paper the most prominent multivariate data analysis measuring tools within tablet manufacturing and basic research on operations are reviewed. Copyright © 2013 Wiley Periodicals, Inc.

  3. Simulated electronic heterodyne recording and processing of pulsed-laser holograms

    NASA Technical Reports Server (NTRS)

    Decker, A. J.

    1979-01-01

    The electronic recording of pulsed-laser holograms is proposed. The polarization sensitivity of each resolution element of the detector is controlled independently to add an arbitrary phase to the image waves. This method which can be used to simulate heterodyne recording and to process three-dimensional optical images, is based on a similar method for heterodyne recording and processing of continuous-wave holograms.

  4. Determining osmotic pressure of drug solutions by air humidity in equilibrium method.

    PubMed

    Zhan, Xiancheng; Li, Hui; Yu, Lan; Wei, Guocui; Li, Chengrong

    2014-06-01

    To establish a new osmotic pressure measuring method with a wide measuring range. The osmotic pressure of drug solutions is determined by measuring the relative air humidity in equilibrium with the solution. The freezing point osmometry is used as a control. The data obtained by the proposed method are comparable to those by the control method, and the measuring range of the proposed method is significantly wider than that of the control method. The proposed method is performed in an isothermal and equilibrium state, so it overcomes the defects of the freezing point and dew point osmometries which result from the heterothermal process in the measurement, and therefore is not limited to diluted solutions.

  5. Using the Multipole Resonance Probe to Stabilize the Electron Density During a Reactive Sputter Process

    NASA Astrophysics Data System (ADS)

    Oberberg, Moritz; Styrnoll, Tim; Ries, Stefan; Bienholz, Stefan; Awakowicz, Peter

    2015-09-01

    Reactive sputter processes are used for the deposition of hard, wear-resistant and non-corrosive ceramic layers such as aluminum oxide (Al2O3) . A well known problem is target poisoning at high reactive gas flows, which results from the reaction of the reactive gas with the metal target. Consequently, the sputter rate decreases and secondary electron emission increases. Both parameters show a non-linear hysteresis behavior as a function of the reactive gas flow and this leads to process instabilities. This work presents a new control method of Al2O3 deposition in a multiple frequency CCP (MFCCP) based on plasma parameters. Until today, process controls use parameters such as spectral line intensities of sputtered metal as an indicator for the sputter rate. A coupling between plasma and substrate is not considered. The control system in this work uses a new plasma diagnostic method: The multipole resonance probe (MRP) measures plasma parameters such as electron density by analyzing a typical resonance frequency of the system response. This concept combines target processes and plasma effects and directly controls the sputter source instead of the resulting target parameters.

  6. Enhanced IMC design of load disturbance rejection for integrating and unstable processes with slow dynamics.

    PubMed

    Liu, Tao; Gao, Furong

    2011-04-01

    In view of the deficiencies in existing internal model control (IMC)-based methods for load disturbance rejection for integrating and unstable processes with slow dynamics, a modified IMC-based controller design is proposed to deal with step- or ramp-type load disturbance that is often encountered in engineering practices. By classifying the ways through which such load disturbance enters into the process, analytical controller formulae are correspondingly developed, based on a two-degree-of-freedom (2DOF) control structure that allows for separate optimization of load disturbance rejection from setpoint tracking. An obvious merit is that there is only a single adjustable parameter in the proposed controller, which in essence corresponds to the time constant of the closed-loop transfer function for load disturbance rejection, and can be monotonically tuned to meet a good trade-off between disturbance rejection performance and closed-loop robust stability. At the same time, robust tuning constraints are given to accommodate process uncertainties in practice. Illustrative examples from the recent literature are used to show effectiveness and merits of the proposed method for different cases of load disturbance. Copyright © 2010. Published by Elsevier Ltd.

  7. Varied morphology carbon nanotubes and method for their manufacture

    DOEpatents

    Li, Wenzhi; Wen, Jian Guo; Ren, Zhi Feng

    2007-01-02

    The present invention describes the preparation of carbon nanotubes of varied morphology, catalyst materials for their synthesis. The present invention also describes reactor apparatus and methods of optimizing and controlling process parameters for the manufacture carbon nanotubes with pre-determined morphologies in relatively high purity and in high yields. In particular, the present invention provides methods for the preparation of non-aligned carbon nanotubes with controllable morphologies, catalyst materials and methods for their manufacture.

  8. Evaluation of strength-controlling defects in paper by stress concentration analyses

    Treesearch

    John M. Considine; David W. Vahey; James W. Evans; Kevin T. Turner; Robert E. Rowlands

    2011-01-01

    Cellulosic webs, such as paper materials, are composed of an interwoven, bonded network of cellulose fibers. Strength-controlling parameters in these webs are influenced by constituent fibers and method of processing and manufacture. Instead of estimating the effect on tensile strength of each processing/manufacturing variable, this study modifies and compares the...

  9. Using Statistical Process Control Charts to Study Stuttering Frequency Variability during a Single Day

    ERIC Educational Resources Information Center

    Karimi, Hamid; O'Brian, Sue; Onslow, Mark; Jones, Mark; Menzies, Ross; Packman, Ann

    2013-01-01

    Purpose: Stuttering varies between and within speaking situations. In this study, the authors used statistical process control charts with 10 case studies to investigate variability of stuttering frequency. Method: Participants were 10 adults who stutter. The authors counted the percentage of syllables stuttered (%SS) for segments of their speech…

  10. Vibration welding system with thin film sensor

    DOEpatents

    Cai, Wayne W; Abell, Jeffrey A; Li, Xiaochun; Choi, Hongseok; Zhao, Jingzhou

    2014-03-18

    A vibration welding system includes an anvil, a welding horn, a thin film sensor, and a process controller. The anvil and horn include working surfaces that contact a work piece during the welding process. The sensor measures a control value at the working surface. The measured control value is transmitted to the controller, which controls the system in part using the measured control value. The thin film sensor may include a plurality of thermopiles and thermocouples which collectively measure temperature and heat flux at the working surface. A method includes providing a welder device with a slot adjacent to a working surface of the welder device, inserting the thin film sensor into the slot, and using the sensor to measure a control value at the working surface. A process controller then controls the vibration welding system in part using the measured control value.

  11. Phytometric intelligence sensors

    NASA Technical Reports Server (NTRS)

    Seelig, Hans-Dieter (Inventor); Stoner, II, Richard J. (Inventor); Hoehn, Alexander (Inventor); Adams, III, William Walter (Inventor)

    2010-01-01

    Methods and apparatus for determining when plants require watering, and methods of attending to the watering of plants including signaling the grower that the plants are in need of hydration are provided. The novel methods include real-time measurement of plant metabolics and phytometric physiology changes of intrinsic physical or behavioral traits within the plant such as determining physiological flux measurement of enzyme flux due to environmental changes such as the wind and drought stress, soil and plant mineral deficiencies, or the interaction with a bio-control for organic disease control including, cell movement, signal transduction, internal chemical processes and external environmental processes including when plants require watering, and methods of attending to the watering of plants including signaling the grower that the plants are in need of hydration.

  12. The role of strategies in motor learning

    PubMed Central

    Taylor, Jordan A.; Ivry, Richard B.

    2015-01-01

    There has been renewed interest in the role of strategies in sensorimotor learning. The combination of new behavioral methods and computational methods has begun to unravel the interaction between processes related to strategic control and processes related to motor adaptation. These processes may operate on very different error signals. Strategy learning is sensitive to goal-based performance error. In contrast, adaptation is sensitive to prediction errors between the desired and actual consequences of a planned movement. The former guides what the desired movement should be, whereas the latter guides how to implement the desired movement. Whereas traditional approaches have favored serial models in which an initial strategy-based phase gives way to more automatized forms of control, it now seems that strategic and adaptive processes operate with considerable independence throughout learning, although the relative weight given the two processes will shift with changes in performance. As such, skill acquisition involves the synergistic engagement of strategic and adaptive processes. PMID:22329960

  13. Application of the user-centred design process according ISO 9241-210 in air traffic control.

    PubMed

    König, Christina; Hofmann, Thomas; Bruder, Ralph

    2012-01-01

    Designing a usable human machine interface for air traffic control is challenging and should follow approved methods. The ISO 9241-210 standard promises high usability of products by integrating future users and following an iterative process. This contribution describes the proceeding and first results of the analysis and application of ISO 9241-210 to develop a planning tool for air traffic controllers.

  14. Forced reeling of Bombyx mori silk: separating behavior and processing conditions.

    PubMed

    Mortimer, Beth; Holland, Chris; Vollrath, Fritz

    2013-10-14

    Controlled reeling is a powerful tool to investigate the details of silk processing. However, consistent forced reeling of silkworms is hindered by the significant degree of behaviorally induced variation caused by the animal. This paper proposes silkworm paralysis as a novel method to control the animal and thus in vivo spinning conditions. Using these methods, we achieve low and consistent reeling forces during the collection of over 500 m of individual silk fiber while monitoring filament variability, morphology, and properties. Novel techniques to measure the irregular silk cross-sectional areas lead to the more accurate calculation of the true engineering values and mechanical property variation of individual silk fibers. Combining controlled reeling and accurate thread measurement techniques allows us to present the relative contributions of processing and behavior in the performance envelope of Bombyx mori silk.

  15. [Feedforward control strategy and its application in quality improvement of ethanol precipitation process of danhong injection].

    PubMed

    Yan, Bin-Jun; Guo, Zheng-Tai; Qu, Hai-Bin; Zhao, Bu-Chang; Zhao, Tao

    2013-06-01

    In this work, a feedforward control strategy basing on the concept of quality by design was established for the manufacturing process of traditional Chinese medicine to reduce the impact of the quality variation of raw materials on drug. In the research, the ethanol precipitation process of Danhong injection was taken as an application case of the method established. Box-Behnken design of experiments was conducted. Mathematical models relating the attributes of the concentrate, the process parameters and the quality of the supernatants produced were established. Then an optimization model for calculating the best process parameters basing on the attributes of the concentrate was built. The quality of the supernatants produced by ethanol precipitation with optimized and non-optimized process parameters were compared. The results showed that using the feedforward control strategy for process parameters optimization can control the quality of the supernatants effectively. The feedforward control strategy proposed can enhance the batch-to-batch consistency of the supernatants produced by ethanol precipitation.

  16. High-throughput manufacturing of size-tuned liposomes by a new microfluidics method using enhanced statistical tools for characterization.

    PubMed

    Kastner, Elisabeth; Kaur, Randip; Lowry, Deborah; Moghaddam, Behfar; Wilkinson, Alexander; Perrie, Yvonne

    2014-12-30

    Microfluidics has recently emerged as a new method of manufacturing liposomes, which allows for reproducible mixing in miliseconds on the nanoliter scale. Here we investigate microfluidics-based manufacturing of liposomes. The aim of these studies was to assess the parameters in a microfluidic process by varying the total flow rate (TFR) and the flow rate ratio (FRR) of the solvent and aqueous phases. Design of experiment and multivariate data analysis were used for increased process understanding and development of predictive and correlative models. High FRR lead to the bottom-up synthesis of liposomes, with a strong correlation with vesicle size, demonstrating the ability to in-process control liposomes size; the resulting liposome size correlated with the FRR in the microfluidics process, with liposomes of 50 nm being reproducibly manufactured. Furthermore, we demonstrate the potential of a high throughput manufacturing of liposomes using microfluidics with a four-fold increase in the volumetric flow rate, maintaining liposome characteristics. The efficacy of these liposomes was demonstrated in transfection studies and was modelled using predictive modeling. Mathematical modelling identified FRR as the key variable in the microfluidic process, with the highest impact on liposome size, polydispersity and transfection efficiency. This study demonstrates microfluidics as a robust and high-throughput method for the scalable and highly reproducible manufacture of size-controlled liposomes. Furthermore, the application of statistically based process control increases understanding and allows for the generation of a design-space for controlled particle characteristics. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Self-organizing sensing and actuation for automatic control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cheng, George Shu-Xing

    A Self-Organizing Process Control Architecture is introduced with a Sensing Layer, Control Layer, Actuation Layer, Process Layer, as well as Self-Organizing Sensors (SOS) and Self-Organizing Actuators (SOA). A Self-Organizing Sensor for a process variable with one or multiple input variables is disclosed. An artificial neural network (ANN) based dynamic modeling mechanism as part of the Self-Organizing Sensor is described. As a case example, a Self-Organizing Soft-Sensor for CFB Boiler Bed Height is presented. Also provided is a method to develop a Self-Organizing Sensor.

  18. Continuous control of chaos based on the stability criterion.

    PubMed

    Yu, Hong Jie; Liu, Yan Zhu; Peng, Jian Hua

    2004-06-01

    A method of chaos control based on stability criterion is proposed in the present paper. This method can stabilize chaotic systems onto a desired periodic orbit by a small time-continuous perturbation nonlinear feedback. This method does not require linearization of the system around the stabilized orbit and only an approximate location of the desired periodic orbit is required which can be automatically detected in the control process. The control can be started at any moment by choosing appropriate perturbation restriction condition. It seems that more flexibility and convenience are the main advantages of this method. The discussions on control of attitude motion of a spacecraft, Rössler system, and two coupled Duffing oscillators are given as numerical examples.

  19. Researching on Control Device of Prestressing Wire Reinforcement

    NASA Astrophysics Data System (ADS)

    Si, Jianhui; Guo, Yangbo; Liu, Maoshe

    2017-06-01

    This paper mainly introduces a device for controlling prestress and its related research methods, the advantage of this method is that the reinforcement process is easy to operate and control the prestress of wire rope accurately. The relationship between the stress and strain of the steel wire rope is monitored during the experiment, and the one - to - one relationship between the controllable position and the pretightening force of the steel wire rope is confirmed by the 5mm steel wire rope, and the results are analyzed theoretically by the measured elastic modulus. The results show that the method can effectively control the prestressing force, and the result provides a reference method for strengthening the concrete column with prestressed steel strand.

  20. Method for controlling gas metal arc welding

    DOEpatents

    Smartt, H.B.; Einerson, C.J.; Watkins, A.D.

    1987-08-10

    The heat input and mass input in a Gas Metal Arc welding process are controlled by a method that comprises calculating appropriate values for weld speed, filler wire feed rate and an expected value for the welding current by algorithmic function means, applying such values for weld speed and filler wire feed rate to the welding process, measuring the welding current, comparing the measured current to the calculated current, using said comparison to calculate corrections for the weld speed and filler wire feed rate, and applying corrections. 3 figs., 1 tab.

  1. Oil shale derived pollutant control materials and methods and apparatuses for producing and utilizing the same

    DOEpatents

    Boardman, Richard D.; Carrington, Robert A.

    2010-05-04

    Pollution control substances may be formed from the combustion of oil shale, which may produce a kerogen-based pyrolysis gas and shale sorbent, each of which may be used to reduce, absorb, or adsorb pollutants in pollution producing combustion processes, pyrolysis processes, or other reaction processes. Pyrolysis gases produced during the combustion or gasification of oil shale may also be used as a combustion gas or may be processed or otherwise refined to produce synthetic gases and fuels.

  2. Use of artificial intelligence in the production of high quality minced meat

    NASA Astrophysics Data System (ADS)

    Kapovsky, B. R.; Pchelkina, V. A.; Plyasheshnik, P. I.; Dydykin, A. S.; Lazarev, A. A.

    2017-09-01

    A design for an automatic line for minced meat production according to new production technology based on an innovative meat milling method is proposed. This method allows the necessary degree of raw material comminution at the stage of raw material preparation to be obtained, which leads to production intensification due to the traditional meat mass comminution equipment being unnecessary. To ensure consistent quality of the product obtained, the use of on-line automatic control of the technological process for minced meat production is envisaged. This system has been developed using artificial intelligence methods and technologies. The system is trainable during the operation process, adapts to changes in processed raw material characteristics and to external impacts that affect the system operation, and manufactures meat shavings with minimal dispersion of the typical particle size. The control system includes equipment for express analysis of the chemical composition of the minced meat and its temperature after comminution. In this case, the minced meat production process can be controlled strictly as a function of time, which excludes subjective factors for assessing the degree of finished product readiness. This will allow finished meat products with consistent, targeted high quality to be produced.

  3. Self-assembly and hierarchical patterning of aligned organic nanowire arrays by solvent evaporation on substrates with patterned wettability.

    PubMed

    Bao, Rong-Rong; Zhang, Cheng-Yi; Zhang, Xiu-Juan; Ou, Xue-Mei; Lee, Chun-Sing; Jie, Jian-Sheng; Zhang, Xiao-Hong

    2013-06-26

    The controlled growth and alignment of one-dimensional organic nanostructures at well-defined locations considerably hinders the integration of nanostructures for electronic and optoelectronic applications. Here, we demonstrate a simple process to achieve the growth, alignment, and hierarchical patterning of organic nanowires on substrates with controlled patterns of surface wettability. The first-level pattern is confined by the substrate patterns of wettability. Organic nanostructures are preferentially grown on solvent wettable regions. The second-level pattern is the patterning of aligned organic nanowires deposited by controlling the shape and movement of the solution contact lines during evaporation on the wettable regions. This process is controlled by the cover-hat-controlled method or vertical evaportation method. Therefore, various new patterns of organic nanostructures can be obtained by combing these two levels of patterns. This simple method proves to be a general approach that can be applied to other organic nanostructure systems. Using the as-prepared patterned nanowire arrays, an optoelectronic device (photodetector) is easily fabricated. Hence, the proposed simple, large-scale, low-cost method of preparing patterns of highly ordered organic nanostructures has high potential applications in various electronic and optoelectronic devices.

  4. Factors influencing tests of auditory processing: a perspective on current issues and relevant concerns.

    PubMed

    Cacace, Anthony T; McFarland, Dennis J

    2013-01-01

    Tests of auditory perception, such as those used in the assessment of central auditory processing disorders ([C]APDs), represent a domain in audiological assessment where measurement of this theoretical construct is often confounded by nonauditory abilities due to methodological shortcomings. These confounds include the effects of cognitive variables such as memory and attention and suboptimal testing paradigms, including the use of verbal reproduction as a form of response selection. We argue that these factors need to be controlled more carefully and/or modified so that their impact on tests of auditory and visual perception is only minimal. To advocate for a stronger theoretical framework than currently exists and to suggest better methodological strategies to improve assessment of auditory processing disorders (APDs). Emphasis is placed on adaptive forced-choice psychophysical methods and the use of matched tasks in multiple sensory modalities to achieve these goals. Together, this approach has potential to improve the construct validity of the diagnosis, enhance and develop theory, and evolve into a preferred method of testing. Examination of methods commonly used in studies of APDs. Where possible, currently used methodology is compared to contemporary psychophysical methods that emphasize computer-controlled forced-choice paradigms. In many cases, the procedures used in studies of APD introduce confounding factors that could be minimized if computer-controlled forced-choice psychophysical methods were utilized. Ambiguities of interpretation, indeterminate diagnoses, and unwanted confounds can be avoided by minimizing memory and attentional demands on the input end and precluding the use of response-selection strategies that use complex motor processes on the output end. Advocated are the use of computer-controlled forced-choice psychophysical paradigms in combination with matched tasks in multiple sensory modalities to enhance the prospect of obtaining a valid diagnosis. American Academy of Audiology.

  5. DEVELOPMENT OF INFRARED METHODS FOR CHARACTERIZATION OF INORGANIC SULFUR SPECIES RELATED TO INJECTION DESULFURIZATION PROCESSES

    EPA Science Inventory

    Current methods designed to control and reduce the amount of sulfur dioxide emitted into the atmosphere from coal-fired power plants and factories rely upon the reaction between SO2 and alkaline earth compounds and are called flue gas desulfurization (FGD) processes. Of these met...

  6. Processes, Procedures, and Methods to Control Pollution Resulting from Silvicultural Activities.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Water Programs.

    This report presents brief documentation of silvicultural practices, both those now in use and those in stages of research and development. A majority of the text is concerned with the specific aspects of silvicultural activities which relate to nonpoint source pollution control methods. Analyzed are existing and near future pollution control…

  7. System and method for secure group transactions

    DOEpatents

    Goldsmith, Steven Y [Rochester, MN

    2006-04-25

    A method and a secure system, processing on one or more computers, provides a way to control a group transaction. The invention uses group consensus access control and multiple distributed secure agents in a network environment. Each secure agent can organize with the other secure agents to form a secure distributed agent collective.

  8. Design, implementation and application of distributed order PI control.

    PubMed

    Zhou, Fengyu; Zhao, Yang; Li, Yan; Chen, YangQuan

    2013-05-01

    In this paper, a series of distributed order PI controller design methods are derived and applied to the robust control of wheeled service robots, which can tolerate more structural and parametric uncertainties than the corresponding fractional order PI control. A practical discrete incremental distributed order PI control strategy is proposed basing on the discretization method and the frequency criterions, which can be commonly used in many fields of fractional order system, control and signal processing. Besides, an auto-tuning strategy and the genetic algorithm are applied to the distributed order PI control as well. A number of experimental results are provided to show the advantages and distinguished features of the discussed methods in fairways. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Proceedings of the 3rd Annual SCOLE Workshop

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr. (Compiler)

    1987-01-01

    Topics addressed include: modeling and controlling the Spacecraft Control Laboratory Experiment (SCOLE) configurations; slewing maneuvers; mathematical models; vibration damping; gravitational effects; structural dynamics; finite element method; distributed parameter system; on-line pulse control; stability augmentation; and stochastic processes.

  10. Controlled release from drug microparticles via solventless dry-polymer coating.

    PubMed

    Capece, Maxx; Barrows, Jason; Davé, Rajesh N

    2015-04-01

    A novel solvent-less dry-polymer coating process employing high-intensity vibrations avoiding the use of liquid plasticizers, solvents, binders, and heat treatments is utilized for the purpose of controlled release. The main hypothesis is that such process having highly controllable processing intensity and time may be effective for coating particularly fine particles, 100 μm and smaller via exploiting particle interactions between polymers and substrates in the dry state, while avoiding breakage yet achieving conformal coating. The method utilizes vibratory mixing to first layer micronized polymer onto active pharmaceutical ingredient (API) particles by virtue of van der Waals forces and to subsequently mechanically deform the polymer into a continuous film. As a practical example, ascorbic acid and ibuprofen microparticles, 50-500 μm, are coated with the polymers polyethylene wax or carnauba wax, a generally recognized as safe material, resulting in controlled release on the order of seconds to hours. As a novelty, models are utilized to describe the coating layer thickness and the controlled-release behavior of the API, which occurs because of a diffusion-based mechanism. Such modeling would allow the design and control of the coating process with application for the controlled release of microparticles, particularly those less than 100 μm, which are difficult to coat by conventional solvent coating methods. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  11. Simulation of process identification and controller tuning for flow control system

    NASA Astrophysics Data System (ADS)

    Chew, I. M.; Wong, F.; Bono, A.; Wong, K. I.

    2017-06-01

    PID controller is undeniably the most popular method used in controlling various industrial processes. The feature to tune the three elements in PID has allowed the controller to deal with specific needs of the industrial processes. This paper discusses the three elements of control actions and improving robustness of controllers through combination of these control actions in various forms. A plant model is simulated using the Process Control Simulator in order to evaluate the controller performance. At first, the open loop response of the plant is studied by applying a step input to the plant and collecting the output data from the plant. Then, FOPDT of physical model is formed by using both Matlab-Simulink and PRC method. Then, calculation of controller’s setting is performed to find the values of Kc and τi that will give satisfactory control in closed loop system. Then, the performance analysis of closed loop system is obtained by set point tracking analysis and disturbance rejection performance. To optimize the overall physical system performance, a refined tuning of PID or detuning is further conducted to ensure a consistent resultant output of closed loop system reaction to the set point changes and disturbances to the physical model. As a result, the PB = 100 (%) and τi = 2.0 (s) is preferably chosen for setpoint tracking while PB = 100 (%) and τi = 2.5 (s) is selected for rejecting the imposed disturbance to the model. In a nutshell, selecting correlation tuning values is likewise depended on the required control’s objective for the stability performance of overall physical model.

  12. Chemometrics-based process analytical technology (PAT) tools: applications and adaptation in pharmaceutical and biopharmaceutical industries.

    PubMed

    Challa, Shruthi; Potumarthi, Ravichandra

    2013-01-01

    Process analytical technology (PAT) is used to monitor and control critical process parameters in raw materials and in-process products to maintain the critical quality attributes and build quality into the product. Process analytical technology can be successfully implemented in pharmaceutical and biopharmaceutical industries not only to impart quality into the products but also to prevent out-of-specifications and improve the productivity. PAT implementation eliminates the drawbacks of traditional methods which involves excessive sampling and facilitates rapid testing through direct sampling without any destruction of sample. However, to successfully adapt PAT tools into pharmaceutical and biopharmaceutical environment, thorough understanding of the process is needed along with mathematical and statistical tools to analyze large multidimensional spectral data generated by PAT tools. Chemometrics is a chemical discipline which incorporates both statistical and mathematical methods to obtain and analyze relevant information from PAT spectral tools. Applications of commonly used PAT tools in combination with appropriate chemometric method along with their advantages and working principle are discussed. Finally, systematic application of PAT tools in biopharmaceutical environment to control critical process parameters for achieving product quality is diagrammatically represented.

  13. An Improved Method to Control the Critical Parameters of a Multivariable Control System

    NASA Astrophysics Data System (ADS)

    Subha Hency Jims, P.; Dharmalingam, S.; Wessley, G. Jims John

    2017-10-01

    The role of control systems is to cope with the process deficiencies and the undesirable effect of the external disturbances. Most of the multivariable processes are highly iterative and complex in nature. Aircraft systems, Modern Power Plants, Refineries, Robotic systems are few such complex systems that involve numerous critical parameters that need to be monitored and controlled. Control of these important parameters is not only tedious and cumbersome but also is crucial from environmental, safety and quality perspective. In this paper, one such multivariable system, namely, a utility boiler has been considered. A modern power plant is a complex arrangement of pipework and machineries with numerous interacting control loops and support systems. In this paper, the calculation of controller parameters based on classical tuning concepts has been presented. The controller parameters thus obtained and employed has controlled the critical parameters of a boiler during fuel switching disturbances. The proposed method can be applied to control the critical parameters like elevator, aileron, rudder, elevator trim rudder and aileron trim, flap control systems of aircraft systems.

  14. A mathematical theory of learning control for linear discrete multivariable systems

    NASA Technical Reports Server (NTRS)

    Phan, Minh; Longman, Richard W.

    1988-01-01

    When tracking control systems are used in repetitive operations such as robots in various manufacturing processes, the controller will make the same errors repeatedly. Here consideration is given to learning controllers that look at the tracking errors in each repetition of the process and adjust the control to decrease these errors in the next repetition. A general formalism is developed for learning control of discrete-time (time-varying or time-invariant) linear multivariable systems. Methods of specifying a desired trajectory (such that the trajectory can actually be performed by the discrete system) are discussed, and learning controllers are developed. Stability criteria are obtained which are relatively easy to use to insure convergence of the learning process, and proper gain settings are discussed in light of measurement noise and system uncertainties.

  15. Evaluating the quality of a cell counting measurement process via a dilution series experimental design.

    PubMed

    Sarkar, Sumona; Lund, Steven P; Vyzasatya, Ravi; Vanguri, Padmavathy; Elliott, John T; Plant, Anne L; Lin-Gibson, Sheng

    2017-12-01

    Cell counting measurements are critical in the research, development and manufacturing of cell-based products, yet determining cell quantity with accuracy and precision remains a challenge. Validating and evaluating a cell counting measurement process can be difficult because of the lack of appropriate reference material. Here we describe an experimental design and statistical analysis approach to evaluate the quality of a cell counting measurement process in the absence of appropriate reference materials or reference methods. The experimental design is based on a dilution series study with replicate samples and observations as well as measurement process controls. The statistical analysis evaluates the precision and proportionality of the cell counting measurement process and can be used to compare the quality of two or more counting methods. As an illustration of this approach, cell counting measurement processes (automated and manual methods) were compared for a human mesenchymal stromal cell (hMSC) preparation. For the hMSC preparation investigated, results indicated that the automated method performed better than the manual counting methods in terms of precision and proportionality. By conducting well controlled dilution series experimental designs coupled with appropriate statistical analysis, quantitative indicators of repeatability and proportionality can be calculated to provide an assessment of cell counting measurement quality. This approach does not rely on the use of a reference material or comparison to "gold standard" methods known to have limited assurance of accuracy and precision. The approach presented here may help the selection, optimization, and/or validation of a cell counting measurement process. Published by Elsevier Inc.

  16. Control by quality: proposition of a typology.

    PubMed

    Pujo, P; Pillet, M

    The application of Quality tools and methods in industrial management has always had a fundamental impact on the control of production. It influences the behavior of the actors concerned, while introducing the necessary notions and formalizations, especially for production systems with little or no automation, which constitute a large part of the industrial activity. Several quality approaches are applied in the workshop and are implemented at the level of the control. In this paper, the authors present a typology of the various approaches that have successively influenced control, such as statistical process control, quality assurance, and continuous improvement. First the authors present a parallel between production control and quality organizational structure. They note the duality between control, which is aimed at increasing productivity, and quality, which aims to satisfy the needs of the customer. They also note the hierarchical organizational structure of these two systems of management with, at each level, the notion of a feedback loop. This notion is fundamental to any kind of decision making. The paper is organized around the operational, tactical, and strategic levels, by describing for each level the main methods and tools for control by quality. The overview of these tools and methods starts at the operational level, with the Statistical Process Control, the Taguchi technique, and the "six sigma" approach. On the tactical level, we find a quality system approach, with a documented description of the procedures introduced in the firm. The management system can refer here to Quality Assurance, Total Productive Maintenance, or Management by Total Quality. The formalization through procedures of the rules of decision governing the process control enhances the validity of these rules. This leads to the enhancement of their reliability and to their consolidation. All this counterbalances the human, intrinsically fluctuating, behavior of the control operators. Strategic control by quality is then detailed, and the two main approaches, the continuous improvement approach and the proactive improvement approach, are introduced. Finally, the authors observe that at each of the three levels, the continuous process improvement, which is a component of Total Quality, becomes an essential preoccupation for the control. Ultimately, the recursive utilization of the Deming cycle remains the best practice for the control by quality.

