WorldWideScience
 
 
1

Geotail MCA plasma wave data analysis  

Science.gov (United States)

NASA Grant NAG 5-2346 supports the data analysis effort at The University of Iowa for the GEOTAIL Multi-Channel Analyzer (MCA) which is a part of the GEOTAIL Plasma Wave Instrument (PWI). At the beginning of this reporting period we had just begun to receive our GEOTAIL Sirius data on CD-ROMs. Much programming effort went into adapting and refining the data analysis programs to include the CD-ROM inputs. Programs were also developed to display the high-frequency-resolution PWI Sweep Frequency Analyzer (SFA) data and to include in all the various plot products the electron cyclotron frequency derived from the magnitude of the magnetic field extracted from the GEOTAIL Magnetic Field (MGF) data included in the GEOTAIL Sirius data. We also developed programs to use the MGF data residing in the Institute of Space and Astronautical Science (ISAS) GEOTAIL Scientific Data Base (SDB). Our programmers also developed programs and provided technical support for the GEOTAIL data analysis efforts of Co-lnvestigator William W. L. Taylor at Nichols Research Corporation (NRC). At the end of this report we have included brief summaries of the NRC effort and the progress being made.

Anderson, Roger R.

1994-01-01

2

Geotail MCA plasma wave data analysis  

Science.gov (United States)

NASA Grant NAG 5-2346 supports the data analysis effort at The University of Iowa for the GEOTAIL Multi-Channel Analyzer (MCA) which is a part of the GEOTAIL Plasma Wave Instrument (PWI). At the beginning of this reporting period we had just begun to receive our GEOTAIL Sirius data on CD-ROMs. Much programming effort went into adapting and refining the data analysis programs to include the CD-ROM inputs. Programs were also developed to display the high-frequency-resolution PWI Sweep Frequency Analyzer (SFA) data and to include in all the various plot products the electron cyclotron frequency derived from the magnitude of the magnetic field extracted from the GEOTAIL Magnetic Field (MGF) data included in the GEOTAIL Sirius data. We also developed programs to use the MGF data residing in the Institute of Space and Astronautical Science (ISAS) GEOTAIL Scientific Data Base (SDB). Our programmers also developed programs and provided technical support for the GEOTAIL data analysis efforts of Co-lnvestigator William W. L. Taylor at Nichols Research Corporation (NRC). At the end of this report we have included brief summaries of the NRC effort and the progress being made.

Anderson, Roger R.

3

Dual function of the McaS small RNA in controlling biofilm formation : Genes Dev  

DEFF Research Database (Denmark)

Many bacterial small RNAs (sRNAs) regulate gene expression through base-pairing with mRNAs, and it has been assumed that these sRNAs act solely by this one mechanism. Here we report that the multicellular adhesive (McaS) sRNA of Escherichia coli uniquely acts by two different mechanisms: base-pairing and protein titration. Previous work established that McaS base pairs with the mRNAs encoding master transcription regulators of curli and flagella synthesis, respectively, resulting in down-regulation and up-regulation of these important cell surface structures. In this study, we demonstrate that McaS activates synthesis of the exopolysaccharide beta-1,6 N-acetyl-D-glucosamine (PGA) by binding the global RNA-binding protein CsrA, a negative regulator of pgaA translation. The McaS RNA bears at least two CsrA-binding sequences, and inactivation of these sites compromises CsrA binding, PGA regulation, and biofilm formation. Moreover, ectopic McaS expression leads to induction of two additional CsrA-repressed genes encoding diguanylate cyclases. Collectively, our study shows that McaS is a dual-function sRNA with roles in the two major post-transcriptional regulons controlled by the RNA-binding proteins Hfq and CsrA.

JØrgensen, Mikkel Girke; Thomason, Maureen K.

2013-01-01

4

Flow Injection Analysis and Liquid Chromatography for Multifunctional Chemical Analysis (MCA) Systems  

Science.gov (United States)

The large class sizes of first-year chemistry labs makes it challenging to provide students with hands-on access to instrumentation because the number of students typically far exceeds the number of research-grade instruments available to collect data. Multifunctional chemical analysis (MCA) systems provide a viable alternative for large-scale…

Mayo, Ana V.; Loegel, Thomas N.; Bretz, Stacey Lowery; Danielson, Neil D.

2013-01-01

5

Design and implementation of an MCA card with double ADC for nuclear radiation analysis  

International Nuclear Information System (INIS)

The rapid development of technology has triggered several interesting trends in nuclear instrumentation. In particular, the introduction of add-on cards that can serve as multichannel analyzer and offer adequate performance for most of the nuclear applications. The purpose of this thesis has been the design of a multichannel analyser inserted into microcomputer. The originality of this prototype MCA card with its innovative concept is the use of two analog digital converters or ADC of which the objective is to reduce to minima the lost of pulses during the acquisition and the signals processing. The first ADC works as the main converter (or master) and the second ADC the slave converter. The first ADC begins the first signals acquisition, while it will be busy for the processing, the second ADC continues the acquisition, thus there will be no lost pulses or precisely lost of pulses will be reduced to minima.The three main points for a multichannel analyzer will be studied such a the pile-up, the differential non-linearity or 'DNL' and the dead time. In the first part of this thesis the function of the MCA has been described and the different roles of the composed modules have been developed. In the second part, spectra analysis has been done with the MCA prototype as well the comparison with other MCAs such as MCAs S100, TISA, MCA35+, and the Inspector.

6

Performance analysis of gamma ray spectrometric parameters on digital signal and analog signal processing based MCA systems using NaI(Tl) detector  

Energy Technology Data Exchange (ETDEWEB)

Accurate and speedy estimations of ppm range uranium and thorium in the geological and rock samples are most useful towards ongoing uranium investigations and identification of favorable radioactive zones in the exploration field areas. In this study with the existing 5 in. Multiplication-Sign 4 in. NaI(Tl) detector setup, prevailing background and time constraints, an enhanced geometrical setup has been worked out to improve the minimum detection limits for primordial radioelements K{sup 40}, U{sup 238} and Th{sup 232}. This geometrical setup has been integrated with the newly introduced, digital signal processing based MCA system for the routine spectrometric analysis of low concentration rock samples. Stability performance, during the long counting hours, for digital signal processing MCA system and its predecessor NIM bin based MCA system has been monitored, using the concept of statistical process control. Monitored results, over a time span of few months, have been quantified in terms of spectrometer's parameters such as Compton striping constants and Channel sensitivities, used for evaluating primordial radio element concentrations (K{sup 40}, U{sup 238} and Th{sup 232}) in geological samples. Results indicate stable dMCA performance, with a tendency of higher relative variance, about mean, particularly for Compton stripping constants. - Highlights: Black-Right-Pointing-Pointer Geometrical enhancement for ppm range primordial radio elemental determination. Black-Right-Pointing-Pointer Experimental constraints include detector setup, background and counting time. Black-Right-Pointing-Pointer Gamma spectrometric performance monitored on digital and analog MCA systems. Black-Right-Pointing-Pointer Study indicates higher variance of Compton stripping constants on digital MCA system.

Kukreti, B.M., E-mail: bharatkuk@gmail.com [Atomic Minerals Directorate for Exploration and Research, Physics Laboratory, Department of Atomic Energy, Nongmynsong, AMD Complex, Shillong, Meghalaya 793019 (India); Sharma, G.K. [Atomic Minerals Directorate for Exploration and Research, Physics Laboratory, Department of Atomic Energy, Nongmynsong, AMD Complex, Shillong, Meghalaya 793019 (India)

2012-05-15

7

Use of multi-criteria analysis (MCA for supporting community forest management  

Directory of Open Access Journals (Sweden)

Full Text Available Sustainable forest management usually involves the use of criteria and indicators (C&I allowing the monitoring, reporting and assessment of management activities at national, regional and forest management unit levels. Experiences of such concepts are scarce in Nepal, particularly with regard to the evaluation of management activities within a Multi-Criteria Analysis (MCA framework. In this contribution we describe how a MCA approach can be used to efficiently exploit information, knowledge, and preferences of stakeholders to address community forest management problems. Beside rating and ranking techniques, the Analytic Hierarchy Process (AHP is used to examine the importance of six criteria and forty-four indicators in a sustainable forest management context with a broad range of stakeholder groups. An evaluation of four management strategies in the Shree Gyneshwar community forest user group allows to demonstrate the relevance of changing priorities for different criteria. A passive adaptive management strategy focusing on a multiple use of natural resources and the introduction of production-oriented measures were identified as the most preferable option. The results of this study show that the multi-criteria analysis approach, and in particular the AHP, can assist decision-makers in efficiently evaluating management problems and generating ideas for the long-term strategic planning process of community forest management, even under complex socio-economic and ecological conditions. In that context, compromise solutions enjoy a higher possibility of being successful, taking into account the different views of stakeholder groups.

Khadka C

2012-04-01

8

Development of 8K-MCA Add-on based on FPGA technique with a control of VB6 software application under windows environment  

International Nuclear Information System (INIS)

The multichannel analyzer is the heart of most experimental measurements. Today, it becomes popular and convenient. It can play a role of getting, processing data and easily interfacing to PC. Some standard-alone multichannel analysis systems can be replaced by Add-on MCA card. Especially, MCA card is necessary for application in nuclear physics research. The main aim of this sub-project is to focus on a design and construction of an 8K-MCA Add-on served for studying nuclear structure, for development of Gamma spectroscopy system, and for a production of low-cost electronics instruments as well. Some experimental results were obtained through the aforementioned card combining with other needed functional analog units. A multichannel data processing (MCD) circuit for nuclear spectroscopy application was developed using a field programmable gate arrays (FPGA) as the central processing element. In addition to the first role, A 13-bit analog-to-digital converter (8k ADC) circuit for nuclear spectroscopy application was also developed using a successive approximation ADC with a control of FPGA technology. The FPGA operates a program that builds the distributed functions of data collected by the ADC and then corrects the ADC differential non-linearity (DNL) via the sliding scale method. The acquisition routine runs in 3.7? s. the conversion time is approximated 2.2? s, and the integral non-linearity ? 0.14%. (author)

9

Determination of Steady-State and Faulty Regimes of Overhead Lines by Means of Multiconductor Cell Analysis (MCA  

Directory of Open Access Journals (Sweden)

Full Text Available Single-phase positive sequence modelling is often used in power systems when power flows and short circuit analysis are assessed. Of course, the use of single-phase positive sequence modelling assumes purely three-phase configurations and perfectly symmetrical ones so that single-phase modelling considers that all the phase conductors behave in the same way. When considering the physical reality of power networks, this assumption can be questionable and the behaviors of all the system conductors including the passive ones (earth wires for overhead lines, metallic screens and armours for cables and enclosures for gas insulated lines is completely unknown. Therefore, the present multiconductor cell analysis (MCA becomes necessary, since it allows one to achieve great precision results on the regimes of both phase conductors and passive conductors. MCA offers a powerful tool in order to validate (or less approximated and simplified computation methods. In particular, for single and double circuit overhead lines (OHLs, the current phasors induced in the earth wires and the ground return current alongside the line can be directly computed by MCA in steady state and faulty regimes. It is worth noting that, for faulty regimes, MCA allows also evaluating the approximation degree and validity field of screening factors k.

Fabio Guglielmi

2012-07-01

10

System of accounting and control of nuclear materials (MCA) relative to IAEA safeguards and improvement of radioecological situation of the Joint Stock Company ULBA Metallurgical Plant  

International Nuclear Information System (INIS)

Following goals must be accomplished following this Project : - Develop computerized and automated MCA data system; - Provide up-to-date and reliable accounting and control of availability and transfer of nuclear materials, detect loss or theft of nuclear materials; - Improve book keeping of nuclear materials, provide paperwork for raw materials and finished products sales and purchase control, process nuclear materials shipment data; - Reduce sampling error and to obtain precise measure of nuclear materials to obtain ESADRA target values; - Thorium concentrates transfer preliminary released from raw Beryllium to the new storage to prevent environment radiation pollution and obvious fire accidents; - Improve radioecological situation of the territory caused by old storage dismantling and decontamination of site; - Improve accounting, storing and Physical Protection of Thorium Following is the proposal to obtain goals of the Project : - Develop accounting and control systems - Develop basic standards and procedures for MCA system - Develop users specifications of MCA data system - Develop software of MCA data system - Assembly and adjustment of local network at the production facilities - Automated MCA data system personnel training - Develop measurement system - Determination of the mistakes in sampling and measurement of Uranium and isotopes content - Develop the procedures of sampling and measurement of Uranium and isotopes content providing ESADRA target values - Develop measure control program covering scales and analytical equipment and measuring methods - Develop software for measure control program support - Thorium shipment, decontamination and improvement of Physical Protection of Thorium storage - Accounting of Thorium containing materials when transferring to the new storage - Arrange storage decontamination - Develop new systems of Thorium Containment/Surveillance and Physical Protection

11

Material control and accountability (MC&A) recovery from the Cerro Grande fire at Los Alamos National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

During the week of May 10-14, 2000, the Cerro Grande Fire scorched over 40,000 acres of prime forestland and destroyed over 400 homes in the Los Alamos community and several structures at the Los Alamos National Laboratory (LANL). Of the land affected by the fire, nearly one quarter of it was Laboratory property. All of LANL's 64 material balance areas (MBAs) were affected to some degree, but one Category I technical area and several Category I11 and IV areas sustained heavy damage. When the MC&A personnel were allowed to return to work on May 23, they addressed the following problems: How do we assure both ourselves and the Department of Energy (DOE) that no nuclear materials had been compromised? How do we assist the nuclear material (NM) custodians and their operating groups so that they can resume normal MC&A operations? Immediately after the return to work, the Laboratory issued emergency MC&A assurance actions for Category I through Category IV facilities. We conducted special inventories, area walkthroughs, and other forms of evaluation so that within a month after the fire, we were able to release the last MBA to resume work and assure that all nuclear material had been accounted for. This paper discusses the measures LANL adopted to ensure that none of its nuclear material had been compromised.

Haag, William Earl

2001-01-01

12

NTS MC&A History  

Energy Technology Data Exchange (ETDEWEB)

Within the past three and a half years, the Nevada Test Site (NTS) has progressed from a Category IV to a Category I nuclear material facility. In accordance with direction from the U.S. Department of Energy (DOE) Secretary and National Nuclear Security Administration (NNSA) Administrator, NTS received shipments of large quantities of special nuclear material from Los Alamos National Laboratory (LANL) and other sites in the DOE complex. December 2004 was the first occurrence of Category I material at the NTS, with the exception of two weeks of sub-critical underground testing in 2001, since 1992. The Material Control and Accountability (MC&A) program was originally a jointlab effort by LANL, Lawrence Livermore National Laboratory, and Bechtel Nevada, but in March 2006 the NNSA Nevada Site Office appointed the NTS Management and Operations contractor with sole responsibility. This paper will discuss the process and steps taken to transition the NTS MC&A program from multiple organizations to a single entity and from a Category IV to a Category I program. This transition flourished as MC&A progressed from the 2004 Office of Assessment (OA) rating of “Significant Weakness” to the 2007 OA assessment rating of “Effective Performance.” The paper will provide timelines, funding and staffing issues, OA assessment findings and corrective actions, and future expectations. The process has been challenging, but MC&A’s innovative responses to the challenges have been very successful.

Mary Alice Price; Kim Young

2008-07-01

13

Assessment of Cerebrovascular Reserve before and after STA-MCA Bypass Surgery by SPECT and SPM Analysis  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to objectively assess the efficacy of superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery using Technetium (Tc)-99m-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) in patients who underwent STA-MCA bypass surgery. Brain perfusion SPECT images obtained at baseline and after the administration of acetazolamide were reconstructed using statistical parametric mapping in 23 patients, both before and after STA-MCA bypass surgery. The clinical outcomes of the surgery were also recorded and compared with the hemodynamic changes. A voxel with an uncorrected p-value of less than 0.001 was considered to be statistically significant. SPECT images of the territory supplied by the bypass graft showed an increase in both cerebrovascular flow and reserve at baseline, and the increase was significantly higher following the administration of acetazolamide. All patients showed improvement of clinical symptoms and increased blood flow to the left temporal, parietal, and frontal cortices as well as the thalamus. Brain SPECT effectively and objectively demonstrated the improved outcomes of STA-MCA bypass surgery, and thus may be used in postoperative analyses.

O, Joo-Hyun; Jang, Kyung-Sool; Yoo, Ie-Ryung [The Catholic University of Korea, Seoul (Korea, Republic of)] (and others)

2007-12-15

14

Haemodynamic analysis of vessel remodelling in STA-MCA bypass for Moyamoya disease and its impact on bypass patency.  

Science.gov (United States)

The purpose of this study is to estimate the remodelling characteristics of STA-MCA bypass and its influence on patency via the use of computational fluid dynamic (CFD) technology. The reconstructed three-dimensional geometries from MRA were segmented to create computational domains for CFD simulations. Eleven patients, who underwent regular MRA both immediately following surgery and at the six months follow-up, were studied. The flow velocities at STA were measured via the use of quantitative MRA (QMRA) to validate simulation results. STA-MCA bypass patency was confirmed for each patient immediately following surgery. The simulation indicated that the remodelling of the arterial pedicle in nine patients was associated with a reduction in the resistance to flow through the bypass. For these cases, the modelling of a driving pressure of 10mmHg through the bypass at 6 months post-surgery resulted in a 50% greater blood flow than those found immediately following surgery. However, two patients were found to exhibit contradictory patterns of remodelling, in which a highly curved bending at the bypass immediately post-surgery underwent progression, with increased resistance to flow through the bypass at 6 months follow-up, thereby resulting in a modelled flow rate reduction of 50% and 25%, respectively. This study revealed that STA-MCA bypass has a characteristic remodelling that usually reduces flow resistance. The initial morphology of the bypass may have had a significant effect on the outcome of vessel remodelling. PMID:24720886

Zhu, Feng-Ping; Zhang, Yu; Higurashi, Masakazu; Xu, Bin; Gu, Yu-Xiang; Mao, Ying; Morgan, Michael Kerin; Qian, Yi

2014-06-01

15

After the super MCA  

International Nuclear Information System (INIS)

The German Federal Government in Bonn walked into the trap. Enthusiastic about the chance to blame the Soviet Union for bad reactor designs and even worse an information policy, our Government voluntarily drew a two-faced picture of inadequacy and danger (threatening the East) and of better standards and performance (shielding the Western world). To get out of the contradiction it created, the Government now starts a policy intended to calm down excitements, trying to cure the shock by sounding the all-clear signal. This book is aimed at disturbing this therapy. It presents the antedote: Information on - the presumed MCA scenario at Chernobyl, the Soviet nuclear energy programme, the chaotic information policy observed in the FRG, the hazards of prolonged radiation exposure, radioactivity, its nature and effects, reactions of people affected, the chances of local initiatives and necessary and feasible strategies of opting out of the nuclear power programme. Erhard Eppler, Klaus Traube, Lutz Mez, Rainer Griesshammer and many other authors came forward with a variety of papers presenting their assessment of the new situation, after the Chernobyl disaster. One common judgment of all the contributions is: The Chernobyl accident has not added any new arguments in disproof of the dangerousness of nuclear energy - all the well-known facts against the utilisation of nuclear power remaining unshattered -, but instead revealed so-called experts as professional minimizers, and their soothing strategies as an institutionalized lack of responsibility. (orig./HP)

16

Mini-MCA: an intelligent inspection instrument  

International Nuclear Information System (INIS)

The small portable multichannel analyzer (Mini-MCA) designed at Los Alamos National Laboratory is an intelligent safeguards instrument developed for the IAEA under the United States Aid Program. The Mini-MCA is a basic 1-k channel MCA that features a high degree of user friendliness and portability. Its history, use, and future applications are discussed. 5 figures, 3 tables

17

A data processor interface for 4-K MCA  

International Nuclear Information System (INIS)

A data processing system has been designed for use with the indigenous 4-K MCA. It consists of Micro 2200 - a programmable calculator, Micro data Interface (MDI), floppy disk attachment to Micro and a Data Interface specially designed for the transfer of data from MCA to Micro 2200 and for reverse transfer. This complete system enables one to transfer the spectrum from MCA, and to carry out desired spectrum analysis. The system has been used for routine analysis of energy dispersive XRF spectra. The report describes the hardware design of the Data Interface and the software of data transfer and standard spectrum analysis routines. Listing of Micro programmes for transfer and analysis are also given in the report. (author)

18

The super MCA of Chernobyl  

International Nuclear Information System (INIS)

Eleven correspondents and reporters of the weekly DIE ZEIT collected facts and data for this report of the world's worst nuclear accident. Thomas von Randow explains the main design features and the functions of the reactor that failed. Guenther Haaf outlines the hazardous effects on the population's health, and what can be done to provide protection. In an interview with Klaus Traube, the former nuclear industry manager who now belongs to the opponents of nuclear energy, says that the super MCA cannot be excluded, nowhere. Erhard Eppler and Heinz Riesenhuber present their views of the future of nuclear energy. (orig./GL)

19

Applications of a portable MCA in nuclear safeguards  

International Nuclear Information System (INIS)

In 1981 a small, battery-operated multichannel analyzer (MCA) prototype developed at Los Alamos National Laboratory was delivered to the International Atomic Energy Agency (IAEA). The intent was to produce an instrument for inspector (nonscientist) use. Automated measurement programs were built into the MCA. An enhanced, commercially produced MCA is now available, which was patterned after and is software compatible with the prototype. After an extensive review of the hardware and software of the available portable MCAs, the IAEA has chosen this MCA to be used by IAEA inspectors throughout the world. Inspectors from the EURATOM Directorate of Safeguards are also using these MCAs in inspections throughout Europe. While this MCA's portability and programmability make it ideally suited for infield applications, its powerful built-in intelligence and communications protocol make it a strong candidate for distributed data acquisition and control systems. The user-instrument interface philosophy is so easy to use that in domestic and international training schools, the operators manual is not used

20

Linear analysis near a steady-state of biochemical networks: control analysis, correlation metrics and circuit theory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background: Several approaches, including metabolic control analysis (MCA), flux balance analysis (FBA), correlation metric construction (CMC), and biochemical circuit theory (BCT), have been developed for the quantitative analysis of complex biochemical networks. Here, we present a comprehensive theory of linear analysis for nonequilibrium steady-state (NESS) biochemical reaction networks that unites these disparate approaches in a common mathematical framework and ...

Qian Hong; Beard Daniel A; Heuett William J

2008-01-01

 
 
 
 
21

Metabolic control analysis of respiration in human cancer tissue.  

Science.gov (United States)

Bioenergetic profiling of cancer cells is of great potential because it can bring forward new and effective therapeutic strategies along with early diagnosis. Metabolic Control Analysis (MCA) is a methodology that enables quantification of the flux control exerted by different enzymatic steps in a metabolic network thus assessing their contribution to the system's function. Our main goal is to demonstrate the applicability of MCA for in situ studies of energy metabolism in human breast and colorectal cancer cells as well as in normal tissues. We seek to determine the metabolic conditions leading to energy flux redirection in cancer cells. A main result obtained is that the adenine nucleotide translocator exhibits the highest control of respiration in human breast cancer thus becoming a prospective therapeutic target. Additionally, we present evidence suggesting the existence of mitochondrial respiratory supercomplexes that may represent a way by which cancer cells avoid apoptosis. The data obtained show that MCA applied in situ can be insightful in cancer cell energetic research. PMID:23825460

Kaambre, Tuuli; Chekulayev, Vladimir; Shevchuk, Igor; Tepp, Kersti; Timohhina, Natalja; Varikmaa, Minna; Bagur, Rafaela; Klepinin, Aleksandr; Anmann, Tiia; Koit, Andre; Kaldma, Andrus; Guzun, Rita; Valvere, Vahur; Saks, Valdur

2013-01-01

22

The SO-20.3 MC&A modernization plan final report.  

Energy Technology Data Exchange (ETDEWEB)

Materials Control and Accountability (MC&A) provides assurance to the nation that nuclear materials are controlled in accordance with their strategic and economic importance and that the misuse, theft or diversion of these materials will be detected. MC&A plays an important part in security at nuclear facilities, especially in addressing threats such as theft of materials, environmental contamination, and nuclear safety incidents associated with nuclear materials. For this reason, it is important that MC&A takes advantage of new technologies and methods in order to provide information on a site's nuclear materials in the most timely and useful manner possible. Within the U.S. Department of Energy (DOE), the Office of Security Policy, Policy Integration and Technical Support Program (SO-20.3) is responsible for the development of safeguards and security technology that enables DOE and NNSA facilities to safeguard their Special Nuclear Materials. The SO-20.3 Program tasked safeguards personnel at Los Alamos National Laboratory to lead a project with representatives from the Y-12 Plant, Lawrence Livermore National Laboratory, and the Savannah River Site to prepare an MC&A Modernization Plan that provides recommendations for development new technologies and methodologies for MC&A in both new and existing DOE facilities. The team was tasked with taking into account new concerns about the protection of nuclear material following the attacks of September 11, 2001. Opportunities for applying new MC&A approaches and technologies that provide increased freedom of operation, increased security and provide a potential for cost savings in existing and new DOE facilities are discussed in this report.

Longmire, V. L. (Victoria L.); Ensslin, Norbert; Files, C. (Chistina); Joseph, Joshua A., Jr.; Rudy, C. R. (Clifford R.); Smith, M. K. (Morag K.); Russo, P. A. (Phyllis A.); Stevens, R. S. (Rebecca S.); Strittmatter, R. B. (Richard B.); Wilkey, D. D. (David Dennis); Pickett, C. (Chris); Brosey, W. (William); Swanson, J. (Joel)

2004-01-01

23

Metabolic control analysis of xylose catabolism in Aspergillus  

DEFF Research Database (Denmark)

A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out, and flux control was shown to be dependent on the metabolite levels. Due to thermodynamic constraints, flux control may reside at the first step in the pathway, i.e., at the xylose reductase, even when the intracellular xylitol concentration is high. On the basis of the kinetic analysis, the general dogma specifying that flux control often resides at the step following an intermediate present at high concentrations was, therefore, shown not to hold. The intracellular xylitol concentration was measured in batch cultivations of two different strains of Aspergillus niger and two different strains of Aspergillus nidulans grown on media containing xylose, and a concentration up to 30 mM was found. Applying MCA showed thatthe first polyol dehydrogenase (XDH) in the catabolic pathway of xylose exerted the main flux control in the two strains of A. nidulans and A. niger NW324, but the flux control was exerted mainly at the first enzyme of the pathway (XR) of A. niger NW 296.

Prathumpai, Wai; Mcintyre, Mhairi

2003-01-01

24

Linear analysis near a steady-state of biochemical networks: control analysis, correlation metrics and circuit theory  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background: Several approaches, including metabolic control analysis (MCA, flux balance analysis (FBA, correlation metric construction (CMC, and biochemical circuit theory (BCT, have been developed for the quantitative analysis of complex biochemical networks. Here, we present a comprehensive theory of linear analysis for nonequilibrium steady-state (NESS biochemical reaction networks that unites these disparate approaches in a common mathematical framework and thermodynamic basis. Results: In this theory a number of relationships between key matrices are introduced: the matrix A obtained in the standard, linear-dynamic-stability analysis of the steady-state can be decomposed as A = SRT where R and S are directly related to the elasticity-coefficient matrix for the fluxes and chemical potentials in MCA, respectively; the control-coefficients for the fluxes and chemical potentials can be written in terms of RT BS and ST BS respectively where matrix B is the inverse of A; the matrix S is precisely the stoichiometric matrix in FBA; and the matrix eAt plays a central role in CMC. Conclusion: One key finding that emerges from this analysis is that the well-known summation theorems in MCA take different forms depending on whether metabolic steady-state is maintained by flux injection or concentration clamping. We demonstrate that if rate-limiting steps exist in a biochemical pathway, they are the steps with smallest biochemical conductances and largest flux control-coefficients. We hypothesize that biochemical networks for cellular signaling have a different strategy for minimizing energy waste and being efficient than do biochemical networks for biosynthesis. We also discuss the intimate relationship between MCA and biochemical systems analysis (BSA.

Qian Hong

2008-05-01

25

A Practical MC&A Inspection Training Approach for Gosatomnadzor of Russia  

Energy Technology Data Exchange (ETDEWEB)

The Russian nuclear materials control and accounting (MC&A) program has undergone many changes over the last five years. New technologies have been introduced; personnel have been trained; and new regulations are being developed. Gosatomnadzor of Russia (GAN), as the state oversight authority for the control and accounting of nuclear materials used for civil purposes, has the responsibility to assure that nuclear materials are controlled, accounted for, and used only for peaceful and defensive purposes. To ensure that GAN inspectors are fully capable and able to carry out this objective, an extensive training program has been developed. One activity under this program was a practical MC&A training exercise conducted in the U.S. at an Argonne National Laboratory-West (ANL-W) Category I nuclear material facility. This paper describes the development of the exercise in the U.S., the inspection activities conducted, an evaluation of the results, lessons learned, and recommendations for future inspector training programs.

Byers, Kenneth R.; Krupchatnikov, B.; Wright, T.; Key, C.; Coady, K.; Kilmartin, W.; Hawkins, R.; Kodman, G.

2000-08-01

26

Status of Activities to Implement a Sustainable System of MC&A Equipment and Methodological Support at Rosatom Facilities  

Energy Technology Data Exchange (ETDEWEB)

Under the U.S.-Russian Material Protection, Control and Accounting (MPC&A) Program, the Material Control and Accounting Measurements (MCAM) Project has supported a joint U.S.-Russian effort to coordinate improvements of the Russian MC&A measurement system. These efforts have resulted in the development of a MC&A Equipment and Methodological Support (MEMS) Strategic Plan (SP), developed by the Russian MEM Working Group. The MEMS SP covers implementation of MC&A measurement equipment, as well as the development, attestation and implementation of measurement methodologies and reference materials at the facility and industry levels. This paper provides an overview of the activities conducted under the MEMS SP, as well as a status on current efforts to develop reference materials, implement destructive and nondestructive assay measurement methodologies, and implement sample exchange, scrap and holdup measurement programs across Russian nuclear facilities.

J.D. Sanders

2010-07-01

27

Multi criteria analysis in environmental management: Selecting the best stormwater erosion and sediment control measure in Malaysian construction sites  

Energy Technology Data Exchange (ETDEWEB)

Malaysia located in a tropical region which is interested with a heavy rainfall through the whole seasons of the year. Construction stages usually associated with soil disturbing due to land clearing and grading activities, this combined with the tropical climate in Malaysia, will generate an enormous amount of soil to be eroded and then deposited in the adjacent water bodies. There are many kinds of mitigation measures used so as to reduce the impact of erosion and sedimentation that are generated due to the stormwater in construction sites. This paper presents the application of Multi Criteria Analysis (MCA) tool in choosing the best stormwater control measure by depending on specified criteria and criterion weight. The results obtained from the application of MCA in stormwater pollution control have many benefits to the contractors, consultants and decision makers by making them able to select the best control measure for every stage of construction.

Al-Hadu, Ibrahiem Abdul Razak; Sidek, Lariyah Mohd; Desa, Mohamed Nor Mohamed [Civil Engineering, Universiti Tenga Nasional, Kajang, Selangor (Malaysia); Basri, Noor Ezlin Ahmad [Civil and Structural Engineering, Universiti Kebangsaan Malyasia, Bangi, Selangor (Malaysia)

2011-07-01

28

The research of methods of multi-criteria analysis for increase of reliability of distribution networks by remote-controlled elements  

Energy Technology Data Exchange (ETDEWEB)

Multi-criteria analysis (MCA) was used to evaluate the remote control components of an electrical network. The study included assessments of the weighted sum approach; ideal points analysis; the technique for order preference by similarity to ideal solution (TOPSIS); and, concordance-discordance analysis. A standardized matrix was created for the evaluation. A weight was assigned to each criterion in order to assess the importance of particular criteria in relation to other criteria. The Fuller triangle method was then used to determine the number of preferences over other criteria. The Saaty method was used to calculate the eigen vector. Results of the study showed that the application of remote control components shortened the duration of faults in the network by accelerating handling times. Methods of paired comparison provided optimal solutions for the problems presented during the analysis. It was concluded that the MCA method successfully located areas in the network that were suitable for remote control components. 5 refs., 4 figs.

Hradilek, Z.; Krejci, P. [Technical Univ. of Ostrava, Ostrava (Czech Republic)

2005-07-01

29

MC&A software assistance to Ukraine  

Energy Technology Data Exchange (ETDEWEB)

AIMAS (Automated Inventory/Material Accounting System) is a PC-based application that is being developed as part of the U.S. assistance program to Ukraine in Nuclear Material Protection, Control, and Accounting (MPC&A). The AIMAS software prototype was designed to provide a starting point for joint U.S./Ukraine system development. Computer systems with AIMAS prototypes have been installed at Kiev Institute of Nuclear Research (KINR), Sevastopol Institute of Nuclear Energy & Industry (SINEI) and the Ministry of Environmental Protection and Nuclear Safety database management system (RDBMS) and application development environment. It has been designed to be highly flexible and configurable, and to support a wide range of computing infrastructure needs and facility requirements. AIMAS functions include basic physical inventory tracking, transaction histories, reporting, and system administration functions (system configuration and security). Security measures include multilevel password access controls, all transactions logged with the user ID, and system administration controls. Interfaces to external modules are being designed to provide nuclear fuel burn-up adjustment and barcode scanning capabilities for physical inventory taking. 1 ref.

Ewing, T.; McWilliams, C.; Olson, A. [and others

1997-09-01

30

MCA Based Performance Evaluation of Project Selection  

CERN Document Server

Multi-criteria decision support systems are used in various fields of human activities. In every alternative multi-criteria decision making problem can be represented by a set of properties or constraints. The properties can be qualitative & quantitative. For measurement of these properties, there are different unit, as well as there are different optimization techniques. Depending upon the desired goal, the normalization aims for obtaining reference scales of values of these properties. This paper deals with a new additive ratio assessment method. In order to make the appropriate decision and to make a proper comparison among the available alternatives Analytic Hierarchy Process (AHP) and ARAS have been used. The uses of AHP is for analysis the structure of the project selection problem and to assign the weights of the properties and the ARAS method is used to obtain the final ranking and select the best one among the projects. To illustrate the above mention methods survey data on the expansion of optic...

Bakshi, Tuli

2011-01-01

31

Effect of STA-MCA bypass based on the motor activation SPECT  

International Nuclear Information System (INIS)

The effect of STA-MCA bypass for ischemic cerebrovascular diseases (CVDs) on pure motor function using motor activation SPECT was evaluated and analyzed, and this effect with the resting cerebral blood flow and reserved capacity was compared. Motor activation SPECT were carried out on 22 cases with STA-MCA bypass for symptomatic ischemic CVDs. All motors activation SPECT using the finger opposition task on the affected side were performed before bypass, at 1 month, and 3 months after the bypass. Visual inspection was used to determine whether the result of the motor activation SPECT was as negative or positive. The activated region was detected anatomically precisely by superimposing the SPECT on the MRI. Before this study, the same examination was performed on normal controls. In controls, 91% showed the activated area on the sensorimotor cortex after the finger opposition tasks. Before bypass, the resting SPECT revealed reduction of cerebral blood flow (CBF) on the affected side in all cases. All cases also showed a disturbed response to acetazolamide (ACZ). Nine cases were positive in the motor activation SPECT. One month after bypass, the resting CBF increased in 11 cases. Seven showed preoperative positive motor activation. Fifteen cases were positive in the motor activation SPECT. Three months after bypass, 20 cases showed improvement in the resting CBF, and 19 cases were positive in the motor activation SPECT. Ten cases were negative in the preoperative motor activation SPECT. At one month after surgery, ACZ activation SPECT was performed in 12 cases. Five showed improvement of the response to ACZ. At 3 months after surgery, 8 of 12 cases treated with ACZ activation SPECT showed improved response to ACZ. In most of the cases, improved response to ACZ could be seen after response to motor activation improved. STA-MCA bypass is useful not only for resting CBF but also for pure motor function based on motor activation SPECT. (K.H.)

32

Effect of STA-MCA bypass based on the motor activation SPECT  

Energy Technology Data Exchange (ETDEWEB)

The effect of STA-MCA bypass for ischemic cerebrovascular diseases (CVDs) on pure motor function using motor activation SPECT was evaluated and analyzed, and this effect with the resting cerebral blood flow and reserved capacity was compared. Motor activation SPECT were carried out on 22 cases with STA-MCA bypass for symptomatic ischemic CVDs. All motors activation SPECT using the finger opposition task on the affected side were performed before bypass, at 1 month, and 3 months after the bypass. Visual inspection was used to determine whether the result of the motor activation SPECT was as negative or positive. The activated region was detected anatomically precisely by superimposing the SPECT on the MRI. Before this study, the same examination was performed on normal controls. In controls, 91% showed the activated area on the sensorimotor cortex after the finger opposition tasks. Before bypass, the resting SPECT revealed reduction of cerebral blood flow (CBF) on the affected side in all cases. All cases also showed a disturbed response to acetazolamide (ACZ). Nine cases were positive in the motor activation SPECT. One month after bypass, the resting CBF increased in 11 cases. Seven showed preoperative positive motor activation. Fifteen cases were positive in the motor activation SPECT. Three months after bypass, 20 cases showed improvement in the resting CBF, and 19 cases were positive in the motor activation SPECT. Ten cases were negative in the preoperative motor activation SPECT. At one month after surgery, ACZ activation SPECT was performed in 12 cases. Five showed improvement of the response to ACZ. At 3 months after surgery, 8 of 12 cases treated with ACZ activation SPECT showed improved response to ACZ. In most of the cases, improved response to ACZ could be seen after response to motor activation improved. STA-MCA bypass is useful not only for resting CBF but also for pure motor function based on motor activation SPECT. (K.H.)

Kawaguchi, Shoichiro; Uranishi, Ryunosuke; Sakaki, Toshisuke; Imai, Teruhiko; Ohishi, Hajime [Nara Medical Univ., Kashihara (Japan)

1999-07-01

33

MATERIAL CONTROL ACCOUNTING INMM  

Energy Technology Data Exchange (ETDEWEB)

Since 1996, the Mining and Chemical Combine (MCC - formerly known as K-26), and the United States Department of Energy (DOE) have been cooperating under the cooperative Nuclear Material Protection, Control and Accounting (MPC&A) Program between the Russian Federation and the U.S. Governments. Since MCC continues to operate a reactor for steam and electricity production for the site and city of Zheleznogorsk which results in production of the weapons grade plutonium, one of the goals of the MPC&A program is to support implementation of an expanded comprehensive nuclear material control and accounting (MC&A) program. To date MCC has completed upgrades identified in the initial gap analysis and documented in the site MC&A Plan and is implementing additional upgrades identified during an update to the gap analysis. The scope of these upgrades includes implementation of MCC organization structure relating to MC&A, establishing material balance area structure for special nuclear materials (SNM) storage and bulk processing areas, and material control functions including SNM portal monitors at target locations. Material accounting function upgrades include enhancements in the conduct of physical inventories, limit of error inventory difference procedure enhancements, implementation of basic computerized accounting system for four SNM storage areas, implementation of measurement equipment for improved accountability reporting, and both new and revised site-level MC&A procedures. This paper will discuss the implementation of MC&A upgrades at MCC based on the requirements established in the comprehensive MC&A plan developed by the Mining and Chemical Combine as part of the MPC&A Program.

Hasty, T.

2009-06-14

34

Automation of a pneumatic system by controlling a microcomputer equipped with a custom add on board for neutron activation analysis  

International Nuclear Information System (INIS)

An automated sample transfer system associated with a 3 x 592 GBq Am-Be neutron source has been constructed at the Ankara Nuclear Research and Training Center (ANRTC) for Instrumental Neutron Activation Analysis (INAA) and Cyclic Instrumental Neutron Activation Analysis (CINAA). The pneumatic transfer system is controlled by an IBM PS/1 personal computer which is equipped with a custom add-on board for relevant hardware and control software written in Turbo Pascal. The system computer interactively works with a Multichannel Analyzer (MCA) for proper data acquisition. The sample transfer system also runs manually. The design and performance of the hardware and software are discussed. (Author)

35

Collapse of the western North America climate dipole during the MCA and LIA  

Science.gov (United States)

Understanding of the teleconnections between regional climate regimes and the time-scale of the stability of these teleconnections is crucial for building predictive models of climate change. Using annually-resolved speleothem physical (band thickness, hiatus and mineralogy) and oxygen and carbon isotopic effective moisture proxy data, we show climate variability in the southwestern United States (SW) during the critical Medieval Climate Anomaly and Little Ice Age (LIA) intervals. Although the MCA overall was not markedly drier than the wet latter half of the LIA, it was punctuated by multiple megadroughts. The driest interval was the early LIA, during which we identify an extended multi-century drought, which we will refer to as a Super Drought (SD), occurring during the early LIA ca. AD 1350 to AD 1650. There is a well-established dipole response to Pacific Decadal Oscillation (PDO) and El Nino-Southern Oscillation (ENSO) variability between the SW and northwestern United States (NW), and the SW and the Asian monsoon during the modern and overall Holocene climate regime. Our data indicate that this climate dipole apparently collapsed during the MCA-LIA, extending back to about 300 AD, such that pluvial and drought intervals in the SW and NW, and SW and Asian monsoon occur contemporaneously over this period. The modern positive relationship between moisture and the PDO observed in the SW is also reversed. During this interval the PDO is negatively correlated with SW moisture amount. In addition, the strong solar control of Holocene climate observed previously in western North America and the Asian monsoon is weakened during parts of this interval, such that solar maxima and minima do not correlate coherently with precipitation variability both in North America and the Asian monsoon. The MCA-early LIA period in which the megadroughts dominate occurs within the prominently positive phase of the North Atlantic Oscillation (NAO). One potential mechanism of propagating change in the PDO-driven winter and AMO-driven North American monsoon summer precipitation variability would be through changes in the strength of Arctic Oscillation (AO). The AO can potentially modulate winter and summer precipitation simultaneously to the extent that the AO variability seems to lead changes in the PDO and the AO expresses itself as the NAO in the North Atlantic.

Asmerom, Y.; Polyak, V. J.; Rasmussen, J.; Burns, S. J.; Lachniet, M. S.

2011-12-01

36

Comparison of magnetic resonance angiography to digital subtraction angiography for diagnosis of MCA stenosis  

International Nuclear Information System (INIS)

Objective: To evaluate the diagnostic value of MRA in detecting MCA stenosis or occlusion compared with DSA. Methods: 35 patients with ischemic cerebrovascular disease underwent both MRA and DSA. Based on the results of DSA, the gold standard, we analyzed the diagnostic value of MRA for detecting MCA stenosis of different degrees. Results: 70 middle cerebral arteries (MCA) are examined in 35 patients. Based on the results of MRA, 28 arteries are normal, 42 arteries are stenostic or occlusive, and 47 segments are stenostic or occlusive. 53 segments are diagnosed consistently by MRA and DSA. The rate of coincidence is 70.67%. The degree of stenosis in MRA is higher than in DSA in 22 segments. In mild degree stenosis, the sensitivity, specificity, accuracy, positive predictive value, negative predictive value of MRA are 100%, positive Likelihood Ratio is ?, and negative predictive value is 0. In moderate degree, they are 100%, 71.4%, 73.1%, 17.6%, 100%, 3.5, 0; In severe degree, they are 100%, 81.4%, 82%, 15.4%, 100%, 5.38, 0; In occlusive MCA, they are 100%, 96.8%, 977.3%, 86.7%, 100%, 31.25, 0. For diagnosis of MRA in mild, moderate, severe degree of stenotic or occlusive MCA, Kappa values are 1.0, 0.224, 0.222, 0.912. Conclusion: Compared with DSA, the diagnostic values of MRA for detecting MCA stenosis are different according to different degrees of stenosis. The sensitivity and specificity are highest in MRA diagnosis of mild degree MCA stenosis. So MRA is a suitable option for MCA stenosis screening. The diagnostic values of MRA are lower in moderate, and severe degree MCA stenosis. The means of DSA is more helpful. Though there is a high accordance rate in occlusive MCA, the results of MRA should be also treated carefully. (authors)

37

Mechanosensitive channel candidate MCA2 is involved in touch-induced root responses in Arabidopsis.  

Science.gov (United States)

The Ca(2+)-permeable mechanosensitive (MS) channel is a mechanical stress sensor. We previously reported that Arabidopsis MCA1 and its paralog MCA2 functioned individually as Ca(2+)-permeable MS channels. In the present study, we showed that the primary roots of the mca2-null mutant behaved abnormally on the surface of hard medium. First, primary roots are known to exhibit a skewing growth pattern on the surface of vertically placed agar medium. On such surface, the primary roots of mca2-null skewed more than those of the wild type. Second, when seedlings were grown on a tilted agar surface, the primary root of mca2-null showed abnormal waving patterns. Third, wild-type seedlings eventually died when grown on horizontally placed 3.2% gelrite medium, which was too hard to allow the primary roots of the wild type to penetrate, because their primary roots sprang from the surface of the medium and may have been unable to absorb water and nutrients. In contrast, the primary roots of mca2-null, but not those of mca1-null, were able to creep over the surface of the medium and grow. Fourth, when grown on the surface of 3.2% agar medium supplemented with 30 mM CaCl2, only mca2-null grew with a root that coiled in a clockwise direction. Lastly, on the surface of vertically placed rectangular plates that allowed primary roots to grow vertically down to the frame of the plate, wild-type primary roots grew horizontally after touching the frame at an angle of 90(?). During the horizontal growth, only the extreme root tips maintained contact with the frame. In contrast, the primary roots of mca2-null allowed not only the extreme root tips, but also the meristem and elongation zones to maintain contact with the frame during horizontal growth. These results suggest that MCA2 is involved in touch-related root responses. PMID:25191336

Nakano, Masataka; Samejima, Rika; Iida, Hidetoshi

2014-01-01

38

Mechanosensitive channel candidate MCA2 is involved in touch-induced root responses in Arabidopsis  

Science.gov (United States)

The Ca2+-permeable mechanosensitive (MS) channel is a mechanical stress sensor. We previously reported that Arabidopsis MCA1 and its paralog MCA2 functioned individually as Ca2+-permeable MS channels. In the present study, we showed that the primary roots of the mca2-null mutant behaved abnormally on the surface of hard medium. First, primary roots are known to exhibit a skewing growth pattern on the surface of vertically placed agar medium. On such surface, the primary roots of mca2-null skewed more than those of the wild type. Second, when seedlings were grown on a tilted agar surface, the primary root of mca2-null showed abnormal waving patterns. Third, wild-type seedlings eventually died when grown on horizontally placed 3.2% gelrite medium, which was too hard to allow the primary roots of the wild type to penetrate, because their primary roots sprang from the surface of the medium and may have been unable to absorb water and nutrients. In contrast, the primary roots of mca2-null, but not those of mca1-null, were able to creep over the surface of the medium and grow. Fourth, when grown on the surface of 3.2% agar medium supplemented with 30 mM CaCl2, only mca2-null grew with a root that coiled in a clockwise direction. Lastly, on the surface of vertically placed rectangular plates that allowed primary roots to grow vertically down to the frame of the plate, wild-type primary roots grew horizontally after touching the frame at an angle of 90?. During the horizontal growth, only the extreme root tips maintained contact with the frame. In contrast, the primary roots of mca2-null allowed not only the extreme root tips, but also the meristem and elongation zones to maintain contact with the frame during horizontal growth. These results suggest that MCA2 is involved in touch-related root responses.

Nakano, Masataka; Samejima, Rika; Iida, Hidetoshi

2014-01-01

39

A reliable approach to distinguish between transient with and without HFOs using TQWT and MCA.  

