WorldWideScience
1

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

OpenAIRE

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, knowl...

Khadka C; Vacik H

2012-01-01

2

Stochastic Control Analysis for Biochemical Reaction Systems  

OpenAIRE

In this paper, we investigate how stochastic reaction processes are affected by external perturbations. We describe an extension of the deterministic metabolic control analysis (MCA) to the stochastic regime. We introduce stochastic sensitivities for mean and covariance values of reactant concentrations and reaction fluxes and show that there exist MCA-like summation theorems among these sensitivities. The summation theorems for flux variances are shown to depend on the size...

Kim, Kyung Hyuk; Sauro, Herbert M.

2009-01-01

3

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

4

A Study of MCA Learning Algorithm for Incident Signals Estimation  

Directory of Open Access Journals (Sweden)

Full Text Available Many signal subspace-based approaches have already been proposed for determining the fixed Direction of Arrival (DOA of plane waves impinging on an array of sensors. Two procedures for DOA estimation based neural network are presented. Firstly, Principal Component Analysis (PCA is employed to extract the maximum eigenvalue and eigenvector from signal subspace to estimate DOA. Secondly, Minor component analysis (MCA is a statistical method of extracting the eigenvector associated with the smallest eigenvalue of the covariance matrix. In this paper, we will modify a MCA learning algorithm to enhance the Convergence, where a Convergence is essential for MCA algorithm towards practical applications. The learning rate parameter is also presented, which ensures fast convergence of the algorithm, because it has direct effect on the convergence of the weight vector and the error level is affected by this value. MCA is performed to determine the estimated DOA. Simulation results will be furnished to illustrate the theoretical results achieved.

Rashid Ahmed

2014-12-01

5

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

6

Miniature-MCA technology developments  

Energy Technology Data Exchange (ETDEWEB)

We have recently reduced the size of multichannel analyzers (MCAs) and have implemented more features in hardware to relieve software requirements. We built and tested a spectroscopy grade, 4096-channel MCA. Exclusive of amplifier and power supply, it fits on two boards each approximately 7 by 15 cm. This paper discusses the features and performance of the analyzer and some reasonable applications of these technologies.

Halbig, J.K.; Klosterbuer, S.F.; Stephens, M.M.; Biddle, R.S.

1991-12-31

7

Miniature-MCA technology developments  

Energy Technology Data Exchange (ETDEWEB)

We have recently reduced the size of multichannel analyzers (MCAs) and have implemented more features in hardware to relieve software requirements. We built and tested a spectroscopy grade, 4096-channel MCA. Exclusive of amplifier and power supply, it fits on two boards each approximately 7 by 15 cm. This paper discusses the features and performance of the analyzer and some reasonable applications of these technologies.

Halbig, J.K.; Klosterbuer, S.F.; Stephens, M.M.; Biddle, R.S.

1991-01-01

8

A VAX and PC-based data acquisition system for MCA, scanning and list-mode analysis  

Science.gov (United States)

The design of the data acquisition system for the National Accelerator Centre's nuclear microprobe is described. The system consists of an intelligent PC scanner and imaging terminal, interfaced to a VAX-11/750 running a general purpose data acquisition package XSYS. In this way, the user friendliness of a dedicated, intelligent scanner has been combined with the flexibility of a general purpose data acquisition package. It is illustrated how simple tasks such as beam focussing, area of interest localization, and quantitative single spot PIXE or RBS analysis can be performed with minimal complexity, whereas requirements of a more complex nature can be implemented routinely using the general purpose acquisition package with standard command files. Even unique studies can be performed by means of minor software modifications.

Churms, C. L.; Pilcher, J. V.; Springhorn, K. A.; Tapper, U. A. S.

1993-05-01

9

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)

10

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

11

The Metacaspase (Mca1p) has a Dual Role in Farnesol-induced Apoptosis in Candida albicans.  

Science.gov (United States)

Manipulating the apoptotic response of Candida albicans may help in the control of this opportunistic pathogen. The metacaspase Mca1p has been described as a key protease for apoptosis in C. albicans but little is known about its cleavage specificity and substrates. We therefore initiated a series of studies to describe its function. We used a strain disrupted for the MCA1 gene (mca1?/?) and compared its proteome to that of a wild-type isogenic strain, in the presence and absence of a known inducer of apoptosis, the quorum-sensing molecule farnesol. Label-free and TMT labeling quantitative proteomic analyses showed that both mca1 disruption and farnesol treatment significantly affected the proteome of the cells. The combination of both conditions led to an unexpected biological response: the strong overexpression of proteins implicated in the general stress. We studied sites cleaved by Mca1p using native peptidomic techniques, and a bottom-up approach involving GluC endoprotease: there appeared to be a "K/R" substrate specificity in P1 and a "D/E" specificity in P2. We also found 77 potential substrates of Mca1p, 13 of which validated using the most stringent filters, implicated in protein folding, protein aggregate resolubilization, glycolysis, and a number of mitochondrial functions. An immunoblot assay confirmed the cleavage of Ssb1p, a member of the HSP70 family of heat-shock proteins, in conditions where the metacaspase is activated. These various results indicate that Mca1p is involved in a limited and specific proteolysis program triggered by apoptosis. One of the main functions of Mca1p appears to be the degradation of several major heat-shock proteins, thereby contributing to weakening cellular defenses and amplifying the cell death process. Finally, Mca1p appears to contribute significantly to the control of mitochondria biogenesis and degradation. Consequently, Mca1p may be a link between the extrinsic and the intrinsic programmed cell death pathways in C. albicans. PMID:25348831

Léger, Thibaut; Garcia, Camille; Ounissi, Marwa; Lelandais, Gaëlle; Camadro, Jean-Michel

2015-01-01

12

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

13

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

14

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

Directory of Open Access Journals (Sweden)

Full Text Available 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.

Ibrahiem Abdul Razak Al-Hadu, Lariyah Mohd Sidek, Mohamed Nor Mohamed Desa, Noor Ezlin Ahmad Basri

2011-09-01

15

Magnetic resonance angiographic evaluation of STA-MCA anastomoses in comparison with intraoperative hemodynamic studies  

Energy Technology Data Exchange (ETDEWEB)

Fifty superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses were performed on 46 patients (27 had ICA occlusion; 3, MCA occlusion, and 16, moyamoya disease) with the patency being demonstrated by conventional angiography. Magnetic resonance angiography (MRA) was applied to these cases for evaluating the MCA perfusion through STA-MCA anastomoses. In conjunction with three-dimensional gradient-echo acquisitions, selective presaturation was used to confirm the perfusion area via a given STA-MCA anastomosis. Cortical artery pressure and anastomotic blood flow were measured intraoperatively and compared with the MRA evaluations of the STA-MCA anastomoses. The results of the MRA evaluation were classified into one of the following four grades: Grade 1, poor visualization of the cortical branches of the MCA; Grade 2, only the cortical branches of the MCA were visualized; Grade 3, the MCA from the M{sub 2} to cortical branches was clearly visualized, and Grade 4, the MCA from the M{sub 1} to cortical branches was clearly visualized. The frequencies of Grades 1, 2, 3, and 4 were 30, 32, 22, and 16%, respectively. In ICA occlusion, Grades 3 and 4 were 69%, and in moyamoya disease, Grades 1 and 2 were 65%. While the MRA grades of STA-MCA anastomoses showed significant correlation with anastomotic blood flow, there was no correlation with respect to cortical arterial pressure. These results suggest that MRA could play an important role not only in demonstrating patency of STA-MCA anastomoses, but also in evaluating the perfusion area via STA-MCA anastomoses. Additionally, critical points of MRA visualization of STA-MCA anastomoses would include the size of the perfused vessels and anastomotic blood flow. (author)

Okada, Yoshikazu; Kagawa, Reiko [Shimane Medical Univ., Izumo (Japan); Shima, Takeshi; Nishida, Masahiro; Yamane, Kanji; Hatayama, Takashi; Yamanaka, Chie; Kajima, Toshio

1997-06-01

16

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

17

P-selectin antibody reduces hemorrhage and infarct volume resulting from MCA occlusion in the rat.  

Science.gov (United States)

We investigated the effect of an anti-P-selectin antibody (RMP-1) on ischemic cell damage and hemorrhage after transient middle cerebral artery occlusion (MCAo) in the rat. Animals were divided into four groups: (1) antibody (Ab) 1 group (n = 14) RMP-1 (2 mg/kg) was administered to rats 1 h prior to induction of 2 h of MCA occlusion; (2) control-vehicle group Ab2 (n = 12) rats were subjected to the same experimental protocol, except that an isotype-matched control antibody was administered; (3) Abl group (n = 10) rats were subjected to 2 h of MCA occlusion and RMP-1 (2 mg/kg) was administered upon reperfusion; (4) control-vehicle group Ab2 (n = 10) rats were subjected to the same experimental protocol, except that an isotype-matched control antibody was administered. Animals were sacrificed 48 h after onset of the MCAo for histological evaluation of infarction and hemorrhage, and to quantify number of neutrophils. The lesion volume was significantly smaller only in pretreated rats (RMP-1 group, 18.7+/-3.1%) compared to the vehicle-treated (31.6+/-2.6%) group (P<0.01). Total area of hemorrhage (5.94 x 10(3)+/-2.86 x 10(3) microm2) in the pre MCAo RMP-1 treated group animals was significantly reduced (P<0.02) compared to the vehicle group (6.1 x 10(4)+/-3.42 x 10(4) microm2), respectively. Our data demonstrate that administration of the anti-P-selectin antibody before transient focal cerebral ischemia in rat brain reduces ischemic cell damage and petechial hemorrhage. PMID:9879676

Goussev, A V; Zhang, Z; Anderson, D C; Chopp, M

1998-11-26

18

A SNP in OsMCA1 responding for a plant architecture defect by deactivation of bioactive GA in rice.  

Science.gov (United States)

Plant architecture directly affects biomass in higher plants, especially grain yields in agricultural crops. In this study, we characterized a recessive mutant, plant architecture determinant (pad), derived from the Oryza sativa ssp. indica cultivar MH86. The mutant exhibited severe dwarf phenotypes, including shorter and stunted leaves, fewer secondary branches during both the vegetative and reproductive growth stages. Cytological studies revealed that pad mutant growth defects are primarily due to the inhibition of cell expansion. The PAD gene was isolated using a map-based cloning strategy. It encodes a plasma membrane protein OsMCA1 and a SNP responsible for a single amino acid change was found in the mutant. PAD was universally expressed in rice tissues from the vegetative to reproductive growth stages, especially in seedlings, nodes and rachillae. Quantitative real-time PCR analysis revealed that the most of the genes responding to gibberellin (GA) metabolism were up-regulated in pad mutant internodes. The endogenous GA content measurement revealed that the levels of GA1 were significantly decreased in the third internode of pad mutants. Moreover, a GA response assay suggested that OsMCA1/PAD might be involved in the regulation of GA metabolism and signal transduction. Our results revealed the pad is a loss-of-function mutant of the OsMCA1/PAD, leading to upregulation of genes related to GA deactivation, which decreased bioactive GA levels. PMID:25307286

Liu, Zhenwei; Cheng, Qin; Sun, Yunfang; Dai, Huixia; Song, Gaoyuan; Guo, Zhibin; Qu, Xuefeng; Jiang, Daiming; Liu, Chuan; Wang, Wei; Yang, Daichang

2015-01-01

19

Phobos - Control network analysis  

Science.gov (United States)

Initial analysis of the Mariner 9 high resolution pictures of Phobos surface features has been completed. A control network of 38 landmarks has been established and used to determine the physical size, shape, orientation, libration, and topography properties of Phobos. The results verified the synchronous rotation of Phobos and revealed a libration of approximately 5 deg in the orbit plane of Phobos. A preliminary map of Phobos, based on the control network analysis, is given.

Duxbury, T. C.

1974-01-01

20

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

21

Clipping of bilateral MCA aneurysms and a coiled ACOM aneurysm through a modified lateral supraorbital craniotomy.  

Science.gov (United States)

We showcase the microsurgical clipping of a left middle cerebral artery (MCA) aneurysm-(B) done through a modified right lateral supraorbital craniotomy, as well as clipping of a previously coiled anterior communicating (ACOM) artery aneurysm-(C) and a bilobed right MCA aneurysm-(A). Splitting of the right sylvian fissure is initially performed following which a subfrontal approach is used to expose and dissect the contralateral sylvian fissure. The left MCA aneurysm is identified and clipped. The ACOM aneurysm is then clipped following multiple clip repositioning based on flow measurements. The right MCA aneurysm is then identified and each lobe is clipped separately. The first picture showcased in this video is a side to side right and left ICA injection in AP projection. In this picture, (A) points to the bilobed right MCA aneurysm, (B) to the left middle cerebral artery (MCA) aneurysm, and (C) to the previously coiled anterior communicating (ACOM) artery aneurysm. The red dotted line shows that both MCA aneurysms lie within the same plane which makes it easier to clip both of them, through one small craniotomy. The video can be found here: http://youtu.be/4cQC7nHsL5I . PMID:25554841

Hage, Ziad A; Charbel, Fady T

2015-01-01

22

Serum CA549 in primary breast cancer: comparison with CA15.3 and MCA.  

OpenAIRE

We carried out a comparison of three commonly used mucin markers, CA549, CA15.3 and MCA. Serum samples from 184 healthy women and 237 patients with primary breast cancer were evaluated. The markers were measured using commercially available immunometric assays. Like CA15.3 and MCA, CA549 was significantly associated with tumour size and lymph node status, being an effective indicator of tumour bulk. CA549 was significantly correlated with both CA15.3 and MCA. Positive/negative concordance rat...

Gion, M.; Plebani, M.; Mione, R.; Penzo, C.; Meo, S.; Burlina, A.

1994-01-01

23

(Im)Perfect robustness and adaptation of metabolic networks subject to metabolic and gene-expression regulation: marrying control engineering with metabolic control analysis  

Science.gov (United States)

Background Metabolic control analysis (MCA) and supply–demand theory have led to appreciable understanding of the systems properties of metabolic networks that are subject exclusively to metabolic regulation. Supply–demand theory has not yet considered gene-expression regulation explicitly whilst a variant of MCA, i.e. Hierarchical Control Analysis (HCA), has done so. Existing analyses based on control engineering approaches have not been very explicit about whether metabolic or gene-expression regulation would be involved, but designed different ways in which regulation could be organized, with the potential of causing adaptation to be perfect. Results This study integrates control engineering and classical MCA augmented with supply–demand theory and HCA. Because gene-expression regulation involves time integration, it is identified as a natural instantiation of the ‘integral control’ (or near integral control) known in control engineering. This study then focuses on robustness against and adaptation to perturbations of process activities in the network, which could result from environmental perturbations, mutations or slow noise. It is shown however that this type of ‘integral control’ should rarely be expected to lead to the ‘perfect adaptation’: although the gene-expression regulation increases the robustness of important metabolite concentrations, it rarely makes them infinitely robust. For perfect adaptation to occur, the protein degradation reactions should be zero order in the concentration of the protein, which may be rare biologically for cells growing steadily. Conclusions A proposed new framework integrating the methodologies of control engineering and metabolic and hierarchical control analysis, improves the understanding of biological systems that are regulated both metabolically and by gene expression. In particular, the new approach enables one to address the issue whether the intracellular biochemical networks that have been and are being identified by genomics and systems biology, correspond to the ‘perfect’ regulatory structures designed by control engineering vis-à-vis optimal functions such as robustness. To the extent that they are not, the analyses suggest how they may become so and this in turn should facilitate synthetic biology and metabolic engineering. PMID:24261908

2013-01-01

24

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

25

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

26

Unilateral Moyamoya Phenomenon Due to MCA Occlusion in a Child Presenting with Intracerebral Hemorrhage  

OpenAIRE

Spontaneous middle cerebral artery (MCA) occlusion leading to moyamoya phenomenon is different from classical moyamoya disease. Previous studies have reported such phenomena in adults with ischemic lesions, except for a solitary case in a child. We report a case of a ten-year old girl who presented with a deep intracerebral hematoma and a normal ipsilateral middle cerebral artery on initial evaluation by CT. Subsequently, on follow-up angiography, the ipsilateral MCA was occluded with evidenc...

Srikanth, S. G.; Nagarajan, K.; Chandrashekar, H. S.; Vasudev, M. K.; Pillai, Shibu V.

2006-01-01

27

In-house development of an FPGA-based MCA8K for gamma-ray spectrometer.  