  17. Systems and methods for data quality control and cleansing

    DOEpatents

    Wenzel, Michael; Boettcher, Andrew; Drees, Kirk; Kummer, James

    2016-05-31

    A method for detecting and cleansing suspect building automation system data is shown and described. The method includes using processing electronics to automatically determine which of a plurality of error detectors and which of a plurality of data cleansers to use with building automation system data. The method further includes using processing electronics to automatically detect errors in the data and cleanse the data using a subset of the error detectors and a subset of the cleansers.

  18. Method and system for controlling a synchronous machine over full operating range

    DOEpatents

    Walters, James E.; Gunawan, Fani S.; Xue, Yanhong

    2002-01-01

    System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

  19. Surface hardening of Al alloys through controlled ball-milling and sintering.

    PubMed

    Kim, Seek Hyeoun; Kim, Yong Jin; Ahn, Jung-Ho

    2012-07-01

    One of the drawbacks of aluminum and its alloys is the lack of proper heat-treatment for surface-hardening. In the present work, a new and simple method of hardening the surface of aluminum and its alloys was developed. Low-energy ball-milling using specific process control agents (PCAs) was employed, using subsequent sintering in a controlled atmosphere. The PCAs in the present work were very effective both for milling and the formation of hard nanocrystalline dispersoids during sintering. The residual oxygen in a sintering atmosphere also played an important role in the formation of AIN or Al-O-N dispersoids. Through the proper control of the processing atmosphere and PCAs, the hardness and thickness of the hardened layers could be adjusted. The results of the wear test showed that the present aluminum alloys can be effectively utilized as light-weight components with a good wear resistance. Furthermore, the present method involves a simple forming process of die-compaction and sintering.

  20. Grain Structure Control of Additively Manufactured Metallic Materials

    PubMed Central

    Faierson, Eric J.

    2017-01-01

    Grain structure control is challenging for metal additive manufacturing (AM). Grain structure optimization requires the control of grain morphology with grain size refinement, which can improve the mechanical properties of additive manufactured components. This work summarizes methods to promote fine equiaxed grains in both the additive manufacturing process and subsequent heat treatment. Influences of temperature gradient, solidification velocity and alloy composition on grain morphology are discussed. Equiaxed solidification is greatly promoted by introducing a high density of heterogeneous nucleation sites via powder rate control in the direct energy deposition (DED) technique or powder surface treatment for powder-bed techniques. Grain growth/coarsening during post-processing heat treatment can be restricted by presence of nano-scale oxide particles formed in-situ during AM. Grain refinement of martensitic steels can also be achieved by cyclic austenitizing in post-processing heat treatment. Evidently, new alloy powder design is another sustainable method enhancing the capability of AM for high-performance components with desirable microstructures.

  1. Cell-controlled hybrid perfusion fed-batch CHO cell process provides significant productivity improvement over conventional fed-batch cultures.

    PubMed

    Hiller, Gregory W; Ovalle, Ana Maria; Gagnon, Matthew P; Curran, Meredith L; Wang, Wenge

    2017-07-01

    A simple method originally designed to control lactate accumulation in fed-batch cultures of Chinese Hamster Ovary (CHO) cells has been modified and extended to allow cells in culture to control their own rate of perfusion to precisely deliver nutritional requirements. The method allows for very fast expansion of cells to high density while using a minimal volume of concentrated perfusion medium. When the short-duration cell-controlled perfusion is performed in the production bioreactor and is immediately followed by a conventional fed-batch culture using highly concentrated feeds, the overall productivity of the culture is approximately doubled when compared with a highly optimized state-of-the-art fed-batch process. The technology was applied with near uniform success to five CHO cell processes producing five different humanized monoclonal antibodies. The increases in productivity were due to the increases in sustained viable cell densities. Biotechnol. Bioeng. 2017;114: 1438-1447. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. Design of distributed systems of hydrolithosphere processes management. A synthesis of distributed management systems

    NASA Astrophysics Data System (ADS)

    Pershin, I. M.; Pervukhin, D. A.; Ilyushin, Y. V.; Afanaseva, O. V.

    2017-10-01

    The paper considers an important problem of designing distributed systems of hydrolithosphere processes management. The control actions on the hydrolithosphere processes under consideration are implemented by a set of extractive wells. The article shows the method of defining the approximation links for description of the dynamic characteristics of hydrolithosphere processes. The structure of distributed regulators, used in the management systems by the considered processes, is presented. The paper analyses the results of the synthesis of the distributed management system and the results of modelling the closed-loop control system by the parameters of the hydrolithosphere process.

  3. Development of NIRS method for quality control of drug combination artesunate–azithromycin for the treatment of severe malaria

    PubMed Central

    Boyer, Chantal; Gaudin, Karen; Kauss, Tina; Gaubert, Alexandra; Boudis, Abdelhakim; Verschelden, Justine; Franc, Mickaël; Roussille, Julie; Boucher, Jacques; Olliaro, Piero; White, Nicholas J.; Millet, Pascal; Dubost, Jean-Pierre

    2012-01-01

    Near infrared spectroscopy (NIRS) methods were developed for the determination of analytical content of an antimalarial-antibiotic (artesunate and azithromycin) co-formulation in hard gelatin capsule (HGC). The NIRS consists of pre-processing treatment of spectra (raw spectra and first-derivation of two spectral zones), a unique principal component analysis model to ensure the specificity and then two partial least-squares regression models for the determination content of each active pharmaceutical ingredient. The NIRS methods were developed and validated with no reference method, since the manufacturing process of HGC is basically mixed excipients with active pharmaceutical ingredients. The accuracy profiles showed β-expectation tolerance limits within the acceptance limits (±5%). The analytical control approach performed by reversed phase (HPLC) required two different methods involving two different preparation and chromatographic methods. NIRS offers advantages in terms of lower costs of equipment and procedures, time saving, environmentally friendly. PMID:22579599

  4. System-wide hybrid MPC-PID control of a continuous pharmaceutical tablet manufacturing process via direct compaction.

    PubMed

    Singh, Ravendra; Ierapetritou, Marianthi; Ramachandran, Rohit

    2013-11-01

    The next generation of QbD based pharmaceutical products will be manufactured through continuous processing. This will allow the integration of online/inline monitoring tools, coupled with an efficient advanced model-based feedback control systems, to achieve precise control of process variables, so that the predefined product quality can be achieved consistently. The direct compaction process considered in this study is highly interactive and involves time delays for a number of process variables due to sensor placements, process equipment dimensions, and the flow characteristics of the solid material. A simple feedback regulatory control system (e.g., PI(D)) by itself may not be sufficient to achieve the tight process control that is mandated by regulatory authorities. The process presented herein comprises of coupled dynamics involving slow and fast responses, indicating the requirement of a hybrid control scheme such as a combined MPC-PID control scheme. In this manuscript, an efficient system-wide hybrid control strategy for an integrated continuous pharmaceutical tablet manufacturing process via direct compaction has been designed. The designed control system is a hybrid scheme of MPC-PID control. An effective controller parameter tuning strategy involving an ITAE method coupled with an optimization strategy has been used for tuning of both MPC and PID parameters. The designed hybrid control system has been implemented in a first-principles model-based flowsheet that was simulated in gPROMS (Process System Enterprise). Results demonstrate enhanced performance of critical quality attributes (CQAs) under the hybrid control scheme compared to only PID or MPC control schemes, illustrating the potential of a hybrid control scheme in improving pharmaceutical manufacturing operations. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Research on width control of Metal Fused-coating Additive Manufacturing based on active control

    NASA Astrophysics Data System (ADS)

    Ren, Chuan qi; Wei, Zheng ying; Wang, Xin; Du, Jun; Zhang, Shan; Zhang, Zhitong; Bai, Hao

    2017-12-01

    Given the stability of the shape of the forming layer is one of the key problems that affect the final quality of the sample morphology, taking a study on the forming process and the control method of morphology make a significant difference to metal fused-coating additive manufacturing (MFCAM) in achieving the efficient and stable forming. To improve the quality and precision of the samples of single-layer single pass, a control method of morphology based on active control was established by this paper. The real-time acquisition of image was realized by CCD and the characteristics of morphology of the forming process were simultaneously extracted. Making analysis of the characteristics of the width during the process, the relationship between the relative difference of different frames and moving speed was given. A large number of experiments are used to verify the response speed and accuracy of the system. The results show that the active system can improve the morphology of the sample and the smoothness of the width of the single channel, and increase the uniformity of width by 55.16%.

  6. Parental Perceptions of Neighborhood Processes, Stress, Personal Control, and Risk for Physical Child Abuse and Neglect

    ERIC Educational Resources Information Center

    Guterman, Neil B.; Lee, Shawna J.; Taylor, Catherine A.; Rathouz, Paul J.

    2009-01-01

    Objective: This study set out to examine whether mothers' individual perceptions of their neighborhood social processes predict their risk for physical child abuse and neglect directly and/or indirectly via pathways involving parents' reported stress and sense of personal control in the parenting role. Methods: In-home and phone interview data…

  7. How to collect and process large polyhedral viruses of insects

    Treesearch

    W. D. Rollinson; F. B. Lewis

    1962-01-01

    Polyhedral viruses have proved highly effective and very practical for control of certain pine sawflies; and a method of collecting and processing the small polyhedra (5 microns or less) characteristic of sawflies has been described. There is experimental evidence that the virus diseases of many Lepidopterous insects can be used similarly for direct control. The...

  8. A Study on Human Oriented Autonomous Distributed Manufacturing System —Real-time Scheduling Method Based on Preference of Human Operators

    NASA Astrophysics Data System (ADS)

    Iwamura, Koji; Kuwahara, Shinya; Tanimizu, Yoshitaka; Sugimura, Nobuhiro

    Recently, new distributed architectures of manufacturing systems are proposed, aiming at realizing more flexible control structures of the manufacturing systems. Many researches have been carried out to deal with the distributed architectures for planning and control of the manufacturing systems. However, the human operators have not yet been discussed for the autonomous components of the distributed manufacturing systems. A real-time scheduling method is proposed, in this research, to select suitable combinations of the human operators, the resources and the jobs for the manufacturing processes. The proposed scheduling method consists of following three steps. In the first step, the human operators select their favorite manufacturing processes which they will carry out in the next time period, based on their preferences. In the second step, the machine tools and the jobs select suitable combinations for the next machining processes. In the third step, the automated guided vehicles and the jobs select suitable combinations for the next transportation processes. The second and third steps are carried out by using the utility value based method and the dispatching rule-based method proposed in the previous researches. Some case studies have been carried out to verify the effectiveness of the proposed method.

  9. Method and device for diagnosing and controlling combustion instabilities in internal combustion engines operating in or transitioning to homogeneous charge combustion ignition mode

    DOEpatents

    Wagner, Robert M [Knoxville, TN; Daw, Charles S [Knoxville, TN; Green, Johney B [Knoxville, TN; Edwards, Kevin D [Knoxville, TN

    2008-10-07

    This invention is a method of achieving stable, optimal mixtures of HCCI and SI in practical gasoline internal combustion engines comprising the steps of: characterizing the combustion process based on combustion process measurements, determining the ratio of conventional and HCCI combustion, determining the trajectory (sequence) of states for consecutive combustion processes, and determining subsequent combustion process modifications using said information to steer the engine combustion toward desired behavior.

  10. A scalable, fully automated process for construction of sequence-ready human exome targeted capture libraries

    PubMed Central

    2011-01-01

    Genome targeting methods enable cost-effective capture of specific subsets of the genome for sequencing. We present here an automated, highly scalable method for carrying out the Solution Hybrid Selection capture approach that provides a dramatic increase in scale and throughput of sequence-ready libraries produced. Significant process improvements and a series of in-process quality control checkpoints are also added. These process improvements can also be used in a manual version of the protocol. PMID:21205303

  11. A method of setting limits for the purpose of quality assurance

    NASA Astrophysics Data System (ADS)

    Sanghangthum, Taweap; Suriyapee, Sivalee; Kim, Gwe-Ya; Pawlicki, Todd

    2013-10-01

    The result from any assurance measurement needs to be checked against some limits for acceptability. There are two types of limits; those that define clinical acceptability (action limits) and those that are meant to serve as a warning that the measurement is close to the action limits (tolerance limits). Currently, there is no standard procedure to set these limits. In this work, we propose an operational procedure to set tolerance limits and action limits. The approach to establish the limits is based on techniques of quality engineering using control charts and a process capability index. The method is different for tolerance limits and action limits with action limits being categorized into those that are specified and unspecified. The procedure is to first ensure process control using the I-MR control charts. Then, the tolerance limits are set equal to the control chart limits on the I chart. Action limits are determined using the Cpm process capability index with the requirements that the process must be in-control. The limits from the proposed procedure are compared to an existing or conventional method. Four examples are investigated: two of volumetric modulated arc therapy (VMAT) point dose quality assurance (QA) and two of routine linear accelerator output QA. The tolerance limits range from about 6% larger to 9% smaller than conventional action limits for VMAT QA cases. For the linac output QA, tolerance limits are about 60% smaller than conventional action limits. The operational procedure describe in this work is based on established quality management tools and will provide a systematic guide to set up tolerance and action limits for different equipment and processes.

  12. Macro-/Micro-Controlled 3D Lithium-Ion Batteries via Additive Manufacturing and Electric Field Processing.

    PubMed

    Li, Jie; Liang, Xinhua; Liou, Frank; Park, Jonghyun

    2018-01-30

    This paper presents a new concept for making battery electrodes that can simultaneously control macro-/micro-structures and help address current energy storage technology gaps and future energy storage requirements. Modern batteries are fabricated in the form of laminated structures that are composed of randomly mixed constituent materials. This randomness in conventional methods can provide a possibility of developing new breakthrough processing techniques to build well-organized structures that can improve battery performance. In the proposed processing, an electric field (EF) controls the microstructures of manganese-based electrodes, while additive manufacturing controls macro-3D structures and the integration of both scales. The synergistic control of micro-/macro-structures is a novel concept in energy material processing that has considerable potential for providing unprecedented control of electrode structures, thereby enhancing performance. Electrochemical tests have shown that these new electrodes exhibit superior performance in their specific capacity, areal capacity, and life cycle.

  13. Properties of TiNi intermetallic compound industrially produced by combustion synthesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaieda, Yoshinari

    Most TiNi shape memory intermetallic compounds are conventionally produced by the process including high frequency induction vacuum melting and casting. A gravity segregation occurs in a cast TiNi ingot because of the big difference in the specific gravity between Ti and Ni. It is difficult to control accurately the phase transformation temperature of TiNi shape memory intermetallic compound produced by the conventional process, because the martensitic transformation temperature shifts by 10K due to the change in 0.1 % of Ni content. Homogeneous TiNi intermetallic compound is produced by the industrial process including combustion synthesis method, which is a newly developedmore » manufacturing process. In the new process, phase transformation temperatures of TiNi can be controlled accurately by controlling the ratio of Ti and Ni elemental starting powders. The chemical component, the impurities and the phase transformation temperatures of the TiNi products industrially produced by the process are revealed. These properties are vitally important when combustion synthesis method is applied to an industrial mass production process for producing TiNi shape memory intermetallic compounds. TiNi shape memory products are industrially and commercially produced today the industrial process including combustion synthesis. The total production weight in a year is 30 tins in 1994.« less

  14. Elements for successful sensor-based process control {Integrated Metrology}

    NASA Astrophysics Data System (ADS)

    Butler, Stephanie Watts

    1998-11-01

    Current productivity needs have stimulated development of alternative metrology, control, and equipment maintenance methods. Specifically, sensor applications provide the opportunity to increase productivity, tighten control, reduce scrap, and improve maintenance schedules and procedures. Past experience indicates a complete integrated solution must be provided for sensor-based control to be used successfully in production. In this paper, Integrated Metrology is proposed as the term for an integrated solution that will result in a successful application of sensors for process control. This paper defines and explores the perceived four elements of successful sensor applications: business needs, integration, components, and form. Based upon analysis of existing successful commercially available controllers, the necessary business factors have been determined to be strong, measurable industry-wide business needs whose solution is profitable and feasible. This paper examines why the key aspect of integration is the decision making process. A detailed discussion is provided of the components of most importance to sensor based control: decision-making methods, the 3R's of sensors, and connectivity. A metric for one of the R's (resolution) is proposed to allow focus on this important aspect of measurement. A form for these integrated components which synergistically partitions various aspects of control at the equipment and MES levels to efficiently achieve desired benefits is recommended.

  15. Cognitive task load in a naval ship control centre: from identification to prediction.

    PubMed

    Grootjen, M; Neerincx, M A; Veltman, J A

    Deployment of information and communication technology will lead to further automation of control centre tasks and an increasing amount of information to be processed. A method for establishing adequate levels of cognitive task load for the operators in such complex environments has been developed. It is based on a model distinguishing three load factors: time occupied, task-set switching, and level of information processing. Application of the method resulted in eight scenarios for eight extremes of task load (i.e. low and high values for each load factor). These scenarios were performed by 13 teams in a high-fidelity control centre simulator of the Royal Netherlands Navy. The results show that the method provides good prediction of the task load that will actually appear in the simulator. The model allowed identification of under- and overload situations showing negative effects on operator performance corresponding to controlled experiments in a less realistic task environment. Tools proposed to keep the operator at an optimum task load are (adaptive) task allocation and interface support.

  16. A method for using unmanned aerial vehicles for emergency investigation of single geo-hazards and sample applications of this method

    NASA Astrophysics Data System (ADS)

    Huang, Haifeng; Long, Jingjing; Yi, Wu; Yi, Qinglin; Zhang, Guodong; Lei, Bangjun

    2017-11-01

    In recent years, unmanned aerial vehicles (UAVs) have become widely used in emergency investigations of major natural hazards over large areas; however, UAVs are less commonly employed to investigate single geo-hazards. Based on a number of successful investigations in the Three Gorges Reservoir area, China, a complete UAV-based method for performing emergency investigations of single geo-hazards is described. First, a customized UAV system that consists of a multi-rotor UAV subsystem, an aerial photography subsystem, a ground control subsystem and a ground surveillance subsystem is described in detail. The implementation process, which includes four steps, i.e., indoor preparation, site investigation, on-site fast processing and application, and indoor comprehensive processing and application, is then elaborated, and two investigation schemes, automatic and manual, that are used in the site investigation step are put forward. Moreover, some key techniques and methods - e.g., the layout and measurement of ground control points (GCPs), route planning, flight control and image collection, and the Structure from Motion (SfM) photogrammetry processing - are explained. Finally, three applications are given. Experience has shown that using UAVs for emergency investigation of single geo-hazards greatly reduces the time, intensity and risks associated with on-site work and provides valuable, high-accuracy, high-resolution information that supports emergency responses.

  17. Quality control for quantitative PCR based on amplification compatibility test.

    PubMed

    Tichopad, Ales; Bar, Tzachi; Pecen, Ladislav; Kitchen, Robert R; Kubista, Mikael; Pfaffl, Michael W

    2010-04-01

    Quantitative qPCR is a routinely used method for the accurate quantification of nucleic acids. Yet it may generate erroneous results if the amplification process is obscured by inhibition or generation of aberrant side-products such as primer dimers. Several methods have been established to control for pre-processing performance that rely on the introduction of a co-amplified reference sequence, however there is currently no method to allow for reliable control of the amplification process without directly modifying the sample mix. Herein we present a statistical approach based on multivariate analysis of the amplification response data generated in real-time. The amplification trajectory in its most resolved and dynamic phase is fitted with a suitable model. Two parameters of this model, related to amplification efficiency, are then used for calculation of the Z-score statistics. Each studied sample is compared to a predefined reference set of reactions, typically calibration reactions. A probabilistic decision for each individual Z-score is then used to identify the majority of inhibited reactions in our experiments. We compare this approach to univariate methods using only the sample specific amplification efficiency as reporter of the compatibility. We demonstrate improved identification performance using the multivariate approach compared to the univariate approach. Finally we stress that the performance of the amplification compatibility test as a quality control procedure depends on the quality of the reference set. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Advanced Control Synthesis for Reverse Osmosis Water Desalination Processes.

    PubMed

    Phuc, Bui Duc Hong; You, Sam-Sang; Choi, Hyeung-Six; Jeong, Seok-Kwon

    2017-11-01

      In this study, robust control synthesis has been applied to a reverse osmosis desalination plant whose product water flow and salinity are chosen as two controlled variables. The reverse osmosis process has been selected to study since it typically uses less energy than thermal distillation. The aim of the robust design is to overcome the limitation of classical controllers in dealing with large parametric uncertainties, external disturbances, sensor noises, and unmodeled process dynamics. The analyzed desalination process is modeled as a multi-input multi-output (MIMO) system with varying parameters. The control system is decoupled using a feed forward decoupling method to reduce the interactions between control channels. Both nominal and perturbed reverse osmosis systems have been analyzed using structured singular values for their stabilities and performances. Simulation results show that the system responses meet all the control requirements against various uncertainties. Finally the reduced order controller provides excellent robust performance, with achieving decoupling, disturbance attenuation, and noise rejection. It can help to reduce the membrane cleanings, increase the robustness against uncertainties, and lower the energy consumption for process monitoring.

  19. Advanced process control framework initiative

    NASA Astrophysics Data System (ADS)

    Hill, Tom; Nettles, Steve

    1997-01-01

    The semiconductor industry, one the world's most fiercely competitive industries, is driven by increasingly complex process technologies and global competition to improve cycle time, quality, and process flexibility. Due to the complexity of these problems, current process control techniques are generally nonautomated, time-consuming, reactive, nonadaptive, and focused on individual fabrication tools and processes. As the semiconductor industry moves into higher density processes, radical new approaches are required. To address the need for advanced factory-level process control in this environment, Honeywell, Advanced Micro Devices (AMD), and SEMATECH formed the Advanced Process Control Framework Initiative (APCFI) joint research project. The project defines and demonstrates an Advanced Process Control (APC) approach based on SEMATECH's Computer Integrated Manufacturing (CIM) Framework. Its scope includes the coordination of Manufacturing Execution Systems, process control tools, and wafer fabrication equipment to provide necessary process control capabilities. Moreover, it takes advantage of the CIM Framework to integrate and coordinate applications from other suppliers that provide services necessary for the overall system to function. This presentation discusses the key concept of model-based process control that differentiates the APC Framework. This major improvement over current methods enables new systematic process control by linking the knowledge of key process settings to desired product characteristics that reside in models created with commercial model development tools The unique framework-based approach facilitates integration of commercial tools and reuse of their data by tying them together in an object-based structure. The presentation also explores the perspective of each organization's involvement in the APCFI project. Each has complementary goals and expertise to contribute; Honeywell represents the supplier viewpoint, AMD represents the user with 'real customer requirements', and SEMATECH provides a consensus-building organization that widely disseminates technology to suppliers and users in the semiconductor industry that face similar equipment and factory control systems challenges.

  20. Evaluation of extreme temperature events in northern Spain based on process control charts

    NASA Astrophysics Data System (ADS)

    Villeta, M.; Valencia, J. L.; Saá, A.; Tarquis, A. M.

    2018-02-01

    Extreme climate events have recently attracted the attention of a growing number of researchers because these events impose a large cost on agriculture and associated insurance planning. This study focuses on extreme temperature events and proposes a new method for their evaluation based on statistical process control tools, which are unusual in climate studies. A series of minimum and maximum daily temperatures for 12 geographical areas of a Spanish region between 1931 and 2009 were evaluated by applying statistical process control charts to statistically test whether evidence existed for an increase or a decrease of extreme temperature events. Specification limits were determined for each geographical area and used to define four types of extreme anomalies: lower and upper extremes for the minimum and maximum anomalies. A new binomial Markov extended process that considers the autocorrelation between extreme temperature events was generated for each geographical area and extreme anomaly type to establish the attribute control charts for the annual fraction of extreme days and to monitor the occurrence of annual extreme days. This method was used to assess the significance of changes and trends of extreme temperature events in the analysed region. The results demonstrate the effectiveness of an attribute control chart for evaluating extreme temperature events. For example, the evaluation of extreme maximum temperature events using the proposed statistical process control charts was consistent with the evidence of an increase in maximum temperatures during the last decades of the last century.

  1. Reinforcement learning for partially observable dynamic processes: adaptive dynamic programming using measured output data.

    PubMed

    Lewis, F L; Vamvoudakis, Kyriakos G

    2011-02-01

    Approximate dynamic programming (ADP) is a class of reinforcement learning methods that have shown their importance in a variety of applications, including feedback control of dynamical systems. ADP generally requires full information about the system internal states, which is usually not available in practical situations. In this paper, we show how to implement ADP methods using only measured input/output data from the system. Linear dynamical systems with deterministic behavior are considered herein, which are systems of great interest in the control system community. In control system theory, these types of methods are referred to as output feedback (OPFB). The stochastic equivalent of the systems dealt with in this paper is a class of partially observable Markov decision processes. We develop both policy iteration and value iteration algorithms that converge to an optimal controller that requires only OPFB. It is shown that, similar to Q -learning, the new methods have the important advantage that knowledge of the system dynamics is not needed for the implementation of these learning algorithms or for the OPFB control. Only the order of the system, as well as an upper bound on its "observability index," must be known. The learned OPFB controller is in the form of a polynomial autoregressive moving-average controller that has equivalent performance with the optimal state variable feedback gain.

  2. Cybernetic Basis and System Practice of Remote Sensing and Spatial Information Science

    NASA Astrophysics Data System (ADS)

    Tan, X.; Jing, X.; Chen, R.; Ming, Z.; He, L.; Sun, Y.; Sun, X.; Yan, L.

    2017-09-01

    Cybernetics provides a new set of ideas and methods for the study of modern science, and it has been fully applied in many areas. However, few people have introduced cybernetics into the field of remote sensing. The paper is based on the imaging process of remote sensing system, introducing cybernetics into the field of remote sensing, establishing a space-time closed-loop control theory for the actual operation of remote sensing. The paper made the process of spatial information coherently, and improved the comprehensive efficiency of the space information from acquisition, procession, transformation to application. We not only describes the application of cybernetics in remote sensing platform control, sensor control, data processing control, but also in whole system of remote sensing imaging process control. We achieve the information of output back to the input to control the efficient operation of the entire system. This breakthrough combination of cybernetics science and remote sensing science will improve remote sensing science to a higher level.

  3. Manufacturing methods of a composite cell case for a Ni-Cd battery

    NASA Technical Reports Server (NTRS)

    Bauer, J. L.; Bogner, R. S.; Lowe, E. P.; Orlowski, E.

    1979-01-01

    Graphite epoxy material for a nickel cadmium battery cell case has been evaluated and determined to perform in the simulated environment of the battery. The basic manufacturing method requires refinement to demonstrate production feasibility. The various facets of production scale-up, i.e., process and tooling development together with material and process control, have been integrated into a comprehensive manufacturing process that assures production reproducibility and product uniformity. Test results substantiate that a battery cell case produced from graphite epoxy pre-impregnated material utilizing internal pressure bag fabrication method is feasible.

  4. Energy saving control strategies for Haliscomenobacter hydrossis filamentous sludge bulking in the A/O process treating real low carbon/nitrogen domestic wastewater.

    PubMed

    Jiao, Erlong; Gao, Chundi; Li, Renfei; Tian, Ye; Peng, Yongzhen

    2017-07-16

    The control strategies of energy saving for filamentous sludge bulking were investigated in the A/O process under low dissolved oxygen (DO) with low carbon/nitrogen (C/N) ratio, and the dominant filamentous bacteria were identified by using fluorescent in situ hybridization. Initially, the sludge volume index reached nearly 500 mL/g and serious bulking occurred when the DO value was 0.5 mg/L, with Haliscomenobacter hydrossis as the major filamentous bacteria in the bulking sludge. Later on, the compartment number increased in the aerobic zone, increasing by this way DO, to control serious bulking. Increasing DO to 1 mg/L based on the increase of compartment number in the aerobic zone was the favorable controlling method, which solved the sludge loss, improved the effluent quality to the national discharge standard and allowed for energy costs saving. As a result, the effective control method for H. hydrossis filamentous sludge bulking provided the economical, convenient and longstanding method for most municipal wastewater treatment plants treating real low C/N domestic wastewater.

  5. Measuring and improving the quality of postoperative epidural analgesia for major abdominal surgery using statistical process control charts.

    PubMed

    Duncan, Fiona; Haigh, Carol

    2013-10-01

    To explore and improve the quality of continuous epidural analgesia for pain relief using Statistical Process Control tools. Measuring the quality of pain management interventions is complex. Intermittent audits do not accurately capture the results of quality improvement initiatives. The failure rate for one intervention, epidural analgesia, is approximately 30% in everyday practice, so it is an important area for improvement. Continuous measurement and analysis are required to understand the multiple factors involved in providing effective pain relief. Process control and quality improvement Routine prospectively acquired data collection started in 2006. Patients were asked about their pain and side effects of treatment. Statistical Process Control methods were applied for continuous data analysis. A multidisciplinary group worked together to identify reasons for variation in the data and instigated ideas for improvement. The key measure for improvement was a reduction in the percentage of patients with an epidural in severe pain. The baseline control charts illustrated the recorded variation in the rate of several processes and outcomes for 293 surgical patients. The mean visual analogue pain score (VNRS) was four. There was no special cause variation when data were stratified by surgeons, clinical area or patients who had experienced pain before surgery. Fifty-seven per cent of patients were hypotensive on the first day after surgery. We were able to demonstrate a significant improvement in the failure rate of epidurals as the project continued with quality improvement interventions. Statistical Process Control is a useful tool for measuring and improving the quality of pain management. The applications of Statistical Process Control methods offer the potential to learn more about the process of change and outcomes in an Acute Pain Service both locally and nationally. We have been able to develop measures for improvement and benchmarking in routine care that has led to the establishment of a national pain registry. © 2013 Blackwell Publishing Ltd.