Science.gov (United States)

Recent studies have reported that discrete high frequency oscillations (HFOs) in the range of 80-500Hz may serve as promising biomarkers of the seizure focus in humans. Visual scoring of HFOs is tiring, time consuming, highly subjective and requires a great deal of mental concentration. Due to the recent explosion of HFOs research, development of a robust automated detector is expected to play a vital role in studying HFOs and their relationship to epileptogenesis. Therefore, a handful of automated detectors have been introduced in the literature over the past few years. In fact, all the proposed methods have been associated with high false-positive rates, which essentially arising from filtered sharp transients like spikes, sharp waves and artifacts. In order to specifically minimize false positive rates and improve the specificity of HFOs detection, we proposed a new approach, which is a combination of tunable Q-factor wavelet transform (TQWT), morphological component analysis (MCA) and complex Morlet wavelet (CMW). The main findings of this study can be summarized as follows: The proposed method results in a sensitivity of 96.77%, a specificity of 85.00% and a false discovery rate (FDR) of 07.41%. Compared to this, the classical CMW method applied directly on the signals without pre-processing by TQWT-MCA achieves a sensitivity of 98.71%, a specificity of 18.75%, and an FDR of 29.95%. The proposed method may be considered highly accurate to distinguish between transients with and without HFOs. Consequently, it is remarkably reliable and robust for the detection of HFOs. PMID:24814526

Chaibi, Sahbi; Lajnef, Tarek; Sakka, Zied; Samet, Mounir; Kachouri, Abdennaceur

2014-07-30

40

Effect of transformation induced in vitro by combined treatment with Co-60 gamma rays and 3-MCA on human embryo lung cells  

International Nuclear Information System (INIS)

Numerous carcinogens in the environment such as radiation, chemicals and viruses may act on human body simultaneously and cause carcinogenesis. It is, therefore, important to study the possible synergistic effects of these carcinogens on carcinogenesis. In this report some preliminary results are given of biological and morphological characteristics of transformation induced in vitro by combined treatment with Co-60 gamma rays and 3-methylcho-eanthrene (3-MCA) on diploid human embryo lung cell line (HEL-8315, passages 7). The results indicated that the transformation rate of human embryo long cells increased considerably when treated with both gamma rays (1.0 Gy) and 3-MCA (1.0 ?g/ml). The transformed cells in the combined treatment group were different from those in the control group, dimethylsulfoxide (DMSO, less than 0.01% in the culture media)-treated group and those treated with 3-MCA or gamma rays alone respectively: (a) The chromosome aberration rate of the combined treatment group is higher than that of other groups. Aberration of chromatid type was also observed in the group. (b) The ability to form colonies in semi-soft agar media was enhanced in the combined treatment group and higher than that in other groups. (c) Ring foci were formed only in the combined treatment group. The results suggest that the transformation rate of the combined treatment group is higher than that of the group treated by either gamma rays or 3-MCAr 3-MCA

 
 
 
 
41

Inspector-2000. A DSP-based, portable, multi-purpose MCA  

International Nuclear Information System (INIS)

Various in-situ gamma-spectroscopy applications need a versatile, multi-purpose, portable multi-channel analyzer (MCA). Recently, Canberra has introduced the Inspector-2000 for this purpose. It uses digital signal processing (DSP) technology and weighs only about 1.2 kg. It also supports CdTe, NaI and Ge detectors. Due to its use of DSP technology, the Inspector-2000 also provides a longer battery life, a better detector resolution and a better temperature stability than most portable MCAs. A short description of the Inspector-2000 MCA is included and its performance characteristics compared to an analog MCA. (author)

42

Implementation of MCA Method for Identification of Factors for Conceptual Cost Estimation of Residential Buildings  

Science.gov (United States)

Conceptual cost estimation is important for construction projects. Either underestimation or overestimation of building raising cost may lead to failure of a project. In the paper authors present application of a multicriteria comparative analysis (MCA) in order to select factors influencing residential building raising cost. The aim of the analysis is to indicate key factors useful in conceptual cost estimation in the early design stage. Key factors are being investigated on basis of the elementary information about the function, form and structure of the building, and primary assumptions of technological and organizational solutions applied in construction process. The mentioned factors are considered as variables of the model which aim is to make possible conceptual cost estimation fast and with satisfying accuracy. The whole analysis included three steps: preliminary research, choice of a set of potential variables and reduction of this set to select the final set of variables. Multicriteria comparative analysis is applied in problem solution. Performed analysis allowed to select group of factors, defined well enough at the conceptual stage of the design process, to be used as a describing variables of the model.

Juszczyk, Micha?; Le?niak, Agnieszka; Zima, Krzysztof

2013-06-01

43

Applications of a portable MCA in nuclear safeguards  

International Nuclear Information System (INIS)

The DSD-2056-4K portable multi-channel analyzer (PMCA) is a standard tool used in both international and domestic safeguards. This tool and the built-in user programs have been field proven. For applications where the manpower to program built-in programs is not available, programs in external computers can control the PMCA. A set of general purpose setup and analysis subroutines have been written in BASIC to be used directly or as a guide in the external applications. While safeguards and the nuclear industry are just beginning to make use of the present PMCA, we are looking into ways of making it easier to write internal programs for the PMCA and into replacing its current 8-bit processor with a 16-bit processor to give it the capability to do very involved analysis such as peak fitting and detailed plutonium isotopic analysis. 8 refs., 3 figs

44

Applications of a portable MCA in nuclear safeguards  

Energy Technology Data Exchange (ETDEWEB)

The DSD-2056-4K portable multi-channel analyzer (PMCA) is a standard tool used in both international and domestic safeguards. This tool and the built-in user programs have been field proven. For applications where the manpower to program built-in programs is not available, programs in external computers can control the PMCA. A set of general purpose setup and analysis subroutines have been written in BASIC to be used directly or as a guide in the external applications. While safeguards and the nuclear industry are just beginning to make use of the present PMCA, we are looking into ways of making it easier to write internal programs for the PMCA and into replacing its current 8-bit processor with a 16-bit processor to give it the capability to do very involved analysis such as peak fitting and detailed plutonium isotopic analysis. 8 refs., 3 figs.

Halbig, J.K.; Klosterbuer, S.F.; Cameron, R.A.

1985-01-01

45

Metabolic control analysis of cellular respiration in situ in intraoperational samples of human breast cancer.  

Science.gov (United States)

The aim of this study was to analyze quantitatively cellular respiration in intraoperational tissue samples taken from human breast cancer (BC) patients. We used oxygraphy and the permeabilized cell techniques in combination with Metabolic Control Analysis (MCA) to measure a corresponding flux control coefficient (FCC). The activity of all components of ATP synthasome, and respiratory chain complexes was found to be significantly increased in human BC cells in situ as compared to the adjacent control tissue. FCC(s) were determined upon direct activation of respiration with exogenously-added ADP and by titrating the complexes with their specific inhibitors to stepwise decrease their activity. MCA showed very high sensitivity of all complexes and carriers studied in human BC cells to inhibition as compared to mitochondria in normal oxidative tissues. The sum of FCC(s) for all ATP synthasome and respiratory chain components was found to be around 4, and the value exceeded significantly that for normal tissue (close to 1). In BC cells, the key sites of the regulation of respiration are Complex IV (FCC?=?0.74), ATP synthase (FCC?=?0.61), and phosphate carrier (FCC?=?0.60); these FCC(s) exceed considerably (~10-fold) those for normal oxidative tissues. In human BC cells, the outer mitochondrial membrane is characterized by an increased permeability towards adenine nucleotides, the mean value of the apparent K(m) for ADP being equal to 114.8?±?13.6 ?M. Our data support the two-compartment hypothesis of tumor metabolism, the high sum of FCC(s) showing structural and functional organization of mitochondrial respiratory chain and ATP synthasome as supercomplexes in human BC. PMID:22836527

Kaambre, Tuuli; Chekulayev, Vladimir; Shevchuk, Igor; Karu-Varikmaa, Minna; Timohhina, Natalja; Tepp, Kersti; Bogovskaja, Jelena; Kütner, Riina; Valvere, Vahur; Saks, Valdur

2012-10-01

46

MCA Center of Excellence Through Benchmarking and INMM Involvement - Key Tools for Change  

Energy Technology Data Exchange (ETDEWEB)

Nuclear Materials Management Department, a BWXT-corporate partner with Westinghouse Savannah River Company, has established a vision for positioning the organization as a Global Center of Excellence for Strategic Materials Management. NMM's Road to Excellence results from a changing business environment where flexibility and adaptability have become key demands from the Department of Energy customer. Flexibility and adaptability are integral components of the department's MC&A Center of Excellence philosophy in the pursuit of improvement technologies that meet domestic and international safeguards requirements. The customer challenge has put the organization in the forefront of change where benchmarking with other MC&A programs, applying human performance technologies and leveraging INMM leadership and participation opportunities are key ingredients to influencing improvements and changes in existing MC&A standards, policies and practices. The paper challenges MC&A professionals, MC&A program owners and organizational leaders to engage in the debate of new ideas, partnering arrangements and timely deployment of technologies (human performance and technical-based applications) to exponentially improve safeguards programs. Research and development efforts in support of safeguards improvements need to seriously consider deployment to field practitioners within a 2-3 year time frame from inception. INMM plays a crucial role in accelerating such opportunities and establishing improved performance standards above our normal governmental and organizational bureaucracies.

JAY, JEFFERY

2005-10-07

47

Construction of a reasonable multi channel analyzer (MCA) with an educational FPGA board  

International Nuclear Information System (INIS)

In resent years, the performances of new electronic devices, for example FPGA or so on, have been improved, and these devices become more cost-effective ones year by year. Moreover, prices of personal computers have become less expensive, and the programming environment on PC becomes much user-friendly and easy to operate in this decimal year. These advancements have possibilities to provide a great help for self-constructions of radiation measurement equipments, which needed huge cost and work to construct in the past. Then, I tried to construct a reasonable Mulch Channel Analyzer (MCA) with an educational FPGA board named EDX-005 (HuMANDATA ltd.), and conduct test measurements of the MCA. The MCA was constructed in a short period, and its cost was just under 50 thousands yen. The MCA normally works at 200 [cps/ch] count rate with a NaI(Tl) scintillation counter. The description of the MCA and some points of self-constructions of radiation measurement equipments are provided in this paper. (author)

48

Linking least-cost energy system costs models with MCA: An assessment of the EU renewable energy targets and supporting policies  

Energy Technology Data Exchange (ETDEWEB)

There are several technoeconomic modeling approaches that provide quantitative results such as costs and the level of achievement of certain renewable energy (RE) policy targets. These approaches often do not consider other important factors for policy implementation (such as socio-political aspects and stakeholders' preferences). Recent multicriteria analysis (MCA) approaches attempt to integrate these multiple aspects in decision making process. In this respect, aim of this paper is to combine technoeconomic modeling and MCA approaches in a general analytical framework incorporating multiple aspects. Each method in an RE policy interaction problem can feed in the necessary policy information for the subsequent steps of an ex-ante and an ex-post assessment in a decision tree, starting from recognizing the need for implementing a new policy in parallel to the incumbent ones, assessing the actual policy costs and finally identifying the social acceptability of these RE policies.

Oikonomou, V., E-mail: vlasis@jiqweb.or [Joint Implementation Network, Laan Corpus den Hoorn, 300, Groningen (Netherlands); Flamos, A., E-mail: aflamos@unipi.g [Department of Industrial Management and Technology, University of Piraeus, 80 Karaoli and Dimitriou str., 18534 Piraeus (Greece); Gargiulo, M., E-mail: Maurizio.gargiulo@e4sma.co [Energy Engineering Economic Environment Systems Modelling and Analysis S.r.L (34SMA), Turin (Italy); Giannakidis, G., E-mail: ggian@cres.g [Energy Systems Analysis Laboratory, Centre for Renewable Energy Sources and Savings, 19th Km Marathonos Ave. 19009 Pikermi, Attiki (Greece); Kanudia, A., E-mail: amit@kanors.co [Kanors, Vasundhra Enclave, Delhi (India); Spijker, E. [Joint Implementation Network, Laan Corpus den Hoorn, 300, Groningen (Netherlands); Grafakos, S., E-mail: s.grafakos@ihs.n [Dutch Research Institute For Transitions (Drift) and Institute for Housing and Urban Development Studies (IHS), Erasmus University Rotterdam, BurgemeesterOudlaan 50, P.O. Box 1935, 3000 BX, Rotterdam (Netherlands)

2011-05-15

49

Linking least-cost energy system costs models with MCA: An assessment of the EU renewable energy targets and supporting policies  

International Nuclear Information System (INIS)

There are several technoeconomic modeling approaches that provide quantitative results such as costs and the level of achievement of certain renewable energy (RE) policy targets. These approaches often do not consider other important factors for policy implementation (such as socio-political aspects and stakeholders' preferences). Recent multicriteria analysis (MCA) approaches attempt to integrate these multiple aspects in decision making process. In this respect, aim of this paper is to combine technoeconomic modeling and MCA approaches in a general analytical framework incorporating multiple aspects. Each method in an RE policy interaction problem can feed in the necessary policy information for the subsequent steps of an ex-ante and an ex-post assessment in a decision tree, starting from recognizing the need for implementing a new policy in parallel to the incumbent ones, assessing the actual policy costs and finally identifying the social acceptability of these RE policies.

50

Demonstrating patency of STA-MCA anastomosis with /sup 99m/Tc albumin microspheres  

International Nuclear Information System (INIS)

A patient with occlusion of the left internal carotid artery underwent an anastomosis between branches of the left superficial temporal and middle cerebral arteries (STA-MCA). A left carotid angiogram 9 days later showed extreme, tapered narrowing of the involved STA branch, with no filling of the MCA from the bypass. A year later, symptoms had improved slightly, and a minimally invasive study was made with /sup 99m/Tc human albumin microspheres. This showed patency of the bypass, with intracranial perfusion in the MCA field, findings later confirmed by a repeat left carotid angiogram. It appears that /sup 99m/Tc HAM scintigraphy will be useful in assessing the effectiveness of this and other bypass operations

51

An approximate protocol analysis with performance optimization for WDM networks  

Science.gov (United States)

In this study, our main goal is to investigate the performance optimization conditions for WDM networks. We introduce a network architecture of passive star topology that uses a Multi-channel Control Architecture (MCA) to avoid both the data channels and the receiver collisions. Especially, we propose a synchronous access scheme that exploits the propagation delay parameter in order to assign the data channels to the stations for successful data packet transmission. Thus, we achieve effective bandwidth utilization. An approximate analysis based on Poisson statistics is developed in order to explore the performance measures optimization. Finally, extensive comparative study is given for various stations populations and number of MCA channels.

Baziana, P. A.

2014-08-01

52

Status report on the TSA Systems, Ltd., MCA465 gamma-ray confirmation instrument  

Energy Technology Data Exchange (ETDEWEB)

The TSA Systems, Ltd., MCA465 is hand-portable, low resolution, gamma-ray instrument for confirming special nuclear materials (SNM) and related applications. The instrument evolved from earlier TSA Systems hand-held instruments, and, since its inception in 1991, it has been undergoing cycles of evaluation and then repair or redesign to correct problems. Through the efforts of Los Alamos, Rocky Flats, and TSA Systems, the MCA465 now has achieved commendable progress toward achieving quality performance as a rapid confirmation tool for SNM.

Fehlau, P.E.; Rutherford, D.A.

1994-08-01

53

Status report on the TSA Systems, Ltd., MCA465 gamma-ray confirmation instrument  

International Nuclear Information System (INIS)

The TSA Systems, Ltd., MCA465 is hand-portable, low resolution, gamma-ray instrument for confirming special nuclear materials (SNM) and related applications. The instrument evolved from earlier TSA Systems hand-held instruments, and, since its inception in 1991, it has been undergoing cycles of evaluation and then repair or redesign to correct problems. Through the efforts of Los Alamos, Rocky Flats, and TSA Systems, the MCA465 now has achieved commendable progress toward achieving quality performance as a rapid confirmation tool for SNM

54

Correlação de três variáveis na descrição da permeabilidade nasal (HD, MCA, escala NOSE) de pacientes saudáveis / Correlation of three variables describing nasal patency (HD, MCA, NOSE score) in healthy subjects  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Rinoresistometria e rinometria acústica são dois métodos utilizados na avaliação da função respiratória nasal. Ambos utilizam variáveis diferentes para descrever a permeabilidade nasal: o diâmetro hidráulico, HD, na rinoresistometria; e as áreas mínimas da seção transversal, MCA1 (istmo nasal) e MCA [...] 2 (cabeça do corneto inferior e corpo cavernoso do septo nasal), na rinometria acústica. OBJETIVO: Analisar a relação entre HD e MCA em pacientes sem afecções nasais e identificar se tais variáveis objetivas apresentam correlação com a escala NOSE, uma ferramenta validada para avaliar a percepção subjetiva de permeabilidade nasal. MÉTODO: Coleta estruturada dos dados de 24 indivíduos saudáveis sem afecções nasais. RESULTADOS: Correlações estatisticamente significativas de fracas a moderadas foram identificadas entre HD e MCA2 antes do descongestionamento. Foi identificada correlação moderada entre HD, MCA2 e escala NOSE no lado mais estreito. CONCLUSÃO: Na avaliação de permeabilidade nasal, parece ser recomendável determinar HD, MCA1 e MCA2, bem como uma variável subjetiva como a escala NOSE, que não aparentam ser variáveis completamente redundantes. Estudos futuros devem avaliar a correlação destas variáveis em pacientes com afecções nasais. Abstract in english Rhinoresistometry and acoustic rhinometry are two established apparative methods to objectify the respiratory function of the nose. Both methods use different variables to describe nasal patency: "hydraulic diameter", HD, in rhinoresistometry, and "minimal cross-sectional area", MCA1 (nasal isthmus) [...] and MCA2 (head of the inferior turbinate and cavernous body of the nasal septum), in acoustic rhinometry. OBJECTIVE: This study analyzes the mutual correlation of HD and MCA as a pilot study in patients without nasal pathologies. Additionally, we investigated if these objective variables correlate with the NOSE score, a validated tool to measure subjective perception of nasal patency. METHOD: Planned data collection in a collective of 24 healthy subjects without nasal pathologies. RESULTS: Statistically significant, weak to moderate correlations were found between HD and MCA2 before decongestion. A moderate correlation was found between both HD and MCA2 and the NOSE score on the narrower side. CONCLUSION: In the assessment of nasal patency, it seems advisable to determine HD, MCA1 and MCA2, but also a subjective variable such as the NOSE score, which all seem to be not fully redundant variables. In further studies, the correlation of the variables should be assessed in patients with nasal pathologies.

Thomas, Braun; Maria, Rich; Matthias F., Kramer.

2013-06-01

55

Design and synthesis of peptide-MCA substrates for a novel assay of histone methyltransferases and their inhibitors.  

Science.gov (United States)

Histone methyltransferases (HMTs) play an important role in controlling gene expression through site-specific methylation of lysines in core and linker histones within chromatin. As the typical HMTs, G9a and Set7/9 have been intensively studied that G9a is specific to the methylation at H3K9 and H3K27 and represses transcription, while Set7/9 methylates at H3K4. In this report we prepared various peptide-MCAs (4-methylcoumaryl-7-amides) related to histone tail and protein-substrates such as p53 and estrogen receptor-?. The fluorogenic substrates are applied for the assay of HMTs and an inhibitor, for example. The most sensitive and specific MCA-substrates to G9a and Set7/9 are discovered. The peptide-MCAs corresponding to the methylation sequences are promising for screening of HMT inhibitors. PMID:24486204

Chi, Hongfang; Takemoto, Yasushi; Nsiama, Tienabe K; Kato, Tamaki; Nishino, Norikazu; Ito, Akihiro; Yoshida, Minoru

2014-02-15

56

An Auto sequence Code to Integrate a Neutron Unfolding Code with thePC-MCA Accuspec  

International Nuclear Information System (INIS)

In a neutron spectrometry using proton recoil method, the neutronunfolding code is needed to unfold the measured proton spectrum to become theneutron spectrum. The process of the unfolding neutron in the existingneutron spectrometry which was successfully installed last year was doneseparately. This manuscript reports that the auto sequence code to integratethe neutron unfolding code UNFSPEC.EXE with the software facility of thePC-MCA Accuspec has been made and run successfully so that the new neutronspectrometry become compact. The auto sequence code was written based on therules in application program facility of PC-MCA Accuspec and then it wascompiled using AC-EXE. Result of the test of the auto sequence code showedthat for binning width 20, 30, and 40 giving a little different spectrumshape. The binning width around 30 gives a better spectrum in mean of givingsmall error compared to the others. (author)

57

Data transfer among Apple-II microcomputer, S-80 MCA and PDP-11 computer system  

International Nuclear Information System (INIS)

The data communication method described in this paper is designed to facilitate the data transfer among S-80 MCA, MS-900 Moessbauer spectrometer based on Apple-II microcomputer and PDP-11 computer system. Some simple processing for spectral data is available in the microcomputer. The least square fitting for spectral data is performed in PDP-11 computer system while the microcomputer is used as a terminal

58

NuSTAR ground calibration: The Rainwater Memorial Calibration Facility (RaMCaF)  

DEFF Research Database (Denmark)

The Nuclear Spectroscopic Telescope Array (NuSTAR) is a NASA Small Explorer mission that will carry the first focusing hard X-ray (5-80 keV ) telescope to orbit. The ground calibration of the three flight optics was carried out at the Rainwater Memorial Calibration Facility (RaMCaF) built for this purpose. In this article we present the facility and its use for the ground calibration of the three optics.

Brejnholt, Nicolai; Christensen, Finn Erland

2011-01-01

59

Admission Insular Infarction >25% is the Strongest Predictor of Large Mismatch Loss in Proximal MCA Stroke  

Science.gov (United States)

Background and Purpose Previous univariate analyses have suggested that proximal middle cerebral artery (MCA) infarcts with insular involvement have greater severity, and are more likely to progress into surrounding penumbral “tissue-at-risk”. We hypothesized that a practical, simple scoring method to assess percent insular-ribbon infarction (“PIRI-score”) would improve prediction of penumbral-loss over other common imaging biomarkers. Methods Of consecutive acute stroke patients from 2003–2008, forty-five with proximal-MCA-only occlusion met inclusion criteria, including available penumbral imaging. Infarct (DWI), tissue-at-risk (MR-MTT), and final infarct-volume (MR/CT) were manually segmented. DWI images were rated according to the 5-point PIRI-score (“0”=normal, “1”25% is the strongest predictor of large mismatch-loss in this cohort of proximal-MCA occlusive stroke. This outcome marker may help to identify treatment-eligible patients who are in greatest need of rapid reperfusion therapy. PMID:23988643

Kamalian, Shervin; Kemmling, Andre; Borgie, Roderick C; Morais, Livia T; Payabvash, Seyedmehdi; Franceschi, Ana M; Kamalian, Shahmir; Yoo, Albert J; Furie, Karen L; Lev, Michael H

2013-01-01

60

Induced hypertension for the treatment of acute MCA occlusion beyond the thrombolysis window: case report  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background A minority of stroke patients is eligible for thrombolytic therapy. Small pilot case series have hinted that elevation of incident arterial blood pressure might be associated with a favorable prognosis either in acute or subacute stroke. However, these patients were not considered for thrombolytic therapy and were not followed – up systematically. We used pharmacologically induced hypertension in a stroke patient with middle cerebral artery (MCA occlusion ineligible for thrombolysis that was followed-up by radiological, clinical and functional outcome assessment. Case presentation A patient with acute embolic MCA occlusion producing a large, ischemic penumbra confirmed by perfusion CT was treated by induced hypertension with phenylephrine started within 4 h of admission. Increase in the mean arterial pressure by 20% led to a reduction of neurological deficit by 3 points on the National Institute of Stroke Scale. MRI and CT scans performed during phenylephrine infusion showed the presence of limited subcortical and cortical infarct changes that were clearly less extensive than the perfusion deficit in the brain perfusion CT at baseline, found in the absence of MCA patency. No complications due to induced hypertension therapy occurred. Moderate functional improvement up to modified Rankin scale 2 at follow up took place. Conclusion Induced hypertension in acute ischemic stroke seems clinically feasible and may be beneficial in selected normo- or hypotensive stroke patients not eligible for thrombolytic recanalization therapy.

Salonen Oili

2006-12-01

 
 
 
 
61

Plasmodium falciparum Metacaspase PfMCA-1 Triggers a z-VAD-fmk Inhibitable Protease to Promote Cell Death  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Activation of proteolytic cell death pathways may circumvent drug resistance in deadly protozoan parasites such as Plasmodium falciparum and Leishmania. To this end, it is important to define the cell death pathway(s) in parasites and thus characterize proteases such as metacaspases (MCA), which have been reported to induce cell death in plants and Leishmania parasites. We, therefore, investigated whether the cell death function of MCA is conserved in different protozoan parasite species such...

Meslin, Benoi?t; Beavogui, Abdoul H.; Fasel, Nicolas; Picot, Ste?phane

2011-01-01

62

Comparative Analysis of MRAFC Controller MRAC Controller.  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper model reference adaptive based fuzzy controller is presented .Model reference adaptive controller is very common approach to control linear systems, as it is simple to apply. However, the performance of the linear model reference adaptive control weakens up when the system becomes nonlinear. In this paper, the MRAFC has fast learning features and it has good tracking results even when various changes are made in its system parameters. Model reference adaptive control here consists of a fuzzy based controller and a knowledge based modifier. In this paper the plant model and the reference model responses are studied and the error so obtained is being minimized with the help of MRAFC ..The various graphs have been obtained and the study have been done .Results were obtained via simulation software results shows that the MRAFC system has good performance and it can easily adapt to numerous of variations made in the controlled object. .

Swati Mohore

2013-09-01

63

Application Of The Digital Signal Processing Technique For The Design And Construction Of Gamma DSP-Based MCA 8K  

International Nuclear Information System (INIS)

DSP is one of the most useful tools for development of nuclear electronics instruments. The method can be carried out by either a special digital signal processor or FPGA which is programmed through VHDL. In this case, Digital signal processing (DPS) is performed by VHDL code then programing into FPGA device. The aim of this project is to study on digital signal processing technique then application for design and construction of DSP-based MCA 8K. VHDL standards for VHSIC hardware description language. Due to VHDL, almost component such as low pass filter, high pass filter, math function module as adder/subtractor and multiplier, logic control, First In First Out, register, memory and Central processing unit needed for our design can be synthesized and implemented. The VHDL source design has been compiled and implemented by xilinx ISE 10.1 software toolkit and then used to configuration the Spartan XC3S400 device. The main Spartan 3 development board named Siphec XC3S400-TB is used for design of the project. An application software is written in LabVIEW 8.5. The firmware to control the USB interface and interface between FPGA and PC is design in Keil C51 compiler toolkit. (author)

64

Detection of methylation in promoter sequences by melting curve analysis-based semiquantitative real time PCR  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background We present two melting curve analysis (MCA-based semiquantitative real time PCR techniques to detect the promoter methylation status of genes. The first, MCA-MSP, follows the same principle as standard MSP but it is performed in a real time thermalcycler with results being visualized in a melting curve. The second, MCA-Meth, uses a single pair of primers designed with no CpGs in its sequence. These primers amplify both unmethylated and methylated sequences. In clinical applications the MSP technique has revolutionized methylation detection by simplifying the analysis to a PCR-based protocol. MCA-analysis based techniques may be able to further improve and simplify methylation analyses by reducing starting DNA amounts, by introducing an all-in-one tube reaction and by eliminating a final gel stage for visualization of the result. The current study aimed at investigating the feasibility of both MCA-MSP and MCA-Meth in the analysis of promoter methylation, and at defining potential advantages and shortcomings in comparison to currently implemented techniques, i.e. bisulfite sequencing and standard MSP. Methods The promoters of the RASSF1A (3p21.3, BLU (3p21.3 and MGMT (10q26 genes were analyzed by MCA-MSP and MCA-Meth in 13 astrocytoma samples, 6 high grade glioma cell lines and 4 neuroblastoma cell lines. The data were compared with standard MSP and validated by bisulfite sequencing. Results Both, MCA-MSP and MCA-Meth, successfully determined promoter methylation. MCA-MSP provided information similar to standard MSP analyses. However the analysis was possible in a single tube and avoided the gel stage. MCA-Meth proved to be useful in samples with intermediate methylation status, reflected by a melting curve position shift in dependence on methylation extent. Conclusion We propose MCA-MSP and MCA-Meth as alternative or supplementary techniques to MSP or bisulfite sequencing.

Lázcoz Paula

2008-02-01

65

Particle discrimination in water based LiMCA (liquid metal cleanliness analyzer) system  

International Nuclear Information System (INIS)

A mathematical model has been developed to predict the motion of particles in a water based version of the LiMCA system - APS II (Aqueous Particle Sensor) system. The fluid field entering the electric sensing zone (ESZ) was obtained by solving the Navier-Stokes equations and the trajectories of particles by equations for the motion of particles. The results showed that the motions of the particles inside the parabolic shaped orifice are affected by particle density and size. Entrained micro-bubbles lead the fluid flow, travelling faster than latex micro-spheres, which are slightly denser than the fluid and lag only slightly behind the flow. Silica particles, which are much denser than the fluid, lag significantly behind the flow, accelerating more slowly than latex micro-spheres and much more slowly than bubbles. The relative velocities between the entrained particles and the inflowing water decrease with decreasing particle size. The experimental results showed that 1) larger particles have longer transit times than do smaller ones, 2) bubbles have shorter transit times than do latex spheres and much shorter than do silica particles of the same size and 3) differences in transit times are more pronounced for larger particles in keeping with theoretical predictions. The results prove that inclusion discrimination on the basis of density difference is realizable in water based LiMCA systems. (author)

66

Multiscale Modeling and Simulation of Directional Solidification Process of Turbine Blade Casting with MCA Method  

Science.gov (United States)

Nickel-based superalloy turbine blade castings are widely used as a key part in aero engines. However, due to the complex manufacturing processes, the complicated internal structure, and the interaction between different parts of the turbine blade, casting defects, such as stray grains, often happen during the directional solidification of turbine blade castings, which causes low production yield and high production cost. To improve the quality of the directionally solidified turbine blade castings, modeling and simulation technique has been employed to study the microstructure evolution as well as to optimize the casting process. In this article, a modified cellular automaton (MCA) method was used to simulate the directional solidification of turbine blade casting. The MCA method was coupled with macro heat transfer and micro grain growth kinetics to simulate the microstructure evolution during the directional solidification. In addition, a ray tracing method was proposed to calculate the heat transfer, especially the heat radiation of multiple blade castings in a Bridgman furnace. A competitive mechanism was incorporated into the grain growth model to describe the grain selection behavior phenomena of multiple columnar grains in the grain selector. With the proposed models, the microstructure evolution and related defects could be simulated, while the processing parameters optimized and the blade casting quality guaranteed as well. Several experiments were carried out to validate the proposed models, and good agreement between the simulated and experimental results was achieved.

Xu, Qingyan; Zhang, Hang; Qi, Xiang; Liu, Baicheng

2014-04-01

67

Prediction of the outcome of STA-MCA anastomosis by I-123 IMP brain SPECT  

International Nuclear Information System (INIS)

Superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery might improve the cerebral blood flow (CBF), but it does not necessarily mean a good surgical outcome. We estimated the resting CBF and vasoreactivity before and after surgery using I-123 IMP brain SPECT with acetazolamide, and compared them with the surgical outcome. We classified 20 patients into group I (n=10); a post-surgical improvement in CBF>10%, and group II (n=10); an improvement in CBF 10%. The improvement of vasoreactivity was 31.9 ± 19.3% and 28.2 ± 17.2% in groups I and II, respectively (n.s). The improvement of CBF was 20.3 ± 7.7% and 0.9 ± 6.7% in groups I and II, respectively (p<0.001). Post-surgical events were 0 in group I and 4 in II (p<0.05). We concluded that the outcome of STA-MCA bypass surgery would be predictable from the improvement of the resting CBF but not that of vasoreactivity. (author)

68

Morphological component analysis: an adaptive thresholding strategy.  

Science.gov (United States)

In a recent paper, a method called morphological component analysis (MCA) has been proposed to separate the texture from the natural part in images. MCA relies on an iterative thresholding algorithm, using a threshold which decreases linearly towards zero along the iterations. This paper shows how the MCA convergence can be drastically improved using the mutual incoherence of the dictionaries associated to the different components. This modified MCA algorithm is then compared to basis pursuit, and experiments show that MCA and BP solutions are similar in terms of sparsity, as measured by the l1 norm, but MCA is much faster and gives us the possibility of handling large scale data sets. PMID:17990744

Bobin, Jérôme; Starck, Jean-Luc; Fadili, Jalal M; Moudden, Yassir; Donoho, David L

2007-11-01

69

Controllability analysis of decentralised linear controllers for polymeric fuel cells  

Energy Technology Data Exchange (ETDEWEB)

This work deals with the control of polymeric fuel cells. It includes a linear analysis of the system at different operating points, the comparison and selection of different control structures, and the validation of the controlled system by simulation. The work is based on a complex non linear model which has been linearised at several operating points. The linear analysis tools used are the Morari resiliency index, the condition number, and the relative gain array. These techniques are employed to compare the controllability of the system with different control structures and at different operating conditions. According to the results, the most promising control structures are selected and their performance with PI based diagonal controllers is evaluated through simulations with the complete non linear model. The range of operability of the examined control structures is compared. Conclusions indicate good performance of several diagonal linear controllers. However, very few have a wide operability range. (author)

Serra, Maria; Aguado, Joaquin; Ansede, Xavier; Riera, Jordi [Institut de Robotica i Informatica Industrial, Universitat Politecnica de Catalunya - Consejo Superior de Investigaciones Cientificas, C. Llorens i Artigas 4, 08028 Barcelona (Spain)

2005-10-10

70

Pathway kinetics and metabolic control analysis of a high-yielding strain of Penicillium chrysogenum during fed-batch cultivations  

DEFF Research Database (Denmark)

A kinetic model representing the pathway for the biosynthesis of penicillin by P. chrysogenum has been developed. The model is capable of describing the flux through the biosynthetic pathway, and model simulations correspond well with measurements of intermediates and end products. One feature of the present model structure is that it assumes the kinetics of the enzyme isopenicillin N synthetase (IPNS) to be first order with respect to the dissolved oxygen concentration in the range of 0.070 to 0.18 mM (25% to 70% saturation with air). Thus, it indicates the importance that molecular oxygen has on the rate of the reaction catalyzed by this enzyme, and consequently as an enhancer of the specific rate of penicillin production. Using the kinetic model, metabolic control analysis (MCA) of the pathway was performed. The determined flux control coefficients suggested that, during the production phase, the flux is controlled by IPNS as this enzyme becomes saturated with tripeptide delta-(L-alpha-amino-adipyl)-L-cysteinyl-D-valine (LLD-ACV). In the simulations, oxygen was shown to be a bottleneck alleviator by stimulating the rate of IPNS which prevents the accumulation of LLD-ACV. As a consequence of this stimulation, the rate-controlling step was moved to another place in the pathway.

Nielsen, Jens Bredal

1996-01-01

71

Rent control: a comparative analysis  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Recent case law shows that vulnerable, previously disadvantaged private sector tenants are currently facing eviction orders - and consequential homelessness - on the basis that their leases have expired. In terms of the case law it is evident that once their leases have expired, these households do [...] not have access to alternative accommodation. In terms of the Constitution, this group of marginalised tenants have a constitutional right of access to adequate housing and a right to occupy land with legally secure tenure. The purpose of this article is to critically analyse a number of legislative interventions, and specifically rent control, that were imposed in various jurisdictions in order to provide strengthened tenure protection for tenants. The rationale for this analysis is to determine whether the current South African landlord-tenant regime is able to provide adequate tenure protection for vulnerable tenants and therefore in the process of transforming in line with the Constitution. The legal construction of rent control was adopted in pre-1994 South Africa, England and New York City to provide substantive tenure protection for tenants during housing shortages. These statutory interventions in the different private rental markets were justified on the basis that there was a general need to protect tenants against exploitation by landlords. However, the justification for the persistent imposition of rent control in New York City is different since it protects a minority group of financially weak tenants against homelessness. The English landlord-tenant regime highlights the importance of a well-structured social sector that can provide secure, long-term housing options for low-income households who are struggling to access the private rental sector. Additionally, the English rental housing framework shows that if the social sector is functioning as a "safety net" for low-income households, the private sector would be able to uphold deregulation. In light of these comparisons and the fact that the South African social sector is not functioning optimally yet, the question is whether the South African private sector is able to provide the required level of tenure protection for struggling tenants. Recent case law shows that tenants are at liberty to lodge unfair practice complaints with the Rental Housing Tribunals on the basis that the landlords' ground for termination of the lease constitutes an unfair practice. The Court defined an unfair practice as a practice that unreasonably prejudices the tenants' rights or interests. This judicial development signifies some transformation in the private sector since it allows the Tribunals to scrutinise landlords' reasons for termination of tenancies in light of tenants' personal and socioeconomic circumstances. The Tribunals are therefore empowered to weigh the interests of both parties and decide whether to confirm termination of the lease or set aside such termination. In light of this recent development, the Tribunals can provide strengthened tenure protection for destitute tenants on a case by case basis, which incorporates a flexible context-sensitive approach to the provision of secure housing rights in the landlord-tenant framework. This methodology is similar to the German approach. Even though this judicial development is welcomed, it raises some concerns with regard to landlords' property rights and specifically landlords' constitutional property rights since Tribunals are now at liberty to set aside contractually agreed grounds for termination of leases without any statutory guidance. The legislation fails to provide any information regarding legitimate grounds for termination, which might have to be rectified in future. The grounds listed in the rent control legislation should serve as a starting point to determine which grounds for termination of a lease should generally be upheld. However, German landlord-tenant law shows that a statutory ground for termination of a lease shoul

S, Maass.

72

Detection of focal hypoxic-ischemic injury and neuronal stress in a rodent model of unilateral MCA occlusion/reperfusion using radiolabeled annexin V  

International Nuclear Information System (INIS)

In this study we wished to determine whether technetium-99m annexin V, an in vivo marker of cellular injury and death, could be used to noninvasively monitor neuronal injury following focal middle cerebral artery (MCA) occlusion/reperfusion injury. Sixteen adult male Sprague-Dawley rats (along with four controls) underwent left (unilateral) MCA intraluminal beaded thread occlusion for 2 h followed by reperfusion. One hour following tail vein injection of 5-10 mCi of 99mTc-annexin V, animals underwent either single-photon emission computerized tomography (SPECT) or autoradiography followed by immunohistochemical analyses. There was abnormal, bilateral, multifocal uptake of 99mTc-annexin V in each cerebral hemisphere as seen by both SPECT and autoradiography at 4 h and 1, 3, and 7 days after initiation of occlusion. The average maximal annexin V uptake at 4 h was 310%±85% and 365%±151% above control values (P<0.006) within the right and left hemispheres, respectively, peaking on day 3 with values of 925%±734% and 1,194%±643% (P<0.03) that decreased by day 7 to 489%±233% and 785%±225% (P<0.01). Total lesional volume of the left hemisphere was 226%, 261%, and 451% (P<0.03) larger than the right at 4, 24, and 72 h after injury, respectively. Annexin V localized to the cytoplasm of injured neurons ipsilateral to the site of injury as well as to otherwise normal-appearing neurons of the contralateral hemisphere as confirmed by dual fluorescent microscopy. It is concluded that there is abnormal bilateral, multifocal annexin V uptake, greater on the left than on the right side, within 4 h of unilateral left MCA ischemic injury and that the uptake peaks at 3 days and decreases by 7 days after injury. This pattern suggests that neuronal stress may play a role in the response of the brain to focal injury and be responsible for annexin V uptake outside the region of ischemic insult. (orig.)

73

Modular Control Flow Analysis for Libraries  

DEFF Research Database (Denmark)

One problem in analyzing object oriented languages is that the exact control flow graph is not known statically due to dynamic dispatching. However, this is needed in order to apply the large class of known interprocedural analysis. Control Flow Analysis in the object oriented setting aims at determining run-time types of variables, thus allowing to possibly targeted method implementations. We present a flow sensitive analysis that allows separate handling of libraries and thereby efficient analysis of whole programs.

Probst, Christian W.

2002-01-01

74

Multivariable control system analysis of a drum level control system  

International Nuclear Information System (INIS)

It is shown how multivariable analysis and design techniques can be applied effectively to the steam drum level control system of the Prototype Fast Reactor. The drum level control system is shown to be strongly multivariable in nature and as such requires the use of multivariable analysis and design methods. The characteristic locus method was used for the initial analysis. The transmission response method was developed to check these results. The application of multivariable design techniques provided a new insight into the physical behaviour of the system and led to an improved choice of controller parameters for the existing control topology. The design was checked using a detailed simulation model of the whole plant which had been validated against plant data. Simulation results confirmed that the proposed design eliminated drum level oscillations, suffered previously, and yielded significantly better control of drum level during a plant manoeuvre or following disturbances. (author)

75

Quality control analysis at the hospital  

International Nuclear Information System (INIS)

Quality control analysis is an integral part of quality assurance. In a system as with radiopharmaceuticals where part of the finishing of the product takes place at individual hospitals, the need for quality control analysis at the hospital can be discussed. Data are presented that stresses the importance of quality control by the manufacturer as a basis for limitation of such work at hospitals. A simplified programme is proposed

76

Quality control in large sample analysis  

International Nuclear Information System (INIS)

Quality control, as applied in normal activation analysis by the simultaneous analysis of well-characterized quality control samples, blanks and sometimes duplicates, cannot fully be applied in large sample analysis. Well characterized control samples are, e.g., not available at the size of large samples. Different approaches have to be developed to monitor and to control sources of errors in this new type of chemical analysis. Some of the measured sample parameters dealing with gamma-ray and neutron attenuation can only vary between well known values of elemental constants. These parameters can much easier be determined in large sample analysis than with samples in the milligram range, thus offering an outlook for direct verification of the quality of the related correction algorithms. Some examples are given here from experience with the kg-scale neutron activation analysis at the facilities in Delft. (author)

77

Luminescent properties of Eu3+ in MWO4 (M=Ca, Sr, Ba) matrix  

International Nuclear Information System (INIS)

The Eu3+ doped MWO4 (M=Ca, Sr, Ba) phosphors were synthesized via high temperature solid state reaction. The crystal phases of these phosphors were identified by X-ray diffraction. Shifts of the peaks in the structure were observed when Ca2+ sites in the host were completely occupied by the Sr2+ ions or Ba2+ ions. As a result of this replacement, the charge-transfer (CT) band exhibited a blue shift from CaWO4: Eu3+ to SrWO4: Eu3+ and BaWO4: Eu3+. This blue shift could be interpreted with the decreases of the bond covalence between the ligands (L) and the central ion (M) in matrix. In this work, red afterglow originated from the 5D0–7FJ (J=0,1,2,3,4) transitions of Eu3+ could clearly be observed after samples were excited at 254 nm. The thermoluminescence (TL) spectra showed that there were five traps levels in CaWO4: Eu3+ sample and two traps levels in CaWO4: Eu3+ and CaWO4: Eu3+ samples, respectively. The possible explanation of this afterglow phenomenon was also discussed in detail. - Highlights: ? The red afterglow of Eu3+ in MWO4 (M=Sr, Ba) matrix is first observed. ? The blue shift of the charge-transfer band appears and its proposed explanation is discussed. ? The feasible mechanism of the afterhe feasible mechanism of the afterglow is presented.

78

Stray light analysis and control  

CERN Document Server

Stray light is defined as unwanted light in an optical system, a familiar concept for anyone who has taken a photograph with the sun in or near their camera's field of view. This book addresses stray light terminology, radiometry, and the physics of stray light mechanisms, such as surface roughness scatter and ghost reflections. The most-efficient ways of using stray light analysis software packages are included. The book also demonstrates how the basic principles are applied in the design, fabrication, and testing phases of optical system development.

Fest, Eric

2013-01-01

79

Safety Analysis of Control Rod Drive Computers.  

Science.gov (United States)

The analysis of the most significant user programmes revealed no errors in these programmes. The evaluation of approximately 82 cumulated years of operation demonstrated that the operating system of the control rod positioning processor has a reliability ...

W. Ehrenberger, G. Rauch, U. Schmeil, J. Maertz, E. U. Mainka

1985-01-01

80

LANMAS Gap Analysis Report  

Energy Technology Data Exchange (ETDEWEB)

In July, 2000, the Controlled Materials Accountability and Tracking System (COMATS) Team, with the assistance of a representative of the Local Area Network Materials Accountability System (LANMAS) development team from Savannah River, performed an evaluation to enumerate and qualify differences between the current LANMAS functionality and LLNL requirements as implemented by COMATS. The differences found range from minor to serious deficiencies of LANMAS in relation to current LLNL MC&A practice. Therefore, we recommend a gradual integration of LANMAS into a hybrid system which uses LANMAS to satisfy DOE/NNSA MC&A and reporting requirements and uses COMATS to satisfy LLNL-specific MC&A and operational requirements.

Parrish, C.; Yee, W.; Okuda, V.; Watson, B.; Storch, N

2000-08-25

 
 
 
 
81

Preoperative cerebral perfusion SPECT identify patients at risk for transient neurological deterioration after STA-MCA bypass surgery  

Energy Technology Data Exchange (ETDEWEB)

Transient neurological deterioration (TND) is one of the most fatal complications after extracranial-intracranial bypass surgery and it has been assumed to be caused by transient hyperperfusion. This study was performed to evaluate the relationship between TND and preoperative cerebral perfusion status on brain SPECT to identify patients who are at risk of TND following superficial temporal artery middle cerebral artery (STA-MCA) bypass surgery. Sixty patients who underwent STA-MCA bypass surgery were enrolled. The resting cerebral blood flow (CBF) and cerebral vascular reserve (CVR) after acetazolamide challenge were measured before and 10 days after surgery using Tc-99m ethylcysteinate dimmer SPECT. Moreover, the CBF was measured on the third day postoperation. Follow up perfusion SPECT 6 month after surgery were obtained in 42 patients. With the use of the statistical parametric mapping and probabilistic brain atlas, the counts for the MCA territory were calculated for each image and statistical analyses were performed. In 6 of 60 patients (10%), TND occurred after surgery. The average CBF on the third postoperative day was significantly higher than the preoperative CBF (p 0.003). Furthermore, in 42 patients who had brain SPECT in the 6 months following operation, cerebral perfusion in the 6 months post operation was still higher than that observed before the operation. The increase in CBF from the preoperative day to the third postoperative day negatively correlated with preoperative perfusion (correlation coefficient = -0.66, p 0.0006). In TND patients, basal CBF on preoperative SPECT was significantly lower (p=0.01), and the changes in CBF on the third day after surgery was significant higher (p = 0.008). However, CVR did not significantly correlate with the increased perfusion after operation. The preoperative CBF and the subsequent changes in CBF after operation can help identify the risk of TND after STA-MCA bypass surgery.

Lee, J. W.; Kim, Y. K.; Eo, J. S.; Oh, C. W.; Lee, W. W.; Kim, S. W. [Seoul National University Bundang Hospital, Bundang (Korea, Republic of)

2007-07-01

82

A Report on the Mock Interviews Conducted for Students of MCA IV Semester in April 2011 at the ELTC  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A mock interview was conducted for students of MCA IV Semester, University of Hyderabad on 9, 10 Apr-2011 with the help of the management and experts from outside. The Interview panel assessed the technical and communication competence of the students and gave them individual and group feedback on their performances. Students found it to be a good rehearsal for actual job interview. it was treated as a part of placement related training and continuous assessment of the students during the cou...

Aruna Lolla

2012-01-01

83

Pharmacological Effects of the Ruthenium Complex NAMI-A Given Orally to CBA Mice With MCa Mammary Carcinoma  

Digital Repository Infrastructure Vision for European Research (DRIVER)

NAMI-A, imidazolium trans-imidazoledimethylsulfoxidetetrachlororuthenate, is a ruthenium based compounds capable of inhibiting the growth of lung metastases of solid tumours in a number of experimental conditions.The aim of this study was to investigate the potential use of NAMI-A by the oral route to treat lung metastases of MCa mammary carcinoma in the CBA mouse. treatment of mice, carrying intramuscular tumours in advanced stage of growth, for 11 consecutive days caused a signi...

Zorzet, Sonia; Sorc, Alenka; Casarsa, Claudia; Cocchietto, Moreno; Sava, Gianni

2001-01-01

84

Preparation and photoluminescence properties of Mn2+-activated M2Si5N8 (M=Ca, Sr, Ba) phosphors  

International Nuclear Information System (INIS)

Mn2+-doped M2Si5N8 (M=Ca, Sr, Ba) phosphors have been prepared by a solid-state reaction method at high temperature and their photoluminescence properties were investigated. The Mn2+-activated M2Si5N8 phosphors exhibit narrow emission bands in the wavelength range of 500-700 nm with peak center at about 599, 606 and 567 nm for M=Ca, Sr, Ba, respectively, due to the 4T1(4G)?6A1(6S) transition of Mn2+. The long-wavelength emission of Mn2+ ion in the host of M2Si5N8 is attributed to the effect of a strong crystal-field of Mn2+ in the nitrogen coordination environment. Also it is observed that there exists energy transfer between M2Si5N8 host lattice and activator (Mn2+). The potential applications of these phosphors have been pointed out. - Graphical abstract: The luminescence properties of Mn2+ in M2Si5N8 (M=Ca, Sr, Ba) have been investigated. All M2Si5N8:Mn2+ phosphors show narrow symmetric bands in the wavelength range of 500-700 nm with peak center at about 599, 606 and 567 nm for M=Ca, Sr, Ba, respectively. The observed band emission is ascribed to the 4T1(4G)?6A14G)?6A1(6S) transition of Mn2+ in M2Si5N8 host lattice

85

Orion Orbit Control Design and Analysis  

Science.gov (United States)

The analysis of candidate thruster configurations for the Crew Exploration Vehicle (CEV) is presented. Six candidate configurations were considered for the prime contractor baseline design. The analysis included analytical assessments of control authority, control precision, efficiency and robustness, as well as simulation assessments of control performance. The principles used in the analytic assessments of controllability, robustness and fuel performance are covered and results provided for the configurations assessed. Simulation analysis was conducted using a pulse width modulated, 6 DOF reaction system control law with a simplex-based thruster selection algorithm. Control laws were automatically derived from hardware configuration parameters including thruster locations, directions, magnitude and specific impulse, as well as vehicle mass properties. This parameterized controller allowed rapid assessment of multiple candidate layouts. Simulation results are presented for final phase rendezvous and docking, as well as low lunar orbit attitude hold. Finally, on-going analysis to consider alternate Service Module designs and to assess the pilot-ability of the baseline design are discussed to provide a status of orbit control design work to date.