Science.gov (United States)

The objective of this work is domestic development of electronics instruments. It used for measuring ionization radiation and practical training at Nuclear Research Institute (NRI), Dalat, Vietnam. The aim of this work is to study and develop a novel MCA8k for Gamma-ray spectrometer concerning experimental nuclear physics. An approach for design and construction of the aforementioned instrument is to apply logic integrating techniques via Field Programmable Gate Arrays (FPGA) under Max?+?PlusII, Altera. The instrument allows interfacing to PC with self-developed application software. Scientific significance of this work is partly to contribute to opening a research direction in the field of nuclear electronics science for design and construction of radiation measurement instruments with the advanced IC technology in Vietnam. Practical significance of this work is partly to contribute to enhancement of capabilities in developing radiation measurement instruments for experimental research as well as practical training in nuclear physics. The advantages of FPGA: overcoming ballistic deficit, decrement of serial and parallel noise, flexible in programming, control of the system by software without an interfere of hardware. The disadvantages of FPGA: requirement of good knowledge of VHDL and professional tools for development of a expected project. A new electronics module of MCA8k has been achieved. Some main results obtained from the experimental testing are as follows: differential nonlinearity (DNL) of FPGA-MCA8k approximately 1.27%, integral nonlinearity (INL) = 0.607%, time conversion???2.2 ?s, deadtime (DT) is 0.75%. Data Acquisition Program MCANRI written in VC (+ +)6.0, self-executed under Windows XP environment. PMID:25485201

Lanh, Dang; Son, Pham Ngoc; Son, Nguyen An

2014-01-01

28

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

29

Integrated modeling and control of flexible aircraft wings  

Science.gov (United States)

Structural control for vibration reduction has important applications in many research areas, including the effect of earthquakes on buildings and aerodynamic forces on aircraft stability and performance. Both passive and active control techniques have been implemented, with the best solution usually involving a passive approach followed by an active one. This thesis presents an integrated modeling and controller design approach. Modal Cost Analysis (MCA) and Output Covariance Constraint (OCC) control are used to reduce a high-order aeroelastic wing model to establish the best controller for the reduced-order model, with a constraint on the covariance of the vibration outputs. MCA seeks to keep the modes that have the highest contribution to a given cost function. Using iterations on the two processes will allow a lower-order controller to be designed and result in the same performance. The OCC and MCA methods and their respective algorithms are presented, and an approach to integrate the two procedures is given. NASA's model used in this thesis is applied to the MCA and OCC algorithms using MATLAB. A 40 th-order wing model is derived. The model reduction technique initially reduces the system to a 12th order one. A simulation of the OCC algorithm is performed on the reduced-order model and applied to the full-order model. The controller resulting in the best closed-loop performance is shown to significantly reduce the vibrations due to wind. A corresponding weighting matrix used in OCC is then used for a second round of MCA to further reduce the model to an 8th order model. A lower-order controller designed for this second model is shown to similarly reduce the output vibrations.

Wehr, Dagmara Anna

30

Functional disruption of yeast metacaspase, Mca1, leads to miltefosine resistance and inability to mediate miltefosine-induced apoptotic effects.  

Science.gov (United States)

Miltefosine (MI) is a novel, potential antifungal agent with activity against some yeast and filamentous fungal pathogens. We previously demonstrated in the model yeast, Saccharomyces cerevisiae, that MI causes disruption of mitochondrial membrane potential and apoptosis-like cell death via interaction with the Cox9p sub-unit of cytochrome c oxidase (COX). To identify additional mechanisms of antifungal action, MI resistance was induced in S. cerevisiae by exposure to the mutagen, ethyl methanesulfonate, and gene mutation(s) responsible for resistance were investigated. An MI-resistant haploid strain (H-C101) was created. Resistance was retained in the diploid strain (D-C101) following mating, confirming dominant inheritance. Phenotypic assessment of individual D-C101 tetrads revealed that only one mutant gene contributed to the MI-resistance phenotype. To identify this gene, the genome of H-C101 was sequenced and 17 mutated genes, including metacaspase-encoding MCA1, were identified. The MCA1 mutation resulted in substitution of asparagine (N) with aspartic acid (D) at position 164 (MCA1(N164D)). MI resistance was found to be primarily due to MCA1(N164D), as single-copy episomal expression of MCA1(N164D), but not two other mutated genes (FAS1(T1417I) and BCK2(T104A)), resulted in MI resistance in the wild-type strain. Furthermore, an MCA1 deletion mutant (mca1?) was MI-resistant. MI treatment led to accumulation of reactive oxygen species (ROS) in MI-resistant (MCA1(N164D)-expressing and mca1?) strains and MI-susceptible (MCA1-expressing) strains, but failed to activate Mca1 in the MI-resistant strains, demonstrating that ROS accumulation does not contribute to the fungicidal effect of MI. In conclusion, functional disruption of Mca1, leads to MI resistance and inability to mediate MI-induced apoptotic effects. Mca1-mediated apoptosis is therefore a major mechanism of MI-induced antifungal action. PMID:24731805

Biswas, Chayanika; Zuo, Xiaoming; Chen, Sharon C-A; Schibeci, Stephen D; Forwood, Jade K; Jolliffe, Katrina A; Sorrell, Tania C; Djordjevic, Julianne T

2014-06-01

31

Is local hypoperfusion the reason for transient neurological deficits after STA-MCA bypass for moyamoya disease?  

Science.gov (United States)

OBJECT Hyperperfusion is believed to be the cause of transient neurological events (TNEs) in patients with moyamoya disease (MMD) who have undergone an extracranial-to-intracranial (EC-IC) bypass between the superficial temporal artery (STA) and the middle cerebral artery (MCA). The objective of this study was to evaluate this possibility by analyzing cerebral blood flow (CBF) data obtained with thermal diffusion probes used at the authors' center. METHODS The authors examined postoperative cerebral perfusion in 31 patients with MMD who underwent a direct EC-IC STA-MCA bypass. A Hemedex Q500 flow probe was placed in the frontal lobe adjacent to the bypass and connected to a Bowman cerebral perfusion monitor, and CBF data were statistically analyzed using JMP 8.0.2 software. Seven patients experienced a TNE after surgery in the left hemisphere (that is, after left-sided surgery), manifesting as dysphasia approximately 24 hours postoperatively and which had improved by 48 hours. No TNEs were observed after right-sided surgeries. Operative and postoperative CBFs in the left side with the TNE were compared with those in the left side with no TNE and on the right side. RESULTS A detailed analysis of 64,980 minute-by-minute flow observations showed that the initial postbypass CBF was higher on the left side where the TNEs occurred. This CBF increase was followed by a widely fluctuating pattern and a statistically significant and sharp drop in perfusion (p < 0.001, mean difference of CBF between groups, paired t-test) associated with a TNE not observed in the other 2 groups. CONCLUSIONS On the basis of the authors' initial observations, an early-onset altered pattern of CBF was identified. These findings suggest local hypoperfusion as the cause of the TNEs. This hypoperfusion may originate from competing blood flows resulting from impaired cerebral autoregulation and a fluctuating flow in cerebral microcirculation. PMID:25343178

Mukerji, Nitin; Cook, Douglas J; Steinberg, Gary K

2015-01-01

32

Quality control in activation analysis  

International Nuclear Information System (INIS)

Analytical quality control is needed to ascertain the reliability of results from all types of analysis, including activation analysis. The a priory precision has to be combined with the statistics of counting in order to reach a state of statistical control. The Analysis of Precision is used to verify the absence of unknown sources of variability and to ascertain the absence of systematic biases or calibration errors by analyzing samples or reference materials with accurately known content or actual samples by an independent method. (author) 13 refs.; 6 tabs

33

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

34

Subcubic Control Flow Analysis Algorithms  

DEFF Research Database (Denmark)

We give the first direct subcubic algorithm for performing control flow analysis of higher-order functional programs. Despite the long held belief that inclusion-based flow analysis could not surpass the ``cubic bottleneck, '' we apply known set compression techniques to obtain an algorithm that runs in time O(n^3/log n) on a unit cost random-access memory model machine. Moreover, we refine the initial flow analysis into two more precise analyses incorporating notions of reachability. We give subcubic algorithms for these more precise analyses and relate them to an existing analysis from the literature.

Midtgaard, Jan; Van Horn, David

2009-01-01

35

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

36

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

Energy Technology Data Exchange (ETDEWEB)

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)

Li, M.; Carozza, C.; Guthrie, R.I.L. [McGill Metals Processing Center, Dept. of Mining and Metallurgical Engineering, McGill Univ., Montreal, Quebec (Canada)

2000-07-01

37

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

Energy Technology Data Exchange (ETDEWEB)

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)

Kume, Norihiko; Hayashida, Kohei; Cho, Ihn Ho; Iwama, Toru [National Cardiovascular Center, Suita, Osaka (Japan); Matsunaga, Naofumi

1997-10-01

38

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

Energy Technology Data Exchange (ETDEWEB)

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 {sup 99m}Tc-annexin V, animals underwent either single-photon emission computerized tomography (SPECT) or autoradiography followed by immunohistochemical analyses. There was abnormal, bilateral, multifocal uptake of {sup 99m}Tc-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.)

Mari, Carina; Goris, Michael L. [Division of Nuclear Medicine, Department of Radiology, Stanford University Hospital, CA 94305, Stanford (United States); Karabiyikoglu, Murat; Yenari, Midori Anne [Departments of Neurosurgery and Neurology, Stanford University Hospital, CA 94305, Stanford (United States); Tait, Jonathan F. [Department of Laboratory Medicine, University of Washington Medical Center, WA 98195-7110, Seattle (United States); Blankenberg, Francis G. [Division of Nuclear Medicine, Department of Radiology, Stanford University Hospital, CA 94305, Stanford (United States); Division of Pediatric Radiology, Department of Radiology, Stanford University, Lucile Salter Packard Children' s Hospital, 725 Welch Road, Room 1673, CA 94305, Palo Alto (United States)

2004-05-01

39

Controllability analysis for process and control system design  

OpenAIRE

Controllability is the ability of a process to achieve acceptable performance, and in this thesis we use controllability analysis in the design of buffer tanks, feedforward controllers, and multivariable controllers such as model predictive control (MPC).

There is still an increasing pressure on the process industry, both from competitors (prize and quality) and the society (safety and pollution), and one important contribution is a smooth and stable production. ...

Faanes, Audun

2003-01-01

40

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

41

Controllability analysis of decentralised linear controllers for polymeric fuel cells  

OpenAIRE

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 empl...

Serra Prat, Mari?a; Aguado, Joaqui?n; Ansede Pardo, Xavier; Riera Colomer, Jordi

2005-01-01

42

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.

43

RENT CONTROL: A COMPARATIVE ANALYSIS  

Directory of Open Access Journals (Sweden)

Full Text Available 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 socio-economic 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 should not be imposed in an absolutist fashion but rather place a

Sue-Mari Maass

2012-11-01

44

MCA4climate - a practical framework for pro-development climate policy  

DEFF Research Database (Denmark)

Climate is an inordinate challenge but also an inordinate opportunity to transform economies onto a low-carbon, resourcee !cient Green Economy path. Catalyzing clean energy will not only cut greenhouse-gas emissions as part of e”orts to limit a global temperature rise to under 2 degrees C or more, it also represents a way of curbing healthhazardous air pollution while o”ering a rapid path to address energy poverty, especially in rural areas of developing economies. Meanwhile enhancing ecosystems such as forests, mangroves and seagrasses in order to conserve their carbon stocks can also trigger multiple benefits from boosting water supplies and improving agriculture to maintaining natural sea defences and nurseries for fish. The 17th Conference of the Parties meeting in Durban, South Africa, later this year presents the world with another opportunity to advance the climate agenda and co-operative action under the UN Climate Convention. It is crucial that those actions are designed within a coherent and robust policy-planning framework to ensure that they are both cost-e”ective and compatible with broader social, economic and environmental goals. For developing countries, sound climatepolicy planning will also enhance access to climate finance from the developed ones. Climate-policy planning is a complex undertaking. Many developing countries are only just starting to consider how to go about it and some require improved access to the requisite knowledge, expertise and technical skills. Drawing upon best practices, tried and tested in other parts of the world, is clearly an advantage. The MCA4climate, a new UNEP initiative, is designed to assist policymakers, particularly in the developing world, in that endeavour. It o”ers concrete guidance and recommendations on a number of critical issues and proposes a formal framework for evaluating climate mitigation and adaptation policies, paving a practical way forward so that countries evolve sustainably and grow their economies in a way that keeps humanity’s footprint within planetary boundaries. It draws on the work of leading experts on climate policymaking from around the world and uses an innovative approach to assessing policies that ensures that climate policies and strategies take full account of developmental concerns and objectives. The MCA4climate initiative reflects UNEP’s mission to provide leadership and encourage partnership in caring for the environment by inspiring, informing and enabling nations and peoples to improve their quality of life without compromising that of future generations—issues at the centre of Rio+20 next year in Brazil as governments look to scale-up and accelerate the implementation of the agreements, including those relating to climate change, established in Rio in 1992.

Trevor, Morgan

2011-01-01

45

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.

46

Control Flow Analysis for BioAmbients  

DEFF Research Database (Denmark)

This paper presents a static analysis for investigating properties of biological systems specified in BioAmbients. We exploit the control flow analysis to decode the bindings of variables induced by communications and to build a relation of the ambients that can interact with each other. We eventually apply our analysis to an example of gene regulation by positive feedback taken from the literature.

Nielson, Flemming; Nielson, Hanne Riis

2007-01-01

47

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

48

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

49

The macroscopic analysis of radio – control problem  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. Contemporary stage technique’s development is to characterize of radio – control systems broad application. Analysis radio – control systems is based usually on microscopic principle. Actual task is macroscopic point of view in radio – control problem. Problem statement. For radio control problem decision it is necessary describe the dynamics of process in generalize form. It is possible in conditions when macroscopic analysis is principal method. In this method it is actual the discount of probability of task fulfillment and information quantity. It is necessary find out the dependence between information quantity, relative error and dynamic characters of systems. Theoretical results. The regularities of task probability fulfillment in radio – control problem were consideration in dependence from control information quantity, information ability and relative error of radio – control system. Time of task fulfillment was determined for radio – control. The influence of speed increase coefficient of task fulfillment was determined. Typical substitution models for radio- control systems and relative errors were considerate. The information abilities of substitution models with discount of time constants and belated time were determined. For task fulfillment probability of radio – control were determine the dependences from time constants, belated time and speed increase coefficient of task fulfillment probability. Conclusion. Achieve results permit transfer the analysis of radio – control process on new quality level. Information, probability and characters of radio – control systems were taken into consideration. The ability for determination of task fulfillment time was open.

V. O. Bychkovskyi

2013-12-01

50

Control rod drive mechanisms seismic analysis  

International Nuclear Information System (INIS)

In the Taishan joint-design, in order to finish Control Rod Drive Mechanism (CRDM) seismic analysis, a response spectrum analysis in combination with quasi-static analysis and a time history analysis are performed according to the different design stages and inputs. The simulated and simplified model of nonlinear structure is studied in the basic design stage; the translation of seismic input data and the use of nonlinear elements are studied in the detailed design stage. (authors)

51

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

52

Analysis Of Control Of Cooperating Robot Arms  

Science.gov (United States)

Paper presents theoretical analysis of general problem of how to control motions of, and forces exerted by, several multiple-rigid-link robot arms that cooperatively manipulate common rigid object. Emphasis mainly on construction, via full-dynamics approach, of control laws relatively independent of dynamical models.

Kreutz, Kenneth K.; Wen, John Ting-Yung

1991-01-01

53

76 FR 28193 - Amendments to Material Control and Accounting Regulations  

Science.gov (United States)

...Amendments to Material Control and Accounting Regulations AGENCY: Nuclear Regulatory...amendments to the material control and accounting (MC&A) regulations. These regulations...outdated term, as it does not include ``accounting,'' and thus does not fully...

2011-05-16

54

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

55

Open GENIE - Analysis and Control  

OpenAIRE

Open GENIE is the successor to the widely used and high successful GENIE program that is used as the principal front-end neutron data analysis tool at the ISIS spallation neutron source. In this paper, the background and motivation for the Open GENIE project are briefly reviewed, as is the progress to date. Some of the ideas and concepts making Open GENIE unique are demonstrated. Emphasis is given to how Open GENIE is being used as an integral component of the new ISIS contr...

Campbell, S. I.; Akeroyd, F. A.; Moreton-smith, C. M.

2002-01-01

56

77 FR 60482 - Regulatory Guide 5.67, Material Control and Accounting for Uranium Enrichment Facilities...  

Science.gov (United States)

...Guide 5.67, Material Control and Accounting for Uranium Enrichment Facilities Authorized...5.67, ``Material Control and Accounting for Uranium Enrichment Facilities Authorized...to develop their material control and accounting (MC&A) programs under Title...