  6. Quality status display for a vibration welding process

    DOEpatents

    Spicer, John Patrick; Abell, Jeffrey A.; Wincek, Michael Anthony; Chakraborty, Debejyo; Bracey, Jennifer; Wang, Hui; Tavora, Peter W.; Davis, Jeffrey S.; Hutchinson, Daniel C.; Reardon, Ronald L.; Utz, Shawn

    2017-03-28

    A system includes a host machine and a status projector. The host machine is in electrical communication with a collection of sensors and with a welding controller that generates control signals for controlling the welding horn. The host machine is configured to execute a method to thereby process the sensory and control signals, as well as predict a quality status of a weld that is formed using the welding horn, including identifying any suspect welds. The host machine then activates the status projector to illuminate the suspect welds. This may occur directly on the welds using a laser projector, or on a surface of the work piece in proximity to the welds. The system and method may be used in the ultrasonic welding of battery tabs of a multi-cell battery pack in a particular embodiment. The welding horn and welding controller may also be part of the system.

  7. Practical Use of Operation Data in the Process Industry

    NASA Astrophysics Data System (ADS)

    Kano, Manabu

    This paper aims to reveal real problems in the process industry and introduce recent development to solve such problems from the viewpoint of effective use of operation data. Two topics are discussed: virtual sensor and process control. First, in order to clarify the present state and problems, a part of our recent questionnaire survey of process control is quoted. It is emphasized that maintenance is a key issue not only for soft-sensors but also for controllers. Then, new techniques are explained. The first one is correlation-based just-in-time modeling (CoJIT), which can realize higher prediction performance than conventional methods and simplify model maintenance. The second is extended fictitious reference iterative tuning (E-FRIT), which can realize data-driven PID control parameter tuning without process modeling. The great usefulness of these techniques are demonstrated through their industrial applications.

  8. Multifractal Properties of Process Control Variables

    NASA Astrophysics Data System (ADS)

    Domański, Paweł D.

    2017-06-01

    Control system is an inevitable element of any industrial installation. Its quality affects overall process performance significantly. The assessment, whether control system needs any improvement or not, requires relevant and constructive measures. There are various methods, like time domain based, Minimum Variance, Gaussian and non-Gaussian statistical factors, fractal and entropy indexes. Majority of approaches use time series of control variables. They are able to cover many phenomena. But process complexities and human interventions cause effects that are hardly visible for standard measures. It is shown that the signals originating from industrial installations have multifractal properties and such an analysis may extend standard approach to further observations. The work is based on industrial and simulation data. The analysis delivers additional insight into the properties of control system and the process. It helps to discover internal dependencies and human factors, which are hardly detectable.

  9. Detection of malondialdehyde in processed meat products without interference from the ingredients.

    PubMed

    Jung, Samooel; Nam, Ki Chang; Jo, Cheorun

    2016-10-15

    Our aim was to develop a method for accurate quantification of malondialdehyde (MDA) in meat products. MDA content of uncured ground pork (Control); ground pork cured with sodium nitrite (Nitrite); and ground pork cured with sodium nitrite, sodium chloride, sodium pyrophosphate, maltodextrin, and a sausage seasoning (Mix) was measured by the 2-thiobarbituric acid (TBA) assay with MDA extraction by trichloroacetic acid (method A) and two high-performance liquid chromatography (HPLC) methods: i) HPLC separation of the MDA-dinitrophenyl hydrazine adduct (method B) and ii) HPLC separation of MDA (method C) after MDA extraction with acetonitrile. Methods A and B could not quantify MDA accurately in groups Nitrite and Mix. Nevertheless, MDA in groups Control, Nitrite, and Mix was accurately quantified by method C with good recovery. Therefore, direct MDA quantification by HPLC after MDA extraction with acetonitrile (method C) is useful for accurate measurement of MDA content in processed meat products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Multi-tasking arbitration and behaviour design for human-interactive robots

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yuichi; Onishi, Masaki; Hosoe, Shigeyuki; Luo, Zhiwei

    2013-05-01

    Robots that interact with humans in household environments are required to handle multiple real-time tasks simultaneously, such as carrying objects, collision avoidance and conversation with human. This article presents a design framework for the control and recognition processes to meet these requirements taking into account stochastic human behaviour. The proposed design method first introduces a Petri net for synchronisation of multiple tasks. The Petri net formulation is converted to Markov decision processes and processed in an optimal control framework. Three tasks (safety confirmation, object conveyance and conversation) interact and are expressed by the Petri net. Using the proposed framework, tasks that normally tend to be designed by integrating many if-then rules can be designed in a systematic manner in a state estimation and optimisation framework from the viewpoint of the shortest time optimal control. The proposed arbitration method was verified by simulations and experiments using RI-MAN, which was developed for interactive tasks with humans.

  11. Noncontact conductivity and dielectric measurement for high throughput roll-to-roll nanomanufacturing

    NASA Astrophysics Data System (ADS)

    Orloff, Nathan D.; Long, Christian J.; Obrzut, Jan; Maillaud, Laurent; Mirri, Francesca; Kole, Thomas P.; McMichael, Robert D.; Pasquali, Matteo; Stranick, Stephan J.; Alexander Liddle, J.

    2015-11-01

    Advances in roll-to-roll processing of graphene and carbon nanotubes have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible and wearable electronics, woven fabrics, and wires. These applications often require specific electrical properties, and hence precise control over material micro- and nanostructure. While such control can be achieved, in principle, by closed-loop processing methods, there are relatively few noncontact and nondestructive options for quantifying the electrical properties of materials on a moving web at the speed required in modern nanomanufacturing. Here, we demonstrate a noncontact microwave method for measuring the dielectric constant and conductivity (or geometry for samples of known dielectric properties) of materials in a millisecond. Such measurement times are compatible with current and future industrial needs, enabling real-time materials characterization and in-line control of processing variables without disrupting production.

  12. The Application of Linear and Nonlinear Water Tanks Case Study in Teaching of Process Control

    NASA Astrophysics Data System (ADS)

    Li, Xiangshun; Li, Zhiang

    2018-02-01

    In the traditional process control teaching, the importance of passing knowledge is emphasized while the development of creative and practical abilities of students is ignored. Traditional teaching methods are not very helpful to breed a good engineer. Case teaching is a very useful way to improve students’ innovative and practical abilities. In the traditional case teaching, knowledge points are taught separately based on different examples or no examples, thus it is very hard to setup the whole knowledge structure. Though all the knowledge is learned, how to use the knowledge to solve engineering problems keeps challenging for students. In this paper, the linear and nonlinear tanks are taken as illustrative examples which involves several knowledge points of process control. The application method of each knowledge point is discussed in detail and simulated. I believe the case-based study will be helpful for students.

  13. Noncontact conductivity and dielectric measurement for high throughput roll-to-roll nanomanufacturing

    PubMed Central

    Orloff, Nathan D.; Long, Christian J.; Obrzut, Jan; Maillaud, Laurent; Mirri, Francesca; Kole, Thomas P.; McMichael, Robert D.; Pasquali, Matteo; Stranick, Stephan J.; Alexander Liddle, J.

    2015-01-01

    Advances in roll-to-roll processing of graphene and carbon nanotubes have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible and wearable electronics, woven fabrics, and wires. These applications often require specific electrical properties, and hence precise control over material micro- and nanostructure. While such control can be achieved, in principle, by closed-loop processing methods, there are relatively few noncontact and nondestructive options for quantifying the electrical properties of materials on a moving web at the speed required in modern nanomanufacturing. Here, we demonstrate a noncontact microwave method for measuring the dielectric constant and conductivity (or geometry for samples of known dielectric properties) of materials in a millisecond. Such measurement times are compatible with current and future industrial needs, enabling real-time materials characterization and in-line control of processing variables without disrupting production. PMID:26592441

  14. Development of Chemical Process Design and Control for ...

    EPA Pesticide Factsheets

    This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation and decision making for the optimization of process operations to minimize environmental impacts associated with products, materials, and energy. The implemented control strategy combines a biologically inspired method with optimal control concepts for finding more sustainable operating trajectories. The sustainability assessment of process operating points is carried out by using the U.S. E.P.A.’s Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a multi-Objective Process Evaluator (GREENSCOPE) tool that provides scores for the selected indicators in the economic, material efficiency, environmental and energy areas. The indicator scores describe process performance on a sustainability measurement scale, effectively determining which operating point is more sustainable if there are more than several steady states for one specific product manufacturing. Through comparisons between a representative benchmark and the optimal steady-states obtained through implementation of the proposed controller, a systematic decision can be made in terms of whether the implementation of the controller is moving the process towards a more sustainable operation. The effectiveness of the proposed framework is illustrated through a case study of a continuous fermentation process for fuel production, whose materi

  15. Non-destructive control of graphite electrodes with use of current displacement effect

    NASA Astrophysics Data System (ADS)

    Myatezh, A. V.; Malozyomov, B. V.; Smirnov, M. A.

    2017-10-01

    The work is devoted to methods of nondestructive diagnostics and their use for solving the problem of diagnosing various defects in solid surface of graphite electrodes used in steelmaking furnaces. Various non-destructive control methods of materials are analyzed. In the article, methods of eddy-current defectoscopy of graphite electrodes are considered. Rationalization of the sensitivity increase of the method and localization of damage is described. Imitating modeling of electromagnetic processes was executed; results were made and conclusions were drawn.

  16. Methods of Adapting Digital Content for the Learning Process via Mobile Devices

    ERIC Educational Resources Information Center

    Lopez, J. L. Gimenez; Royo, T. Magal; Laborda, Jesus Garcia; Calvo, F. Garde

    2009-01-01

    This article analyses different methods of adapting digital content for its delivery via mobile devices taking into account two aspects which are a fundamental part of the learning process; on the one hand, functionality of the contents, and on the other, the actual controlled navigation requirements that the learner needs in order to acquire high…

  17. The Effect of Process Oriented Guided Inquiry Learning (POGIL) on 11th Graders' Conceptual Understanding of Electrochemistry

    ERIC Educational Resources Information Center

    Sen, Senol; Yilmaz, Ayhan; Geban, Ömer

    2016-01-01

    The purpose of this study was to investigate the effect of Process Oriented Guided Inquiry Learning (POGIL) method compared to traditional teaching method on 11th grade students' conceptual understanding of electrochemistry concepts. Participants were 115 students from a public school in Turkey. Nonequivalent control group design was used. Two…

  18. Optimum target sizes for a sequential sawing process

    Treesearch

    H. Dean Claxton

    1972-01-01

    A method for solving a class of problems in random sequential processes is presented. Sawing cedar pencil blocks is used to illustrate the method. Equations are developed for the function representing loss from improper sizing of blocks. A weighted over-all distribution for sawing and drying operations is developed and graphed. Loss minimizing changes in the control...

  19. Spectroscopic analysis and control

    DOEpatents

    Tate; , James D.; Reed, Christopher J.; Domke, Christopher H.; Le, Linh; Seasholtz, Mary Beth; Weber, Andy; Lipp, Charles

    2017-04-18

    Apparatus for spectroscopic analysis which includes a tunable diode laser spectrometer having a digital output signal and a digital computer for receiving the digital output signal from the spectrometer, the digital computer programmed to process the digital output signal using a multivariate regression algorithm. In addition, a spectroscopic method of analysis using such apparatus. Finally, a method for controlling an ethylene cracker hydrogenator.

  20. Preprocessing with Photoshop Software on Microscopic Images of A549 Cells in Epithelial-Mesenchymal Transition.

    PubMed

    Ren, Zhou-Xin; Yu, Hai-Bin; Shen, Jun-Ling; Li, Ya; Li, Jian-Sheng

    2015-06-01

    To establish a preprocessing method for cell morphometry in microscopic images of A549 cells in epithelial-mesenchymal transition (EMT). Adobe Photoshop CS2 (Adobe Systems, Inc.) was used for preprocessing the images. First, all images were processed for size uniformity and high distinguishability between the cell and background area. Then, a blank image with the same size and grids was established and cross points of the grids were added into a distinct color. The blank image was merged into a processed image. In the merged images, the cells with 1 or more cross points were chosen, and then the cell areas were enclosed and were replaced in a distinct color. Except for chosen cellular areas, all areas were changed into a unique hue. Three observers quantified roundness of cells in images with the image preprocess (IPP) or without the method (Controls), respectively. Furthermore, 1 observer measured the roundness 3 times with the 2 methods, respectively. The results between IPPs and Controls were compared for repeatability and reproducibility. As compared with the Control method, among 3 observers, use of the IPP method resulted in a higher number and a higher percentage of same-chosen cells in an image. The relative average deviation values of roundness, either for 3 observers or 1 observer, were significantly higher in Controls than in IPPs (p < 0.01 or 0.001). The values of intraclass correlation coefficient, both in Single Type or Average, were higher in IPPs than in Controls both for 3 observers and 1 observer. Processed with Adobe Photoshop, a chosen cell from an image was more objective, regular, and accurate, creating an increase of reproducibility and repeatability on morphometry of A549 cells in epithelial to mesenchymal transition.

  1. A method for evaluating treatment quality using in vivo EPID dosimetry and statistical process control in radiation therapy.

    PubMed

    Fuangrod, Todsaporn; Greer, Peter B; Simpson, John; Zwan, Benjamin J; Middleton, Richard H

    2017-03-13

    Purpose Due to increasing complexity, modern radiotherapy techniques require comprehensive quality assurance (QA) programmes, that to date generally focus on the pre-treatment stage. The purpose of this paper is to provide a method for an individual patient treatment QA evaluation and identification of a "quality gap" for continuous quality improvement. Design/methodology/approach A statistical process control (SPC) was applied to evaluate treatment delivery using in vivo electronic portal imaging device (EPID) dosimetry. A moving range control chart was constructed to monitor the individual patient treatment performance based on a control limit generated from initial data of 90 intensity-modulated radiotherapy (IMRT) and ten volumetric-modulated arc therapy (VMAT) patient deliveries. A process capability index was used to evaluate the continuing treatment quality based on three quality classes: treatment type-specific, treatment linac-specific, and body site-specific. Findings The determined control limits were 62.5 and 70.0 per cent of the χ pass-rate for IMRT and VMAT deliveries, respectively. In total, 14 patients were selected for a pilot study the results of which showed that about 1 per cent of all treatments contained errors relating to unexpected anatomical changes between treatment fractions. Both rectum and pelvis cancer treatments demonstrated process capability indices were less than 1, indicating the potential for quality improvement and hence may benefit from further assessment. Research limitations/implications The study relied on the application of in vivo EPID dosimetry for patients treated at the specific centre. Sampling patients for generating the control limits were limited to 100 patients. Whilst the quantitative results are specific to the clinical techniques and equipment used, the described method is generally applicable to IMRT and VMAT treatment QA. Whilst more work is required to determine the level of clinical significance, the authors have demonstrated the capability of the method for both treatment specific QA and continuing quality improvement. Practical implications The proposed method is a valuable tool for assessing the accuracy of treatment delivery whilst also improving treatment quality and patient safety. Originality/value Assessing in vivo EPID dosimetry with SPC can be used to improve the quality of radiation treatment for cancer patients.

  2. On Efficient Multigrid Methods for Materials Processing Flows with Small Particles

    NASA Technical Reports Server (NTRS)

    Thomas, James (Technical Monitor); Diskin, Boris; Harik, VasylMichael

    2004-01-01

    Multiscale modeling of materials requires simulations of multiple levels of structural hierarchy. The computational efficiency of numerical methods becomes a critical factor for simulating large physical systems with highly desperate length scales. Multigrid methods are known for their superior efficiency in representing/resolving different levels of physical details. The efficiency is achieved by employing interactively different discretizations on different scales (grids). To assist optimization of manufacturing conditions for materials processing with numerous particles (e.g., dispersion of particles, controlling flow viscosity and clusters), a new multigrid algorithm has been developed for a case of multiscale modeling of flows with small particles that have various length scales. The optimal efficiency of the algorithm is crucial for accurate predictions of the effect of processing conditions (e.g., pressure and velocity gradients) on the local flow fields that control the formation of various microstructures or clusters.

  3. Quantitative naturalistic methods for detecting change points in psychotherapy research: an illustration with alliance ruptures.

    PubMed

    Eubanks-Carter, Catherine; Gorman, Bernard S; Muran, J Christopher

    2012-01-01

    Analysis of change points in psychotherapy process could increase our understanding of mechanisms of change. In particular, naturalistic change point detection methods that identify turning points or breakpoints in time series data could enhance our ability to identify and study alliance ruptures and resolutions. This paper presents four categories of statistical methods for detecting change points in psychotherapy process: criterion-based methods, control chart methods, partitioning methods, and regression methods. Each method's utility for identifying shifts in the alliance is illustrated using a case example from the Beth Israel Psychotherapy Research program. Advantages and disadvantages of the various methods are discussed.

  4. Methods of synthesizing hydroxyapatite powders and bulk materials

    DOEpatents

    Luo, Ping

    1999-01-12

    Methods are provided for producing non-porous controlled morphology hydroxyapatite granules of less than 8 .mu.m by a spray-drying process. Solid or hollow spheres or doughnuts can be formed by controlling the volume fraction and viscosity of the slurry as well as the spray-drying conditions. Methods of providing for homogenous cellular structure hydroxyapatite granules are also provided. Pores or channels or varying size and number can be formed by varying the temperature at which a hydroxyapatite slurry formed in basic, saturated ammonium hydroxide is spray-dried. Methods of providing non-porous controlled morphology hydroxyapatite granules in ammonium hydroxide are also provided. The hydroxyapatite granules and bulk materials formed by these methods are also provided.

  5. Methods of synthesizing hydroxyapatite powders and bulk materials

    DOEpatents

    Luo, P.

    1999-01-12

    Methods are provided for producing non-porous controlled morphology hydroxyapatite granules of less than 8 {micro}m by a spray-drying process. Solid or hollow spheres or doughnuts can be formed by controlling the volume fraction and viscosity of the slurry as well as the spray-drying conditions. Methods of providing for homogeneous cellular structure hydroxyapatite granules are also provided. Pores or channels or varying size and number can be formed by varying the temperature at which a hydroxyapatite slurry formed in basic, saturated ammonium hydroxide is spray-dried. Methods of providing non-porous controlled morphology hydroxyapatite granules in ammonium hydroxide are also provided. The hydroxyapatite granules and bulk materials formed by these methods are also provided. 26 figs.

  6. The Co-simulation of Humanoid Robot Based on Solidworks, ADAMS and Simulink

    NASA Astrophysics Data System (ADS)

    Song, Dalei; Zheng, Lidan; Wang, Li; Qi, Weiwei; Li, Yanli

    A simulation method of adaptive controller is proposed for the humanoid robot system based on co-simulation of Solidworks, ADAMS and Simulink. A complex mathematical modeling process is avoided by this method, and the real time dynamic simulating function of Simulink would be exerted adequately. This method could be generalized to other complicated control system. This method is adopted to build and analyse the model of humanoid robot. The trajectory tracking and adaptive controller design also proceed based on it. The effect of trajectory tracking is evaluated by fitting-curve theory of least squares method. The anti-interference capability of the robot is improved a lot through comparative analysis.

  7. Modeling and implementation of concurrent logic controllers with use of Petri nets, LSMs, and sequent calculus

    NASA Astrophysics Data System (ADS)

    Tkacz, J.; Bukowiec, A.; Doligalski, M.

    2017-08-01

    The paper presentes the method of modeling and implementation of concurrent controllers. Concurrent controllers are specified by Petri nets. Then Petri nets are decomposed using symbolic deduction method of analysis. Formal methods like sequent calculus system with considered elements of Thelen's algorithm have been used here. As a result, linked state machines (LSMs) are received. Each FSM is implemented using methods of structural decomposition during process of logic synthesis. The method of multiple encoding of microinstruction has been applied. It leads to decreased number of Boolean function realized by combinational part of FSM. The additional decoder could be implemented with the use of memory blocks.

  8. Investigation of multidimensional control systems in the state space and wavelet medium

    NASA Astrophysics Data System (ADS)

    Fedosenkov, D. B.; Simikova, A. A.; Fedosenkov, B. A.

    2018-05-01

    The notions are introduced of “one-dimensional-point” and “multidimensional-point” automatic control systems. To demonstrate the joint use of approaches based on the concepts of state space and wavelet transforms, a method for optimal control in a state space medium represented in the form of time-frequency representations (maps), is considered. The computer-aided control system is formed on the basis of the similarity transformation method, which makes it possible to exclude the use of reduced state variable observers. 1D-material flow signals formed by primary transducers are converted by means of wavelet transformations into multidimensional concentrated-at-a point variables in the form of time-frequency distributions of Cohen’s class. The algorithm for synthesizing a stationary controller for feeding processes is given here. The conclusion is made that the formation of an optimal control law with time-frequency distributions available contributes to the improvement of transient processes quality in feeding subsystems and the mixing unit. Confirming the efficiency of the method presented is illustrated by an example of the current registration of material flows in the multi-feeding unit. The first section in your paper.

  9. Using formal specification in the Guidance and Control Software (GCS) experiment. Formal design and verification technology for life critical systems

    NASA Technical Reports Server (NTRS)

    Weber, Doug; Jamsek, Damir

    1994-01-01

    The goal of this task was to investigate how formal methods could be incorporated into a software engineering process for flight-control systems under DO-178B and to demonstrate that process by developing a formal specification for NASA's Guidance and Controls Software (GCS) Experiment. GCS is software to control the descent of a spacecraft onto a planet's surface. The GCS example is simplified from a real example spacecraft, but exhibits the characteristics of realistic spacecraft control software. The formal specification is written in Larch.

  10. Person Fit Based on Statistical Process Control in an Adaptive Testing Environment. Research Report 98-13.

    ERIC Educational Resources Information Center

    van Krimpen-Stoop, Edith M. L. A.; Meijer, Rob R.

    Person-fit research in the context of paper-and-pencil tests is reviewed, and some specific problems regarding person fit in the context of computerized adaptive testing (CAT) are discussed. Some new methods are proposed to investigate person fit in a CAT environment. These statistics are based on Statistical Process Control (SPC) theory. A…

  11. Controlled Release of Antibiotics from Biodegradable Microcapsules for Wound Infection Control.

    DTIC Science & Technology

    1982-06-18

    evaporation and phase separation methods were used in formulating the microcapsules .(l1) The microencapsulation process will be described in detail in a...intensity to the antibiotic content. Usi.ng both microencapsulation processes, 14C-labeled ampicillin anhydypte microcapsules were synthesized.(12...excellent technical assistance. .. . . g .SETTERSTROM, TICE, LEWIS, and-MEYERS TABLE 1. IN VIVO AMPICILLIN MICROCAPSULES EVALUATED MICROENCAPSULATION

  12. Reducing the layer number of AB stacked multilayer graphene grown on nickel by annealing at low temperature.

    PubMed

    Velasco, J Marquez; Giamini, S A; Kelaidis, N; Tsipas, P; Tsoutsou, D; Kordas, G; Raptis, Y S; Boukos, N; Dimoulas, A

    2015-10-09

    Controlling the number of layers of graphene grown by chemical vapor deposition is crucial for large scale graphene application. We propose here an etching process of graphene which can be applied immediately after growth to control the number of layers. We use nickel (Ni) foil at high temperature (T = 900 °C) to produce multilayer-AB-stacked-graphene (MLG). The etching process is based on annealing the samples in a hydrogen/argon atmosphere at a relatively low temperature (T = 450 °C) inside the growth chamber. The extent of etching is mainly controlled by the annealing process duration. Using Raman spectroscopy we demonstrate that the number of layers was reduced, changing from MLG to few-layer-AB-stacked-graphene and in some cases to randomly oriented few layer graphene near the substrate. Furthermore, our method offers the significant advantage that it does not introduce defects in the samples, maintaining their original high quality. This fact and the low temperature our method uses make it a good candidate for controlling the layer number of already grown graphene in processes with a low thermal budget.

  13. In-line Raman spectroscopic monitoring and feedback control of a continuous twin-screw pharmaceutical powder blending and tableting process.

    PubMed

    Nagy, Brigitta; Farkas, Attila; Gyürkés, Martin; Komaromy-Hiller, Szofia; Démuth, Balázs; Szabó, Bence; Nusser, Dávid; Borbás, Enikő; Marosi, György; Nagy, Zsombor Kristóf

    2017-09-15

    The integration of Process Analytical Technology (PAT) initiative into the continuous production of pharmaceuticals is indispensable for reliable production. The present paper reports the implementation of in-line Raman spectroscopy in a continuous blending and tableting process of a three-component model pharmaceutical system, containing caffeine as model active pharmaceutical ingredient (API), glucose as model excipient and magnesium stearate as lubricant. The real-time analysis of API content, blend homogeneity, and tablet content uniformity was performed using a Partial Least Squares (PLS) quantitative method. The in-line Raman spectroscopic monitoring showed that the continuous blender was capable of producing blends with high homogeneity, and technological malfunctions can be detected by the proposed PAT method. The Raman spectroscopy-based feedback control of the API feeder was also established, creating a 'Process Analytically Controlled Technology' (PACT), which guarantees the required API content in the produced blend. This is, to the best of the authors' knowledge, the first ever application of Raman-spectroscopy in continuous blending and the first Raman-based feedback control in the formulation technology of solid pharmaceuticals. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Methods of controlling hydrogen fluoride pressure during chemical fabrication processes

    DOEpatents

    Solovyov, Vyacheslav [Rocky Point, NY; Wiesmann, Harold [Stony Brook, NY

    2009-11-24

    The present invention is a method for producing a crystalline end-product. The method comprising exposing a fluoride-containing precursor to a hydrogen fluoride absorber under conditions suitable for the conversion of the precursor into the crystalline end-product.

  15. A diagnostic prototype of the potable water subsystem of the Space Station Freedom ECLSS

    NASA Technical Reports Server (NTRS)

    Lukefahr, Brenda D.; Rochowiak, Daniel M.; Benson, Brian L.; Rogers, John S.; Mckee, James W.

    1989-01-01

    In analyzing the baseline Environmental Control and Life Support System (ECLSS) command and control architecture, various processes are found which would be enhanced by the use of knowledge based system methods of implementation. The most suitable process for prototyping using rule based methods are documented, while domain knowledge resources and other practical considerations are examined. Requirements for a prototype rule based software system are documented. These requirements reflect Space Station Freedom ECLSS software and hardware development efforts, and knowledge based system requirements. A quick prototype knowledge based system environment is researched and developed.

  16. Method and apparatus for off-gas composition sensing

    DOEpatents

    Ottesen, David Keith; Allendorf, Sarah Williams; Hubbard, Gary Lee; Rosenberg, David Ezechiel

    1999-01-01

    An apparatus and method for non-intrusive collection of off-gas data in a steelmaking furnace includes structure and steps for transmitting a laser beam through the off-gas produced by a steelmaking furnace, for controlling the transmitting to repeatedly scan the laser beam through a plurality of wavelengths in its tuning range, and for detecting the laser beam transmitted through the off-gas and converting the detected laser beam to an electrical signal. The electrical signal is processed to determine characteristics of the off-gas that are used to analyze and/or control the steelmaking process.

  17. Experimental validation of thermo-chemical algorithm for a simulation of pultrusion processes

    NASA Astrophysics Data System (ADS)

    Barkanov, E.; Akishin, P.; Miazza, N. L.; Galvez, S.; Pantelelis, N.

    2018-04-01

    To provide better understanding of the pultrusion processes without or with temperature control and to support the pultrusion tooling design, an algorithm based on the mixed time integration scheme and nodal control volumes method has been developed. At present study its experimental validation is carried out by the developed cure sensors measuring the electrical resistivity and temperature on the profile surface. By this verification process the set of initial data used for a simulation of the pultrusion process with rod profile has been successfully corrected and finally defined.

  18. Smith predictor with sliding mode control for processes with large dead times

    NASA Astrophysics Data System (ADS)

    Mehta, Utkal; Kaya, İbrahim

    2017-11-01

    The paper discusses the Smith Predictor scheme with Sliding Mode Controller (SP-SMC) for processes with large dead times. This technique gives improved load-disturbance rejection with optimum input control signal variations. A power rate reaching law is incorporated in the sporadic part of sliding mode control such that the overall performance recovers meaningfully. The proposed scheme obtains parameter values by satisfying a new performance index which is based on biobjective constraint. In simulation study, the efficiency of the method is evaluated for robustness and transient performance over reported techniques.

  19. The endpoint detection technique for deep submicrometer plasma etching

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Du, Zhi-yun; Zeng, Yong; Lan, Zhong-went

    2009-07-01

    The availability of reliable optical sensor technology provides opportunities to better characterize and control plasma etching processes in real time, they could play a important role in endpoint detection, fault diagnostics and processes feedback control and so on. The optical emission spectroscopy (OES) method becomes deficient in the case of deep submicrometer gate etching. In the newly developed high density inductively coupled plasma (HD-ICP) etching system, Interferometry endpoint (IEP) is introduced to get the EPD. The IEP fringe count algorithm is investigated to predict the end point, and then its signal is used to control etching rate and to call end point with OES signal in over etching (OE) processes step. The experiment results show that IEP together with OES provide extra process control margin for advanced device with thinner gate oxide.