Jackson, Mark; Gonzalez, Rodolfo; Sims, Christopher

2007-01-01

86

Effect of STA-MCA bypass for ocular ischemic syndrome due to occlusive internal carotid artery diseases  

International Nuclear Information System (INIS)

The authors examined the effect of superficial temporal artery-middle cerebral artery (STA-MCA) bypass for chronic ocular ischemic syndrome (OIS) due to occlusive internal carotid artery (ICA) diseases. We retrospectively examined the result of STA-MCA bypass in 49 patients with chronic OIS due to occlusive ICA diseases. Symptoms were a decline in visual acuity in 32 patients, frequent amaurosis fugax in 8 patients, and 9 patients showed both symptoms. Preoperatively, the flow directions of the ophthalmic artery were reversed in 45 patients and antegrade in 4 patients. The average peak systolic flow velocity (PFV) of the ophthalmic artery was -0.37 m/sec. At one month after bypass, 17 patients showed the antegrade ophthalmic artery flow. Mean PFV of the ophthalmic artery significantly rose to -0.12 m/sec (p<0.05). At three months after surgery, 26 patients showed the antegrade flow. Mean PFV of the ophthalmic artery significantly increased to 0.01 m/sec (p<0.05). During the follow-up period (mean 4.9 years), visual acuity improved in 23 patients (47%) and ceased to worsen in the remaining 26 patients. STA-MCA bypass was useful in improving and preventing OIS due to occlusive ICA diseases. (author)

87

Development of a robotized sample changing system for activation analysis  

International Nuclear Information System (INIS)

An automatic sample changing system with a small robot has been developed and constructed for instrumental neutron activation analysis (INAA). The developed system composed of a model A151 small robot (CRS Plus Inc., Canada), a NEC PC-980m2 personal computer having two of 1 Mbyte floppy-disk drivers, a NAIG NLAB-MCA multichannel analyzer (Toshiba), Ge detector settled in a low background shield and a tray stored 20 dishes containing a sample. The robot has a five-axis articulated arm (reach: 560 mm, payload: 2 kg, speed: 17 m/s, repeatability: 0.13 mm, weight: 17 kg). The robot and the multichannel analyzer (MCA) are controlled by the personal computer via RS-232C or GP-IB interface. (author)

88

Preliminary analysis on plasma equilibrium control  

International Nuclear Information System (INIS)

Survey of the plasma experiments about dependence of plasma confinement on plasma shaping, prescription of the space state equation for plasma shape control using MHD equilibrium equation and analysis of steady state deformation of plasma cross sectional shape due to plasma parameter disturbances were caried out for the shake of preliminary study of plasma equilibrium control in the Fusion Experimental Reactor (FER). Experiments so far showed that it is desirable to control plasma surface position within 1 cm error, but the analysis here showed that possible disturbance may shift it by 2 - 3 cm and it is difficult to control plasma whole surface in good accuracy only with the plasma position control coils which is placed at the inner area of the toroidal coils. (author)

89

Aircraft Loss-of-Control Accident Analysis  

Science.gov (United States)

Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. To gain a better understanding into aircraft loss-of-control events and possible intervention strategies, this paper presents a detailed analysis of loss-of-control accident data (predominantly from Part 121), including worst case combinations of causal and contributing factors and their sequencing. Future potential risks are also considered.

Belcastro, Christine M.; Foster, John V.

2010-01-01

90

Temperature analysis of control rod for HTTR  

International Nuclear Information System (INIS)

For the High Temperature Engineering Test Reactor, the reactor shut down from the high temperature condition is made by the two-step control rods insertion in order to avoid a fatigue damage of control rod casing at high temperature. The control rods in reflector region are inserted into the core immediately after reactor scram and then, the control rods in fuel region are inserted when the core temperature becomes enough lower than the temperature limit of materials. Control rods in fuel region are inserted automatically by either signal of prescribed time given by timers or the signal that reactor outlet coolant temperature reached the preset value. This report describes the method, condition and results of control rod temperature analysis under various scram conditions. (author)

91

Analysis and control of underactuated mechanical systems  

CERN Document Server

This monograph provides readers with tools for the analysis, and control of systems with fewer control inputs than degrees of freedom to be controlled, i.e., underactuated systems. The text deals with the consequences of a lack of a general theory that would allow methodical treatment of such systems and the ad hoc approach to control design that often results, imposing a level of organization whenever the latter is lacking. The authors take as their starting point the construction of a graphical characterization or control flow diagram reflecting the transmission of generalized forces through the degrees of freedom. Underactuated systems are classified according to the three main structures by which this is found to happen—chain, tree, and isolated vertex—and control design procedures proposed. The procedure is applied to several well-known examples of underactuated systems: acrobot; pendubot; Tora system; ball and beam; inertia wheel; and robotic arm with elastic joint. The text is illustrated with MATL...

Choukchou-Braham, Amal; Djemaï, Mohamed; Busawon, Krishna

2014-01-01

92

ASTEC: Controls analysis for personal computers  

Science.gov (United States)

The ASTEC (Analysis and Simulation Tools for Engineering Controls) software is under development at Goddard Space Flight Center (GSFC). The design goal is to provide a wide selection of controls analysis tools at the personal computer level, as well as the capability to upload compute-intensive jobs to a mainframe or supercomputer. The project is a follow-on to the INCA (INteractive Controls Analysis) program that has been developed at GSFC over the past five years. While ASTEC makes use of the algorithms and expertise developed for the INCA program, the user interface was redesigned to take advantage of the capabilities of the personal computer. The design philosophy and the current capabilities of the ASTEC software are described.

Downing, John P.; Bauer, Frank H.; Thorpe, Christopher J.

1989-01-01

93

Analysis and design of hybrid control systems  

Energy Technology Data Exchange (ETDEWEB)

Different aspects of hybrid control systems are treated: analysis, simulation, design and implementation. A systematic methodology using extended Lyapunov theory for design of hybrid systems is developed. The methodology is based on conventional control designs in separate regions together with a switching strategy. Dynamics are not well defined if the control design methods lead to fast mode switching. The dynamics depend on the salient features of the implementation of the mode switches. A theorem for the stability of second order switching together with the resulting dynamics is derived. The dynamics on an intersection of two sliding sets are defined for two relays working on different time scales. The current simulation packages have problems modeling and simulating hybrid systems. It is shown how fast mode switches can be found before or during simulation. The necessary analysis work is a very small overhead for a modern simulation tool. To get some experience from practical problems with hybrid control the switching strategy is implemented in two different software environments. In one of them a time-optimal controller is added to an existing PID controller on a commercial control system. Successful experiments with this hybrid controller shows the practical use of the method 78 refs, 51 figs, 2 tabs

Malmborg, J.

1998-05-01

94

TARA control, data acquisition and analysis system  

International Nuclear Information System (INIS)

The MIT tandem mirror (TARA) control, data acquisition and analysis system consists of two major parts: (1) a Gould 584 industrial programmable controller (PC) to control engineering functions; and (2) a VAX 11/750 based data acquisition and analysis system for physics analysis. The PC is designed for use in harsh industrial environments and has proven to be a reliable and cost-effective means for automated control. The PC configuration is dedicated to control tasks on the TARA magnet, vacuum, RF, neutral beam, diagnostics, and utility systems. The data transfer functions are used to download system operating parameters from menu selectable tables. Real time status reports are provided to video terminals and as blocks of data to the host computer for storage. The data acquisition and analysis system for TARA was designed to provide high throughput and ready access to data from earlier runs. The adopted design uses pre-existing software packages in a system which is simple, coherent, fast, and which requires a minimum of new software development. The computer configuration is a VAX 11/750 running VMS with 124 M byte massbus disk and 1.4 G byte unibus disk subsystem

95

78 FR 79328 - Amendments to Material Control and Accounting Regulations and Proposed Guidance for Fuel Cycle...  

Science.gov (United States)

...Amendments to Material Control and Accounting Regulations and Proposed Guidance...Facility Material Control and Accounting Plans and Completing the U...guidance on material control and accounting (MC&A) of special...

2013-12-30

96

78 FR 71532 - Amendments to Material Control and Accounting Regulations and Proposed Guidance for Fuel Cycle...  

Science.gov (United States)

...Amendments to Material Control and Accounting Regulations and Proposed Guidance...Facility Material Control and Accounting Plans and Completing the U...regulations for material control and accounting (MC&A) of special...

2013-11-29

97

Tracker Video Analysis: Remote Control Helicopter  

Science.gov (United States)

How much can a remote control helicopter lift? The video analysis in this item explores the physics behind a toy helicopter. The zip file contains the Dot Physics blog entry, a video of the flying helicopter, and a Tracker video analysis file. A discussion of helicopter physics was posted on the Dot Physics blog for Wired. To open the Tracker file, download and run Tracker from http://www.cabrillo.edu/~dbrown/tracker/. Tracker is free.

Allain, Rhett J.

2012-04-30

98

Revealing the translation control by transcriptome analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Taking the eukaryotic translation initiation factor 5A (eIF5A asmodel, some aspects of different points of gene expression controland transcriptome studies are discussed. A parallel with proteomicstudies is presented, as well as the optimization of thetranscriptome analysis using polysome profile assay. The polysomeprofile assay application reveals the translational control of mRNAsnot identified by traditional differential analysis of transcriptomes,which is widely employed to study diseases, such as tumors.

Augusto Ducati Luchessi

2006-09-01

99

Applied behavior analysis and statistical process control?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper examines Pfadt and Wheeler's (1995) suggestions that the methods of statistical process control (SPC) be incorporated into applied behavior analysis. The research strategies of SPC are examined and compared to those of applied behavior analysis. I argue that the statistical methods that are a part of SPC would likely reduce applied behavior analysts' intimate contacts with the problems with which they deal and would, therefore, likely yield poor treatment and research decisions. Ex...

Hopkins, B. L.

1995-01-01

100

Safety analysis of control rod drive computers  

International Nuclear Information System (INIS)

The analysis of the most significant user programmes revealed no errors in these programmes. The evaluation of approximately 82 cumulated years of operation demonstrated that the operating system of the control rod positioning processor has a reliability that is sufficiently good for the tasks this computer has to fulfil. Computers can be used for safety relevant tasks. The experience gained with the control rod positioning processor confirms that computers are not less reliable than conventional instrumentation and control system for comparable tasks. The examination and evaluation of computers for safety relevant tasks can be done with programme analysis or statistical evaluation of the operating experience. Programme analysis is recommended for seldom used and well structured programmes. For programmes with a long, cumulated operating time a statistical evaluation is more advisable. The effort for examination and evaluation is not greater than the corresponding effort for conventional instrumentation and control systems. This project has also revealed that, where it is technologically sensible, process controlling computers or microprocessors can be qualified for safety relevant tasks without undue effort. (orig./HP)

 
 
 
 
101

Analysis of feedback control of piezoelectric transducers.  

Science.gov (United States)

Velocity control feedback may be required for implementation in large underwater acoustic arrays to mitigate the effects of strong acoustic field coupling when specific beam pattern performance over a variety of operating conditions is desired. This paper presents an analysis of velocity control with piezoelectric loads using motional current monitoring [as an extension to Aronov, J. Acoust. Soc. Am. 119(6), 3822-3830 (2006) and Bachand, Brown, and Aronov, J. Acoust. Soc. Am. 124(4), 2568 (2008)], with particular interest in automated wideband acoustic beamforming. The analysis is applicable to other forms of motional feedback control such as accelerometer or displacement signal feedback. Topics presented include the control loop's effectiveness, stability criteria, and the array equations governing the acoustical outputs. The conditions that can cause negative radiation impedance are also presented, concluding that in any velocity control system with acoustic interactions, the likelihood of a transmit channel absorbing more energy than it is transmitting increases with the feedback loop gain. This fundamental limitation must be considered before developing any practical acoustic velocity control system with strong inter-element acoustic field coupling. PMID:24907806

Randall, Robert C; Brown, David A

2014-06-01

102

Financial Analysis, Budgeting, Decision and Control  

Directory of Open Access Journals (Sweden)

Full Text Available The economic processes taking place in the economic environment are stochastic processes that involve and imply risks, arising from product diversification, competition, financial derivatives transactions: swaps, futures, options and from the large number of actors involved in the stock market with a higher or a smaller uncertainty degree. Competition and competitiveness, led to major and rapid change in the business environment, they determined actors participating in the economy to find solutions and methods of collecting and processing data, in such a way that, after being transformed into information they quickly help based on their analysis in decision making, planning and financial forecasting, having an effect on increasing their economic efficiency. In these circumstances the financial analysis, decision, forecasting and control, should be based on quality information that should be a value creation source. The active nature of the financial function implies the existence of a substantially large share of financial analysis, financial decision, forecasting and control.

Mariana Rodica TIRLEA

2013-12-01

103

A Report on the Mock Interviews Conducted for Students of MCA IV Semester in April 2011 at the ELTC  

Directory of Open Access Journals (Sweden)

Full Text Available A mock interview was conducted for students of MCA IV Semester, University of Hyderabad on 9, 10 Apr-2011 with the help of the management and experts from outside. The Interview panel assessed the technical and communication competence of the students and gave them individual and group feedback on their performances. Students found it to be a good rehearsal for actual job interview. it was treated as a part of placement related training and continuous assessment of the students during the course.

Aruna Lolla

2012-02-01

104

10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...  

Science.gov (United States)

...Accounting (MC&A) system must include the...A measurement systems are controlled...and resolving, or reporting an inability to...inventory; (5) A detection program, independent...more in the U235 isotope, to the extent...effectiveness of the MC&A system at least every...

2010-01-01

105

Evaluating control displays with the Engineering Control Analysis Tool (ECAT)  

Energy Technology Data Exchange (ETDEWEB)

In the Nuclear Power Industry increased use of automated sensors and advanced control systems is expected to reduce and/or change manning requirements. However, critical questions remain regarding the extent to which safety will be compromised if the cognitive workload associated with monitoring multiple automated systems is increased. Can operators/engineers maintain an acceptable level of performance if they are required to supervise multiple automated systems and respond appropriately to off-normal conditions? The interface to/from the automated systems must provide the information necessary for making appropriate decisions regarding intervention in the automated process, but be designed so that the cognitive load is neither too high nor too low for the operator who is responsible for the monitoring and decision making. This paper will describe a new tool that was developed to enhance the ability of human systems integration (HSI) professionals and systems engineers to identify operational tasks in which a high potential for human overload and error can be expected. The tool is entitled the Engineering Control Analysis Tool (ECAT). ECAT was designed and developed to assist in the analysis of: Reliability Centered Maintenance (RCM), operator task requirements, human error probabilities, workload prediction, potential control and display problems, and potential panel layout problems. (authors)

Plott, B. [Alion Science and Technology, MA and D Operation, 4949 Pearl E. Circle, 300, Boulder, CO 80301 (United States)

2006-07-01

106

Evaluating control displays with the Engineering Control Analysis Tool (ECAT)  

International Nuclear Information System (INIS)

In the Nuclear Power Industry increased use of automated sensors and advanced control systems is expected to reduce and/or change manning requirements. However, critical questions remain regarding the extent to which safety will be compromised if the cognitive workload associated with monitoring multiple automated systems is increased. Can operators/engineers maintain an acceptable level of performance if they are required to supervise multiple automated systems and respond appropriately to off-normal conditions? The interface to/from the automated systems must provide the information necessary for making appropriate decisions regarding intervention in the automated process, but be designed so that the cognitive load is neither too high nor too low for the operator who is responsible for the monitoring and decision making. This paper will describe a new tool that was developed to enhance the ability of human systems integration (HSI) professionals and systems engineers to identify operational tasks in which a high potential for human overload and error can be expected. The tool is entitled the Engineering Control Analysis Tool (ECAT). ECAT was designed and developed to assist in the analysis of: Reliability Centered Maintenance (RCM), operator task requirements, human error probabilities, workload prediction, potential control and display problems, and potential panel layout problems. (authors)

107

Analysis and control of distributed cooperative systems.  

Energy Technology Data Exchange (ETDEWEB)

As part of DARPA Information Processing Technology Office (IPTO) Software for Distributed Robotics (SDR) Program, Sandia National Laboratories has developed analysis and control software for coordinating tens to thousands of autonomous cooperative robotic agents (primarily unmanned ground vehicles) performing military operations such as reconnaissance, surveillance and target acquisition; countermine and explosive ordnance disposal; force protection and physical security; and logistics support. Due to the nature of these applications, the control techniques must be distributed, and they must not rely on high bandwidth communication between agents. At the same time, a single soldier must easily direct these large-scale systems. Finally, the control techniques must be provably convergent so as not to cause undo harm to civilians. In this project, provably convergent, moderate communication bandwidth, distributed control algorithms have been developed that can be regulated by a single soldier. We have simulated in great detail the control of low numbers of vehicles (up to 20) navigating throughout a building, and we have simulated in lesser detail the control of larger numbers of vehicles (up to 1000) trying to locate several targets in a large outdoor facility. Finally, we have experimentally validated the resulting control algorithms on smaller numbers of autonomous vehicles.

Feddema, John Todd; Parker, Eric Paul; Wagner, John S.; Schoenwald, David Alan

2004-09-01

108

Statistical quality control through overall vibration analysis  

Science.gov (United States)

The present study introduces the concept of statistical quality control in automotive wheel bearings manufacturing processes. Defects on products under analysis can have a direct influence on passengers' safety and comfort. At present, the use of vibration analysis on machine tools for quality control purposes is not very extensive in manufacturing facilities. Noise and vibration are common quality problems in bearings. These failure modes likely occur under certain operating conditions and do not require high vibration amplitudes but relate to certain vibration frequencies. The vibration frequencies are affected by the type of surface problems (chattering) of ball races that are generated through grinding processes. The purpose of this paper is to identify grinding process variables that affect the quality of bearings by using statistical principles in the field of machine tools. In addition, an evaluation of the quality results of the finished parts under different combinations of process variables is assessed. This paper intends to establish the foundations to predict the quality of the products through the analysis of self-induced vibrations during the contact between the grinding wheel and the parts. To achieve this goal, the overall self-induced vibration readings under different combinations of process variables are analysed using statistical tools. The analysis of data and design of experiments follows a classical approach, considering all potential interactions between variables. The analysis of data is conducted through analysis of variance (ANOVA) for data sets that meet normality and homoscedasticity criteria. This paper utilizes different statistical tools to support the conclusions such as chi squared, Shapiro-Wilks, symmetry, Kurtosis, Cochran, Hartlett, and Hartley and Krushal-Wallis. The analysis presented is the starting point to extend the use of predictive techniques (vibration analysis) for quality control. This paper demonstrates the existence of predictive variables (high-frequency vibration displacements) that are sensible to the processes setup and the quality of the products obtained. Based on the result of this overall vibration analysis, a second paper will analyse self-induced vibration spectrums in order to define limit vibration bands, controllable every cycle or connected to permanent vibration-monitoring systems able to adjust sensible process variables identified by ANOVA, once the vibration readings exceed established quality limits.

Carnero, M. a. Carmen; González-Palma, Rafael; Almorza, David; Mayorga, Pedro; López-Escobar, Carlos

2010-05-01

109

TARA control, data acquisition and analysis system  

International Nuclear Information System (INIS)

The TARA control, data acquisition and analysis system consists of two major parts: (1) a Gould 584 industrial programmable controller (PC); (2) a VAX 11/750 based data acquisition and analysis system. The PC is designed for use in harsh industrial environments and has proven to be a reliable and cost-effective means for automated control. The PC configuration is dedicated to control tasks on the TARA magnet, vacuum, RF, neutral beam, diagnostics, and utility systems. The data transfer functions are used to download system operating parameters from menu selectable tables. Real time status reports are provided to video terminals and as blocks of data to the host computer for storage. The data acquisition and analysis system for TARA was designed to provide a high throughput and ready access to data from earlier runs. The adopted design uses pre-existing software packages in a system which is simple, coherent, fast and which requires a minimum of new software development. The computer configuration is a VAX 11/750 running VMS with 124 M BYTE massbuss disk and 1.4 G BYTE unibus disk subsystem. The front end for the data is a kinetic systems camac serial highway interface, and the graphics I/0 is done through a DMA terminal multiplexer. The data system provides a set of standard tools for use in user-written analysis programs. These tools allow access to current shot data as well as past shots with a minimum of overhead. The acquisition, archival, basic analysis, and display of 1 M BYTE of data for every shot is accomplished once each 3 to 5 minutes, and any shot may be easily reanalyzed

110

Quantitative resilience analysis through control design.  

Energy Technology Data Exchange (ETDEWEB)

Critical infrastructure resilience has become a national priority for the U. S. Department of Homeland Security. System resilience has been studied for several decades in many different disciplines, but no standards or unifying methods exist for critical infrastructure resilience analysis. Few quantitative resilience methods exist, and those existing approaches tend to be rather simplistic and, hence, not capable of sufficiently assessing all aspects of critical infrastructure resilience. This report documents the results of a late-start Laboratory Directed Research and Development (LDRD) project that investigated the development of quantitative resilience through application of control design methods. Specifically, we conducted a survey of infrastructure models to assess what types of control design might be applicable for critical infrastructure resilience assessment. As a result of this survey, we developed a decision process that directs the resilience analyst to the control method that is most likely applicable to the system under consideration. Furthermore, we developed optimal control strategies for two sets of representative infrastructure systems to demonstrate how control methods could be used to assess the resilience of the systems to catastrophic disruptions. We present recommendations for future work to continue the development of quantitative resilience analysis methods.

Sunderland, Daniel; Vugrin, Eric D.; Camphouse, Russell Chris (Sandia National Laboratories, Carlsbad, NM)

2009-09-01

111

Analysis and control of Boolean networks  

CERN Document Server

""Analysis and Control of Boolean Networks"" presents a systematic new approach to the investigation of Boolean control networks. The fundamental tool in this approach is a novel matrix product called the semi-tensor product (STP). Using the STP, a logical function can be expressed as a conventional discrete-time linear system. In the light of this linear expression, certain major issues concerning Boolean network topology - fixed points, cycles, transient times and basins of attractors - can be easily revealed by a set of formulae. This framework renders the state-space approach to dynamic co

Cheng, Daizhan; Li, Zhiqiang

2010-01-01

112

Practical implementation of survey analysis in inductively coupled plasma optical emission spectrometry  

Science.gov (United States)

The combination of an echelle/charge coupled device detector based spectrometer with software for multicomponent analysis (MCA) allows practical implementation of survey analysis in inductively coupled plasma-optical emission spectrometry (ICP-OES). MCA requires models for the pure components. A procedure is described for how to obtain the models for 67 pure elements detectable in ICP-OES. In fact, each element is represented by two model vectors. Measurements at low analyte concentration provide the sensitivities for the prominent lines used in trace analysis, whereas weak lines and continuum emission are modelled with high concentration measurements. This modelling allows proper calibration for trace and major levels, and strongly reduces noise contributions. The model library is prepared once and a monitor solution, containing seven specific elements, is used to achieve a daily link with this once-only calibration (wavelength axis and sensitivity). To control the efficiency of atomization and ionization the Cr II 267 nm to Cr I 357 nm ratio is used. The MCA calculations are repeated at different intensity levels in order to cover the dynamic range in intensity and, hence, concentration for all the elements present in the sample solution. Matrix-matching of the monitor solution was studied in order to overcome matrix effects owing to high acid or salt contents. Some certified reference materials were analysed. The results for most elements are found within 20% of the certified values.

Morales, J. A.; van Veen, E. H.; de Loos-Vollebregt, M. T. C.

1998-05-01

113

Ivy signs on FLAIR images before and after STA-MCA anastomosis in patients with Moyamoya disease  

International Nuclear Information System (INIS)

Background: Leptomeningeal high signal intensity (ivy sign) on fluid-attenuated inversion-recovery (FLAIR) MR imaging is one of the features of Moyamoya disease. However, the correlation between ivy sign and cerebral perfusion status has not been fully evaluated. Purpose: To characterize ivy sign on FLAIR images in Moyamoya disease and compare this finding with hemodynamic alterations on perfusion single-photon emission CT (SPECT) obtained before and after bypass surgery. Material and Methods: Sixteen patients with angiographically confirmed Moyamoya disease who underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis were included in the study. The presence of ivy sign on FLAIR images was classified as 'negative', 'minimal' and 'positive'. We evaluated the relationship between ivy sign and findings of SPECT, including cerebral vascular reserve (CVR) before and after surgery. Results: Minimal or positive ivy sign was seen in 13 (81%) of 16 patients, and 21 (66%) of 32 hemispheres. CVR in the areas with positive or minimal ivy sign was lower than that in the areas with negative ivy sign. After STA-MCA anastomosis, ivy sign disappeared or decreased in all 21 hemispheres demonstrating ivy sign. SPECT demonstrated apparent hemodynamic improvement in areas demonstrating disappearance or decrease of ivy sign. Conclusion: Ivy sign on FLAIR image is seen in areas with decreased cerebral perfusion. The sign is useful for non-invasive assessment of cer useful for non-invasive assessment of cerebral hemodynamic status before and after surgery

114

PROMETHEE Method and Sensitivity Analysis in the Software Application for the Support of Decision-Making  

Directory of Open Access Journals (Sweden)

Full Text Available PROMETHEE is one of methods, which fall into multi-criteria analysis (MCA. The MCA, as the name itself indicates, deals with the evaluation of particular variants according to several criteria. Developed software application (MCA8 for the support of multi-criteria decision-making was upgraded about PROMETHEE method and a graphic tool, which enables the execution of the sensitivity analysis. This analysis is used to ascertain how a given model output depends upon the input parameters. The MCA8 software application with mentioned graphic upgrade was developed for purposes of solving multi-criteria decision tasks. In the MCA8 is possible to perform sensitivity analysis by a simple form – through column graphs. We can change criteria significances (weights in these column graphs directly and watch the changes of the order of variants immediately.

Petr Moldrik

2008-01-01

115

Multi-channel analyzer controlled by applet and flash  

International Nuclear Information System (INIS)

Both java applet and flash were applied to emulate virtual panel of multi-channel pulse height analyzer (MCA), and Microsoft IE browser was used to control MCA through internet to measure the ?-ray energy spectrum of 137Cs. It was shown that most of the work completed by applet can be done by flash too, and with flash, more beautiful panel of the remote controlled instruments can be easily designed

116

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.  

Science.gov (United States)

...Hazard Analysis Critical Control Point (HACCP) plan. 123.6 Section 123.6 ...Hazard Analysis Critical Control Point (HACCP) plan. (a) Hazard analysis...absence of those controls. (b) The HACCP plan. Every processor shall have...

2010-04-01

117

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.  

Science.gov (United States)

...Drugs 2 2010-04-01 2010-04-01 false Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan...FISHERY PRODUCTS General Provisions § 123.6 Hazard analysis and Hazard Analysis Critical Control...

2010-04-01

118

Studying On Digital Signal Processing Method For Tested Design And The Construction Of DSP-Based MCA 1K  

International Nuclear Information System (INIS)

DSP is one of the most useful tools for development of nuclear electronics instruments for Physics research. The method can be carried out by either a special digital signal processor or FPGA which is programmed through VHDL. In this case, Digital signal processing (DPS) is performed by VHDL. The aim of this project is to study on digital signal processing for tested design and construction of DSP-based MCA 1K. VHDL standards for VHSIC hardware description language. Due to VHDL, memory and Central processing unit are created. An application software for receiving data is written in LabVIEW 8.5. Spartan 3E starter kit is used for design of the project, combining with ISE software, XilinX 9.2i. (author)

119

Intensive post-operative follow-up of breast cancer patients with tumour markers: CEA, TPA or CA15.3 vs MCA and MCA-CA15.3 vs CEA-TPA-CA15.3 panel in the early detection of distant metastases  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background In breast cancer current guidelines do not recommend the routine use of serum tumour markers. Differently, we observed that CEA-TPA-CA15.3 (carcinoembryonic (CEA tissue polypeptide (TPA and cancer associated 115D8/DF3 (CA15.3 antigens panel permits early detection and treatment for most relapsing patients. As high sensitivity and specificity and different cut-off values have been reported for mucin-like carcinoma associated antigen (MCA, we compared MCA with the above mentioned tumour markers and MCA-CA15.3 with the CEA-TPA-CA15.3 panel. Methods In 289 breast cancer patients submitted to an intensive post-operative follow-up with tumour markers, we compared MCA (cut-off values, ? 11 and ? 15 U/mL with CEA or CA15.3 or TPA for detection of relapse. In addition, we compared the MCA-CA15.3 and CEA-TPA-CA15.3 tumour marker panels. Results Distant metastases occurred 19 times in 18 (6.7% of the 268 patients who were disease-free at the beginning of the study. MCA sensitivity with both cut-off values was higher than that of CEA or TPA or CA15.3 (68% vs 10%, 26%, 32% and 53% vs 16%, 42%, 32% respectively. With cut-off ? 11 U/mL, MCA showed the lowest specificity (42%; with cut-off ? 15 U/mL, MCA specificity was similar to TPA (73% vs 72% and lower than that of CEA and CA15.3 (96% and 97% respectively. With ? 15 U/mL MCA cut-off, MCA sensitivity increased from 53% to 58% after its association with CA15.3. Sensitivity of CEA-TPA-CA15.3 panel was 74% (14 of 19 recurrences. Eight of the 14 recurrences early detected with CEA-TPA-CA15.3 presented as a single lesion (oligometastatic disease (5 or were confined to bony skeleton (3 (26% and 16% respectively of the 19 relapses. With ? 11 U/mL MCA cut-off, MCA-CA15.3 association showed higher sensitivity but lower specificity, accuracy and positive predictive value than the CEA-TPA-CA15.3 panel. Conclusion At both the evaluated cut-off values serum MCA sensitivity is higher than that of CEA, TPA or CA15.3 but its specificity is similar to or lower than that of TPA. Overall, CEA-TPA-CA15.3 panel is more accurate than MCA-CA15.3 association and can "early" detect a few relapsed patients with limited metastatic disease and more favourable prognosis. These findings further support the need for prospective randomised clinical trial to assess whether an intensive post-operative follow-up with an appropriate use of serum tumour markers can significantly improve clinical outcome of early detected relapsing patients.

Anselmi Loretta

2006-11-01

120

Cerebrovascular Reserve may be a More Accurate Predictor of Stroke than Degree of ICA or MCA Stenosis.  

Science.gov (United States)

Background It is currently unclear whether the degree of stenosis or the cerebrovascular reserve (CVR) is a better predictor of ischemic stroke. Material and Methods In this study, CVR was measured by perfusion computed tomography with inhalation of 5% CO2 in 37 symptomatic patients with internal carotid artery (ICA) or middle cerebral artery (MCA) stenosis or occlusion. Patients were divided into groups according to the degree of stenosis: ?70% stenosis (stenosis group 1) or <70% stenosis (stenosis group 2); and according to CVR: ?10% CVR (CVR group 1) or <10% CVR (CVR group 2). All patients were given medical treatment. Results During a mean follow-up period of 56.9 months (range 24-73 months), recurrent ipsilateral ischemic stroke occurred in 7 patients. Ischemic stroke occurred in 0 of 19 patients in CVR group 1 (annual risk 0%), 7 of 18 patients in CVR group 2 (annual risk 7.7%), 3 of 18 patients in stenosis group 1 (annual risk 3.3%), and 4 of 19 patients in stenosis group 2 (annual risk 4.7%). Comparisons using Pearson's chi-square test showed a significant difference in the rate of ischemic stroke between CVR group 1 and CVR group 2 (odds ratio 1.700; 95% confidence interval 1.142-2.530; P=0.003), but no significant difference between stenosis group 1 and stenosis group 2 (P=0.691). Conclusions Cerebrovascular reserve may be a more accurate predictor of stroke than degree of ICA or MCA stenosis. PMID:25351338

Liu, Mingyong; Zhou, Lichun

2014-01-01

 
 
 
 
121

MAP Attitude Control System Design and Analysis  

Science.gov (United States)

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The MAP spacecraft will perform its mission in a Lissajous orbit around the Earth-Sun L(sub 2) Lagrange point to suppress potential instrument disturbances. To make a full-sky map of cosmic microwave background fluctuations, a combination fast spin and slow precession motion will be used. MAP requires a propulsion system to reach L(sub 2), to unload system momentum, and to perform stationkeeping maneuvers once at L(sub 2). A minimum hardware, power and thermal safe control mode must also be provided. Sufficient attitude knowledge must be provided to yield instrument pointing to a standard deviation of 1.8 arc-minutes. The short development time and tight budgets require a new way of designing, simulating, and analyzing the Attitude Control System (ACS). This paper presents the design and analysis of the control system to meet these requirements.

Andrews, S. F.; Campbell, C. E.; Ericsson-Jackson, A. J.; Markley, F. L.; ODonnell, J. R., Jr.

1997-01-01

122

IMPROVING SOFTWARE SYSTEMS BY FLOW CONTROL ANALYSIS  

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Full Text Available Using agile methods during the implementation of the system that meets mission critical requirements can be a real challenge. The change in the system built of dozens or even hundreds of specialized devices with embedded software requires the cooperation of a large group of engineers. This article presents a solution that supports parallel work of groups of system analysts and software developers. Deployment of formal rules to the requirements written in natural language enables using formal analysis of artifacts being a bridge between software and system requirements. Formalism and textual form of requirements allowed the automatic generation of message ?ow graph for the (sub system, called the “big-picture-model”. Flow diagram analysis helped to avoid a large number of defects whose repair cost in extreme cases could undermine the legitimacy of agile methods in projects of this scale. Retrospectively, a reduction of technical debt was observed. Continuous analysis of the “big picture model” improves the control of the quality parameters of the software architecture. The article also tries to explain why the commercial platform based on UML modeling language may not be su?cient in projects of this complexity.

Piotr Poznanski

2012-01-01

123

Diagnostic value of perfusion-weighted MRI for evaluating postoperative alteration of cerebral hemodynamics following STA-MCA anastomosis in patients with moyamoya disease  

International Nuclear Information System (INIS)

Surgical revascularization for moyamoya disease prevents cerebral ischemic attacks by improving cerebral blood flow (CBF). But little is known about the changes of CBF and its effect on neurological status during the acute stage after direct bypass for moyamoya disease. Perfusion-weighted magnetic resonance imaging (PWI) by the SE-EPI method was performed 4 and 10 days after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis on 11 sides of 9 patients (male:female=2:7, 24-61 years old) with moyamoya disease. All patients underwent single-photon emission computed tomography (SPECT) 1 and 7 days after surgery. The time-to-peak (TTP) by PWI showed focal decrease at the site of the anastomosis 4 days after STA-MCA anastomosis compared to preoperative TTP, and was further decreased in larger territory 10 days after surgery in all patients. Postoperative cerebral blood volume (CBV) by PWI showed significant increase compared to preoperative CBV in four patients who suffered symptomatic cerebral hyperperfusion after surgery. Postoperative SPECT revealed apparent increase of CBF in all patients and the patency of the STA-MCA bypass was confirmed by MRA. All patients were discharged without neurological deterioration compared to preoperative neurological status, and none of them suffered ischemic attack after surgery. Postoperative decrease in TTP by PWI could be a sensitive parameter for the normalization of CBF after STA-MCA anastomosis in patients with moyamoya disease. Postoperative increase in CBV may suggest cerebral hyperperfusion and could be the optimal predictor for hyperperfusion syndrome after STA-MCA anastomosis in patients with moyamoya disease. (author)

124

Efficacy Assessment of Endovascular Stenting in Patients with Unilateral Middle Cerebral Artery Stenosis Using Statistical Probabilistic Anatomical Mapping Analysis of Basal/Acetazolamide Brain Perfusion SPECT  

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The aim of this study was to evaluate the hemodynamic changes after endovascular stenting in patients with unilateral middle cerebral artery (MCA) stenosis using statistical probabilistic anatomical mapping (SPAM) analysis of basal/acetazolamide (ACZ) Tc-99m ECD brain perfusion SPECT. Eight patients (3 men and 5 women, 64.8{+-}10.5 years) who underwent endovascular stenting for unilateral MCA stenosis were enrolled. Basal/ACZ Tc-99m ECD brain perfusion SPECT studies were performed by one-day protocol before and after stenting. Using SPAM analysis, we compared basal cerebral perfusion (BCP) counts and cerebrovascular reserve (CVR) index of the MCA territory before stenting with those after stenting. After stenting, no patient had any complication nor additional stroke. In SPAM analysis, 7 out of the 8 patients had improved BCP counts of the MCA territory and 7 out of the 8 patients had improved CVR index of the MCA territory after stenting. Before stenting, the mean BCP counts and CVR index in the affected MCA territory were 47.1{+-}2.2 ml/min/100 g and -2.1{+-}2.9%, respectively. After stenting, the mean BCP counts and CVR index in the affected MCA territory were improved significantly (48.3{+-}2.9 ml/min/100 g, p=0.025 and 0.1{+-}1.3%, p=0.036). This study revealed that SPAM analysis of basal/ACZ brain perfusion SPECT would be helpful to evaluate hemodynamic efficacy of endovascular stenting in unilateral MCA stenosis.

Kim, Hae Won; Won, Kyoung Sook; Zeon, Seok Kil; Lee, Chang Young [Keimyung University, School of Medicine, Daegu (Korea, Republic of)

2009-08-15

125

Efficacy Assessment of Endovascular Stenting in Patients with Unilateral Middle Cerebral Artery Stenosis Using Statistical Probabilistic Anatomical Mapping Analysis of Basal/Acetazolamide Brain Perfusion SPECT  

International Nuclear Information System (INIS)

The aim of this study was to evaluate the hemodynamic changes after endovascular stenting in patients with unilateral middle cerebral artery (MCA) stenosis using statistical probabilistic anatomical mapping (SPAM) analysis of basal/acetazolamide (ACZ) Tc-99m ECD brain perfusion SPECT. Eight patients (3 men and 5 women, 64.8±10.5 years) who underwent endovascular stenting for unilateral MCA stenosis were enrolled. Basal/ACZ Tc-99m ECD brain perfusion SPECT studies were performed by one-day protocol before and after stenting. Using SPAM analysis, we compared basal cerebral perfusion (BCP) counts and cerebrovascular reserve (CVR) index of the MCA territory before stenting with those after stenting. After stenting, no patient had any complication nor additional stroke. In SPAM analysis, 7 out of the 8 patients had improved BCP counts of the MCA territory and 7 out of the 8 patients had improved CVR index of the MCA territory after stenting. Before stenting, the mean BCP counts and CVR index in the affected MCA territory were 47.1±2.2 ml/min/100 g and -2.1±2.9%, respectively. After stenting, the mean BCP counts and CVR index in the affected MCA territory were improved significantly (48.3±2.9 ml/min/100 g, p=0.025 and 0.1±1.3%, p=0.036). This study revealed that SPAM analysis of basal/ACZ brain perfusion SPECT would be helpful to evaluate hemodynamic efficacy of endovascular stenting in unilateral MCA stenosis

126

User controlled analysis of gamma ray spectra  

International Nuclear Information System (INIS)

The program 'ANGES' was designed as a general purpose high-resolution ? ray spectrometry program. It offers all main features as commercial software packages except control of acquisition process. The program is able to perform automatic analysis of spectra but it is announced as 'user controlled' because it supplies all intermediate results and gives the opportunity these results to be analyzed and corrected by the user. ANGES offers: multi document Windows interface; detailed visualization of spectra; nuclide library based on another contribution to CRP; energy and FWHM calibrations calculated by means of orthonormal polynomial fitting; peak processing engine based on a non-linear LSQ method for fitting peaks; peak location engine, based on first derivative method is provided to ease the preparation of a spectrum for processing; two methods for efficiency calibration (an efficiency calibration curve and reference table); peak identification and activity calculation procedure; a number of corrections (true coincidence summing, background correction, pile up rejection and so on); an option for processing series of similar spectra. The fitting procedure can be applied to the whole spectrum or to a single Region-of-Interest (ROI). The assumed peak shape is pure Gaussian. All peaks in single ROI are assumed to have the same FWHM. The maximum number of peaks in a single ROI is restricted to 25, the maximum ROI length is 512 channels, and the baseline is described with a polynomial of a degree up to 4. As a result of the identification procedure a report file is issued containing spectrum processing results, list of identified and not identified peaks, list of identified nuclides and background nuclides. (author)

127

Analysis of Controller Communication in En Route Air Traffic Control.  

Science.gov (United States)

To contribute to an understanding of the elements of good air traffic controller communication with the objective of providing recommendations to improve controller communication training, two studies analyzed team communication, ground-air communication, and ground-line communication. The simulated and live traffic analyses examined established…

Seamster, Thomas L.; And Others

128

Some chaotic behaviors in a MCA learning algorithm with a constant learning rate  

International Nuclear Information System (INIS)

Douglas's minor component analysis algorithm with a constant learning rate has both stability and chaotic dynamical behavior under some conditions. The paper explores such dynamical behavior of this algorithm. Certain stability and chaos of this algorithm are derived. Waveform plots, Lyapunov exponents and bifurcation diagrams are presented to illustrate the existence of chaotic behavior

129

Lysozyme induced recovery of the response to cona on mononuclear-cells harvested from mice bearing mca mammary-carcinoma.  

Science.gov (United States)

The effects of lysozyme (hen egg-white lysozyme) on lymphocytes harvested from mice bearing MCa mammary carcinoma were tested at the daily dose of 100 mg/kg given orally for 10 consecutive days. With this experimental paradigm that consists of a significant reduction of lung metastasis formation, lysozyme was seen to be capable of stimulating the recovery of the response to ConA of mononuclear cells, reduced by tumor growth; this effect was particularly evident with splenocytes and GALT lymphocytes. The effects of lysozyme depended: (i) on the presence of plastic adherent cells, (ii) at least in in vitro experiments, on the amount of lysozyme used, being higher at the dose of 250 mug/ml of incubation mixture, and (iii) on the time of challenge with lysozyme. These effects were shown either by measuring the [H-3]-thymidine incorporation into DNA or by application of the sulphorhodamine test for protein synthesis. After in vivo treatment, lysozyme significantly modified the histological architecture of the mucosal immunity of the gut, by causing a significant reduction of the number of the lymphatic nodules placed immediately under the layer of epithelial cells of villi. At the same time no significant modification of Peyer's patches was noted. Together these data stress the role of lysozyme in the modulation of host immunity and, in particular, point out the relevance of the mucosal immunity of the gut as first target for lysozyme activity. PMID:21566996

Pacor, S; Franz, C; Gagliardi, R; Sava, G

1994-04-01

130

Design and Simulation of Seido Buffer for Analog to Digital Converter (ADC) on Multichannel Analyzer (MCA) Application  

International Nuclear Information System (INIS)

Most of our electronic equipment has buffer, thus this make buffer as one of importance in electronic gadget. This paper introduced Single Ended Input Differential Output (SEIDO) buffer to predict the bias at approximately 2.5 V. For this purpose, the input range between -1 mV to 4 V was implemented. The software used to cascade SEIDO buffer is called LTspice IV; an open source software developed by Linear Technology Incorporation. The component involve in this development was Operational Amplifier (OP AMP) AD826 from Analog Devices Incorporation, capacitor and resistor. Kirchhoffs Current Law and Kirchhoffs Voltage Law was applied to calculated voltage gain and biasing voltage. All design has been verified by LTspice IV. The result produced from simulation was between -0.3 V to 6.3 V with bias roughly at 2.5 V. These results prove that it was capable to drive Analog Digital Converter (ADC) that can subsequently apply for Multichannel Analyzer (MCA). (author)

131

Energy transfer from Eu2+ to Mn2+ in M5(PO4)3Cl (M=Ca, Sr)  

International Nuclear Information System (INIS)

M4.95?y(PO4)3Cl:0.05Eu2+, yMn2+ (M=Ca, Sr) phosphors were synthesized at 1200 °C under a reductive atmosphere. The energy transfer mechanism and efficiency (?) from Eu2+ to Mn2+ as well as the quantum efficiency (Q) of the Mn2+ emission were analyzed using PL spectra and decay curves. Least squares fittings of the Eu2+ decay curves indicate that the energy transfer from Eu2+ to Mn2+ follows the exchange mechanism in the Sr system, while besides exchange mechanism other complicated quenching processes are involved in the Ca system. Superficially the ? is high but the Q is low, which implies some energy loss. Two quenching models representative of an “inverse bottleneck process”, which is related to the lifetime mismatch between Eu2+ and Mn2+, and a “charge transfer process“ in the Eu2+–Mn2+ clusters, are proposed. The results may provide some clues for designing excellent sensitizer and activator co-doped phosphors in our further work. -- Highlights: • Energy transfer efficiency of Eu2+ is high and the emission efficiency of Mn2+ is low. • Inverse bottleneck effect related to Eu2+/Mn2+ lifetime mismatch causes quenching. • Charge transfer process in Eu2+–Mn2+ clusters also causes quenching

132

Bounded Linear Stability Margin Analysis of Nonlinear Hybrid Adaptive Control  

Science.gov (United States)

This paper presents a bounded linear stability analysis for a hybrid adaptive control that blends both direct and indirect adaptive control. Stability and convergence of nonlinear adaptive control are analyzed using an approximate linear equivalent system. A stability margin analysis shows that a large adaptive gain can lead to a reduced phase margin. This method can enable metrics-driven adaptive control whereby the adaptive gain is adjusted to meet stability margin requirements.

Nguyen, Nhan T.; Boskovic, Jovan D.

2008-01-01

133

A microprocessor controlled multichannel analyser  

International Nuclear Information System (INIS)

A microprocessor controlled MCA, in which direct memory access techniques are used to allow fast acquisition rates, is presented. The hardware, assembled around an Intel Corp. 8086 central processing unit, is briefly described. Operating commands to the MCA are given through front panel switches and through a keyboard; the command structure and the various software implemented functions are discussed. Among these there are functions for scale selection, comparison and transfer of spectra, marking of areas of interest, arithmetic operations, differentiation and integration of spectra. The corresponding programs and subroutines are described and their source and object codes are made available. (orig.)

134

Experimental study of albumen microspheres modified with stannous chloride-99mTc, MCA intended for the diagnosis of pulmonary diseases  

International Nuclear Information System (INIS)

Functional fitness of 99mTc-MCA (albumin microspheres), a radiopharmaceutical for perfusion scintigraphy of the lungs was studied. The study was carried out with 310 rats and 5 rabbis. Radiometry was performed using Minor Gamma Laboratory device (Gamma, Hungary) and scintigraphy with DSX gamma chamber (Sopha, France). 97% of the agent is accumulated in the lungs as early as 3 min after infusion, and its half-life period in the lungs is 17 h. The agents discharged mainly through the kidneys. Scintigraphic examination of rabbits showed that scintigrams obtained with 99mTc-MCA are not inferior to those obtained with a foreign analog CIS International TCK-5. 8 refs., 1 fig., 2 tabs

135

Power flow analysis for DC voltage droop controlled DC microgrids  

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This paper proposes a new algorithm for power flow analysis in droop controlled DC microgrids. By considering the droop control in the power flow analysis for the DC microgrid, when compared with traditional methods, more accurate analysis results can be obtained. The algorithm verification is carried out by comparing the calculation results with detailed time domain simulation results. With the droop parameters as variables in the power flow analysis, their effects on power sharing and secon...

Li, Chendan; Chaudhary, Sanjay; Dragicevic, Tomislav; Vasquez, Juan Carlos; Guerrero, Josep M.

2014-01-01

136

Techniques of quantitative reliability analysis for control rod drive systems  

International Nuclear Information System (INIS)

Reliability analysis is a method by which the degree of successful performance of a system, under certain stipulated conditions, may be expressed in quantitative terms. Techniques of quantitative reliability analysis for control rod drive systems, which are presented, consist in: drawing up of system block diagrams as basis for the reliability analysis for normal and scram operation; estimation of possible fault rates (''mean rates'') of system components; reliability analysis of the complete control systems (total number of control rod drive mechanisms) on the basis of the analysis of the indjvidual rod drives. (author)

137

Power flow analysis for DC voltage droop controlled DC microgrids  

DEFF Research Database (Denmark)

This paper proposes a new algorithm for power flow analysis in droop controlled DC microgrids. By considering the droop control in the power flow analysis for the DC microgrid, when compared with traditional methods, more accurate analysis results can be obtained. The algorithm verification is carried out by comparing the calculation results with detailed time domain simulation results. With the droop parameters as variables in the power flow analysis, their effects on power sharing and secondary voltage regulation can now be analytically studied, and specialized optimization in the upper level control can also be made accordingly. Case studies on power sharing and secondary voltage regulation are carried out using proposed power flow analysis.

Li, Chendan; Chaudhary, Sanjay

2014-01-01

138

Control design and analysis for underactuated robotic systems  

CERN Document Server

The last two decades have witnessed considerable progress in the study of underactuated robotic systems (URSs). Control Design and Analysis for Underactuated Robotic Systems presents a unified treatment of control design and analysis for a class of URSs, which include systems with multiple-degree-of-freedom and/or with underactuation degree two. It presents novel notions, features, design techniques, and strictly global motion analysis results for these systems. These new materials are shown to be vital in studying the control design and stability analysis of URSs. Control Design and Analysis for Underactuated Robotic Systems includes the modelling, control design, and analysis presented in a systematic way particularly for the following examples: l  directly and remotely driven  Acrobots l  Pendubot l  rotational pendulum l  counter-weighted Acrobot 2-link underactuated robot with flexible elbow joint l  variable-length pendulum l  3-link gymnastic robot with passive first joint l  n-link planar robo...

Xin, Xin

2014-01-01

139

Control and Analysis of Droop and Reverse Droop Controllers for Distributed Generations  

DEFF Research Database (Denmark)

This paper addresses control and analysis of droop and reverse droop control for distributed generations (DG). The droop control is well known applied to the voltage control mode (VCM) DG units, but has limitation when implemented on the current control mode (CCM) units. Therefore, this paper gives a more complete primary control for DG systems that integrates with both VCM and CCM units. The power management can be uniformly achieved by designing proportional droop and reverse droop parameters. And the power sharing effect among CCM and VCM DG units is discussed. Finally, hardware-in-the-loop simulations are carried out to validate the proposed control and analysis.

Wu, Dan; Tang, Fen

2014-01-01

140

Spatial distribution of perfusion abnormality in acute MCA occlusion is associated with likelihood of later recanalization.  