2012-10-03

57

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

58

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

59

Control performance analysis of tandem EDG  

International Nuclear Information System (INIS)

Because tandem EDG(Emergency Diesel Generator) is composed of one generator in center and two engines in sides, the problem of load unbalance between two engine remains systematically. The tandem EDG is controlled by proportional integral differential controller, and control performance is closely related with load unbalance, hunting, starting time, and fast load change stability. When the problems about load unbalance, hunting, starting time, and fast load change stability occur in tandem EDG, these can be solved by the analysis of control performance

60

The design of database for analysis of data from multichannel analyzer  

International Nuclear Information System (INIS)

The use of database management system in analyzing data from multichannel analyzer (MCA) are studied and designed to bring up various types of data from MCA to microcomputer in neutron activation analysis work. RS-232 interface used in transmitting and receiving signals from MCA to microcomputer by asynchronous communication was studied. The software (PC-talk) used in receiving data from MCA and save data file on diskette in microcomputer was studied. Then the developing database program was used to analyze types of element, determine the content of elements and also report results

61

Integrated tools for control-system analysis  

Science.gov (United States)

The basic functions embedded within a user friendly software package (MATRIXx) are used to provide a high level systems approach to the analysis of linear control systems. Various control system analysis configurations are assembled automatically to minimize the amount of work by the user. Interactive decision making is incorporated via menu options and at selected points, such as in the plotting section, by inputting data. There are five evaluations such as the singular value robustness test, singular value loop transfer frequency response, Bode frequency response, steady-state covariance analysis, and closed-loop eigenvalues. Another section describes time response simulations. A time response for random white noise disturbance is available. The configurations and key equations used for each type of analysis, the restrictions that apply, the type of data required, and an example problem are described. One approach for integrating the design and analysis tools is also presented.

Ostroff, Aaron J.; Proffitt, Melissa S.; Clark, David R.

1989-01-01

62

The Mechanical Control Absorber reactivity dependence on the enrichment and burn-up in Candu-SEU super-cells  

International Nuclear Information System (INIS)

The objective of this work is to highlight some aspects of the local neutronic behaviour of the Candu SEU-43 fuel bundles (Slightly Enriched Uranium fuel bundles with 43 fuel elements). More exactly, the study refers to the dependence of some local neutronic parameters, mainly the reactivity, on the enrichment and the burn-up of the fuel. It was taken in consideration two types of super-cells: reference supercell (containing only fuel bundle and moderator) and perturbed supercell (containing fuel bundle, moderator and additionally a strong reactivity device). The considered reactivity device is the Mechanical Control Absorber (MCA). The performed parameters are: keff. values, MCA reactivities and flux distributions. For reaching this objective, it is used a local neutronic calculation methodology based on WIMS and PIJXYZ codes. The paper ends with an analysis of the obtained results. (authors)

63

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

64

A portable, photon analysis spectrometer for the assay of X- and gamma-ray emitting radionuclides  

International Nuclear Information System (INIS)

A portable, battery-po dered, multichannel analyzer (MCA) for use with Ge spectrometers has been developed for in-field use for the assay of x- and ?-ray emitting radionuclides. The spectrometer is capable of operating to rates greater than 150,000 counts per second. The analyzer is a Canberra InSpector MCA, that is equipped with the INEEL ultra-stable dual-energy pulser, and pulse injection with subsequent removal (PISR) circuitry. PCGAP, a set of MCA control and spectral analysis programs, was developed for use on a PC with a Windows NT Operating System. It includes an interactive peak analysis program as well as automatic spectral analysis programs for the X- and ?-ray regions, and a number of utility programs. The pulser peaks are calibrated with radioactive sources in terms of energy (i.e., their energy equivalents are measured) using the PCGAP spectral analysis package so that energy shifts, including those due to changes in temperature or count rate, do not cause a loss of energy calibration. The number of injected low- and high-energy-equivalent pulses is known so the stored pulser pulses can be used for a dead-time and random summing correction. The pulser peaks are also used to monitor any deterioration in spectral quality caused by noise, ground loops, etc. The results of performance tests to demonstrate the capabilities of this pulser-equipped InSpector are reported. (author)

65

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

66

Development of control material for hemoglobin analysis.  

Science.gov (United States)

Abstract Background: There is no certified control material for hemoglobin analysis which has the hemoglobin (Hb)A(2)/E level as high as found in ?-thalassemia trait, HbE trait, ?-thalassemia/HbE disease and homozygote of HbE, the thalassemia types found frequently in the Southeast Asian population. The aim of this study was to prepare the lyophilized hemoglobin control materials for hemoglobin analysis. Methods: Washed and dialysed erythrocytes of normal individuals and patients with ?-thalassemia trait, HbE trait, ?-thalassemia/HbE disease, homozygous HbE were lysed in 5% sucrose solution. The lyophilized hemoglobin control materials were prepared by using a freeze-drying (lyophilization) method. The high performance liquid chromatography (HPLC) analysis of lyophilized hemoglobin was performed after storing at ?20?C for 1, 15 and 30?days and for 3?months. Results: The chromatograms of lyophilized hemoglobin control materials showed similar patterns and similar levels of HbA, HbA(2)/E and HbF when compared with equivalent fresh whole blood. Moreover, the lyophilized hemoglobin presented a good correlation coefficient (r>0.990) of relationships between HPLC, low pressure liquid chromatography (LPLC) and capillary electrophoresis (CE) methods. Conclusions: The lyophilized hemoglobin could be developed and used as control materials for hemoglobin analysis. PMID:22070221

Pornprasert, Sakorn; Kongthai, Kunyakan; Waneesorn, Jarurin; Jaiping, Kanokwan; Treesuwan, Kallayanee

2011-11-10

67

Metabolic Control Analysis: Separable Matrices and Interdependence of Control Coefficients.  

Science.gov (United States)

A central quantity for the analysis of the interdependence of control coefficients is the Jacobian H of the pathway. For a simple metabolic chain, H is known to be tridiagonal. Its inverse H-1, which is required to calculate control coefficients, is semi-separable. A semi-separable nxn matrix (aij) has the characteristic property that it is decomposable into two triangles for each of which there are vectors r=(r1, . . . ,rn) and t=(t1, . . . ,tn) with aij=ritj. The exact definitions of semi-separability and the related separability of matrices are given in Appendix B. Owing to the semi-separability of H-1, the determinants of all 2x2 sub-matrices of elements located within one of the triangles are zero. Therefore, these triangles are regions of vanishing two-minors. The flux control coefficient matrix CJ is hown to be separable and the concentration control coefficient matrix Cs to be semi separable. Cs has, in addition, the peculiarity that the row vector is the same for both its upper and lower triangle. A feedback loop gives rise to a new sub-region of vanishing two-minors, thereby disturbing the semi-separability of the upper triangle of Cs. A recipe is given to graphically construct the regions of vanishing two-minors of concentration control coefficients. The notion of (semi-)separability allows assessment of all dependences of control coefficients for metabolic pathways.Copyright 1998 Academic Press PMID:9750182

Elsner; Giersch

1998-08-21

68

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

Energy Technology Data Exchange (ETDEWEB)

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 cerebral hemodynamic status before and after surgery

Ideguchi, Reiko; Enokizono, Mikako; Uetani, Masataka (Dept. of Radiological Sciences, Nagasaki Univ. Graduate School of Biomedical Sciences, Nagasaki (Japan)), e-mail: qqtt37gd9@forest.ocn.ne.jp; Morikawa, Minoru (Dept. of Radiology, Nagasaki Univ. School of Medicine, Nagasaki (Japan)); Ogawa, Yoji (Dept. of Radiology, Hanwa Daini Senboku Hospital, Osaka (Japan)); Nagata, Izumi (Dept. of Neurosurgery, Nagasaki Univ. School of Medicine, Nagasaki (Japan))

2011-04-15

69

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)

70

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

71

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

72

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 dispsition, 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

73

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.

Leopold Paszek

2008-01-01

74

Modeling Controller Tasks for Safety Analysis  

Science.gov (United States)

As control systems become more complex, the use of automated control has increased. At the same time, the role of the human operator has changed from primary system controller to supervisor or monitor. Safe design of the human computer interaction becomes more difficult. In this paper, we present a visual task modeling language that can be used by system designers to model human-computer interactions. The visual models can be translated into SpecTRM-RL, a blackbox specification language for modeling the automated portion of the control system. The SpecTRM-RL suite of analysis tools allow the designer to perform formal and informal safety analyses on the task model in isolation or integrated with the rest of the modeled system.

Brown, Molly; Leveson, Nancy G.

1998-01-01

75

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)

76

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

77

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

78

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

79

ABHD5/CGI-58 facilitates the assembly and secretion of apolipoprotein B lipoproteins by McA RH7777 rat hepatoma cells  

OpenAIRE

Lipolysis of stored triacylglycerols provides lipid precursors for the assembly of apolipoprotein B (apoB) lipoproteins in hepatocytes. Abhydrolase domain containing 5 (ABHD5) is expressed in liver and facilitates the lipolysis of triacylglycerols. To study the function of ABHD5 in lipoprotein secretion, we silenced the expression of ABHD5 in McA RH7777 cells using RNA interference and studied the metabolism of lipids and secretion of apoB lipoproteins. McA RH7777 cells deficient in ABHD5 sec...

Caviglia, Jorge M.; Sparks, Janet D.; Toraskar, Nikhil; Brinker, Anita M.; Yin, Terry C.; Dixon, Joseph L.; Brasaemle, Dawn L.

2009-01-01

80

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

81

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

82

Human reliability analysis of control room operators  

Energy Technology Data Exchange (ETDEWEB)

Human reliability is the probability that a person correctly performs some system required action in a required time period and performs no extraneous action that can degrade the system Human reliability analysis (HRA) is the analysis, prediction and evaluation of work-oriented human performance using some indices as human error likelihood and probability of task accomplishment. Significant progress has been made in the HRA field during the last years, mainly in nuclear area. Some first-generation HRA methods were developed, as THERP (Technique for human error rate prediction). Now, an array of called second-generation methods are emerging as alternatives, for instance ATHEANA (A Technique for human event analysis). The ergonomics approach has as tool the ergonomic work analysis. It focus on the study of operator's activities in physical and mental form, considering at the same time the observed characteristics of operator and the elements of the work environment as they are presented to and perceived by the operators. The aim of this paper is to propose a methodology to analyze the human reliability of the operators of industrial plant control room, using a framework that includes the approach used by ATHEANA, THERP and the work ergonomics analysis. (author)

Santos, Isaac J.A.L.; Carvalho, Paulo Victor R.; Grecco, Claudio H.S. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

2005-07-01

83

Large scale systems approximation: Analysis and control  

International Nuclear Information System (INIS)

This work concerns the study of the approximation of high dimensional systems by low order models. This approximation is defined by aggregation methods, the method based on singular perturbations and a relatively recent method. This later one is formulated in a particular representation of the system and is called balanced realisation method. The application of the approximation is then studied in the case of suboptimal control theory for the several defined models. The results of numerical simulation for the analysis and control are carried on two examples defined by a model of a nuclear reactor core of order nine and a steam generator of a fuel station of order twenty and permitted to develop a comparative study of the performances of the different methods analysed in the case of open loop and closed loop models

84

Applications toolkit for accelerator control and analysis  

International Nuclear Information System (INIS)

The Advanced Photon Source (APS) has taken a unique approach to creating high-level software applications for accelerator operation and analysis. The approach is based on self-describing data, modular program toolkits, and scripts. Self-describing data provide a communication standard that aids the creation of modular program toolkits by allowing compliant programs to be used in essentially arbitrary combinations. These modular programs can be used as part of an arbitrary number of high-level applications. At APS, a group of about 70 data analysis, manipulation, and display tools is used in concert with about 20 control-system-specific tools to implement applications for commissioning and operations. High-level applications are created using scripts, which are relatively simple interpreted programs. The Tcl/Tk script language is used, allowing creating of graphical user interfaces (GUIs) and a library of algorithms that are separate from the interface. This last factor allows greater automation of control by making it easy to take the human out of the loop. Applications of this methodology to operational tasks such as orbit correction, configuration management, and data review will be discussed

85

Radioactivity analysis of food and accuracy control  

International Nuclear Information System (INIS)

From the fact that radioactive substances have been detected from the foods such as agricultural and livestock products and marine products due to the accident of the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company, the Ministry of Health, Labour and Welfare stipulated new standards geared to general foods on radioactive cesium by replacing the interim standards up to now. Various institutions began to measure radioactivity on the basis of this instruction, but as a new challenge, a problem of the reliability of the data occurred. Therefore, accuracy control to indicate the proof that the quality of the data can be retained at an appropriate level judging from an objective manner is important. In order to consecutively implement quality management activities, it is necessary for each inspection agency to build an accuracy control system. This paper introduces support service, as a new attempt, for establishing the accuracy control system. This service is offered jointly by three organizations, such as TUV Rheinland Japan Ltd., Japan Frozen Foods Inspection Corporation, and Japan Chemical Analysis Center. This service consists of the training of radioactivity measurement practitioners, proficiency test for radioactive substance measurement, and personal authentication. (O.A.)

86

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

87

IMPROVING SOFTWARE SYSTEMS BY FLOW CONTROL ANALYSIS  

Directory of Open Access Journals (Sweden)

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

88

Decision-tree analysis of control strategies.  

Science.gov (United States)

A major focus of research on visually guided action is the identification of control strategies that map optical information to actions. The traditional approach has been to test the behavioral predictions of a few hypothesized strategies against subject behavior in environments in which various manipulations of available information have been made. While important and compelling results have been achieved with these methods, they are potentially limited by small sets of hypotheses and the methods used to test them. In this study, we introduce a novel application of data-mining techniques in an analysis of experimental data that is able to both describe and model human behavior. This method permits the rapid testing of a wide range of possible control strategies using arbitrarily complex combinations of optical variables. Through the use of decision-tree techniques, subject data can be transformed into an easily interpretable, algorithmic form. This output can then be immediately incorporated into a working model of subject behavior. We tested the effectiveness of this method in identifying the optical information used by human subjects in a collision-avoidance task. Our results comport with published research on collision-avoidance control strategies while also providing additional insight not possible with traditional methods. Further, the modeling component of our method produces behavior that closely resembles that of the subjects upon whose data the models were based. Taken together, the findings demonstrate that data-mining techniques provide powerful new tools for analyzing human data and building models that can be applied to a wide range of perception-action tasks, even outside the visual-control setting we describe. PMID:25316047

Weber, Romann M; Fajen, Brett R

2014-10-15

89

Design of Multivariable Controllers Using the Integrated Analysis Capability (IAC)  

Science.gov (United States)

Dynamic analysis and controls design for flexible spacecraft involves high-order dynamic systems with multiple inputs and outputs. Computer tools are essential for such analysis. The controls/structures interaction analysis capability of an inter-disciplinary computer software system, called the Integrated Analysis Capability (IAC), is described. An overview of IAC components and procedures is presented, and an example of a preliminary space station controls design is shown.

Bossi, J. A.; Price, G. A.; Wainkleblack, S. A.

1985-01-01

90

An informal analysis of flight control tasks  

Science.gov (United States)

Issues important in rotorcraft flight control are discussed. A perceptual description is suggested of what is believed to be the major issues in flight control. When the task is considered of a pilot controlling a helicopter in flight, the task is decomposed in several subtasks. These subtasks include: (1) the control of altitude, (2) the control of speed, (3) the control of heading, (4) the control of orientation, (5) the control of flight over obstacles, and (6) the control of flight to specified positions in the world. The first four subtasks can be considered to be primary control tasks as they are not dependent on any other subtasks. However, the latter two subtasks can be considered hierarchical tasks as they are dependent on other subtasks. For example, the task of flight control over obstacles can be decomposed as a task requiring the control of speed, altitude, and heading. Thus, incorrect control of altitude should result in poor control of flight over an obstacle.

Andersen, George J.

1991-01-01

91

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

92

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

Science.gov (United States)

...analysis and Hazard Analysis Critical Control...Section 123.6 Food and Drugs FOOD...for it, a hazard analysis to determine whether there are food safety hazards...whenever a hazard analysis reveals one or more food safety...

2010-04-01

93

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

94

Synthesis and luminescence properties of glass ceramics containing MSiO3:Eu2+ (M=Ca, Sr, Ba) phosphors for white LED  

International Nuclear Information System (INIS)

Eu2+ doped silicate glasses were prepared of the system 52SiO2-48MO: xEu2+(in molar ratio, M=Ca, Sr, Ba; x=1, 3, 5, 7, 9) by a high temperature melt-quenching method in a reducing atmosphere. Glass ceramics containing MSiO3:Eu2+(M=Ca, Sr, Ba) nano-phosphors were obtained after the heat treatment of the glass samples. The excitation, emission spectra and lifetime decay curves of 4f65d1?4f7 of Eu2+ were measured and interpreted with respect to their crystal structures and multi-site occupations of divalent europium in the hosts. Their excitation bands mainly extend from 450 to 250 nm, which is adaptable to the main emission region of the UV LED chip. With UV light excitation, the Eu2+ emission in CaSiO3, SrSiO3 and BaSiO3 shows blue, green and yellow colors centered at 440, 505 and 555 nm, respectively. The critical Eu2+concentration was studied and determined to be x=5 for both CaSiO3 and SrSiO3 and x=7 for BaSiO3 phosphors. The results show that the Eu2+ doped glass ceramic phosphors containing MSiO3 (M=Ca, Sr, Ba) nano-crystals can be used as potential matrix materials for a high power white LED pumped by the UV LED chip. - Highlights: ? Glass ceramic containing MSiO3:Eu2+ (M=Ca, Sr, Ba) phosphors prepared. ? Derived phosphors emit inrepared. ? Derived phosphors emit intensively blue, green and yellow colors. ? Their luminescence properties and crystal structures have been investigated. ? Concentration quenching effects observed and analyzed. ? Potential application for UV chip exciting white LED evaluated.