  20. Optimized method for manufacturing large aspheric surfaces

    NASA Astrophysics Data System (ADS)

    Zhou, Xusheng; Li, Shengyi; Dai, Yifan; Xie, Xuhui

    2007-12-01

    Aspheric optics are being used more and more widely in modern optical systems, due to their ability of correcting aberrations, enhancing image quality, enlarging the field of view and extending the range of effect, while reducing the weight and volume of the system. With optical technology development, we have more pressing requirement to large-aperture and high-precision aspheric surfaces. The original computer controlled optical surfacing (CCOS) technique cannot meet the challenge of precision and machining efficiency. This problem has been thought highly of by researchers. Aiming at the problem of original polishing process, an optimized method for manufacturing large aspheric surfaces is put forward. Subsurface damage (SSD), full aperture errors and full band of frequency errors are all in control of this method. Lesser SSD depth can be gained by using little hardness tool and small abrasive grains in grinding process. For full aperture errors control, edge effects can be controlled by using smaller tools and amendment model with material removal function. For full band of frequency errors control, low frequency errors can be corrected with the optimized material removal function, while medium-high frequency errors by using uniform removing principle. With this optimized method, the accuracy of a K9 glass paraboloid mirror can reach rms 0.055 waves (where a wave is 0.6328μm) in a short time. The results show that the optimized method can guide large aspheric surface manufacturing effectively.

  1. Machine Learning: A Crucial Tool for Sensor Design

    PubMed Central

    Zhao, Weixiang; Bhushan, Abhinav; Santamaria, Anthony D.; Simon, Melinda G.; Davis, Cristina E.

    2009-01-01

    Sensors have been widely used for disease diagnosis, environmental quality monitoring, food quality control, industrial process analysis and control, and other related fields. As a key tool for sensor data analysis, machine learning is becoming a core part of novel sensor design. Dividing a complete machine learning process into three steps: data pre-treatment, feature extraction and dimension reduction, and system modeling, this paper provides a review of the methods that are widely used for each step. For each method, the principles and the key issues that affect modeling results are discussed. After reviewing the potential problems in machine learning processes, this paper gives a summary of current algorithms in this field and provides some feasible directions for future studies. PMID:20191110

  2. Study on robot motion control for intelligent welding processes based on the laser tracking sensor

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Wang, Qian; Tang, Chen; Wang, Ju

    2017-06-01

    A robot motion control method is presented for intelligent welding processes of complex spatial free-form curve seams based on the laser tracking sensor. First, calculate the tip position of the welding torch according to the velocity of the torch and the seam trajectory detected by the sensor. Then, search the optimal pose of the torch under constraints using genetic algorithms. As a result, the intersection point of the weld seam and the laser plane of the sensor is within the detectable range of the sensor. Meanwhile, the angle between the axis of the welding torch and the tangent of the weld seam meets the requirements. The feasibility of the control method is proved by simulation.

  3. A case study: application of statistical process control tool for determining process capability and sigma level.

    PubMed

    Chopra, Vikram; Bairagi, Mukesh; Trivedi, P; Nagar, Mona

    2012-01-01

    Statistical process control is the application of statistical methods to the measurement and analysis of variation process. Various regulatory authorities such as Validation Guidance for Industry (2011), International Conference on Harmonisation ICH Q10 (2009), the Health Canada guidelines (2009), Health Science Authority, Singapore: Guidance for Product Quality Review (2008), and International Organization for Standardization ISO-9000:2005 provide regulatory support for the application of statistical process control for better process control and understanding. In this study risk assessments, normal probability distributions, control charts, and capability charts are employed for selection of critical quality attributes, determination of normal probability distribution, statistical stability, and capability of production processes, respectively. The objective of this study is to determine tablet production process quality in the form of sigma process capability. By interpreting data and graph trends, forecasting of critical quality attributes, sigma process capability, and stability of process were studied. The overall study contributes to an assessment of process at the sigma level with respect to out-of-specification attributes produced. Finally, the study will point to an area where the application of quality improvement and quality risk assessment principles for achievement of six sigma-capable processes is possible. Statistical process control is the most advantageous tool for determination of the quality of any production process. This tool is new for the pharmaceutical tablet production process. In the case of pharmaceutical tablet production processes, the quality control parameters act as quality assessment parameters. Application of risk assessment provides selection of critical quality attributes among quality control parameters. Sequential application of normality distributions, control charts, and capability analyses provides a valid statistical process control study on process. Interpretation of such a study provides information about stability, process variability, changing of trends, and quantification of process ability against defective production. Comparative evaluation of critical quality attributes by Pareto charts provides the least capable and most variable process that is liable for improvement. Statistical process control thus proves to be an important tool for six sigma-capable process development and continuous quality improvement.

  4. Closing the Certification Gaps in Adaptive Flight Control Software

    NASA Technical Reports Server (NTRS)

    Jacklin, Stephen A.

    2008-01-01

    Over the last five decades, extensive research has been performed to design and develop adaptive control systems for aerospace systems and other applications where the capability to change controller behavior at different operating conditions is highly desirable. Although adaptive flight control has been partially implemented through the use of gain-scheduled control, truly adaptive control systems using learning algorithms and on-line system identification methods have not seen commercial deployment. The reason is that the certification process for adaptive flight control software for use in national air space has not yet been decided. The purpose of this paper is to examine the gaps between the state-of-the-art methodologies used to certify conventional (i.e., non-adaptive) flight control system software and what will likely to be needed to satisfy FAA airworthiness requirements. These gaps include the lack of a certification plan or process guide, the need to develop verification and validation tools and methodologies to analyze adaptive controller stability and convergence, as well as the development of metrics to evaluate adaptive controller performance at off-nominal flight conditions. This paper presents the major certification gap areas, a description of the current state of the verification methodologies, and what further research efforts will likely be needed to close the gaps remaining in current certification practices. It is envisioned that closing the gap will require certain advances in simulation methods, comprehensive methods to determine learning algorithm stability and convergence rates, the development of performance metrics for adaptive controllers, the application of formal software assurance methods, the application of on-line software monitoring tools for adaptive controller health assessment, and the development of a certification case for adaptive system safety of flight.

  5. Innovations in coating technology.

    PubMed

    Behzadi, Sharareh S; Toegel, Stefan; Viernstein, Helmut

    2008-01-01

    Despite representing one of the oldest pharmaceutical techniques, coating of dosage forms is still frequently used in pharmaceutical manufacturing. The aims of coating range from simply masking the taste or odour of drugs to the sophisticated controlling of site and rate of drug release. The high expectations for different coating technologies have required great efforts regarding the development of reproducible and controllable production processes. Basically, improvements in coating methods have focused on particle movement, spraying systems, and air and energy transport. Thereby, homogeneous distribution of coating material and increased drying efficiency should be accomplished in order to achieve high end product quality. Moreover, given the claim of the FDA to design the end product quality already during the manufacturing process (Quality by Design), the development of analytical methods for the analysis, management and control of coating processes has attracted special attention during recent years. The present review focuses on recent patents claiming improvements in pharmaceutical coating technology and intends to first familiarize the reader with the available procedures and to subsequently explain the application of different analytical tools. Aiming to structure this comprehensive field, coating technologies are primarily divided into pan and fluidized bed coating methods. Regarding pan coating procedures, pans rotating around inclined, horizontal and vertical axes are reviewed separately. On the other hand, fluidized bed technologies are subdivided into those involving fluidized and spouted beds. Then, continuous processing techniques and improvements in spraying systems are discussed in dedicated chapters. Finally, currently used analytical methods for the understanding and management of coating processes are reviewed in detail in the last section of the review.

  6. A novel eco-friendly technique for efficient control of lime water softening process.

    PubMed

    Ostovar, Mohamad; Amiri, Mohamad

    2013-12-01

    Lime softening is an established type of water treatment used for water softening. The performance of this process is highly dependent on lime dosage. Currently, lime dosage is adjusted manually based on chemical tests, aimed at maintaining the phenolphthalein (P) and total (M) alkalinities within a certain range (2 P - M > or = 5). In this paper, a critical study of the softening process has been presented. It has been shown that the current method is frequently incorrect. Furthermore, electrical conductivity (EC) has been introduced as a novel indicator for effectively characterizing the lime softening process.This novel technique has several advantages over the current alkalinities method. Because no chemical reagents are needed for titration, which is a simple test, there is a considerable reduction in test costs. Additionally, there is a reduction in the treated water hardness and generated sludge during the lime softening process. Therefore, it is highly eco-friendly, and is a very cost effective alternative technique for efficient control of the lime softening process.

  7. Information integration and diagnosis analysis of equipment status and production quality for machining process

    NASA Astrophysics Data System (ADS)

    Zan, Tao; Wang, Min; Hu, Jianzhong

    2010-12-01

    Machining status monitoring technique by multi-sensors can acquire and analyze the machining process information to implement abnormity diagnosis and fault warning. Statistical quality control technique is normally used to distinguish abnormal fluctuations from normal fluctuations through statistical method. In this paper by comparing the advantages and disadvantages of the two methods, the necessity and feasibility of integration and fusion is introduced. Then an approach that integrates multi-sensors status monitoring and statistical process control based on artificial intelligent technique, internet technique and database technique is brought forward. Based on virtual instrument technique the author developed the machining quality assurance system - MoniSysOnline, which has been used to monitoring the grinding machining process. By analyzing the quality data and AE signal information of wheel dressing process the reason of machining quality fluctuation has been obtained. The experiment result indicates that the approach is suitable for the status monitoring and analyzing of machining process.

  8. Computational fluid dynamics modelling of hydraulics and sedimentation in process reactors during aeration tank settling.

    PubMed

    Jensen, M D; Ingildsen, P; Rasmussen, M R; Laursen, J

    2006-01-01

    Aeration tank settling is a control method allowing settling in the process tank during high hydraulic load. The control method is patented. Aeration tank settling has been applied in several waste water treatment plants using the present design of the process tanks. Some process tank designs have shown to be more effective than others. To improve the design of less effective plants, computational fluid dynamics (CFD) modelling of hydraulics and sedimentation has been applied. This paper discusses the results at one particular plant experiencing problems with partly short-circuiting of the inlet and outlet causing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in the process tank. The model has allowed us to establish a clear picture of the problems arising at the plant during aeration tank settling. Secondly, several process tank design changes have been suggested and tested by means of computational fluid dynamics modelling. The most promising design changes have been found and reported.

  9. Microencapsulation and Electrostatic Processing Method

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)

    2000-01-01

    Methods are provided for forming spherical multilamellar microcapsules having alternating hydrophilic and hydrophobic liquid layers, surrounded by flexible, semi-permeable hydrophobic or hydrophilic outer membranes which can be tailored specifically to control the diffusion rate. The methods of the invention rely on low shear mixing and liquid-liquid diffusion process and are particularly well suited for forming microcapsules containing both hydrophilic and hydrophobic drugs. These methods can be carried out in the absence of gravity and do not rely on density-driven phase separation, mechanical mixing or solvent evaporation phases. The methods include the process of forming, washing and filtering microcapsules. In addition, the methods contemplate coating microcapsules with ancillary coatings using an electrostatic field and free fluid electrophoresis of the microcapsules. The microcapsules produced by such methods are particularly useful in the delivery of pharmaceutical compositions.

  10. The physicochemical process of bacterial attachment to abiotic surfaces: Challenges for mechanistic studies, predictability and the development of control strategies.

    PubMed

    Wang, Yi; Lee, Sui Mae; Dykes, Gary

    2015-01-01

    Bacterial attachment to abiotic surfaces can be explained as a physicochemical process. Mechanisms of the process have been widely studied but are not yet well understood due to their complexity. Physicochemical processes can be influenced by various interactions and factors in attachment systems, including, but not limited to, hydrophobic interactions, electrostatic interactions and substratum surface roughness. Mechanistic models and control strategies for bacterial attachment to abiotic surfaces have been established based on the current understanding of the attachment process and the interactions involved. Due to a lack of process control and standardization in the methodologies used to study the mechanisms of bacterial attachment, however, various challenges are apparent in the development of models and control strategies. In this review, the physicochemical mechanisms, interactions and factors affecting the process of bacterial attachment to abiotic surfaces are described. Mechanistic models established based on these parameters are discussed in terms of their limitations. Currently employed methods to study these parameters and bacterial attachment are critically compared. The roles of these parameters in the development of control strategies for bacterial attachment are reviewed, and the challenges that arise in developing mechanistic models and control strategies are assessed.

  11. A real time quality control application for animal production by image processing.

    PubMed

    Sungur, Cemil; Özkan, Halil

    2015-11-01

    Standards of hygiene and health are of major importance in food production, and quality control has become obligatory in this field. Thanks to rapidly developing technologies, it is now possible for automatic and safe quality control of food production. For this purpose, image-processing-based quality control systems used in industrial applications are being employed to analyze the quality of food products. In this study, quality control of chicken (Gallus domesticus) eggs was achieved using a real time image-processing technique. In order to execute the quality control processes, a conveying mechanism was used. Eggs passing on a conveyor belt were continuously photographed in real time by cameras located above the belt. The images obtained were processed by various methods and techniques. Using digital instrumentation, the volume of the eggs was measured, broken/cracked eggs were separated and dirty eggs were determined. In accordance with international standards for classifying the quality of eggs, the class of separated eggs was determined through a fuzzy implication model. According to tests carried out on thousands of eggs, a quality control process with an accuracy of 98% was possible. © 2014 Society of Chemical Industry.

  12. Statistical Design Model (SDM) of satellite thermal control subsystem

    NASA Astrophysics Data System (ADS)

    Mirshams, Mehran; Zabihian, Ehsan; Aarabi Chamalishahi, Mahdi

    2016-07-01

    Satellites thermal control, is a satellite subsystem that its main task is keeping the satellite components at its own survival and activity temperatures. Ability of satellite thermal control plays a key role in satisfying satellite's operational requirements and designing this subsystem is a part of satellite design. In the other hand due to the lack of information provided by companies and designers still doesn't have a specific design process while it is one of the fundamental subsystems. The aim of this paper, is to identify and extract statistical design models of spacecraft thermal control subsystem by using SDM design method. This method analyses statistical data with a particular procedure. To implement SDM method, a complete database is required. Therefore, we first collect spacecraft data and create a database, and then we extract statistical graphs using Microsoft Excel, from which we further extract mathematical models. Inputs parameters of the method are mass, mission, and life time of the satellite. For this purpose at first thermal control subsystem has been introduced and hardware using in the this subsystem and its variants has been investigated. In the next part different statistical models has been mentioned and a brief compare will be between them. Finally, this paper particular statistical model is extracted from collected statistical data. Process of testing the accuracy and verifying the method use a case study. Which by the comparisons between the specifications of thermal control subsystem of a fabricated satellite and the analyses results, the methodology in this paper was proved to be effective. Key Words: Thermal control subsystem design, Statistical design model (SDM), Satellite conceptual design, Thermal hardware

  13. Nano-ceramics and method thereof

    DOEpatents

    Satcher, Jr., Joe H.; Gash, Alex [Livermore, CA; Simpson, Randall [Livermore, CA; Landingham, Richard [Livermore, CA; Reibold, Robert A [Salida, CA

    2006-08-08

    Disclosed herein is a method to produce ceramic materials utilizing the sol-gel process. The methods enable the preparation of intimate homogeneous dispersions of materials while offering the ability to control the size of one component within another. The method also enables the preparation of materials that will densify at reduced temperature.

  14. Optical Fourier diffractometry applied to degraded bone structure recognition

    NASA Astrophysics Data System (ADS)

    Galas, Jacek; Godwod, Krzysztof; Szawdyn, Jacek; Sawicki, Andrzej

    1993-09-01

    Image processing and recognition methods are useful in many fields. This paper presents the hybrid optical and digital method applied to recognition of pathological changes in bones involved by metabolic bone diseases. The trabecular bone structure, registered by x ray on the photographic film, is analyzed in the new type of computer controlled diffractometer. The set of image parameters, extracted from diffractogram, is evaluated by statistical analysis. The synthetic image descriptors in discriminant space, constructed on the base of 3 training groups of images (control, osteoporosis, and osteomalacia groups) by discriminant analysis, allow us to recognize bone samples with degraded bone structure and to recognize the disease. About 89% of the images were classified correctly. This method after optimization process will be verified in medical investigations.

  15. Fault detection of Tennessee Eastman process based on topological features and SVM

    NASA Astrophysics Data System (ADS)

    Zhao, Huiyang; Hu, Yanzhu; Ai, Xinbo; Hu, Yu; Meng, Zhen

    2018-03-01

    Fault detection in industrial process is a popular research topic. Although the distributed control system(DCS) has been introduced to monitor the state of industrial process, it still cannot satisfy all the requirements for fault detection of all the industrial systems. In this paper, we proposed a novel method based on topological features and support vector machine(SVM), for fault detection of industrial process. The proposed method takes global information of measured variables into account by complex network model and predicts whether a system has generated some faults or not by SVM. The proposed method can be divided into four steps, i.e. network construction, network analysis, model training and model testing respectively. Finally, we apply the model to Tennessee Eastman process(TEP). The results show that this method works well and can be a useful supplement for fault detection of industrial process.

  16. Image registration assessment in radiotherapy image guidance based on control chart monitoring.

    PubMed

    Xia, Wenyao; Breen, Stephen L

    2018-04-01

    Image guidance with cone beam computed tomography in radiotherapy can guarantee the precision and accuracy of patient positioning prior to treatment delivery. During the image guidance process, operators need to take great effort to evaluate the image guidance quality before correcting a patient's position. This work proposes an image registration assessment method based on control chart monitoring to reduce the effort taken by the operator. According to the control chart plotted by daily registration scores of each patient, the proposed method can quickly detect both alignment errors and image quality inconsistency. Therefore, the proposed method can provide a clear guideline for the operators to identify unacceptable image quality and unacceptable image registration with minimal effort. Experimental results demonstrate that by using control charts from a clinical database of 10 patients undergoing prostate radiotherapy, the proposed method can quickly identify out-of-control signals and find special cause of out-of-control registration events.

  17. At-line process analytical technology (PAT) for more efficient scale up of biopharmaceutical microfiltration unit operations.

    PubMed

    Watson, Douglas S; Kerchner, Kristi R; Gant, Sean S; Pedersen, Joseph W; Hamburger, James B; Ortigosa, Allison D; Potgieter, Thomas I

    2016-01-01

    Tangential flow microfiltration (MF) is a cost-effective and robust bioprocess separation technique, but successful full scale implementation is hindered by the empirical, trial-and-error nature of scale-up. We present an integrated approach leveraging at-line process analytical technology (PAT) and mass balance based modeling to de-risk MF scale-up. Chromatography-based PAT was employed to improve the consistency of an MF step that had been a bottleneck in the process used to manufacture a therapeutic protein. A 10-min reverse phase ultra high performance liquid chromatography (RP-UPLC) assay was developed to provide at-line monitoring of protein concentration. The method was successfully validated and method performance was comparable to previously validated methods. The PAT tool revealed areas of divergence from a mass balance-based model, highlighting specific opportunities for process improvement. Adjustment of appropriate process controls led to improved operability and significantly increased yield, providing a successful example of PAT deployment in the downstream purification of a therapeutic protein. The general approach presented here should be broadly applicable to reduce risk during scale-up of filtration processes and should be suitable for feed-forward and feed-back process control. © 2015 American Institute of Chemical Engineers.

  18. Strategies for elimination of cyanogens from cassava for reducing toxicity and improving food safety.

    PubMed

    Nambisan, Bala

    2011-03-01

    Toxicity of cassava arises due to the presence of the cyanoglucosides linamarin and lotaustralin which are hydrolysed by endogenous enzyme linamarase to acetonecyanohydrin (ACN) and cyanide (CN) which are toxic. Major research efforts to eliminate/reduce cyanoglucosides have focused on (i) development of acyanogenic cassava varieties by breeding; (ii) controlling its metabolism; and (iii) processing to remove cyanogens. The cyanoglucoside (CNG) content in cassava is genetically controlled and cultivars may be classified as low (<50 μg/g), medium (50-100 μg/g) and high CN (>100 μg CN eq./g) varieties. Molecular techniques for reducing tuber CNG have focused on development of transgenic plants with reduced expression of cyt P 450 in leaves, or increased expression of hydroxynitrilelyase in tuber. For immediate solution, CNG content can be reduced using several processing methods. Traditional methods used for processing include boiling, drying, parboiling and drying, baking, steaming, frying and preparation of flour. These processes result in CN losses ranging from 25% to 98%. The cyanogen level in the final product is influenced both by the tuber CNG and the method of processing. In order to achieve safe levels of 10 μg/g in cassava products, new methods of processing, especially for cassava containing more than 250 μg CN eq./g, remains a challenging problem. Copyright © 2010. Published by Elsevier Ltd.

  19. Digital redesign of anti-wind-up controller for cascaded analog system.

    PubMed

    Chen, Y S; Tsai, J S H; Shieh, L S; Moussighi, M M

    2003-01-01

    The cascaded conventional anti-wind-up (CAW) design method for integral controller is discussed. Then, the prediction-based digital redesign methodology is utilized to find the new pulse amplitude modulated (PAM) digital controller for effective digital control of the analog plant with input saturation constraint. The desired digital controller is determined from existing or pre-designed CAW analog controller. The proposed method provides a novel methodology for indirect digital design of a continuous-time unity output-feedback system with a cascaded analog controller as in the case of PID controllers for industrial control processes with the presence of actuator saturations. It enables us to implement an existing or pre-designed cascaded CAW analog controller via a digital controller effectively.

  20. Thermal Spray Formation of Polymer Coatings

    NASA Technical Reports Server (NTRS)

    Coquill, Scott; Galbraith, Stephen L.; Tuss. Darren L.; Ivosevic, Milan

    2008-01-01

    This innovation forms a sprayable polymer film using powdered precursor materials and an in-process heating method. This device directly applies a powdered polymer onto a substrate to form an adherent, mechanically-sound, and thickness-regulated film. The process can be used to lay down both fully dense and porous, e.g., foam, coatings. This system is field-deployable and includes power distribution, heater controls, polymer constituent material bins, flow controls, material transportation functions, and a thermal spray apparatus. The only thing required for operation in the field is a power source. Because this method does not require solvents, it does not release the toxic, volatile organic compounds of previous methods. Also, the sprayed polymer material is not degraded because this method does not use hot combustion gas or hot plasma gas. This keeps the polymer from becoming rough, porous, or poorly bonded.

  1. Active control of nanolitre droplet contents with convective concentration gradients across permeable walls.

    PubMed

    Zeitoun, Ramsey I; Goudie, Marcus J; Zwier, Jacob; Mahawilli, David; Burns, Mark A

    2011-12-07

    Nanolitre droplets in microfluidic devices can be used to perform thousands of independent chemical and biological experiments while minimizing reagents, cost and time. However, the absence of simple and versatile methods capable of controlling the contents of these nanolitre chemical systems limits their scientific potential. To address this, we have developed a method that is simple to fabricate and can continuously control nanolitre chemical systems by integrating a time-resolved convective flow signal across a permeable membrane wall. With this method, we can independently control the volume and concentration of nanolitre-sized drops without ever directly contacting the fluid. Transport occurring in these systems was also analyzed and thoroughly characterized. We achieved volumetric fluid introduction and removal rates ranging from 0.23 to 4.0 pL s(-1). Furthermore, we expanded this method to perform chemical processes. We precipitated silver chloride using a flow signal of sodium chloride and silver nitrate droplets. From there, we were able to separate sodium chloride reactants with a water flow signal, and dissolve silver chloride solids with an ammonia hydroxide flow signal. Finally, we demonstrate the potential to deliver large molecules and perform physical processes like crystallization and particle packing.

  2. 7 CFR 160.43 - Licensed inspector to be disinterested.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... inspector to be disinterested. No person who determines or controls sales policies or methods of distribution of an eligible processing plant, or the selling prices of the naval stores processed at such plant...

  3. Flood replenishment: a new method of processor control.

    PubMed

    Frank, E D; Gray, J E; Wilken, D A

    1980-01-01

    In mechanized radiographic film processors that process medium to low volumes of film, roll films, and those that process single-emulsion films from nuclear medicine scans, computed tomography, and ultrasound, it is difficult to maintain the developer solution at a stable processing level. We describe our experience using flood replenishment, which is a method in which developer replenisher containing starter solution is introduced in the processor at timed intervals, independent of the number of films being processed. By this process, a stable level of developer activity is maintained in a processor used to develop a medium to low volume of single-emulsion film.

  4. Optimal control of parametric oscillations of compressed flexible bars

    NASA Astrophysics Data System (ADS)

    Alesova, I. M.; Babadzanjanz, L. K.; Pototskaya, I. Yu.; Pupysheva, Yu. Yu.; Saakyan, A. T.

    2018-05-01

    In this paper the problem of damping of the linear systems oscillations with piece-wise constant control is solved. The motion of bar construction is reduced to the form described by Hill's differential equation using the Bubnov-Galerkin method. To calculate switching moments of the one-side control the method of sequential linear programming is used. The elements of the fundamental matrix of the Hill's equation are approximated by trigonometric series. Examples of the optimal control of the systems for various initial conditions and different number of control stages have been calculated. The corresponding phase trajectories and transient processes are represented.

  5. Application of capability indices and control charts in the analytical method control strategy.

    PubMed

    Oliva, Alexis; Llabres Martinez, Matías

    2017-08-01

    In this study, we assessed the usefulness of control charts in combination with the process capability indices, C pm and C pk , in the control strategy of an analytical method. The traditional X-chart and moving range chart were used to monitor the analytical method over a 2-year period. The results confirmed that the analytical method is in-control and stable. Different criteria were used to establish the specifications limits (i.e. analyst requirements) for fixed method performance (i.e. method requirements). If the specification limits and control limits are equal in breadth, the method can be considered "capable" (C pm  = 1), but it does not satisfy the minimum method capability requirements proposed by Pearn and Shu (2003). Similar results were obtained using the C pk index. The method capability was also assessed as a function of method performance for fixed analyst requirements. The results indicate that the method does not meet the requirements of the analytical target approach. A real-example data of a SEC with light-scattering detection method was used as a model whereas previously published data were used to illustrate the applicability of the proposed approach. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Scheduling algorithms for automatic control systems for technological processes

    NASA Astrophysics Data System (ADS)

    Chernigovskiy, A. S.; Tsarev, R. Yu; Kapulin, D. V.

    2017-01-01

    Wide use of automatic process control systems and the usage of high-performance systems containing a number of computers (processors) give opportunities for creation of high-quality and fast production that increases competitiveness of an enterprise. Exact and fast calculations, control computation, and processing of the big data arrays - all of this requires the high level of productivity and, at the same time, minimum time of data handling and result receiving. In order to reach the best time, it is necessary not only to use computing resources optimally, but also to design and develop the software so that time gain will be maximal. For this purpose task (jobs or operations), scheduling techniques for the multi-machine/multiprocessor systems are applied. Some of basic task scheduling methods for the multi-machine process control systems are considered in this paper, their advantages and disadvantages come to light, and also some usage considerations, in case of the software for automatic process control systems developing, are made.

  7. Development and beyond: Strategy for long-term maintenance of an online laser diffraction particle size method in a spray drying manufacturing process.

    PubMed

    Medendorp, Joseph; Bric, John; Connelly, Greg; Tolton, Kelly; Warman, Martin

    2015-08-10

    The purpose of this manuscript is to present the intended use and long-term maintenance strategy of an online laser diffraction particle size method used for process control in a spray drying process. A Malvern Insitec was used for online particle size measurements and a Malvern Mastersizer was used for offline particle size measurements. The two methods were developed in parallel with the Mastersizer serving as the reference method. Despite extensive method development across a range of particle sizes, the two instruments demonstrated different sensitivities to material and process changes over the product lifecycle. This paper will describe the procedure used to ensure consistent alignment of the two methods, thus allowing for continued use of online real-time laser diffraction as a surrogate for the offline system over the product lifecycle. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Basic principles of a flexible astronomical data processing system in UNIX environment.

    NASA Astrophysics Data System (ADS)

    Verkhodanov, O. V.; Erukhimov, B. L.; Monosov, M. L.; Chernenkov, V. N.; Shergin, V. S.

    Methods of construction of a flexible system for astronomical data processing (FADPS) are described. An example of construction of such a FADPS for continuum radiometer data of the RATAN-600 is presented. The Job Control Language of this system is the Job Control Language of OS UNIX. It is shown that using basic commands of the data processing system (DPS) a user, knowing basic principles of Job in OS UNIX, can create his own mini-DPS. Examples of such mini-DPSs are presented.

  9. Prediction and control of the service-related properties of parts at the technological preparation stage and during the manufacture process

    NASA Astrophysics Data System (ADS)

    Bez'iazychnyi, V. F.

    The paper is concerned with the problem of optimizing the machining of aircraft engine parts in order to satisfy certain requirements for tool wear, machining precision and surface layer characteristics, and hardening depth. A generalized multiple-objective function and its computer implementation are developed which make it possible to optimize the machining process without the use of experimental data. Alternative methods of controlling the machining process are discussed.

  10. The development of control and monitoring system on marine current renewable energy Case study: strait of Toyapakeh - Nusa Penida, Bali

    NASA Astrophysics Data System (ADS)

    Arief, I. S.; Suherman, I. H.; Wardani, A. Y.; Baidowi, A.

    2017-05-01

    Control and monitoring system is a continuous process of securing the asset in the Marine Current Renewable Energy. A control and monitoring system is existed each critical components which is embedded in Failure Mode Effect Analysis (FMEA) method. As the result, the process in this paper developed through a matrix sensor. The matrix correlated to critical components and monitoring system which supported by sensors to conduct decision-making.

  11. 40 CFR 412.2 - General definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... also cites the approved methods of analysis. (d) Process wastewater means water directly or indirectly... facilities; direct contact swimming, washing, or spray cooling of animals; or dust control. Process... process wastewater from the production area is or may be applied. (f) New source is defined at 40 CFR 122...

  12. 40 CFR 412.2 - General definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... also cites the approved methods of analysis. (d) Process wastewater means water directly or indirectly... facilities; direct contact swimming, washing, or spray cooling of animals; or dust control. Process... process wastewater from the production area is or may be applied. (f) New source is defined at 40 CFR 122...