Science.gov (United States)

The aim of this study is to investigate whether different spatial perfusion-deficit patterns, which indicate differing compensatory mechanisms, can be recognized and used to predict recanalization success of intravenous fibrinolytic therapy in acute stroke patients. Twenty-seven acute stroke data sets acquired within 6 hours from symptom onset including diffusion- (DWI) and perfusion-weighted magnetic resonance (MR) imaging (PWI) were analyzed and dichotomized regarding recanalization outcome using time-of-flight follow-up data sets. The DWI data sets were used for calculation of apparent diffusion coefficient (ADC) maps and subsequent infarct core segmentation. A patient-individual three-dimensional (3D) shell model was generated based on the segmentation and used for spatial analysis of the ADC as well as cerebral blood volume (CBV), cerebral blood flow, time to peak (TTP), and mean transit time (MTT) parameters derived from PWI. Skewness, kurtosis, area under the curve, and slope were calculated for each parameter curve and used for classification (recanalized/nonrecanalized) using a LogitBoost Alternating Decision Tree (LAD Tree). The LAD tree optimization revealed that only ADC skewness, CBV kurtosis, and MTT kurtosis are required for best possible prediction of recanalization success with a precision of 85%. Our results suggest that the propensity for macrovascular recanalization after intravenous fibrinolytic therapy depends not only on clot properties but also on distal microvascular bed perfusion. The 3D approach for characterization of perfusion parameters seems promising for further research. PMID:24473482

Siemonsen, Susanne; Forkert, Nils Daniel; Hansen, Anne; Kemmling, Andre; Thomalla, Götz; Fiehler, Jens

2014-05-01

 
 
 
 
141

Roles of Edc3 in the oxidative stress response and CaMCA1-encoded metacaspase expression in Candida albicans.  

Science.gov (United States)

The Edc3 protein is an enhancer of mRNA decapping, and acts as a scaffold protein for the mRNA granules that are known as processing bodies in yeast. In the pathogenic yeast Candida albicans, various stresses, such as glucose depletion, oxidative stress, and filamentation defects, induce the accumulation of processing bodies. Here, we report that the edc3/edc3 deletion strain showed increased resistance to various stresses, including hydrogen peroxide, acetic acid, and high temperature. Oxidative stress is known to induce the intracellular accumulation of reactive oxygen species (ROS) and apoptotic cell death in C. albicans. We found that the ROS level was lower in edc3/edc3 cells than in wild-type cells following oxidative stress. We also observed that expression of the metacaspase gene CaMCA1 was decreased in edc3/edc3 cells. Overexpression of CaMCA1 suppressed the decreased accumulation of ROS and the increased resistance to hydrogen peroxide in edc3/edc3 cells. The catalase Cat1 and the superoxide dismutase Sod1 were upregulated in edc3/edc3 cells as compared with wild-type cells. On the basis of these findings, we suggest that EDC3 plays a critical role in the expression of CaMCA1 and the oxidative stress response in C. albicans. PMID:25158786

Jung, Jong-Hwan; Kim, Jinmi

2014-11-01

142

Set-Up of Digital MCA with HPGE Detector in High Gamma Fields  

International Nuclear Information System (INIS)

The processing time adjustability of a commercial portable spectroscopy workstation based on Digital Signal Processing technology was investigated in areas from highly contaminated (mSv/h dose rate) to high energies (up to 8 MeV) to throughput and resolution performance coaxial Germanium detector. Altering the rise/fall and flat top times of the trapezoidal filter, it was estimated the full width at half maximum at the following peaks: 54Mn 834.8 keV, 60Co 1332.5 keV, 16O(n, p)16N 6129.9 keV, 56Fe(n, ?) 7631.1 keV and 56Fe(n, ?) 7645.5 keV. First type measurement for ultra-high counting and throughput rates was performed at ionex filter which capture activation products (54Mn, 60Co) from primary cooling medium and second type measurement for highest resolution was carried out at pressure water reactor platform during nominal power level giving high energy gamma 6129.9 keV from interaction fast neutrons 16O(n, p)16N and 7631.1 keV, 7645.5 keV from radiation capturing thermal neutrons by 56Fe(n, ?). To measure through energy range up to 8 MeV was reached setting coarse and fine gain to lower range and measuring at contaminated ionex filter by GBq activity was allowed using 50 mm cylindrical collimator by 30 mm diameter, without using this collimator was destroyed whole gamma spectrum despite altering rise/flat times. The results, which are presente times. The results, which are presented, provide optimum performance for high throughput: FWHM 1.71 keV/834.8 keV (54Mn) and 2.00 keV/1332.5 keV (60Co) and best resolution: FWHM 4.49 keV/6129.9 keV (16N), 4.97 keV/7631.1 keV/7645.5 keV (prompt gamma iron) setting 2.8 ?s rise time and 0.6 ?s flat top time. For 0.8/1.2 ?s rise time and 0.2 ?s flat top time occurred results with destroyed resolution broadening and peak shift at 6129.9 keV and 7631.1/7645.5 keV. For rise time above 8.8 ?s and flat time above 0.8 ?s were peaks at 834.8 keV and 1332.5 keV unusable for purpose peak analysis process. (author)

143

Flexible manipulator control experiments and analysis  

Science.gov (United States)

Modeling and control design for flexible manipulators, both from an experimental and analytical viewpoint, are described. From the application perspective, an ongoing effort within the laboratory environment at the Ohio State University, where experimentation on a single link flexible arm is underway is described. Several unique features of this study are described here. First, the manipulator arm is slewed by a direct drive dc motor and has a rigid counterbalance appendage. Current experimentation is from two viewpoints: (1) rigid body slewing and vibration control via actuation with the hub motor, and (2) vibration suppression through the use of structure-mounted proof-mass actuation at the tip. Such an application to manipulator control is of interest particularly in design of space-based telerobotic control systems, but has received little attention to date. From an analytical viewpoint, parameter estimation techniques within the closed-loop for self-tuning adaptive control approaches are discussed. Also introduced is a control approach based on output feedback and frequency weighting to counteract effects of spillover in reduced-order model design. A model of the flexible manipulator based on experimental measurements is evaluated for such estimation and control approaches.

Yurkovich, S.; Ozguner, U.; Tzes, A.; Kotnik, P. T.

1987-01-01

144

Information Theoretical Analysis of Quantum Optimal Control  

Science.gov (United States)

We study the relations between classical information and the feasibility of accurate manipulation of quantum system dynamics. We show that if an efficient classical representation of the dynamics exists, optimal control problems on many-body quantum systems can be solved efficiently with finite precision. In particular, one-dimensional slightly entangled dynamics can be efficiently controlled. We provide a bound for the minimal time necessary to perform the optimal process given the bandwidth of the control pulse, which is the continuous version of the Solovay-Kitaev theorem. Finally, we quantify how noise affects the presented results.

Lloyd, S.; Montangero, S.

2014-07-01

145

Integration of Design and Control Through Model Analysis  

DEFF Research Database (Denmark)

A systematic analysis of the process model is proposed as a pre-solution step for integration of design and control problems. It is shown that the same set of process (control) variables and design (manipulative) variables is employed with different objectives in design and control. Analysis of the phenomena models representing the process model identify the relationships between the important process and design variables, which help to understand, define and address some of the issues related to integration of design and control issues. The model analysis is highlighted through examples involving processes with mass and/or energy recycle. (C) 2000 Elsevier Science Ltd. All rights reserved.

Russel, Boris Mariboe; Henriksen, Jens Peter

2000-01-01

146

Stability analysis of automobile driver steering control  

Science.gov (United States)

In steering an automobile, the driver must basically control the direction of the car's trajectory (heading angle) and the lateral deviation of the car relative to a delineated pathway. A previously published linear control model of driver steering behavior which is analyzed from a stability point of view is considered. A simple approximate expression for a stability parameter, phase margin, is derived in terms of various driver and vehicle control parameters, and boundaries for stability are discussed. A field test study is reviewed that includes the measurement of driver steering control parameters. Phase margins derived for a range of vehicle characteristics are found to be generally consistent with known adaptive properties of the human operator. The implications of these results are discussed in terms of driver adaptive behavior.

Allen, R. W.

1981-01-01

147

Luminescent properties of Eu{sup 3+} in MWO{sub 4} (M=Ca, Sr, Ba) matrix  

Energy Technology Data Exchange (ETDEWEB)

The Eu{sup 3+} doped MWO{sub 4} (M=Ca, Sr, Ba) phosphors were synthesized via high temperature solid state reaction. The crystal phases of these phosphors were identified by X-ray diffraction. Shifts of the peaks in the structure were observed when Ca{sup 2+} sites in the host were completely occupied by the Sr{sup 2+} ions or Ba{sup 2+} ions. As a result of this replacement, the charge-transfer (CT) band exhibited a blue shift from CaWO{sub 4}: Eu{sup 3+} to SrWO{sub 4}: Eu{sup 3+} and BaWO{sub 4}: Eu{sup 3+}. This blue shift could be interpreted with the decreases of the bond covalence between the ligands (L) and the central ion (M) in matrix. In this work, red afterglow originated from the {sup 5}D{sub 0}-{sup 7}F{sub J} (J=0,1,2,3,4) transitions of Eu{sup 3+} could clearly be observed after samples were excited at 254 nm. The thermoluminescence (TL) spectra showed that there were five traps levels in CaWO{sub 4}: Eu{sup 3+} sample and two traps levels in CaWO{sub 4}: Eu{sup 3+} and CaWO{sub 4}: Eu{sup 3+} samples, respectively. The possible explanation of this afterglow phenomenon was also discussed in detail. - Highlights: Black-Right-Pointing-Pointer The red afterglow of Eu{sup 3+} in MWO{sub 4} (M=Sr, Ba) matrix is first observed. Black-Right-Pointing-Pointer The blue shift of the charge-transfer band appears and its proposed explanation is discussed. Black-Right-Pointing-Pointer The feasible mechanism of the afterglow is presented.

Kang, Feng-wen [School of Physics and Optoelectronic Engineering, Guangdong University of Technology, WaiHuan Xi Road, No. 100, Guangzhou 510006 (China); Hu, Yi-hua, E-mail: huyh@gdut.edu.cn [School of Physics and Optoelectronic Engineering, Guangdong University of Technology, WaiHuan Xi Road, No. 100, Guangzhou 510006 (China); Chen, Li; Wang, Xiao-juan; Wu, Hao-yi; Mu, Zhong-fei [School of Physics and Optoelectronic Engineering, Guangdong University of Technology, WaiHuan Xi Road, No. 100, Guangzhou 510006 (China)

2013-03-15

148

A new microcomputer-controlled neutron activation and analysis system  

International Nuclear Information System (INIS)

A microcomputer-controlled irradiation and measurement system and a microprocessor-controlled sample changer have been installed at the SLOWPOKE-2 Facility at the Royal Military College of Canada (RMC). These systems can provide the gamut of instrumental neutron activation analysis (INAA) techniques for the analyst. Custom software has been created for system control, data acquisition, and off-line spectral analysis using programs that incorporate Gaussian peak-fitting methods of analysis. The design and use of the equipment is discussed, and the performance is illustrated with results obtained from the analysis of marine sediment and biological reference materials

149

Use of 123I-IMP brain SPET to predict outcome following STA-MCA bypass surgery: cerebral blood flow but not vasoreactivity is a predictive parameter  

International Nuclear Information System (INIS)

Superficial temporal artery - middle cerebral artery (STA-MCA) bypass surgery might improve the cerebral blood flow (CBF) but fail to reduce the risk of post-surgical events such as ischaemic stroke. In this study, we studied retrospectively whether the risk of post-surgical events corresponded to the change in resting CBF and/or the change in vasoreactivity observed before and after STA-MCA surgery using N-isopropyl-I-123-p-iodoamphetamine (123I-IMP) brain single-photon emission tomography (SPET). 123I-IMP brain SPET images obtained at rest and following acetazolamide challenge both before and after STA-MCA surgery were studied in 30 patients. Resting CBF was estimated semiquantitatively using the resting count ratios of the middle cerebral artery (MCA) area to the cerebellum. Acetazolamide challenge was assumed to result in an average increase in flow of 40% in the cerebellum. The vasoreactive response was then estimated as the ratio of the change in counts (acetazolamide - rest) to the resting cerebellar counts multiplied by 1.4. We classified 14 patients (50.5±19.3 years) into group I, who had a change in their resting CBF from before to after surgery of >10%, and 16 patients (54.0±18.8 years) into group II, who had a change in their resting CBF from before to after surgery of ?10%. Oxygen-15 positron emission tomography (PET) studies were performed in five patients from group I and five patients from group II. One post-surgical event occurred in group I while there were eight post-surgical events in group II (P<0.05). Resting CBF improved by 20.4%±7.5% in group I and by 0.9%±6.9% in group II patients after surgery (P<0.001). No significant difference in the improvement in vasoreactivity was observed between group I patients (32.6%±17.7%) and group II patients (24.6%±15.6%) following surgery. Patients in the group I PET subset showed normalization of oxygen extraction fraction (OEF) from 0.59±0.09 before surgery to 0.46±0.06 after surgery (P<0.05), while patients in the group II PET subset showed no statistical difference in OEF before surgery (0.58±0.14) and after surgery (0.54± 0.05). We conclude that the outcome of STA-MCA bypass surgery can be predicted by the improvement in resting CBF but not by the improvement in vasoreactivity. (orig.)

150

Post-Operative Follow-up of Breast Cancer Patients Using Serum Tumor Markers: CEA and CA15.3 vs MCA in the Early Detection of Distant Metastases  

Directory of Open Access Journals (Sweden)

Full Text Available In breast cancer current guidelines do not recommended the routine use of serum tumor markers. Differently, we observed that CEA, CA 15.3 panel permits early detection for most relapsing patients. As high sensitivity and specificity and different cut-off values have been reported for Mucin-like Carcinoma associated Antigen (MCA, we compared MCA with the above mentioned tumor markers. In 150 breast cancer patients submitted to post-operative follow-up with tumor markers, we compared MCA (cut-off values, = 11 and = 15 U mL -1 with CEA and CA15.3 for detection of relapse. Distant metastases occurred in 12 (8% of the 150 patients who were disease-free at the beginning of the study. MCA sensitivity with both cut-off values was higher than that of CEA or CA15.3 (65 vs 12%, 33% and (55 vs 17%, 31% , respectively. With cut-off = 11 U mL -1, MCA showed the lowest specificity (32%. With out-off =15 U mL -1, MCA specificity was lower than that of CEA and CA 15.3 (71 vs 95 and 96%, respectively. At both the evaluated cut-off values serum MCA sensitivity is higher than that of CEA or CA15.3 but its specificity is lower than them. These findings further support the need for prospective randomized clinical trial to assess whether post-operative follow-up with an appropriate use of serum tumor markers such as MCA can significantly improve clinical outcome of early detected relapsing patients.

2008-01-01

151

Nonlinear Robustness Analysis Tools for Flight Control Law Validation & Verification  

Science.gov (United States)

Loss of control in flight is among the highest aviation accident categories for both the number of accidents and the number of fatalities. The flight controls community is seeking an improved validation tools for safety critical flight control systems. Current validation tools rely heavily on linear analysis, which ignore the inherent nonlinear nature of the aircraft dynamics and flight control system. Specifically, current practices in validating the flight control system involve gridding the flight envelope and checking various criteria based on linear analysis to ensure safety of the flight control system. The analysis and certification methods currently applied assume the aircrafts' dynamics is linear. In reality, the behavior of the aircraft is always nonlinear due to its aerodynamic characteristics and physical limitations imposed by the actuators. This thesis develops nonlinear analysis tools capable of certifying flight control laws for nonlinear aircraft dynamics. The proposed analysis tools can handle both the aerodynamic nonlinearities and the physical limitations imposed by the actuators in the aircrafts' dynamics. This proposed validation technique will extend and enrich the predictive capability of existing flight control law validation methods to analyze nonlinearities. The objective of this thesis is to provide the flight control community with an advanced set of analysis tools to reduce aviation fatalities and accidents rate.

Chakraborty, Abhijit

152

INTERNAL AUDIT COMPARATIVE ANALYSIS - MANAGEMENT CONTROL CONCEPTS  

Directory of Open Access Journals (Sweden)

Full Text Available Given Romania's integration into the European Union we consider it appropriate to clarify some terms used in auditing activities of both public funds and European funds. International practice requires a clear separation of internal audit activities from other management control concepts and recommend to establish an internal controlling system as well as an internal audit structure under the coordination of the manager as being the only ways cap able to respond to current risks faced by public entities. Internal Audit, along its evolution - characterized by complex dynamics and adaptability - created confusion regarding the concept of control. The research presented in this paper is based on works published to date regarding the conceptual boundaries of this notion.

MIHAI-DOREL JURCHESCU

2010-01-01

153

Risk Analysis of Safety-Critical Control Systems  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with problems associated with risks analysis of a safety-critical control system. In the paper there are introduced recommendations enabling practical enforceability of risk analysis by the assurance of sufficient objectivity level. In the initial phases of the system lifecycle risk analysis serves for a tolerable hazard rate definition for individual safety relevant functions. In the end of the control system development process the risk analysis (an analysis of failures consequences on system safety serves for the verification of system safety attributes.

Karol Rastocny

2008-01-01

154

Space Station Environment Control and Life Support System Pressure Control Pump Assembly Modeling and Analysis  

Science.gov (United States)

This paper presents the Modeling and Analysis of the Space Station Environment Control and Life Support System Pressure Control Pump Assembly (PCPA). The contents include: 1) Integrated PCPA/Manifold Analyses; 2) Manifold Performance Analysis; 3) PCPA Motor Heat Leak Study; and 4) Future Plans. This paper is presented in viewgraph form.

Schunk, R. Gregory

2002-01-01

155

Integration of Design and Control through Model Analysis  

DEFF Research Database (Denmark)

A systematic computer aided analysis of the process model is proposed as a pre-solution step for integration of design and control problems. The process model equations are classified in terms of balance equations, constitutive equations and conditional equations. Analysis of the phenomena models representing the constitutive equations identify the relationships between the important process and design variables, which help to understand, define and address some of the issues related to integration of design and control. Furthermore, the analysis is able to identify a set of process (control) variables and design (manipulative) variables that may be employed with different objectives in design and control for the integrated problem. The computer aided model analysis is highlighted through illustrative examples, involving processes with mass and/or energy recycle, where the important design and control (structure selection) issues for the integrated problems are considered. (C) 2002 Elsevier Science Ltd. All rights reserved.

Russel, Boris Mariboe; Henriksen, Jens Peter

2002-01-01

156

Information Control Analysis of Business Group  

Directory of Open Access Journals (Sweden)

Full Text Available The implementation of modern enterprise strategy needs the support of information system and networked information technology. This study confirms the importance of business group information construction by the analysis of information technology dynamics and the result of information technology development effected industry. Besides, it discussed the common features of Executive Information Systems (EIS and the balanced scorecard application in the exploitation of Executive Information Systems. What’s more, this study probe further into the demand and analysis tools of business group information system and put forward the key issues to structure the group integrated information system.

Wang Wen-Sheng

2013-01-01

157

Analysis of pressurizer pressure control system using MAAP5 code  

International Nuclear Information System (INIS)

Full text of publication follows. MAAP4 code is a severe accident analysis code, widely used in nuclear industry. Pressurizer response plays an important role in transient and accident analysis. However, only simplified pressurizer pressure control system model is included in MAAP4 code. The purpose of the paper is to modify the pressurizer pressure control system model in MAAP4 without compiling the code, promoting the simulation capability and accuracy of the MAAP4 code. The typical proportional and integral (PI) controller model is successfully coupled with current code without compiling. Typical control system analysis is analyzed using MAAP4. Furthermore, the characteristic of PI controller is demonstrated, which reduces the steady state error to zero. With the revised pressurizer pressure control system, the transient responses are more realistic. It can be coupled with balance of plant model for whole plant simulation in MAAP5 code in the near future. (authors)

158

Analysis and control of interleaved Swiss rectifiers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Development of fast charging stations is expected to reduce the charging time required by Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs). Fast charging stations require the rectification of the grid AC voltage to a DC voltage while maintaining high power factor (PF) and low total harmonic distortion (THD) on the grid side. Furthermore, the chargers must be able to provide a controllable DC output voltage to meet the voltage level requirement of the battery pack. This res...

Ahmed, Munadir A.

2013-01-01

159

Process control oriented quench analysis of a SSC magnet  

International Nuclear Information System (INIS)

Control of the refrigeration system for the SSC magnets will require a very advanced process control system. To be effective, the control system must be able to recognize magnet quench behavior and respond to mitigate the event and recover stable operating conditions. The purpose of this quench analysis is to provide quench characteristics in the format of manifold pressure and temperature rise with time as well as to evaluate the outflow that must be accommodated by the refrigeration system. The method of analysis and results of the analysis are described. 4 refs., 11 figs., 2 tabs

160

The Importance of Variance Analysis for Costs Control in Organizations  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This review aimed at examining the importance of variance analysis for cost control in organizations. The study x-rayed the concept of variance analysis, types, sources, objectives and its significance. The study reported that variance analysis has significant influence in evaluating individual performance in organizations, assignment of responsibilities to individuals and assisting management to rely on the principle of management by exception and recommended among others, variances analysis...

Okoh, L. O.; Uzoka, P.

2012-01-01

 
 
 
 
161

A high performance multichannel analyzer with self contained isotope analysis capability  

International Nuclear Information System (INIS)

This paper describes a multichannel analyzer system which has been developed around a popular 16-bit microprocessor family with an embedded firmware operating system. The CPU with its ability to address a megabyte of memory opens the door to a sophisticated level of analysis never before available in a stand alone MCA. This level of analysis capability coupled with a unique man-machine interface set a new standard for MCA operation

162

Effective Methods Analysis for Machines Noise Control  

Directory of Open Access Journals (Sweden)

Full Text Available Damping of mechanical vibrations of thin-walled elements is simultaneously associated with suppression of vibrations in the source and on their spreading ways of air or structural noise. Nevertheless, the real source of vibrations is the activator of plate vibrations. The absorption of structures thin-walled elements vibrations (air pipes, thin metal disks can be done by classical method by connecting the vibrating surface of mass with springy-viscous elements. In other cases various methods of noise control and damping materials are applicable.

Mohammed A. Alnawafleh

2004-01-01

163

Comparative Performance Analysis between Fuzzy Logic Controller (FLC and PID Controller for an Inverted Pendulum System  

Directory of Open Access Journals (Sweden)

Full Text Available The idea of this paper is to compare the time-response performance characteristics between two controllers having different strategy for an inverted pendulum system. The main objective is to determine which control strategy brings the better results in comparative analysis with regard to pendulum’s angle and cart’s position of the system. The inverted pendulum system in fact a critical and challenging control problem, which continually moves away from a stable state. Two Control strategies for an Inverted pendulum system model are presented for stabilized controlling such as Proportional-Integral-Derivatives (PID and Fuzzy Logic Controller (FLC Controllers. Matlab Simulation has been performed on Simulink platform shows that both controllers successfully controls Multi-output Inverted pendulum system. However PID is more efficient and has a better time response characteristics than FLC control strategy.

Aleem Ahmed Khan

2012-10-01

164

Modeling and Analysis of PI Controller Based Speed Control of Brushless DC Motor Drive.  

Directory of Open Access Journals (Sweden)

Full Text Available The Brushless DC motors (BLDC find widespread applications in domestic and industries due to their low and high power density and ease of speed control. To accomplish desired level of performance the motor requires suitable speed controllers. In case of permanent magnet Brushless DC motors, usually control of speed is reached by using proportional integral (PI controller. Although the conventional PI controllers are widely used in the industry due to their simple control structure and ease of implementation, these controllers pose difficulties where there are some control complexity such as nonlinearity, load disturbances and parametric variations. Moreover PI controllers require precise linear mathematical models. In this paper, the analysis and mathematical modeling of BLDC motor is implemented. Also, speed control of three phase BLDC motor drive using power electronic device is projected by using matlab/Simulink. The simulation result shows the improved performance of developed Brushless DC motor drive.

Mr.P.Nagasekhar Reddy

2013-09-01

165

Comparative Performance Analysis between Fuzzy Logic Controller (FLC) and PID Controller for an Inverted Pendulum System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The idea of this paper is to compare the time-response performance characteristics between two controllers having different strategy for an inverted pendulum system. The main objective is to determine which control strategy brings the better results in comparative analysis with regard to pendulum’s angle and cart’s position of the system. The inverted pendulum system in fact a critical and challenging control problem, which continually moves away from a stable state. Two Control strategie...

Aleem Ahmed Khan; Kashan Hussain

2012-01-01

166

Proposed design for a high quality PC-MCA add on card with reduced electronic hardware [Paper No.: I4  

International Nuclear Information System (INIS)

This paper describes the design and construction of an 8 k personal computer analyser (PCA), used for nuclear pulse height analysis. The complete PCA uses a single card that can be mounted in a slot of personal computer. The PCA circuit consists of an interface memory circuit and an 8-K nuclear ADC along with its associated controls giving differential non-linearity (DNL) of ? ± 1% with conversion time of nearly 15 micro sec. All standard facilities like selection of conversion gain, digital offset etc. are provided. (author). 3 refs., 2 figs

167

Flexible Space Station Attitude Control System analysis and design  

Science.gov (United States)

The Space Station Freedom (SSF) Attitude Control System (ACS) is designed to ensure integrated dynamic stability and performance under coupling of attached flexible bodies, articulation of payloads, interaction of substructural joint control systems with the primary structure, and docking transients. In particular, the objective of the flex control system design is to provide adequate flex stability margin and to minimize control effector induced flex oscillations. This paper describes a flexible body control methodology and present analysis results. Low bandwidth Control Moment Gyroscopes and Momentum Management (CMG/MM) attitude control system and Reaction Control System (RCS) rigid body controllers provide wide separation between rigid body control bandwidth and the first significant flex mode. This gives rise to a feasible design approach which uses gain stabilization. The design provides 18 dB gain margin for all flex modes with nominal flex parameters. The modal parameter uncertainty analysis results indicate that 18 dB margin is sufficient. No active damping of flex modes is provided. The design approach and integrated analysis tools are also discussed.

Chang, David S.; Lee, John F. L.

1992-08-01

168

Discrete Mechanics and Optimal Control: an Analysis  

CERN Document Server

The optimal control of a mechanical system is of crucial importance in many realms. Typical examples are the determination of a time-minimal path in vehicle dynamics, a minimal energy trajectory in space mission design, or optimal motion sequences in robotics and biomechanics. In most cases, some sort of discretization of the original, infinite-dimensional optimization problem has to be performed in order to make the problem amenable to computations. The approach proposed in this paper is to directly discretize the variational description of the system's motion. The resulting optimization algorithm lets the discrete solution directly inherit characteristic structural properties from the continuous one like symmetries and integrals of the motion. We show that the DMOC approach is equivalent to a finite difference discretization of Hamilton's equations by a symplectic partitioned Runge-Kutta scheme and employ this fact in order to give a proof of convergence. The numerical performance of DMOC and its relationsh...

Ober-Bloebaum, S; Marsden, J E

2008-01-01

169

COMQC, Quality Control Statistical Analysis for Means, Errors, Skewness, Kurtosis  

International Nuclear Information System (INIS)

1 - Description of problem or function: COMQC is a quality control data analysis statistical program that calculates mean, standard deviation, range, skewness and kurtosis. Tolerance limits, confidence limits on the percent defective, and a one-way analysis of variance are also provided. 2 - Method of solution: The program consists of four subroutines which produce the following: histograms, control charts, group comparisons, and process capability study. Standard statistical methods and techniques are employed

170

Analysis and Design of PLL Motor Speed Control System  

Directory of Open Access Journals (Sweden)

Full Text Available Phase-locked technology in motor speed control system has a wide range of applications, Especially for high accuracy in the motor steady speed operation situation, more and more use of phase-locked servo control system. This paper describes the block diagram and mathematical model of phase-locked control system, Shows the circuit parameter calculation method This and combined with design example analysis of phase-locked control system, Indicated through the theory and practice, using PLL can obtain good speed control precision.

Qi Chao Zhang

2013-10-01

171

Aircraft Accident Prevention: Loss-of-Control Analysis  

Science.gov (United States)

The majority of fatal aircraft accidents are associated with loss-of-control . Yet the notion of loss-of-control is not well-defined in terms suitable for rigorous control systems analysis. Loss-of-control is generally associated with flight outside of the normal flight envelope, with nonlinear influences, and with an inability of the pilot to control the aircraft. The two primary sources of nonlinearity are the intrinsic nonlinear dynamics of the aircraft and the state and control constraints within which the aircraft must operate. In this paper we examine how these nonlinearities affect the ability to control the aircraft and how they may contribute to loss-of-control. Examples are provided using NASA s Generic Transport Model.

Kwatny, Harry G.; Dongmo, Jean-Etienne T.; Chang, Bor-Chin; Bajpai, Guarav; Yasar, Murat; Belcastro, Christine M.

2009-01-01

172

Effect of the A-site cation on methane oxidation of perovskite-type (La1?xMx)CoO3 (M=Ca, Sr, and Ba)  

International Nuclear Information System (INIS)

Perovskite-type (La1?xMx)CoO3 (M=Ca, Sr, and Ba) synthesized at 700 °C in air using the polymerizable complex method had a rhombohedral perovskite-type structure in the range of x?0.06. The oxygen content of the samples was 2.98–2.99, and the specific surface area was 3.5–8.3 m2/g regardless of the M ion or x. The Rietveld method indicated that the Co–O distance was also constant regardless of the M ion or x, and that the Co–O–Co angle between two CoO6 octahedra increased with an increase in the ionic radius of the M ion. The temperature corresponding to the 50% conversion (T1/2) of CH4 oxidation was almost constant for the samples with x=0.04, while the T1/2 of the samples with x=0.06 was linearly lowered with increases in the ionic radius of the M ion. - Graphical abstract: The conversion from CH4 to CO2 and H2O on (La0.94M0.06)CoO3 (M=Ca, Sr, and Ba). Highlights: ? (La1?xMx)CoO3 (M=Ca, Sr, and Ba) was synthesized using the polymerizable complex method. ? The Co–O distance was constant regardless of the M ion or x. ? The Co–O–Co angle increased with an increase in the ionic radius of the M ion. ? CH4 oxidation started above 300 °C and finished at 700 °C. ? The catalytic activity increased with increases in the ionic radius of the M ion.M ion.

173

Effects of chemical carcinogens on hemopoiesis, immunopoiesis and viral oncogenesis. Three year technical progress report, February 1, 1977-September 30, 1979. [MMS; BP; DMBA; propane sultone; MCA; mice  

Energy Technology Data Exchange (ETDEWEB)

Studies were initiated to evaluate in an in vitro system selected chemical carcinogens derived from energy producing hydrocarbons for their effect on the hematopoietic and immune systems. Studies were also conducted to determine whether the selected carcinogens could interact with leukemogenic virus to produce leukemia in mice. Five compounds have been investigated thus far: (1) methylmethane sulfonate (MMS); (2) benzo(a)pyrene (BP); (3) 7,12 dimethylbenz(a)anthracene (DMBA); (4) propane sultone (PS); and (5) 20-methylcholanthrene (MCA). MMS inhibited both the colony forming ability of CFU-S and the immune response of PFC. MMS also potentiated the development of Friend viral leukemia when given to mice before the virus. The observed potentiation did not appear to correlate with the suppressed antibody formation response of the PFC. Good temporal correlation was found between leukemia potentiation and suppression of the colony forming ability of the CFU-S. DNA synthetic activity was also increased without a substantial increase in the number of CFU-S over that found for normal mice. BP also inhibited colony forming by the CFU-S. Effects of BP on PFC response were of a mixed nature, varying as a function of time. When given in conjunction with Friend leukemia virus, a potentiation of leukemia development was observed. To date no suppressive effect of DMBA on PFC response has been observed. The results on potentiation of viral leukemogenesis are also varied. With a high virus dose, DMBA inhibited leukemia development. However, when a subthreshold dose of virus was employed, injections of DMBA resulted in potentiation. Studies with MCA and PS were only recently begun. The effects of PS on PFC response were measured at selected dates. Suppression was found only at one time. Initial data suggests that MCA may potentiate the development of viral leukemogenesis when given before the virus. (ERB)

OKunewick, J.P.; Raikow, R.B.; Meredith, R.F.

1979-09-01

174

Comparative analysis of control circuits for charge-coupled devices  

International Nuclear Information System (INIS)

Different variants of plotting control circuits of charge-coupled devices (CCD) are considered. The problem of control over a numerous class of devices on CCD is connected with formation of multiphase pulse consequences on bars with large capacities as well as regulation of the control signal level. The results of comparative analysis of quick response and economy of the control circuits assembled on the following elements-MDS-transistors CMOS devices and bipolar transistors are presented. The analysis has shown that control circuits on MDS-transistors are most uneconomical though their technology is compatible with the technology of CCD construction and they permit to construct finished complex devices on one crystal. Circuits on CMOS- transistors are most economical. But when it is necessary to use powerful (on amper orders currents) transistors the application of bipolar transistors (BT) can be more effective. High speed of response of the control circuits on mutually adding BT should be also marked

175

Controller design based on ? analysis and PSO algorithm.  

Science.gov (United States)

In this paper an evolutionary algorithm is employed to address the controller design problem based on ? analysis. Conventional solutions to ? synthesis problem such as D-K iteration method often lead to high order, impractical controllers. In the proposed approach, a constrained optimization problem based on ? analysis is defined and then an evolutionary approach is employed to solve the optimization problem. The goal is to achieve a more practical controller with lower order. A benchmark system named two-tank system is considered to evaluate performance of the proposed approach. Simulation results show that the proposed controller performs more effective than high order H(?) controller and has close responses to the high order D-K iteration controller as the common solution to ? synthesis problem. PMID:24314832

Lari, Ali; Khosravi, Alireza; Rajabi, Farshad

2014-03-01

176

OPTIMAL DESIGN AND ANALYSIS OF A CHEMICAL PROCESS CONTROL SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available The present work describes the design and analysis of a chemical process control system. The design is accomplished to attain the optimality of control operation. The total system is supposed to consist of the suitable controller operated in the closed loop manner with negative feedback path, affording the suitable output to the input. The optimality of the performance for the system is considered to be attained with gain of the (PD controller [1], so chosen that the integral square error becomes a minimum. The overall system is found to be stable, controllable, and observable. The system is also analyzed in sampled data control domain (z domain. The stability in z domain is analyzed using Jury’s Stability test. MATLAB software is appropriately used in the entire analysis.

Ashis Kumar Das

2013-03-01

177

Advanced stability analysis for laminar flow control  

Science.gov (United States)

Five classes of problems are addressed: (1) the extension of the SALLY stability analysis code to the full eighth order compressible stability equations for three dimensional boundary layer; (2) a comparison of methods for prediction of transition using SALLY for incompressible flows; (3) a study of instability and transition in rotating disk flows in which the effects of Coriolis forces and streamline curvature are included; (4) a new linear three dimensional instability mechanism that predicts Reynolds numbers for transition to turbulence in planar shear flows in good agreement with experiment; and (5) a study of the stability of finite amplitude disturbances in axisymmetric pipe flow showing the stability of this flow to all nonlinear axisymmetric disturbances.

Orszag, S. A.

1981-02-01

178

Updated Meta-Analysis of Learner Control within Educational Technology  

Science.gov (United States)

Giving a student control over their learning has theoretical and intuitive appeal, but its effects are neither powerful nor consistent in the empirical literature base. This meta-analysis updated previous meta-analytic research by Niemiec, Sikorski, and Walberg by studying the overall effectiveness of providing learner control within educational…

Karich, Abbey C.; Burns, Matthew K.; Maki, Kathrin E.

2014-01-01

179

Isotopic analysis of plutonium by computer controlled mass spectrometry  

International Nuclear Information System (INIS)

Isotopic analysis of plutonium chemically purified by ion exchange is achieved using a thermal ionization mass spectrometer. Data acquisition from and control of the instrument is done automatically with a dedicated system computer in real time with subsequent automatic data reduction and reporting. Separation of isotopes is achieved by varying the ion accelerating high voltage with accurate computer control

180

Cognitive Task Analysis of Prioritization in Air Traffic Control.  

Science.gov (United States)

A cognitive task analysis was performed to analyze the key cognitive components of the en route air traffic controllers' jobs. The goals were to ascertain expert mental models and decision-making strategies and to identify important differences in controller knowledge, skills, and mental models as a function of expertise. Four groups of…

Redding, Richard E.; And Others

 
 
 
 
181

A performance requirements analysis of the SSC control system  

International Nuclear Information System (INIS)

This paper presents the results of analysis of the performance requirements of the Superconducting Super Collider Control System. We quantify the performance requirements of the system in terms of response time, throughput and reliability. We then examine the effect of distance and traffic patterns on control system performance and examine how these factors influence the implementation of the control network architecture and compare the proposed system against those criteria. (author)

182

Manual-control Analysis Applied to the Money-supply Control Task  

Science.gov (United States)

The recent procedure implemented by the Federal Reserve Board to control the money supply is formulated in the form of a tracking model as used in the study of manual-control tasks. Using this model, an analysis is made to determine the effect of monetary control on the fluctuations in economic output. The results indicate that monetary control can reduce the amplitude of fluctuations at frequencies near the region of historic business cycles. However, with significant time lags in the control loop, monetary control tends to increase the amplitude of the fluctuations at the higher frequencies. How the investigator or student can use the tools developed in the field of manual-control analysis to study the nature of economic fluctuations and to examine different strategies for stabilization is examined.

Wingrove, R. C.

1984-01-01

183

Data Analysis and Decision Trees for Analysis and B2C Controls  

Directory of Open Access Journals (Sweden)

Full Text Available This study uses a two-step procedure for the evaluation of B2C controls, first, using a Data Envelopment Analysis (DEA model, second, decision trees. The results of the DEA model indicate that retail firms and information service providers implement B2C controls more effectively than financial firms do. Controls for system continuity are implemented more effectively than entry controls. In financial firms, controls for system continuity, communication controls and entry controls, in a dropping order, are effectively followed in B2C approaches. Every company can determine its relative level of reduction in each part of controls in order to make the control system effective. The firms that effectively implement B2C controls are determined using a decision tree model. The decision tree model issued to suggest the level of controls and argued rules for controls guidance. This state the possibility of using decision trees for controls evaluation in B2C approaches.

Mohammad Nazaripour

2012-09-01

184

Contamination control - the analysis of things as they should be  

International Nuclear Information System (INIS)

Contamination can be controlled in chemical analyses by the use of suitable containers, cleanliness, appropriate apparatus design, isolation of the analysis process from air, and in-situ analysis. Examples based on analyses of organic reactor coolant, metals, and underground natural waters are given. (LL)

185

Supercritical carbon dioxide cycle control analysis.  

Energy Technology Data Exchange (ETDEWEB)

This report documents work carried out during FY 2008 on further investigation of control strategies for supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle energy converters. The main focus of the present work has been on investigation of the S-CO{sub 2} cycle control and behavior under conditions not covered by previous work. An important scenario which has not been previously calculated involves cycle operation for a Sodium-Cooled Fast Reactor (SFR) following a reactor scram event and the transition to the primary coolant natural circulation and decay heat removal. The Argonne National Laboratory (ANL) Plant Dynamics Code has been applied to investigate the dynamic behavior of the 96 MWe (250 MWt) Advanced Burner Test Reactor (ABTR) S-CO{sub 2} Brayton cycle following scram. The timescale for the primary sodium flowrate to coast down and the transition to natural circulation to occur was calculated with the SAS4A/SASSYS-1 computer code and found to be about 400 seconds. It is assumed that after this time, decay heat is removed by the normal ABTR shutdown heat removal system incorporating a dedicated shutdown heat removal S-CO{sub 2} pump and cooler. The ANL Plant Dynamics Code configured for the Small Secure Transportable Autonomous Reactor (SSTAR) Lead-Cooled Fast Reactor (LFR) was utilized to model the S-CO{sub 2} Brayton cycle with a decaying liquid metal coolant flow to the Pb-to-CO{sub 2} heat exchangers and temperatures reflecting the decaying core power and heat removal by the cycle. The results obtained in this manner are approximate but indicative of the cycle transient performance. The ANL Plant Dynamics Code calculations show that the S-CO{sub 2} cycle can operate for about 400 seconds following the reactor scram driven by the thermal energy stored in the reactor structures and coolant such that heat removal from the reactor exceeds the decay heat generation. Based on the results, requirements for the shutdown heat removal system may be defined. In particular, the peak heat removal capacity of the shutdown heat removal loop may be specified to be 1.1 % of the nominal reactor power. An investigation of the oscillating cycle behavior calculated by the ANL Plant Dynamics Code under specific conditions has been carried out. It has been found that the calculation of unstable operation of the cycle during power reduction to 0 % may be attributed to the modeling of main compressor operation. The most probable reason for such instabilities is the limit of applicability of the currently used one-dimensional compressor performance subroutines which are based on empirical loss coefficients. A development of more detailed compressor design and performance models is required and is recommended for future work in order to better investigate and possibly eliminate the calculated instabilities. Also, as part of such model development, more reliable surge criteria should be developed for compressor operation close to the critical point. It is expected that more detailed compressor models will be developed as a part of validation of the Plant Dynamics Code through model comparison with the experiment data generated in the small S-CO{sub 2} loops being constructed at Barber-Nichols Inc. and Sandia National Laboratories (SNL). Although such a comparison activity had been planned to be initiated in FY 2008, data from the SNL compression loop currently in operation at Barber Nichols Inc. has not yet become available by the due date of this report. To enable the transient S-CO{sub 2} cycle investigations to be carried out, the ANL Plant Dynamics Code for the S-CO{sub 2} Brayton cycle was further developed and improved. The improvements include further optimization and tuning of the control mechanisms as well as an adaptation of the code for reactor systems other than the Lead-Cooled Fast Reactor (LFR). Since the focus of the ANL work on S-CO{sub 2} cycle development for the majority of the current year has been on the applicability of the cycle to SFRs, work has started on modification of the ANL Plant Dynamics Code to allow

Moisseytsev, A.; Sienicki, J. J. (Nuclear Engineering Division)

2011-04-11

186

LOFT PSMG Speed Control System frequency response analysis  

International Nuclear Information System (INIS)

An analysis was done to gain insight into the shape of the open loop frequency response of the PSMG Speed Control System. The results of the analysis were used as a guide to groom the proportional band and reset time settings of the 2 mode controller in the speed control system. The analysis shows that when an actuator with a timing of 90 degrees per 60 seconds is installed in the system the proportional band and reset time should be 316% and 1 minute. Whereas when grooming the system a proportional band and reset time of 150% and 1.5 minutes were found to be appropriate. The closeness of the settings show that even though a linear model was used to describe the non-linear PSMG Speed Control System, it was accurate enough to be used as a guide to groom the proportional band and reset time settings

187

Analysis of control rod behavior based on numerical simulation  

International Nuclear Information System (INIS)

The main function of a control rod is to control core reactivity change during operation associated with changes in power, coolant temperature, and dissolved boron concentration by the insertion and withdrawal of control rods from the fuel assemblies. In a scram, the control rod assemblies are released from the CRDMs (Control Rod Drive Mechanisms) and, due to gravity, drop rapidly into the fuel assemblies. The control rod insertion time during a scram must be within the time limits established by the overall core safety analysis. To assure the control rod operational functions, the guide thimbles shall not obstruct the insertion and withdrawal of the control rods or cause any damage to the fuel assembly. When fuel assembly bow occurs, it can affect both the operating performance and the core safety. In this study, the drag forces of the control rod are estimated by a numerical simulation to evaluate the guide tube bow effect on control rod withdrawal. The contact condition effects are also considered. A full scale 3D model is developed for the evaluation, and ANSYS - commercial numerical analysis code - is used for this numerical simulation. (authors)

188

10 CFR 74.43 - Internal controls, inventory, and records.  

Science.gov (United States)

...MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR...controls. (1) A management structure shall...material control and accounting (MC&A) functions...that assess the performance of the system...and document management's action on prior...include a review and evaluation of any...

2010-01-01

189

Nonlinear analysis and control of a continuous fermentation process  

DEFF Research Database (Denmark)

Different types of nonlinear controllers are designed and compared for a simple continuous bioreactor operating near optimal productivity. This operating point is located close to a fold bifurcation point. Nonlinear analysis of stability, controllability and zero dynamics is used to investigate open-loop system properties, to explore the possible control difficulties and to select the system output to be used in the control structure. A wide range of controllers are tested including pole placement and LQ controllers, feedback and input–output linearization controllers and a nonlinear controller based on direct passivation. The comparison is based on time-domain performance and on investigating the stability region, robustness and tuning possibilities of the controllers. Controllers using partial state feedback of the substrate concentration and not directly depending on the reaction rate are recommended for the simple fermenter. Passivity based controllers have been found to be globally stable, not very sensitive to the uncertainties in the reaction rate and controller parameter but they require full nonlinear state feedback.

Kristensen, Niels Rode; JØrgensen, Sten Bay

2002-01-01

190

Genetic diversity analysis in rice mutants using isozyme and Morphological markers  

International Nuclear Information System (INIS)

In this work, isozyme and agromorphologic variability of radiation-induced rice mutants with different cytoplasm base was surveyed. Agromorphologic data (plant type, lodging resistance, life cycle and yielding) were transformed into binary data. This markers, along with isozyme (Peroxidases, Esterases, Catalases, Alcohol Dehydrogenases and Polyphenoloxidase) data, were considered for genetic diversity analyses in order to estimate the extent of diversity generated by ionizing radiation. Genetic Similarity between individuals was obtained based on Dice's Coefficient. The UPGMA phenogram defined three main clusters that clearly corresponded to the different cytoplasm sources. However, further discrimination between control varieties and their mutants could be obtained. Bootstrapping analysis was performed to estimate the robustness of the group in the phenogram. According to their bootstrap P value (99.6%), Basmati-370 mutant lines could be considered statistically different from their control. This analysis is suggested as an useful supporting tool for an accurate varietal validation. A Multiple Correspondence Analysis (MCA) showed individuals dispersion around the three principal axis of variation. In general the UPGMA phenogram pattern was corroborated at MCA. Variables such as life cycle, presence of bands Est-a and Prx-m and the absence of Est-i, Prx-h and Prx-i accounted for the higher contribution to variation. The adequacy of morphological and isozyme descriptors for new mutant lines validation is also discussed

191

Analysis and design of robust decentralized controllers for nonlinear systems  

Energy Technology Data Exchange (ETDEWEB)

Decentralized control strategies for nonlinear systems are achieved via feedback linearization techniques. New results on optimization and parameter robustness of non-linear systems are also developed. In addition, parametric uncertainty in large-scale systems is handled by sensitivity analysis and optimal control methods in a completely decentralized framework. This idea is applied to alleviate uncertainty in friction parameters for the gimbal joints on Space Station Freedom. As an example of decentralized nonlinear control, singular perturbation methods and distributed vibration damping are merged into a control strategy for a two-link flexible manipulator.

Schoenwald, D.A.

1993-07-01

192

Analysis and control design of two cascaded boost converter  

Directory of Open Access Journals (Sweden)

Full Text Available This work aims to study a cascade of two BOOST converters. First, a non- linear model of the whole controlled system is developed. Then, a robust non-linear controller of currents is synthesized using a backstepping design technique. A formal analysis based on Lyapunov stability and average theory is developed to describe the control currents loops performances. A classical PI controller is used for the voltages loops. The study of the stability of the system will also be discussed. Simulated results are displayed to validate the feasibility and the effectiveness of the proposed strategy.

Moutabir A.

2014-01-01

193

Task analysis methods applicable to control room design review (CDR)  

International Nuclear Information System (INIS)

This report presents the results of a research study conducted in support of the human factors engineering program of the Atomic Energy Control Board in Canada. It contains five products which may be used by the Atomic Enegy Control Board in relation to Task Analysis of jobs in CANDU nuclear power plants: 1. a detailed method for preparing for a task analysis; 2. a Task Data Form for recording task analysis data; 3. a detailed method for carrying out task analyses; 4. a guide to assessing alternative methods for performing task analyses, if such are proposed by utilities or consultants; and 5. an annotated bibliography on task analysis. In addition, a short explanation of the origins, nature and uses of task analysis is provided, with some examples of its cost effectiveness. 35 refs

194

REVIEW OF NRC APPROVED DIGITAL CONTROL SYSTEMS ANALYSIS  

Energy Technology Data Exchange (ETDEWEB)

Preliminary design concepts for the proposed Subsurface Repository at Yucca Mountain indicate extensive reliance on modern, computer-based, digital control technologies. The purpose of this analysis is to investigate the degree to which the U. S. Nuclear Regulatory Commission (NRC) has accepted and approved the use of digital control technology for safety-related applications within the nuclear power industry. This analysis reviews cases of existing digitally-based control systems that have been approved by the NRC. These cases can serve as precedence for using similar types of digitally-based control technologies within the Subsurface Repository. While it is anticipated that the Yucca Mountain Project (YMP) will not contain control systems as complex as those required for a nuclear power plant, the review of these existing NRC approved applications will provide the YMP with valuable insight into the NRCs review process and design expectations for safety-related digital control systems. According to the YMP Compliance Program Guidance, portions of various NUREGS, Regulatory Guidelines, and nuclear IEEE standards the nuclear power plant safety related concept would be applied to some of the designs on a case-by-case basis. This analysis will consider key design methods, capabilities, successes, and important limitations or problems of selected control systems that have been approved for use in the Nuclear Power industry. An additional purpose of this analysis is to provide background information in support of further development of design criteria for the YMP. The scope and primary objectives of this analysis are to: (1) Identify and research the extent and precedence of digital control and remotely operated systems approved by the NRC for the nuclear power industry. Help provide a basis for using and relying on digital technologies for nuclear related safety critical applications. (2) Identify the basic control architecture and methods of key digital control systems approved for use in the nuclear power industry by the NRC. (3) Identify and discuss key design issues, features, benefits, and limitations of these NRC approved digital control systems that can be applied as design guidance and correlated to the Monitored Geologic Repository (MGR) design requirements. (4) Identify codes and standards used in the design of these NRC approved digital control systems and discuss their possible applicability to the design of a subsurface nuclear waste repository. (5) Evaluate the NRC approved digital control system's safety, reliability and maintainability features and issues. Apply these to MGR design methodologies and requirements. (6) Provide recommendations for use in developing design criteria in the System Description Documents for the digital control systems of the subsurface nuclear waste repository at Yucca Mountain. (7) Develop recommendations for applying NRC approval methods for digital control systems for the subsurface nuclear waste repository at Yucca Mountain. This analysis will focus on the development of the issues, criteria and methods used and required for identifying the appropriate requirements for digital based control systems. Attention will be placed on development of recommended design criteria for digital controls including interpretation of codes, standards and regulations. Attention will also focus on the use of digital controls and COTS (Commercial Off-the-shelf) technology and equipment in selected NRC approved digital control systems, and as referenced in applicable codes, standards and regulations. The analysis will address design issues related to COTS technology and how they were dealt with in previous NRC approved digital control systems.