95

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)

96

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

97

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

98

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

99

Analysis and control of nonlinear systems  

CERN Document Server

A work on a hot topic in the field of control of nonlinear systems that ranges from mathematical system theory to practical industrial control applications. It addresses two fundamental questions in Systems and Control: how to plan the motion of a system and track the corresponding trajectory in presence of perturbations.

Levine, Jean

2009-01-01

100

Plasma membrane protein OsMCA1 is involved in regulation of hypo-osmotic shock-induced Ca2+ influx and modulates generation of reactive oxygen species in cultured rice cells  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mechanosensing and its downstream responses are speculated to involve sensory complexes containing Ca2+-permeable mechanosensitive channels. On recognizing osmotic signals, plant cells initiate activation of a widespread signal transduction network that induces second messengers and triggers inducible defense responses. Characteristic early signaling events include Ca2+ influx, protein phosphorylation and generation of reactive oxygen species (ROS. Pharmacological analyses show Ca2+ influx mediated by mechanosensitive Ca2+ channels to influence induction of osmotic signals, including ROS generation. However, molecular bases and regulatory mechanisms for early osmotic signaling events remain poorly elucidated. Results We here identified and investigated OsMCA1, the sole rice homolog of putative Ca2+-permeable mechanosensitive channels in Arabidopsis (MCAs. OsMCA1 was specifically localized at the plasma membrane. A promoter-reporter assay suggested that OsMCA1 mRNA is widely expressed in seed embryos, proximal and apical regions of shoots, and mesophyll cells of leaves and roots in rice. Ca2+ uptake was enhanced in OsMCA1-overexpressing suspension-cultured cells, suggesting that OsMCA1 is involved in Ca2+ influx across the plasma membrane. Hypo-osmotic shock-induced ROS generation mediated by NADPH oxidases was also enhanced in OsMCA1-overexpressing cells. We also generated and characterized OsMCA1-RNAi transgenic plants and cultured cells; OsMCA1-suppressed plants showed retarded growth and shortened rachises, while OsMCA1-suppressed cells carrying Ca2+-sensitive photoprotein aequorin showed partially impaired changes in cytosolic free Ca2+ concentration ([Ca2+]cyt induced by hypo-osmotic shock and trinitrophenol, an activator of mechanosensitive channels. Conclusions We have identified a sole MCA ortholog in the rice genome and developed both overexpression and suppression lines. Analyses of cultured cells with altered levels of this putative Ca2+-permeable mechanosensitive channel indicate that OsMCA1 is involved in regulation of plasma membrane Ca2+ influx and ROS generation induced by hypo-osmotic stress in cultured rice cells. These findings shed light on our understanding of mechanical sensing pathways.

Kurusu Takamitsu

2012-01-01

101

Tests for the MCA  

International Nuclear Information System (INIS)

Steam isolating valves are designed to shut off outside the containment the steam pipe penetrating the containment of the reactor building in case of a pipe break of the primary circuit. There are described experimental facilities at the hot steam reactor HDR, given examples for experiments as well as type and design of the SULZER steam isolating valves applied. (GL) 891 GL/GL 892 MKO

102

Multicyclic Controllable Twist Rotor Data Analysis  

Science.gov (United States)

Rsults provide functional relationship between rotor performance, blade vibratory loads and dual control settings and indicate that multicyclic control produced significant reductions in blade flatwise bending moments and blade root actuator control loads. Higher harmonic terms of servo flap deflection were found to be most pronounced in flatwise bending moment, transmission vertical vibration and pitch link vibratory load equations. The existing test hardware represents a satisfactory configuration for demonstrating MCTR technology and defining a data base for additional wind tunnel testing.

Wei, F. S.; Weisbrich, A. L.

1979-01-01

103

Solar Dynamic Power System Stability Analysis and Control  

Science.gov (United States)

The objective of this research is to conduct dynamic analysis, control design, and control performance test of solar power system. Solar power system consists of generation system and distribution network system. A bench mark system is used in this research, which includes a generator with excitation system and governor, an ac/dc converter, six DDCU's and forty-eight loads. A detailed model is used for modeling generator. Excitation system is represented by a third order model. DDCU is represented by a seventh order system. The load is modeled by the combination of constant power and constant impedance. Eigen-analysis and eigen-sensitivity analysis are used for system dynamic analysis. The effects of excitation system, governor, ac/dc converter control, and the type of load on system stability are discussed. In order to improve system transient stability, nonlinear ac/dc converter control is introduced. The direct linearization method is used for control design. The dynamic analysis results show that these controls affect system stability in different ways. The parameter coordination of controllers are recommended based on the dynamic analysis. It is concluded from the present studies that system stability is improved by the coordination of control parameters and the nonlinear ac/dc converter control stabilize system oscillation caused by the load change and system fault efficiently.

Momoh, James A.; Wang, Yanchun

1996-01-01

104

Analysis and Control of the Pan System via Sliding Mode Control  

OpenAIRE

In this paper, we obtain new results for the analysis and control of the Pan system (2010) using sliding mode control (SMC). The stability results derived in this paper for the control of the Pan system to stabilize about its unstable equilibrium at the origin have been derived using sliding mode control and Lyapunovstability theory. Numerical simulations are depicted to demonstrate the control results derived in this paper.

Sundarapandian Vaidyanathan

2012-01-01

105

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

106

Analysis of inventory difference using fuzzy controllers  

Energy Technology Data Exchange (ETDEWEB)

The principal objectives of an accounting system for safeguarding nuclear materials are as follows: (a) to provide assurance that all material quantities are present in the correct amount; (b) to provide timely detection of material loss; and (c) to estimate the amount of any loss and its location. In fuzzy control, expert knowledge is encoded in the form of fuzzy rules, which describe recommended actions for different classes of situations represented by fuzzy sets. The concept of a fuzzy controller is applied to the forecasting problem in a time series, specifically, to forecasting and detecting anomalies in inventory differences. This paper reviews the basic notion underlying the fuzzy control systems and provides examples of application. The well-known material-unaccounted-for diffusion plant data of Jaech are analyzed using both feedforward neural networks and fuzzy controllers. By forming a deference between the forecasted and observed signals, an efficient method to detect small signals in background noise is implemented.

Zardecki, A.

1994-08-01

107

Analysis of inventory difference using fuzzy controllers  

International Nuclear Information System (INIS)

The principal objectives of an accounting system for safeguarding nuclear materials are as follows: (a) to provide assurance that all material quantities are present in the correct amount; (b) to provide timely detection of material loss; and (c) to estimate the amount of any loss and its location. In fuzzy control, expert knowledge is encoded in the form of fuzzy rules, which describe recommended actions for different classes of situations represented by fuzzy sets. The concept of a fuzzy controller is applied to the forecasting problem in a time series, specifically, to forecasting and detecting anomalies in inventory differences. This paper reviews the basic notion underlying the fuzzy control systems and provides examples of application. The well-known material-unaccounted-for diffusion plant data of Jaech are analyzed using both feedforward neural networks and fuzzy controllers. By forming a deference between the forecasted and observed signals, an efficient method to detect small signals in background noise is implemented

108

Multi-Chromatic Analysis of SAR Images for Coherent Target Detection  

OpenAIRE

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by processing portions of the range spectrum of a synthetic aperture radar (SAR) image. According to the behavior of the SAR signal at the different sub-bands, MCA allows target classification. Two strategies have been experimented by processing TerraSAR-X images acquired over the Venice Lagoon...

Fabio Bovenga; Dominique Derauw; Fabio Michele Rana; Christian Barbier; Alberto Refice; Nicola Veneziani; Raffaele Vitulli

2014-01-01

109

INTERNAL AUDIT COMPARATIVE ANALYSIS - MANAGEMENT CONTROL CONCEPTS  

OpenAIRE

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 ...

MIHAI-DOREL JURCHESCU; N?T?LI?A-MIHAELA LESCONI-FRUMU?ANU

2010-01-01

110

Pushdown Control-Flow Analysis of Higher-Order Programs  

CERN Document Server

Context-free approaches to static analysis gain precision over classical approaches by perfectly matching returns to call sites---a property that eliminates spurious interprocedural paths. Vardoulakis and Shivers's recent formulation of CFA2 showed that it is possible (if expensive) to apply context-free methods to higher-order languages and gain the same boost in precision achieved over first-order programs. To this young body of work on context-free analysis of higher-order programs, we contribute a pushdown control-flow analysis framework, which we derive as an abstract interpretation of a CESK machine with an unbounded stack. One instantiation of this framework marks the first polyvariant pushdown analysis of higher-order programs; another marks the first polynomial-time analysis. In the end, we arrive at a framework for control-flow analysis that can efficiently compute pushdown generalizations of classical control-flow analyses.

Earl, Christopher; Van Horn, David

2010-01-01

111

Team One (GA/MCA) effort of the DOE 12 Tesla Coil Development Program. Progress report for the two quarters ending March 31, 1981  

International Nuclear Information System (INIS)

This report covers progress by Team One of the DOE/OFE/D and T 12 Tesla Coil Development Program during the first and second quarters of fiscal 1981. General Atomic Company is the Team One leader, with Magnetic Corporation of America (MCA) as industrial subcontractor. The basic mission of this effort is to demonstrate the feasibility of, and establish an engineering data base for utilizing bath cooled NbTi alloy to generate a peak toroidal field of 12 tesla in a tokamak reactor

112

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

113

Complexity, Analysis and Control of Singular Biological Systems  

CERN Document Server

Complexity, Analysis and Control of Singular Biological Systems follows the control of real-world biological systems at both ecological and phyisological levels concentrating on the application of now-extensively-investigated singular system theory. Much effort has recently been dedicated to the modelling and analysis of developing bioeconomic systems and the text establishes singular examples of these, showing how proper control can help to maintain sustainable economic development of biological resources. The book begins from the essentials of singular systems theory and bifurcations before tackling  the use of various forms of control in singular biological systems using examples including predator-prey relationships and viral vaccination and quarantine control. Researchers and graduate students studying the control of complex biological systems are shown how a variety of methods can be brought to bear and practitioners working with the economics of biological systems and their control will also find the ...

Zhang, Qingling; Zhang, Xue

2012-01-01

114

Pollution Analysis and Control in Petroleum Refineries  

OpenAIRE

Air, liquid and noise emissions from different equipment in petroleum refineries have been analyzed. Most data have been correlated or tabulated in order to make possible using them in estimating the impact of the different pollutants of refineries on the environment. Control measures for reducing these emissions have been also included.

Salem, A. B.

1990-01-01

115

Neutronics analysis of Browns Ferry 3 partial control rod insertion  

International Nuclear Information System (INIS)

This article summarizes results of a reactor neutronic analysis of the incomplete control rod insertion at the Browns Ferry Nuclear Power Station, Unit 3. The analysis focuses primarily on the power distribution in the core and on reactor criticality following failure of some control rods to insert fully after the first scram actuation. The analysis of the incident is based on the established sequence of events, the plant data, and the interpretation of instrumentation responses. The analysis also addresses the effects of initial core-power level on this transient

116

An averaging analysis of discrete-time indirect adaptive control  

Science.gov (United States)

An averaging analysis of indirect, discrete-time, adaptive control systems is presented. The analysis results in a signal-dependent stability condition and accounts for unmodeled plant dynamics as well as exogenous disturbances. This analysis is applied to two discrete-time adaptive algorithms: an unnormalized gradient algorithm and a recursive least-squares (RLS) algorithm with resetting. Since linearization and averaging are used for the gradient analysis, a local stability result valid for small adaptation gains is found. For RLS with resetting, the assumption is that there is a long time between resets. The results for the two algorithms are virtually identical, emphasizing their similarities in adaptive control.

Phillips, Stephen M.; Kosut, Robert L.; Franklin, Gene F.

1988-01-01

117

Analogy of the Coordination Chemistry of Alkaline Earth Metal and Lanthanide Ln²? Ions: The Isostructural Zoo of Mixed Metal Cages [IM(OtBu)?{Li(thf)}?(OH)] (M=Ca, Sr, Ba, Eu), [MM??(OPh)?(thf)?] (M=Ca, Sr, Ba, Sm, Eu, M?=Li, Na), and their Derivatives with 1,2-Dimethoxyethane  

OpenAIRE

As previously shown, alkali and alkaline earth metal iodides in nonaqueous, aprotic solvents behave like transition metal halides, forming cis- and trans-dihalides with various neutral O-donor ligands. These compounds can be used as precursors for the synthesis of new mixed alkali/alkaline earth metal aggregates. We show here that Ln²? ions form isostructural cluster compounds. Thus, with LiOtBu, 50 % of the initial iodide can be replaced in MI?, M=Ca, Sr, Ba, Eu, to...

Maudez, William; Meuwly, Markus; Fromm, Katharina M.

2008-01-01

118

Time Series Analysis Forecasting and Control  

CERN Document Server

A modernized new edition of one of the most trusted books on time series analysis. Since publication of the first edition in 1970, Time Series Analysis has served as one of the most influential and prominent works on the subject. This new edition maintains its balanced presentation of the tools for modeling and analyzing time series and also introduces the latest developments that have occurred n the field over the past decade through applications from areas such as business, finance, and engineering. The Fourth Edition provides a clearly written exploration of the key methods for building, cl

Box, George E P; Reinsel, Gregory C

2011-01-01

119

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

120

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

121

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

OpenAIRE

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

122

National Ignition Facility (NIF) Control Network Design and Analysis  

OpenAIRE

This paper describes the requirements, design, and analysis of the control network for the National Ignition Facility (NIF). The network uses Ethernet technology throughout and ATM is used for efficient digital video transport.

Bryant, R. M.; Carey, R. W.; Claybourn, R. V.; Pavel, G.; Schaefer, W. J.

2001-01-01

123

Analysis and design of networked control systems  

CERN Document Server

This monograph focuses on characterizing the stability and performance consequences of inserting limited-capacity communication networks within a control loop. The text shows how integration of the ideas of control and estimation with those of communication and information theory can be used to provide important insights concerning several fundamental problems such as: ·         minimum data rate for stabilization of linear systems over noisy channels; ·         minimum network requirement for stabilization of linear systems over fading channels; and ·         stability of Kalman filtering with intermittent observations. A fundamental link is revealed between the topological entropy of linear dynamical systems and the capacities of communication channels. The design of a logarithmic quantizer for the stabilization of linear systems under various network environments is also extensively discussed and solutions to many problems of Kalman filtering with intermittent observations are de...

You, Keyou; Xie, Lihua

2015-01-01

124

Magnetic field regulation control system analysis  

Energy Technology Data Exchange (ETDEWEB)

This study comprises (1) an analytical characterization of the Cameca ion microscope`s magnetic field regulation circuitry and (2) comparisons between the analytical predictions and the measured performance of the control system. It is the first step in a project to achieve routine field regulation better than 10ppm. The control loop was decomposed into functional subcircuits and simulated in SPICE to determine DC, AC, and transient response. Transfer functions were extracted from SPICE, simplified, and analyzed in MATLAB. Both SPICE and MATLAB simulations were calculated for step inputs, and these results were compared to actual measurements. Magnetic field fluctuations were measured at high mass resolving power. The frequency spectrum of the fluctuations was analyzed by FFT. Difficulties encountered and implications for future work are discussed.

Badelt, S.W. [Lawrence Livremore National Lab., CA (United States)

1996-05-01

125

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

126

Error control variability in pathway-based microarray analysis  

OpenAIRE

Motivation: The decision to commit some or many false positives in practice rests with the investigator. Unfortunately, not all error control procedures perform the same. Our problem is to choose an error control procedure to determine a P-value threshold for identifying differentially expressed pathways in high-throughput gene expression studies. Pathway analysis involves fewer tests than differential gene expression analysis, on the order of a few hundred. We discuss and compare methods for...

Gold, David L.; Miecznikowski, Jeffrey C.; Liu, Song

2009-01-01

127

Dynamic analysis for robot arm control  

Science.gov (United States)

Explicit state equations provide detailed analytic insight into the dynamic behavior of a robot arm and facilitate the understanding of the control problem. The analytic strength of explicit state equations is exemplified for a given robot arm. In fact, for the quoted example, the explicit and exact state equations involve considerably less computation than the use of the known most efficient general-purpose computational algorithm for robot arm dynamics.

Bejczy, A. K.