  13. 40 CFR 412.2 - General definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... also cites the approved methods of analysis. (d) Process wastewater means water directly or indirectly... facilities; direct contact swimming, washing, or spray cooling of animals; or dust control. Process... process wastewater from the production area is or may be applied. (f) New source is defined at 40 CFR 122...

  14. Desert Talons: Historical Perspectives and Implications of Air Policing in the Middle East

    DTIC Science & Technology

    2009-04-01

    predominant role in support of a smaller ground force has historical precedent. During the 1920s, the Royal Air Forces (RAF) air control method adhered...the Royal Air Force’s (RAF) air control method adhered to the concepts of the inverted blockade, minimum force, precision targeting, and force...owing to its process of rapid communications, Air Methods are, in short, the reverse of the old punitive column. Our policy is one of prevention

  15. System and method for air temperature control in an oxygen transport membrane based reactor

    DOEpatents

    Kelly, Sean M

    2016-09-27

    A system and method for air temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  16. System and method for temperature control in an oxygen transport membrane based reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kelly, Sean M.

    A system and method for temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  17. Growth Control and Disease Mechanisms in Computational Embryogeny

    NASA Technical Reports Server (NTRS)

    Shapiro, Andrew A.; Yogev, Or; Antonsson, Erik K.

    2008-01-01

    This paper presents novel approach to applying growth control and diseases mechanisms in computational embryogeny. Our method, which mimics fundamental processes from biology, enables individuals to reach maturity in a controlled process through a stochastic environment. Three different mechanisms were implemented; disease mechanisms, gene suppression, and thermodynamic balancing. This approach was integrated as part of a structural evolutionary model. The model evolved continuum 3-D structures which support an external load. By using these mechanisms we were able to evolve individuals that reached a fixed size limit through the growth process. The growth process was an integral part of the complete development process. The size of the individuals was determined purely by the evolutionary process where different individuals matured to different sizes. Individuals which evolved with these characteristics have been found to be very robust for supporting a wide range of external loads.

  18. Use of beam deflection to control an electron beam wire deposition process

    NASA Technical Reports Server (NTRS)

    Taminger, Karen M. (Inventor); Hofmeister, William H. (Inventor); Hafley, Robert A. (Inventor)

    2013-01-01

    A method for controlling an electron beam process wherein a wire is melted and deposited on a substrate as a molten pool comprises generating the electron beam with a complex raster pattern, and directing the beam onto an outer surface of the wire to thereby control a location of the wire with respect to the molten pool. Directing the beam selectively heats the outer surface of the wire and maintains the position of the wire with respect to the molten pool. An apparatus for controlling an electron beam process includes a beam gun adapted for generating the electron beam, and a controller adapted for providing the electron beam with a complex raster pattern and for directing the electron beam onto an outer surface of the wire to control a location of the wire with respect to the molten pool.

  19. Contribution au developpement d'une methode de controle des procedes dans une usine de bouletage

    NASA Astrophysics Data System (ADS)

    Gosselin, Claude

    This thesis, a collaborative effort between Ecole de technologie superieure and ArcelorMittal Company, presents the development of a methodology for monitoring and quality control of multivariable industrial production processes. This innovation research mandate was developed at ArcelorMittal Exploitation Miniere (AMEM) pellet plant in Port-Cartier (Quebec, Canada). With this undertaking, ArcelorMittal is striving to maintain its world class level of excellence and continues to pursue initiatives that can augment its competitive advantage worldwide. The plant's gravimetric classification process was retained as a prototype and development laboratory due to its effect on the company's competitiveness and its impact on subsequent steps leading to final production of iron oxide pellets. Concretely, the development of this expertise in process control and in situ monitoring will establish a firm basic knowledge in the fields of complex system physical modeling, data reconciliation, statistical observers, multivariate command and quality control using real-time monitoring of the desirability function. The hydraulic classifier is mathematically modeled. Using planned disturbances on the production line, an identification procedure was established to provide empirical estimations of the model's structural parameters. A new sampling campaign and a previously unpublished data collection and consolidation policy were implemented plant-wide. Access to these invaluable data sources has enabled the establishment of new thresholds that govern the production process and its control. Finally, as a substitute for the traditional quality control process, we have implemented a new strategy based on the use of the desirability function. Our innovation is not in using this Finally, as a substitute for the traditional quality control process, we have implemented a new strategy based on the use of the desirability function. Our innovation is not in using this function as an indicator of overall (economic) satisfaction in the production process, but rather in proposing it as an "observer" of the system's state. The first implementation steps have already demonstrated the method's feasibility as well as other numerous industrial impacts on production processes within the company. Namely, the emergence of the economical aspect as a strategic variable that assures better governance of production processes where quality variables present strategic issues.

  20. Real-Time Optimal Flood Control Decision Making and Risk Propagation Under Multiple Uncertainties

    NASA Astrophysics Data System (ADS)

    Zhu, Feilin; Zhong, Ping-An; Sun, Yimeng; Yeh, William W.-G.

    2017-12-01

    Multiple uncertainties exist in the optimal flood control decision-making process, presenting risks involving flood control decisions. This paper defines the main steps in optimal flood control decision making that constitute the Forecast-Optimization-Decision Making (FODM) chain. We propose a framework for supporting optimal flood control decision making under multiple uncertainties and evaluate risk propagation along the FODM chain from a holistic perspective. To deal with uncertainties, we employ stochastic models at each link of the FODM chain. We generate synthetic ensemble flood forecasts via the martingale model of forecast evolution. We then establish a multiobjective stochastic programming with recourse model for optimal flood control operation. The Pareto front under uncertainty is derived via the constraint method coupled with a two-step process. We propose a novel SMAA-TOPSIS model for stochastic multicriteria decision making. Then we propose the risk assessment model, the risk of decision-making errors and rank uncertainty degree to quantify the risk propagation process along the FODM chain. We conduct numerical experiments to investigate the effects of flood forecast uncertainty on optimal flood control decision making and risk propagation. We apply the proposed methodology to a flood control system in the Daduhe River basin in China. The results indicate that the proposed method can provide valuable risk information in each link of the FODM chain and enable risk-informed decisions with higher reliability.

  1. A Numerical Optimization Approach for Tuning Fuzzy Logic Controllers

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Garg, Devendra P.

    1998-01-01

    This paper develops a method to tune fuzzy controllers using numerical optimization. The main attribute of this approach is that it allows fuzzy logic controllers to be tuned to achieve global performance requirements. Furthermore, this approach allows design constraints to be implemented during the tuning process. The method tunes the controller by parameterizing the membership functions for error, change-in-error and control output. The resulting parameters form a design vector which is iteratively changed to minimize an objective function. The minimal objective function results in an optimal performance of the system. A spacecraft mounted science instrument line-of-sight pointing control is used to demonstrate results.

  2. Using the scanning electron microscope on the production line to assure quality semiconductors

    NASA Technical Reports Server (NTRS)

    Adolphsen, J. W.; Anstead, R. J.

    1972-01-01

    The use of the scanning electron microscope to detect metallization defects introduced during batch processing of semiconductor devices is discussed. A method of determining metallization integrity was developed which culminates in a procurement specification using the scanning microscope on the production line as a quality control tool. Batch process control of the metallization operation is monitored early in the manufacturing cycle.

  3. Processing of non-oxide ceramics from sol-gel methods

    DOEpatents

    Landingham, Richard; Reibold, Robert A.; Satcher, Joe

    2014-12-12

    A general procedure applied to a variety of sol-gel precursors and solvent systems for preparing and controlling homogeneous dispersions of very small particles within each other. Fine homogenous dispersions processed at elevated temperatures and controlled atmospheres make a ceramic powder to be consolidated into a component by standard commercial means: sinter, hot press, hot isostatic pressing (HIP), hot/cold extrusion, spark plasma sinter (SPS), etc.

  4. Optimising UAV topographic surveys processed with structure-from-motion: Ground control quality, quantity and bundle adjustment

    NASA Astrophysics Data System (ADS)

    James, Mike R.; Robson, Stuart; d'Oleire-Oltmanns, Sebastian; Niethammer, Uwe

    2016-04-01

    Structure-from-motion (SfM) algorithms are greatly facilitating the production of detailed topographic models based on images collected by unmanned aerial vehicles (UAVs). However, SfM-based software does not generally provide the rigorous photogrammetric analysis required to fully understand survey quality. Consequently, error related to problems in control point data or the distribution of control points can remain undiscovered. Even if these errors are not large in magnitude, they can be systematic, and thus have strong implications for the use of products such as digital elevation models (DEMs) and orthophotos. Here, we develop a Monte Carlo approach to (1) improve the accuracy of products when SfM-based processing is used and (2) reduce the associated field effort by identifying suitable lower density deployments of ground control points. The method highlights over-parameterisation during camera self-calibration and provides enhanced insight into control point performance when rigorous error metrics are not available. Processing was implemented using commonly-used SfM-based software (Agisoft PhotoScan), which we augment with semi-automated and automated GCPs image measurement. We apply the Monte Carlo method to two contrasting case studies - an erosion gully survey (Taurodont, Morocco) carried out with an fixed-wing UAV, and an active landslide survey (Super-Sauze, France), acquired using a manually controlled quadcopter. The results highlight the differences in the control requirements for the two sites, and we explore the implications for future surveys. We illustrate DEM sensitivity to critical processing parameters and show how the use of appropriate parameter values increases DEM repeatability and reduces the spatial variability of error due to processing artefacts.

  5. Part height control of laser metal additive manufacturing process

    NASA Astrophysics Data System (ADS)

    Pan, Yu-Herng

    Laser Metal Deposition (LMD) has been used to not only make but also repair damaged parts in a layer-by-layer fashion. Parts made in this manner may produce less waste than those made through conventional machining processes. However, a common issue of LMD involves controlling the deposition's layer thickness. Accuracy is important, and as it increases, both the time required to produce the part and the material wasted during the material removal process (e.g., milling, lathe) decrease. The deposition rate is affected by multiple parameters, such as the powder feed rate, laser input power, axis feed rate, material type, and part design, the values of each of which may change during the LMD process. Using a mathematical model to build a generic equation that predicts the deposition's layer thickness is difficult due to these complex parameters. In this thesis, we propose a simple method that utilizes a single device. This device uses a pyrometer to monitor the current build height, thereby allowing the layer thickness to be controlled during the LMD process. This method also helps the LMD system to build parts even with complex parameters and to increase material efficiency.

  6. Formulation and dissolution kinetics study of hydrophilic matrix tablets with tramadol hydrochloride and different co-processed dry binders.

    PubMed

    Komersová, Alena; Lochař, Václav; Myslíková, Kateřina; Mužíková, Jitka; Bartoš, Martin

    2016-12-01

    The aim of this study is to present the possibility of using of co-processed dry binders for formulation of matrix tablets with drug controlled release. Hydrophilic matrix tablets with tramadol hydrochloride, hypromellose and different co-processed dry binders were prepared by direct compression method. Hypromelloses Methocel™ K4M Premium CR or Methocel™ K100M Premium CR were used as controlled release agents and Prosolv® SMCC 90 or Disintequik™ MCC 25 were used as co-processed dry binders. Homogeneity of the tablets was evaluated using scanning electron microscopy and energy dispersive X-ray microanalysis. The release of tramadol hydrochloride from prepared formulations was studied by dissolution test method. The dissolution profiles obtained were evaluated by non-linear regression analysis, release rate constants and other kinetic parameters were determined. It was found that matrix tablets based on Prosolv® SMCC 90 and Methocel™ Premium CR cannot control the tramadol release effectively for >12h and tablets containing Disintequik™ MCC 25 and Methocel™ Premium CR >8h. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Method and apparatus for improved wire saw slurry

    DOEpatents

    Costantini, Michael A.; Talbott, Jonathan A.; Chandra, Mohan; Prasad, Vishwanath; Caster, Allison; Gupta, Kedar P.; Leyvraz, Philippe

    2000-09-05

    A slurry recycle process for use in free-abrasive machining operations such as for wire saws used in wafer slicing of ingots, where the used slurry is separated into kerf-rich and abrasive-rich components, and the abrasive-rich component is reconstituted into a makeup slurry. During the process, the average particle size of the makeup slurry is controlled by monitoring the condition of the kerf and abrasive components and making necessary adjustments to the separating force and dwell time of the separator apparatus. Related pre-separator and post separator treatments, and feedback of one or the other separator slurry output components for mixing with incoming used slurry and recirculation through the separator, provide further effectiveness and additional control points in the process. The kerf-rich component is eventually or continually removed; the abrasive-rich component is reconstituted into a makeup slurry with a controlled, average particle size such that the products of the free-abrasive machining method using the recycled slurry process of the invention are of consistent high quality with less TTV deviation from cycle to cycle for a prolonged period or series of machining operations.

  8. Method for enhanced control of welding processes

    DOEpatents

    Sheaffer, Donald A.; Renzi, Ronald F.; Tung, David M.; Schroder, Kevin

    2000-01-01

    Method and system for producing high quality welds in welding processes, in general, and gas tungsten arc (GTA) welding, in particular by controlling weld penetration. Light emitted from a weld pool is collected from the backside of a workpiece by optical means during welding and transmitted to a digital video camera for further processing, after the emitted light is first passed through a short wavelength pass filter to remove infrared radiation. By filtering out the infrared component of the light emitted from the backside weld pool image, the present invention provides for the accurate determination of the weld pool boundary. Data from the digital camera is fed to an imaging board which focuses on a 100.times.100 pixel portion of the image. The board performs a thresholding operation and provides this information to a digital signal processor to compute the backside weld pool dimensions and area. This information is used by a control system, in a dynamic feedback mode, to automatically adjust appropriate parameters of a welding system, such as the welding current, to control weld penetration and thus, create a uniform weld bead and high quality weld.

  9. Some Inspection Methods for Quality Control and In-service Inspection of GLARE

    NASA Astrophysics Data System (ADS)

    Sinke, J.

    2003-07-01

    Quality control of materials and structures is an important issue, also for GLARE. During the manufacturing stage the processes and materials should be monitored and checked frequently in order to obtain a qualified product. During the operation of the aircraft, frequent monitoring and inspections are performed to maintain the quality at a prescribed level. Therefore, in-service inspection methods are applied, and when necessary repair activities are conducted. For the quality control of the GLARE panels and components during manufacturing, the C-scan method proves to be an effective tool. For in-service inspection the Eddy Current Method is one of the suitable options. In this paper a brief overview is presented of both methods and their application on GLARE products.

  10. Software development environments: Status and trends

    NASA Technical Reports Server (NTRS)

    Duffel, Larry E.

    1988-01-01

    Currently software engineers are the essential integrating factors tying several components together. The components consist of process, methods, computers, tools, support environments, and software engineers. The engineers today empower the tools versus the tools empowering the engineers. Some of the issues in software engineering are quality, managing the software engineering process, and productivity. A strategy to accomplish this is to promote the evolution of software engineering from an ad hoc, labor intensive activity to a managed, technology supported discipline. This strategy may be implemented by putting the process under management control, adopting appropriate methods, inserting the technology that provides automated support for the process and methods, collecting automated tools into an integrated environment and educating the personnel.

  11. Head-target tracking control of well drilling

    NASA Astrophysics Data System (ADS)

    Agzamov, Z. V.

    2018-05-01

    The method of directional drilling trajectory control for oil and gas wells using predictive models is considered in the paper. The developed method does not apply optimization and therefore there is no need for the high-performance computing. Nevertheless, it allows following the well-plan with high precision taking into account process input saturation. Controller output is calculated both from the present target reference point of the well-plan and from well trajectory prediction with using the analytical model. This method allows following a well-plan not only on angular, but also on the Cartesian coordinates. Simulation of the control system has confirmed the high precision and operation performance with a wide range of random disturbance action.

  12. Acoustic processing method for MS/MS experiments

    NASA Technical Reports Server (NTRS)

    Whymark, R. R.

    1973-01-01

    Acoustical methods in which intense sound beams can be used to control the position of objects are considered. The position control arises from the radiation force experienced when a body is placed in a sound field. A description of the special properties of intense sound fields useful for position control is followed by a discussion of the more obvious methods of position, namely the use of multiple sound beams. A new type of acoustic position control device is reported that has advantages of simplicity and reliability and utilizes only a single sound beam. Finally a description is given of an experimental single beam levitator, and the results obtained in a number of key levitation experiments.

  13. A unified method for evaluating real-time computer controllers: A case study. [aircraft control

    NASA Technical Reports Server (NTRS)

    Shin, K. G.; Krishna, C. M.; Lee, Y. H.

    1982-01-01

    A real time control system consists of a synergistic pair, that is, a controlled process and a controller computer. Performance measures for real time controller computers are defined on the basis of the nature of this synergistic pair. A case study of a typical critical controlled process is presented in the context of new performance measures that express the performance of both controlled processes and real time controllers (taken as a unit) on the basis of a single variable: controller response time. Controller response time is a function of current system state, system failure rate, electrical and/or magnetic interference, etc., and is therefore a random variable. Control overhead is expressed as a monotonically nondecreasing function of the response time and the system suffers catastrophic failure, or dynamic failure, if the response time for a control task exceeds the corresponding system hard deadline, if any. A rigorous probabilistic approach is used to estimate the performance measures. The controlled process chosen for study is an aircraft in the final stages of descent, just prior to landing. First, the performance measures for the controller are presented. Secondly, control algorithms for solving the landing problem are discussed and finally the impact of the performance measures on the problem is analyzed.

  14. An integrated algorithm for hypersonic fluid-thermal-structural numerical simulation

    NASA Astrophysics Data System (ADS)

    Li, Jia-Wei; Wang, Jiang-Feng

    2018-05-01

    In this paper, a fluid-structural-thermal integrated method is presented based on finite volume method. A unified integral equations system is developed as the control equations for physical process of aero-heating and structural heat transfer. The whole physical field is discretized by using an up-wind finite volume method. To demonstrate its capability, the numerical simulation of Mach 6.47 flow over stainless steel cylinder shows a good agreement with measured values, and this method dynamically simulates the objective physical processes. Thus, the integrated algorithm proves to be efficient and reliable.

  15. 3D measurement by digital photogrammetry

    NASA Astrophysics Data System (ADS)

    Schneider, Carl T.

    1993-12-01

    Photogrammetry is well known in geodetic surveys as aerial photogrammetry or close range applications as architectural photogrammetry. The photogrammetric methods and algorithms combined with digital cameras and digital image processing methods are now introduced for industrial applications as automation and quality control. The presented paper will describe the photogrammetric and digital image processing algorithms and the calibration methods. These algorithms and methods were demonstrated with application examples. These applications are a digital photogrammetric workstation as a mobil multi purpose 3D measuring tool and a tube measuring system as an example for a single purpose tool.

  16. EMC analysis of MOS-1

    NASA Astrophysics Data System (ADS)

    Ishizawa, Y.; Abe, K.; Shirako, G.; Takai, T.; Kato, H.

    The electromagnetic compatibility (EMC) control method, system EMC analysis method, and system test method which have been applied to test the components of the MOS-1 satellite are described. The merits and demerits of the problem solving, specification, and system approaches to EMC control are summarized, and the data requirements of the SEMCAP (specification and electromagnetic compatibility analysis program) computer program for verifying the EMI safety margin of the components are sumamrized. Examples of EMC design are mentioned, and the EMC design process and selection method for EMC critical points are shown along with sample EMC test results.

  17. Active chatter suppression with displacement-only measurement in turning process

    NASA Astrophysics Data System (ADS)

    Ma, Haifeng; Wu, Jianhua; Yang, Liuqing; Xiong, Zhenhua

    2017-08-01

    Regenerative chatter is a major hindrance for achieving high quality and high production rate in machining processes. Various active controllers have been proposed to mitigate chatter. However, most of existing controllers were developed on the basis of multi-states feedback of the system and state observers were usually needed. Moreover, model parameters of the machining process (mass, damping and stiffness) were required in existing active controllers. In this study, an active sliding mode controller, which employs a dynamic output feedback sliding surface for the unmatched condition and an adaptive law for disturbance estimation, is designed, analyzed, and validated for chatter suppression in turning process. Only displacement measurement is required by this approach. Other sensors and state observers are not needed. Moreover, it facilitates a rapid implementation since the designed controller is established without using model parameters of the turning process. Theoretical analysis, numerical simulations and experiments on a computer numerical control (CNC) lathe are presented. It shows that the chatter can be substantially attenuated and the chatter-free region can be significantly expanded with the presented method.

  18. A Flexible Self-Paced Course in Process Control.

    ERIC Educational Resources Information Center

    King, Franklin G.

    1979-01-01

    Describes an undergraduate chemical engineering course which has been taught by a self-paced instructional method at Howard University, Washington, D.C. The instructional method, course description, and students' grades are also discussed. (HM)

  19. An Optimized Trajectory Planning for Welding Robot

    NASA Astrophysics Data System (ADS)

    Chen, Zhilong; Wang, Jun; Li, Shuting; Ren, Jun; Wang, Quan; Cheng, Qunchao; Li, Wentao

    2018-03-01

    In order to improve the welding efficiency and quality, this paper studies the combined planning between welding parameters and space trajectory for welding robot and proposes a trajectory planning method with high real-time performance, strong controllability and small welding error. By adding the virtual joint at the end-effector, the appropriate virtual joint model is established and the welding process parameters are represented by the virtual joint variables. The trajectory planning is carried out in the robot joint space, which makes the control of the welding process parameters more intuitive and convenient. By using the virtual joint model combined with the B-spline curve affine invariant, the welding process parameters are indirectly controlled by controlling the motion curve of the real joint. To solve the optimal time solution as the goal, the welding process parameters and joint space trajectory joint planning are optimized.

  20. Analytical design of an industrial two-term controller for optimal regulatory control of open-loop unstable processes under operational constraints.

    PubMed

    Tchamna, Rodrigue; Lee, Moonyong

    2018-01-01

    This paper proposes a novel optimization-based approach for the design of an industrial two-term proportional-integral (PI) controller for the optimal regulatory control of unstable processes subjected to three common operational constraints related to the process variable, manipulated variable and its rate of change. To derive analytical design relations, the constrained optimal control problem in the time domain was transformed into an unconstrained optimization problem in a new parameter space via an effective parameterization. The resulting optimal PI controller has been verified to yield optimal performance and stability of an open-loop unstable first-order process under operational constraints. The proposed analytical design method explicitly takes into account the operational constraints in the controller design stage and also provides useful insights into the optimal controller design. Practical procedures for designing optimal PI parameters and a feasible constraint set exclusive of complex optimization steps are also proposed. The proposed controller was compared with several other PI controllers to illustrate its performance. The robustness of the proposed controller against plant-model mismatch has also been investigated. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  1. 9 CFR 320.1 - Records required to be kept.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... processing procedures to destroy trichinae in § 318.10(c)(3)(iv) (Methods 5 and 6). (8) Records of nutrition... control of the production process using advanced meat/bone separation machinery and meat recovery systems...

  2. Optimal control of the gear shifting process for shift smoothness in dual-clutch transmissions

    NASA Astrophysics Data System (ADS)

    Li, Guoqiang; Görges, Daniel

    2018-03-01

    The control of the transmission system in vehicles is significant for the driving comfort. In order to design a controller for smooth shifting and comfortable driving, a dynamic model of a dual-clutch transmission is presented in this paper. A finite-time linear quadratic regulator is proposed for the optimal control of the two friction clutches in the torque phase for the upshift process. An integral linear quadratic regulator is introduced to regulate the relative speed difference between the engine and the slipping clutch under the optimization of the input torque during the inertia phase. The control objective focuses on smoothing the upshift process so as to improve the driving comfort. Considering the available sensors in vehicles for feedback control, an observer design is presented to track the immeasurable variables. Simulation results show that the jerk can be reduced both in the torque phase and inertia phase, indicating good shift performance. Furthermore, compared with conventional controllers for the upshift process, the proposed control method can reduce shift jerk and improve shift quality.

  3. EOS mapping accuracy study

    NASA Technical Reports Server (NTRS)

    Forrest, R. B.; Eppes, T. A.; Ouellette, R. J.

    1973-01-01

    Studies were performed to evaluate various image positioning methods for possible use in the earth observatory satellite (EOS) program and other earth resource imaging satellite programs. The primary goal is the generation of geometrically corrected and registered images, positioned with respect to the earth's surface. The EOS sensors which were considered were the thematic mapper, the return beam vidicon camera, and the high resolution pointable imager. The image positioning methods evaluated consisted of various combinations of satellite data and ground control points. It was concluded that EOS attitude control system design must be considered as a part of the image positioning problem for EOS, along with image sensor design and ground image processing system design. Study results show that, with suitable efficiency for ground control point selection and matching activities during data processing, extensive reliance should be placed on use of ground control points for positioning the images obtained from EOS and similar programs.

  4. Economics of electron beam and electrical discharge processing for post-combustion NO(x) control in internal combustion engines

    NASA Astrophysics Data System (ADS)

    Penetrante, B. M.

    1993-08-01

    The physics and chemistry of non-thermal plasma processing for post-combustion NO(x) control in internal combustion engines are discussed. A comparison of electron beam and electrical discharge processing is made regarding their power consumption, radical production, NO(x) removal mechanisms, and by-product formation. Pollution control applications present a good opportunity for transferring pulsed power techniques to the commercial sector. However, unless advances are made to drastically reduce the price and power consumption of electron beam sources and pulsed power systems, these plasma techniques will not become commercially competitive with conventional thermal or surface-catalytic methods.

  5. Collection of process data after cardiac surgery: initial implementation with a Java-based intranet applet.

    PubMed

    Ratcliffe, M B; Khan, J H; Magee, K M; McElhinney, D B; Hubner, C

    2000-06-01

    Using a Java-based intranet program (applet), we collected postoperative process data after coronary artery bypass grafting. A Java-based applet was developed and deployed on a hospital intranet. Briefly, the nurse entered patient process data using a point and click interface. The applet generated a nursing note, and process data were saved in a Microsoft Access database. In 10 patients, this method was validated by comparison with a retrospective chart review. In 45 consecutive patients, weekly control charts were generated from the data. When aberrations from the pathway occurred, feedback was initiated to restore the goals of the critical pathway. The intranet process data collection method was verified by a manual chart review with 98% sensitivity. The control charts for time to extubation, intensive care unit stay, and hospital stay showed a deviation from critical pathway goals after the first 20 patients. Feedback modulation was associated with a return to critical pathway goals. Java-based applets are inexpensive and can collect accurate postoperative process data, identify critical pathway deviations, and allow timely feedback of process data.

  6. Developing a Three Processes Framework to Analyze Hydrologic Performance of Urban Stormwater Management in a Watershed Scale

    NASA Astrophysics Data System (ADS)

    Lyu, H.; Ni, G.; Sun, T.

    2016-12-01

    Urban stormwater management contributes to recover water cycle to a nearly natural situation. It is a challenge for analyzing the hydrologic performance in a watershed scale, since the measures are various of sorts and scales and work in different processes. A three processes framework is developed to simplify the urban hydrologic process on the surface and evaluate the urban stormwater management. The three processes include source utilization, transfer regulation and terminal detention, by which the stormwater is controlled in order or discharged. Methods for analyzing performance are based on the water controlled proportions by each process, which are calculated using USEPA Stormwater Management Model. A case study form Beijing is used to illustrate how the performance varies under a set of designed events of different return periods. This framework provides a method to assess urban stormwater management as a whole system considering the interaction between measures, and to examine if there is any weak process of an urban watershed to be improved. The results help to make better solutions of urban water crisis.

  7. [Development of whole process quality control and management system of traditional Chinese medicine decoction pieces based on traditional Chinese medicine quality tree].

    PubMed

    Yu, Wen-Kang; Dong, Ling; Pei, Wen-Xuan; Sun, Zhi-Rong; Dai, Jun-Dong; Wang, Yun

    2017-12-01

    The whole process quality control and management of traditional Chinese medicine (TCM) decoction pieces is a system engineering, involving the base environment, seeds and seedlings, harvesting, processing and other multiple steps, so the accurate identification of factors in TCM production process that may induce the quality risk, as well as reasonable quality control measures are very important. At present, the concept of quality risk is mainly concentrated in the aspects of management and regulations, etc. There is no comprehensive analysis on possible risks in the quality control process of TCM decoction pieces, or analysis summary of effective quality control schemes. A whole process quality control and management system for TCM decoction pieces based on TCM quality tree was proposed in this study. This system effectively combined the process analysis method of TCM quality tree with the quality risk management, and can help managers to make real-time decisions while realizing the whole process quality control of TCM. By providing personalized web interface, this system can realize user-oriented information feedback, and was convenient for users to predict, evaluate and control the quality of TCM. In the application process, the whole process quality control and management system of the TCM decoction pieces can identify the related quality factors such as base environment, cultivation and pieces processing, extend and modify the existing scientific workflow according to their own production conditions, and provide different enterprises with their own quality systems, to achieve the personalized service. As a new quality management model, this paper can provide reference for improving the quality of Chinese medicine production and quality standardization. Copyright© by the Chinese Pharmaceutical Association.

  8. Development of process data capturing, analysis and controlling for thermal spray techniques - SprayTracker

    NASA Astrophysics Data System (ADS)

    Kelber, C.; Marke, S.; Trommler, U.; Rupprecht, C.; Weis, S.

    2017-03-01

    Thermal spraying processes are becoming increasingly important in high-technology areas, such as automotive engineering and medical technology. The method offers the advantage of a local layer application with different materials and high deposition rates. Challenges in the application of thermal spraying result from the complex interaction of different influencing variables, which can be attributed to the properties of different materials, operating equipment supply, electrical parameters, flow mechanics, plasma physics and automation. In addition, spraying systems are subject to constant wear. Due to the process specification and the high demands on the produced coatings, innovative quality assurance tools are necessary. A central aspect, which has not yet been considered, is the data management in relation to the present measured variables, in particular the spraying system, the handling system, working safety devices and additional measuring sensors. Both the recording of all process-characterizing variables, their linking and evaluation as well as the use of the data for the active process control presuppose a novel, innovative control system (hardware and software) that was to be developed within the scope of the research project. In addition, new measurement methods and sensors are to be developed and qualified in order to improve the process reliability of thermal spraying.