D.W. Markman

1999-09-17

195

Luminescence properties of Eu2+ in M2MgSi2O7 (M=Ca, Sr, and Ba) phosphors  

Science.gov (United States)

The photoluminescence properties of alkali-earth magnesium silicates (M2MgSi2O7, M=Ca, Sr, and Ba) doped with Eu2+ were investigated. Solid solutions of Ba x Sr2- x Si2O7, Ca2MgSi2O7, and Sr2MgSi2O7 were prepared. Ba x Sr2- x Si2O7 retained a tetragonal crystal structure similar to the structure of the other compounds up to a stoichiometry of x=1.6, which enabled a systematic study of the common structure. Monoclinic Ba2MgSi2O7 was prepared, and the luminescence properties were compared with those of other samples. The emission and excitation spectra of tetragonal M2MgSi2O7 (M=Ca, Sr, and Ba) changed as a function of the covalency, site symmetry, and crystal field strength. The luminescence properties showed excellent agreement with theoretical predictions based on these factors. The Stokes shift differentiated the emission behaviors of the tetragonal and monoclinic structures.

Kim, T.; Kim, Y.; Kang, S.

2012-03-01

196

Hybrid Formulations of Liposomes and Bioadhesive Polymers Improve the Hypotensive Effect of the Melatonin Analogue 5-MCA-NAT in Rabbit Eyes  

Science.gov (United States)

For the treatment of chronic ocular diseases such as glaucoma, continuous instillations of eye drops are needed. However, frequent administrations of hypotensive topical formulations can produce adverse ocular surface effects due to the active substance or other components of the formulation, such as preservatives or other excipients. Thus the development of unpreserved formulations that are well tolerated after frequent instillations is an important challenge to improve ophthalmic chronic topical therapies. Furthermore, several components can improve the properties of the formulation in terms of efficacy. In order to achieve the mentioned objectives, we have developed formulations of liposomes (150–200 nm) containing components similar to those in the tear film and loaded with the hypotensive melatonin analog 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT, 100 µM). These formulations were combined with mucoadhesive (sodium hyaluronate or carboxymethylcellulose) or amphiphilic block thermosensitive (poloxamer) polymers to prolong the hypotensive efficacy of the drug. In rabbit eyes, the decrease of intraocular pressure with 5-MCA-NAT-loaded liposomes that were dispersed with 0.2% sodium hyaluronate, 39.1±2.2%, was remarkably higher compared to other liposomes formulated without or with other bioadhesive polymers, and the effect lasted more than 8 hours. According to the results obtained in the present work, these technological strategies could provide an improved modality for delivering therapeutic agents in patients with glaucoma. PMID:25329636

Palma, Santiago; Allemandi, Daniel; Herrero-Vanrell, Rocio; Molina-Martinez, Irene T.

2014-01-01

197

Comparison of CEA, MCA, CA 15-3 and CA 27-29 in follow-up and monitoring therapeutic response in breast cancer patients.  

Science.gov (United States)

In order to define the most useful tumor marker panel in breast cancer patients' follow-up and in monitoring treatment response, serological levels of CEA, MCA, Ca 15-3 and Ca 27-29 were evaluated in 220 patients. 180 patients had no evidence of disease (NED) after primary treatment, and 40 had metastases at first diagnosis time; in a 4 years follow-up, 30 of the NED patients relapsed, and were then included in the group of metastatic patients subjected to anticancer treatment. Overall sensitivity in metastatic patients was: CEA 40%, MCA 35%, Ca 15-3 79%, Ca 27-29 70%, with the highest percentages and mean values in liver and bone localizations. Combination of Ca 15-3 and Ca 27-29 improved sensitivity in bone lesion (85% vs 80%), in locoregional relapses only association with CEA increased sensitivity (60% vs 40%). Ca 15-3 and Ca 27-29 values increased on average 3 months before clinical diagnosis. In treated patients there was a better correlation with a clinical course of disease for Ca 15-3 and Ca 27-29 (both 81%) as compared to the other determined markers. PMID:10629644

Lauro, S; Trasatti, L; Bordin, F; Lanzetta, G; Bria, E; Gelibter, A; Reale, M G; Vecchione, A

1999-01-01

198

Implementation of hazard analysis critical control point in jameed production.  

Science.gov (United States)

The average of standard plate count and coliforms, Staphylococcus aureus and Salmonella counts for three home-made jameed samples, a traditional fermented dairy product, before applying hazard analysis critical control point system were 2.1?×?10(3), 8.9?×?10(1), 4?×?10(1) and less than 10?cfu/g, respectively. The developed hazard analysis critical control point plan resulted in identifying ten critical control points in the flow chart of jameed production. The critical control points included fresh milk receiving, pasteurization, addition of starter, water and salt, straining, personnel hygiene, drying and packaging. After applying hazard analysis critical control point system, there was significant improvement in the microbiological quality of the home-made jameed. The standard plate count was reduced to 3.1?×?10(2)?cfu/g whereas coliform and Staphylococcus aureus counts were less than 10?cfu/g and Salmonella was not detected. Sensory evaluation results of color and flavor of sauce prepared from jameed showed a significant increase in the average scores given after hazard analysis critical control point application. PMID:22701056

Al-Saed, A K; Al-Groum, R M; Al-Dabbas, M M

2012-06-01

199

Design and Analysis of Morpheus Lander Flight Control System  

Science.gov (United States)

The Morpheus Lander is a vertical takeoff and landing test bed vehicle developed to demonstrate the system performance of the Guidance, Navigation and Control (GN&C) system capability for the integrated autonomous landing and hazard avoidance system hardware and software. The Morpheus flight control system design must be robust to various mission profiles. This paper presents a design methodology for employing numerical optimization to develop the Morpheus flight control system. The design objectives include attitude tracking accuracy and robust stability with respect to rigid body dynamics and propellant slosh. Under the assumption that the Morpheus time-varying dynamics and control system can be frozen over a short period of time, the flight controllers are designed to stabilize all selected frozen-time control systems in the presence of parametric uncertainty. Both control gains in the inner attitude control loop and guidance gains in the outer position control loop are designed to maximize the vehicle performance while ensuring robustness. The flight control system designs provided herein have been demonstrated to provide stable control systems in both Draper Ares Stability Analysis Tool (ASAT) and the NASA/JSC Trick-based Morpheus time domain simulation.

Jang, Jiann-Woei; Yang, Lee; Fritz, Mathew; Nguyen, Louis H.; Johnson, Wyatt R.; Hart, Jeremy J.

2014-01-01

200

Analysis of boron depletion in HTR control rod  

International Nuclear Information System (INIS)

The worth of control rod and its change along depletion are one of important features for reactor neutronics design. The control rods in pebble bed high-temperature gas-cooled reactor (HTR) were located in the hole of side graphite reflector. Its absorber was made up of annular B4C, which had special depletion rules. The depletion characteristics in each absorber sub-zone and the changes of the control rod worth were analyzed, based on both the MCNP coupling another depletion module and the detailed modeling control rod absorber region. According to the analysis, the boron in inner region of absorber is depleted only a little, although most of boron in outer region of absorber is depleted, because of the strong space self-shielding effects in control rod absorber. Therefore, the worth of control rod in the HTR decreases just a little at the end of reactor life time. (authors)

 
 
 
 
201

Stability and Sensitivity Analysis of Fuzzy Control Systems. Mechatronics Applications  

Directory of Open Access Journals (Sweden)

Full Text Available The development of fuzzy control systems is usually performed by heuristicmeans, incorporating human skills, the drawback being in the lack of general-purposedevelopment methods. A major problem, which follows from this development, is theanalysis of the structural properties of the control system, such as stability, controllabilityand robustness. Here comes the first goal of the paper, to present a stability analysismethod dedicated to fuzzy control systems with mechatronics applications based on the useof Popov’s hyperstability theory. The second goal of this paper is to perform the sensitivityanalysis of fuzzy control systems with respect to the parametric variations of the controlledplant for a class of servo-systems used in mechatronics applications based on theconstruction of sensitivity models. The stability and sensitivity analysis methods provideuseful information to the development of fuzzy control systems. The case studies concerningfuzzy controlled servo-systems, accompanied by digital simulation results and real-timeexperimental results, validate the presented methods.

Radu-Emil Precup

2006-01-01

202

Performance Analysis of PCFICH and PDCCH LTE Control Channels  

Directory of Open Access Journals (Sweden)

Full Text Available Control channels play a key role in the evaluation of mobile system performance. The purpose of our paper is to evaluate the performance of the control channels implementation in the Long Term Evolution (LTE system. The paper deals with the simulation of the complete signal processing chain for Physical Control Format Indicator Channel (PCFICH and Physical Downlink Control Channel (PDCCH in the LTE system, Release 8. We implemented a complete signal processing chain for downlink control channels as an extension of the existing MATLAB LTE downlink simulator. The paper presents results of PCFICH and PDCCH control channel computer performance analysis in various channel conditions. The results can be compared with the performance of data channels.

J. Milos

2014-04-01

203

21 CFR 120.8 - Hazard Analysis and Critical Control Point (HACCP) plan.  

Science.gov (United States)

...Hazard Analysis and Critical Control Point (HACCP) plan. 120.8 Section 120.8 ...HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120...Hazard Analysis and Critical Control Point (HACCP) plan. (a) HACCP plan. Each...

2010-04-01

204

21 CFR 120.8 - Hazard Analysis and Critical Control Point (HACCP) plan.  

Science.gov (United States)

...2010-04-01 2010-04-01 false Hazard Analysis and Critical Control Point...CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT...SYSTEMS General Provisions § 120.8 Hazard Analysis and Critical Control...

2010-04-01

205

Cluster Analysis of A Tobacco Control Data Set  

Directory of Open Access Journals (Sweden)

Full Text Available Development of theoretical and methodological frameworks in data analysis is fundamental for modeling complex tobacco control systems. Following this idea, a new optimization based approach was introduced in the paper through two distinct methods: the modified linear least square fit and a heuristic algorithm for feature selection based on optimization techniques. Compared with traditional statistical techniques, optimization-based methods have the potential to detect nonlinearity, and therefore to be more effective analysis tools of complex data set. In this study we evaluate the modified global k-means clustering algorithm by applying it to a massive set of real-time tobacco control survey data. Cluster analysis identified fixed and stable clusters in the studied data. These clusters correspond to groups of smokers with similar behavior and the identification of these clusters may allow us to give recommendations on modification of existing tobacco control systems and on the design of future data acquisition surveys.

Z. Dzalilov

2010-12-01

206

Analysis of communication based distributed control of MMC for HVDC  

DEFF Research Database (Denmark)

Modular Multilevel Converter (MMC) has gained a lot of interest in industry in the recent years due to its modular design and easy adaption for applications that require different power and voltage level. However, the control and operation of a real MMC consisting of large number of sub modules for high power and high voltage application is a very challenging task. For the reason that distributed control architecture could maintain the modularity of the MMC, this control architecture will be investigated and a distributed control system dedicated for MMC will be proposed in this paper. The suitable communication technologies, modulation and control techniques for the proposed distributed control system are discussed and compared. Based on the frequency domain modeling and analysis of the distributed control system, the controllers of the different control loops are designed by analytical methods and Matlab tools. Finally, sensitiveness of the distributed control system to modulation effect (phase-shifted PWM), communication delay, individual carrier frequency and sampling frequency is studied through simulations that are made in Matlab Simulink and PLECS.

Huang, Shaojun; Teodorescu, Remus

2013-01-01

207

Concurrent analysis of choice and control in childbirth  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background This paper reports original research on choice and control in childbirth. Eight women were interviewed as part of a wider investigation into locus of control in women with pre-labour rupture of membranes at term (PROM) 1. Methods The following study uses concurrent analysis to sample and analyse narrative aspects of relevant literature along with these interviews in order to synthesise a generalisable ...

Martin Caroline; Jomeen Julie; Martin Colin; Snowden Austyn

2011-01-01

208

Decentralized, cooperative control of multivehicle systems: Design and stability analysis  

Science.gov (United States)

This dissertation addresses the design and stability analysis of decentralized, cooperative control laws for multivehicle systems. Advances in communication, navigation, and surveillance systems have enabled greater autonomy in multivehicle systems, and there is a shift toward decentralized, cooperative systems for computational efficiency and robustness. In a decentralized control scheme, control inputs are determined onboard each vehicle; therefore, decentralized controllers are more efficient for large numbers of vehicles, and the system is more robust to communication failures and reconfiguration. The design of decentralized, cooperative control laws is explored for a nonlinear vehicle model that can be represented in a double-integrator form. Cooperative controllers are functions of spacing errors with respect to other vehicles in the system, where the communication structure defines the information that is available to each vehicle. Control inputs are selected to achieve internal stability, or zero steady-state spacing errors, between vehicles in the system. Closed-loop equations of motion for the cooperative system can be written in a structural form, where damping and stiffness matrices contain control gains acting on the velocity and positions of the vehicles, respectively. The form of the stiffness matrix is determined by the communication structure, where different communication structures yield different control forms. Communication structures are compared using two structural analysis tools: modal cost and frequency-response functions, which evaluate the response of the multivehicle systems to disturbances. The frequency-response information is shown to reveal the string stability of different cooperative control forms. The effects of time delays in the feedback states of the cooperative control laws on system stability are also investigated. Closed-loop equations of motion are modeled as delay differential equations, and two stability notions are presented: delay-independent and delay-dependent stability. Lastly, two additional cooperative control forms are investigated. The first control form spaces vehicles along an arbitrary path, where distances between vehicles are constant for a given spacing parameter. This control form shows advantages over spacing vehicles using control laws designed in an inertial frame. The second control form employs a time-based spacing scheme, which spaces vehicles at constant-time intervals at a desired endpoint. The stability of these control forms is presented.

Weitz, Lesley Anne

209

Decision analysis for boiling water reactor oxygen control  

International Nuclear Information System (INIS)

The project has three primary phases: development of a cracking incident data base, development of a decision model incorporating probable failure rates and life-cycle economic analysis, and execution of sensitivity studies. Several sensitivity studies are planned, measuring the effects of relative degree of material sensitization and uncertainties in failure rates after oxygen control, repair and replacement costs, and economic analysis parameters. These studies are expected to highlight critical data needs and help identify high payoff areas for additional research

210

Analysis and control of an anaerobic upflow Fixed bed bioreactor  

International Nuclear Information System (INIS)

This paper presents the bifurcation analysis in an anaerobic upflow fixed bed bioreactor, which is an anaerobic digestion system useful for wastewater treatment. In the dynamic analysis part, the equilibrium points, linear stability and bifurcation curves are studied, focusing in the washout condition. For the self tuning regulator the parameter estimation and control law are designed, and an integral action is introduced in order to address the disturbances. The simulation studies show the improvement of the performance when a disturbance appears.

211

Economic Analysis of Corrosion Control In Petroleum Refineries  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Economic analysis of corrosion problems and their prevention or control was found to gain very little importance in the last 10 years according to the published work surveyed. This article surveys the most important work in this area and shows the magnitude of corrosion problems as cost analysis measures indicate. It also refers to the need for continuous research in this field of vital importance in the coming era. Data from several sources have been tabulated to highlight the magnitud...

Salem, A. B.

1988-01-01

212

Using the Prony Analysis for Assessing Servo Drive Control  

Directory of Open Access Journals (Sweden)

Full Text Available The Prony Analysis is already used in different fields of science and industries. The described new approach intends assessing the performance of Servo Drive Control. The basic approach is, that two important dynamic parameters of closed loop behavior, damping and frequency, are estimated by the Prony method. Hence analyzing a control loop in this way leads to a statement concerning the quality of control and allows comparing different parameter sets. The paper presents results achieved by using this method on a test rig.

Reimund Neugebauer

2011-10-01

213

The TARA control, data acquisition and analysis system  

International Nuclear Information System (INIS)

The MIT tandem mirror (TARA) control, data acquisition and analysis system consists of two major parts: 1) a Gould 584 industrial programmable controller (PC) to control engineering functions; and 2) a VAX 11/750 based data acquisition and analysis system for physics analysis. The PC is designed for use in harsh industrial environments and has proven to be a reliable and cost-effective means for automated control. The PC configuration is dedicated to control tasks on the TARA magnet, vacuum, RF, neutral beam, diagnostics, and utility systems. The data transfer functions are used to download system operating parameters from menu selectable tables. Real time status reports are provided to video terminals and as blocks of data to the host computer for storage. The data acquisition and analysis system for TARA was designed to provide high throughput and ready access to data from earlier runs. The adopted design uses pre-existing software packages in a system which is simple, coherent, fast, and which requires a minimum of new software development. The computer configuration is a VAX 11/750 running VMS with 124 M byte massbus disk and 1.4 G byte unibus disk subsystem. The front end for the data system is a Kinetic Systems CAMAC serial highway interface, and the graphics I/O is done through a DMA terminal multiplexer. The data system provides a set of standard tools for use in user-written analysis programs. These tools allow access to current shot data as well as to past shots with a minimum of overhead. The acquisition, archival, basic analysis, and display of 1 M byte of data for every shot is accomplished once every 3-5 minutes, and any shot may be easily reanalyzed

214

Development of ADOCS controllers and control laws. Volume 2: Literature review and preliminary analysis  

Science.gov (United States)

The Advanced Cockpit Controls/Advanced Flight Control System (ACC/AFCS) study was conducted by the Boeing Vertol Company as part of the Army's Advanced Digital/Optical Control System (ADOCS) program. Specifically, the ACC/AFCS investigation was aimed at developing the flight control laws for the ADOCS demonstrator aircraft which will provide satisfactory handling qualities for an attack helicopter mission. The three major elements of design considered are as follows: Pilot's integrated Side-Stick Controller (SSC) -- Number of axes controlled; force/displacement characteristics; ergonomic design. Stability and Control Augmentation System (SCAS)--Digital flight control laws for the various mission phases; SCAS mode switching logic. Pilot's Displays--For night/adverse weather conditions, the dynamics of the superimposed symbology presented to the pilot in a format similar to the Advanced Attack Helicopter (AAH) Pilot Night Vision System (PNVS) for each mission phase as a function of ACAS characteristics; display mode switching logic. Findings from the literature review and the analysis and synthesis of desired control laws are reported in Volume 2. Conclusions drawn from pilot rating data and commentary were used to formulate recommendations for the ADOCS demonstrator flight control system design. The ACC/AFCS simulation data also provide an extensive data base to aid the development of advanced flight control system design for future V/STOL aircraft.

Landis, Kenneth H.; Glusman, Steven I.

1985-01-01

215

Analysis of Effectiveness of Phoenix Entry Reaction Control System  

Science.gov (United States)

Interaction between the external flowfield and the reaction control system (RCS) thruster plumes of the Phoenix capsule during entry has been investigated. The analysis covered rarefied, transitional, hypersonic and supersonic flight regimes. Performance of pitch, yaw and roll control authority channels was evaluated, with specific emphasis on the yaw channel due to its low nominal yaw control authority. Because Phoenix had already been constructed and its RCS could not be modified before flight, an assessment of RCS efficacy along the trajectory was needed to determine possible issues and to make necessary software changes. Effectiveness of the system at various regimes was evaluated using a hybrid DSMC-CFD technique, based on DSMC Analysis Code (DAC) code and General Aerodynamic Simulation Program (GASP), the LAURA (Langley Aerothermal Upwind Relaxation Algorithm) code, and the FUN3D (Fully Unstructured 3D) code. Results of the analysis at hypersonic and supersonic conditions suggest a significant aero-RCS interference which reduced the efficacy of the thrusters and could likely produce control reversal. Very little aero-RCS interference was predicted in rarefied and transitional regimes. A recommendation was made to the project to widen controller system deadbands to minimize (if not eliminate) the use of RCS thrusters through hypersonic and supersonic flight regimes, where their performance would be uncertain.

Dyakonov, Artem A.; Glass, Christopher E.; Desai, Prasun, N.; VanNorman, John W.

2008-01-01

216

A new TXRF vacuum chamber with sample changer for chemical analysis using silicon drift chamber detector  

International Nuclear Information System (INIS)

Full text: Several TXRF spectrometers for chemical analysis as well as for wafer surface analysis are commercially available. But there is no one available for chemical analysis offering the possibility to measure the samples in vacuum conditions. Vacuum of 10-2 mbar in the sample environment helps to reduce the background due to scattering from air, thus to improve the detection limits as well as to reduce the absorption of low energy fluorescence radiation from low Z elements and extend the elemental range to be measured and removes the Ar lines from the spectrum. The x-ray group of the Atominstitut designed and fabricated a new vacuum chamber for TXRF equipped with a 12 position sample changer from Italstructures, Riva, Italy. The detector used was a 10 mm2 silicon drift detector (KETEK, Munich, Germany), offering the advantage of electrically cooling, so no LN2 is required. The chamber was designed to be attached to a diffraction tube housing, e.g. with a fine focus Mo-x-ray tube and uses a multilayer monochromator. Spectra are stored by a small AMTEK MCA and control between sample changer and MCA communication is done by a modified AMPTEK software. The performance is expressed in detection limits of 1 pg Rb for Mo Ka excitation with 50 kV, 40 mA excitation conditions, 1000 s lifetime, obtained from a sample containing 600 pg Rb as single element standard. Details on performance, reproducibility and light element excitation and detection are presented. (author)

217

Control rod repositioning considerations in core design analysis  

International Nuclear Information System (INIS)

Control rod repositioning is a method for minimizing rod cluster control assembly (RCCA) wear in the upper internals area where the guide cards interface with the rodlets of the RCCAs. A number of utilities have implemented strategies for rod repositioning, which often has no impact on the nuclear analysis for cases where the control rods are never repositioned into the active fuel. Other strategies involve repositioning the control rods several steps into the active fuel. The impact of this type of repositioning on the axial power shape and consequently the total peaking factor FQT varies, depending on the method in which the repositioning is implemented at the plant. Operating for long periods with all the control and shutdown rods inserted several steps in the active fuel followed by withdrawing them fully from the core results in a shifting of the power distribution toward the top of the core and must be accounted for in the design analysis. On the other hand, an optional plan for control rod repositioning that considers margins available in related design parameters can be devised that minimizes the effects of the repositioning for the reload. This paper summarizes a rod repositioning strategy implemented for a recent reload and some calculated power shape results for this strategy and other scenarios

218

A Calculus for Control Flow Analysis of Security Protocols  

DEFF Research Database (Denmark)

The design of a process calculus for anaysing security protocols is governed by three factors: how to express the security protocol in a precise and faithful manner, how to accommodate the variety of attack scenarios, and how to utilise the strengths (and limit the weaknesses) of the underlying analysis methodology. We pursue an analysis methodology based on control flow analysis in flow logic style and we have previously shown its ability to analyse a variety of security protocols. This paper develops a calculus, LysaNS that allows for much greater control and clarity in the description of attack scenarios, that gives a more flexible format for expressing protocols, and that at the same time allows to circumvent some of the ``false positives'' arising in previous work.

Buchholtz, Mikael; Nielson, Hanne Riis

2004-01-01

219

Quantitative cerebral perfusion assessment using microscope-integrated analysis of intraoperative indocyanine green fluorescence angiography versus positron emission tomography in superficial temporal artery to middle cerebral artery anastomosis  

Science.gov (United States)

Background: Intraoperative qualitative indocyanine green (ICG) angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS) after STA-MCA anastomosis. Methods: Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs) on the cortex, corresponding to ROIs on positron emission tomography (PET) study, was recorded. Maximum intensity (IMAX), cerebral blood flow index (CBFi), rise time (RT), and time to peak (TTP) were evaluated. Results: RT/TTP, but not IMAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01) with mean transit time (MTT)/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland–Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017). The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017). Conclusions: Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative HPS.

Kobayashi, Shinya; Ishikawa, Tatsuya; Tanabe, Jun; Moroi, Junta; Suzuki, Akifumi

2014-01-01

220

Page: a program for gamma spectra analysis in PC microcomputers  

International Nuclear Information System (INIS)

PAGE is a software package, written in BASIC language, to perform gamma spectra analysis. It was developed to be used in a high-purity intrinsic germanium detector-multichannel analyser-PC microcomputer system. The analysis program of PAGE package accomplishes functions as follows: peak location; gamma nuclides identification; activity determination. Standard nuclides sources were used to calibrate the system. To perform the efficiency x energy calibration a logarithmic fit was applied. Analysis of nuclides with overlapping peaks is allowed by PAGE program. PAGE has additional auxiliary programs for: building and list of isotopic nuclear data libraries; data acquisition from multichannel analyser; spectrum display with automatic area and FWHM determinations. This software is to be applied in analytical process control where time response is a very important parameter. PAGE takes ca. 1.5 minutes to analyse a complex spectrum from a 4096 channels MCA. (author)

 
 
 
 
221

Stability Analysis and Design of Impulsive Control Lorenz Systems Family  

International Nuclear Information System (INIS)

Lorenz systems family unifying Lorenz system, Chen system and Lue system is a typical chaotic family. In this paper, we consider impulsive control Lorenz chaotic systems family with time-varying impulse intervals. By establishing an effective tool of a set of inequalities, we analyze the asymptotic stability of impulsive control Lorenz systems family and obtain some new less conservative conditions. Based on the stability analysis, we design a novel impulsive controller with time-varying impulse intervals. Illustrative examples are provided to show the feasibility and effectiveness of our method. The obtained results not only can be used to design impulsive control for Lorenz systems family, but also can be extended to other chaotic systems. (general)

222

Ordinary differential equations analysis, qualitative theory and control  

CERN Document Server

The book comprises a rigorous and self-contained treatment of initial-value problems for ordinary differential equations. It additionally develops the basics of control theory, which is a unique feature in the current textbook literature. The following topics are particularly emphasised: • existence, uniqueness and continuation of solutions, • continuous dependence on initial data, • flows, • qualitative behaviour of solutions, • limit sets, • stability theory, • invariance principles, • introductory control theory, • feedback and stabilization. The last two items cover classical control theoretic material such as linear control theory and absolute stability of nonlinear feedback systems. It also includes an introduction to the more recent concept of input-to-state stability. Only a basic grounding in linear algebra and analysis is assumed. Ordinary Differential Equations will be suitable for final year undergraduate students of mathematics and appropriate for beginning postgraduates in math...

Logemann, Hartmut

2014-01-01

223

Experimental Bifurcation Analysis By Control-based Continuation - Determining Stability’  

DEFF Research Database (Denmark)

The newly developed control-based continuation technique has made it possible to perform experimental bifurcation analysis, e.g. to track stable as well as unstable branches of frequency responses directly in experiments. The method bypasses mathematical models, and systematically explores how vibration characteristics of dynamical systems change under variation of parameters. The method employs a control scheme to modify the response stability. While this facilitates exploration of the unstable branches of a bifurcation diagram, it unfortunately makes it impossible to distinguish previously stable and unstable equilibrium states. We present the ongoing work of developing and applying the control-based continuation method to an experimental mechanical test-rig, consisting of a harmonically forced nonlinear impact oscillator controlled by electromagnetic actuators. Furthermore we propose and test ideas on how to determine the stability of equilibria states during continuation.

Bureau, Emil; Santos, Ilmar

2012-01-01

224

Simulating labeling to estimate kinetic parameters for flux control analysis.  

Science.gov (United States)

An important aspect of kinetic modeling is the ability to provide predictive information on network control and dynamic responses to genetic or environmental perturbations based on innate enzyme kinetics. In a top-down approach to model assembly, unknown kinetic parameters are calculated using experimental data such as metabolite pool concentrations and transient labeling patterns after supply of an isotopically labeled substrate. These kinetic parameters can then be used to calculate flux control coefficients for every reaction in a network, which aids in the identification of enzymatic reactions that exert the most control over the network as a whole. This chapter describes a modeling approach to estimate kinetic parameters which are then used to perform metabolic control analysis. An example is provided for the benzenoid network of Petunia hybrida; however, the methodologies can be applied to any small segment of metabolism. PMID:24222418

Marshall-Colon, Amy; Sengupta, Neelanjan; Rhodes, David; Morgan, John A

2014-01-01

225

Preliminary control system design and analysis for the Space Station Furnace Facility thermal control system  

Science.gov (United States)

This report presents the Space Station Furnace Facility (SSFF) thermal control system (TCS) preliminary control system design and analysis. The SSFF provides the necessary core systems to operate various materials processing furnaces. The TCS is defined as one of the core systems, and its function is to collect excess heat from furnaces and to provide precise cold temperature control of components and of certain furnace zones. Physical interconnection of parallel thermal control subsystems through a common pump implies the description of the TCS by coupled nonlinear differential equations in pressure and flow. This report formulates the system equations and develops the controllers that cause the interconnected subsystems to satisfy flow rate tracking requirements. Extensive digital simulation results are presented to show the flow rate tracking performance.

Jackson, M. E.

1995-01-01

226

The Use of Multiple Correspondence Analysis to Explore Associations between Categories of Qualitative Variables in Healthy Ageing  

Science.gov (United States)

The main focus of this study was to illustrate the applicability of multiple correspondence analysis (MCA) in detecting and representing underlying structures in large datasets used to investigate cognitive ageing. Principal component analysis (PCA) was used to obtain main cognitive dimensions, and MCA was used to detect and explore relationships between cognitive, clinical, physical, and lifestyle variables. Two PCA dimensions were identified (general cognition/executive function and memory), and two MCA dimensions were retained. Poorer cognitive performance was associated with older age, less school years, unhealthier lifestyle indicators, and presence of pathology. The first MCA dimension indicated the clustering of general/executive function and lifestyle indicators and education, while the second association was between memory and clinical parameters and age. The clustering analysis with object scores method was used to identify groups sharing similar characteristics. The weaker cognitive clusters in terms of memory and executive function comprised individuals with characteristics contributing to a higher MCA dimensional mean score (age, less education, and presence of indicators of unhealthier lifestyle habits and/or clinical pathologies). MCA provided a powerful tool to explore complex ageing data, covering multiple and diverse variables, showing if a relationship exists and how variables are related, and offering statistical results that can be seen both analytically and visually. PMID:24222852

Costa, Patricio Soares; Santos, Nadine Correia; Cunha, Pedro; Cotter, Jorge; Sousa, Nuno

2013-01-01

227

Assessment of cerebral blood flow reserve using blood oxygen level-dependent echo planar imaging after acetazolamide administration in patients post-STA-MCA anastomosis surgery  

International Nuclear Information System (INIS)

Recently, blood oxygen level-dependent (BOLD) echo planar imaging (EPI) has been used to estimate blood flow changes. Theoretically, a relative decrement of deoxyhemoglobin in cerebral blood supply induces a MR signal change after neuronal stimulation. In the present study, we have attempted to evaluate CBF reserve capacity by the BOLD EPI in patients who had undergone STA-MCA anastomosis surgery. Then, we compared with the signal intensity changes obtained by this procedure with the CBF changes by Xe-SPECT after acetazolamide administration. Six patients, post-STA-MCA anastomosis surgery, were studied. Pre-operatively, MR signal intensity and CBF, by Xe-SPECT, were increased in the intact side after acetazolamide administration in all patients, and MR signal intensities were decreased in low flow regions after acetazolamide administration in all four patients in whom so-called steal phenomenon was demonstrated by Xe-SPECT study. Post-operatively, poor response was shown after acetazolamide administration with both Xe-SPECT and BOLD EPI in the two patients who had unsuccessful anastomoses. In the successfully anastomosed patients, improved vascular reactivity was demonstrated on BOLD EPI after acetazolamide administration in 3 of 4 patients in whom an improvement of vascular reactivity was demonstrated on Xe-SPECT. In one patient, MRI studies were considered to have technical artifacts, because the MR signal intensity did not increase, even in the intact side after acetazolamide administration. In conclusion, BOLD EPI after acetazolamide administration is an useful procedure for the pre- and post-operative of vascular reserve in patients with ischemic stroke. (author)

228

Assessment of cerebral blood flow reserve using blood oxygen level-dependent echo planar imaging after acetazolamide administration in patients post-STA-MCA anastomosis surgery  

Energy Technology Data Exchange (ETDEWEB)

Recently, blood oxygen level-dependent (BOLD) echo planar imaging (EPI) has been used to estimate blood flow changes. Theoretically, a relative decrement of deoxyhemoglobin in cerebral blood supply induces a MR signal change after neuronal stimulation. In the present study, we have attempted to evaluate CBF reserve capacity by the BOLD EPI in patients who had undergone STA-MCA anastomosis surgery. Then, we compared with the signal intensity changes obtained by this procedure with the CBF changes by Xe-SPECT after acetazolamide administration. Six patients, post-STA-MCA anastomosis surgery, were studied. Pre-operatively, MR signal intensity and CBF, by Xe-SPECT, were increased in the intact side after acetazolamide administration in all patients, and MR signal intensities were decreased in low flow regions after acetazolamide administration in all four patients in whom so-called steal phenomenon was demonstrated by Xe-SPECT study. Post-operatively, poor response was shown after acetazolamide administration with both Xe-SPECT and BOLD EPI in the two patients who had unsuccessful anastomoses. In the successfully anastomosed patients, improved vascular reactivity was demonstrated on BOLD EPI after acetazolamide administration in 3 of 4 patients in whom an improvement of vascular reactivity was demonstrated on Xe-SPECT. In one patient, MRI studies were considered to have technical artifacts, because the MR signal intensity did not increase, even in the intact side after acetazolamide administration. In conclusion, BOLD EPI after acetazolamide administration is an useful procedure for the pre- and post-operative of vascular reserve in patients with ischemic stroke. (author)

Zenke, Kiichiro; Kusunoki, Katsusuke; Saito, Masahiro; Sadamoto, Kazuhiko [Washokai Sadamoto Hospital, Uwajima, Ehime (Japan); Ohta, Shinsuke; Kumon, Yoshiaki; Sakaki, Saburo; Nagasawa, Kiyoshi

1998-12-01

229

Crystal structures and chemistry of double perovskites Ba2M(II)M'(VI)O6 (M=Ca, Sr, M'=Te, W, U)  

International Nuclear Information System (INIS)

Structures of the double perovskites Ba2M(II)M '(VI)O6 (M=Ca, Sr, M'=Te, W, U) at room temperature have been investigated by the Rietveld method using X-ray and neutron powder diffraction data. For double perovskites with M=Sr, the observed space groups are I2/m (M' =W) and R3-bar (M'=Te), respectively. In the case of M=Ca, the space groups are either monoclinic P21/n (M'=U) or cubic Fm3-bar m (M'=W and Te). The tetragonal and orthorhombic symmetry reported earlier for Ba2SrTeO6 and Ba2CaUO6, respectively, were not observed. In addition, non-ambient X-ray diffraction data were collected and analyzed for Ba2SrWO6 and Ba2CaWO6 in the temperature range between 80 and 723 K. It was found that the rhombohedral R3-bar structure exists in Ba2SrWO6 above room temperature between the monoclinic and the cubic structure, whereas the cubic Ba2CaWO6 undergoes a structural phase transition at low temperature to the tetragonal I4/m structure. - Graphical abstract: Evolution of structures as function of temperature in Ba2SrWO6 (left) and Ba2CaWO6 (right). The existence of two phase region in Ba2SrWO6 can be clearly seen by the progressive increase of the rhombohedral R3-bar phase marked by asterisk (*)

230

Rescue localized intra-arterial thrombolysis for hyperacute MCA ischemic stroke patients after early non-responsive intravenous tissue plasminogen activator therapy  

Energy Technology Data Exchange (ETDEWEB)

The outcome of patients who show no early response to intravenous (i.v.) tissue plasminogen activator (tPA) therapy is poor. The objective of this study was to evaluate the feasibility of rescue localized intra-arterial thrombolysis (LIT) therapy for acute ischemic stroke patients after an early non-responsive i.v. tPA therapy. Patients with proximal MCA occlusions who were treated by LIT (n=10) after failure of early response [no improvement or improvement of National Institute of Health Stroke Scale (NIHSS) scores of {<=}3] to i.v. tPA therapy (0.9 mg/kg - 10% bolus and 90% i.v. infusion over 60 min) were selected. The recanalization rates, incidence of post-thrombolysis hemorrhage and clinical outcomes [baseline and discharge NIHSS scores, mortality, 3 months Barthel index (BI) and modified Rankin score (mRS)] were evaluated. Rescue LIT therapy was performed on ten MCA occlusion patients (male:female=3:7, mean age 71 years). The mean time between the initiation of i.v. tPA therapy and the initiation of intra-arterial urokinase (i.a. UK) was 117{+-}25.0 min [time to i.v. tPA 137{+-}32 min; time to digital subtraction angiography (DSA) 221{+-}42 min; time to i.a. UK 260{+-}46 min]. The baseline NIHSS scores showed significant improvement at discharge (median from 18 to 6). Symptomatic hemorrhage and, consequent, mortality were noted in 2/10 (20%) patients. Three months good outcome was noted in 4/10 (40%, mRS 0-2) and 3/10 (30%, BI {>=}95). In conclusion, rescue LIT therapy can be considered as a treatment option for patients not showing early response to full dose i.v. tPA therapy. Larger scale studies for further validation of this protocol may be necessary. (orig.)

Kim, Dong Joon; Kim, Dong Ik [Yonsei University College of Medicine, Department of Diagnostic Radiology, Seoul (Korea); Kim, Seo Hyun [Yonsei University Wonju College of Medicine, Department of Neurology, Wonju (Korea); Lee, Kyung Yeol [Yong Dong Severance Hospital, Department of Neurology, Seoul (Korea); Heo, Ji Hoe; Han, Sang Won [Yonsei University College of Medicine, Department of Neurology, Seoul (Korea)

2005-08-01

231

Rescue localized intra-arterial thrombolysis for hyperacute MCA ischemic stroke patients after early non-responsive intravenous tissue plasminogen activator therapy  

International Nuclear Information System (INIS)

The outcome of patients who show no early response to intravenous (i.v.) tissue plasminogen activator (tPA) therapy is poor. The objective of this study was to evaluate the feasibility of rescue localized intra-arterial thrombolysis (LIT) therapy for acute ischemic stroke patients after an early non-responsive i.v. tPA therapy. Patients with proximal MCA occlusions who were treated by LIT (n=10) after failure of early response [no improvement or improvement of National Institute of Health Stroke Scale (NIHSS) scores of ?3] to i.v. tPA therapy (0.9 mg/kg - 10% bolus and 90% i.v. infusion over 60 min) were selected. The recanalization rates, incidence of post-thrombolysis hemorrhage and clinical outcomes [baseline and discharge NIHSS scores, mortality, 3 months Barthel index (BI) and modified Rankin score (mRS)] were evaluated. Rescue LIT therapy was performed on ten MCA occlusion patients (male:female=3:7, mean age 71 years). The mean time between the initiation of i.v. tPA therapy and the initiation of intra-arterial urokinase (i.a. UK) was 117±25.0 min [time to i.v. tPA 137±32 min; time to digital subtraction angiography (DSA) 221±42 min; time to i.a. UK 260±46 min]. The baseline NIHSS scores showed significant improvement at discharge (median from 18 to 6). Symptomatic hemorrhage and, consequent, mortality were noted in 2/10 (20%) patients. Three months good outcome was noted in 4/10 (40%, mRS 0-2) and 3/10 (30%, BI ?95). In conclusion, rescue LIT therapy ca conclusion, rescue LIT therapy can be considered as a treatment option for patients not showing early response to full dose i.v. tPA therapy. Larger scale studies for further validation of this protocol may be necessary. (orig.)

232

ECONOMIC ANALYSIS, ROOT CONTROL, AND BACKWATER FLOW CONTROL AS RELATED TO INFILTRATION/INFLOW CONTROL. APPENDICES  

Science.gov (United States)

A study was conducted to identify and analyze present practices for determining and controlling infiltration and inflow (I/I) and investigate the role of roots and tide or backwater gates in the I/I problem. It was found through on-site investigations and questionnaires that loca...

233

ECONOMIC ANALYSIS, ROOT CONTROL, AND BACKWATER FLOW CONTROL AS RELATED TO INFILTRATION/INFLOW CONTROL  

Science.gov (United States)

A study was conducted to identify and analyze present practices for determining and controlling infiltration and inflow (I/I) and investigate the role of roots and tide or backwater gates in the I/I problem. It was found through on-site investigations and questionnaires that loca...

234

Concurrent analysis of choice and control in childbirth  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background This paper reports original research on choice and control in childbirth. Eight women were interviewed as part of a wider investigation into locus of control in women with pre-labour rupture of membranes at term (PROM 1. Methods The following study uses concurrent analysis to sample and analyse narrative aspects of relevant literature along with these interviews in order to synthesise a generalisable analysis of the pertinent issues. The original PROM study had found that women experienced a higher degree of control in hospital, a finding that appeared at odds with contemporary notions of choice. However, this paper contextualises this finding by presenting narratives that lucidly subscribe to the dominant discourse of hospital as the safest place to give birth, under the premise of assuring a live healthy baby irrespective of their management type. Results This complex narrative is composed of the following themes: 'perceiving risk', 'being prepared', 'reflecting on experience', maintaining control' and relinquishing control'. These themes are constructed within and around the medical, foetocentric, risk averse cultural context. Primary data are presented throughout to show the origins and interconnected nature of these themes. Conclusions Within this context it is clear that there is a highly valued role for competent health professionals that respect, understand and are capable of facilitating genuine choice for women.

Martin Caroline

2011-06-01

235

Electromagnetic analysis of control element drive mechanism for KSNP  

International Nuclear Information System (INIS)

The magnetic jack type Control Element Drive Mechanism (CEDM) for Korean Standard Nuclear Power Plant (KSNP) is an electromechanical device which provides controlled linear motion to the Control Element Assembly (CEA) through the Extension Shaft Assembly (ESA) in response to operational signals received from the Control Element Drive Mechanism Control System (CEDMCS). The CEDM is operated by applying localized magnetic flux fields to movable latch and lift magnets, which are in the coolant pressure boundary. The CEDM design had been developed through electromechanical testing of the system including the magnetic force lifting the ESA. But it will be inefficient if parametric studies should be performed to improve the CEDM by test due to the consumption of high cost and long duration. So it becomes necessary to develop a computational model to simulate the electromagnetic characteristics of the CEDM to improve the CEDM design efficiently. In this paper, the electromagnetic analysis using a 2D finite element model has been carried out to simulate magnetic force of the lift magnet of the CEDM, to provide effective evaluation between leakage flux and lift force and to compare with test results. Analysis results show the lift force satisfied the test results and design requirement and the lift force depend on the shape of the components, leakage flux and B-H curve

236

Impact of JIT on Quality Control Cost: A Sensitivity Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Many authors have been developed the models to study the influence of JIT on inventory. On other hand, strategic impact of JIT on quality control cost has not been clear-cut. The purpose of this paper is to study the impact of JIT on quality control by developing a model. The developed model is illustrated though a sensitivity analysis and a numeric example so that more attention could be provided on the most critical input parameters of model. The framework developed in this paper provides a step forward towards better planning for quality under JIT context.

Vikas Kumar

2014-04-01

237

Analysis of Droop Controlled Parallel Inverters in Islanded Microgrids  

DEFF Research Database (Denmark)

Three-phase droop controlled inverters are widely used in islanded microgrids to interface distributed energy resources and to provide for the loads active and reactive powers demand. The assessment of microgrids stability, affected by the control and line parameters, is a stringent issue. This paper shows a systematic approach to derive a closed loop model of the microgrid and then to perform an eigenvalues analysis that highlights how the system’s parameters affect the stability of the network. It is also shown that by means of a singular perturbation approach the resulting reduced order system well approximate the original full order system.

Mariani, Valerio; Vasca, Francesco

2014-01-01

238

Analysis and Design of Launch Vehicle Flight Control Systems  

Science.gov (United States)

This paper describes the fundamental principles of launch vehicle flight control analysis and design. In particular, the classical concept of "drift-minimum" and "load-minimum" control principles is re-examined and its performance and stability robustness with respect to modeling uncertainties and a gimbal angle constraint is discussed. It is shown that an additional feedback of angle-of-attack or lateral acceleration can significantly improve the overall performance and robustness, especially in the presence of unexpected large wind disturbance. Non-minimum-phase structural filtering of "unstably interacting" bending modes of large flexible launch vehicles is also shown to be effective and robust.

Wie, Bong; Du, Wei; Whorton, Mark

2008-01-01

239

Nonsmooth optimization analysis and algorithms with applications to optimal control  

CERN Document Server

This book is a self-contained elementary study for nonsmooth analysis and optimization, and their use in solution of nonsmooth optimal control problems. The first part of the book is concerned with nonsmooth differential calculus containing necessary tools for nonsmooth optimization. The second part is devoted to the methods of nonsmooth optimization and their development. A proximal bundle method for nonsmooth nonconvex optimization subject to nonsmooth constraints is constructed. In the last part nonsmooth optimization is applied to problems arising from optimal control of systems covered by

Makela, M M

1992-01-01

240

Operation monitoring of control engineering components by noise analysis  

International Nuclear Information System (INIS)

The results of the sensor tests regularly carried out in the Muehleberg nuclear power plant since 1994 provide a good review of the condition of the most important control components in the region of the process acquisition. With the aid of the analysis, it could be proved, among others, that plant alterations have no disadvantageous effects on the remaining measuring circuits. The trend coverage of the analysis results is a valuable aid in the ageing monitoring program. At present, investigations are in progress to discover in how far sensor tests can be extended in nuclear power plants. (author) 7 figs., 1 tab., 4 refs

 
 
 
 
241

Value-impact analysis for material control and accounting alternatives  

International Nuclear Information System (INIS)

This paper describes the results of Value-Impact analysis for the proposed material control and accounting upgrade rule for Category I fuel facilities. The analysis uses the Aggregated Systems Model (ASM), one of several assessment methodologies developed at Lawrence Livermore National Laboratory (LLNL) under the auspices of the NRC's Office of Nuclear Regulatory Research, to evaluate safeguards decisions. The evaluations are based on data gathered from representative facilities processing special nuclear material (SNM). The paper focuses on an objective of the MCandA upgrade rule of having a 90 percent probability of detecting within 24 hours any large discrepancy of SNM. 3 refs

242

Analysis of GPS Abnormal Conditions within Fault Tolerant Control Laws  

Science.gov (United States)

The Global Position System (GPS) is a critical element for the functionality of autonomous flying vehicles. The GPS operation at normal and abnormal conditions directly impacts the trajectory tracking performance of the autonomous Unmanned Aerial Vehicles (UAVs) controllers. The effects of GPS parameter variation must be well understood and user-friendly computational tools must be developed to facilitate the design and evaluation of fault tolerant control laws. This thesis presents the development of a simplified GPS error model in Matlab/Simulink and its use performing a sensitivity analysis of GPS parameters effect under system normal and abnormal operation on different UAV trajectory tracking controllers. The model statistically generates position and velocity errors, simulates the effect of GPS satellite configuration on the position and velocity measurement accuracy, and implements a set of failures to the GPS readings. The model and its graphical user interface was integrated within the WVU UAV simulation environment as a masked Simulink block. The effects on the controllers' trajectory tracking performance of the following GPS parameters were investigated within normal operation ranges and outside: time delay, update rate, error standard deviation, bias, and major position and velocity failures. Several sets of control laws with fixed and adaptive parameters and of different levels of complexity have been used in this investigation. A complex performance index formulated in terms of tracking errors and control activity was used for control laws performance evaluation. The composition of various metrics within the performance index was performed using fixed and variable weights depending on the local characteristics of the commanded trajectory. This study has revealed that GPS error parameters have a significant impact on control laws performance. The proposed GPS model has proved to be a valuable, flexible tool for testing and evaluation of the fault tolerant capabilities of autonomous flight control laws.

Al-Sinbol, Gahssan

243

Multidisciplinary Analysis of a Microsystem Device for Thermal Control  

Science.gov (United States)

A microelectromechanical (MEMS) device is under development that uses the Stirling cycle to provide cooling or heating directly to a thermally loaded surface. This MEMS cooler can be used strictly in the cooling mode, or switched between cooling and heating modes in milliseconds for precise temporal and spatial temperature control. Potential applications include cooling and thermal control of: microsystems, electronics, sensors, biomedical devices, and spacecraft components. A primary challenge for further development is the multidisciplinary analysis required to characterize and optimize its performance. This paper describes the first-order thermodynamic analysis performed on the MEMS cooler and the resulting ideal performance curves generated. The basis for additional coupled analyses such as fluid/gas dynamics, thermal, electrostatic, structural, dynamic, material, and processing is addressed. Scaling issues relevant to the device and the breakdown of continuum theory in the micro-domain is also examined.