1983-01-01

128

Analysis and control of interleaved Swiss rectifiers  

OpenAIRE

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

129

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

130

Study on Subspace Control Based on Modal Analysis  

Science.gov (United States)

As a new control technique called the subspace control method is developed in an effort to carry out finely tuned control easily and efficiently for a complicated and large-scale mechanical system. In the subspace control method, the minimum and optimum subspace suited for the control specification is extracted from the entire state space by applying the concept of modal analysis, and feedback control based on the modal coordinate is performed in the subspace. The subspace control method takes advantage of the dynamic characteristics of the controlled object in the design of control system. In addition, decreasing the dimension of the controlled object based on the dynamic characteristics leads to simplification of the design of control system, reduction of mechanical overload caused by the control, and a reduction in consumed electric power. In the present study, in order to clarify the fundamental concept, the subspace control method is formulated for swing-up and stabilizing controls of an inverted pendulum system. The effectiveness of the proposed method is verified by numerical simulations and experiments.

Sonobe, Motomichi; Kondou, Takahiro; Sowa, Nobuyuki; Matsuzaki, Kenichiro

131

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

132

Confirmatory Factor Analysis of the Cancer Locus of Control Scale.  

Science.gov (United States)

Conducted a confirmatory factor analysis of the Cancer Locus of Control scale (M. Watson and others, 1990), administered to 543 women with a history of breast cancer. Results support a three-factor model of the scale and support use of the scale to assess control dimensions. (SLD)

Henderson, Jessica W.; Donatelle, Rebecca J.; Acock, Alan C.

2002-01-01

133

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

134

Control of precious metal plating baths using electrogravimetric analysis  

Science.gov (United States)

This paper is an outline of an electrogravimetric method for inventory control of precious metal plating baths. The procedure is meant to be applicable to a plating shop environment to provide in-process control. A short review of procedural techniques for sample preparation and analysis are included. The paper deals with the basic how to approach for developing a practical system of analytical control of precious metal electroplating baths permitting accountability of 99% or greater.

Yelton, W. G.

135

Fluorescence and phosphorescence properties of the low temperature forms of the MAl2Si2O8:Eu2+ (M=Ca, Sr, Ba) compounds  

International Nuclear Information System (INIS)

The fluorescence and phosphorescence properties of Europium-doped MAl2Si2O8 (M=Ca, Sr, Ba) are reinvestigated and discussed on the basis of the propensity of an activator to agglomerate with an oxygen vacancy. Due to a stronger attraction of the anion vacancy towards Eu2+ cations going from BaAl2Si2O8 to SrAl2Si2O8 and CaAl2Si2O8 host lattices, the interpretation of the fluorescence spectra turns out to be less trivial in the Ca and Sr host lattices than in the Ba one and requests the account for Eu2+ cations lying at alkaline-earth sites with or without vacancy in their neighborhood. Phosphorescence in these compounds is highlighted. - Graphical abstract: The Eu2+-doped MAl2Si2O8 (M=Ca, Sr, and Ba) aluminosilicates exhibit a bluish white luminescence, which can last several minutes after the removal of the excitation. The account for Eu2+ cations coupled with defects is required to explain fluorescence spectra

136

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

137

The Application of Control Chart in the Measurement System Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available The effectiveness of the quality improvement depends on the capability of the measurement system to a great extent. Based on the researches of the stability and bias analysis of the measurement system, we analyzed the application of the control chart in the stability and bias analysis of the measurement system, and gave the applied example.

Yueyi Zhang

2009-03-01

138

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)

139

Cations analysis by controlled potential coulometry. I. - Analysis of uranium  

International Nuclear Information System (INIS)

A controlled-potential coulometry for determination of uranium has been carried out. This method is based on the reduction of potassium ferricyanide in the presence of uranyl ions in acid media. Application range and precision of the coulometric method has been determined and applied to the determination of uranium in ores

140

Controllability analysis of modified Petlyuk structures  

Energy Technology Data Exchange (ETDEWEB)

Distillation columns can consume a large portion of energy in chemical industry processes. Integrated Petlyuk columns have been shown to improve energy efficiencies by between 20 and 40 per cent, and thermally coupled distillation columns can serve as an alternative to conventional distillation sequences in multicomponent mixture separation processes. Until recently, operational difficulties have limited the wider introduction of Petlyuk columns in industrial applications. Alternative Petlyuk-type schemes have now been developed to provide improved operation properties. This paper discussed, evaluated, and compared the theoretical control properties of 6 different Petlyuk schemes. Computations were performed using a singular value decomposition (SVD) technique in the frequency domain. Dynamic closed-loop responses for set point tracking, and disturbance rejections were derived in order to support each scheme's theoretical control properties. Results of the comparative evaluation demonstrated that reductions in the number of interconnections and the use of unidirectional flows impacted the dynamic properties of the schemes, and led to operational improvements in thermally coupled distillation sequences. It was concluded that Petyluk properties can be improved through the correction of the bidirectionality of interconnecting streams. 30 refs., 10 tabs., 9 figs.

Tamayo-Galvan, V.E.; Segovia-Hernandez, J.G.; Hernandez, S.; Hernandez, H. [Guanajuato Univ. (Mexico). Faculty of Chemistry

2008-02-15

141

Power system small signal stability analysis and control  

CERN Document Server

Power System Small Signal Stability Analysis and Control presents a detailed analysis of the problem of severe outages due to the sustained growth of small signal oscillations in modern interconnected power systems. The ever-expanding nature of power systems and the rapid upgrade to smart grid technologies call for the implementation of robust and optimal controls. Power systems that are forced to operate close to their stability limit have resulted in the use of control devices by utility companies to improve the performance of the transmission system against commonly occurring power system

Mondal, Debasish; Sengupta, Aparajita

2014-01-01

142

Application of hazard analysis and critical control points in shipbuilding  

Directory of Open Access Journals (Sweden)

Full Text Available The possibility of application of hazard analysis and critical control points (HACCP in the shipbuilding is considered. HACCP definitions are presented; the system origin is described and HACCP principles are characterized. It is noted that HACCP principles accepted nowadays are used only in food industry but cannot be applied in shipbuilding. The suggestions on adaptation and integration of the given principles at realization of shipbuilding projects within risk analysis are given. There has been made a conclusion on the possibility of application of the system and the principles of the hazard analysis and critical control points in shipbuilding under conditions of adaptation of the given system to the shipbuilding project.

Putilina Ekaterina Yurievna

2013-06-01

143

Resonance analysis in parallel voltage-controlled Distributed Generation inverters  

DEFF Research Database (Denmark)

Thanks to the fast responses of the inner voltage and current control loops, the dynamic behaviors of parallel voltage-controlled Distributed Generation (DG) inverters not only relies on the stability of load sharing among them, but subjects to the interactions between the voltage control loops of the inverters and the remaining system dynamics. This paper addresses the later interactions and the consequent resonances through the frequency-domain analysis of the inverters output impedances and the remaining equivalent network impedance. Furthermore, impacts of the virtual output impedance loop and the voltage feedforward loop in the current controller are evaluated based on such an impedance interactions analysis. Simulation results are presented to confirm the validity of the theoretical analysis.

Wang, Xiongfei; Blaabjerg, Frede

2013-01-01

144

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

145

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)

146

Analysis and experimental study of MIMO control in refrigeration system  

International Nuclear Information System (INIS)

For various operating conditions and loads of refrigeration systems, converters are used to change the compressor's speed, and electronic expansion valves are adopted to regulate refrigerant flow rates. The refrigeration system, as a process under control, is a multi-input multi-output (MIMO) and nonlinear complex system. Based on the analysis of fuzzy and neural networks control, a self organized fuzzy neural network controller with the capacity of construction and parameter learning is proposed according to the simplified fuzzy control algorithm and the similarity between structure and function of a counter propagation network (CPN). This controller is easily structured with the feature of fuzzy control, and it also possesses the learning ability of neutral networks. The air cooled refrigeration experimental results show that the present controller can modulate the evaporation pressure and the superheating

147

Analysis and experimental study of MIMO control in refrigeration system  

Energy Technology Data Exchange (ETDEWEB)

For various operating conditions and loads of refrigeration systems, converters are used to change the compressor's speed, and electronic expansion valves are adopted to regulate refrigerant flow rates. The refrigeration system, as a process under control, is a multi-input multi-output (MIMO) and nonlinear complex system. Based on the analysis of fuzzy and neural networks control, a self organized fuzzy neural network controller with the capacity of construction and parameter learning is proposed according to the simplified fuzzy control algorithm and the similarity between structure and function of a counter propagation network (CPN). This controller is easily structured with the feature of fuzzy control, and it also possesses the learning ability of neutral networks. The air cooled refrigeration experimental results show that the present controller can modulate the evaporation pressure and the superheating.

Tian Jian [School of Energy and Power Engineering, Xi' an Jiao Tong University, Xi' an 710049 (China)], E-mail: tjian@mailst.xjtu.edu.cn; Feng Quanke; Zhu Ruiqi [School of Energy and Power Engineering, Xi' an Jiao Tong University, Xi' an 710049 (China)

2008-05-15

148

Analysis and experimental study of MIMO control in refrigeration system  

Energy Technology Data Exchange (ETDEWEB)

For various operating conditions and loads of refrigeration systems, converters are used to change the compressor's speed, and electronic expansion valves are adopted to regulate refrigerant flow rates. The refrigeration system, as a process under control, is a multi-input multi-output (MIMO) and nonlinear complex system. Based on the analysis of fuzzy and neural networks control, a self organized fuzzy neural network controller with the capacity of construction and parameter learning is proposed according to the simplified fuzzy control algorithm and the similarity between structure and function of a counter propagation network (CPN). This controller is easily structured with the feature of fuzzy control, and it also possesses the learning ability of neutral networks. The air cooled refrigeration experimental results show that the present controller can modulate the evaporation pressure and the superheating. (author)

Tian, Jian; Feng, Quanke; Zhu, Ruiqi [School of Energy and Power Engineering, Xi' an Jiao Tong University, Xi' an 710049 (China)

2008-05-15

149

Morphological Component Analysis and Inpainting on the sphere : Application in Physics and Astrophysics  

OpenAIRE

Morphological Component Analysis (MCA) is a new method which takes advantage of the sparse representation of structured data in large overcomplete dictionaries to separate features in the data based on the diversity of their morphology. It is an efficient technique in such problems as separating an image into texture and piecewise smooth parts or for inpainting applications. The MCA algorithm consists of an iterative alternating projection and thresholding scheme, using a successively decreas...

Abrial, P.; Moudden, Y.; Starck, J. -l; Afeyan, B.; Bobin, J.; Nguyen, Mai? K.; Fadili, Jalal

2007-01-01

150

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

151

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.

Szederkényi, G.; Kristensen, Niels Rode

2002-01-01

152

INSIGHT: an integrated scoping analysis tool for in-core fuel management of PWR  

International Nuclear Information System (INIS)

An integrated software tool for scoping analysis of in-core fuel management, INSIGHT, has been developed to automate the scoping analysis and to improve the fuel cycle cost using advanced optimization techniques. INSIGHT is an interactive software tool executed on UNIX based workstations that is equipped with an X-window system. INSIGHT incorporates the GALLOP loading pattern (LP) optimization module that utilizes hybrid genetic algorithms, the PATMAKER interactive LP design module, the MCA multicycle analysis module, an integrated database, and other utilities. Two benchmark problems were analyzed to confirm the key capabilities of INSIGHT: LP optimization and multicycle analysis. The first was the single cycle LP optimization problem that included various constraints. The second one was the multicycle LP optimization problem that includes the assembly burnup limitation at rod cluster control (RCC) positions. The results for these problems showed the feasibility of INSIGHT for the practical scoping analysis, whose work almost consists of LP generation and multicycle analysis. (author)

153

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

154

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

155

REVIEW OF NRC APPROVED DIGITAL CONTROL SYSTEMS ANALYSIS  

International Nuclear Information System (INIS)

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

156

Analysis of design control values for TEP  

Energy Technology Data Exchange (ETDEWEB)

The Tokamak Exhaust Processing (TEP) Performance Requirements Report (USITER-13201-TD0005-R00), date May 29, 2007 defined feed sources for TEP quantities and approximate flow rate of gases from these individual sources. In addition, the report identified the approximate periods of time (during Burn and Dwell, 'Silent Shift', etc.) that these gases would be transferred to TEP. This report did not take into account the detailed, time dependent, sequencing options for receiving gases from these feed sources. Sequencing is critical in defining the actual design basis values (flow rates, etc.) for TEP. This report analyzes the time dependent sequencing of feed flows to TEP and defines the ,design basis values. This analysis is based on the values presented in the TEP Performance Requirements Report (TEP PRR), and indicates that the ITER Burn and Dwell, Silent Shift Following 16 hours of Burn and Dwell, Glow Discharge Cleaning (GDC), and Silent Shift following 100 hours of GDC scenarios are the limiting scenarios from which the design basis values will be defined.

Carlson, Bryan J [Los Alamos National Laboratory

2008-01-01

157

Analysis of design control values for TEP  

International Nuclear Information System (INIS)

The Tokamak Exhaust Processing (TEP) Performance Requirements Report (USITER-13201-TD0005-R00), date May 29, 2007 defined feed sources for TEP quantities and approximate flow rate of gases from these individual sources. In addition, the report identified the approximate periods of time (during Burn and Dwell, 'Silent Shift', etc.) that these gases would be transferred to TEP. This report did not take into account the detailed, time dependent, sequencing options for receiving gases from these feed sources. Sequencing is critical in defining the actual design basis values (flow rates, etc.) for TEP. This report analyzes the time dependent sequencing of feed flows to TEP and defines the ,design basis values. This analysis is based on the values presented in the TEP Performance Requirements Report (TEP PRR), and indicates that the ITER Burn and Dwell, Silent Shift Following 16 hours of Burn and Dwell, Glow Discharge Cleaning (GDC), and Silent Shift following 100 hours of GDC scenarios are the limiting scenarios from which the design basis values will be defined.

158

Supercritical carbon dioxide cycle control analysis  

International Nuclear Information System (INIS)

This report documents work carried out during FY 2008 on further investigation of control strategies for supercritical carbon dioxide (S-CO2) Brayton cycle energy converters. The main focus of the present work has been on investigation of the S-CO2 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-CO2 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-CO2 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-CO2 Brayton cycle with a decaying liquid metal coolant flow to the Pb-to-CO2 heat exchangers and temperatures reflsub> 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-CO2 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-CO2 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-CO2 cycle investigations to be carried out, the ANL Plant Dynamics Code for the S-CO2 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-CO2 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 the dynamic simulation

159

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)

160

Use of task analysis in control room evaluations  

International Nuclear Information System (INIS)

Responding to recently formulated regulatory requirements, the BWR Owners' Group, working in conjunction with General Electric, has formulated a method for performing human factors design reviews of nuclear power plant control rooms. This process incorporates task analyses to analyze operational aspects of panel layout and design. Correlation of operator functions defined by emergency procedures against required controls and displays has proven successful in identifying instrumentation required in the control room to adequately respond to transient conditions, and in evaluating the effectiveness of panel design and physical arrangement. Extensions of the analysis have provided information on operator response paths, frequency of use of instruments, and control room layout. The techniques used were based on a need to identify primary controls and indications required by the operator in performing each step of the applicable procedure. The relative locations of these instruments were then analyzed for information on the adequacy of the control room design for those conditions

161

Stability Analysis Method for Fuzzy Control Systems Dedicated Controlling Nonlinear Processes  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a new stability analysis method for nonlinear processes withTakagi-Sugeno (T-S fuzzy logic controllers (FLCs. The design of the FLCs is based onheuristic fuzzy rules. The stability analysis of these fuzzy control systems is performed usingLaSalle’s invariant set principle with non-quadratic Lyapunov candidate function. Thispaper proves that if the derivative of Lyapunov function is negative semi-definite in theactive region of each fuzzy rule, then the overall system will be asymptotically stable in thesense of Lyapunov (ISL. The stability theorem suggested in the paper ensures sufficientstability conditions for fuzzy control systems controlling a class of nonlinear processes. Theend of the paper contains an illustrative example that describes an application of thestability analysis method.

Marius-Lucian Tomescu

2007-10-01

162

Unified power flow controller: Modeling, stability analysis, control strategy and control system design  

Science.gov (United States)

Unified power flow controller (UPFC) has been the most versatile Flexible AC Transmission System (FACTS) device due to its ability to control real and reactive power flow on transmission lines while controlling the voltage of the bus to which it is connected. UPFC being a multi-variable power system controller it is necessary to analyze its effect on power system operation. To study the performance of the UPFC in damping power oscillations using PSCAD-EMTDC software, a de-coupled control system has been designed for the shunt inverter to control the UPFC bus voltage and the DC link capacitor voltage. The series inverter of a UPFC controls the real power flow in the transmission line. One problem associated with using a high gain PI controller (used to achieve fast control of transmission line real power flow) for the series inverter of a UPFC to control the real power flow in a transmission line is the presence of low damping. This problem is solved in this research by using a fuzzy controller. A method to model a fuzzy controller in PSCAD-EMTDC software has also been described. Further, in order to facilitate proper operation between the series and the shunt inverter control system, a new real power coordination controller has been developed and its performance was evaluated. The other problem concerning the operation of a UPFC is with respect to transmission line reactive power flow control. Step changes to transmission line reactive power references have significant impact on the UPFC bus voltage. To reduce the adverse effect of step changes in transmission line reactive power references on the UPFC bus voltage, a new reactive power coordination controller has been designed. Transient response studies have been conducted using PSCAD-EMTDC software to show the improvement in power oscillation damping with UPFC. These simulations include the real and reactive power coordination controllers. Finally, a new control strategy has been proposed for UPFC. In this proposed control strategy, the shunt inverter controls the DC link capacitor voltage and the transmission line reactive power flow. The series inverter controls the transmission line real power flow and the UPFC bus voltage. PSCAD-EMTDC simulations have been conducted to show the viability of the control strategy in damping power oscillations.