  9. 76 FR 70833 - National Emission Standards for Hazardous Air Pollutant Emissions for Primary Lead Processing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... Classification System. \\2\\ Maximum Achievable Control Technology. Table 2 is not intended to be exhaustive, but..., methods, systems, or techniques that reduce the volume of or eliminate HAP emissions through process changes, substitution of materials, or other modifications; enclose systems or processes to eliminate...

  10. 40 CFR 420.21 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... control system that utilizes filters to remove iron-bearing particles (fines) from blast furnace or... level is 10 pg/L per EPA Method 1613B for water and wastewater samples. (d) The term pg/L means... pollution control system means an emission control system that utilizes water to clean process or furnace...

  11. 40 CFR 420.21 - Specialized definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... control system that utilizes filters to remove iron-bearing particles (fines) from blast furnace or... level is 10 pg/L per EPA Method 1613B for water and wastewater samples. (d) The term pg/L means... pollution control system means an emission control system that utilizes water to clean process or furnace...

  12. 40 CFR 420.21 - Specialized definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... control system that utilizes filters to remove iron-bearing particles (fines) from blast furnace or... level is 10 pg/L per EPA Method 1613B for water and wastewater samples. (d) The term pg/L means... pollution control system means an emission control system that utilizes water to clean process or furnace...

  13. Command and Control: An Introduction

    DTIC Science & Technology

    1989-03-01

    34 [Ref. 13:p. 31) F. SUMMARY With an understanding of the architecture of generic command and control sytems , it is now time to examine the 146 methods...Center ABM Antiballistic Missile ACCS Army Command and Control System ACE Aviation Combat Element ADP Automatic Data Processing AFB Air Force Base AFM Air

  14. A New Approach to Flood Protection Design and Riparian Management

    Treesearch

    Philip B. Williams; Mitchell L. Swanson

    1989-01-01

    Conventional engineering methods of flood control design focus narrowly on the efficient conveyance of water, with little regard for environmental resource planning and natural geomorphic processes. Consequently, flood control projects are often environmentally disastrous, expensive to maintain, and even inadequate to control floods. In addition, maintenance programs...

  15. Metal-Ceramic composites via “in situ” methods

    NASA Astrophysics Data System (ADS)

    Florea, R. M.

    2017-08-01

    Several “in situ” methods for obtaining composite materials with ceramic particles were developed in order to overcome some of the inherent problems associated with conventional processes. This paper reviews the obtaining processes of composite materials with a greater emphasis on nitriding and oxidation by directed melting. These obtaining methods provide microstructures with different combinations of metal-ceramic. Metal matrix composites with controlled amounts of dispersed ceramic particles are obtained by “in situ” processes. The composite materials obtained are having different properties by controlling various processing variables such as temperature, time, the reactant phases and the reinforcing material. The properties of the “in situ” obtained materials depend mainly on the matrix and volume fraction of constituent phase. Briefly are reviewed the mechanical properties, hardness mechanisms and possible applications of these composite materials. Nitridation is much more attractive because with the variation of process parameters is obtained a wider range of microstructures and properties. The activation energy for the formation of AlN (A1N ˜ 100 kJ/mole) is smaller than that of oxidation (Al2O3 ˜ 400 kJ/mole) and growth rates (3 × 10-2 gm/cm2/s) are at least three times higher for oxidation.

  16. SPECIAL ISSUE ON OPTICAL PROCESSING OF INFORMATION: Information transmission systems based on two-mode lasers with controlled emission frequencies

    NASA Astrophysics Data System (ADS)

    Naumov, N. V.; Petrovskii, V. N.; Protsenko, E. D.; Shananin, R. A.

    1995-10-01

    Various information transmission systems, based on two-mode lasers with controlled emission frequencies, are proposed. It is suggested that these systems can be implemented by modulation of the intermode spacing of a two-mode laser. An experimental investigation is reported of frequency control methods. It is shown that these methods should make it possible to construct information transmission systems with high transmission rates subject to weak nonlinear distortions of the information-carrying signal.

  17. Techniques for improving transients in learning control systems

    NASA Technical Reports Server (NTRS)

    Chang, C.-K.; Longman, Richard W.; Phan, Minh

    1992-01-01

    A discrete modern control formulation is used to study the nature of the transient behavior of the learning process during repetitions. Several alternative learning control schemes are developed to improve the transient performance. These include a new method using an alternating sign on the learning gain, which is very effective in limiting peak transients and also very useful in multiple-input, multiple-output systems. Other methods include learning at an increasing number of points progressing with time, or an increasing number of points of increasing density.

  18. Optimization of PID Parameters Utilizing Variable Weight Grey-Taguchi Method and Particle Swarm Optimization

    NASA Astrophysics Data System (ADS)

    Azmi, Nur Iffah Mohamed; Arifin Mat Piah, Kamal; Yusoff, Wan Azhar Wan; Romlay, Fadhlur Rahman Mohd

    2018-03-01

    Controller that uses PID parameters requires a good tuning method in order to improve the control system performance. Tuning PID control method is divided into two namely the classical methods and the methods of artificial intelligence. Particle swarm optimization algorithm (PSO) is one of the artificial intelligence methods. Previously, researchers had integrated PSO algorithms in the PID parameter tuning process. This research aims to improve the PSO-PID tuning algorithms by integrating the tuning process with the Variable Weight Grey- Taguchi Design of Experiment (DOE) method. This is done by conducting the DOE on the two PSO optimizing parameters: the particle velocity limit and the weight distribution factor. Computer simulations and physical experiments were conducted by using the proposed PSO- PID with the Variable Weight Grey-Taguchi DOE and the classical Ziegler-Nichols methods. They are implemented on the hydraulic positioning system. Simulation results show that the proposed PSO-PID with the Variable Weight Grey-Taguchi DOE has reduced the rise time by 48.13% and settling time by 48.57% compared to the Ziegler-Nichols method. Furthermore, the physical experiment results also show that the proposed PSO-PID with the Variable Weight Grey-Taguchi DOE tuning method responds better than Ziegler-Nichols tuning. In conclusion, this research has improved the PSO-PID parameter by applying the PSO-PID algorithm together with the Variable Weight Grey-Taguchi DOE method as a tuning method in the hydraulic positioning system.

  19. Study on the simultaneous determination of seven benzoylurea pesticides in Oolong tea and their leaching characteristics during infusing process by HPLC-MS/MS.

    PubMed

    Chen, Lei; Chen, JinFa; Guo, Ying; Li, JianRong; Yang, YiQiang; Xu, LiangJun; Fu, FengFu

    2014-01-15

    A method for the simultaneous determination of 7 benzoylurea pesticides (chlorfluazuron, diflubenzuron, fluazuron, flufenoxuron, hexaflumuron, teflubenzuron and triflumuron) in the manufactured Oolong tea leaves and its infusion was described. The method has a LOD of 0.03-1.00ng/mL, a recovery of 90.4-103% for made tea and 90.3-102% for tea-infused liquid, respectively. By using the proposed method, the leaching characteristics of above 7 pesticides during infusing process were investigated. The experimental results revealed that: (1) diflubenzuron can be most easily extracted out during infusing process, followed by triflumuron, teflubenzuron, hexaflumuron, chlorfluazuron, flufenoxuron and fluazuron. (2) The leaching of flufenoxuron and chlorfluazuron during infusing process seems to be controlled by only their solubility, whereas, the leaching of other 5 benzoylurea insecticides was primarily controlled by their partitioning coefficient between made tea and hot water. The results of this study are helpful for the accurate evaluation of the safety of Oolong tea. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Shaping carbon nanostructures by controlling the synthesis process

    NASA Astrophysics Data System (ADS)

    Merkulov, Vladimir I.; Guillorn, Michael A.; Lowndes, Douglas H.; Simpson, Michael L.; Voelkl, Edgar

    2001-08-01

    The ability to control the nanoscale shape of nanostructures in a large-scale synthesis process is an essential and elusive goal of nanotechnology research. Here, we report significant progress toward that goal. We have developed a technique that enables controlled synthesis of nanoscale carbon structures with conical and cylinder-on-cone shapes and provides the capability to dynamically change the nanostructure shape during the synthesis process. In addition, we present a phenomenological model that explains the formation of these nanostructures and provides insight into methods for precisely engineering their shape. Since the growth process we report is highly deterministic in allowing large-scale synthesis of precisely engineered nanoscale components at defined locations, our approach provides an important tool for a practical nanotechnology.

  1. Automatic detection of health changes using statistical process control techniques on measured transfer times of elderly.

    PubMed

    Baldewijns, Greet; Luca, Stijn; Nagels, William; Vanrumste, Bart; Croonenborghs, Tom

    2015-01-01

    It has been shown that gait speed and transfer times are good measures of functional ability in elderly. However, data currently acquired by systems that measure either gait speed or transfer times in the homes of elderly people require manual reviewing by healthcare workers. This reviewing process is time-consuming. To alleviate this burden, this paper proposes the use of statistical process control methods to automatically detect both positive and negative changes in transfer times. Three SPC techniques: tabular CUSUM, standardized CUSUM and EWMA, known for their ability to detect small shifts in the data, are evaluated on simulated transfer times. This analysis shows that EWMA is the best-suited method with a detection accuracy of 82% and an average detection time of 9.64 days.

  2. Research on the Intensive Material Management System of Biomass Power Plant

    NASA Astrophysics Data System (ADS)

    Zhang, Ruosi; Hao, Tianyi; Li, Yunxiao; Zhang, Fangqing; Ding, Sheng

    2017-05-01

    In view of the universal problem which the material management is loose, and lack of standardization and interactive real-time in the biomass power plant, a system based on the method of intensive management is proposed in this paper to control the whole process of power plant material. By analysing the whole process of power plant material management and applying the Internet of Things, the method can simplify the management process. By making use of the resources to maximize and data mining, material utilization, circulation rate and quality control management can be improved. The system has been applied in Gaotang power plant, which raised the level of materials management and economic effectiveness greatly. It has an important significance for safe, cost-effective and highly efficient operation of the plant.

  3. Process system and method for fabricating submicron field emission cathodes

    DOEpatents

    Jankowski, A.F.; Hayes, J.P.

    1998-05-05

    A process method and system for making field emission cathodes exists. The deposition source divergence is controlled to produce field emission cathodes with height-to-base aspect ratios that are uniform over large substrate surface areas while using very short source-to-substrate distances. The rate of hole closure is controlled from the cone source. The substrate surface is coated in well defined increments. The deposition source is apertured to coat pixel areas on the substrate. The entire substrate is coated using a manipulator to incrementally move the whole substrate surface past the deposition source. Either collimated sputtering or evaporative deposition sources can be used. The position of the aperture and its size and shape are used to control the field emission cathode size and shape. 3 figs.

  4. Process system and method for fabricating submicron field emission cathodes

    DOEpatents

    Jankowski, Alan F.; Hayes, Jeffrey P.

    1998-01-01

    A process method and system for making field emission cathodes exists. The deposition source divergence is controlled to produce field emission cathodes with height-to-base aspect ratios that are uniform over large substrate surface areas while using very short source-to-substrate distances. The rate of hole closure is controlled from the cone source. The substrate surface is coated in well defined increments. The deposition source is apertured to coat pixel areas on the substrate. The entire substrate is coated using a manipulator to incrementally move the whole substrate surface past the deposition source. Either collimated sputtering or evaporative deposition sources can be used. The position of the aperture and its size and shape are used to control the field emission cathode size and shape.

  5. Fully chip-embedded automation of a multi-step lab-on-a-chip process using a modularized timer circuit.

    PubMed

    Kang, Junsu; Lee, Donghyeon; Heo, Young Jin; Chung, Wan Kyun

    2017-11-07

    For highly-integrated microfluidic systems, an actuation system is necessary to control the flow; however, the bulk of actuation devices including pumps or valves has impeded the broad application of integrated microfluidic systems. Here, we suggest a microfluidic process control method based on built-in microfluidic circuits. The circuit is composed of a fluidic timer circuit and a pneumatic logic circuit. The fluidic timer circuit is a serial connection of modularized timer units, which sequentially pass high pressure to the pneumatic logic circuit. The pneumatic logic circuit is a NOR gate array designed to control the liquid-controlling process. By using the timer circuit as a built-in signal generator, multi-step processes could be done totally inside the microchip without any external controller. The timer circuit uses only two valves per unit, and the number of process steps can be extended without limitation by adding timer units. As a demonstration, an automation chip has been designed for a six-step droplet treatment, which entails 1) loading, 2) separation, 3) reagent injection, 4) incubation, 5) clearing and 6) unloading. Each process was successfully performed for a pre-defined step-time without any external control device.

  6. Machine Learning EEG to Predict Cognitive Functioning and Processing Speed Over a 2-Year Period in Multiple Sclerosis Patients and Controls.

    PubMed

    Kiiski, Hanni; Jollans, Lee; Donnchadha, Seán Ó; Nolan, Hugh; Lonergan, Róisín; Kelly, Siobhán; O'Brien, Marie Claire; Kinsella, Katie; Bramham, Jessica; Burke, Teresa; Hutchinson, Michael; Tubridy, Niall; Reilly, Richard B; Whelan, Robert

    2018-05-01

    Event-related potentials (ERPs) show promise to be objective indicators of cognitive functioning. The aim of the study was to examine if ERPs recorded during an oddball task would predict cognitive functioning and information processing speed in Multiple Sclerosis (MS) patients and controls at the individual level. Seventy-eight participants (35 MS patients, 43 healthy age-matched controls) completed visual and auditory 2- and 3-stimulus oddball tasks with 128-channel EEG, and a neuropsychological battery, at baseline (month 0) and at Months 13 and 26. ERPs from 0 to 700 ms and across the whole scalp were transformed into 1728 individual spatio-temporal datapoints per participant. A machine learning method that included penalized linear regression used the entire spatio-temporal ERP to predict composite scores of both cognitive functioning and processing speed at baseline (month 0), and months 13 and 26. The results showed ERPs during the visual oddball tasks could predict cognitive functioning and information processing speed at baseline and a year later in a sample of MS patients and healthy controls. In contrast, ERPs during auditory tasks were not predictive of cognitive performance. These objective neurophysiological indicators of cognitive functioning and processing speed, and machine learning methods that can interrogate high-dimensional data, show promise in outcome prediction.

  7. Massively Parallel Signal Processing using the Graphics Processing Unit for Real-Time Brain-Computer Interface Feature Extraction.

    PubMed

    Wilson, J Adam; Williams, Justin C

    2009-01-01

    The clock speeds of modern computer processors have nearly plateaued in the past 5 years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a graphics card [graphics processing unit (GPU)] was developed for real-time neural signal processing of a brain-computer interface (BCI). The NVIDIA CUDA system was used to offload processing to the GPU, which is capable of running many operations in parallel, potentially greatly increasing the speed of existing algorithms. The BCI system records many channels of data, which are processed and translated into a control signal, such as the movement of a computer cursor. This signal processing chain involves computing a matrix-matrix multiplication (i.e., a spatial filter), followed by calculating the power spectral density on every channel using an auto-regressive method, and finally classifying appropriate features for control. In this study, the first two computationally intensive steps were implemented on the GPU, and the speed was compared to both the current implementation and a central processing unit-based implementation that uses multi-threading. Significant performance gains were obtained with GPU processing: the current implementation processed 1000 channels of 250 ms in 933 ms, while the new GPU method took only 27 ms, an improvement of nearly 35 times.

  8. Study of the modifications needed for efficient operation of NASTRAN on the Control Data Corporation STAR-100 computer

    NASA Technical Reports Server (NTRS)

    1975-01-01

    NASA structural analysis (NASTRAN) computer program is operational on three series of third generation computers. The problem and difficulties involved in adapting NASTRAN to a fourth generation computer, namely, the Control Data STAR-100, are discussed. The salient features which distinguish Control Data STAR-100 from third generation computers are hardware vector processing capability and virtual memory. A feasible method is presented for transferring NASTRAN to Control Data STAR-100 system while retaining much of the machine-independent code. Basic matrix operations are noted for optimization for vector processing.

  9. Artificial Intelligence Methods in Pursuit Evasion Differential Games

    DTIC Science & Technology

    1990-07-30

    objectives, sometimes with fuzzy ones. Classical optimization, control or game theoretic methods are insufficient for their resolution. I Solution...OVERALL SATISFACTION WITH SCHOOL 120 FIGURE 5.13 EXAMPLE AHP HIERARCHY FOR CHOOSING MOST APPROPRIATE DIFFERENTIAL GAME AND PARAMETRIZATION 125 FIGURE 5.14...the Analytical Hierarchy Process originated by T.L. Saaty of the Wharton School. The Analytic Hierarchy Process ( AHP ) is a general theory of

  10. Graphitic carbon stabilized silver nanoparticles synthesized by a simple chemical precursor method

    NASA Astrophysics Data System (ADS)

    Soni, Bhasker; Biswas, Somnath

    2018-04-01

    Monodispersed graphitic carbon stabilized silver nanoparticles (AgNPs) were synthesized following a simple chemical precursor method. The precursor was obtained by a controlled reduction of Ag+ in aqueous solution of poly-vinyl alcohol (PVA) and sucrose. The process allows precise control over the morphology of the AgNPs along with in situ formation of a surface stabilization layer of graphitic carbon.

  11. Quality Control of High-Dose-Rate Brachytherapy: Treatment Delivery Analysis Using Statistical Process Control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Able, Charles M., E-mail: cable@wfubmc.edu; Bright, Megan; Frizzell, Bart

    Purpose: Statistical process control (SPC) is a quality control method used to ensure that a process is well controlled and operates with little variation. This study determined whether SPC was a viable technique for evaluating the proper operation of a high-dose-rate (HDR) brachytherapy treatment delivery system. Methods and Materials: A surrogate prostate patient was developed using Vyse ordnance gelatin. A total of 10 metal oxide semiconductor field-effect transistors (MOSFETs) were placed from prostate base to apex. Computed tomography guidance was used to accurately position the first detector in each train at the base. The plan consisted of 12 needles withmore » 129 dwell positions delivering a prescribed peripheral dose of 200 cGy. Sixteen accurate treatment trials were delivered as planned. Subsequently, a number of treatments were delivered with errors introduced, including wrong patient, wrong source calibration, wrong connection sequence, single needle displaced inferiorly 5 mm, and entire implant displaced 2 mm and 4 mm inferiorly. Two process behavior charts (PBC), an individual and a moving range chart, were developed for each dosimeter location. Results: There were 4 false positives resulting from 160 measurements from 16 accurately delivered treatments. For the inaccurately delivered treatments, the PBC indicated that measurements made at the periphery and apex (regions of high-dose gradient) were much more sensitive to treatment delivery errors. All errors introduced were correctly identified by either the individual or the moving range PBC in the apex region. Measurements at the urethra and base were less sensitive to errors. Conclusions: SPC is a viable method for assessing the quality of HDR treatment delivery. Further development is necessary to determine the most effective dose sampling, to ensure reproducible evaluation of treatment delivery accuracy.« less

  12. Laser Raman detection for oral cancer based on an adaptive Gaussian process classification method with posterior probabilities

    NASA Astrophysics Data System (ADS)

    Du, Zhanwei; Yang, Yongjian; Bai, Yuan; Wang, Lijun; Su, Le; Chen, Yong; Li, Xianchang; Zhou, Xiaodong; Jia, Jun; Shen, Aiguo; Hu, Jiming

    2013-03-01

    The existing methods for early and differential diagnosis of oral cancer are limited due to the unapparent early symptoms and the imperfect imaging examination methods. In this paper, the classification models of oral adenocarcinoma, carcinoma tissues and a control group with just four features are established by utilizing the hybrid Gaussian process (HGP) classification algorithm, with the introduction of the mechanisms of noise reduction and posterior probability. HGP shows much better performance in the experimental results. During the experimental process, oral tissues were divided into three groups, adenocarcinoma (n = 87), carcinoma (n = 100) and the control group (n = 134). The spectral data for these groups were collected. The prospective application of the proposed HGP classification method improved the diagnostic sensitivity to 56.35% and the specificity to about 70.00%, and resulted in a Matthews correlation coefficient (MCC) of 0.36. It is proved that the utilization of HGP in LRS detection analysis for the diagnosis of oral cancer gives accurate results. The prospect of application is also satisfactory.

  13. Accurate acceleration of kinetic Monte Carlo simulations through the modification of rate constants.

    PubMed

    Chatterjee, Abhijit; Voter, Arthur F

    2010-05-21

    We present a novel computational algorithm called the accelerated superbasin kinetic Monte Carlo (AS-KMC) method that enables a more efficient study of rare-event dynamics than the standard KMC method while maintaining control over the error. In AS-KMC, the rate constants for processes that are observed many times are lowered during the course of a simulation. As a result, rare processes are observed more frequently than in KMC and the time progresses faster. We first derive error estimates for AS-KMC when the rate constants are modified. These error estimates are next employed to develop a procedure for lowering process rates with control over the maximum error. Finally, numerical calculations are performed to demonstrate that the AS-KMC method captures the correct dynamics, while providing significant CPU savings over KMC in most cases. We show that the AS-KMC method can be employed with any KMC model, even when no time scale separation is present (although in such cases no computational speed-up is observed), without requiring the knowledge of various time scales present in the system.

  14. Dynamic Rod Worth Measurement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chao, Y.A.; Chapman, D.M.; Hill, D.J.

    2000-12-15

    The dynamic rod worth measurement (DRWM) technique is a method of quickly validating the predicted bank worth of control rods and shutdown rods. The DRWM analytic method is based on three-dimensional, space-time kinetic simulations of the rapid rod movements. Its measurement data is processed with an advanced digital reactivity computer. DRWM has been used as the method of bank worth validation at numerous plant startups with excellent results. The process and methodology of DRWM are described, and the measurement results of using DRWM are presented.

  15. Metal matrix composite fabrication processes for high performance aerospace structures

    NASA Astrophysics Data System (ADS)

    Ponzi, C.

    A survey is conducted of extant methods of metal matrix composite (MMC) production in order to serve as a basis for prospective MMC users' selection of a matrix/reinforcement combination, cost-effective primary fabrication methods, and secondary fabrication techniques for the achievement of desired performance levels. Attention is given to the illustrative cases of structural fittings, control-surface connecting rods, hypersonic aircraft air inlet ramps, helicopter swash plates, and turbine rotor disks. Methods for technical and cost analysis modeling useful in process optimization are noted.

  16. Research on the optimization of quota design in real estate

    NASA Astrophysics Data System (ADS)

    Sun, Chunling; Ma, Susu; Zhong, Weichao

    2017-11-01

    Quota design is one of the effective methods of cost control in real estate development project and widely used in the current real estate development project to control the engineering construction cost, but quota design have many deficiencies in design process. For this purpose, this paper put forward a method to achieve investment control of real estate development project, which combine quota design and value engineering(VE) at the stage of design. Specifically, it’s an optimizing for the structure of quota design. At first, determine the design limits by investment estimate value, then using VE to carry on initial allocation of design limits and gain the functional target cost, finally, consider the whole life cycle cost (LCC) and operational problem in practical application to finish complex correction for the functional target cost. The improved process can control the project cost more effectively. It not only can control investment in a certain range, but also make the project realize maximum value within investment.

  17. Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McGoldrick, P.R.

    1981-01-01

    The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control roommore » consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed.« less

  18. A Combined Adaptive Neural Network and Nonlinear Model Predictive Control for Multirate Networked Industrial Process Control.

    PubMed

    Wang, Tong; Gao, Huijun; Qiu, Jianbin

    2016-02-01

    This paper investigates the multirate networked industrial process control problem in double-layer architecture. First, the output tracking problem for sampled-data nonlinear plant at device layer with sampling period T(d) is investigated using adaptive neural network (NN) control, and it is shown that the outputs of subsystems at device layer can track the decomposed setpoints. Then, the outputs and inputs of the device layer subsystems are sampled with sampling period T(u) at operation layer to form the index prediction, which is used to predict the overall performance index at lower frequency. Radial basis function NN is utilized as the prediction function due to its approximation ability. Then, considering the dynamics of the overall closed-loop system, nonlinear model predictive control method is proposed to guarantee the system stability and compensate the network-induced delays and packet dropouts. Finally, a continuous stirred tank reactor system is given in the simulation part to demonstrate the effectiveness of the proposed method.

  19. Method and system for fault accommodation of machines

    NASA Technical Reports Server (NTRS)

    Goebel, Kai Frank (Inventor); Subbu, Rajesh Venkat (Inventor); Rausch, Randal Thomas (Inventor); Frederick, Dean Kimball (Inventor)

    2011-01-01

    A method for multi-objective fault accommodation using predictive modeling is disclosed. The method includes using a simulated machine that simulates a faulted actual machine, and using a simulated controller that simulates an actual controller. A multi-objective optimization process is performed, based on specified control settings for the simulated controller and specified operational scenarios for the simulated machine controlled by the simulated controller, to generate a Pareto frontier-based solution space relating performance of the simulated machine to settings of the simulated controller, including adjustment to the operational scenarios to represent a fault condition of the simulated machine. Control settings of the actual controller are adjusted, represented by the simulated controller, for controlling the actual machine, represented by the simulated machine, in response to a fault condition of the actual machine, based on the Pareto frontier-based solution space, to maximize desirable operational conditions and minimize undesirable operational conditions while operating the actual machine in a region of the solution space defined by the Pareto frontier.

  20. A Computer Model of the Evaporator for the Development of an Automatic Control System

    NASA Astrophysics Data System (ADS)

    Kozin, K. A.; Efremov, E. V.; Kabrysheva, O. P.; Grachev, M. I.

    2016-08-01

    For the implementation of a closed nuclear fuel cycle it is necessary to carry out a series of experimental studies to justify the choice of technology. In addition, the operation of the radiochemical plant is impossible without high-quality automatic control systems. In the technologies of spent nuclear fuel reprocessing, the method of continuous evaporation is often used for a solution conditioning. Therefore, the effective continuous technological process will depend on the operation of the evaporation equipment. Its essential difference from similar devices is a small size. In this paper the method of mathematic simulation is applied for the investigation of one-effect evaporator with an external heating chamber. Detailed modelling is quite difficult because the phase equilibrium dynamics of the evaporation process is not described. Moreover, there is a relationship with the other process units. The results proved that the study subject is a MIMO plant, nonlinear over separate control channels and not selfbalancing. Adequacy was tested using the experimental data obtained at the laboratory evaporation unit.

  1. Framework for robot skill learning using reinforcement learning

    NASA Astrophysics Data System (ADS)

    Wei, Yingzi; Zhao, Mingyang

    2003-09-01

    Robot acquiring skill is a process similar to human skill learning. Reinforcement learning (RL) is an on-line actor critic method for a robot to develop its skill. The reinforcement function has become the critical component for its effect of evaluating the action and guiding the learning process. We present an augmented reward function that provides a new way for RL controller to incorporate prior knowledge and experience into the RL controller. Also, the difference form of augmented reward function is considered carefully. The additional reward beyond conventional reward will provide more heuristic information for RL. In this paper, we present a strategy for the task of complex skill learning. Automatic robot shaping policy is to dissolve the complex skill into a hierarchical learning process. The new form of value function is introduced to attain smooth motion switching swiftly. We present a formal, but practical, framework for robot skill learning and also illustrate with an example the utility of method for learning skilled robot control on line.

  2. An optimized high-performance liquid chromatography (HPLC) method for benzoylmesaconine determination in Radix Aconiti Lateralis Preparata (Fuzi, aconite roots) and its products

    PubMed Central

    Xie, Ying; Zhou, Hua; Wong, Yuen Fan; Liu, Zhongqiu; Xu, Hongxi; Jiang, Zhihong; Liu, Liang

    2008-01-01

    Background Benzoylmesaconine (BMA) is the main Aconitum alkaloid in Radix Aconiti Lateralis Preparata (Fuzi, aconite roots) with potent pharmacological activities, such as analgesia and anti-inflammation. The present study developed a simple and reliable method using BMA as a marker compound for the quality control of processed aconite roots and their products. Methods After extraction, a high-performance liquid chromatography (HPLC) determination of BMA was conducted on a RP-C18 column by gradient elution with acetonitrile and aqueous phase, containing 0.1% phosphoric acid adjusted with triethylamine to pH 3.0. Results A distinct peak profile was obtained and separation of BMA was achieved. Method validation showed that the relative standard deviations (RSDs) of the precision of BMA in all intra-day and inter-day assays were less than 1.36%, and that the average recovery rate was 96.95%. Quantitative analysis of BMA showed that the content of BMA varied significantly in processed aconite roots and their products. Conclusion This HPLC method using BMA as a marker compound is applicable to the quality control of processed aconite roots and their products. PMID:18513409

  3. Six Sigma methods applied to cryogenic coolers assembly line

    NASA Astrophysics Data System (ADS)

    Ventre, Jean-Marc; Germain-Lacour, Michel; Martin, Jean-Yves; Cauquil, Jean-Marc; Benschop, Tonny; Griot, René

    2009-05-01

    Six Sigma method have been applied to manufacturing process of a rotary Stirling cooler: RM2. Name of the project is NoVa as main goal of the Six Sigma approach is to reduce variability (No Variability). Project has been based on the DMAIC guideline following five stages: Define, Measure, Analyse, Improve, Control. Objective has been set on the rate of coolers succeeding performance at first attempt with a goal value of 95%. A team has been gathered involving people and skills acting on the RM2 manufacturing line. Measurement System Analysis (MSA) has been applied to test bench and results after R&R gage show that measurement is one of the root cause for variability in RM2 process. Two more root causes have been identified by the team after process mapping analysis: regenerator filling factor and cleaning procedure. Causes for measurement variability have been identified and eradicated as shown by new results from R&R gage. Experimental results show that regenerator filling factor impacts process variability and affects yield. Improved process haven been set after new calibration process for test bench, new filling procedure for regenerator and an additional cleaning stage have been implemented. The objective for 95% coolers succeeding performance test at first attempt has been reached and kept for a significant period. RM2 manufacturing process is now managed according to Statistical Process Control based on control charts. Improvement in process capability have enabled introduction of sample testing procedure before delivery.