Moran, Matthew E.

2002-07-01

244

THE ACCESS CONTROL SYSTEM BASED ON LINEAR DISCRIMINANT ANALYSIS  

Directory of Open Access Journals (Sweden)

Full Text Available Face recognition represents an important computer vision domain that has been researched in the last decades. The objective of this research is to develop an Access Control System based on Face Recognition using Linear Discriminant Analysis (LDA method. The analysis is done by making an application of face recognition using LDA for extracting features of the face and the output for controlling relay as a simulation of a door using AVR Microcontroller. The result achieved by the application is a face recognition system using LDA can obtain excellent result that is 95% success rate in face recognition with the image of a face that was tested by 40 people, instead of the previously popular feature extraction methods such as PCA. Based on the experimental results, attendance system based on face recognition using LDA obtain better result compared with PCA based face recognition.

Widodo Budiharto

2014-01-01

245

Pressure Control in Distillation Columns: A Model-Based Analysis  

DEFF Research Database (Denmark)

A comprehensive assessment of pressure control in distillation columns is presented, including the consequences for composition control and energy consumption. Two types of representative control structures are modeled, analyzed, and benchmarked. A detailed simulation test, based on a real industrial distillation column, is used to assess the differences between the two control structures and to demonstrate the benefits of pressure control in the operation. In the second part of the article, a thermodynamic analysis is carried out to establish the influence of pressure on relative volatility for (pseudo)binary mixtures. A simple criterion is found, based on the difference in the scaled heats of vaporization of the light and heavy compounds: A large difference indicates that relative volatility is sensitive to pressure changes, whereas no a priori conclusion can be made for small differences. Depending on the sensitivity of relative volatility to pressure, it is shown that controlling the bottom-tray pressure instead of the top-tray pressure leads to operation at the minimum possible average column pressure, so that significant energy savings can be achieved.

Mauricio Iglesias, Miguel; Bisgaard, Thomas

2014-01-01

246

Control Flow Analysis Can Find New Flaws Too  

DEFF Research Database (Denmark)

A previous study showed how control flow analysis can be applied to analyse key distribution protocols based on symmetric key cryptography. We have extended both the theoretical treatment and our fully automatic verifier to deal with protocols based on asymmetric cryptography. This paper reports on the application of our technique - exemplified on the Beller-Chang-Yacobi MSR protocol, which uses both symmetric and asymmetric cryptography - and show how we discover an undocumented flaw.

Buchholtz, Mikael; Nielson, Flemming

2004-01-01

247

Analysis of factors influencing local control of medulloblastoma  

International Nuclear Information System (INIS)

To examine the influence of various prognostic factors on local control of medulloblastoma. Sixty-five patients who had been treated between 1980 and 1990 at our six hospitals were retrospectively studied. Factors included in the Cox's multivariate analysis were sex, age (log(y.o.+1)), performance status, pretreatment T-stage (judged from the findings of CT and/or MRI; T1: 3 patients, T2: 17, T3 (with hydrocephalus): 44, T4: 1), extent of surgical resection (total: 30 patients, less than total: 35), total dose (21-87 Gy, median: 55) and overall treatment time (19-163 days, median: 54) of local irradiation, and use of adjuvant chemotherapy or immunotherapy. Recurrence occurred in one T2 patient and in 17 T3 patients. The multivariate analysis showed that local tumor control decreased with advance in T-stage (p=0.04) and with prolonged overall treatment times (p=0.003), and that it increased with higher total doses (p=0.01). When analysis was limited to T3 patients, usefulness of the chemotherapy was also suggested (p=0.03). However, the influence of the extent of resection on local tumor control was not statistically significant because resectability depended on T-stage. This analysis showed that local control of medulloblastoma was influenced by pretreatment T-stage, total dose and overall irradiation treatment time, and probably by the adjuvant chemotherapy used. Some of the observed losses by prolongations in radiotherapy may reflect proliferation of tumor cells dury reflect proliferation of tumor cells during radiotherapy. (author)

248

Intelligent Control in Automation Based on Wireless Traffic Analysis  

Energy Technology Data Exchange (ETDEWEB)

Wireless technology is a central component of many factory automation infrastructures in both the commercial and government sectors, providing connectivity among various components in industrial realms (distributed sensors, machines, mobile process controllers). However wireless technologies provide more threats to computer security than wired environments. The advantageous features of Bluetooth technology resulted in Bluetooth units shipments climbing to five million per week at the end of 2005 [1, 2]. This is why the real-time interpretation and understanding of Bluetooth traffic behavior is critical in both maintaining the integrity of computer systems and increasing the efficient use of this technology in control type applications. Although neuro-fuzzy approaches have been applied to wireless 802.11 behavior analysis in the past, a significantly different Bluetooth protocol framework has not been extensively explored using this technology. This paper presents a new neurofuzzy traffic analysis algorithm of this still new territory of Bluetooth traffic. Further enhancements of this algorithm are presented along with the comparison against the traditional, numerical approach. Through test examples, interesting Bluetooth traffic behavior characteristics were captured, and the comparative elegance of this computationally inexpensive approach was demonstrated. This analysis can be used to provide directions for future development and use of this prevailing technology in various control type applications, as well as making the use of it more secure.

Kurt Derr; Milos Manic

2007-08-01

249

Intelligent Control in Automation Based on Wireless Traffic Analysis  

Energy Technology Data Exchange (ETDEWEB)

Wireless technology is a central component of many factory automation infrastructures in both the commercial and government sectors, providing connectivity among various components in industrial realms (distributed sensors, machines, mobile process controllers). However wireless technologies provide more threats to computer security than wired environments. The advantageous features of Bluetooth technology resulted in Bluetooth units shipments climbing to five million per week at the end of 2005 [1, 2]. This is why the real-time interpretation and understanding of Bluetooth traffic behavior is critical in both maintaining the integrity of computer systems and increasing the efficient use of this technology in control type applications. Although neuro-fuzzy approaches have been applied to wireless 802.11 behavior analysis in the past, a significantly different Bluetooth protocol framework has not been extensively explored using this technology. This paper presents a new neurofuzzy traffic analysis algorithm of this still new territory of Bluetooth traffic. Further enhancements of this algorithm are presented along with the comparison against the traditional, numerical approach. Through test examples, interesting Bluetooth traffic behavior characteristics were captured, and the comparative elegance of this computationally inexpensive approach was demonstrated. This analysis can be used to provide directions for future development and use of this prevailing technology in various control type applications, as well as making the use of it more secure.

Kurt Derr; Milos Manic

2007-09-01

250

An Unified Approach for Process Quality Analysis and Control  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract— The process in a company finally results in product of the company, which represents the company standard. Hence, during the process execution time quality of the process needs to be taken care before and after the work done. In this paper, an unified approach to quality analysis and control of a process development is presented. This approach gives an overview of what the task the company assigned to the employers. The process is defined as the set of action items to achieve the work completion. Quality means grade of excellence. Quality analysis of a process is an improvement of the process and making sure that all the standard procedures are followed. An unified approach designed in this paper is a combination of software cost estimation and a financial market forecasting with the support of historical data, statistical data mining technique and artificial neural networks, which helps the developers as well as investors in strategic planning and investment decision making. Therefore, the paper describes a recommended process to develop software (SW cost estimates for software managers, perform financial market forecasting to control quality of process development. As a result, the improvement and analysis of the process quality can be performed from basic level to the corporate level. By this work, we conclude that the process quality control can be made easier and efficient compared to the old graphical analytics technique.

Prof.Chandrakanth Biradar,Aruna Kawdi

2012-09-01

251

SEM Image Analysis for Quality Control of Nanoparticles  

Science.gov (United States)

In nano-medicine, mesoporous silicon particles provide efficient vehicles for the dissemination and delivery of key proteins at the micron scale. We propose a new quality-control method for the nanopore structure of these particles, based on image analysis software developed to automatically inspect scanning electronic microscopy (SEM) images of nanoparticles in a fully automated fashion. Our algorithm first identifies the precise position and shape of each nanopore, then generates a graphic display of these nanopores and of their boundaries. This is essentially a texture segmentation task, and a key quality-control requirement is fast computing speed. Our software then computes key shape characteristics of individual nanopores, such as area, outer diameter, eccentricity, etc., and then generates means, standard deviations, and histograms of each pore-shape feature. Thus, the image analysis algorithms automatically produce a vector from each image which contains relevant nanoparticle quality control characteristics, either for comparison to pre-established acceptability thresholds, or for the analysis of homogeneity and the detection of outliers among families of nanoparticles.

Alexander, S. K.; Azencott, R.; Bodmann, B. G.; Bouamrani, A.; Chiappini, C.; Ferrari, M.; Liu, X.; Tasciotti, E.

252

Detrended fluctuation analysis of a systolic blood pressure control loop  

Energy Technology Data Exchange (ETDEWEB)

We use detrended fluctuation analysis (DFA) to study the dynamics of blood pressure oscillations and its feedback control in rats by analyzing systolic pressure time series before and after a surgical procedure that interrupts its control loop. We found, for each situation, a crossover between two scaling regions characterized by exponents that reflect the nature of the feedback control and its range of operation. In addition, we found evidence of adaptation in the dynamics of blood pressure regulation a few days after surgical disruption of its main feedback circuit. Based on the paradigm of antagonistic, bipartite (vagal and sympathetic) action of the central nerve system, we propose a simple model for pressure homeostasis as the balance between two nonlinear opposing forces, successfully reproducing the crossover observed in the DFA of actual pressure signals.

Galhardo, C E C; Penna, T J P; Argollo de Menezes, M [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea, s/n, 24210-340, Niteroi, RJ (Brazil); Soares, P P S [Instituto Biomedico, Universidade Federal Fluminense, R. Prof. Hernani Melo n. 101, 24210-130, Niteroi, RJ (Brazil)], E-mail: marcio@mail.if.uff.br

2009-10-15

253

Detrended fluctuation analysis of a systolic blood pressure control loop  

International Nuclear Information System (INIS)

We use detrended fluctuation analysis (DFA) to study the dynamics of blood pressure oscillations and its feedback control in rats by analyzing systolic pressure time series before and after a surgical procedure that interrupts its control loop. We found, for each situation, a crossover between two scaling regions characterized by exponents that reflect the nature of the feedback control and its range of operation. In addition, we found evidence of adaptation in the dynamics of blood pressure regulation a few days after surgical disruption of its main feedback circuit. Based on the paradigm of antagonistic, bipartite (vagal and sympathetic) action of the central nerve system, we propose a simple model for pressure homeostasis as the balance between two nonlinear opposing forces, successfully reproducing the crossover observed in the DFA of actual pressure signals.

254

Survey on Challenges in Analysis Research of Networked Control Systems  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, the past and current issues involved in the design of decentralized networked control systems (NCSs are reviewed. The NCSs has got deeply into all aspects of modern society, especially in control system, the NCSs can reduce system cost and size, minish design difficulty, and increase flexibility of system. The main research works are focused on time-delay, packet dropouts, quantization and schedule which are included in the time-driven design of LTI control system with network. The stability and performance of such system is analysis. The overview is concentrated on some fundamental problems of the NCSs in the previous research work, on the basis of a brief review of representative research, summaries a number of problems and solutions faced of the NCSs, the future directions in NCSs are pointed out.

Yiwei Feng

2013-02-01

255

System integration and control strategy analysis of PEMFC car  

International Nuclear Information System (INIS)

A new fuel car was designed according to the prototype LN2000 hydrogen-oxygen fuel cell car. The new prototype consists of a compact fuel cell engine with separated fuel cell stack, nickel metal hydride battery, a motor with power of 30Kw/100Kw and an inverter with high efficiency. With in the powertrain, a two-shift Planet gear transmission was employed. The power performance was greatly improved. New battery with EMS, new self-developed fuel cell engine, the motor propulsion system and electronic controlled transmission make it feasible to control the whole fuel car automatically and efficiently with optimization. The presents the system integration and the control strategy analysis of the fuel cell car prototype. The paper can be used for reference for engineers in the field of fuel cell vehicle. (author)

256

Detrended Fluctuation Analysis of Systolic Blood Pressure Control Loop  

CERN Document Server

We use detrended fluctuation analysis (DFA) to study the dynamics of blood pressure oscillations and its feedback control in rats by analyzing systolic pressure time series before and after a surgical procedure that interrupts its control loop. We found, for each situation, a crossover between two scaling regions characterized by exponents that reflect the nature of the feedback control and its range of operation. In addition, we found evidences of adaptation in the dynamics of blood pressure regulation a few days after surgical disruption of its main feedback circuit. Based on the paradigm of antagonistic, bipartite (vagal and sympathetic) action of the central nerve system, we propose a simple model for pressure homeostasis as the balance between two nonlinear opposing forces, successfully reproducing the crossover observed in the DFA of actual pressure signals.

Galhardo, C E C; de Menezes, M Argollo; Soares, P P S

2009-01-01

257

Robust Stability Analysis with Time Delay Using PI Controller  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, real time implementation of PI and PID controllers is Investigated for stabilizing an arbitrary-order plant or system. Simple closed loop feedback ,PI controller can overcome all the problems of uncertainties like time delay in LTI (Linear Time Invariant system.This paper will give us an implortant alogorithm to be imlemented in MATLAB for achieving the robust stability in LTI plant in presence of any type of perturbations or external disturbances. In this paper, a single input and single output (LTI linear time invariant plant under perturbed conditions with additive uncertainity weight senstivity is considered. In this paper especially, I have found all set of PI gains Kp,Ki which will promise us for the stability in a given disturbed (SISO (LTI system by achieving the robust stability constraint ? <=1 can be found by obtaining the PI controller gains Kp,Ki using frequency domain analysis .

Gursewak Singh

2012-11-01

258

Experimental Bifurcation Analysis Using Control-Based Continuation  

DEFF Research Database (Denmark)

The focus of this thesis is developing and implementing techniques for performing experimental bifurcation analysis on nonlinear mechanical systems. The research centers around the newly developed control-based continuation method, which allows to systematically track branches of stable and unstable equilibria under variation of parameters. As a test case we demonstrate that it is possible to track the complete frequency response, including the unstable branches, for a harmonically forced impact oscillator with hardening spring nonlinearity, controlled by electromagnetic actuators. The method requires the constitution of a non-invasive and locally stabilizing control scheme, which must be tuned without a-priori study of a model. We propose a sequence of experiments that allows to choose optimal control-gains, filter parameters and settings for a continuation method. This experimental tuning procedure is applied to our test rig, resulting in a reliable non-invasive, locally stabilizing control. The use of stabilizing control makes it difficult to determine the stability of the underlying uncontrolled equilibrium. Based on the idea of momentarily modifying or disabling the control and study the resulting behavior, we propose and test three different methods for assessing stability of equilibrium states during experimental continuation. We show that it is possible to determine the stability without allowing unbounded divergence, and that it is under certain circumstances possible to quantify instability in terms of finite-time Lyapunov exponents. A software toolbox for the Matlab continuation platform COCO has been developed and will be made freely available. This toolbox implements functions necessary for interfacing a numerical continuation code with a real experiment, as well as provide means for simulating control-based continuation experiments. Finally, the feasibility of implementing the method for rotating machinery is discussed.

Bureau, Emil

2014-01-01

259

Phase formation in the systems Ag2MoO4-MO-MoO3 (M=Ca, Sr, Ba, Pb, Cd, Ni, Co, Mn) and crystal structures of Ag2M2(MoO4)3 (M=Co, Mn)  

International Nuclear Information System (INIS)

Phase equilibria in the systems Ag2MoO4-MMoO4 (M=Ca, Sr, Ba, Pb, Ni, Co, Mn) and subsolidus phase relations in the systems Ag2MoO4-MO-MoO3 (M=Ca, Pb, Cd, Mn, Co, Ni) were investigated using XRD and thermal analysis. The systems Ag2MoO4-MMoO4 (M=Ca, Sr, Ba, Pb, Ni) belong to the simple eutectic type whereas in the systems Ag2MoO4-MMoO4 (M=Co, Mn) incongruently melting Ag2M2(MoO4)3 (M=Co, Mn) were formed. In the ternary oxide systems studied no other compounds were found. Low-temperature LT-Ag2Mn2(MoO4)3 reversibly converts into the high-temperature form of a similar structure at 450-500 deg. C. The single crystals of Ag2Co2(MoO4)3 and LT-Ag2Mn2(MoO4)3 were grown and their structures determined (space group P1-bar, Z=2; lattice parameters are a=6.989(1) A, b=8.738(2) A, c=10.295(2) A, ?=107.67(2) deg., ?=105.28(2) deg., ?=103.87(2) deg. and a=7.093(1) A, b=8.878(2) A, c=10.415(2) A, ?=106.86(2) deg., ?=105.84(2) deg., ?=103.77(2) deg, respectively) and refined to R(F)=0.0313 and 0.0368, respectively. The both compounds are isotypical to Ag2Zn2(MoO4)3 and contain mixed frameworks of MoO4 tetrahedra and pairs oO4 tetrahedra and pairs of M2+O6 octahedra sharing common edges. The Ag+ ions are disordered and located in the voids forming infinite channels running along the a direction. The peculiarities of the silver disorder in the structures of Ag2M2(MoO4)3 (M=Zn, Mg, Co, Mn) are discussed as well as their relations with analogous sodium-containing compounds of the structural family of Na2Mg5(MoO4)6. The phase transitions in Ag2M2(MoO4)3 (M=Mg, Mn) of distortive or order-disorder type are suggested to have superionic character

260

Contribution to stability analysis of nonlinear control systems  

Directory of Open Access Journals (Sweden)

Full Text Available The Popov criterion for the stability of nonlinear control systems is considered. The Popov criterion gives sufficient conditions for stability of nonlinear systems in the frequency domain. It has a direct graphical interpretation and is convenient for both design and analysis. In the article presented, a table of transfer functions of linear parts of nonlinear systems is constructed. The table includes frequency response functions and offers solutions to the stability of the given systems. The table makes a direct stability analysis of selected nonlinear systems possible. The stability analysis is solved analytically and graphically.Then it is easy to find out if the nonlinear system is or is not stable; the task that usually ranks among the difficult task in engineering practice.

?varc Ivan

2003-12-01

 
 
 
 
261

Peculiarities of cascade photon emission and energy storage in M{sub 1-x}Pr{sub x}F{sub 2+x} (M=Ca, Sr, Ba, x{approx}0.35) crystals  

Energy Technology Data Exchange (ETDEWEB)

Peculiarities of cascade photon emission (CPE) and energy storage in M{sub 1-x}Pr{sub x}F{sub 2+x} (M=Ca, Sr, Ba, x{approx}0.35) crystals were studied. The investigation of lattice parameters revealed that these solid solutions belong to the fluorite structure type with the lattice constant noticeably different from that of MF{sub 2} crystals. Absorption, emission and excitation spectra of M{sub 0.65}Pr{sub 0.35}F{sub 2.35} were measured at LHeT and RT. As it turned out the typical for 4f{sup 2{yields}}4f{sup 2} transition in Pr{sup 3+} emission lines are broadened as compared with the PrF{sub 3} crystal. The analysis of the excitation spectra broadening does not allow bringing out the type of the superlattice, which is inherent to the material, but it indicates clearly the simultaneous presence of different types of the Pr centers in mixed crystals. Yet another specific feature is the higher radiation sensitivity of these fluorides relatively PrF{sub 3}, MF{sub 2} and Pr-doped MF{sub 2} crystals. Coloration efficiency enhances in direction Ca{yields}Sr{yields}Ba, and the positions of induced absorption band depend on composition of the solid solution. Colorization, thermo-stimulated luminescence and afterglow of the M{sub 1-x}Pr{sub x}F{sub 2+x} crystals denote high radiation sensitivity as compared with M{sub 1-x}Ce{sub x}F{sub 2+x}.

Shiran, N., E-mail: shiran@isc.kharkov.co [Institute for Scintillation Materials NAS of Ukraine, 60 Lenin Avenue, 61001 Kharkov (Ukraine); Gektin, A.; Nesterkina, V.; Boyarintseva, Y.; Baumer, V. [Institute for Scintillation Materials NAS of Ukraine, 60 Lenin Avenue, 61001 Kharkov (Ukraine); Stryganyuk, G.; Voloshinovskii, A. [Ivan Franko National University of Lviv, 8 Kyryla i Mefodiya Street, 79005 Lviv (Ukraine); Shimamura, K.; Villora, E. [National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2010-12-15

262

Transient analysis of energy Transfer Control (ECT) and compressor bleed concepts of remote lift fan control  

Science.gov (United States)

The transient performance of two concepts for control of vertical takeoff aircraft remote lift fans is analyzed and discussed. Both concepts employ flow transfer between pairs of lift fans located in separate parts of the aircraft in order to obtain attitude control moments for hover and low-speed flight. The results presented are from a digital computer, dynamic analysis of the YJ97/LF460 remote drive turbofan. The transient responses of the two systems are presented for step demands in lift and moment.

Sellers, J. F.

1973-01-01

263

Multi-component controllers in reactor physics optimality analysis  

International Nuclear Information System (INIS)

An algorithm is developed for the optimality analysis of thermal reactor assemblies with multi-component control vectors. The neutronics of the system under consideration is assumed to be described by the two-group diffusion equations and constraints are imposed upon the state and control variables. It is shown that if the problem is such that the differential and algebraic equations describing the system can be cast into a linear form via a change of variables, the optimal control components are piecewise constant functions and the global optimal controller can be determined by investigating the properties of the influence functions. Two specific problems are solved utilizing this approach. A thermal reactor consisting of fuel, burnable poison and moderator is found to yield maximal power when the assembly consists of two poison zones and the power density is constant throughout the assembly. It is shown that certain variational relations have to be considered to maintain the activeness of the system equations as differential constraints. The problem of determining the maximum initial breeding ratio for a thermal reactor is solved by treating the fertile and fissile material absorption densities as controllers. The optimal core configurations are found to consist of three fuel zones for a bare assembly and two fuel zones for a reflected assembly. The optimum fissile material density is determined to be inversely proportional to the thermal fluxto the thermal flux

264

Reduced order modeling, nonlinear analysis and control methods for flow control problems  

Science.gov (United States)

Flow control refers to the ability to manipulate fluid flow so as to achieve a desired change in its behavior, which offers many potential technological benefits, such as reducing fuel costs for vehicles and improving effectiveness of industrial processes. An interesting case of flow control is cavity flow control, which has been the motivation of this study: When air flow passes over a shallow cavity a strong resonance is produced by a natural feedback mechanism, scattering acoustic waves that propagate upstream and reach the shear layer, and developing flow structures. These cause many practical problems including damage and fatigue in landing gears and weapons bays in aircrafts. Presently there is a lack of sufficient mathematical analysis and control design tools for flow control problems. This includes mathematical models that are amenable to control design. Recently reduced-order modeling techniques, such as those based on proper orthogonal decomposition (POD) and Galerkin projection (GP), have come to interest. However, a main issue with these models is that the effect of boundary conditions, which is where the control input is, gets embedded into system coefficients. This results in a form quite different from what one deals with in standard control systems framework, which is a set of ordinary differential equations (ODE) where the input appears as an explicit term. Another issue with the standard POD/GP models is that they do not yield to systems that have any apparent structure in their coefficients. This leaves one with little choice other than to neglect the nonlinearities of the models and employ standard linear control theory based designs. The research presented in this thesis makes an effort at closing the gaps mentioned above by (1) presenting a reduced-order modeling method utilizing a novel technique for input separation on POD/GP models, (2) introducing a technique based on averaging theory and center manifold theory so as to reveal certain structures embedded in the model, and (3) developing nonlinear analysis and control design approaches for the resulting model. The theory is complemented by examples and case studies as appropriate, including the case of cavity flow control.

Kasnakoglu, Cosku

265

End-tidal versus manually-controlled low-flow anaesthesia.  

Science.gov (United States)

During low-flow manually-controlled anaesthesia (MCA) the anaesthetist needs constantly adjust end-tidal oxygen (EtO2) and anaesthetic concentrations (EtAA) to assure an adequate and safe anaesthesia. Recently introduced anaesthetic machines can automatically maintain those variables at target values, avoiding the burden on the anaesthetist. End-tidal-controlled anaesthesia (EtCA) and MCA provided by the same anaesthetic machine under the same fresh gas flow were compared. Eighty patients were prospectively observed: in MCA group (n = 40) target end-tidal sevoflurane (1%) and EtO2 concentrations (? 35%) were manually controlled by the anaesthetist. In EtCA group (n = 40) the same anaesthetic machine with an additional end-tidal control feature was used to reach the same targets, rendering automatic the achievement and maintenance of those targets. Anaesthetic machine characteristics, amount of consumed gases, oxygen and sevoflurane efficiencies, and the amount of interventions by the anaesthetist were recorded. In EtCA group EtAA was achieved later (145 s) than in MCA (71 s) and remained controlled thereafter. Even though the target expired gas fractions were achieved faster in MCA, manual adjustments were required throughout anaesthesia for both oxygen and sevoflurane. In MCA patients the number of manual adjustments to stabilize EtAA and EtO2 were 137 and 107, respectively; no adjustment was required in EtCA. Low-flow anaesthesia delivered with an anaesthetic machine able to automatically control EtAA and EtO2 provided the same clinical stability and avoided the continuous manual adjustment of delivered sevoflurane and oxygen concentrations. Hence, the anaesthetist could dedicate more time to the patient and operating room activities. PMID:24114079

Lucangelo, Umberto; Garufi, Giuliana; Marras, Emanuele; Ferluga, Massimo; Turchet, Federica; Bernabè, Francesca; Comuzzi, Lucia; Berlot, Giorgio; Zin, Walter A

2014-04-01

266

Fault-tolerant Supervisory Control : System Analysis and Logic Design  

DEFF Research Database (Denmark)

The main purpose of this work has been to achieve active fault-tolerance in control systems, defined as a methodology where fault detection and isolation techniques are combined with supervisory control to achieve autonomous accommodation of faults before they develop into failures. The aim of this work has been to develop and employ concepts and methods that are suitable for use in different automation processes, with applicability in various industrial fields. The requirements for high productivity and quality has resulted in employing additional instrumentation and use of more sophisticated control algorithms. The drawback is, however, that these control systems have become more vulnerable to even simple faults in instrumentation. On the other hand, due to cost-optimality requirements, an extensive use of hardware redundancy has been prohibited. Nevertheless, the dependency and availability could be increased through enhancing control systems' ability to on-line perform fault detection and reconfiguration when a fault occurs and before a safety system shuts-down the entire process. The main contributions of this research effort are development and experimentation with methodologies for systematic analysis of reconfiguration and design of supervisor logic. In addition, useful experience is obtained through implementation of a fault-tolerant control scheme against a simulated ship and its propulsion system. A development methodology, which was suggested in the Control Engineering Department, is extended to cope with the important reconfiguration problem. In order to enable a designer to acquire knowledge about reconfiguration possibilities, the structural analysis method is added as an extension to the existing methodology. This extension builds upon the earlier method where fault propagation and severity analysis are the essential parts. Structural analysis (SA) enables the designer to distinguish between the parts of the systems with no redundant information and the parts with possible redundant information. This method, hence, provides the designer with information, which is necessary during the selection of remedial actions. Furthermore, it is shown how sensor information fusion is obtained by using the SA method. The construction of the supervisor's decision logic is essential for the active form of fault-tolerant control. In this regard, two approaches has been presented. The first aims at constructing the decision logic in form of a ``language''. This language is obtained as a direct result of the component based approach, presented in this thesis. This approach is based on the definition of a functional component, components placement in a control system hierarchy and the definition of system level hierarchy. The supervisor language includes all valid strings, representing the combination of valid components, that keep the system functional. This approach is simple and can be automated. In the second approach, implementation of supervisor functionality is realized on the basis of an extension to the traditional state-event machines. Due to parallelity (inherent modularity) the supervisor logic is more easily modified, updated, maintained, and tested. A salient feature is that a change in one task only necessitates redesign of essentially one corresponding state-event machine (SEM). A heuristic guideline is provided for designing the logic in form of SEMs. A ship propulsion system benchmark has been designed and used as a case study. This includes experimentation with the above methodologies and implementation of a fault-tolerant control against the simulation. Four generic faults have been considered. It has been shown how the SA method is easily employed to generate analytical redundancy relations, which in turn are then used for FDI purposes. Three different methods are used to generate residuals. These methods are: simple numerical calculation, a non-linear observer, and a Neuro-Fuzzy method. Employment of each method follows the assumption about the available system information. The results show that it is p

Izadi-Zamanabadi, Roozbeh

1999-01-01

267

Component-based analysis of embedded control applications  

DEFF Research Database (Denmark)

The widespread use of embedded systems requires the creation of industrial software technology that will make it possible to engineer systems being correct by construction. That can be achieved through the use of validated (trusted) components, verification of design models, and automatic configuration of applications from validated design models and trusted components. This design philosophy has been instrumental for developing COMDES—a component-based framework for distributed embedded control systems. A COMDES application is conceived as a network of embedded actors that are configured from instances of reusable, executable components—function blocks (FBs). System actors operate in accordance with a timed multitasking model of computation, whereby I/O signals are exchanged with the controlled plant at precisely specified time instants, resulting in the elimination of I/O jitter. The paper presents an analysis technique that can be used to validate COMDES design models in SIMULINK. It is based on a transformation of the COMDES design model into a SIMULINK analysis model, which preserves the functional and timing behaviour of the application. This technique has been employed to develop a feasible (light-weight) analysis method based on runtime observers. The latter are conceived as special-purpose actors running in parallel with the application actors, while checking system properties specified in Linear Temporal Logic. Observers are configured from reusable FBs that can be exported to SIMULINK in the same way as application components, making it possible to analyze system properties via simulation. The discussion is illustrated with an industrial case study—a Medical Ventilator Control System, which has been used to validate the developed design and analysis methods.

Angelov, Christo K.; Guan, Wei

2011-01-01

268

Stability analysis and controller synthesis for hybrid dynamical systems.  

Science.gov (United States)

Wherever continuous and discrete dynamics interact, hybrid systems arise. This is especially the case in many technological systems in which logic decision-making and embedded control actions are combined with continuous physical processes. Also for many mechanical, biological, electrical and economical systems the use of hybrid models is essential to adequately describe their behaviour. To capture the evolution of these systems, mathematical models are needed that combine in one way or another the dynamics of the continuous parts of the system with the dynamics of the logic and discrete parts. These mathematical models come in all kinds of variations, but basically consist of some form of differential or difference equations on the one hand and automata or other discrete-event models on the other hand. The collection of analysis and synthesis techniques based on these models forms the research area of hybrid systems theory, which plays an important role in the multi-disciplinary design of many technological systems that surround us. This paper presents an overview from the perspective of the control community on modelling, analysis and control design for hybrid dynamical systems and surveys the major research lines in this appealing and lively research area. PMID:20921005

Heemels, W P M H; De Schutter, B; Lunze, J; Lazar, M

2010-11-13

269

Control, data acquisition, data analysis and remote participation in LHD  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the control, data acquisition, data analysis and remote participation facilities of the Large Helical Device (LHD), which is designed to confine the plasma in steady state. In LHD the plasma duration exceeds 3000 s by controlling the plasma position, the density and the ICRF heating. The 'LABCOM' data acquisition system takes both the short-pulse and the steady-state data. A two-layer Mass Storage System with RAIDs and Blu-ray Disk jukeboxes in a storage area network has been developed to increase capacity of storage. The steady-state data can be monitored with a Web browser in real time. A high-level data analysis system with Web interfaces is being developed in order to provide easier usage of LHD data and large FORTRAN codes in a supercomputer. A virtual laboratory system for the Japanese fusion community has been developed with Multi-protocol Label Switching Virtual Private Network Technology. Collaborators at remote sites can join the LHD experiment or use the NIFS supercomputer system as if they were working in the LHD control room.

Nagayama, Y. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan)], E-mail: nagayama.yoshio@nifs.ac.jp; Emoto, M. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Nakanishi, H. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Sudo, S. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Imazu, S. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Inagaki, S. [RIAM, Kyushu University, Kasuga 816-8580 (Japan); Iwata, C.; Kojima, M.; Nonomura, M.; Ohsuna, M.; Tsuda, K.; Yoshida, M.; Chikaraishi, H.; Funaba, H.; Horiuchi, R.; Ishiguro, S.; Ito, Y.; Kubo, S. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Mase, A. [KASTEC, Kyushu University, Kasuga 816-8580 (Japan); Mito, T. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan)] (and others)

2008-04-15

270

Control assembly ejection accident analysis for WWER-440 (Armenian NPP)  

International Nuclear Information System (INIS)

Control Assembly ejection in WWER-440 initiated by the loss of integrity of the Control Assemblies drive housing has been analyzed. This event causes a very rapid reactivity insertion to the core and small break LOCA which potentially could lead to rapid power increase and redistribution of heat release in the core resulting in a fuel, cladding and coolant temperature rise; primary pressure increase, radiological consequences due to loss of primary coolant and potential loss of cladding integrity and fuel disintegration (if applicable). Methodology of the analysis is based on conservative assumptions as well as on deterministic approach for selection of functioning logic of systems and equipment's to maximize reactor core power and minimize power decreasing reactivity feedback. Computational analyses were performed by 3D kinetics PARCS-RELAP coupled code. WWER-440 fuel cross-section libraries, diffusion coefficients and kinetics parameters were calculated by HELOS code. In this paper analysis of accident for Hot Full Power was presented. Results of analysis show that ANPP WWER-440 reactor design meets acceptance criteria prescribed for RIA type design based accidents (Authors)

271

Assessment of quality control approaches for metagenomic data analysis  

Science.gov (United States)

Currently there is an explosive increase of the next-generation sequencing (NGS) projects and related datasets, which have to be processed by Quality Control (QC) procedures before they could be utilized for omics analysis. QC procedure usually includes identification and filtration of sequencing artifacts such as low-quality reads and contaminating reads, which would significantly affect and sometimes mislead downstream analysis. Quality control of NGS data for microbial communities is especially challenging. In this work, we have evaluated and compared the performance and effects of various QC pipelines on different types of metagenomic NGS data and from different angles, based on which general principles of using QC pipelines were proposed. Results based on both simulated and real metagenomic datasets have shown that: firstly, QC-Chain is superior in its ability for contamination identification for metagenomic NGS datasets with different complexities with high sensitivity and specificity. Secondly, the high performance computing engine enabled QC-Chain to achieve a significant reduction in processing time compared to other pipelines based on serial computing. Thirdly, QC-Chain could outperform other tools in benefiting downstream metagenomic data analysis. PMID:25376098

Zhou, Qian; Ning, Kang

2014-01-01

272

Assessment of quality control approaches for metagenomic data analysis.  

Science.gov (United States)

Currently there is an explosive increase of the next-generation sequencing (NGS) projects and related datasets, which have to be processed by Quality Control (QC) procedures before they could be utilized for omics analysis. QC procedure usually includes identification and filtration of sequencing artifacts such as low-quality reads and contaminating reads, which would significantly affect and sometimes mislead downstream analysis. Quality control of NGS data for microbial communities is especially challenging. In this work, we have evaluated and compared the performance and effects of various QC pipelines on different types of metagenomic NGS data and from different angles, based on which general principles of using QC pipelines were proposed. Results based on both simulated and real metagenomic datasets have shown that: firstly, QC-Chain is superior in its ability for contamination identification for metagenomic NGS datasets with different complexities with high sensitivity and specificity. Secondly, the high performance computing engine enabled QC-Chain to achieve a significant reduction in processing time compared to other pipelines based on serial computing. Thirdly, QC-Chain could outperform other tools in benefiting downstream metagenomic data analysis. PMID:25376098

Zhou, Qian; Su, Xiaoquan; Ning, Kang

2014-01-01

273

Multi-dimensional project evaluation: Combining cost-benefit analysis and multi-criteria analysis with the COSIMA software system  

DEFF Research Database (Denmark)

This paper proposes a methodology that integrates quantitative and qualitative assessment. The methodology proposed combines conventional cost-benefit analysis (CBA) with multi-criteria analysis (MCA). The CBA methodology, based on welfare theory, assures that the project with the highest welfare for society is ranked uppermost. To compare the different impacts, it is necessary to have a common monetary unit. Theoretically, all benefits and all costs should be accounted for in socio-economic cost-benefit analysis. However, this is far from in practical the general case due to difficulties in a valuating all the criteria in monetary terms. Thus CBA does not meet the need for a comprehensive evaluation, for which reason MCA is introduced to overcome this problem. Not only does MCA provides an opportunity to include non-market impacts in the analysis, but MCA also provides a framework for breaking down a problem into its constituent parts in order to better understand the problem and consequently arrive at a decision. However, while MCA opens up for the possibility to include non-market impacts, it does not provide the decision makers with guidance combining the CBA with MCA. In the paper different methods for combining cost-benefit analysis and multi-criteria analysis are examined and compared and a software system is presented. The software system gives the decision makers some possibilities regarding preference analysis, sensitivity and risk analysis. The aim of the software is to facilitate a straightforward method to support decision making involving both quantitative and qualitative impacts. An outcome of this is that the methodology and the results on this basis are easily understood by the different stakeholders, which is seen as important. The methodology and software system are demonstrated by examining the decision problem of choosing between alternatives for a new airport to service the capital of Greenland, Nuuk. Three different alternatives are examined ranging in costs from 90m USD to 400m USD. Furthermore, three sets of different stakeholders’ preferences (decision makers, citizens in Nuuk and other citizens in Greenland) are examined and compared. The cost-benefit analysis of the three airport alternatives includes impacts like travel time (for business and local travellers), waiting time, drawback of shifts, regularity, out of pocket costs, operating costs and not the least construction and maintenance costs. The MCA is made use of to assess noise, land use planning, business potential and tourism impacts for the three alternatives. More technically the software system offers a set of different features to undertake the MCA. Thus the users have two different methods to assess weights for the criteria, either by using the Swing Weight method or the more simple Rank Order Distribution (ROD) method. For evaluating the different alternatives with respect to each criterion the user has the possibility of making use of the Analytical Hierarchy Process (AHP), REMBRANDT or Simple Multiple-Attribute Rating Technique Exploiting Ranks (SMARTER) methods. Finally, a feature combining the CBA and MCA results can be provided by applying a trade off between the two methods or by means of the so called efficiency frontier is demonstrated. The presented multi-dimensional methodology and software system for CBA and MCA decision making is finally compared with other methods for combining the CBA and MCA. Ultimately, some conclusions are made and perspectives are drawn. Keywords: Cost-benefit analysis, Multi-criteria analysis, Multiple Criteria Decision Aiding, Transport infrastructure, Analytical Hierarchy Process, REMBRANDT, SMARTER, stakeholders’ preferences and CBA&MCA Software system.

274

Discomfort Analysis in Computerized Numeric Control Machine Operations  

Science.gov (United States)

Objectives The introduction of computerized numeric control (CNC) technology in manufacturing industries has revolutionized the production process, but there are some health and safety problems associated with these machines. The present study aimed to investigate the extent of postural discomfort in CNC machine operators, and the relationship of this discomfort to the display and control panel height, with a view to validate the anthropometric recommendation for the location of the display and control panel in CNC machines. Methods The postural discomforts associated with CNC machines were studied in 122 male operators using Corlett and Bishop's body part discomfort mapping, subject information, and discomfort level at various time intervals from starting to end of a shift. This information was collected using a questionnaire. Statistical analysis was carried out using ANOVA. Results Neck discomfort due to the positioning of the machine displays, and shoulder and arm discomfort due to the positioning of controls were identified as common health issues in the operators of these machines. The study revealed that 45.9% of machine operators reported discomfort in the lower back, 41.8% in the neck, 22.1% in the upper-back, 53.3% in the shoulder and arm, and 21.3% of the operators reported discomfort in the leg. Conclusion Discomfort increased with the progress of the day and was highest at the end of a shift; subject age had no effect on patient tendency to experience discomfort levels. PMID:22993720

Sankaranarayanasamy, Krishnasamy; Ganguli, Anindya Kumar

2012-01-01

275

National Ignition Facility (NIF) Control Network Design and Analysis  

International Nuclear Information System (INIS)

The control network for the National Ignition Facility (NIF) is designed to meet the needs for common object request broker architecture (CORBA) inter-process communication, multicast video transport, device triggering, and general TCP/IP communication within the NIF facility. The network will interconnect approximately 650 systems, including the embedded controllers, front-end processors (FEPs), supervisory systems, and centralized servers involved in operation of the NIF. All systems are networked with Ethernet to serve the majority of communication needs, and asynchronous transfer mode (ATM) is used to transport multicast video and synchronization triggers. CORBA software infra-structure provides location-independent communication services over TCP/IP between the application processes in the 15 supervisory and 300 FEP systems. Video images sampled from 500 video cameras at a 10-Hz frame rate will be multicast using direct ATM Application Programming Interface (API) communication from video FEPs to any selected operator console. The Ethernet and ATM control networks are used to broadcast two types of device triggers for last-second functions in a large number of FEPs, thus eliminating the need for a separate infrastructure for these functions. Analysis, design, modeling, and testing of the NIF network has been performed to provide confidence that the network design will meet NIF control requirements

276

Control rod drop transient analysis and incident recognition  

International Nuclear Information System (INIS)

A control rod drop incident is a relatively frequent transient over the lifetime of a pressurized water reactor. In order to distinguish this particular incident from other similar depressurized events, the transient nuclear and thermal hydraulic characteristics are identified so that the operator can immediately recognize and effectively confirm the incident. The results of this investigation can be used in operator training programs to identify various anticipated transients and, therefore, take proper actions to mitigate the consequences. The investigation of this incident uses the RETRAN system analysis computer code for the Nuclear Project Nos. 1 and 4 currently being constructed by the Washington Public Power Supply System. The dropped control rod transient is simulated by initiating a reactivity reduction at 0.001 seconds after steady-state initialization. A comparison of the transient parameters among a number of similar depressurized incidents is also included

277

Convergence Analysis of a Mixed Controlled Adaptive Algorithm  

Directory of Open Access Journals (Sweden)

Full Text Available A newly developed adaptive scheme for system identification is proposed. The proposed algorithm is a mixture of two norms, namely, the -norm and the -norm ( , where a controlling parameter in the range is used to control the mixture of the two norms. Existing algorithms based on mixed norm can be considered as a special case of the proposed algorithm. Therefore, our algorithm can be seen as a generalization to these algorithms. The derivation of the algorithm and its convexity property are reported and detailed. Also, the first moment behaviour as well as the second moment behaviour of the weights is studied. Bounds for the step size on the convergence of the proposed algorithm are derived, and the steady-state analysis is carried out. Finally, simulation results are performed and are found to corroborate with the theory developed.

Zidouri Abdelmalek

2010-01-01

278

Error analysis of acceleration control loops of a synchrotron  

International Nuclear Information System (INIS)

For beam control during acceleration, it is conventional to derive the frequency from an external reference, be it a field marker or an external oscillator, to provide phase and radius feedback loops to ensure the phase stability, radial position and emittance integrity of the beam. The open and closed loop behaviors of both feedback control and their response under the possible frequency, phase and radius errors are derived from fundamental principles and equations. The stability of the loops is investigated under a wide range of variations of the gain and time delays. Actual system performance of the AGS Booster is analyzed and compared to commissioning experiences. Such analysis is useful for setting design criteria and tolerances for new proton synchrotrons. 4 refs., 13 figs

279

Propulsion/flight control integration technology (PROFIT) design analysis status  

Science.gov (United States)

The propulsion flight control integration technology (PROFIT) program was designed to develop a flying testbed dedicated to controls research. The preliminary design, analysis, and feasibility studies conducted in support of the PROFIT program are reported. The PROFIT system was built around existing IPCS hardware. In order to achieve the desired system flexibility and capability, additional interfaces between the IPCS hardware and F-15 systems were required. The requirements for additions and modifications to the existing hardware were defined. Those interfaces involving the more significant changes were studied. The DCU memory expansion to 32K with flight qualified hardware was completed on a brassboard basis. The uplink interface breadboard and a brassboard of the central computer interface were also tested. Two preliminary designs and corresponding program plans are presented.

Carlin, C. M.; Hastings, W. J.

1978-01-01

280

Nanosilicon properties, synthesis, applications, methods of analysis and control  

CERN Document Server

Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and pro...

Ischenko, Anatoly A; Aslalnov, Leonid A

2015-01-01

 
 
 
 
281

Multi-intersection Traffic Light Control Using Infinitesimal Perturbation Analysis  

CERN Document Server

We address the traffic light control problem for multiple intersections in tandem by viewing it as a stochastic hybrid system and developing a Stochastic Flow Model (SFM) for it. Using Infinitesimal Perturbation Analysis (IPA), we derive on-line gradient estimates of a cost metric with respect to the controllable green and red cycle lengths. The IPA estimators obtained require counting traffic light switchings and estimating car flow rates only when specific events occur. The estimators are used to iteratively adjust light cycle lengths to improve performance and, in conjunction with a standard gradient-based algorithm, to obtain optimal values which adapt to changing traffic conditions. Simulation results are included to illustrate the approach.

Geng, Yanfeng

2012-01-01

282

An Analysis of the PLLs With Secondary Control Path  

DEFF Research Database (Denmark)

The phase-locked loops (PLLs) are widely used in different areas of applications particularly for synchronization and control purposes in grid connected applications. A major challenge associated with the PLLs is how to improve their dynamic performance without jeopardizing their stability and filtering capability. Recently, some approaches based on adding a secondary control path (SCP) to the PLL structure have been proposed to deal with this challenge. The objective of this letter is to briefly analyze these approaches. The study starts with an overview of the PLLs with SCP. The letter proceeds with the small-signal modeling of some of these PLLs, which significantly simplifies the analysis. Using these models, the effects of adding the SCP on the PLL structure are studied. The obtained results show that the SCP may not be a practical approach to improve the PLL dynamic performance as it aggravates the stability problem.

Golestan, Saeed; Ramezani, Malek

2014-01-01

283

Dysregulation of pathways involved in the processing of cancer and microenvironment information in MCA + TPA transformed C3H/10T1/2 cells.  

Science.gov (United States)

The two-stage cell transformation assay is an in vitro model cell culture system to identify the ability of chemicals to act as initiators or promoters of cell transformation and also to study the cellular and molecular mechanisms of chemically induced morphological and neoplastic cell transformation. The global gene expression profiles of 3-methylcholanthrene (MCA) + 12-O-tetradecanoylphorbol-13-acetate (TPA)-transformed C3H/10T1/2 cells are not known. Therefore, we have investigated the global transcriptional profile of MCA + TPA-transformed C3H10T1/2 cells using an 8 × 60 k probe microarray. The study revealed a differential regulation of pathways and gene expressions. Multifold dysregulation was seen in pathways of cancer, phagosomal activity, and tumor cell microenvironment information processing systems, notably the neuroactive ligand-receptor interaction, actin cytoskeleton regulation, tight junction, axon guidance, and cell adhesion molecules. The genes FGF1, EIF4E1B, MAGI1, and GRIA3 showed upregulation; these encoded the pluripotent fibroblast growth factor, the translation initiation factor, the tight junction scaffolding protein, and the antiapoptotic as well as the enhancer of proliferation and migration, respectively. The genes CXCL7/CXCL5/CXCL12, H2DMB1, and HSPA1A showed downregulation; these encoded the chemotactic agent protein, the protein involved in MHC class II antigen processing/presentation or participating in cell adhesion/phagosomal activity/autoimmune disorder, and the chaperone protein stabilizing the existing as well as newly translated cytosolic/organelle proteins against aggregation, respectively. By loss or gain of function, these dysregulated genes apparently seem to reprogram cells for apoptosis or proliferation and support their transformation into the tumor cell phenotype. The observed molecular changes can be seen as molecular signatures of transformed cells and can be of use as objective evidences to C3H/10T1/2 cell transformation assay in investigations on the carcinogenic potential of chemicals and their mechanism of actions using in vitro carcinogenesis method. PMID:23519560

Priya, Shivam; Nigam, Akanksha; Bajpai, Preeti; Kumar, Sushil

2013-04-01

284

Statistical analysis of the blast furnace process output parameter using arima control chart with proposed methodology of control limits setting  

Directory of Open Access Journals (Sweden)

Full Text Available The paper deals with the statistical analysis of the selected parameter of the blast furnace process. It was proved that analyzed measurements have been autocorrelated. ARIMA control chart was selected for their analysis as a very useful statistical process control (SPC method. At first the methodology for control limits setting in ARIMA control charts considering the time series outlier analysis as an integral part of the ARIMA model building was designed. Then this proposal was applied to the statistical analysis of the selected blast furnace process output parameter with the aim to compare two production methods.

D. Noskievi?ová

2009-10-01

285

Control of pneumatic transfer system for neutron activation analysis  

International Nuclear Information System (INIS)

Pneumatic transfer system(PTS) is one of the facilities to be used in irradiation of target materials for neutron activation analysis(NAA) in the research reactor. There are two systems the manual and the automatic system in PTS of HANARO research reactor. The pneumatic transfer system consists of many devices, sends and loads the capsules from NAA laboratory into three holes in the reflector tank of reactor and retrieves irradiated capsules after irradiation. This report describes the part's design, control system and the operation procedures. All the algorithm described in the text will be used for maintenance and upgrading

286

Control of pneumatic transfer system for neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

Pneumatic transfer system(PTS) is one of the facilities to be used in irradiation of target materials for neutron activation analysis(NAA) in the research reactor. There are two systems the manual and the automatic system in PTS of HANARO research reactor. The pneumatic transfer system consists of many devices, sends and loads the capsules from NAA laboratory into three holes in the reflector tank of reactor and retrieves irradiated capsules after irradiation. This report describes the part's design, control system and the operation procedures. All the algorithm described in the text will be used for maintenance and upgrading.