Sreenivasachar, Kannan

2001-07-01

163

Moving shape analysis and control applications to fluid structure interactions  

CERN Document Server

Problems involving the evolution of two- and three-dimensional domains arise in many areas of science and engineering. Emphasizing an Eulerian approach, Moving Shape Analysis and Control: Applications to Fluid Structure Interactions presents valuable tools for the mathematical analysis of evolving domains. The book illustrates the efficiency of the tools presented through different examples connected to the analysis of noncylindrical partial differential equations (PDEs), such as Navier-Stokes equations for incompressible fluids in moving domains. The authors first provide all of the details of existence and uniqueness of the flow in both strong and weak cases. After establishing several important principles and methods, they devote several chapters to demonstrating Eulerian evolution and derivation tools for the control of systems involving fluids and solids. The book concludes with the boundary control of fluid-structure interaction systems, followed by helpful appendices that review some of the advanced m...

Moubachir, Marwan

2006-01-01

164

System analysis for optimal control of a wastewater treatment benchmark.  

Science.gov (United States)

The paper presents an analysis and optimisation of a wastewater treatment benchmark. The benchmark is a simulation environment defining a plant layout, simulation model, influent data, test procedures and evaluating criteria that should be used for comparing different control strategies. In this paper an analysis of the benchmark which addresses the influences of potential manipulated variables on control performance under different operating conditions is presented. In the study optimisation is used to define the optimal values of the manipulated variables under constant as well as dynamic influent conditions. The results indicate that such an analysis and optimisation give important information about the manipulated variables under varying influent conditions and consequently about possible control strategies. PMID:11385848

Vrecko, D; Hvala, N; Kocijan, J; Zec, M

2001-01-01

165

REACTOR ANALYSIS AND VIRTUAL CONTROL ENVIRONMENT (RAVEN) FY12 REPORT  

Energy Technology Data Exchange (ETDEWEB)

RAVEN is a complex software tool that will have tasks spanning from being the RELAP-7 user interface, to using RELAP-7 to perform Risk Informed Safety Characterization (RISMC), and to controlling RELAP-7 calculation execution. The goal of this document is to: 1. Highlight the functional requirements of the different tasks of RAVEN 2. Identify shared functions that could be aggregate in modules so to obtain a minimal software redundancy and maximize software utilization. RAVEN is in fact a software framework that will allow exploiting the following functionalities: • Derive and actuate the control logic required to: o Simulate the plant control system o Simulate the operator (procedure guided) actions o Perform Monte Carlo sampling of random distributed events o Perform event three based analysis • Provide a GUI to: o Input a plant description to RELAP-7 (component, control variable, control parameters) o Concurrent monitoring of Control Parameters o Concurrent alteration of control parameters • Provide Post Processing data mining capability based on o Dimensionality reduction o Cardinality reduction In this document it will be shown how an appropriate mathematical formulation of the control logic and probabilistic analysis leads to have most of the software infrastructure leveraged between the two main tasks. Further, this document will go through the development accomplished this year, including simulation results, and priorities for the next years development

Cristian Rabiti; Andrea Alfonsi; Joshua Cogliati; Diego Mandelli; Robert Kinoshita

2012-09-01

166

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

167

Concurrent analysis of choice and control in childbirth  

OpenAIRE

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

168

Contributions to fuzzy polynomial techniques for stability analysis and control  

OpenAIRE

The present thesis employs fuzzy-polynomial control techniques in order to improve the stability analysis and control of nonlinear systems. Initially, it reviews the more extended techniques in the field of Takagi-Sugeno fuzzy systems, such as the more relevant results about polynomial and fuzzy polynomial systems. The basic framework uses fuzzy polynomial models by Taylor series and sum-of-squares techniques (semidefinite programming) in order to obtain stability guarantees...

Pitarch Pe?rez, Jose? Luis

2014-01-01

169

Stability analysis and control design of spatially developing flows  

OpenAIRE

Methods in hydrodynamic stability, systems and control theory are applied to spatially developing flows, where the flow is not required to vary slowly in the streamwise direction. A substantial part of the thesis presents a theoretical framework for the stability analysis, input-output behavior, model reduction and control design for fluid dynamical systems using examples on the linear complex Ginzburg-Landau equation. The framework is then applied to high dimensional systems arising from the...

Bagheri, Shervin

2008-01-01

170

Multi-intersection Traffic Light Control Using Infinitesimal Perturbation Analysis  

OpenAIRE

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. Th...

Geng, Yanfeng; Cassandras, Christos G.

2012-01-01

171

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)

172

Application of hazard analysis and critical control points in shipbuilding  

OpenAIRE

The possibility of application of hazard analysis and critical control points (HACCP) in the shipbuilding is considered. HACCP definitions are presented; the system origin is described and HACCP principles are characterized. It is noted that HACCP principles accepted nowadays are used only in food industry but cannot be applied in shipbuilding. The suggestions on adaptation and integration of the given principles at realization of shipbuilding projects within risk analysis are given. There ha...

Putilina Ekaterina Yurievna

2013-01-01

173

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.

174

Economic Analysis of Corrosion Control In Petroleum Refineries  

OpenAIRE

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

175

Security Analysis of a Wireless Quadruple Tank Control System  

OpenAIRE

The main emphasis of this Master Thesis is the analysis of the effect of malicious deception attacks applied to a real process, in this case a scale model of a water distribution system made up of four interconnected water tanks and two pumps to control the water levels. The process model is derived, followed by the design and  est of three kinds of controllers: LQG, PI and PI robustified with the Glover-McFarlane method. Later, the performance of the closed loop system with these controller...

Forment Navarro, Albert

2011-01-01

176

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

177

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

178

Coherent-control of linear signals: Frequency-domain analysis  

OpenAIRE

The dependence of various types of linear signals on the phase profile of broadband optical pulses is examined using fundamental time translation invariance symmetry of multipoint correlation functions. The frequency-domain wave-mixing analysis presented here unifies several arguments made earlier with respect to the conditions whereby coherent control schemes may be used.

Mukamel, Shaul

2013-01-01

179

Method of Non-optimum Analysis on Risk Control System  

Directory of Open Access Journals (Sweden)

Full Text Available This paper discusses in detail the theory of non-optimum analysis on risk management systems. It points out that the main problem of exploring an indefinite system’ optimum lies in the lack of non- optimum analysis on the risk management system. The paper establishes the syndrome and empirical analysis based on the non-optimum category of the risk. At the same time, through the concept of intervenient optimum, it analyzes the actual significance of the optimum of the risk control. Based on non-optimum analysis, it puts out the academic idea of extension risk analysis. At the same time, it also puts forward the non-optimum measurement of the risk system along with non-optimum tracing and self-organization of the risk systems.

Zengtang Qu

2009-06-01

180

Analysis of the Body Control System Related to Mental Workload  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we present a model?based analysis of the standing posture control mechanism with consideration to mental workload and the physiological features of sensory feedback. It has been known that standing posture control is not performed autonomously or unconsciously but is affected by “working memory” [1]. In order to investigate how mental workload in working memory influences standing posture control, we consider the feedback groups in the standing posture control mechanism which include the viscoelastic characteristics of the musculoskeletal system and sensory feedback. We use a centre of pressure (COP?based tracking task to investigate the influence of mental workload on voluntary (tracking movement. Maurer?Peterka’s model is applied to analyse the standing posture control mechanism, with respect to a change in the internal processes. The simulation results show the relationship of the feedback gain and its delay from the central nervous system with the standing posture control performance. The proposed model?based scheme provides a comprehensive view for physiological data analysis of human body movement in relation to mental workload.

Seiji Naito

2012-12-01

181

Data Analysis  

Energy Technology Data Exchange (ETDEWEB)

Analysis of the material protection, control, and accountability (MPC&A) system is necessary to understand the limits and vulnerabilities of the system to internal threats. A self-appraisal helps the facility be prepared to respond to internal threats and reduce the risk of theft or diversion of nuclear material. The material control and accountability (MC&A) system effectiveness tool (MSET) fault tree was developed to depict the failure of the MPC&A system as a result of poor practices and random failures in the MC&A system. It can also be employed as a basis for assessing deliberate threats against a facility. MSET uses fault tree analysis, which is a top-down approach to examining system failure. The analysis starts with identifying a potential undesirable event called a 'top event' and then determining the ways it can occur (e.g., 'Fail To Maintain Nuclear Materials Under The Purview Of The MC&A System'). The analysis proceeds by determining how the top event can be caused by individual or combined lower level faults or failures. These faults, which are the causes of the top event, are 'connected' through logic gates. The MSET model uses AND-gates and OR-gates and propagates the effect of event failure using Boolean algebra. To enable the fault tree analysis calculations, the basic events in the fault tree are populated with probability risk values derived by conversion of questionnaire data to numeric values. The basic events are treated as independent variables. This assumption affects the Boolean algebraic calculations used to calculate results. All the necessary calculations are built into the fault tree codes, but it is often useful to estimate the probabilities manually as a check on code functioning. The probability of failure of a given basic event is the probability that the basic event primary question fails to meet the performance metric for that question. The failure probability is related to how well the facility performs the task identified in that basic event over time (not just one performance or exercise). Fault tree calculations provide a failure probability for the top event in the fault tree. The basic fault tree calculations establish a baseline relative risk value for the system. This probability depicts relative risk, not absolute risk. Subsequent calculations are made to evaluate the change in relative risk that would occur if system performance is improved or degraded. During the development effort of MSET, the fault tree analysis program used was SAPHIRE. SAPHIRE is an acronym for 'Systems Analysis Programs for Hands-on Integrated Reliability Evaluations.' Version 1 of the SAPHIRE code was sponsored by the Nuclear Regulatory Commission in 1987 as an innovative way to draw, edit, and analyze graphical fault trees primarily for safe operation of nuclear power reactors. When the fault tree calculations are performed, the fault tree analysis program will produce several reports that can be used to analyze the MPC&A system. SAPHIRE produces reports showing risk importance factors for all basic events in the operational MC&A system. The risk importance information is used to examine the potential impacts when performance of certain basic events increases or decreases. The initial results produced by the SAPHIRE program are considered relative risk values. None of the results can be interpreted as absolute risk values since the basic event probability values represent estimates of risk associated with the performance of MPC&A tasks throughout the material balance area (MBA). The RRR for a basic event represents the decrease in total system risk that would result from improvement of that one event to a perfect performance level. Improvement of the basic event with the greatest RRR value produces a greater decrease in total system risk than improvement of any other basic event. Basic events with the greatest potential for system risk reduction are assigned performance improvement values, and new fault tree calculations show the i

Powell, Danny H [ORNL; Elwood Jr, Robert H [ORNL

2011-01-01

182

Rapid and accurate control rod calibration measurement and analysis  

International Nuclear Information System (INIS)

In order to reduce the time needed to perform control rod calibrations and improve the accuracy of the results, a technique for a measurement, analysis, and tabulation of integral rod worths has been developed. A single series of critical rod positions are determined at constant low power to reduce the waiting time between positive period measurements and still assure true stable reactor period data. Reactivity values from positive period measurements and control rod drop measurements are used as input data for a non-linear fit to the expected control rod integral worth shape. With this method, two control rods can be calibrated in about two hours, and integral and differential calibration tables for operator use are printed almost immediately. Listings of the BASIC computer programs for the non-linear fitting and calibration table preparation are provided. (author)

183

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

184

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)

185

Design and Analysis of Bayesian Model Predictive Controller  

Directory of Open Access Journals (Sweden)

Full Text Available In this article, a novel predictive controller based on a Bayesian inferring nonlinear model (BMPC is presented and analyzed. In the construction of the BMPC, the Bayesian inferring model is selected as the predictive model with the characteristics of on-line tracing ability to the actual controlled object. The nonlinear programming method called the steepest gradient is set as the receding horizon optimization algorithm of the BMPC. The on-line controller output is obtained using this method. The convergence analysis of the proposed BMPC is given and the examples (nonminimum phase and nonlinear objects are selected to validate the performance of the BMPC. The simulation results show that with the help of the presented BMPC algorithm, the closed loop control system demonstrates the abilities of anti-disturbance and robustness.

Yijian Liu

2014-07-01

186

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

187

Compliance or good control and accountability  

Energy Technology Data Exchange (ETDEWEB)

DOE Orders and draft orders for nuclear material control and accountability address the need for a complete material control and accountability (MC&A) program for all DOE contractors processing, using, and/or storing nuclear materials. These orders also address performance as well as compliance issues. Very often the existence of a program or an element of a program satisfies the compliance aspect of DOE requirements. The concept of performance requirements is new and requires new thinking with all of the elements of the MC&A program. The contractor is so accustomed to compliance with DOE requirements that dealing with performance is not well understood. In this paper I will address the receptiveness of performance requirements by the contractor. Auditing for performance is also a new concept and has not been implemented. The contractor will have to learn how to measure the performance of the MC&A program and be able to demonstrate a certain level of performance to the oversight organization. This paper will contain a discussion of a well organized MC&A program, the compliance issues associated with the program, the performance criteria associated with the program, and how to audit such a program.

Erkkila, B.H.

1993-08-01

188

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

Science.gov (United States)

... false Hazard Analysis and Critical Control...Section 120.8 Food and Drugs FOOD...CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL...whenever a hazard analysis reveals one or more food hazards...

2010-04-01

189

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

190

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

OpenAIRE

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 ...

Noskievic?ova?, D.

2009-01-01

191

Parameter Estimation Analysis for Hybrid Adaptive Fault Tolerant Control  

Science.gov (United States)

Research efforts have increased in recent years toward the development of intelligent fault tolerant control laws, which are capable of helping the pilot to safely maintain aircraft control at post failure conditions. Researchers at West Virginia University (WVU) have been actively involved in the development of fault tolerant adaptive control laws in all three major categories: direct, indirect, and hybrid. The first implemented design to provide adaptation was a direct adaptive controller, which used artificial neural networks to generate augmentation commands in order to reduce the modeling error. Indirect adaptive laws were implemented in another controller, which utilized online PID to estimate and update the controller parameter. Finally, a new controller design was introduced, which integrated both direct and indirect control laws. This controller is known as hybrid adaptive controller. This last control design outperformed the two earlier designs in terms of less NNs effort and better tracking quality. The performance of online PID has an important role in the quality of the hybrid controller; therefore, the quality of the estimation will be of a great importance. Unfortunately, PID is not perfect and the online estimation process has some inherited issues; the online PID estimates are primarily affected by delays and biases. In order to ensure updating reliable estimates to the controller, the estimator consumes some time to converge. Moreover, the estimator will often converge to a biased value. This thesis conducts a sensitivity analysis for the estimation issues, delay and bias, and their effect on the tracking quality. In addition, the performance of the hybrid controller as compared to direct adaptive controller is explored. In order to serve this purpose, a simulation environment in MATLAB/SIMULINK has been created. The simulation environment is customized to provide the user with the flexibility to add different combinations of biases and delays to the explored derivatives. Biases were considered in the range -500% to 500% and delays in the range 0.5 to 40 seconds. The stability and control derivatives considered in this research effort are a combination of decoupled derivatives in the three channels, longitudinal, lateral, and directional. Numerous simulation scenarios and flight conditions are considered to provide more credibility to the obtained results. In addition, a statistical analysis has been conducted to assess the results. The performance of the control laws has been evaluated in terms of the integral of the error in tracking the three desired angular rates, pitch, roll, and yaw. In addition, the effort of the neural networks exerted to compensate for tracking errors is considered in the analysis as well. The results show that in order to obtain reliable estimates for the investigated derivatives, the estimator needs to generate values with less than five seconds delay. In addition, derivatives estimates are within 50% or -15% off the exact values. Moreover, the importance of updating derivatives depends on the maneuver scenario and the flight condition. The estimation process at quasi-steady state conditions provides reliable estimates as opposed to estimation during fast dynamic changes; also, the estimation process has better performance at large rate of change of derivatives values.

Eshak, Peter B.