  4. Optimal filtering and Bayesian detection for friction-based diagnostics in machines.

    PubMed

    Ray, L R; Townsend, J R; Ramasubramanian, A

    2001-01-01

    Non-model-based diagnostic methods typically rely on measured signals that must be empirically related to process behavior or incipient faults. The difficulty in interpreting a signal that is indirectly related to the fundamental process behavior is significant. This paper presents an integrated non-model and model-based approach to detecting when process behavior varies from a proposed model. The method, which is based on nonlinear filtering combined with maximum likelihood hypothesis testing, is applicable to dynamic systems whose constitutive model is well known, and whose process inputs are poorly known. Here, the method is applied to friction estimation and diagnosis during motion control in a rotating machine. A nonlinear observer estimates friction torque in a machine from shaft angular position measurements and the known input voltage to the motor. The resulting friction torque estimate can be analyzed directly for statistical abnormalities, or it can be directly compared to friction torque outputs of an applicable friction process model in order to diagnose faults or model variations. Nonlinear estimation of friction torque provides a variable on which to apply diagnostic methods that is directly related to model variations or faults. The method is evaluated experimentally by its ability to detect normal load variations in a closed-loop controlled motor driven inertia with bearing friction and an artificially-induced external line contact. Results show an ability to detect statistically significant changes in friction characteristics induced by normal load variations over a wide range of underlying friction behaviors.

  5. Surface defect detection in tiling Industries using digital image processing methods: analysis and evaluation.

    PubMed

    Karimi, Mohammad H; Asemani, Davud

    2014-05-01

    Ceramic and tile industries should indispensably include a grading stage to quantify the quality of products. Actually, human control systems are often used for grading purposes. An automatic grading system is essential to enhance the quality control and marketing of the products. Since there generally exist six different types of defects originating from various stages of tile manufacturing lines with distinct textures and morphologies, many image processing techniques have been proposed for defect detection. In this paper, a survey has been made on the pattern recognition and image processing algorithms which have been used to detect surface defects. Each method appears to be limited for detecting some subgroup of defects. The detection techniques may be divided into three main groups: statistical pattern recognition, feature vector extraction and texture/image classification. The methods such as wavelet transform, filtering, morphology and contourlet transform are more effective for pre-processing tasks. Others including statistical methods, neural networks and model-based algorithms can be applied to extract the surface defects. Although, statistical methods are often appropriate for identification of large defects such as Spots, but techniques such as wavelet processing provide an acceptable response for detection of small defects such as Pinhole. A thorough survey is made in this paper on the existing algorithms in each subgroup. Also, the evaluation parameters are discussed including supervised and unsupervised parameters. Using various performance parameters, different defect detection algorithms are compared and evaluated. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Efficient model learning methods for actor-critic control.

    PubMed

    Grondman, Ivo; Vaandrager, Maarten; Buşoniu, Lucian; Babuska, Robert; Schuitema, Erik

    2012-06-01

    We propose two new actor-critic algorithms for reinforcement learning. Both algorithms use local linear regression (LLR) to learn approximations of the functions involved. A crucial feature of the algorithms is that they also learn a process model, and this, in combination with LLR, provides an efficient policy update for faster learning. The first algorithm uses a novel model-based update rule for the actor parameters. The second algorithm does not use an explicit actor but learns a reference model which represents a desired behavior, from which desired control actions can be calculated using the inverse of the learned process model. The two novel methods and a standard actor-critic algorithm are applied to the pendulum swing-up problem, in which the novel methods achieve faster learning than the standard algorithm.

  7. Preliminary study of ultrasonic structural quality control of Swiss-type cheese.

    PubMed

    Eskelinen, J J; Alavuotunki, A P; Haeggström, E; Alatossava, T

    2007-09-01

    There is demand for a new nondestructive cheese-structure analysis method for Swiss-type cheese. Such a method would provide the cheese-making industry the means to enhance process control and quality assurance. This paper presents a feasibility study on ultrasonic monitoring of the structural quality of Swiss cheese by using a single-transducer 2-MHz longitudinal mode pulse-echo setup. A volumetric ultrasonic image of a cheese sample featuring gas holes (cheese-eyes) and defects (cracks) in the scan area is presented. The image is compared with an optical reference image constructed from dissection images of the same sample. The results show that the ultrasonic method is capable of monitoring the gas-solid structure of the cheese during the ripening process. Moreover, the method can be used to detect and to characterize cheese-eyes and cracks in ripened cheese. Industrial application demands were taken into account when conducting the measurements.

  8. Controlled assembly of jammed colloidal shells on fluid droplets.

    PubMed

    Subramaniam, Anand Bala; Abkarian, Manouk; Stone, Howard A

    2005-07-01

    Assembly of colloidal particles on fluid interfaces is a promising technique for synthesizing two-dimensional microcrystalline materials useful in fields as diverse as biomedicine, materials science, mineral flotation and food processing. Current approaches rely on bulk emulsification methods, require further chemical and thermal treatments, and are restrictive with respect to the materials used. The development of methods that exploit the great potential of interfacial assembly for producing tailored materials have been hampered by the lack of understanding of the assembly process. Here we report a microfluidic method that allows direct visualization and understanding of the dynamics of colloidal crystal growth on curved interfaces. The crystals are periodically ejected to form stable jammed shells, which we refer to as colloidal armour. We propose that the energetic barriers to interfacial crystal growth and organization can be overcome by targeted delivery of colloidal particles through hydrodynamic flows. Our method allows an unprecedented degree of control over armour composition, size and stability.

  9. Controlled assembly of jammed colloidal shells on fluid droplets

    NASA Astrophysics Data System (ADS)

    Subramaniam, Anand Bala; Abkarian, Manouk; Stone, Howard A.

    2005-07-01

    Assembly of colloidal particles on fluid interfaces is a promising technique for synthesizing two-dimensional microcrystalline materials useful in fields as diverse as biomedicine, materials science, mineral flotation and food processing. Current approaches rely on bulk emulsification methods, require further chemical and thermal treatments, and are restrictive with respect to the materials used. The development of methods that exploit the great potential of interfacial assembly for producing tailored materials have been hampered by the lack of understanding of the assembly process. Here we report a microfluidic method that allows direct visualization and understanding of the dynamics of colloidal crystal growth on curved interfaces. The crystals are periodically ejected to form stable jammed shells, which we refer to as colloidal armour. We propose that the energetic barriers to interfacial crystal growth and organization can be overcome by targeted delivery of colloidal particles through hydrodynamic flows. Our method allows an unprecedented degree of control over armour composition, size and stability.

  10. Process for injecting liquid in moving natural gas streams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rivers, J.B. Jr.; Budke, H.T. Jr.

    1979-01-02

    Western Chemical Co.'s simplified, low-cost method of treating pressurized, moving natural gas streams in order to control problems created by entrained water facilitates the downstream treatment of the gas and increases product yields by lessening the formation of oil and water emulsions and hydrates that can coat and clog the processing equipment, while also minimizing equipment corrosion. The method involves introducing into the moving gas stream an agent that includes a polymer having recurring quaternized pyridinium groups for controlling the emulsion, hydrate, and corrosion problems. The method is especially effective when the entrained water contains surfactants, detergents, soaps, etc. Inmore » preferred forms, a low-molecular-weight copolymer of styrene and 2-vinyl pyridine dispersed in water is atomized into the gas stream adjacent to cooling and scrubbing stations. The method is particularly useful in connection with natural gas products plants.« less

  11. Access Control and Processing Studies for Ground Satellite Mobile Communications/Surveillance Systems

    DOT National Transportation Integrated Search

    1974-06-01

    The report synthesizes a set of satellite communications systems configurations to provide services to aircraft flying oceanic routes. These configurations are combined with access control methods to form complete systems. These systems are analyzed ...

  12. Empirical mode decomposition processing to improve multifocal-visual-evoked-potential signal analysis in multiple sclerosis

    PubMed Central

    2018-01-01

    Objective To study the performance of multifocal-visual-evoked-potential (mfVEP) signals filtered using empirical mode decomposition (EMD) in discriminating, based on amplitude, between control and multiple sclerosis (MS) patient groups, and to reduce variability in interocular latency in control subjects. Methods MfVEP signals were obtained from controls, clinically definitive MS and MS-risk progression patients (radiologically isolated syndrome (RIS) and clinically isolated syndrome (CIS)). The conventional method of processing mfVEPs consists of using a 1–35 Hz bandpass frequency filter (XDFT). The EMD algorithm was used to decompose the XDFT signals into several intrinsic mode functions (IMFs). This signal processing was assessed by computing the amplitudes and latencies of the XDFT and IMF signals (XEMD). The amplitudes from the full visual field and from ring 5 (9.8–15° eccentricity) were studied. The discrimination index was calculated between controls and patients. Interocular latency values were computed from the XDFT and XEMD signals in a control database to study variability. Results Using the amplitude of the mfVEP signals filtered with EMD (XEMD) obtains higher discrimination index values than the conventional method when control, MS-risk progression (RIS and CIS) and MS subjects are studied. The lowest variability in interocular latency computations from the control patient database was obtained by comparing the XEMD signals with the XDFT signals. Even better results (amplitude discrimination and latency variability) were obtained in ring 5 (9.8–15° eccentricity of the visual field). Conclusions Filtering mfVEP signals using the EMD algorithm will result in better identification of subjects at risk of developing MS and better accuracy in latency studies. This could be applied to assess visual cortex activity in MS diagnosis and evolution studies. PMID:29677200

  13. A Proven Method for Meeting Export Control Objectives in Postal and Shipping Sectors

    DTIC Science & Technology

    2015-02-01

    months, the USPIS team developed and implemented an export screening standard operating procedure, implemented new and updated processes and systems ...support and protect the U.S. Postal Service and its employees, infrastructure, and customers; enforce the laws that defend the nation’s mail system ...the incidence of mail shipments violating export control laws, regulations, and standards . • Evaluate current processes and systems and identify

  14. Magnetron Sputtered Pulsed Laser Deposition Scale Up

    DTIC Science & Technology

    2003-08-14

    2:721-726 34 S. J. P. Laube and E. F. Stark, “ Artificial Intellegence in Process Control of Pulsed Laser Deposition”, Proceedings of...The model would be based on mathematical simulation of real process data, neural-networks, or other artificial intelligence methods based on in situ...Laube and E. F. Stark, Proc. Symp. Artificial Intel. Real Time Control, Valencia, Spain, 3-5 Oct. ,1994, p.159-163. International Federation of

  15. Investigate the Effect of Thawing Process on the Self-Assembly of Silk Protein for Tissue Applications.

    PubMed

    Nguyen, Hiep Thi; Luong, Hien Thu; Nguyen, Hai Dai; Tran, Hien Anh; Huynh, Khon Chan; Vo, Toi Van

    2017-01-01

    Biological self-assembly is a process in which building blocks autonomously organize to form stable supermolecules of higher order and complexity through domination of weak, noncovalent interactions. For silk protein, the effect of high incubating temperature on the induction of secondary structure and self-assembly was well investigated. However, the effect of freezing and thawing on silk solution has not been studied. The present work aimed to investigate a new all-aqueous process to form 3D porous silk fibroin matrices using a freezing-assisted self-assembly method. This study proposes an experimental investigation and optimization of environmental parameters for the self-assembly process such as freezing temperature, thawing process, and concentration of silk solution. The optical images demonstrated the possibility and potential of -80ST48 treatment to initialize the self-assembly of silk fibroin as well as controllably fabricate a porous scaffold. Moreover, the micrograph images illustrate the assembly of silk protein chain in 7 days under the treatment of -80ST48 process. The surface morphology characterization proved that this method could control the pore size of porous scaffolds by control of the concentration of silk solution. The animal test showed the support of silk scaffold for cell adhesion and proliferation, as well as the cell migration process in the 3D implantable scaffold.

  16. Investigate the Effect of Thawing Process on the Self-Assembly of Silk Protein for Tissue Applications

    PubMed Central

    Tran, Hien Anh; Huynh, Khon Chan; Vo, Toi Van

    2017-01-01

    Biological self-assembly is a process in which building blocks autonomously organize to form stable supermolecules of higher order and complexity through domination of weak, noncovalent interactions. For silk protein, the effect of high incubating temperature on the induction of secondary structure and self-assembly was well investigated. However, the effect of freezing and thawing on silk solution has not been studied. The present work aimed to investigate a new all-aqueous process to form 3D porous silk fibroin matrices using a freezing-assisted self-assembly method. This study proposes an experimental investigation and optimization of environmental parameters for the self-assembly process such as freezing temperature, thawing process, and concentration of silk solution. The optical images demonstrated the possibility and potential of −80ST48 treatment to initialize the self-assembly of silk fibroin as well as controllably fabricate a porous scaffold. Moreover, the micrograph images illustrate the assembly of silk protein chain in 7 days under the treatment of −80ST48 process. The surface morphology characterization proved that this method could control the pore size of porous scaffolds by control of the concentration of silk solution. The animal test showed the support of silk scaffold for cell adhesion and proliferation, as well as the cell migration process in the 3D implantable scaffold. PMID:28367442

  17. Process identification of the SCR system of coal-fired power plant for de-NOx based on historical operation data.

    PubMed

    Li, Jian; Shi, Raoqiao; Xu, Chuanlong; Wang, Shimin

    2018-05-08

    The selective catalytic reduction (SCR) system, as one principal flue gas treatment method employed for the NO x emission control of the coal-fired power plant, is nonlinear and time-varying with great inertia and large time delay. It is difficult for the present SCR control system to achieve satisfactory performance with the traditional feedback and feedforward control strategies. Although some improved control strategies, such as the Smith predictor control and the model predictive control, have been proposed for this issue, a well-matched identification model is essentially required to realize a superior control of the SCR system. Industrial field experiment is an alternative way to identify the SCR system model in the coal-fired power plant. But it undesirably disturbs the operation system and is costly in time and manpower. In this paper, a process identification model of the SCR system is proposed and developed by applying the asymptotic method to the sufficiently excited data, selected from the original historical operation database of a 350 MW coal-fired power plant according to the condition number of the Fisher information matrix. Numerical simulations are carried out based on the practical historical operation data to evaluate the performance of the proposed model. Results show that the proposed model can efficiently achieve the process identification of the SCR system.

  18. Structural model of control system for hydraulic stepper motor complex

    NASA Astrophysics Data System (ADS)

    Obukhov, A. D.; Dedov, D. L.; Kolodin, A. N.

    2018-03-01

    The article considers the problem of developing a structural model of the control system for a hydraulic stepper drive complex. A comparative analysis of stepper drives and assessment of the applicability of HSM for solving problems, requiring accurate displacement in space with subsequent positioning of the object, are carried out. The presented structural model of the automated control system of the multi-spindle complex of hydraulic stepper drives reflects the main components of the system, as well as the process of its control based on the control signals transfer to the solenoid valves by the controller. The models and methods described in the article can be used to formalize the control process in technical systems based on the application hydraulic stepper drives and allow switching from mechanical control to automated control.

  19. Real-time discrete suboptimal control for systems with input and state delays: Experimental tests on a dehydration process.

    PubMed

    Rodríguez-Guerrero, Liliam; Santos-Sánchez, Omar-Jacobo; Cervantes-Escorcia, Nicolás; Romero, Hugo

    2017-11-01

    This article presents a suboptimal control strategy with finite horizon for affine nonlinear discrete systems with both state and input delays. The Dynamic Programming Approach is used to obtain the suboptimal control sequence, but in order to avoid the computation of the Bellman functional, a numerical approximation of this function is proposed in every step. The feasibility of our proposal is demonstrated via an experimental test on a dehydration process and the obtained results show a good performance and behavior of this process. Then in order to demonstrate the benefits of using this kind of control strategy, the results are compared with a non optimal control strategy, particularly with respect to results produced by an industrial Proportional Integral Derivative (PID) Honeywell controller, which is tuned using the Ziegler-Nichols method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. The Role of Ankle Proprioception for Balance Control in relation to Sports Performance and Injury.

    PubMed

    Han, Jia; Anson, Judith; Waddington, Gordon; Adams, Roger; Liu, Yu

    2015-01-01

    Balance control improvement is one of the most important goals in sports and exercise. Better balance is strongly positively associated with enhanced athletic performance and negatively associated with lower limb sports injuries. Proprioception plays an essential role in balance control, and ankle proprioception is arguably the most important. This paper reviews ankle proprioception and explores synergies with balance control, specifically in a sporting context. Central processing of ankle proprioceptive information, along with other sensory information, enables integration for balance control. When assessing ankle proprioception, the most generalizable findings arise from methods that are ecologically valid, allow proprioceptive signals to be integrated with general vision in the central nervous system, and reflect the signal-in-noise nature of central processing. Ankle proprioceptive intervention concepts driven by such a central processing theory are further proposed and discussed for the improvement of balance control in sport.

  1. The Role of Ankle Proprioception for Balance Control in relation to Sports Performance and Injury

    PubMed Central

    Han, Jia; Waddington, Gordon; Adams, Roger; Liu, Yu

    2015-01-01

    Balance control improvement is one of the most important goals in sports and exercise. Better balance is strongly positively associated with enhanced athletic performance and negatively associated with lower limb sports injuries. Proprioception plays an essential role in balance control, and ankle proprioception is arguably the most important. This paper reviews ankle proprioception and explores synergies with balance control, specifically in a sporting context. Central processing of ankle proprioceptive information, along with other sensory information, enables integration for balance control. When assessing ankle proprioception, the most generalizable findings arise from methods that are ecologically valid, allow proprioceptive signals to be integrated with general vision in the central nervous system, and reflect the signal-in-noise nature of central processing. Ankle proprioceptive intervention concepts driven by such a central processing theory are further proposed and discussed for the improvement of balance control in sport. PMID:26583139

  2. Sliding mode control of dissolved oxygen in an integrated nitrogen removal process in a sequencing batch reactor (SBR).

    PubMed

    Muñoz, C; Young, H; Antileo, C; Bornhardt, C

    2009-01-01

    This paper presents a sliding mode controller (SMC) for dissolved oxygen (DO) in an integrated nitrogen removal process carried out in a suspended biomass sequencing batch reactor (SBR). The SMC performance was compared against an auto-tuning PI controller with parameters adjusted at the beginning of the batch cycle. A method for cancelling the slow DO sensor dynamics was implemented by using a first order model of the sensor. Tests in a lab-scale reactor showed that the SMC offers a better disturbance rejection capability than the auto-tuning PI controller, furthermore providing reasonable performance in a wide range of operation. Thus, SMC becomes an effective robust nonlinear tool to the DO control in this process, being also simple from a computational point of view, allowing its implementation in devices such as industrial programmable logic controllers (PLCs).

  3. AnClim and ProClimDB software for data quality control and homogenization of time series

    NASA Astrophysics Data System (ADS)

    Stepanek, Petr

    2015-04-01

    During the last decade, a software package consisting of AnClim, ProClimDB and LoadData for processing (mainly climatological) data has been created. This software offers a complex solution for processing of climatological time series, starting from loading the data from a central database (e.g. Oracle, software LoadData), through data duality control and homogenization to time series analysis, extreme value evaluations and RCM outputs verification and correction (ProClimDB and AnClim software). The detection of inhomogeneities is carried out on a monthly scale through the application of AnClim, or newly by R functions called from ProClimDB, while quality control, the preparation of reference series and the correction of found breaks is carried out by the ProClimDB software. The software combines many statistical tests, types of reference series and time scales (monthly, seasonal and annual, daily and sub-daily ones). These can be used to create an "ensemble" of solutions, which may be more reliable than any single method. AnClim software is suitable for educational purposes: e.g. for students getting acquainted with methods used in climatology. Built-in graphical tools and comparison of various statistical tests help in better understanding of a given method. ProClimDB is, on the contrary, tool aimed for processing of large climatological datasets. Recently, functions from R may be used within the software making it more efficient in data processing and capable of easy inclusion of new methods (when available under R). An example of usage is easy comparison of methods for correction of inhomogeneities in daily data (HOM of Paul Della-Marta, SPLIDHOM method of Olivier Mestre, DAP - own method, QM of Xiaolan Wang and others). The software is available together with further information on www.climahom.eu . Acknowledgement: this work was partially funded by the project "Building up a multidisciplinary scientific team focused on drought" No. CZ.1.07/2.3.00/20.0248.

  4. Normal contour error measurement on-machine and compensation method for polishing complex surface by MRF

    NASA Astrophysics Data System (ADS)

    Chen, Hua; Chen, Jihong; Wang, Baorui; Zheng, Yongcheng

    2016-10-01

    The Magnetorheological finishing (MRF) process, based on the dwell time method with the constant normal spacing for flexible polishing, would bring out the normal contour error in the fine polishing complex surface such as aspheric surface. The normal contour error would change the ribbon's shape and removal characteristics of consistency for MRF. Based on continuously scanning the normal spacing between the workpiece and the finder by the laser range finder, the novel method was put forward to measure the normal contour errors while polishing complex surface on the machining track. The normal contour errors was measured dynamically, by which the workpiece's clamping precision, multi-axis machining NC program and the dynamic performance of the MRF machine were achieved for the verification and security check of the MRF process. The unit for measuring the normal contour errors of complex surface on-machine was designed. Based on the measurement unit's results as feedback to adjust the parameters of the feed forward control and the multi-axis machining, the optimized servo control method was presented to compensate the normal contour errors. The experiment for polishing 180mm × 180mm aspherical workpiece of fused silica by MRF was set up to validate the method. The results show that the normal contour error was controlled in less than 10um. And the PV value of the polished surface accuracy was improved from 0.95λ to 0.09λ under the conditions of the same process parameters. The technology in the paper has been being applied in the PKC600-Q1 MRF machine developed by the China Academe of Engineering Physics for engineering application since 2014. It is being used in the national huge optical engineering for processing the ultra-precision optical parts.

  5. No control genes required: Bayesian analysis of qRT-PCR data.

    PubMed

    Matz, Mikhail V; Wright, Rachel M; Scott, James G

    2013-01-01

    Model-based analysis of data from quantitative reverse-transcription PCR (qRT-PCR) is potentially more powerful and versatile than traditional methods. Yet existing model-based approaches cannot properly deal with the higher sampling variances associated with low-abundant targets, nor do they provide a natural way to incorporate assumptions about the stability of control genes directly into the model-fitting process. In our method, raw qPCR data are represented as molecule counts, and described using generalized linear mixed models under Poisson-lognormal error. A Markov Chain Monte Carlo (MCMC) algorithm is used to sample from the joint posterior distribution over all model parameters, thereby estimating the effects of all experimental factors on the expression of every gene. The Poisson-based model allows for the correct specification of the mean-variance relationship of the PCR amplification process, and can also glean information from instances of no amplification (zero counts). Our method is very flexible with respect to control genes: any prior knowledge about the expected degree of their stability can be directly incorporated into the model. Yet the method provides sensible answers without such assumptions, or even in the complete absence of control genes. We also present a natural Bayesian analogue of the "classic" analysis, which uses standard data pre-processing steps (logarithmic transformation and multi-gene normalization) but estimates all gene expression changes jointly within a single model. The new methods are considerably more flexible and powerful than the standard delta-delta Ct analysis based on pairwise t-tests. Our methodology expands the applicability of the relative-quantification analysis protocol all the way to the lowest-abundance targets, and provides a novel opportunity to analyze qRT-PCR data without making any assumptions concerning target stability. These procedures have been implemented as the MCMC.qpcr package in R.

  6. Make no mistake—errors can be controlled*

    PubMed Central

    Hinckley, C

    2003-01-01

    

 Traditional quality control methods identify "variation" as the enemy. However, the control of variation by itself can never achieve the remarkably low non-conformance rates of world class quality leaders. Because the control of variation does not achieve the highest levels of quality, an inordinate focus on these techniques obscures key quality improvement opportunities and results in unnecessary pain and suffering for patients, and embarrassment, litigation, and loss of revenue for healthcare providers. Recent experience has shown that mistakes are the most common cause of problems in health care as well as in other industrial environments. Excessive product and process complexity contributes to both excessive variation and unnecessary mistakes. The best methods for controlling variation, mistakes, and complexity are each a form of mistake proofing. Using these mistake proofing techniques, virtually every mistake and non-conformance can be controlled at a fraction of the cost of traditional quality control methods. PMID:14532368

  7. Identification of control targets in Boolean molecular network models via computational algebra.

    PubMed

    Murrugarra, David; Veliz-Cuba, Alan; Aguilar, Boris; Laubenbacher, Reinhard

    2016-09-23

    Many problems in biomedicine and other areas of the life sciences can be characterized as control problems, with the goal of finding strategies to change a disease or otherwise undesirable state of a biological system into another, more desirable, state through an intervention, such as a drug or other therapeutic treatment. The identification of such strategies is typically based on a mathematical model of the process to be altered through targeted control inputs. This paper focuses on processes at the molecular level that determine the state of an individual cell, involving signaling or gene regulation. The mathematical model type considered is that of Boolean networks. The potential control targets can be represented by a set of nodes and edges that can be manipulated to produce a desired effect on the system. This paper presents a method for the identification of potential intervention targets in Boolean molecular network models using algebraic techniques. The approach exploits an algebraic representation of Boolean networks to encode the control candidates in the network wiring diagram as the solutions of a system of polynomials equations, and then uses computational algebra techniques to find such controllers. The control methods in this paper are validated through the identification of combinatorial interventions in the signaling pathways of previously reported control targets in two well studied systems, a p53-mdm2 network and a blood T cell lymphocyte granular leukemia survival signaling network. Supplementary data is available online and our code in Macaulay2 and Matlab are available via http://www.ms.uky.edu/~dmu228/ControlAlg . This paper presents a novel method for the identification of intervention targets in Boolean network models. The results in this paper show that the proposed methods are useful and efficient for moderately large networks.

  8. [Design of a HACCP Plan for the Gouda-type cheesemaking process in a milk processing plant].

    PubMed

    Dávila, Jacqueline; Reyes, Genara; Corzo, Otoniel

    2006-03-01

    The Hazard Analysis and Critical Control Point (HACCP) is a preventive and systematic method used to identify, assess and control of the hazards related with raw material, ingredients, processing, marketing and intended consumer in order to assure the safety of the food. The aim of this study was to design a HACCP plan for implementing in a Gouda-type cheese-making process in a dairy processing plant. The used methodology was based in the application of the seven principles of the HACCP, the information from the plant about the compliment of the pre-requisite programs (70-80%), the experience of the HACCP team and the sequence of stages settles down by the COVENIN standard 3802 for implementing the HACCP system. A HACCP plan was proposed with the scope, the selection of HACCP team, the description of the product and the intended use, the flow diagram of the process, the hazard analysis and the control table of the plan with the critical control points (CCP). The following CCP were identified in the process: pasteurization, coagulation and ripening.

  9. Stabilization and analytical tuning rule of double-loop control scheme for unstable dead-time process

    NASA Astrophysics Data System (ADS)

    Ugon, B.; Nandong, J.; Zang, Z.

    2017-06-01

    The presence of unstable dead-time systems in process plants often leads to a daunting challenge in the design of standard PID controllers, which are not only intended to provide close-loop stability but also to give good performance-robustness overall. In this paper, we conduct stability analysis on a double-loop control scheme based on the Routh-Hurwitz stability criteria. We propose to use this unstable double-loop control scheme which employs two P/PID controllers to control first-order or second-order unstable dead-time processes typically found in process industries. Based on the Routh-Hurwitz stability necessary and sufficient criteria, we establish several stability regions which enclose within them the P/PID parameter values that guarantee close-loop stability of the double-loop control scheme. A systematic tuning rule is developed for the purpose of obtaining the optimal P/PID parameter values within the established regions. The effectiveness of the proposed tuning rule is demonstrated using several numerical examples and the result are compared with some well-established tuning methods reported in the literature.

  10. Lateral instability of high temperature pipelines, the 20-in. Sleipner Vest pipeline

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Saevik, S.; Levold, E.; Johnsen, O.K.

    1996-12-01

    The present paper addresses methods to control snaking behavior of high temperature pipelines resting on a flat sea bed. A case study is presented based on the detail engineering of the 12.5 km long 20 inch gas pipeline connecting the Sleipner Vest wellhead platform to the Sleipner T processing platform in the North Sea. The study includes screening and evaluation of alternative expansion control methods, ending up with a recommended method. The methodology and philosophy, used as basis to ensure sufficient structural strength throughout the lifetime of the pipeline, are thereafter presented. The results show that in order to findmore » the optimum technical solution to control snaking behavior, many aspects need to be considered such as process requirements, allowable strain, hydrodynamic stability, vertical profile, pipelay installation and trawlboard loading. It is concluded that by proper consideration of all the above aspects, the high temperature pipeline can be designed to obtain sufficient safety level.« less

  11. Controllers, observers, and applications thereof

    NASA Technical Reports Server (NTRS)

    Gao, Zhiqiang (Inventor); Zhou, Wankun (Inventor); Miklosovic, Robert (Inventor); Radke, Aaron (Inventor); Zheng, Qing (Inventor)

    2011-01-01

    Controller scaling and parameterization are described. Techniques that can be improved by employing the scaling and parameterization include, but are not limited to, controller design, tuning and optimization. The scaling and parameterization methods described here apply to transfer function based controllers, including PID controllers. The parameterization methods also apply to state feedback and state observer based controllers, as well as linear active disturbance rejection (ADRC) controllers. Parameterization simplifies the use of ADRC. A discrete extended state observer (DESO) and a generalized extended state observer (GESO) are described. They improve the performance of the ESO and therefore ADRC. A tracking control algorithm is also described that improves the performance of the ADRC controller. A general algorithm is described for applying ADRC to multi-input multi-output systems. Several specific applications of the control systems and processes are disclosed.