Jung, H. S.; Chung, Y. S.; Wu, J. S.; Kim, H. K.; Choi, Y. S.; Kim, S. H.; Moon, J. H.; Baek, S. Y

2000-06-01

287

Cost-benefit analysis in animal disease control  

International Nuclear Information System (INIS)

Animal health economics is a relatively new discipline which is progressively developing a solid framework of concepts, procedures and data to support the decision making process in optimizing animal health management. Research in this field deals primarily with three interrelated aspects: (1) quantifying the financial effects of animal diseases, (2) developing methods for optimizing decisions when individual animals, herds or populations are affected, and (3) determining the costs and benefits of disease control measures. In the paper the four most common economic modelling techniques in animal health economics (i.e. partial budgeting, cost-benefit analysis, decision analysis, and systems simulation) are described and applied on three levels of veterinary decision making: the animal, herd and national level. Outcomes so far are summarized, and shortcomings indicated and discussed. The importance of a close link between economics and epidemiology is stressed for future development, as well as the need for, and possibilities of, an international exchange of models and procedures. (author)

288

Microcomputer-based pneumatic controller for neutron activation analysis  

International Nuclear Information System (INIS)

A microcomputer-based pneumatic controller for neutron activation analysis was designed and built at the Savannah River Laboratory for analysis of large numbers of geologic samples for locating potential supplies of uranium ore for the National Uranium Resource Evaluation program. In this system, commercially available microcomputer logic modules are used to transport sample capsules through a network of pressurized air lines. The logic modules are interfaced to pneumatic valves, solenoids, and photo-optical detectors. The system operates from programs stored in firmware (permanent software). It also commands a minicomputer and a hard-wired pulse height analyzer for data collection and bookkeeping tasks. The advantage of the system is that major system changes can be implemented in the firmware with no hardware changes. This report describes the hardware, firmware, and software for the electronics system

289

Analysis of film structures using controlled anodic oxidation of metals  

International Nuclear Information System (INIS)

Possibility of using controlled anodic oxidation for analysis of film structures on the basis of anodized metals (Nb, Ta, Al, etc.) in the regimes of voltage linear scanning in time on electrolyte cell and constant current density is considered. Method for calculating oxygen concentration profiles of structures oxide-metal, metal-oxide, metal-oxide-metal, metal-metal is proposed. Comparative analysis of experimentally obtained concentration profiles by methods of the anodic oxidation auger-spectroscopy methods in combination with surface ion spraying for model structures Nb-Nb2O5-Nb and Nb-Al-Nb-Al-Nb-Si is carried out. Possibility of evaluating degree of roughness for interface boundary of metal-dielectric substrate (within the microbulge range of 2-20 nm) is determined

290

Analysis of rotor slotting saliency in induction motor sensorless control  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with induction machines study by Finite Element Analysis (FEA) for position sensorless control drives based on rotating voltage carrier injection. It focuses the analysis of the rotor slotting saliency, under the variations of: (1) supply of the machine (both the high frequency rotating voltage carrier and the fundamental frequency supply), (2) reference flux of the drive, (3) load torque, and (4) rotor geometry design. The relative spatial harmonic of the stator inductance space-vector responsible for the rotor slotting effect has been chosen as an index for evaluating the response to the high frequency carrier. A methodology for retrieving the stator inductance space-vector from a FEA is proposed as well. Results of the variation of the rotor slotting spatial harmonic of the stator inductance with the carrier frequency, the rotor flux linkage, the load torque and the rotor geometry are presented. (author)

Pucci, Marcello; Serporta, Calogero [I.S.S.I.A.-C.N.R. (Institute on Intelligent Systems for the Automation), Via Dante, 12, 90100 Palermo (Italy)

2011-02-15

291

Deviation from optimal vascular caliber control at middle cerebral artery bifurcations harboring aneurysms.  

Science.gov (United States)

Cerebral aneurysms form preferentially at arterial bifurcations. The vascular optimality principle (VOP) decrees that minimal energy loss across bifurcations requires optimal caliber control between radii of parent (r0) and daughter branches (r1 and r2): r0(n)=r1(n)+r2(n), with n approximating three. VOP entails constant wall shear stress (WSS), an endothelial phenotype regulator. We sought to determine if caliber control is maintained in aneurysmal intracranial bifurcations. Three-dimensional rotational angiographic volumes of 159 middle cerebral artery (MCA) bifurcations (62 aneurysmal) were processed using 3D gradient edge-detection filtering, enabling threshold-insensitive radius measurement. Radius ratio (RR)=r0(3)/(r1(3)+r2(3)) and estimated junction exponent (n) were compared between aneurysmal and non-aneurysmal bifurcations using Student t-test and Wilcoxon rank-sum analysis. The results show that non-aneurysmal bifurcations display optimal caliber control with mean RR of 1.05 and median n of 2.84. In contrast, aneurysmal bifurcations had significantly lower RR (0.76, p<.0001) and higher n (4.28, p<.0001). Unexpectedly, 37% of aneurysmal bifurcations revealed a daughter branch larger than its parent vessel, an absolute violation of optimality, not witnessed in non-aneurysmal bifurcations. The aneurysms originated more often off the smaller daughter (52%) vs. larger daughter branch (16%). Aneurysm size was not statistically correlated to RR or n. Aneurysmal males showed higher deviation from VOP. Non-aneurysmal MCA bifurcations contralateral to aneurysmal ones showed optimal caliber control. Aneurysmal bifurcations, in contrast to non-aneurysmal counterparts, disobey the VOP and may exhibit dysregulation in WSS-mediated caliber control. The mechanism of this focal divergence from optimality may underlie aneurysm pathogenesis and requires further study. PMID:25242132

Baharoglu, Merih I; Lauric, Alexandra; Wu, Chengyuan; Hippelheuser, James; Malek, Adel M

2014-10-17

292

Economic analysis of HPAI control in the Netherlands I: epidemiological modelling to support economic analysis.  

Science.gov (United States)

Economic analysis of control strategies for contagious diseases is a necessity in the development of contingency plans. Economic impacts arising from epidemics such as highly pathogenic avian influenza (HPAI) consist of direct costs (DC), direct consequential costs (DCC), indirect consequential costs (ICC) and aftermath costs (AC). Epidemiological models to support economic analysis need to provide adequate outputs for these critical economic parameters. Of particular importance for DCC, ICC and AC is the spatial production structure of a region. Spatial simulation models are therefore particularly suited for economic analysis; however, they often require a large number of parameters. The aims of this study are (i) to provide an economic rationale of epidemiological modelling in general, (ii) to provide a transparent description of the parameterization of a spatially based epidemiological model for the analysis of HPAI control in the Netherlands and (iii) to discuss the validity and usefulness of this model for subsequent economic analysis. In the model, HPAI virus transmission occurs via local spread and animal movements. Control mechanisms include surveillance and tracing, movement restrictions and depopulation. Sensitivity analysis of key parameters indicated that the epidemiological outputs with the largest influence on the economic impacts (i.e. epidemic duration and number of farms in the movement restriction zone) were more robust than less influential indicators (i.e. number of infected farms). Economically relevant outputs for strategy comparison were most sensitive to the relative role of the different transmission parameters. The default simulation and results of the sensitivity analysis were consistent with the general outcomes of known HPAI models. Comparison was, however, limited due to the absence of some economically relevant outputs. It was concluded that the model creates economically relevant, adequate and credible output for subsequent use in economic analysis. A detailed economic analysis is presented in a subsequent article. PMID:23066736

Longworth, N; Mourits, M C M; Saatkamp, H W

2014-06-01

293

Process control analysis of IMRT QA: implications for clinical trials  

International Nuclear Information System (INIS)

The purpose of this study is two-fold: first is to investigate the process of IMRT QA using control charts and second is to compare control chart limits to limits calculated using the standard deviation (?). Head and neck and prostate IMRT QA cases from seven institutions in both academic and community settings are considered. The percent difference between the point dose measurement in phantom and the corresponding result from the treatment planning system (TPS) is used for analysis. The average of the percent difference calculations defines the accuracy of the process and is called the process target. This represents the degree to which the process meets the clinical goal of 0% difference between the measurements and TPS. IMRT QA process ability defines the ability of the process to meet clinical specifications (e.g. 5% difference between the measurement and TPS). The process ability is defined in two ways: (1) the half-width of the control chart limits, and (2) the half-width of ±3? limits. Process performance is characterized as being in one of four possible states that describes the stability of the process and its ability to meet clinical specifications. For the head and neck cases, the average process target across institutions was 0.3% (range: -1.5% to 2.9%). The average process ability using control chart limits was 7.2% (range: 5.3% to 9.8%) compared to 6.7% (range: 5.3% to 8.2%) using standard deviation limits. For the prostate cases, the average processthe prostate cases, the average process target across the institutions was 0.2% (range: -1.8% to 1.4%). The average process ability using control chart limits was 4.4% (range: 1.3% to 9.4%) compared to 5.3% (range: 2.3% to 9.8%) using standard deviation limits. Using the standard deviation to characterize IMRT QA process performance resulted in processes being preferentially placed in one of the four states. This is in contrast to using control charts for process characterization where the IMRT QA processes were spread over three of the four states with none of the processes in the ideal state. Control charts may be used for IMRT QA in clinical trials to categorize process performance, minimize protocol variation and guide process improvements. For the duration of an institution's participation in a protocol, updated control charts can be periodically sent to the protocol QA center to document continued process performance to protocol specifications

294

Process control analysis of IMRT QA: implications for clinical trials  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is two-fold: first is to investigate the process of IMRT QA using control charts and second is to compare control chart limits to limits calculated using the standard deviation ({sigma}). Head and neck and prostate IMRT QA cases from seven institutions in both academic and community settings are considered. The percent difference between the point dose measurement in phantom and the corresponding result from the treatment planning system (TPS) is used for analysis. The average of the percent difference calculations defines the accuracy of the process and is called the process target. This represents the degree to which the process meets the clinical goal of 0% difference between the measurements and TPS. IMRT QA process ability defines the ability of the process to meet clinical specifications (e.g. 5% difference between the measurement and TPS). The process ability is defined in two ways: (1) the half-width of the control chart limits, and (2) the half-width of {+-}3{sigma} limits. Process performance is characterized as being in one of four possible states that describes the stability of the process and its ability to meet clinical specifications. For the head and neck cases, the average process target across institutions was 0.3% (range: -1.5% to 2.9%). The average process ability using control chart limits was 7.2% (range: 5.3% to 9.8%) compared to 6.7% (range: 5.3% to 8.2%) using standard deviation limits. For the prostate cases, the average process target across the institutions was 0.2% (range: -1.8% to 1.4%). The average process ability using control chart limits was 4.4% (range: 1.3% to 9.4%) compared to 5.3% (range: 2.3% to 9.8%) using standard deviation limits. Using the standard deviation to characterize IMRT QA process performance resulted in processes being preferentially placed in one of the four states. This is in contrast to using control charts for process characterization where the IMRT QA processes were spread over three of the four states with none of the processes in the ideal state. Control charts may be used for IMRT QA in clinical trials to categorize process performance, minimize protocol variation and guide process improvements. For the duration of an institution's participation in a protocol, updated control charts can be periodically sent to the protocol QA center to document continued process performance to protocol specifications.

Pawlicki, Todd; Rice, Roger K [Department of Radiation Oncology, University of California, San Diego, La Jolla, CA 92093 (United States); Yoo, Sua [Department of Radiation Oncology, Duke University, Durham, NC 27710 (United States); Court, Laurence E [Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA 02115 (United States); McMillan, Sharon K [Radiation Oncology Department, Decatur Memorial Hospital, Decatur, IL 62526 (United States); Russell, J Donald [Community Cancer Center, Roseburg, OR 97470 (United States); Pacyniak, John M [Hulston Cancer Center, Cox Health Systems, Springfield, MO 65807 (United States); Woo, Milton K; Basran, Parminder S [Medical Physics Department, Odette Cancer Centre, Toronto, ON (Canada); Boyer, Arthur L [Scott and White Memorial Hospital, Temple, TX 76508 (United States); Bonilla, Claribel [Department of Industrial and Systems Engineering, University of San Diego, San Diego, CA 92110 (United States)], E-mail: tpaw@ucsd.edu

2008-09-21

295

Analysis of HPGe Spectrometer Stability - Internal Quality Control  

International Nuclear Information System (INIS)

Laboratory for Nuclear and Plasma Physics, Institute ''Vinea'' is authorized and accredited in accordance with ISO/IEC 17025 for measurements of radionuclide content in environmental samples. In accordance with a standards request and international recommendations, TCS No. 24, Quality System Implementation for Nuclear Analytical Techniques, permanent internal quality control of semiconductor HPGe spectrometer has been conducted. Periodical testing of spectrometer characteristics and creation of control charts are included in internal quality control processes. The evaluation of the measuring system can be performed by periodical testing as follows: FWHM chart provides evaluation of the resolution of a detector. Variation of the FWHM could be caused by electronic noise inside the detector, or might indicate a vacuum problem; FWTM chart allows to monitor tailing due to damage of the detection crystal, bad P/Z ration may indicate a leakage current; The ratio FWHM/FWTM for different gamma ray energies allows to monitor the quality of the detector; Activity chart allows to monitor the stability of the whole method; Background chart might discover contamination; Peak position chart provide indications for electronic stability and the influence of environmental conditions such as temperature or humidity. Point sources 60Co and 137Cs were used as a control sources for FWHM, FWTM, FWHM/FWTM ratio and peak position testing. Presented control charts, for a period June - December 2010, were used for an analysis of spectrometer stability. These charts show that performances of analyzed HPGe spectrometer were stable, meaning that measurements results for environmental samples could be considered as reliable, i.e. that the practice of Laboratory fully consists with an international recommendations. (author)

296

Validation of the REBUS-3/RTC methodologies for EBR-II core-follow analysis  

International Nuclear Information System (INIS)

Operations and material control and accountancy (MCA) requirements for the Fuel Cycle Facility (FCF) will demand accurate prediction of the mass flow from Experimental Breeder Reactor-II (EBR-II) into the facility. This will require validated calculational tools that can predict the burnup and isotopic distribution in irradiated binary- and ternary-fueled Mark III, Mark IV, and Mark V assemblies. The present study demonstrates that the REBUS-3/RCT methodologies can meet these requirements. Validation is achieved via a two-step procedure. First, a set of detailed core-follow depletion calculations using the REBUS-3/RCT codes is performed for an extensive series of EBR-II runs. Second, the results of this analysis are compared with experimental determinations of burnup and U and Pu isotopic weight fractions that have been measured in IFR fueled test assemblies irradiated in EBR-II. The results of these comparisons are very good and indicate that mass flow predictions based on the methods used in this study are adequate for operational and MCA requirements in FCF

297

UHB demonstrator interior noise control flight tests and analysis  

Science.gov (United States)

The measurement and analysis of MD-UHB (McDonnell Douglas Ultra High Bypass) Demonstrator noise and vibration flight test data are described as they relate to passenger cabin noise. The analyses were done to investigate the interior noise characteristics of advanced turboprop aircraft with aft-mounted engines, and to study the effectiveness of selected noise control treatments in reducing passenger cabin noise. The UHB Demonstrator is an MD-80 test aircraft with the left JT8D engine replaced with a prototype UHB engine. For these tests, the UHB engine was a General Electric Unducted Fan, with either 8x8 or 10x8 counter-rotating propeller configurations. Interior noise level characteristics were studied for several altitudes and speeds, with emphasis on high altitude (35,000 ft), high speed (0.75 Mach) cruise conditions. The effectiveness of several noise control treatments was evaluated based on cabin noise measurements. The important airborne and structureborne transmission paths were identified for both tonal and broadband sources using the results of a sound intensity survey, exterior and interior noise and vibration data, and partial coherence analysis techniques. Estimates of the turbulent boundary layer pressure wavenumber-frequency spectrum were made, based on measured fuselage noise levels.

Simpson, M. A.; Druez, P. M.; Kimbrough, A. J.; Brock, M. P.; Burge, P. L.; Mathur, G. P.; Cannon, M. R.; Tran, B. N.

1989-01-01

298

An Analysis of the Control Hierarchy Modelling of the CMS Detector Control System  

Science.gov (United States)

The supervisory level of the Detector Control System (DCS) of the CMS experiment is implemented using Finite State Machines (FSM), which model the behaviours and control the operations of all the sub-detectors and support services. The FSM tree of the whole CMS experiment consists of more than 30.000 nodes. An analysis of a system of such size is a complex task but is a crucial step towards the improvement of the overall performance of the FSM system. This paper presents the analysis of the CMS FSM system using the micro Common Representation Language 2 (mcrl2) methodology. Individual mCRL2 models are obtained for the FSM systems of the CMS sub-detectors using the ASF+SDF automated translation tool. Different mCRL2 operations are applied to the mCRL2 models. A mCRL2 simulation tool is used to closer examine the system. Visualization of a system based on the exploration of its state space is enabled with a mCRL2 tool. Requirements such as command and state propagation are expressed using modal mu-calculus and checked using a model checking algorithm. For checking local requirements such as endless loop freedom, the Bounded Model Checking technique is applied. This paper discusses these analysis techniques and presents the results of their application on the CMS FSM system.

Hwong, Yi Ling; Willemse, Tim; Kusters, Vincent; Bauer, Gerry; Beccati, Barbara; Behrens, Ulf; Biery, Kurt; Bouffet, Olivier; Branson, James; Bukowiec, Sebastian; Cano, Eric; Cheung, Harry; Ciganek, Marek; Cittolin, Sergio; Coarasa, Jose Antonio; Deldicque, Christian; Dupont, Aymeric; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gomez-Reino, Robert; Holzner, Andre; Hatton, Derek; Masetti, Lorenzo; Meijers, Frans; Meschi, Emilio; Mommsen, Remigius K.; Moser, Roland; O'Dell, Vivian; Orsini, Luciano; Paus, Christoph; Petrucci, Andrea; Pieri, Marco; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schieferdeckerb, Philipp; Schwick, Christoph; Shpakov, Dennis; Simon, Michal; Sumorok, Konstanty

2011-12-01

299

An Analysis of the Control Hierarchy Modelling of the CMS Detector Control System  

International Nuclear Information System (INIS)

The supervisory level of the Detector Control System (DCS) of the CMS experiment is implemented using Finite State Machines (FSM), which model the behaviours and control the operations of all the sub-detectors and support services. The FSM tree of the whole CMS experiment consists of more than 30.000 nodes. An analysis of a system of such size is a complex task but is a crucial step towards the improvement of the overall performance of the FSM system. This paper presents the analysis of the CMS FSM system using the micro Common Representation Language 2 (mcrl2) methodology. Individual mCRL2 models are obtained for the FSM systems of the CMS sub-detectors using the ASF+SDF automated translation tool. Different mCRL2 operations are applied to the mCRL2 models. A mCRL2 simulation tool is used to closer examine the system. Visualization of a system based on the exploration of its state space is enabled with a mCRL2 tool. Requirements such as command and state propagation are expressed using modal mu-calculus and checked using a model checking algorithm. For checking local requirements such as endless loop freedom, the Bounded Model Checking technique is applied. This paper discusses these analysis techniques and presents the results of their application on the CMS FSM system.

300

The use of lac-type promoters in control analysis  

DEFF Research Database (Denmark)

For control analysis, it is necessary to modulate the activity of an enzyme around its normal level and measure the changes in steady-state fluxes or concentrations. We describe an improved method for effecting the modulation, as elaborated for Escherichia coli. The chromosomal gene, encoding the enzyme of interest, is put under the control of a lacUV5 or a tacI promoter. The alternative use of the two promoters leads to an expression range which should make it suitable for the use in control analysis of many enzymes. The lacUV5 promoter should be used when the wild-type expression level is low, the tacI promoter when the latter is high. The endogenous lac operon is placed under the control of a second copy of the lacUV5 promoter and a lacYam mutation (eliminating lactose permease, the transport system for the inducer isopropyl-thio-beta-D-galactoside) is introduced. The method was demonstrated experimentally by constructing E. coli strains, in which the chromosomal atp operon is transcribed from the lacUV5 and the tacI promoter. We measured the concentration of the c subunit of H+-ATPase, and found that the expression of this enzyme could be modulated between non-detectable levels and up to five times the wild-type level. Thus, in the absence of inducer, no expression of atp genes could be detected when the atp operon was controlled by the lacUV5 promoter, and we estimate that the expression was less than 0.0025 times the wild-type level. We show that the introduction of a lac Y mutation facilitated the attainment of steady induction levels of partially induced cells. The mutation also reduced positive cooperativity in the dependence of expression on the concentration of isopropyl-thio-beta-D-galactoside (the inducer) and shifted the concentration of inducer needed for half maximum induction to higher values. These properties should facilitate the experimental modulation of the enzyme activity by varying the concentration of the inducer.

Jensen, Peter Ruhdal; Michelsen, Ole

1993-01-01

 
 
 
 
301

Up and down conversion fluorescence studies on combustion synthesized Yb3+/Yb2+: MO-Al2O3 (M=Ca, Sr and Ba) phosphors  

International Nuclear Information System (INIS)

The ytterbium ions doped MO-Al2O3 (M=Ca, Sr and Ba) phosphors have been synthesized through combustion technique and their up and down conversion fluorescence properties have been studied and compared. The samples were calcinated at different temperatures and their FTIR and XRD spectra have shown a close relationship. With 976 nm excitation all these phosphors show cooperative upconversion emission at 488 nm from the pairs of two Yb3+ ions along with an unexpected broad upconversion band in the blue green region and has been assigned to arise from the defect centers. Contrary to this upconversion emission, calcium aluminate phosphor exhibits bright and very broad down-conversion fluorescence (FWHM?160 nm) upon UV (266 nm) excitation due to Yb2+ ions. The inter-conversion between the 3+ and 2+ valence states of Yb ion has been observed on calcinations of samples in open atmosphere and has been correlated to the emission properties. The Yb2+ ions containing calcium aluminate phosphor has been found suitable for producing broad band light in the visible region (white light). Lifetime of the emitting states of Yb3+ and Yb2+ ions have also been measured and discussed.

302

Crystal structure and properties of the new vanadyl(IV)phosphates Na2MVO(PO4)2, M=Ca and Sr  

International Nuclear Information System (INIS)

Two new complex vanadyl(IV)phosphates Na2MVO(PO4)2 (M=Ca, Sr) were synthesized in evacuated quartz ampoules and investigated by means of X-ray diffraction, electron microscopy, DTA, ESR and magnetic susceptibility measurements. The crystal structure of Na2SrVO(PO4)2 was solved ab initio from X-ray powder diffraction data. Both compounds are isostructural: a=10.5233(3) A, b=6.5578(2) A, c=10.0536(3) A and a=10.6476(3) A, b=6.6224(2) A, c=10.2537(3) A for Ca and Sr, respectively; S.G. Pnma, Z=4. The compounds have a three-dimensional structure consisting of V4+O6 octahedra connected by PO4 tetrahedra via five of the six vertexes forming a framework with cross-like channels. The strontium and sodium atoms are located in the channels in an ordered manner. Electron diffraction as well as high-resolution electron microscopy confirmed the structure solution. The new vanadylphosphates are Curie-Weiss paramagnets in a wide temperature range down to 2 K with ?=12 and 5 K for Ca and Sr phases, respectively

303

Production and in vitro characterization of 3D porous scaffolds made of magnesium carbonate apatite (MCA)/anionic collagen using a biomimetic approach.  

Science.gov (United States)

3D porous scaffolds are relevant biomaterials to bone engineering as they can be used as templates to tissue reconstruction. The aim of the present study was to produce and characterize in vitro 3D magnesium-carbonate apatite/collagen (MCA/col) scaffolds. They were prepared by using biomimetic approach, followed by cross-linking with 0.25% glutaraldehyde solution (GA) and liofilization. Results obtained with Fourier-transform infrared spectroscopy (FT-IR) confirmed the type-B carbonate substitution, while by X-ray diffraction (XRD), a crystallite size of ~10nm was obtained. Optical and electron microscopy showed that the cylindrical samples exhibited an open-porous morphology, with apatite nanocrystals precipitated on collagen fibrils. The cross-linked 3D scaffolds showed integrity when immersed in culture medium up to 14 days. Also, the immersion of such samples into an acid buffer solution, to mimic the osteoclastic resorption environment, promotes the release of important ions for bone repair, such as calcium, phosphorus and magnesium. Bone cells (SaOs2) adhered, and proliferated on the 3D composite scaffolds, showing that synthesis and the cross-linking processes did not induce cytotoxicity. PMID:23910332

Sader, Marcia S; Martins, Virginia C A; Gomez, Santiago; LeGeros, Racquel Z; Soares, Gloria A

2013-10-01

304

Second-Order Analysis for Control Constrained Optimal Control Problems of Semilinear Elliptic Systems  

International Nuclear Information System (INIS)

This paper presents a second-order analysis for a simple model optimal control problem of a partial differential equation, namely, a well-posed semilinear elliptic system with constraints on the control variable only. The cost to be minimized is a standard quadratic functional. Assuming the feasible set to be polyhedric, we state necessary and sufficient second-order optimality conditions, including a characterization of the quadratic growth condition. Assuming that the second-order sufficient condition holds, we give a formula for the second-order expansion of the value of the problem as well as the directional derivative of the optimal control, when the cost function is perturbed. Then we extend the theory of second-order optimality conditions to the case of vector-valued controls when the feasible set is defined by local and smooth convex constraints. When the space dimension n is greater than 3, the results are based on a two norms approach, involving spaces L2(?) and Ls(?) , with s>n/2

305

An algorithm for control volume analysis of cryogenic systems  

Science.gov (United States)

This thesis presents an algorithm suitable for numerical analysis of cryogenic refrigeration systems. Preliminary design of a cryogenic system commences with a number of decoupling assumptions with regard to the process variables of heat and work transfer (e.g., work input rate, heat loading rates) and state variables (pinch points, momentum losses). Making preliminary performance estimations minimizes the effect of component interactions which is inconsistent with the intent of analysis. A more useful design and analysis tool is one in which no restrictions are applied to the system - interactions become absolutely coupled and governed by the equilibrium state variables. Such a model would require consideration of hardware specifications and performance data and information with respect to the thermal environment. Model output would consist of the independent thermodynamic state variables from which process variables and performance parameters may be computed. This model will have a framework compatible for numerical solution on a digital computer so that it may be interfaced with graphic symbology for user interaction. This algorithm approaches cryogenic problems in a highly-coupled state-dependent manner. The framework for this algorithm revolves around the revolutionary thermodynamic solution technique for computer Aided Thermodynamics (CAT). Fundamental differences exist between the Control Volume (CV) algorithm and CAT, which will be discussed where appropriate.

Stanton, Michael B.

1989-06-01

306

An evaluation of cusum analysis and control charts applied to quantitative gamma-camera uniformity parameters for automated quality control  

International Nuclear Information System (INIS)

itivity of those parameters that appeared to have low sensitivity to change when subjected to control chart analysis. However, there was little difference between the two analysis techniques for the more sensitive parameters. The ROC curves could also be used to provide a method for selecting decision levels, hence establishing an automated method for gamma-camera quality control. (orig.)

307

Austrian meat: Authenticity control by stable isotope analysis  

International Nuclear Information System (INIS)

Full text: The EU has declared that all foodstuff must be able to be traced back from 'fork to farm' to increase the safety of food and the confidence of the consumers in food quality and safety. Additionally, several incidents of 'food diseases and scandals' related with meat (e.g.: BSE, foot and mouth disease, antibiotics abuse, avian flu, etc.) have demonstrated the necessity to trace back the origin of meat, to be able to locate sources of infection/mismanagement. Besides the conventional method of the control of documentation there is the possibility of control of origin by analysing the isotopic composition of meat and herewith controlling the questioned good itself. Stable isotope ratios of the elements HCNOS are varying geographically due to different environmental conditions (e.g.: climate, geology, soil, altitude, geography, etc.) thus every region possesses an individual pattern. The isotopic pattern is imprinted on plants and animals growing in a certain region, and therefore analysis of the stable isotope pattern can allow the identification of agricultural goods from different regions. For the control of origin of Austrian meat about 500 beef and 500 pork samples have been collected from slaughterhouses and were analysed for the isotopic composition of carbon, nitrogen, oxygen and sulphur and compared with the isotopic composition of meat samples from neighbouring countries. As Austria, despite being a small country, is very heterogeneous in its environmtry, is very heterogeneous in its environmental conditions, thus there are significant differences in the isotopic patterns of individual Austrian provinces. The isotopic signature of meat samples from neighbouring countries can overlap with the 'Austrian isotope pattern' due to similar environmental conditions. However, a correct statistical classification has been achieved for 80% and 84% of the analysed beef and pork samples, respectively. If the declared origin of meat can be pinned down to an Austrian province, the discrimination power of the database is even significantly better. (author)

308

Space Station Environmental Control and Life Support System Purge Control Pump Assembly Modeling and Analysis  

Science.gov (United States)

Preliminary results from a thermal/flow analysis of the Purge Control Pump Assembly (PCPA) indicate that pump performance (mass flow rate) is enhanced via cooling of the housing and lowering of the inlet vapor quality. Under a nominal operational profile (25% duty cycle or less), at the maximum motor dissipation, it appears that the peristaltic tubing temperature will still remain significantly below the expected UPA condenser temperature (78 F max versus approximately 105 F in the condenser) permitting condensation in the pump head.

Schunk, R. Gregory; Hunt, Patrick L. (Technical Monitor)

2001-01-01

309

Control-structure-thermal interactions in analysis of lunar telescopes  

Science.gov (United States)

The lunar telescope project was an excellent model for the CSTI study because a telescope is a very sensitive instrument, and thermal expansion or mechanical vibration of the mirror assemblies will rapidly degrade the resolution of the device. Consequently, the interactions are strongly coupled. The lunar surface experiences very large temperature variations that range from approximately -180 C to over 100 C. Although the optical assemblies of the telescopes will be well insulated, the temperature of the mirrors will inevitably fluctuate in a similar cycle, but of much smaller magnitude. In order to obtain images of high quality and clarity, allowable thermal deformations of any point on a mirror must be less than 1 micron. Initial estimates indicate that this corresponds to a temperature variation of much less than 1 deg through the thickness of the mirror. Therefore, a lunar telescope design will most probably include active thermal control, a means of controlling the shape of the mirrors, or a combination of both systems. Historically, the design of a complex vehicle was primarily a sequential process in which the basic structure was defined without concurrent detailed analyses or other subsystems. The basic configuration was then passed to the different teams responsible for each subsystem, and their task was to produce a workable solution without requiring major alterations to any principal components or subsystems. Consequently, the final design of the vehicle was not always the most efficient, owing to the fact that each subsystem design was partially constrained by the previous work. This procedure was necessary at the time because the analysis process was extremely time-consuming and had to be started over with each significant alteration of the vehicle. With recent advances in the power and capacity of small computers, and the parallel development of powerful software in structural, thermal, and control system analysis, it is now possible to produce very detailed analyses of intermediate designs in a much shorter period of time. The subsystems can thus be designed concurrently, and alterations in the overall design can be quickly adopted into each analysis; the design becomes an iterative process in which it is much easier to experiment with new ideas, configurations, and components. Concurrent engineering has the potential to produce efficient, highly capable designs because the effect of one subystem on another can be assessed in much more detail at a very early point in the program. The research program consisted of several tasks: scale a prototype telescope assembly to a 1 m aperture, develop a model of the telescope assembly by using finite element (FEM) codes that are available on site, determine structural deflections of the mirror surfaces due to the temperature variations, develop a prototype control system to maintain the proper shape of the optical elements, and most important of all, demonstrate the concurrent engineering approach with this example. In addition, the software used for the finite element models and thermal analysis was relatively new within the Program Development Office and had yet to be applied to systems this large or complex; understanding the software and modifying it for use with this project was also required. The I-DEAS software by Structural Dynamics Research Corporation (SDRC) was used to build the finite element models, and TMG developed by Maya Heat Transfer Technologies, Ltd. (which runs as an I-DEAS module) was used for the thermal model calculations. All control system development was accomplished with MATRIXX by Integrated Systems, Inc.

Thompson, Roger C.

1992-12-01

310

Analysis and modernization of the INR DTL frequency control system  

International Nuclear Information System (INIS)

Results of the INR DTL frequency control system modeling are described. Methods of the control system quality improving by means of right choice of the heater and the control valve parameters are presented. The ways of the existing control system up-grade with using of the up-to-date microprocessor controller for the heater and control valve operation are selected

311

Costing and cost analysis in randomized controlled trials: caveat emptor.  

Science.gov (United States)

This article provides an overview of the central issues regarding cost valuation and analysis for a decision maker's evaluation of costing performed within randomized controlled trials (RCTs). Costing involves specific choices for valuation and analysis that involve trade-offs. Understanding these choices and their implications is necessary for proper evaluation of how costs are valued and analyzed within an RCT and cannot be assessed through a checklist of adherence to general principles. Resource costing, the most common method of costing, involves measuring medical service use in study case report forms and translating this use into a cost by multiplying the number of units of each medical service by price weights for those services. A choice must be made as to how detailed the measurement of resources will be. Micro-costing improves the specificity of the cost estimate, but it is often impractical to precisely measure resources at this level and the price weights for these micro-units may not be available. Gross-costing may be more practical, and price weights are often easier to find and are more reliable, but important resource differences between treatment groups may be lost in the bundling of resources. Price weights can either be nationally determined or centre specific, but the appropriate price weight will depend on perspective, convenience, completeness and accuracy. Identifying the resource types and the appropriate price weights for these resources are the essential elements to an accurate valuation of costs. Once medical services are valued, the resulting individual patient cost estimates must be analysed. The difference in the mean cost between treatment groups is the important summary statistic for cost-effectiveness analysis from both the budgetary and the social perspectives. The statistical challenges with cost data typically stem from its skewed distribution and the resulting possibility that the sample mean may be inefficient and possibly inappropriate for statistical inference. Multivariable analysis of cost is useful, even if the data come from an RCT, but the same distributional problems that affect univariate tests of cost also affect use of cost as a dependent variable in a multivariable regression analysis. The generalized linear model (GLM) overcomes many of the problems of more common cost models, but caution must be used when applying this model because it is prone to mis-specification and precision losses in data with a heavy-tailed log error term. Attention to the appropriate cost valuation and analysis techniques reviewed here will help bring the same level of rigor and attention to the methodological issues in cost valuation as is currently applied to clinical evidence within RCTs. PMID:19354338

Polsky, Daniel; Glick, Henry

2009-01-01

312

Efficacy of 5-FU Combined to Na[trans-RuCl4(DMSO)Im], A Novel Selective Antimetastatic Agent, on the Survival Time of Mice With P388 Leukemia, P388/DDP subline and MCa Mammary Carcinoma  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The combinational treatment between the selective antimetastatic agent, sodium-trans-rutheniumtetrachloridedimethylsulfoxideimidazole, Na[trans-RuCl4(DMSO)Im], and the cytotoxic drug 5-fluorouracil (5-FU) on primary tumor growth and on the survival time of experimental tumors results in an effect significantly greater than that of each single agent used alone either with the solid metastasizing MCa mammary carcinoma of the CBA mouse or with the lymphocytic leukemia P388 and its...

Coluccia, M.; Sava, G.; Salerno, G.; Bergamo, A.; Pacor, S.; Mestroni, G.; Alessio, E.

1995-01-01

313

Analysis of Energy Controllers for Enhancement of Energy Flow  

Directory of Open Access Journals (Sweden)

Full Text Available The fast changing energy market has brought the new challenges in the field of transmission systems. Today’s energy transmissionnetworks are not designed for easy voltage flow in a deregulated market and steady state control problems as well as dynamic problem are the result. A new technology in this field, the flexible ac transmission system is gaining popularity in the world due to its enormous advantages.This paper gives an overview of its development; briefly describes its device and explains its effects. Furthermore, because of the tremendous influence on the system by the introduction of flexible ac transmission system, there is a great demand to improve the energy system analysis. Also, this paper present some aspects and direction needed to be studied.

Neetu Mittal

2010-10-01

314

Quality control of coins mint using PIXE and RBS analysis  

Science.gov (United States)

PIXE and RBS analysis is used to investigate the elemental content of modern Lebanese coins, in order to control their minting quality. The coins of interest were 100, 250 and 500 Lebanese Lira (LL), which are mainly bulky metals with or without coated layer. Using 3 MeV protons, proton induced X-ray emission PIXE identified and quantified elements while Rutherford backscattering spectrometry RBS checked the thickness of the coated layer. Indeed, the combination of PIXE and RBS provides a powerful tool to investigate the elemental composition of coins, either modern or ancient. In addition, the experimental protocol was checked by analyzing some other coins of known composition, such as 1-euro and 2-euro.

Roumie, M.; Nsouli, B.; Chalhoub, G.; Hamdan, M.

2010-06-01

315

Quality control of coins mint using PIXE and RBS analysis  

International Nuclear Information System (INIS)

PIXE and RBS analysis is used to investigate the elemental content of modern Lebanese coins, in order to control their minting quality. The coins of interest were 100, 250 and 500 Lebanese Lira (LL), which are mainly bulky metals with or without coated layer. Using 3 MeV protons, proton induced X-ray emission PIXE identified and quantified elements while Rutherford backscattering spectrometry RBS checked the thickness of the coated layer. Indeed, the combination of PIXE and RBS provides a powerful tool to investigate the elemental composition of coins, either modern or ancient. In addition, the experimental protocol was checked by analyzing some other coins of known composition, such as 1-euro and 2-euro.

316

Comparative Analysis of Congestion Control Algorithms Using ns-2  

CERN Document Server

In order to curtail the escalating packet loss rates caused by an exponential increase in network traffic, active queue management techniques such as Random Early Detection (RED) have come into picture. Flow Random Early Drop (FRED) keeps state based on instantaneous queue occupancy of a given flow. FRED protects fragile flows by deterministically accepting flows from low bandwidth connections and fixes several shortcomings of RED by computing queue length during both arrival and departure of the packet. Stochastic Fair Queuing (SFQ) ensures fair access to network resources and prevents a busty flow from consuming more than its fair share. In case of (Random Exponential Marking) REM, the key idea is to decouple congestion measure from performance measure (loss, queue length or delay). Stabilized RED (SRED) is another approach of detecting nonresponsive flows. In this paper, we have shown a comparative analysis of throughput, delay and queue length for the various congestion control algorithms RED, SFQ and REM...

Patel, Sanjeev; Garg, Arjun; Mehrotra, Prateek; Chhabra, Manish

2012-01-01

317

Introduction to time-delay systems analysis and control  

CERN Document Server

The beginning of the 21st century can be characterized as the ”time-delay boom” leading to numerous important results. The purpose of this book is two-fold, to familiarize the non-expert reader with time-delay systems and to provide a systematic treatment of modern ideas and techniques for experts. This book is based on the course ”Introduction to time-delay systems” for graduate students in Engineering and Applied Mathematics that the author taught in Tel Aviv University in 2011-2012 and 2012-2013 academic years. The sufficient background to follow most of the material are the undergraduate courses in mathematics and an introduction to control. The book leads the reader from some basic classical results on time-delay systems to recent developments on Lyapunov-based analysis and design with applications to the hot topics of sampled-data and network-based control. The objective is to provide useful tools that will allow the reader not only to apply the existing methods, but also to develop new ones. It...

Fridman, Emilia

2014-01-01

318

Analysis of Control Strategies for Diode Clamped Multilevel Inverter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the comparison of various Pulse Width Modulation (PWM strategies for the three phase Diode Clamped Multi Level Inverter (DCMLI. The main contribution of this paper is the proposal of new modulation schemes with Variable Amplitude (VA and various new schemes adopting the constant switching frequency and also variable switching frequency multicarrier control freedom degree combination concepts are developed and simulated for the chosen three phase DCMLI. The three phase DCMLI, is controlled in this paper with Sinusoidal PWM (SPWM reference along with triangular carriers and analysis is made among both without carrier overlapping and with Carrier Overlapping (CO techniques to choose the better strategy by performing simulation using MATLAB-SIMULINK. The variation of Total Harmonic Distortion (THD and fundamental RMS output voltage is observed for various modulation indices. It is observed that among the various equal amplitude PWM strategies, COPWM-C provides less THD and higher RMS voltage. It is recognized that among the various variable amplitude PWM strategies, VACOPWM-C provides less THD and VACOPWM-B provides higher RMS voltage. By comparing the equal amplitude PWM strategies with the variable amplitude PWM strategies it is inferred that VACOPWM-C provides less THD and VACOPWM-B provides higher RMS voltage. It is also inferred that carrier overlapping techniques provides better results compared to the without carrier overlapping techniques.

C. R. Balamurugan

2013-05-01

319

Multi-resolution analysis for determining control rod drop time  

International Nuclear Information System (INIS)

This study describes a multi-resolution analysis (MRA) to determine the onset and end drop times of control rods. The measurement test of the drop times of control rods is normally performed during the start-up test of each reactor cycle since it is a crucial safety function to guarantee the reactor safe shutdown. The MRA with wavelet transform is particularly useful in analyzing the onset transients of rod drop as a means of capturing the unique attributes of such signals in an efficient way. This approach also allows the automated determination of rod drop time which reduces the uncertainty induced by ad hoc heuristic approaches. The test signal is generated by adding the random noise measured from real rod drop tests subtracting the wavelet-filtered noise free signal from the noisy signal leaving the noise. The signal is similar to both high sharp spikes noise and sine wave noise from the real voltage trace generated during the rod drop test. The effectiveness of the method is demonstrated by the MRA process. (author)

320

Smart microneedle coatings for controlled delivery and biomedical analysis.  

Science.gov (United States)

Abstract The work presented demonstrates an unconventional approach in the preparation of smart microneedle (MN) coatings utilising electrohydrodynamic atomisation (EHDA) principles. Stainless steel (600-900?µm in height) MNs were coupled to a ground electrode (in the EHDA coating set-up) with the deposition distance and collecting methodology varied for an ethanol:methanol (50:50) vehicle system. The preparation of nano- and micrometre-scaled pharmaceutical coatings was achieved. Fluorescein dye (serving as potential drug, sensory materials or disease state markers) and polyvinylpyrrolidone (PVP, polymer matrix system) formed the remaining components of the coating formulation. Based on these excipients and by varying the coating process, particles (100?nm to 3?µm) and fibres (400?nm to 1?µm) were deposited directly on MNs in controlled and selectable fashion (flow rates variable ?5-50?µL/min, applied voltage variable 6-19?kV). These demonstrated options for multiple targeting and analysis applications. The underlying EHDA process permits room temperature fabrication, controlled output and scale-up potential for emerging MN devices as drug systems or lab-chip testing devices. PMID:24892742

Khan, H; Mehta, P; Msallam, H; Armitage, D; Ahmad, Z

2014-11-01

 
 
 
 
321

Uncertainty Modeling for Structural Control Analysis and Synthesis  

Science.gov (United States)

The development of an accurate model of uncertainties for the control of structures that undergo a change in operational environment, based solely on modeling and experimentation in the original environment is studied. The application used throughout this work is the development of an on-orbit uncertainty model based on ground modeling and experimentation. A ground based uncertainty model consisting of mean errors and bounds on critical structural parameters is developed. The uncertainty model is created using multiple data sets to observe all relevant uncertainties in the system. The Discrete Extended Kalman Filter is used as an identification/parameter estimation method for each data set, in addition to providing a covariance matrix which aids in the development of the uncertainty model. Once ground based modal uncertainties have been developed, they are localized to specific degrees of freedom in the form of mass and stiffness uncertainties. Two techniques are presented: a matrix method which develops the mass and stiffness uncertainties in a mathematical manner; and a sensitivity method which assumes a form for the mass and stiffness uncertainties in macroelements and scaling factors. This form allows the derivation of mass and stiffness uncertainties in a more physical manner. The mass and stiffness uncertainties of the ground based system are then mapped onto the on-orbit system, and projected to create an analogous on-orbit uncertainty model in the form of mean errors and bounds on critical parameters. The Middeck Active Control Experiment is introduced as experimental verification for the localization and projection methods developed. In addition, closed loop results from on-orbit operations of the experiment verify the use of the uncertainty model for control analysis and synthesis in space.

Campbell, Mark E.; Crawley, Edward F.

1996-01-01

322

QUANTITATIVE RISK ANALYSIS: DETERMINING UNIVERSITY RISK MITIGATION AND CONTROL MECHANISMS  

Directory of Open Access Journals (Sweden)

Full Text Available The paper seeks to examine adequacy of risk mitigation mechanisms by using methodologies derived from quantitative risk analysis in a University context. A questionnaire and an interview schedule were administered. The researchers used ‘risk modal’ responses model for the evaluation of the adequacy of risk mitigation. Furthermore, the researchers incorporated expert judgements, binomial distribution model and one way-repeated measure ANOVA into the risk mitigation analysis. The first category of findings revealed that (1 the University has no adequate control mechanisms to mitigate risk (2 the University does not take adequate account of key risks identified by key stakeholders and thirdly (3 the University’s overall approach to risk management, as assessed for one-academic year is not adequate for its strategic objectives. The second category from general perspective suggested there was a significant relationship between individual key risks been assigned to appropriate managers and risk mitigation. Moreover, there was good reason to suggest a relationship between various committees taking adequate account of key risks identified by key stakeholders and risk mitigation. Lastly the results revealed that there was enough evidence supporting a relationship between institution's overall approach to risk management, and its strategic objectives on risk mitigation.

Anass BAYAGA

2010-06-01

323

Numerical stability analysis in respiratory control system models  

Directory of Open Access Journals (Sweden)

Full Text Available Stability of the unique equilibrium in two mathematical models (based on chemical balance dynamics of human respiration is examined using numerical methods. Due to the transport delays in the respiratory control system these models are governed by delay differential equations. First, a simplified two-state model with one delay is considered, then a five-state model with four delays (where the application of numerical methods is essential is investigated. In particular, software is developed to perform linearized stability analysis and simulations of the model equations. Furthermore, the Matlab package DDE-BIFTOOL v.~2.00 is employed to carry out numerical bifurcation analysis. Our main goal is to study the effects of transport delays on the stability of the model equations. Critical values of the transport delays (i.e., where Hopf bifurcations occur are determined, and stable periodic solutions are found as the delays pass their critical values. The numerical findings are in good agreement with analytic results obtained earlier for the two-state model.

Laszlo E. Kollar

2005-04-01

324

Is there a place for hair analysis in doping controls?  

Science.gov (United States)

The actual antidoping control rules applied in sports (as established by the International Olympic Committee and the International Sport Federations) state that a positive case is chemically established by the unequivocal detection of a forbidden parent molecule and/or any of its metabolite(s) in urine, no matter the amounts which were administered and when the drug was taken. Screening is accomplished most of the time by using GC-MS procedures. These have been optimized to detect most if not all of the forbidden compounds which are put on a list. Recently, attempts have been made on scalp hair to demonstrate the value of this matrix as a possible means for differentiating between therapeutic use and doping abuse. In particular, GC-mass selective detector and GC-high resolution MS were successfully applied to treated animals and body-builders for anabolic agents (steroids and beta-2-agonists) at high sensitivity detection (low ng/g level). Naturally occurring molecules, like testosterone and its metabolites, could also be differentiated from their synthetic counterparts. Positive cases are more often challenged in courts and retrospectivity in time of the drug(s) intake is becoming an important issue for evaluating the responsibility of the person. This is can be based on hair analyses if the drugs have been taken at regular intervals. Stimulants and narcotics are often used in sports like drug of abuse in the ordinary social contexts. On the other hand, anabolic agents, when taken to improve the physical performances, follow complex regimens with the mixing of various formulas and dosages. Scalp hair references ranges for these as well as for endogenous substances still wait to be established statistically for competing, well-trained athletes. The incorporation rate into blond or gray hair is poorer than that of dark colored hair raising the question of individuals equality against the controls, a very important matter of concern for the sport's governing bodies. The frequency of hair cutting and short hair cuts necessary to gain speed in specific sports like swimming are other critical factors. On the other hands, irregular hair growth, associated with the washout effect through multiple washing and staining processes over expanded time intervals can cause concentrating or diluting effects. So far, a minority of prohibited substances could be detected in scalp hair with the sensitivity and specificity required in the context of the sport's activities. From the above, clear limitations of the usefulness of hair analysis in doping control analysis are obvious until a lot more data relevant to this particular field have been collected. PMID:10689583

Rivier, L

2000-01-10

325

Genetic analysis of rice varietal diversity for rice blast control.  