192

Intelligent control of HVAC systems. Part II: perceptron performance analysis  

Directory of Open Access Journals (Sweden)

Full Text Available This is the second part of a paper on intelligent type control of Heating, Ventilating, and Air-Conditioning (HVAC systems. The whole study proposes a unified approach in the design of intelligent control for such systems, to ensure high energy efficiency and air quality improving. In the first part of the study it is considered as benchmark system a single thermal space HVAC system, for which it is assigned a mathematical model of the controlled system and a mathematical model(algorithm of intelligent control synthesis. The conception of the intelligent control is of switching type, between a simple neural network, a perceptron, which aims to decrease (optimize a cost index,and a fuzzy logic component, having supervisory antisaturating role for neuro-control. Based on numerical simulations, this Part II focuses on the analysis of system operation in the presence only ofthe neural control component. Working of the entire neuro-fuzzy system will be reported in a third part of the study.

Ioan URSU

2013-09-01

193

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

194

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

195

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

196

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

197

Analysis of control rod drop transients for pressurized water reactors  

International Nuclear Information System (INIS)

A methodology has been developed to analyze control rod drop transients in PWR's without a turbine runback or a rod withdrawal block which takes credit for a high negative neutron flux rate trip. This methodology addresses both the overall plant response and the detailed core thermal hydraulics to predict conservative minimum thermal margins throughout the event. This method has been applied to the two Prairie Island Units to demonstrate that existing operating restrictions for the control rod drive system are not necessary to preclude fuel damage. A reduced setpoint for the rate trip relative to current limiting Technical Specifications was assumed in the analysis to minimize the consequences of this event

198

Impact of JIT on Quality Control Cost: A Sensitivity Analysis  

OpenAIRE

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 ...

Vikas Kumar,

2014-01-01

199

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

200

Development, analysis, and control of the inductor-converter bridge  

International Nuclear Information System (INIS)

The inductor-converter bridge (ICB) is a solid state dc-ac-dc power converter system for bidirectional, controllable, energy transfer between two high Q magnet coils. The ICB is suitable for supplying large pulsed power to such magnets as the superconducting equilibrium field (EF) coil of the proposed tokamak power reactors, from another superconducting energy storage coil. This report presents work on the analysis and control of the ICB system. The process of energy transfer between the coils is explained on the basis of a simple one line equivalent circuit. This circuit is the topological dual of the one line diagram of the nonsalient pole synchoronous generator, connected to the infinite bus through its synchronous reactance. The changes in the average power, average coil currents, and voltages, as functions of time, are calculated by the conventional Fourier method of analysis

201

Quality control of Citri reticulatae pericarpium: exploratory analysis and discrimination.  

Science.gov (United States)

Extracts of Citri reticulatae pericarpium (PCR) are commonly used in the Traditional Chinese Medicine. The quality control of PCR is currently performed by single marker analysis, which can hardly describe the complexity of such natural samples. In this study, a fingerprint methodology for PCR based on high-performance liquid chromatography (HPLC) was developed and validated. A total of 69 fingerprints of authenticated PCR samples, commercial PCR samples, mixed peel samples, and other Citrus peels were recorded. Exploratory data analysis allowed optimizing the extraction procedure and detecting mixed peel samples. Once the optimizations were performed and the method validated, discrimination between the authentic PCR samples and all other samples was performed by p-Discriminant Partial Least Squares. The established model was able to differentiate between classes with a high reliability for each sample. Furthermore, evaluation of the score and loading plots of the model indicated nobiletin, tangeretin, naringin and hesperidin as important markers for the quality control of PCR. PMID:21962354

Tistaert, Christophe; Thierry, Line; Szandrach, Andrzej; Dejaegher, B; Fan, Guorong; Frédérich, Michel; Vander Heyden, Yvan

2011-10-31

202

Comparative analysis of PSO algorithms for PID controller tuning  

Science.gov (United States)

The active magnetic bearing(AMB) suspends the rotating shaft and maintains it in levitated position by applying controlled electromagnetic forces on the rotor in radial and axial directions. Although the development of various control methods is rapid, PID control strategy is still the most widely used control strategy in many applications, including AMBs. In order to tune PID controller, a particle swarm optimization(PSO) method is applied. Therefore, a comparative analysis of particle swarm optimization(PSO) algorithms is carried out, where two PSO algorithms, namely (1) PSO with linearly decreasing inertia weight(LDW-PSO), and (2) PSO algorithm with constriction factor approach(CFA-PSO), are independently tested for different PID structures. The computer simulations are carried out with the aim of minimizing the objective function defined as the integral of time multiplied by the absolute value of error(ITAE). In order to validate the performance of the analyzed PSO algorithms, one-axis and two-axis radial rotor/active magnetic bearing systems are examined. The results show that PSO algorithms are effective and easily implemented methods, providing stable convergence and good computational efficiency of different PID structures for the rotor/AMB systems. Moreover, the PSO algorithms prove to be easily used for controller tuning in case of both SISO and MIMO system, which consider the system delay and the interference among the horizontal and vertical rotor axes.

Štimac, Goranka; Braut, Sanjin; Žiguli?, Roberto

2014-09-01

203

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

204

Passivity In Analysis Of Robustness Of A Control System  

Science.gov (United States)

Robustness margin (measure of degree of passivity) defined. Paper presents new approach to analysis of stability of multivariable feedforward-and-feedback control system consisting of exponentially stable linear time-invariant (LTI) feedforward subsystem and nonlinear time-varying (NTV) or dynamic feedback subsystem. New method based on notion of passivity, quantified by robustness margin. Margin provides bound on magnitudes of perturbations, below which perturbations will not make system unstable.

Wen, John Ting-Yung

1989-01-01

205

ANALYSIS OF SOLUTIONS FOR THE CONTROL OF THE UNFINISHED PRODUCTION  

OpenAIRE

This research describes potential solutions aplicable to control work in progress in Production Company. Analysis of the current state showed weaknesses. These are manifesting as bad, inaccurate and old – dated data on work in progress. Briefly are described the following technologies: RFID, bar code and voice recognition. The concept of the new system for data collecting, based on presented technologies is proposed. We estimated that investment in new data collecting system would return sh...

Bratus?a, Bojan

2009-01-01

206

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)

207

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

208

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

209

SISO extended predictive control: implementation and robust stability analysis.  

Science.gov (United States)

The proposed algorithm of extended predictive control (EPC) represents an exact method for removing the ill-conditioning in the system matrix by developing a unique weighting structure for any control horizon. The main feature of the EPC algorithm is that it uses the condition number of the system matrix to evaluate a single tuning parameter that provides a specified closed-loop response. Robust analysis demonstrated that EPC is more robust in comparison with move-suppressed and m-shifted predictive controllers in all aspects of process variation in gain, delay, and time-constant ratios. Tuning of EPC is effective and simple since there is a direct relationship between closed-loop performance and its tuning parameter. PMID:16856634

Abu-Ayyad, M; Dubay, R; Kember, G

2006-07-01

210

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

211

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

212

Quality Assurance and Control in Laboratory using Neutron Activation Analysis  

International Nuclear Information System (INIS)

In accordance with the increment of international trade associated with the worldwide globalization, the importance of quality assurance and control for the commodity produced from one's own country has been stressed. ISO (International Organization for Standards) defines quality control as 'the operational techniques and activities that are used to fulfill the requirements for quality'. Since 1996, the HANARO research reactor in the Korea Atomic Energy Research Institute has been operated thereafter initial critical operation on April 1995. Neutron activation analysis system and applied techniques which is one of a nuclear analytical technologies using reactor neutrons has been developed for user's supporting and the establishment of the quality system for a measurement and analysis, testing and inspection was implemented successfully. On the basis of the qualified NAA system, the test and measurement of more than 1500 samples which is requested from 30 organizations including industrial companies, universities and institutes carried out in NAA laboratory annually. Moreover, as the goal of mutual recognition agreement (MRA) which can be removed a technical barrier in international trade, the objectivity and the confidence of analytical quality in NAA laboratory became established through the installation of international accreditation system by implementing analytical quality system in accordance with international standards in 2001. The aim of the report was to summarize the technical management of introduction, methods and the results for a quality control and assurance which should be performed in NAA technique using the HANARO research reactor. The report will help building up effective quality control strategy in the future

213

Performance Analysis and FPGA Implementation of Digital PID Controller for Speed Control of DC Motor  

OpenAIRE

This paper deals with the performance analysis and implementation of PID(Proportional-Integral-Derivative) Controller on FPGA platform.The hardware implementation has been done on Xilinx Spartan 3E FPGA board.The software implementation has been done using Xilinx ISE 8.1i as a tool and simulation is performed using ModelSim 5.4a as a simulator.The PWM signal is generated by FPGA board,which further given to dc motor for its speed control. A new technique has been introduced for the generat...

Charul Agarwal; Ashutosh Gupta; Haneet Rana

2013-01-01

214

An analysis of en route controller-pilot voice communications  

Science.gov (United States)

The purpose of this analysis was to examine current pilot-controller communication practices in the en route environment. Forty-eight hours of voice tapes from eight different Air Route Traffic Control Centers (ARTCC's) were examined. There were 5,032 controller-to-pilot transmissions and 3,576 clearances (e.g., instructions to maneuver or change radio frequencies, routing changes, etc.) in this sample. The complexity of the clearance (i.e., the number of pieces of information) was examined and the number of erroneous readbacks and pilot requests for repeats were analyzed as a function of clearance complexity. Pilot acknowledgements were also analyzed; the numbers of full and partial readbacks, and acknowledgements only (i.e., 'roger') were tallied. Fewer than one percent of the clearances resulted in communications errors. Among the error factors examined were the following: complexity of the clearance, type of acknowledgement, use of call sign in the acknowledgement, type of information in error, and whether or not the controller responded to the readback error. Instances in which the controller contacted the aircraft with one call sign and the pilot acknowledged the transmission with another call sign were also examined. The report concludes with recommendations to further reduce the probability of communication problems.

Cardosi, Kim M.

1993-03-01

215

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

216

Arms control verification costs: the need for a comparative analysis  

International Nuclear Information System (INIS)

The end of the Cold War era has presented practitioners and analysts of international non-proliferation, arms control and disarmament (NACD) the opportunity to focus more intently on the range and scope of NACD treaties and their verification. Aside from obvious favorable and well-publicized developments in the field of nuclear non-proliferation, progress also has been made in a wide variety of arenas, ranging from chemical and biological weapons, fissile material, conventional forces, ballistic missiles, to anti-personnel landmines. Indeed, breaking from the constraints imposed by the Cold War United States-Soviet adversarial zero-sum relationship that impeded the progress of arms control, particularly on a multilateral level, the post Cold War period has witnessed significant developments in NACD commitments, initiatives, and implementation. The goals of this project - in its final iteration - will be fourfold. First, it will lead to the creation of a costing analysis model adjustable for uses in several current and future arms control verification tasks. Second, the project will identify data accumulated in the cost categories outlined in Table 1 in each of the five cases. By comparing costs to overall effectiveness, the application of the model will demonstrate desirability in each of the cases (see Chart 1). Third, the project will identify and scrutinize 'political costs' as well as real expenditures and investment in the verification regimes (see Chart 2). And,e verification regimes (see Chart 2). And, finally, the project will offer some analysis on the relationship between national and multilateral forms of arms control verification, as well as the applicability of multilateralism as an effective tool in the verification of international non-proliferation, arms control, and disarmament agreements. (author)

217

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

218

Gene set control analysis predicts hematopoietic control mechanisms from genome-wide transcription factor binding data  

OpenAIRE

Transcription factors are key regulators of both normal and malignant hematopoiesis. Chromatin immunoprecipitation (ChIP) coupled with high-throughput sequencing (ChIP-Seq) has become the method of choice to interrogate the genome-wide effect of transcription factors. We have collected and integrated 142 publicly available ChIP-Seq datasets for both normal and leukemic murine blood cell types. In addition, we introduce the new bioinformatic tool Gene Set Control Analysis (GSCA). GSCA predicts...

Joshi, Anagha; Hannah, Rebecca; Diamanti, Evangelia; Go?ttgens, Berthold

2013-01-01

219

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.

Zhou, Qian; Su, Xiaoquan; Ning, Kang

2014-11-01

220

Orthogonal fuzzy neighborhood discriminant analysis for multifunction myoelectric hand control.  

Science.gov (United States)

Developing accurate and powerful electromyogram (EMG) driven prostheses controllers that can provide the amputees with effective control on their artificial limbs, has been the focus of a great deal of research in the past few years. One of the major challenges in such research is extracting an informative subset of features that can best discriminate between the different forearm movements. In this paper, a new dimensionality reduction method, referred to as orthogonal fuzzy neighborhood discriminant analysis (OFNDA), is proposed as a response to such a challenge. Unlike existing attempts in fuzzy linear discriminant analysis, the objective of the proposed OFNDA is to minimize the distance between samples that belong to the same class and maximize the distance between the centers of different classes, while taking into account the contribution of the samples to the different classes. The proposed OFNDA is validated on EMG datasets collected from seven subjects performing a range of 5 to 10 classes of forearm movements. Practical results indicate the significance of OFNDA in comparison to many other feature projection methods (including locality preserving and uncorrelated variants of discriminant analysis) with accuracies ranging from 97.66% to 87.84% for 5 to 10 classes of movements, respectively, using only two EMG electrodes. PMID:20172801

Khushaba, Rami N; Al-Ani, Ahmed; Al-Jumaily, Adel

2010-06-01

221

Evaluation of dairy effluent management options using multiple criteria analysis.  

Science.gov (United States)

This article describes how options for managing dairy effluent on the Lower Murray River in South Australia were evaluated using multiple criteria analysis (MCA). Multiple criteria analysis is a framework for combining multiple environmental, social, and economic objectives in policy decisions. At the time of the study, dairy irrigation in the region was based on flood irrigation which involved returning effluent to the river. The returned water contained nutrients, salts, and microbial contaminants leading to environmental, human health, and tourism impacts. In this study MCA was used to evaluate 11 options against 6 criteria for managing dairy effluent problems. Of the 11 options, the MCA model selected partial rehabilitation of dairy paddocks with the conversion of remaining land to other agriculture. Soon after, the South Australian Government adopted this course of action and is now providing incentives for dairy farmers in the region to upgrade irrigation infrastructure and/or enter alternative industries. PMID:18193318

Hajkowicz, Stefan A; Wheeler, Sarah A

2008-04-01

222

Spectroscopic analysis technique for arc-welding process control  

Science.gov (United States)

The spectroscopic analysis of the light emitted by thermal plasmas has found many applications, from chemical analysis to monitoring and control of industrial processes. Particularly, it has been demonstrated that the analysis of the thermal plasma generated during arc or laser welding can supply information about the process and, thus, about the quality of the weld. In some critical applications (e.g. the aerospace sector), an early, real-time detection of defects in the weld seam (oxidation, porosity, lack of penetration, ...) is highly desirable as it can reduce expensive non-destructive testing (NDT). Among others techniques, full spectroscopic analysis of the plasma emission is known to offer rich information about the process itself, but it is also very demanding in terms of real-time implementations. In this paper, we proposed a technique for the analysis of the plasma emission spectrum that is able to detect, in real-time, changes in the process parameters that could lead to the formation of defects in the weld seam. It is based on the estimation of the electronic temperature of the plasma through the analysis of the emission peaks from multiple atomic species. Unlike traditional techniques, which usually involve peak fitting to Voigt functions using the Levenberg-Marquardt recursive method, we employ the LPO (Linear Phase Operator) sub-pixel algorithm to accurately estimate the central wavelength of the peaks (allowing an automatic identification of each atomic species) and cubic-spline interpolation of the noisy data to obtain the intensity and width of the peaks. Experimental tests on TIG-welding using fiber-optic capture of light and a low-cost CCD-based spectrometer, show that some typical defects can be easily detected and identified with this technique, whose typical processing time for multiple peak analysis is less than 20msec. running in a conventional PC.

Mirapeix, Jesús; Cobo, Adolfo; Conde, Olga; Quintela, María Ángeles; López-Higuera, José-Miguel

2005-09-01

223

Economic analysis of HPAI control in the Netherlands II: comparison of control strategies.  