  12. Improving Service Delivery in a County Health Department WIC Clinic: An Application of Statistical Process Control Techniques

    PubMed Central

    Boe, Debra Thingstad; Parsons, Helen

    2009-01-01

    Local public health agencies are challenged to continually improve service delivery, yet they frequently operate with constrained resources. Quality improvement methods and techniques such as statistical process control are commonly used in other industries, and they have recently been proposed as a means of improving service delivery and performance in public health settings. We analyzed a quality improvement project undertaken at a local Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinic to reduce waiting times and improve client satisfaction with a walk-in nutrition education service. We used statistical process control techniques to evaluate initial process performance, implement an intervention, and assess process improvements. We found that implementation of these techniques significantly reduced waiting time and improved clients' satisfaction with the WIC service. PMID:19608964

  13. Development and Validation of a UHPLC UV Method for the In-Process Control of Bosentan Monohydrate Synthesis.

    PubMed

    Jatczak, Marta; Sidoryk, Katarzyna; Kossykowska, Magdalena; Łuniewski, Wojciech; Zagrodzka, Joanna; Lipiec-Abramska, Elżbieta

    2016-01-01

    Bosentan monohydrate (4- tert -butyl- N -[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl) pyrimidin-4-yl]benzene-1-sulfonamide monohydrate) is a dual endothelin receptor antagonist (ERA) applied in the treatment of pulmonary arterial hypertension. To achieve effective process control of the bosentan monohydrate synthesis, it was necessary to develop a selective and not highly time-consuming method for ultra-high performance liquid chromatography (UHPLC). The method is characterized by adequate sensitivity, reproducibility and selectivity for the determination of bosentan monohydrate and related compounds from all synthetic stages. The UHPLC separation was carried out by reversed phase chromatography on the Acquity BEH C18 column (100 mm × 2.1 mm, 1.7 µm) with a mobile phase composed of solvent A (0.1 %, v/v, acetic acid in water) and solvent B (methanol), in the gradient mode at the flow rate of 0.4 mL min -1 . Limits of detection and quantification for the compounds were ≤0.1 µg mL -1 and 0.3 µg mL -1 , respectively. The linearity for all related compounds was investigated as in the range for the active pharmaceutical ingredient (API) and as in the range for the in-process control. The developed method was validated according to the current guidelines, proving the suitability of the method for its intended purpose.

  14. Common method biases in behavioral research: a critical review of the literature and recommended remedies.

    PubMed

    Podsakoff, Philip M; MacKenzie, Scott B; Lee, Jeong-Yeon; Podsakoff, Nathan P

    2003-10-01

    Interest in the problem of method biases has a long history in the behavioral sciences. Despite this, a comprehensive summary of the potential sources of method biases and how to control for them does not exist. Therefore, the purpose of this article is to examine the extent to which method biases influence behavioral research results, identify potential sources of method biases, discuss the cognitive processes through which method biases influence responses to measures, evaluate the many different procedural and statistical techniques that can be used to control method biases, and provide recommendations for how to select appropriate procedural and statistical remedies for different types of research settings.

  15. Implementation of Non-Destructive Evaluation and Process Monitoring in DLP-based Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Kovalenko, Iaroslav; Verron, Sylvain; Garan, Maryna; Šafka, Jiří; Moučka, Michal

    2017-04-01

    This article describes a method of in-situ process monitoring in the digital light processing (DLP) 3D printer. It is based on the continuous measurement of the adhesion force between printing surface and bottom of a liquid resin bath. This method is suitable only for the bottom-up DPL printers. Control system compares the force at the moment of unsticking of printed layer from the bottom of the tank, when it has the largest value in printing cycle, with theoretical value. Implementation of suggested algorithm can make detection of faults during the printing process possible.

  16. A Review of International Space Station Habitable Element Equipment Offgassing Characteristics

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.

    2010-01-01

    Crewed spacecraft trace contaminant control employs both passive and active methods to achieve acceptable cabin atmospheric quality. Passive methods include carefully selecting materials of construction, employing clean manufacturing practices, and minimizing systems and payload operational impacts to the cabin environment. Materials selection and manufacturing processes constitute the first level of equipment offgassing control. An element-level equipment offgassing test provides preflight verification that passive controls have been successful. Offgassing test results from multiple International Space Station (ISS) habitable elements and cargo vehicles are summarized and implications for active contamination control equipment design are discussed

  17. Learning from ISS-modular adaptive NN control of nonlinear strict-feedback systems.

    PubMed

    Wang, Cong; Wang, Min; Liu, Tengfei; Hill, David J

    2012-10-01

    This paper studies learning from adaptive neural control (ANC) for a class of nonlinear strict-feedback systems with unknown affine terms. To achieve the purpose of learning, a simple input-to-state stability (ISS) modular ANC method is first presented to ensure the boundedness of all the signals in the closed-loop system and the convergence of tracking errors in finite time. Subsequently, it is proven that learning with the proposed stable ISS-modular ANC can be achieved. The cascade structure and unknown affine terms of the considered systems make it very difficult to achieve learning using existing methods. To overcome these difficulties, the stable closed-loop system in the control process is decomposed into a series of linear time-varying (LTV) perturbed subsystems with the appropriate state transformation. Using a recursive design, the partial persistent excitation condition for the radial basis function neural network (NN) is established, which guarantees exponential stability of LTV perturbed subsystems. Consequently, accurate approximation of the closed-loop system dynamics is achieved in a local region along recurrent orbits of closed-loop signals, and learning is implemented during a closed-loop feedback control process. The learned knowledge is reused to achieve stability and an improved performance, thereby avoiding the tremendous repeated training process of NNs. Simulation studies are given to demonstrate the effectiveness of the proposed method.

  18. Micromechanical Devices for Control of Cell-Cell Interaction, and Methods of Use Thereof

    NASA Technical Reports Server (NTRS)

    Bhatia, Sangeeta N. (Inventor); Hui, Elliot (Inventor)

    2017-01-01

    The development and function of living tissues depends largely on interactions between cells that can vary in both time and space; however, temporal control of cell-cell interaction is experimentally challenging. By employing a micromachined silicon substrate with moving parts, herein is disclosed the dynamic regulation of cell-cell interactions via direct manipulation of adherent cells with micron-scale precision. The inventive devices and methods allow mechanical control of both tissue composition and spatial organization. The inventive device and methods enable the investigation of dynamic cell-cell interaction in a multitude of applications, such as intercellular communication, spanning embryogenesis, homeostasis, and pathogenic processes.

  19. Thermal energy storage apparatus, controllers and thermal energy storage control methods

    DOEpatents

    Hammerstrom, Donald J.

    2016-05-03

    Thermal energy storage apparatus, controllers and thermal energy storage control methods are described. According to one aspect, a thermal energy storage apparatus controller includes processing circuitry configured to access first information which is indicative of surpluses and deficiencies of electrical energy upon an electrical power system at a plurality of moments in time, access second information which is indicative of temperature of a thermal energy storage medium at a plurality of moments in time, and use the first and second information to control an amount of electrical energy which is utilized by a heating element to heat the thermal energy storage medium at a plurality of moments in time.

  20. A reinforcement learning-based architecture for fuzzy logic control

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1992-01-01

    This paper introduces a new method for learning to refine a rule-based fuzzy logic controller. A reinforcement learning technique is used in conjunction with a multilayer neural network model of a fuzzy controller. The approximate reasoning based intelligent control (ARIC) architecture proposed here learns by updating its prediction of the physical system's behavior and fine tunes a control knowledge base. Its theory is related to Sutton's temporal difference (TD) method. Because ARIC has the advantage of using the control knowledge of an experienced operator and fine tuning it through the process of learning, it learns faster than systems that train networks from scratch. The approach is applied to a cart-pole balancing system.

  1. On-Line Control of Glucose Concentration in High-Yielding Mammalian Cell Cultures Enabled Through Oxygen Transfer Rate Measurements.

    PubMed

    Goldrick, Stephen; Lee, Kenneth; Spencer, Christopher; Holmes, William; Kuiper, Marcel; Turner, Richard; Farid, Suzanne S

    2018-04-01

    Glucose control is vital to ensure consistent growth and protein production in mammalian cell cultures. The typical fed-batch glucose control strategy involving bolus glucose additions based on infrequent off-line daily samples results in cells experiencing significant glucose concentration fluctuations that can influence product quality and growth. This study proposes an on-line method to control and manipulate glucose utilizing readily available process measurements. The method generates a correlation between the cumulative oxygen transfer rate and the cumulative glucose consumed. This correlation generates an on-line prediction of glucose that has been successfully incorporated into a control algorithm manipulating the glucose feed-rate. This advanced process control (APC) strategy enables the glucose concentration to be maintained at an adjustable set-point and has been found to significantly reduce the deviation in glucose concentration in comparison to conventional operation. This method has been validated to produce various therapeutic proteins across cell lines with different glucose consumption demands and is successfully demonstrated on micro (15 mL), laboratory (7 L), and pilot (50 L) scale systems. This novel APC strategy is simple to implement and offers the potential to significantly enhance the glucose control strategy for scales spanning micro-scale systems through to full scale industrial bioreactors. © 2018 The Authors. Biotechnology Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  2. [Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry].

    PubMed

    Villani, N; Gérard, K; Marchesi, V; Huger, S; François, P; Noël, A

    2010-06-01

    The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (IMRT) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. At Alexis-Vautrin center, pretreatment quality controls in IMRT for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multileaf collimator). Correlation between dose measured at one point, given with the EPID and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. The study allowed to demonstrate the feasibility to reduce the time devoted to pretreatment controls, by substituting the ionisation chamber's measurements with those performed with EPID, and also that a statistical process control monitoring of data brought security guarantee. 2010 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  3. Low cost composite manufacturing utilizing intelligent pultrusion and resin transfer molding (IPRTM)

    NASA Astrophysics Data System (ADS)

    Bradley, James E.; Wysocki, Tadeusz S., Jr.

    1993-02-01

    This article describes an innovative method for the economical manufacturing of large, intricately-shaped tubular composite parts. Proprietary intelligent process control techniques are combined with standard pultrusion and RTM methodologies to provide high part throughput, performance, and quality while substantially reducing scrap, rework costs, and labor requirements. On-line process monitoring and control is achieved through a smart tooling interface consisting of modular zone tiles installed on part-specific die assemblies. Real-time archiving of process run parameters provides enhanced SPC and SQC capabilities.

  4. Manufacturing engineering: Principles for optimization

    NASA Astrophysics Data System (ADS)

    Koenig, Daniel T.

    Various subjects in the area of manufacturing engineering are addressed. The topics considered include: manufacturing engineering organization concepts and management techniques, factory capacity and loading techniques, capital equipment programs, machine tool and equipment selection and implementation, producibility engineering, methods, planning and work management, and process control engineering in job shops. Also discussed are: maintenance engineering, numerical control of machine tools, fundamentals of computer-aided design/computer-aided manufacture, computer-aided process planning and data collection, group technology basis for plant layout, environmental control and safety, and the Integrated Productivity Improvement Program.

  5. Infrared and Raman spectroscopic methods for characterization of Taxus baccata L.--Improved taxane isolation by accelerated quality control and process surveillance.

    PubMed

    Gudi, Gennadi; Krähmer, Andrea; Koudous, Iraj; Strube, Jochen; Schulz, Hartwig

    2015-10-01

    Different yew species contain poisonous taxane alkaloids which serve as resources for semi-synthesis of anticancer drugs. The highly variable amounts of taxanes demand new methods for fast characterization of the raw plant material and the isolation of the target structures during phyto extraction. For that purpose, applicability of different vibrational spectroscopy methods in goods receipt of raw plant material and in process control was investigated and demonstrated in online tracking isolation and purification of the target taxane 10-deacetylbaccatin III (10-DAB) during solvent extraction. Applying near (NIRS) and mid infrared spectroscopy (IRS) the amount of botanical impurities in mixed samples of two different yew species (R(2)=0.993), the leave-to-wood ratio for Taxus baccata material (R(2)=0.94) and moisture in dried yew needles (R(2)=0.997) can be quantified. By partial least square analysis (PCA) needles of different Coniferales species were successfully discriminated by Attenuated Total Reflectance-Fourier-Transform Infrared Spectroscopy (ATR-FT-IR). The analytical potential of ATR-FT-IR and Fourier Transform-Raman Spectroscopy (FT-RS) in process control of extraction and purification of taxanes is demonstrated for determination of the water content in methanolic yew extracts (R(2)=0.999) and for quantification of 10-DAB (R(2)=0.98) on a highly sophisticated level. The decrease of 10-DAB in the plant tissue during extraction was successfully visualized by FT-IR imaging of thin cross sections providing new perspectives for process control and design. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Can we (control) Engineer the degree learning process?

    NASA Astrophysics Data System (ADS)

    White, A. S.; Censlive, M.; Neilsen, D.

    2014-07-01

    This paper investigates how control theory could be applied to learning processes in engineering education. The initial point for the analysis is White's Double Loop learning model of human automation control modified for the education process where a set of governing principals is chosen, probably by the course designer. After initial training the student decides unknowingly on a mental map or model. After observing how the real world is behaving, a strategy to achieve the governing variables is chosen and a set of actions chosen. This may not be a conscious operation, it maybe completely instinctive. These actions will cause some consequences but not until a certain time delay. The current model is compared with the work of Hollenbeck on goal setting, Nelson's model of self-regulation and that of Abdulwahed, Nagy and Blanchard at Loughborough who investigated control methods applied to the learning process.

  7. Phase formation polycrystalline vanadium oxide via thermal annealing process under controlled nitrogen pressure

    NASA Astrophysics Data System (ADS)

    Jessadaluk, S.; Khemasiri, N.; Rahong, S.; Rangkasikorn, A.; Kayunkid, N.; Wirunchit, S.; Horprathum, M.; Chananonnawathron, C.; Klamchuen, A.; Nukeaw, J.

    2017-09-01

    This article provides an approach to improve and control crystal phases of the sputtering vanadium oxide (VxOy) thin films by post-thermal annealing process. Usually, as-deposited VxOy thin films at room temperature are amorphous phase: post-thermal annealing processes (400 °C, 2 hrs) under the various nitrogen (N2) pressures are applied to improve and control the crystal phase of VxOy thin films. The crystallinity of VxOy thin films changes from amorphous to α-V2O5 phase or V9O17 polycrystalline, which depend on the pressure of N2 carrier during annealing process. Moreover, the electrical resistivity of the VxOy thin films decrease from 105 Ω cm (amorphous) to 6×10-1 Ω cm (V9O17). Base on the results, our study show a simply method to improve and control phase formation of VxOy thin films.

  8. PID Tuning Using Extremum Seeking

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Killingsworth, N; Krstic, M

    2005-11-15

    Although proportional-integral-derivative (PID) controllers are widely used in the process industry, their effectiveness is often limited due to poor tuning. Manual tuning of PID controllers, which requires optimization of three parameters, is a time-consuming task. To remedy this difficulty, much effort has been invested in developing systematic tuning methods. Many of these methods rely on knowledge of the plant model or require special experiments to identify a suitable plant model. Reviews of these methods are given in [1] and the survey paper [2]. However, in many situations a plant model is not known, and it is not desirable to openmore » the process loop for system identification. Thus a method for tuning PID parameters within a closed-loop setting is advantageous. In relay feedback tuning [3]-[5], the feedback controller is temporarily replaced by a relay. Relay feedback causes most systems to oscillate, thus determining one point on the Nyquist diagram. Based on the location of this point, PID parameters can be chosen to give the closed-loop system a desired phase and gain margin. An alternative tuning method, which does not require either a modification of the system or a system model, is unfalsified control [6], [7]. This method uses input-output data to determine whether a set of PID parameters meets performance specifications. An adaptive algorithm is used to update the PID controller based on whether or not the controller falsifies a given criterion. The method requires a finite set of candidate PID controllers that must be initially specified [6]. Unfalsified control for an infinite set of PID controllers has been developed in [7]; this approach requires a carefully chosen input signal [8]. Yet another model-free PID tuning method that does not require opening of the loop is iterative feedback tuning (IFT). IFT iteratively optimizes the controller parameters with respect to a cost function derived from the output signal of the closed-loop system, see [9]. This method is based on the performance of the closed-loop system during a step response experiment [10], [11]. In this article we present a method for optimizing the step response of a closed-loop system consisting of a PID controller and an unknown plant with a discrete version of extremum seeking (ES). Specifically, ES is used to minimize a cost function similar to that used in [10], [11], which quantifies the performance of the PID controller. ES, a non-model-based method, iteratively modifies the arguments (in this application the PID parameters) of a cost function so that the output of the cost function reaches a local minimum or local maximum. In the next section we apply ES to PID controller tuning. We illustrate this technique through simulations comparing the effectiveness of ES to other PID tuning methods. Next, we address the importance of the choice of cost function and consider the effect of controller saturation. Furthermore, we discuss the choice of ES tuning parameters. Finally, we offer some conclusions.« less

  9. Free suspension processing of oxides to form amorphous oxide materials, appendix B

    NASA Technical Reports Server (NTRS)

    Wouch, G.

    1973-01-01

    The processing of yttria, zirconia, and alumina under weightless conditions is discussed. The process consists of levitation or position control, heating and melting, superheating, and supercooling. The use of arc imaging furnaces, lasers, induction heating, microwave, and electron beam methods are analyzed to show the advantages and disadvantages of each.

  10. Imagery and Verbal Counseling Methods in Stress Inoculation Training for Pain Control.

    ERIC Educational Resources Information Center

    Worthington, Everett L., Jr.; Shumate, Michael

    1981-01-01

    Pleasant imagery relieves pain and may account for much of the effectiveness of stress inoculation training. Women who used imagery controlled their pain better; women who did not use imagery had longer tolerance when they heard pain conceptualized as a multistage process. Self-instruction did not affect pain control. (Author)

  11. PSO-tuned PID controller for coupled tank system via priority-based fitness scheme

    NASA Astrophysics Data System (ADS)

    Jaafar, Hazriq Izzuan; Hussien, Sharifah Yuslinda Syed; Selamat, Nur Asmiza; Abidin, Amar Faiz Zainal; Aras, Mohd Shahrieel Mohd; Nasir, Mohamad Na'im Mohd; Bohari, Zul Hasrizal

    2015-05-01

    The industrial applications of Coupled Tank System (CTS) are widely used especially in chemical process industries. The overall process is require liquids to be pumped, stored in the tank and pumped again to another tank. Nevertheless, the level of liquid in tank need to be controlled and flow between two tanks must be regulated. This paper presents development of an optimal PID controller for controlling the desired liquid level of the CTS. Two method of Particle Swarm Optimization (PSO) algorithm will be tested in optimizing the PID controller parameters. These two methods of PSO are standard Particle Swarm Optimization (PSO) and Priority-based Fitness Scheme in Particle Swarm Optimization (PFPSO). Simulation is conducted within Matlab environment to verify the performance of the system in terms of settling time (Ts), steady state error (SSE) and overshoot (OS). It has been demonstrated that implementation of PSO via Priority-based Fitness Scheme (PFPSO) for this system is potential technique to control the desired liquid level and improve the system performances compared with standard PSO.

  12. High-resolution frequency measurement method with a wide-frequency range based on a quantized phase step law.

    PubMed

    Du, Baoqiang; Dong, Shaofeng; Wang, Yanfeng; Guo, Shuting; Cao, Lingzhi; Zhou, Wei; Zuo, Yandi; Liu, Dan

    2013-11-01

    A wide-frequency and high-resolution frequency measurement method based on the quantized phase step law is presented in this paper. Utilizing a variation law of the phase differences, the direct different frequency phase processing, and the phase group synchronization phenomenon, combining an A/D converter and the adaptive phase shifting principle, a counter gate is established in the phase coincidences at one-group intervals, which eliminates the ±1 counter error in the traditional frequency measurement method. More importantly, the direct phase comparison, the measurement, and the control between any periodic signals have been realized without frequency normalization in this method. Experimental results show that sub-picosecond resolution can be easily obtained in the frequency measurement, the frequency standard comparison, and the phase-locked control based on the phase quantization processing technique. The method may be widely used in navigation positioning, space techniques, communication, radar, astronomy, atomic frequency standards, and other high-tech fields.

  13. Gr-GDHP: A New Architecture for Globalized Dual Heuristic Dynamic Programming.

    PubMed

    Zhong, Xiangnan; Ni, Zhen; He, Haibo

    2017-10-01

    Goal representation globalized dual heuristic dynamic programming (Gr-GDHP) method is proposed in this paper. A goal neural network is integrated into the traditional GDHP method providing an internal reinforcement signal and its derivatives to help the control and learning process. From the proposed architecture, it is shown that the obtained internal reinforcement signal and its derivatives can be able to adjust themselves online over time rather than a fixed or predefined function in literature. Furthermore, the obtained derivatives can directly contribute to the objective function of the critic network, whose learning process is thus simplified. Numerical simulation studies are applied to show the performance of the proposed Gr-GDHP method and compare the results with other existing adaptive dynamic programming designs. We also investigate this method on a ball-and-beam balancing system. The statistical simulation results are presented for both the Gr-GDHP and the GDHP methods to demonstrate the improved learning and controlling performance.

  14. A Simple and Direct LC-MS Method for Determination of Genotoxic Impurity Hydroxylamine in Pharmaceutical compounds.

    PubMed

    Kumar, Thangarathinam; Ramya, Mohandass; Srinivasan, Viswanathan; Xavier, N

    2017-08-01

    Hydroxylamine is a known genotoxic impurity compound that needs to be controlled down to ppm level in pharmaceutical processes. It is difficult to detect using conventional analytical techniques due to its physio-chemical properties like lack of chromophore, low molecular weight, absence of carbon atom and high polarity. In addition to that, analysis of the pharmaceutical samples encounters considerable obstruction from matrix components that greatly overshadow the response of hydroxylamine. This study describes a simple, sensitive and direct Liquid Chromatographic-Mass Spectrometric method (LC-MS) for detection of hydroxylamine in pharmaceutical compounds. The LC-MS method was detected up to 0.008 ppm of hydroxylamine with S/N > 3.0 and quantified up to 0.025 ppm of hydroxylamine with S/N ratio >10.0. This validated method can be applied as a generic method to detect the hydroxylamine for pharmaceutical process control and drug substance release. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Closed loop statistical performance analysis of N-K knock controllers

    NASA Astrophysics Data System (ADS)

    Peyton Jones, James C.; Shayestehmanesh, Saeed; Frey, Jesse

    2017-09-01

    The closed loop performance of engine knock controllers cannot be rigorously assessed from single experiments or simulations because knock behaves as a random process and therefore the response belongs to a random distribution also. In this work a new method is proposed for computing the distributions and expected values of the closed loop response, both in steady state and in response to disturbances. The method takes as its input the control law, and the knock propensity characteristic of the engine which is mapped from open loop steady state tests. The method is applicable to the 'n-k' class of knock controllers in which the control action is a function only of the number of cycles n since the last control move, and the number k of knock events that have occurred in this time. A Cumulative Summation (CumSum) based controller falls within this category, and the method is used to investigate the performance of the controller in a deeper and more rigorous way than has previously been possible. The results are validated using onerous Monte Carlo simulations, which confirm both the validity of the method and its high computational efficiency.

  16. A Model of Risk Analysis in Analytical Methodology for Biopharmaceutical Quality Control.

    PubMed

    Andrade, Cleyton Lage; Herrera, Miguel Angel De La O; Lemes, Elezer Monte Blanco

    2018-01-01

    One key quality control parameter for biopharmaceutical products is the analysis of residual cellular DNA. To determine small amounts of DNA (around 100 pg) that may be in a biologically derived drug substance, an analytical method should be sensitive, robust, reliable, and accurate. In principle, three techniques have the ability to measure residual cellular DNA: radioactive dot-blot, a type of hybridization; threshold analysis; and quantitative polymerase chain reaction. Quality risk management is a systematic process for evaluating, controlling, and reporting of risks that may affects method capabilities and supports a scientific and practical approach to decision making. This paper evaluates, by quality risk management, an alternative approach to assessing the performance risks associated with quality control methods used with biopharmaceuticals, using the tool hazard analysis and critical control points. This tool provides the possibility to find the steps in an analytical procedure with higher impact on method performance. By applying these principles to DNA analysis methods, we conclude that the radioactive dot-blot assay has the largest number of critical control points, followed by quantitative polymerase chain reaction, and threshold analysis. From the analysis of hazards (i.e., points of method failure) and the associated method procedure critical control points, we conclude that the analytical methodology with the lowest risk for performance failure for residual cellular DNA testing is quantitative polymerase chain reaction. LAY ABSTRACT: In order to mitigate the risk of adverse events by residual cellular DNA that is not completely cleared from downstream production processes, regulatory agencies have required the industry to guarantee a very low level of DNA in biologically derived pharmaceutical products. The technique historically used was radioactive blot hybridization. However, the technique is a challenging method to implement in a quality control laboratory: It is laborious, time consuming, semi-quantitative, and requires a radioisotope. Along with dot-blot hybridization, two alternatives techniques were evaluated: threshold analysis and quantitative polymerase chain reaction. Quality risk management tools were applied to compare the techniques, taking into account the uncertainties, the possibility of circumstances or future events, and their effects upon method performance. By illustrating the application of these tools with DNA methods, we provide an example of how they can be used to support a scientific and practical approach to decision making and can assess and manage method performance risk using such tools. This paper discusses, considering the principles of quality risk management, an additional approach to the development and selection of analytical quality control methods using the risk analysis tool hazard analysis and critical control points. This tool provides the possibility to find the method procedural steps with higher impact on method reliability (called critical control points). Our model concluded that the radioactive dot-blot assay has the larger number of critical control points, followed by quantitative polymerase chain reaction and threshold analysis. Quantitative polymerase chain reaction is shown to be the better alternative analytical methodology in residual cellular DNA analysis. © PDA, Inc. 2018.

  17. Method of transition from 3D model to its ontological representation in aircraft design process

    NASA Astrophysics Data System (ADS)

    Govorkov, A. S.; Zhilyaev, A. S.; Fokin, I. V.

    2018-05-01

    This paper proposes the method of transition from a 3D model to its ontological representation and describes its usage in the aircraft design process. The problems of design for manufacturability and design automation are also discussed. The introduced method is to aim to ease the process of data exchange between important aircraft design phases, namely engineering and design control. The method is also intended to increase design speed and 3D model customizability. This requires careful selection of the complex systems (CAD / CAM / CAE / PDM), providing the basis for the integration of design and technological preparation of production and more fully take into account the characteristics of products and processes for their manufacture. It is important to solve this problem, as investment in the automation define the company's competitiveness in the years ahead.

  18. Validation Methods for Fault-Tolerant avionics and control systems, working group meeting 1

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The proceedings of the first working group meeting on validation methods for fault tolerant computer design are presented. The state of the art in fault tolerant computer validation was examined in order to provide a framework for future discussions concerning research issues for the validation of fault tolerant avionics and flight control systems. The development of positions concerning critical aspects of the validation process are given.

  19. The efficacy of a continuous quality improvement (CQI) method in a radiological department. Comparison with non-CQI control material.

    PubMed

    Laurila, J; Standertskjöld-Nordenstam, C G; Suramo, I; Tolppanen, E M; Tervonen, O; Korhola, O; Brommels, M

    2001-01-01

    To study the efficacy of continuous quality improvement (CQI) compared to ordinary management in an on-duty radiology department. Because of complaints regarding delivery of on-duty radiological services, an improvement was initiated simultaneously at two hospitals, at the HUCH (Helsinki University Central Hospital) utilising the CQI-method, and at the OUH (Oulu University Hospital) with a traditional management process. For the CQI project, a team was formed to evaluate the process with flow-charts, cause and effect diagrams, Pareto analysis and control charts. Interventions to improve the process were based on the results of these analyses. The team at the HUCH implemented the following changes: A radiologist was added to the evening shift between 15:00-22:00 and a radiographer was moved from the morning shift to 15:00-22:00. A clear improvement was achieved in the turn-around time, but in the follow-up some of the gains were lost. Only minimal changes were achieved at the OUH, where the intervention was based on traditional management processes. CQI was an effective method for improving the quality of performance of a radiology department compared with ordinary management methods, but some of this improvement may be subsequently lost without a continuous measurement system.

  20. Qualitative research methods: key features and insights gained from use in infection prevention research.

    PubMed

    Forman, Jane; Creswell, John W; Damschroder, Laura; Kowalski, Christine P; Krein, Sarah L

    2008-12-01

    Infection control professionals and hospital epidemiologists are accustomed to using quantitative research. Although quantitative studies are extremely important in the field of infection control and prevention, often they cannot help us explain why certain factors affect the use of infection control practices and identify the underlying mechanisms through which they do so. Qualitative research methods, which use open-ended techniques, such as interviews, to collect data and nonstatistical techniques to analyze it, provide detailed, diverse insights of individuals, useful quotes that bring a realism to applied research, and information about how different health care settings operate. Qualitative research can illuminate the processes underlying statistical correlations, inform the development of interventions, and show how interventions work to produce observed outcomes. This article describes the key features of qualitative research and the advantages that such features add to existing quantitative research approaches in the study of infection control. We address the goal of qualitative research, the nature of the research process, sampling, data collection and analysis, validity, generalizability of findings, and presentation of findings. Health services researchers are increasingly using qualitative methods to address practical problems by uncovering interacting influences in complex health care environments. Qualitative research methods, applied with expertise and rigor, can contribute important insights to infection prevention efforts.

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