Science.gov (United States)

Two Indica hybrid rice of Shanyou63 (A) and Shanyou22 (B), two glutinous landraces of Huanghenuo (C) and Zinuo (D) and three improved Japonica rice of Hexi41 (E), Chujing12 (F) and 8126 (G) were selected and their genetic resistance relationship was estimated using resistance gene analogue (RGA). The results showed that there were similar genetic relationships between hybrid varieties at the genetic similarity (GS) of 0.86,and among improved Japonica varieties at the GS of 0.84, while highly genetic diversifications between traditional varieties, Indica and Japonica varieties, traditional and modern variety ( GS:0.45). The results also showed that clustering analysis based on RGA data were generally corresponded to known pedigrees and blast field resistances of the varieties. Based on varietal differences in RGA data and agronomic traits, plot experiments of five mixed-planting combinations of A/C, A/D, B/C, B/D and A/B and two combinations of E/C and E/F/G were conducted in Jianshui and Shiping counties ( Indica rice growing region) and Luxi County (warm Japonica region) in Yunnan Province in past two years, respectively. The results demonstrated that rice blast management was more effective in five mixed-planting combinations of varieties with different genetic backgrounds (GS: 0.45-0.77) than in two combinations with similar genetic relationships (GS: 0.84-0.90), compared with their monocultures. It is evident for the highly susceptible landraces in mixed-planting to achieve disease control, with significant decreases both in incidence and severity. The blast control efficiencies of landraces in different mixture combinations reached to 54.47%-92.18%. The control efficiencies of improved varieties varied from 15.12% to 25.54% in mixture combinations with closed genetic relationship. In addition,the total yield of 5 varietal combinations with distant genetic relationship increased 539.0-904.0 kg/ha in the mixed-planting plots, at increase rates of 5.6%-10.2%. Mixed rice varieties with similar genetic background did not achieve significant yield increase. Otherwise, the yield of E/F/G decreased 2.7%-4.0% compared with pure stand. The results can provide scientific basis of varietal combinations in diversification experiments for blast control. PMID:15473323

Zhu, You-Yong; Sun, Yan; Wang, Yun-Yue; Li, Yan; He, Yue-Qiu; He, Xia-Hong; Mundt, Christopher C; Mew, Tom W; Hei, Leung

2004-07-01

326

Energy transfer from Eu{sup 2+} to Mn{sup 2+} in M{sub 5}(PO{sub 4}){sub 3}Cl (M=Ca, Sr)  

Energy Technology Data Exchange (ETDEWEB)

M{sub 4.95?y}(PO{sub 4}){sub 3}Cl:0.05Eu{sup 2+}, yMn{sup 2+} (M=Ca, Sr) phosphors were synthesized at 1200 °C under a reductive atmosphere. The energy transfer mechanism and efficiency (?) from Eu{sup 2+} to Mn{sup 2+} as well as the quantum efficiency (Q) of the Mn{sup 2+} emission were analyzed using PL spectra and decay curves. Least squares fittings of the Eu{sup 2+} decay curves indicate that the energy transfer from Eu{sup 2+} to Mn{sup 2+} follows the exchange mechanism in the Sr system, while besides exchange mechanism other complicated quenching processes are involved in the Ca system. Superficially the ? is high but the Q is low, which implies some energy loss. Two quenching models representative of an “inverse bottleneck process”, which is related to the lifetime mismatch between Eu{sup 2+} and Mn{sup 2+}, and a “charge transfer process“ in the Eu{sup 2+}–Mn{sup 2+} clusters, are proposed. The results may provide some clues for designing excellent sensitizer and activator co-doped phosphors in our further work. -- Highlights: • Energy transfer efficiency of Eu{sup 2+} is high and the emission efficiency of Mn{sup 2+} is low. • Inverse bottleneck effect related to Eu{sup 2+}/Mn{sup 2+} lifetime mismatch causes quenching. • Charge transfer process in Eu{sup 2+}–Mn{sup 2+} clusters also causes quenching.

Yang, Fengli [National Engineering Research Center for Rare Earth Materials, General Research Institute for Nonferrous Metals, and Grirem Advanced Materials Co. Ltd., Beijing 100088 (China); Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou, Jiangxi 341000 (China); An, Wei [School of Physics, Peking University, Beijing 100871 (China); Zhuang, Weidong, E-mail: wdzhuang@126.com [National Engineering Research Center for Rare Earth Materials, General Research Institute for Nonferrous Metals, and Grirem Advanced Materials Co. Ltd., Beijing 100088 (China); Tian, Guang-Shan [School of Physics, Peking University, Beijing 100871 (China); Jing, Xi-Ping, E-mail: xpjing@pku.edu.cn [Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

2014-02-15

327

Stability Analysis and Control of Nonlinear Phenomena in Buck Converters Using Variable Structure Control Approach  

Directory of Open Access Journals (Sweden)

Full Text Available The time varying, nonlinear nature of the power switches and several other sources of nonlinearities in DC-DC Converters deviates its performance from the theoretical prediction of stability. The switching nature necessitates a study of the stability and their periodic orbit rather than the equilibrium point. The closed loopoperation exhibits several types of nonlinear phenomena including bifurcation, chaos and quasi-periodicity. This paper is oriented with the analysis of such nonlinear phenomena in buck converter and attempts to coin a new strategy that can control chaos and significantly extend the parameter range for nominal period-I operation, in its mission to enhance the operating range of the converter.

Dr. S. R. PARANJOTHI,

2011-01-01

328

Experimental Analysis of Autostratigraphic Controls in Foreland Basins  

Science.gov (United States)

Understanding the relation between sedimentation and tectonic pulses in foreland basins is the key to and adequate analysis of the evolution of morphodynamics and basin stratigraphic architecture, which is also a requirement for adequate exploration and production of fossil fuels. Several models have been proposed to explain this relationship and help revealing basin development in natural systems. However all these models work under the assumption that an steady allogenic forcing will produce a steady stratigraphic signature and do not account for the autostratigraphic behavior of these systems, that is, the inherent behavior due to unique geometry of the basin subsidence. We present flume tank experiments that aim to explore the autostratigraphic controls asserted over foreland basin type subsidence. With these experiments and the accompanying mathematical model we have identified three different modes in the fill of a foreland basin. Our analysis indicated that the three modes are basic inherent autostratigraphic, and dependent on the ratio between the back-tilting subsidence (typical of these basins) rate and the sediment supply to the basin. The first autostratigraphic behavior is the already known "autoretreat", during which the shoreline goes from progradation to an eventual retrogradation. The second presents an initial progradation followed by a constant aggradation. And finally the model shown a new behavior named "autoaccelerated progradation" in which the progradation is maintained during the whole evolution, but is accelerated after a certain point. The autostratigraphic evolution shown in this experimental work even though it is simplified compared to real-world examples will give an insight that allows the development of a more accurate basin fill model for retroarc foreland basins.

Leva Lopez, J.; Kim, W.; Steel, R. J.

2011-12-01

329

Analysis for Secondary Task in Advanced Main Control Room Using Soft Controls  

International Nuclear Information System (INIS)

The purpose of this study is to analyze operator tasks using soft controls from the simulation data of an advanced MCR. In this study, the primary and secondary tasks of eighteen simulation data were analyzed. The results showed that secondary tasks were required to perform scenarios more than primary task needs. Among these secondary tasks, the 'switch screen' made up the largest portion. This indicates that operator workload would increase with an increase of the 'switch screen' task. To reduce operator workload, Cps designers put the screen link buttons in the Cps. According to an analysis of secondary tasks using the screen link buttons, it is recognized that using the screen link buttons of the Cps helps reduce the number of secondary tasks and reduce errors of the 'switch screen'. Therefore, although increased secondary tasks can affect the increase of operator workload according to the adapting soft controls in advanced MCRs, using supporting designs such as the screen link buttons helps to reduce operator workload and errors

330

Quantitative analysis of distributed control paradigms of robot swarms  

DEFF Research Database (Denmark)

Given a task of designing controller for mobile robots in swarms, one might wonder which distributed control paradigms should be selected. Until now, paradigms of robot controllers have been within either behaviour based control or neural network based control, which have been recognized as two mainstreams of controller design for mobile robots. However, in swarm robotics, it is not clear how to determine control paradigms. In this paper we study the two control paradigms with various experiments of swarm aggregation. First, we introduce the two control paradigms for mobile robots. Second, we describe the physical and simulated robots, experiment scenario, and experiment setup. Third, we present our robot controllers based on behaviour based and neural network based paradigms. Fourth, we graphically show their experiment results and quantitatively analyse the results in comparison of the two methods. Closing remarks conclude the paper.

Ngo, Trung Dung

2010-01-01

331

Integrated Model Reduction and Control of Aircraft with Flexible Wings  

Science.gov (United States)

This paper presents an integrated approach to the modeling and control of aircraft with exible wings. The coupled aircraft rigid body dynamics with a high-order elastic wing model can be represented in a nite dimensional state-space form. Given a set of desired output covariance, a model reduction process is performed by using the weighted Modal Cost Analysis (MCA). A dynamic output feedback controller, which is designed based on the reduced-order model, is developed by utilizing output covariance constraint (OCC) algorithm, and the resulting OCC design weighting matrix is used for the next iteration of the weighted cost analysis. This controller is then validated for full-order evaluation model to ensure that the aircraft's handling qualities are met and the uttering motion of the wings suppressed. An iterative algorithm is developed in CONDUIT environment to realize the integration of model reduction and controller design. The proposed integrated approach is applied to NASA Generic Transport Model (GTM) for demonstration.

Swei, Sean Shan-Min; Zhu, Guoming G.; Nguyen, Nhan T.

2013-01-01

332

Novel analysis of Petri-net-based controllers by means of TCT implementation tool of supervisory control theory  

Directory of Open Access Journals (Sweden)

Full Text Available The control of discrete event systems (DES has been widely studied in the past two decades. Finite-state automata (FSA and Petri nets (PN are the two principal modelling formalisms for this study. Supervisory control theory (SCT, based on language and FSA concepts, is a well established framework for the study of discrete event control systems (DECS. PN-based approaches to the control design have been considered as an alternative framework. In the PN-based control of DES, given an uncontrolled PN model of a system and a set of specifications, a PN-based controller consisting of monitors (control places is synthesised to solve the problem. In general, forbidden-state specifications are considered. Another heavily studied specification is to obtain the live system behaviour (non-blockingness in SCT terminology for a given PN model by computing a PN-based controller. Unfortunately, PN-based analysis tools cannot deal with uncontrollable transitions. Therefore, to date there is no general technique for the correctness analysis of the computed PN-based controllers. This paper proposes a novel and general methodology to carry out the correctness analysis for the computed PN-based controllers by using the TCT implementation tool of SCT. Three examples are considered for illustration.

Murat Uzam

2010-09-01

333

Performance Analysis Of Shunt Active Filter Using Different Controllers  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, Performance of Shunt active power filter (SAPF is analyzed for various types of non linear loads. Among the various control schemes available for SAPF, indirect current control scheme is used here. PI controller and fuzzy logic controller are used to analyze its performance for various types of nonlinear loads (R, DC motor, Induction motor. The output parameters are Total Harmonic Distortion (THD and power factor. The results are obtained with the conventional PI controller and fuzzy controller. The proposed method offer an efficient control method under the various load conditions results in power factor improvement and THD reduction. Simulation of the proposed controller(PI and fuzzy logic controller of a shunt active power filter has been carried out in MATLAB/SIMULINK and the aim is to reduce the THD and improve the power factor.

K.Sarasvathi#1 , R.Rajalakshmi#2 , Member, IEEE

2013-05-01

334

Fuzzy Current-Mode Control and Stability Analysis  

Science.gov (United States)

In this paper a current-mode control (CMC) methodology is developed for a buck converter by using a fuzzy logic controller. Conventional CMC methodologies are based on lead-lag compensation with voltage and inductor current feedback. In this paper the converter lead-lag compensation will be substituted with a fuzzy controller. A small-signal model of the fuzzy controller will also be developed in order to examine the stability properties of this buck converter control system. The paper develops an analytical approach, introducing fuzzy control into the area of CMC.

Kopasakis, George

2000-01-01

335

Analysis of Fuzzy PID and Immune PID Controller for Three Tank Liquid Level Control  

Directory of Open Access Journals (Sweden)

Full Text Available In industrial control systems the liquid level iscarrying its significance as the control action for level control intanks containing different chemicals or mixtures is essential forfurther control linking set points. The three level control modelsare considered in our work. The conventional control algorithm isdifficult to reach required control quality with more strictrestriction on overshoot. Design a parameter self-tuningPID-controller based on fuzzy control, which can adjustPID-parameters according to error and change in error.Biological immune system is a control system that has strongrobusticity and self-adaptability in complex disturbance andindeterminacy environments. The artificial intelligence techniqueof fuzzy logic and immune controller is adopted for more reliableand precise control action which incorporate the uncertain factorsalso. In this work the comparison of the conventional model, fuzzymodel and immune feedback mechanism is clarified.

Sharad Kumar Tiwari

2011-09-01

336

The changing role of Material Control and Accountability at Savannah River Site  

Energy Technology Data Exchange (ETDEWEB)

As Westinghouse Savannah River Company has been faced with the challenge of better meeting DOE needs with reduced budgets and manpower, the Materials Control and Accountability (MC&A) organization has taken a hard look at its roles and responsibilities. A MC&A program is composed of many functions that can not only meet safeguards needs, but can be used by several organizations across the site to meet their needs as well. These functions include nuclear material measurements, tracking, accounting, and inventory control. The infrastructure in place to provide these functions for accountable nuclear materials requires only a few adjustments to expand to other areas of nuclear materials accounting and control. By integrating several organizations` requirements, the MC&A section can allow line organizations to reduce their costs and rely on the section to better service their needs. On the reverse side, MC&A has completed several cost reduction measures that will allow it to expand its role with no increased costs. The roles and responsibilities of the nuclear material control and accountability program should be expanded. The program`s existing information infrastructure, and knowledge and experience in nuclear material measurements and safeguards can be built upon to meet the needs of new areas such as waste management and decommissioning and decontamination while continuing to support the existing processing. and storage efforts of current facilities.

Rodriguez, M.P.

1994-07-01

337

A new microcomputer-controlled neutron activation and analysis system. Description and applications for the analysis of bioenvironmental specimens.  

Science.gov (United States)

A microcomputer-controlled irradiation and measurement system and a microprocessor-controlled sample changer have been installed at the SLOWPOKE-2 Facility at the Royal Military College of Canada (RMC). These systems can provide the gamut of instrumental neutron activation analysis (INAA) techniques for the analyst. Custom software has been created for system control, data acquisition, and off-line spectral analysis using programs that incorporate Gaussian peak-fitting methods of analysis. The design and use of the equipment is discussed, and the performance is illustrated with results obtained from the analysis of marine sediment and biological reference materials. PMID:1704760

Edward, J B; Beeley, P A; Bennett, L G; Poland, J S

1990-01-01

338

Fast neutron activation analysis and radioisotope X-ray fluorescence study on KALEWA and NAMMA coal  

International Nuclear Information System (INIS)

Kalewa coal was studied with Fast Neutron Activation Analysis (FNAA) technique, employing KAMAN A-710 neutron generator and HP(Ge) detector coupled to ''Canberra'' series 30 MCA. Sequential irradiation and dual aluminium foil monitoring method was employed. Simultaneous multielement analysis was carried out. Namma Coal was studied with radioisotope X-ray Fluorescence (XRF) technique, employing Co-57 exciter source and HP(Ge) detector coupled to ''Canberra'' series 40 MCA. In both FNAA and XRF study, the results obtained were compared to that obtained with Atomic Absorption Spectrophotometry (AAS) technique. Finally, the results were reviewed together with those obtained from similar work on coal with FNAA and XRF techniques. (author)

339

Direct Torque Control in presence of Current sensor failure in Variable Speed Wind System: Effect analysis, detection and control reconfiguration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a study of current sensor failure in a Direct Torque Control applied to a Double Fed Induction Generator based Variable Speed Wind System. The effect of scaling and offset current sensor errors is discussed through sensibility analysis. A control reconfiguration is then proposed to remedy this sensor failure. Simulation results emphasize the good performances of the proposed current sensor fault tolerant control

Arbi, A. J.; Slama-belkhodja, I.

2008-01-01

340

Next Generation Nuclear Plant Resilient Control System Functional Analysis  

International Nuclear Information System (INIS)

Control Systems and their associated instrumentation must meet reliability, availability, maintainability, and resiliency criteria in order for high temperature gas-cooled reactors (HTGRs) to be economically competitive. Research, perhaps requiring several years, may be needed to develop control systems to support plant availability and resiliency. This report functionally analyzes the gaps between traditional and resilient control systems as applicable to HTGRs, which includes the Next Generation Nuclear Plant; defines resilient controls; assesses the current state of both traditional and resilient control systems; and documents the functional gaps existing between these two controls approaches as applicable to HTGRs. This report supports the development of an overall strategy for applying resilient controls to HTGRs by showing that control systems with adequate levels of resilience perform at higher levels, respond more quickly to disturbances, increase operational efficiency, and increase public protection.

 
 
 
 
341

Next Generation Nuclear Plant Resilient Control System Functional Analysis  

Energy Technology Data Exchange (ETDEWEB)

Control Systems and their associated instrumentation must meet reliability, availability, maintainability, and resiliency criteria in order for high temperature gas-cooled reactors (HTGRs) to be economically competitive. Research, perhaps requiring several years, may be needed to develop control systems to support plant availability and resiliency. This report functionally analyzes the gaps between traditional and resilient control systems as applicable to HTGRs, which includes the Next Generation Nuclear Plant; defines resilient controls; assesses the current state of both traditional and resilient control systems; and documents the functional gaps existing between these two controls approaches as applicable to HTGRs. This report supports the development of an overall strategy for applying resilient controls to HTGRs by showing that control systems with adequate levels of resilience perform at higher levels, respond more quickly to disturbances, increase operational efficiency, and increase public protection.

Lynne M. Stevens

2010-07-01

342

EFFICIENCY ANALYSIS OF THE LIQUID CONTROLLER WITH A  

Directory of Open Access Journals (Sweden)

Full Text Available This paperwork studies the efficiency of the liquid controllers with a ring valve analysing the liquidrunning through the controller, the variation of the pressure and its speed for various forms of the ring valvecontroller.

BEAZIT Ali

2012-05-01

343

Analysis and design of controllers for a double inverted pendulum  

DEFF Research Database (Denmark)

A physical control problem is studied with the ? methodology. The issues of modelling, uncertainty modelling, performance specification, controller design and laboratory implementation are discussed. The laboratory experiment is a double inverted pendulum placed on a cart. The limitations in the system with respect to performance are the limitation in the control signal and the limitation of the movement of the chart. It is shown how these performance limitation will effect the design of a ? controller for the system.

Niemann, Hans Henrik

2003-01-01

344

Cost effectiveness analysis of optimal control measures for tuberculosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We propose and analyse an optimal control problem where the control system is a mathematical model for tuberculosis that considers reinfection. The control functions represent the fraction of early latent and persistent latent individuals that are treated. Our aim is to study how these control measures should be implemented, for a certain time period, in order to reduce the number of active infected individuals, while minimizing the interventions implementation costs. The op...

Rodrigues, Paula; Silva, Cristiana J.; Torres, Delfim F. M.

2014-01-01

345

Design and Analysis of Generalized Predictive Control for Moisture Content Control in a Benchmark Paper Plant  

Directory of Open Access Journals (Sweden)

Full Text Available The role of advanced control techniques for an energy intensive chemical process like paper industries is indispensable. The quality of the end product depends entirely on the efficiency and disturbance managing capacity of the control techniques. In this background the role of Model predictive control as a constraint handling as well as quality assuring tool has to be studied. In this study, two different model predictive controller techniques namely Dynamic Matrix Control (DMC and Generalized Predictive Controller (GPC is considered. The controllers are suitably designed for controlling the moisture level for a bench marked paper machine model. The servo performance of the DMC and GPC controllers under unconstrained environment is studied for and the results are tabulated in this study. The study reveals that the Dynamic matrix controller (DMC provides better performance than the Generalized Predictive Controller (GPC.

M. Sainabha

2014-01-01

346

Analysis of AP1000 reactor power control system  

International Nuclear Information System (INIS)

The reactor power control modes applied by common nuclear power plants and AP1000 is introduced briefly. The advantages and shortcomings are compared and summarized. Advice is also made to the control strategy of the first and continued SMNPC plants. Additionally, the characteristics of the AP1000 reactor control system are summarized and problems which the operators will probably encounter are also analyzed. (authors)

347

Network analysis reveals multiscale controls on streamwater chemistry  

Science.gov (United States)

By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in an entire fifth-order stream network. These samples were analyzed for an exhaustive suite of chemical constituents. The fine grain and broad extent of this study design allowed us to quantify spatial patterns over a range of scales by using empirical semivariograms that explicitly incorporated network topology. Here, we show that spatial structure, as determined by the characteristic shape of the semivariograms, differed both among chemical constituents and by spatial relationship (flow-connected, flow-unconnected, or Euclidean). Spatial structure was apparent at either a single scale or at multiple nested scales, suggesting separate processes operating simultaneously within the stream network and surrounding terrestrial landscape. Expected patterns of spatial dependence for flow-connected relationships (e.g., increasing homogeneity with downstream distance) occurred for some chemical constituents (e.g., dissolved organic carbon, sulfate, and aluminum) but not for others (e.g., nitrate, sodium). By comparing semivariograms for the different chemical constituents and spatial relationships, we were able to separate effects on streamwater chemistry of (i) fine-scale versus broad-scale processes and (ii) in-stream processes versus landscape controls. These findings provide insight on the hierarchical scaling of local, longitudinal, and landscape processes that drive biogeochemical patterns in stream networks.

McGuire, Kevin J.; Torgersen, Christian E.; Likens, Gene E.; Buso, Donald C.; Lowe, Winsor H.; Bailey, Scott W.

2014-01-01

348

Analysis and Control of Flora in Cream Vegetarian Salad  

Directory of Open Access Journals (Sweden)

Full Text Available A survey of microbial pollution and health quality change was conducted during the process of the production and refrigeration of Cream Vegetarian Salad food, to provide a basic reference for the catering industry to carry out HACCP management system for food like this and ensure the safety of food. Then a basic formula of Cream Vegetarian Salad was made according to the literature, further the total number of bacteria, pseudomonas, lactic acid bacteria, enterobacter, cocci and microzyme was tested in the main raw material and finished product detection according to the national standard method, Without changing the taste of the finished production, the raw materials were blanched, to measure the reduced bacteria rate, and determine the improved formula; the salad was stored at 4°C, then the number of bacteria was counted according to the time sequence and flora analysis was made to draw up the date of minimum durability. The total bacterial count of the Cream Vegetarian Salad by the basic formula is 2.3×104 CFU/g, among which coriander occupies 87%, sweetbell 7%, the rest is of small scale. Thus, the Cream Vegetarian Salad made in kitchen can be seriously polluted by microbial, mainly due to parsley, sweetbell red pepper and other raw materials, through the method of sterilization, storage in low temperature secondary pollution can be avoided, and the bacterial count can be controlled effectively, then the shelf life was extended and the risk of food poisoning was reduced, which did a lot of benefit to the food safety management of the catering industry.

Yang Yuan

2014-02-01

349

Analysis and Control of Bulgaria Onion Cold Soup  

Directory of Open Access Journals (Sweden)

Full Text Available A survey of microbial pollution and health quality change was conducted during the process of the production and refrigeration of Onion Cold Soup to provide a basic reference for the catering industry for the implementation of HACCP management system for food and to ensure the safety of food. A basic formula of Onion Cold Soup was made according to the literature, then the total number of bacteria, pseudomonas, lactic acid bacteria, enterobacter, cocci and microzyme were tested in the main raw material and finished product detection according to the national standard method; hot boiling water to wash the main raw materials, statistical reduction in strain rate, in order to determine improvement formula. The finished cold soup at 4°C refrigerator made flora analysis, and drew up the date of minimum durability. The total bacterial count of the Onion Cold Soup by the basic formula is 2.4?104cfu/g, among which coriander occupied 53%, egg 24%, onion and lemonade 17% and 6%; respectively; and after blanching, the total number of colonies in the improved formulation is 1.1?103, the sterilization rate reaches 95.4%, and the effect is slightly obvious. The Onion Cold Soup made in kitchen can be seriously polluted by microbial, hot boiling water to wash the main raw materials and avoid secondary pollution, thus the bacterial count can be controlled effectively, then the shelf life was extended and the risk of food poisoning was reduced, which did a lot of benefit to the catering industry the food safety management.

Yunsheng Jiang

2014-02-01

350

Screening of conditions controlling spectrophotometric sequential injection analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Despite its potential benefits over univariate, chemometrics is rarely utilized for optimizing sequential injection analysis (SIA methods. Specifically, in previous vis-spectrophotometric SIA methods, chemometrically optimized conditions were confined within flow rate and reagent concentrations while other conditions were ignored. Results The current manuscript reports, for the first time, a comprehensive screening of conditions controlling vis-spectrophotometric SIA. A new diclofenac assay method was adopted. The method was based on oxidizing diclofenac by permanganate (a major reagent with sulfuric acid (a minor reagent. The reaction produced a spectrophotometrically detectable diclofenac form. The 26 full-factorial design was utilized to study the effect of volumes of reagents and sample, in addition to flow rate and concentrations of reagents. The main effects and all interaction order effects on method performance, i.e. namely sensitivity, rapidity and reagent consumption, were determined. The method was validated and applied to pharmaceutical formulations (tablets, injection and gel. Conclusions Despite 64 experiments those conducted in the current study were cumbersome, the results obtained would reduce effort and time when developing similar SIA methods in the future. It is recommended to critically optimize effective and interacting conditions using other such optimization tools as fractional-factorial design, response surface and simplex, rather than full-factorial design that used at an initial optimization stage. In vis-spectrophotometric SIA methods those involve developing reactions with two reagents (major and minor, conditions affecting method performance are in the following order: sample volume > flow rate ? major reagent concentration >> major reagent volume ? minor reagent concentration >> minor reagent volume.

Idris Abubakr M

2011-02-01

351

Design and Analysis of a Sliding Table Controller for Diabetes  

Directory of Open Access Journals (Sweden)

Full Text Available A discrete insulin infusion based on long-time interval measurement is the classic technique for diabetes treatment. Nevertheless, in this research, a closed-loop control system was proposed for continuous drug infusion to overcome the drawbacks of these typical discrete methods and develop more practical diabetes therapy systems. A blood glucose-insulin system was implemented relying on continuous insulin injection model. Based on this model, two controllers were designed to deal with the control dilemma of the resulting highly nonlinear plant. The controllers designed in this paper are: proportional integral derivative (PID, and sliding table controllers. Simulation results have shown that the sliding table controller can outperform the PID controller even with severe circumstances of disturbance in glucose, such as exercise, delay or noise in glucose sensor and nutrition mixed meal absorption at meal times.

Ahmed Y. Ben Sasi

2013-08-01

352

Operational analysis and limitations of the VSI-Based multi-line FACTS controllers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, the operational analysis and the main limitations of the VSI-based multi-line FACTS controllers, namely: the GIPFC (Generalized Interline Power Flow Controller) and the IPFC (Interline Power Flow Controller), are analyzed. The GIPFC & IPFC are amongst the newest devices within the FACTS technology. By utilizing these devices an enhanced and nearly instantaneous controllability over independent transmission systems, can be obtained. The steady-state analysis of a GIPFC & IPFC co...

2006-01-01

353

Simulation of the treat-upgrade automatic reactor control system  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the design of the Automatic Reactor Control System (ARCS) for the Transient Reactor Test Facility (TREAT) Upgrade. A simulation was used to facilitate the ARCS design, and to completely test and verify its operation before installation at the TREAT facility. The ARCS is a microprocessor network based closed loop control system that provides a position demand control signal to the transient rod hydraulic drive system. There are four identical servo-hydraulic rod drives and each operates as a position control system. The ARCS updates its position demand control signal every 1 msec and its function is to control the transient rods so that the reactor follows a prescribed power-time profile (planned transient). The Main Control Algorithm (MCA) for the ARCS is an optimal reactivity demand algorithm. At each time step, the MCA generates a set of reference reactor functions, e.g., power, period, energy, and delayed neutron power. These functions are compared to plant measurements and estimated values at each time step and are operated on by appropriate algorithms to generate the reactivity demand function. The data necessary to calculate the reference functions is supplied from a Transient Prescription Control Data Set (TPCDS). The TPCDS specifies the planned transient as a fixed number of simply connected independent power profile segments. The developed simulation code models the TREAT reactor kinetics, the hydraulic rod drive system, the plant measurement system, and the ARCS control processor MCA. All of the models operate as continuous systems with the exception of the MCA which operates as a discrete time system at fixed multiples of 1 msec. The study indicates that the ARCS will meet or exceed all of its design specifications.

Lipinski, W.C.; Kirsch, L.W.; Valente, A.D.

1985-02-01

354

Molecular analysis of the genera eremopyrum (ledeb). jaub. and spach and agropyron gaertner (poaceae) by pcr methods  

International Nuclear Information System (INIS)

RAPD-PCR (Random Amplified Polymorphic DNA Polymerase Chain Reaction) and Post PCR (Polymerase Chain Reaction) Melting Curve Analysis (MCA) have been used to investigate the pattern of genetic variation among some species in the genera Eremopyrum (Ledeb.) Jaub. and Spach and Agropyron Gaertner (Poaceae). Thirteen primers have been used in the study based on the RAPD-PCR and MCA analyses. Each species produced a distinct pattern of DNA fragments which have been used as a measure of the degree of relationship between species by means of using the RAPD-PCR results with three primers selected for identifying the genetic similarities. Polymorphic melting profiles have been obtained with Post PCR MCA method using three primers. Genetic similarities are calculated for all the species studied with RAPD-PCR and MCA methods, the dendrograms are obtained with the MVSP (Multi Variate Statistical Package) software using UPGMA (Unweighted Pair Group Method with Arithmetic Averages) and Jaccard's Coefficient. Polymorphism between 18 populations of Eremopyrum and 6 Agropyron populations and within the species are determined by using RAPD-PCR and Post PCR melting curve analysis (MCA) respectively. (author)

355

Control of interferences in the analysis of low-concentration I 129  

International Nuclear Information System (INIS)

Traces of uranium, cesium and tellurium interfere in the determination of I 129 by neutron activation analysis. The paper describes the procedures used to control or eliminate the interferences in the different steps of the analysis

356

Analysis and design of controllers for a double inverted pendulum  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A physical control problem is studied with the ? methodology. The issues of modelling, uncertainty modelling, performance specification, controller design and laboratory implementation are discussed. The laboratory experiment is a double inverted pendulum placed on a cart. The limitations in the system with respect to performance are the limitation in the control signal and the limitation of the movement of the chart. It is shown how these performance limitation will effect the design of a ?...

Niemann, Hans Henrik; Poulsen, J. K.

2010-01-01

357

Simulation Based Analysis of Two Different Control Strategies for PMSM  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In low power application generally permanent magnet synchronous motor (PMSM) are used. Because of their high performance/cost ratio, the attention toward PMSM in variable speed application, is greater. Control of torque, rotation speed and position for four quadrants and low speed operation, with high-performance dynamic behaviour, are often required in industrial applications but they are sensitive from the standpoint of the control strategies reliability. Vector control based on fieldorient...

Lindita Dhamo, Aida Spahiu

2013-01-01

358

Control, stability analysis and grid integration of wind turbines.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In Chapters 2 and 3 of the thesis we propose a self-scheduled control method for a doublyfed induction generator driven by a wind turbine (DFIGWT), whose rotor is connected to the power grid via two back-to-back PWM power converters. We design a controller for this system using the linear matrix inequality based approach to linear parameter varying (LPV) systems, which takes into account the nonlinear dynamics of the system. We propose a two-loop hierarchical control structure....

Wang, Chen

2008-01-01

359

Designing operational control architectures of critical systems by reachability analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a method that eases the design of the operational architecture of a control system by providing, from the knowledge of some characteristics of the functions that the control system must ensure and a generic model of controller, an assignment solution of these functions that satisfies capabilities and distribution constraints. This method relies on the verification of a reachability property on a network of communicating automata that models the assignment process. The bene...

2011-01-01

360

Modeling of HCCI Engine Combustion for Control Analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Operation of homogeneous charge compression ignition (HCCI) enginesare very sensitive to timing variations in the combustion of theair-fuel charge mixture and require precise control of the ignitioninstant to run properly. It is therefore essential to understand thecharacteristics of timing variations under various operatingconditions in order to find suitable control strategies. This paperpresents a first step towards the construction of an HCCI enginemodel aimed at studies on timing control...

Bengtsson, Johan; Ga?fvert, Magnus; Strandh, Petter

2004-01-01

 
 
 
 
361

Design and analysis of controllers for a double inverted pendulum.  

Science.gov (United States)

A physical control problem is studied with the Hinfinity, and the micro methodology. The issues of modeling, uncertainty modeling, performance specification, controller design, and laboratory implementation are discussed. The laboratory experiment is a double inverted pendulum placed on a cart. The limitations in the system with respect to performance are the limitation in the control signal and the limitation of the movement of the cart. It is shown how these performance limitations will effect the design of Hinfinity and micro controllers for the system. PMID:15682623

Niemann, Henrik; Poulsen, Jesper Kildegaard

2005-01-01

362

Design and Analysis of Controllers for an Double Inverted Pendulum  

DEFF Research Database (Denmark)

A physical control problem is studied with the H_inf and the SSV methodology. The issues of modelling, uncertainty modelling, performance specification, controller design and laboratory implementation are discussed. The laboratory experiment is a double inverted pendulum placed on a cart. The limitations in the system with respect to performance are the limitation in the control signal and the limitation of the movement of the cart. It is shown how these performance limitations will effect the design of H_inf and SSV controllers for the system.

Niemann, Hans Henrik

2005-01-01

363

Simulation Based Analysis of Two Different Control Strategies for PMSM  

Directory of Open Access Journals (Sweden)

Full Text Available In low power application generally permanent magnet synchronous motor (PMSM are used. Because of their high performance/cost ratio, the attention toward PMSM in variable speed application, is greater. Control of torque, rotation speed and position for four quadrants and low speed operation, with high-performance dynamic behaviour, are often required in industrial applications but they are sensitive from the standpoint of the control strategies reliability. Vector control based on fieldoriented control (FOC is one of the methods most investigated and discussed by many researcher and now it is an industry standard. Traditional control methods based on FOC use position sensors result to be very expensive in electrical drive with low power. The aim of this paper is to show that sensorless control strategy based on MRAS approach can be applied successfully in PMSM drives with low cost. The results are obtained from comparison of two algorithms of vector control of PMSM: traditional FOC using position sensor and model reference adaptive system (MRAS approach based on sensorless vector control .Based on results obtained, advantages and disadvantages of the proposed control structures will be discussed.

Lindita Dhamo#1 , Aida Spahiu

2013-04-01

364

Stochastic analysis of dynamical systems with delayed control forces  

Science.gov (United States)

Reduction of structural vibration in actively controlled dynamical system is usually performed by means of convenient control forces dependent of the dynamic response. In this paper the existent studies will be extended to dynamical systems subjected to non-normal delta-correlated random process with delayed control forces. Taylor series expansion of the control forces has been introduced and the statistics of the dynamical response have been obtained by means of the extended Itô differential rule. Numerical application provided shows the capabilities of the proposed method to analyze stochastic dynamic systems with delayed actions under delta-correlated process contrasting statistics of response with estimates from Monte-Carlo (MC) simulation.

Pirrotta, A.; Zingales, M.

2006-07-01

365

An evaluation of cusum analysis and control charts applied to quantitative gamma-camera uniformity parameters for automated quality control  

Energy Technology Data Exchange (ETDEWEB)

Gamma-camera uniformity is often monitored for quality control of performance. Many parameters can be derived from computer analysis of the image of a uniform (flood) source to obtain quantitative measures of uniformity. To compare the various parameters and assess two techniques used for their analysis, a series of Tc-99m flood images were obtained consecutively. After establishing a baseline from repeated images, uniformity was degraded by offsetting the PHA window by a small amount. Nine non-uniformity parameters were calculated for each flood image and the uniformity index and the percentage of pixels more than 5% from the mean. All parameters were calculated for both central field-of-view (CFOV) and useful field-of-view (UFOV). Eighty such trials were carried out on two gamma-cameras. The PHA offsets ranged from 1-10 keV. The two techniques used for analysis were the control chart and cusum analysis. Decision levels were set for each parameter, as multiples of SD for the control charts or by varying the dimensions of a truncated V-mask for cusum analysis. Receiver operating characteristic (ROC) curves were then used for an objective comparison of the parameters and of the analysis techniques. The area under the ROC curve was used to rank the parameters in order of sensitivity to change in uniformity. The uniformity index and NEMA integral non-uniformity were found to be the most sensitive. Cusum analysis improved the sensitivity of those parameters that appeared to have low sensitivity to change when subjected to control chart analysis. However, there was little difference between the two analysis techniques for the more sensitive parameters. The ROC curves could also be used to provide a method for selecting decision levels, hence establishing an automated method for gamma-camera quality control. (orig.).

Knight, A.C.; Williams, E.D. (District General Hospital, Sunderland (United Kingdom). Regional Medical Physics Dept.)

1992-02-01

366

Analysis of control rod reactivity worths for AVR power plant at cold and hot conditions  

International Nuclear Information System (INIS)

The control rod worths of the AVR power plant for the cold and hot conditions were analyzed to verify an analysis method of reflector control rod worths. In the analysis method, the neutron-flux-weighting method was used to obtain the effective group constants of the control rod inserted in the graphite nose. The control rod worths were calculated with the core analysis code system for the High Temperature engineering Test Reactor (HTTR). The experimental values of the control rod worths were 6.47 and 6.81%?? for the cold and hot conditions, respectively. The differences between the experimental and analytical values for the cold and hot conditions were 2 and 10%, respectively. From these results, it was made clear that the analysis method applied here predicts well the control rod worth of the AVR power plant and is applicable for the nuclear designs of reflector control rods of future small HTGRs. (author)

367

Performance Analysis of Indirect Vector Control of Induction Motor Drive Using Fuzzy Logic Controller  

Directory of Open Access Journals (Sweden)

Full Text Available The induction motors were characterized by complex, highly non-linear and time-varying dynamics, and hence their promptness control is a stimulating problem in the engineering applications especially in high performance drive system. The fuzzy logic controller is found to be a very useful technique to obtain a high performance speed control. The present approach avoids the use of flux and speed sensor which increase the installation cost and mechanical robustness. The indirect vector controlled induction motor drives involve decoupling of the stator current in to torque and flux producing components. The comparative performance of Fuzzy Logic control technique has been presented and analyzed in this work. This paper based on the speed control of induction motor (IM using Fuzzy controller with the use of indirect vector control technique using MATLAB.

Dr.P.Nagasekhar Reddy

2014-04-01

368

POD a-posteriori error analysis for optimal control Problems with mixed control-state constraints  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this work linear-quadratic optimal control problems for parabolic equations with mixed control-state constraints are considered. These Problems arise when a Lavrentiev regularization is utilized for state constrained linear-quadratic optimal control problems. For the numerical solution a Galerkin discretization is applied utilizing proper orthogonal decomposition (POD). Based on a perturbation method it is determined how far the suboptimal control, computed on the basis of the POD method, ...

Gubisch, Martin; Volkwein, Stefan

2013-01-01

369

Analysis of three phase controlled rectifier with the same distance control as compared to the same angle control  

Directory of Open Access Journals (Sweden)

Full Text Available This research aim to compare the firing of the same distance and the same angle control at three phase controlled rectifier with seen generated harmonic at input (AC side. Then calculate of rectifier efficiency and power factor comparison from both the control type. The rectifier use passive filter with resistance 11 ohm and is analysed with program simulation using PSPICE version 7.1. Result of research indicate that use of the same distance control generates the 5th and 7th harmonics, while the same angle control generates the 3rd , 5th and 7th harmonics at the input (AC side. At the output (DC side, the same distance control type generates the 6th voltage ripples, while the same angle control generates the 2nd, and 6th voltage ripples. The result of calculation of voltage ripples that happened equal to 3.5% with efficiency 99.8% at same distance control, while at the same angle control obtained voltage ripples equal to 4% with efficiency 99.7% . At the firing angle 300 obtained by THD input equal to 50.26% with power factor equal to 0.89 at same distance control type, while the same angle control obtained by THD input equal to 53,831% with power factor to 0,87. From this result indicate that the firing of thyristor with the same distance better then is the same angle control.

Sudirman S

2007-11-01

370

Design and analysis of a gyroscopically controlled micro air vehicle  

Science.gov (United States)

Much of the current research on micro air vehicle design relies on aerodynamic forces for attitude control. The aerodynamic environment in which micro air vehicles operate is characterized by a low Reynolds number and is not fully understood, resulting in decreased performance and efficiency when compared to large-scale vehicles. In this work, we propose a new rotary-wing micro air vehicle design that utilizes gyroscopic dynamics for attitude control. Unlike traditional micro air vehicles where attitude control moments are generated by aerodynamic control surfaces, the proposed vehicle will leverage the existing angular momentum of its rotating components to generate gyroscopic moments for controlling attitude. We explore this paradigm in an effort to reduce mechanical complexity that is inherent in blade pitch modulation mechanisms such as the swashplate, and to increase agility and possibly even efficiency when compared to state-of-the-art micro vertical-take-off-and-landing vehicles. The evolution of the mechanical design, including the evaluation of three prototypes that explore the use of gyroscopic attitude control, is presented along with a comprehensive dynamic and aerodynamic model of the third prototype. Two controllers that utilize gyroscopic moments are developed and tested in simulation. In addition, several experiments were performed using a VICON motion tracking system and off-board control. These results will also be presented.

Thorne, Christopher Everett

371

The Revised Perceived Environmental Control Measure: A Review and Analysis.  

Science.gov (United States)

A study reveals the need for extensive refinement of the Revised Perceived Environmental Control Measure purported in the past to be a reliable and valid instrument to measure the relationship between the psychological construct, "locus of control," and environmental action or environmentally responsible behavior. (MCO)

Smith-Sebasto, N. J.

1992-01-01

372

Cost-effectiveness analysis of air-pollution control measures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We describe a strategy for dealing with the challenges of air pollution and climate change capable of adaptation to improved scientific knowledge in the future. The analytical framework for identifying efficient control strategies is described and selected results of cost-effective methods to control SO2, NOx and CO2 emissions are discussed.

Voß, Alfred; Schmid, Gu?nter

1991-01-01

373

Robust Control Analysis using Real-Time Implementation of a Hybrid Fuel Cell Power Generation System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper a complete robustness analysis is performed for a hybrid Fuel Cell/Supercapacitor generation system with power management, realized through the control of two identical boost power converters. For the closed-loop control a previously proposed multivariable robust control is considered. The robust control strategy analyzed consists of a multivariable Proportional-Integral controller found using an algorithm with a Linear Matrix Inequalities (LMI) formulation proposed by the autho...

Hernandez-torres, David; Riu, Delphine; Sename, Olivier; Druart, Florence

2011-01-01

374

Small-angle stability analysis of a linear control system for a high power communication satellite  

Science.gov (United States)

A small angle stability analysis is presented for one particular configuration of a high power communication satellite having a linear control system. Both the central body and the solar array are treated as rigid bodies. The control system studied consists of three-axis control of the central body and one-axis control of the solar array rotation relative to the central body. The results yield preliminary indications of the relation of stability to satellite inertias and control gains.

Omalley, T. A.

1972-01-01

375

Analysis of instantaneous feedback control system for SPWM inverter  

Science.gov (United States)

This paper deals with the closed-loop control method for an SPWM inverter used in a dc-link VSCF electrical power system. An instantaneous feedback control system is proposed, in which an ac current inner loop and an ac voltage outer loop are involved. For a 1 kVA single phase SPWM inverter, the closed-loop control system is designed and analyzed. The result of the experiments shows that the SPWM inverter with instantaneous feedback control has good static and dynamic electrical performance, with little distortion in the output waveform and the output voltage variation due to the variable dc voltage being effectively suppressed. It is suitable to use this closed-loop control method in a system equipped by a permanent magnet generator.

Zhou, Xing-Sheng; Yan, Yang-Guang

1993-02-01

376

Analysis of behavioral requirements for component-based machine controllers  

Science.gov (United States)

Machine controllers built from standardized software components have the greatest potential to reap open architecture benefits--including plug-and-play, reusability and extensibility. A challenge to component-based controllers relates to standardizing behavior in a non- restrictive manner to accommodate component packaging and component integration. Control component packaging requires behavior to be dependable, well-defined, and well-understood among a variety of users to help ensure the reusability of the component, the reliability of the component, and the correctness of the system built using the component. Integration of control components requires that the behavior model is consistent not just within a single component, but across all components in a system so that the components interoperate correctly. At the same time, the component behavioral model must be reasonably flexible to accommodate all behavioral situations and not be restrictive to a single programming methodology. Further, not all the behavior in the system may be pre-packaged as part of a component. Thus, another issue is the suitability of the standard behavior model for programming and integration of new control logic. Ideally, we need a vendor-neutral, tool-neutral, controller- neural behavior model to allow the export/import of any and all types of control logic programs. This paper will analyze the requirements of component-based, machine controller behavior, then offer a refinement of a Finite State Machine as the basis of a behavior model to satisfy these requirements. Examples will be presented based on the behavioral model the efforts of the Open, Modular, Architecture Controller User's Group Application Programming Interface for standardized, interchangeable machine controller components.

Proctor, Frederick M.; Michaloski, John L.; Birla, Sushil; Weinert, George F.

2001-02-01

377

Simulation Analysis of Computer-Controlled pressurization for Mixture Ratio Control  

Science.gov (United States)

A procedural code (C++) simulation was developed to investigate potentials for mixture ratio control of pressure-fed spacecraft rocket propulsion systems by measuring propellant flows, tank liquid quantities, or both, and using feedback from these measurements to adjust propellant tank pressures to set the correct operating mixture ratio for minimum propellant residuals. The pressurization system eliminated mechanical regulators in favor of a computer-controlled, servo- driven throttling valve. We found that a quasi-steady state simulation (pressure and flow transients in the pressurization systems resulting from changes in flow control valve position are ignored) is adequate for this purpose. Monte-Carlo methods are used to obtain simulated statistics on propellant depletion. Mixture ratio control algorithms based on proportional-integral-differential (PID) controller methods were developed. These algorithms actually set target tank pressures; the tank pressures are controlled by another PID controller. Simulation indicates this approach can provide reductions in residual propellants.

Alexander, Leslie A.; Bishop-Behel, Karen; Benfield, Michael P. J.; Kelley, Anthony; Woodcock, Gordon R.

2005-01-01

378

Control, stability analysis and grid integration of wind turbines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In Chapters 2 and 3 of the thesis we propose a self-scheduled control method for a doubly-fed induction generator driven by a wind turbine (DFIGWT), whose rotor is connected to the power grid via two back-to-back PWM power converters. We design a controller for this system using the linear matrix inequality based approach to linear parameter varying (LPV) systems, which takes into account the nonlinear dynamics of the system. We propose a two-loop hierarchical control structure. The inner-loo...

Wang, Chen

2011-01-01

379

Game Analysis of Internal Control and Risk Management  

Directory of Open Access Journals (Sweden)

Full Text Available Based on examining links and differences between internal control and risk management from their definition,this paper mainly analyzes their relation with game theory. A complete information static game model isestablished and payoff functions for managers and investors are designed. The result shows that the decrease ofbusiness risk cannot be realized by severe penalties, instead, the frequency of internal control in risk monitoringmust be taken into consideration, and otherwise it will stimulate enterprise risk monitoring paradox. It is aneffective way for enterprises to reduce risk by lowering the cost of internal control in risk monitoring andimproving the ability of risk prevention.

Yanhong Pang

2013-08-01

380

Numerical analysis and optimal control of induction heating hardening  

Science.gov (United States)

This work is presented a mathematical model of the electromagnetic and heating processes in cylindrical body placed in the inductor and is developed controller, which provide mode of metal hardening. Here, is a simplified version of the problem we shall try to prescribe a given isothermal line to be distinguished at a given final time. The mathematical model includes solving the electromagnetic and heating problems. With the finite elements method the mathematical model is lead to the linear system ODEs. This allows to be used the predictive control system theory and develop a controller which provides a mode of metal hardening.

Gilev, Bogdan; Yonchev, Andrey; Penev, Dimitar

2010-10-01

 
 
 
 
381

Automatic analysis of signals during Eddy currents controls  

International Nuclear Information System (INIS)

A method and the corresponding instrument have been developed for automatic analysis of Eddy currents testing signals. This apparatus enables at the same time the analysis, every 2 milliseconds, of two signals at two different frequencies. It can be used either on line with an Eddy Current testing instrument or with a magnetic tape recorder

382

Comparative analysis of some aspects of mitochondrial metabolism in differentiated and undifferentiated neuroblastoma cells.  

Science.gov (United States)

The aim of the present study is to clarify some aspects of the mechanisms of regulation of mitochondrial metabolism in neuroblastoma (NB) cells. Experiments were performed on murine Neuro-2a (N2a) cell line, and the same cells differentiated by all-trans-retinoic acid (dN2a) served as in vitro model of normal neurons. Oxygraphy and Metabolic Control Analysis (MCA) were applied to characterize the function of mitochondrial oxidative phosphorylation (OXPHOS) in NB cells. Flux control coefficients (FCCs) for components of the OXPHOS system were determined using titration studies with specific non-competitive inhibitors in the presence of exogenously added ADP. Respiration rates of undifferentiated Neuro-2a cells (uN2a) and the FCC of Complex-II in these cells were found to be considerably lower than those in dN2a cells. Our results show that NB is not an exclusively glycolytic tumor and could produce a considerable part of ATP via OXPHOS. Two important enzymes - hexokinase-2 and adenylate kinase-2 can play a role in the generation of ATP in NB cells. MCA has shown that in uN2a cells the key sites in the regulation of OXPHOS are complexes I, II and IV, whereas in dN2a cells complexes II and IV. Results obtained for the phosphate and adenine nucleotide carriers showed that in dN2a cells these carriers exerted lower control over the OXPHOS than in undifferentiated cells. The sum of FCCs for both types of NB cells was found to exceed significantly that for normal cells suggesting that in these cells the respiratory chain was somehow reorganized or assembled into large supercomplexes. PMID:24072403

Klepinin, Aleksandr; Chekulayev, Vladimir; Timohhina, Natalja; Shevchuk, Igor; Tepp, Kersti; Kaldma, Andrus; Koit, Andre; Saks, Valdur; Kaambre, Tuuli

2014-02-01