Science.gov (United States)

A combined epidemiological-economic modelling approach was used to analyse strategies for highly pathogenic avian influenza (HPAI) control for the Netherlands. The modelling framework used was InterSpread Plus (ISP), a spatially based, stochastic and dynamic simulation model. A total of eight control strategies were analysed, including pre-emptive depopulation and vaccination strategies. The analysis was carried out for three different regions in the Netherlands: high-, medium- and low-density areas (HDA, MDA and LDA, respectively). The analysis included the veterinary impact (e.g. number of infected premises and duration), but was particularly focused on the impact on direct costs (DC) and direct consequential costs. The efficient set of control strategies for HDA and MDA included strategies based on either pre-emptive depopulation only or combined vaccination and pre-emptive depopulation: D2 (pre-emptive depopulation within a radius of 2 km), RV3 + D1 (ring vaccination within a radius of 3 km and additional pre-emptive depopulation within a radius of 1 km) and PV + D1 (preventive vaccination in non-affected HDAs and pre-emptive depopulation within a radius of 1 km in the affected HDA). Although control solely based on depopulation in most cases showed to be effective for LDA, pre-emptive depopulation showed to have an additional advantage in these areas, that is, prevention of 'virus jumps' to other areas. The pros and cons of the efficient control strategies were discussed, for example, public perception and risk of export restrictions. It was concluded that for the Netherlands control of HPAI preferably should be carried out using strategies including pre-emptive depopulation with or without vaccination. Particularly, the short- and long-term implications on export, that is, indirect consequential costs (ICC) and aftermath costs of these strategies, should be analysed further. PMID:23206287

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

2014-06-01

224

Tobacco control in the Russian Federation- a policy analysis  

Science.gov (United States)

Background The Russian Federation (Russia) has one of the highest smoking rates in the world. The purpose of this study is to analyze past and current trends of the tobacco epidemic in the Russian Federation, review current tobacco control policy responses, and identify areas of opportunity for policy priorities. Methods We used a policy triangle as analytical framework to examine content, context, and processes of Russian tobacco control policy. The analysis was based on secondary data on supply and demand sides of the Russian tobacco epidemic, tobacco-related economic and health effects during Russia’s economic transition, and compliance of Russian tobacco policy with international standards and regulations. Results Tobacco-promoting strategies have specifically targeted women and youth. Russia’s approval of a “National Tobacco Control Concept” and draft for a comprehensive tobacco control bill increasingly align national legislature with the WHO Framework Convention on Tobacco Control (FCTC). However, several structural and cultural factors represent substantial barriers to the policy process. The influence of transnational tobacco companies on policy processes in Russia has so far impeded a full implementation of the FCTC mandates. Conclusions Several strategies have been identified as having the potential to reduce the prevalence of tobacco use in Russia and decrease tobacco-related national health and economic burden: adjusting national tobacco policy by raising tobacco tax from the current lowest level in Europe to at least 70%; consequent enforcement of a complete smoking ban in public places; marketing restrictions; and smoking cessation interventions integrated into primary care. Russia’s tobacco control efforts need to target women and youths specifically to efficiently counter industry efforts. PMID:23339756

2013-01-01

225

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

226

Integrated trajectory and control analysis for generic hypersonic vehicles  

Science.gov (United States)

A tool which supports integrated assessment of air-breathing hypersonic vehicle trajectory management and control strategy has been developed by Hattis and Malchow (1991). Using a two-point boundary value problem solution technique, the tool can construct an entire near-minimum-fuel trajectory and desired control strategy from takeoff to orbit, while satisfying physically derived inequality constraints and while achieving efficient propulsive mode phasing. A strategy is also formulated to construct preliminary trajectory and control history representations with less computational burden than required for the overall flight profile assessment. A tabulated example hypersonic vehicle model has been used to demonstrate the integrated analysis methodology. To assure good numerical behavior when the algorithm uses tabulated model data, a multidimensional cubic spline curve smoothing routine has been developed. A dynamic-pressure-constrained, near-fuel-optimal trajectory was computed to provide examples of information that the methodology can provide. Previously unspecified propulsive discontinuities were located, flight regimes demanding rapid attitude changes were identified, available and closed-loop controller authority was ascertained, and inadequacies in vehicle and specific subsystem model representations were determined.

Hattis, Philip D.; Malchow, Harvey L.; Shaughnessy, John; Chowdhry, Rajiv S.

1991-01-01

227

Controllability Analysis for Operation Margin of Zone 3 Impedance Relay  

Science.gov (United States)

Undesirable operation of zone 3 impedance relay (mho relays) is a possible factor for causing cascading failure as seen in several previous large scale blackouts, where power flow redistribution and power swing caused by outage or switching operations satisfy the condition for the relay operation. So far, the condition itself has not fully been investigated, and therefore, there has been little attempt to avoid the relay operation by means of direct power flow control. This paper analyzes the condition for zone 3 relay operation from the viewpoint of its sensitivity to power flow. An operating margin for security is defined for each relay to carry out effective monitoring. It is newly pointed out that undesirable operation can be effectively avoided by reactive power controls as well as real power controls. The method to compute the operation margin is also given through the analysis of the optimal Var location to control the operation margin. Effectiveness of the proposed method is demonstrated using the IEEE test systems.

Li, Shenghu; Yorino, Naoto; Zoka, Yoshifumi

228

Cost and schedule control systems for safety analysis report projects  

International Nuclear Information System (INIS)

As a part of its waste management program at Savannah River site, Westinghouse Savannah River Company (WSRC) is performing safety analyses and providing safety documentation in support of construction in support of construction and operation of nuclear process facilities. The safety documentation includes a major document, the safety analyses report (SAR), which requires a detailed safety analysis of the facility. It is with the control of cost and schedule of SAR projects that this paper is concerned. The cost and schedule control system (CSCS) models developed for SAR projects comply with the principles and requirements of the US Department of Energy's project management system and criteria. The models apply to the SAR structure and allow calculation of key project performance parameters for the SAR as a whole and for individual chapters and sections. The models are based on the concept of earned value, which represents the periodic, consistent measurement of work performed in terms of the budget assigned to that work

229

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

230

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

231

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

232

Systems Analysis for Material Control and Accountancy Technology (SAMCAT)  

International Nuclear Information System (INIS)

The Systems Analysis for Material Control and Accountancy Technology (SAMCAT) is an interactive computer-based management system developed for the Department of Energy Office of Safeguards and Security, to assist in defining and prioritizing measurement upgrades programs for Material Control and Accountancy (MC ampersand A). The accountancy upgrades options evaluated by SAMCAT in this study are: (1) improvement of the uncertainties in the SNM measurement methods, (2) reduction of throughputs and/or inventories of SNM, and (3) reduction of the material balance accounting period. The goals of the MC ampersand A upgrades program are reduced inventory differences and associated uncertainties, improved detection probabilities for theft/diversion, decreased operating costs, and enhanced material traceability. 6 refs., 3 figs., 2 tabs

233

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

234

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

235

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

236

Control of color imaging systems analysis and design  

CERN Document Server

A Complete One-Stop ResourceWhile digital color is now the technology of choice for printers, the knowledge required to address the quality and productivity issues of these devices is scattered across several technologies, as is its supporting literature. Bringing together information from diverse fields, Control of Color Imaging Systems: Analysis and Design is the first book to provide comprehensive coverage of the fundamentals and algorithms of the numerous disciplines associated with digital color printing in a single resource. The authors review the history of digital printing systems, exp

Mestha, Lalit K

2009-01-01

237

Experimental sensitivity analysis for robustness studies of a controlled system  

International Nuclear Information System (INIS)

Active and adaptive systems consist of various components with different functionalities. As the complexity of the systems increases, reliability and robustness studies become a more complicated task. Sensitivity analysis helps system designers to understand interactions between the system components and to identify the important parameters with significant overall influences on the system performance. To analyze the complex interactions of the components and parameters of an active system with respect to system performance, a framework structure with active vibration damping in a lab scale test rig was set up. With this test rig an experimental sensitivity analysis was performed to investigate the influences of the system components and parameters on the vibration reduction. A higher robustness of the active system was achieved by using adaptive control. (paper)

238

Case-control association analysis of rheumatoid arthritis with candidate genes using related cases  

OpenAIRE

Abstract We performed a case-control association analysis of rheumatoid arthritis (RA) for several candidate genes using the North American Rheumatoid Arthritis Consortium (NARAC) data provided in Genetic Analysis Workshop 15. We conducted the case-control association analysis using all related cases and unrelated controls and compared the results with those from the analysis of samples using only one randomly selected case from each family and all unrelated controls. For both analy...

Yoo Yun; Gao Guimin; Zhang Kui

2007-01-01

239

Multi-Pass Malware Sandbox Analysis with Controlled Internet Connection  

Science.gov (United States)

Malware sandbox analysis, in which a malware sample is actually executed in a testing environment (i.e. sandbox) to observe its behavior, is one of the promising approaches to tackling the emerging threats of exploding malware. As a lot of recent malware actively communicates with remote hosts over the Internet, sandboxes should also support an Internet connection, otherwise important malware behavior may not be observed. In this paper, we propose a multi-pass sandbox analysis with a controlled Internet connection. In the proposed method, we start our analysis with an isolated sandbox and an emulated Internet that consists of a set of dummy servers and hosts that run vulnerable services, called Honeypots in the Sandbox (HitS). All outbound connections from the victim host are closely inspected to see if they could be connected to the real Internet. We iterate the above process until no new behaviors are observed. We implemented the proposed method in a completely automated fashion and evaluated it with malware samples recently captured in the wild. Using a simple containment policy that authorizes only certain application protocols, namely, HTTP, IRC, and DNS, we were able to observe a greater variety of behaviors compared with the completely isolated sandbox. Meanwhile, we confirmed that a noticeable number of IP scans, vulnerability exploitations, and DoS attacks are successfully contained in the sandbox. Additionally, a brief comparison with two existing sandbox analysis systems, Norman Sandbox and CWSandbox, are shown.

Yoshioka, Katsunari; Matsumoto, Tsutomu

240

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  

OpenAIRE

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

241

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)

242

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

243

Mechanism for hydrotalcite decomposition: a controlled rate thermal analysis study.  

Science.gov (United States)

The mechanism for the decomposition of hydrotalcite remains unsolved. Controlled rate thermal analysis enables this decomposition pathway to be explored. Hydrotalcites containing carbonate, vanadate and molybdate were prepared by coprecipitation. The resulting materials were characterised by XRD, simultaneous TG-DTG-DTA and controlled rate thermal analysis (CRTA) to determine the stability and thermal decomposition pathway of the synthesised hydrotalcites. For the carbonate intercalated hydrotalcite dehydration takes place in three steps two of which are quasi-isothermal and one non-isothermal. Dehydroxylation and decarbonation occur separately over the 235-330 and 330-370 degrees C temperature range. A second non-isothermal decarbonation step is observed in the 371-541 degrees C range. In comparison the mixed carbonate-vanadate and carbonate-molybdate hydrotalcites show two dehydration steps and the dehydroxylation and decarbonation occur simultaneously. The observation of three dehydration steps is used to support the model of water molecules in three structurally distinct environments in the hydrotalcite interlayer. CRTA technology provides a mechanism for the decomposition of hydrotalcites. PMID:17991479

Vágvölgyi, Veronika; Palmer, Sara J; Kristóf, János; Frost, Ray L; Horváth, Erzsébet

2008-02-15

244

Bifurcation analysis of a Lyapunov-based controlled boost converter  

Science.gov (United States)

Lyapunov-based controlled boost converters have a unique equilibrium point, which is globally asymptotically stable, for known resistive loads. This article investigates the dynamic behaviors that appear in the system when the nominal load differs from the actual one and no action is taken by the controller to compensate for the mismatch. Exploiting the fact that the closed-loop system is, in fact, planar and quadratic, one may provide not only local but also global stability results: specifically, it is proved that the number of equilibria of the converter may grow up to three and that, in any case, the system trajectories are always bounded, i.e. it is a bounded quadratic system. The possible phase portraits of the closed-loop system are also characterized in terms of the selected bifurcation parameters, namely, the actual load value and the gain of the control law. Accordingly, the analysis allows the numerical illustration of many bifurcation phenomena that appear in bounded quadratic systems through a physical example borrowed from power electronics.

Spinetti-Rivera, Mario; Olm, Josep M.; Biel, Domingo; Fossas, Enric

2013-11-01

245

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; Westerhoff, H. v.

1993-01-01

246

The importance of reference materials in doping-control analysis.  

Science.gov (United States)

Currently a large range of pure substance reference materials are available for calibration of doping-control methods. These materials enable traceability to the International System of Units (SI) for the results generated by World Anti-Doping Agency (WADA)-accredited laboratories. Only a small number of prohibited substances have threshold limits for which quantification is highly important. For these analytes only the highest quality reference materials that are available should be used. Many prohibited substances have no threshold limits and reference materials provide essential identity confirmation. For these reference materials the correct identity is critical and the methods used to assess identity in these cases should be critically evaluated. There is still a lack of certified matrix reference materials to support many aspects of doping analysis. However, in key areas a range of urine matrix materials have been produced for substances with threshold limits, for example 19-norandrosterone and testosterone/epitestosterone (T/E) ratio. These matrix-certified reference materials (CRMs) are an excellent independent means of checking method recovery and bias and will typically be used in method validation and then regularly as quality-control checks. They can be particularly important in the analysis of samples close to threshold limits, in which measurement accuracy becomes critical. Some reference materials for isotope ratio mass spectrometry (IRMS) analysis are available and a matrix material certified for steroid delta values is currently under production. In other new areas, for example the Athlete Biological Passport, peptide hormone testing, designer steroids, and gene doping, reference material needs still need to be thoroughly assessed and prioritised. PMID:21562740

Mackay, Lindsey G; Kazlauskas, Rymantas

2011-08-01

247

Risk Analysis in Robust Control -- Making the Case for Probabilistic Robust Control  

CERN Document Server

This paper offers a critical view of the "worst-case" approach that is the cornerstone of robust control design. It is our contention that a blind acceptance of worst-case scenarios may lead to designs that are actually more dangerous than designs based on probabilistic techniques with a built-in risk factor. The real issue is one of modeling. If one accepts that no mathematical model of uncertainties is perfect then a probabilistic approach can lead to more reliable control even if it cannot guarantee stability for all possible cases. Our presentation is based on case analysis. We first establish that worst-case is not necessarily "all-encompassing." In fact, we show that for some uncertain control problems to have a conventional robust control solution it is necessary to make assumptions that leave out some feasible cases. Once we establish that point, we argue that it is not uncommon for the risk of unaccounted cases in worst-case design to be greater than that of the accepted risk in a probabilistic appro...

Chen, Xinjia; Zhou, Kemin

2007-01-01

248

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

Energy Technology Data Exchange (ETDEWEB)

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 ? 10 nm 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. Highlights: • 3D scaffolds of Mg-carbonate–apatite and anionic-collagen were produced. • The biomimetic approach and the cross-linking with 0.25% GA solution were employed. • The scaffolds showed open-porous structure and apatite crystals on collagen fibrils. • The cross-linked scaffolds exhibited integrity when immersed in culture medium. • SaOs2 cells adhered and proliferated on the cross-linked scaffolds confirming no cytotoxicity.

Sader, Marcia S., E-mail: msader@metalmat.ufrj.br [Prog. Engenharia Metalúrgica e Materiais, COPPE/UFRJ, RJ (Brazil); Martins, Virginia C.A. [Depto. de Química e Física Molecular, IQSC/USP, SP (Brazil); Gomez, Santiago [Dept. Anatomía Patológica, Universidad de Cádiz, Cadiz (Spain); LeGeros, Racquel Z. [Department of Biomaterials and Biomimetics, New York University College of Dentistry, NY (United States); Soares, Gloria A. [Prog. Engenharia Metalúrgica e Materiais, COPPE/UFRJ, RJ (Brazil)

2013-10-15

249

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)

250

Spatial control of groundwater contamination, using principal component analysis  

Science.gov (United States)

A study on the geochemistry of groundwater was carried out in a river basin of Andhra Pradesh to probe into the spatial controlling processes of groundwater contamination, using principal component analysis (PCA). The PCA transforms the chemical variables, pH, EC, Ca2+, Mg2+, Na+, K+, HCO, Cl-, SO, NO and F-, into two orthogonal principal components (PC1 and PC2), accounting for 75% of the total variance of the data matrix. PC1 has high positive loadings of EC, Na+, Cl-, SO, Mg2+ and Ca2+, representing a salinity controlled process of geogenic (mineral dissolution, ion exchange, and evaporation), anthropogenic (agricultural activities and domestic wastewaters), and marine (marine clay) origin. The PC2 loadings are highly positive for HCO , F-, pH and NO, attributing to the alkalinity and pollution controlled processes of geogenic and anthropogenic origins. The PC scores reflect the change of groundwater quality of geogenic origin from upstream to downstream area with an increase in concentration of chemical variables, which is due to anthropogenic and marine origins with varying topography, soil type, depth of water levels, and water usage. Thus, the groundwater quality shows a variation of chemical facies from Na+ > Ca2+ > Mg2+ > K+: HCO > Cl- > SO NO > F-at high topography to Na+ > Mg2+ > Ca2+ > K+: Cl- > HCO > SO NO > F- at low topography. With PCA, an effective tool for the spatial controlling processes of groundwater contamination, a subset of explored wells is indexed for continuous monitoring to optimize the expensive effort.

Rao, N. Subba

2014-06-01

251

Computer Models for IRIS Control System Transient Analysis  

Energy Technology Data Exchange (ETDEWEB)

This report presents results of the Westinghouse work performed under Task 3 of this Financial Assistance Award and it satisfies a Level 2 Milestone for the project. Task 3 of the collaborative effort between ORNL, Brazil and Westinghouse for the International Nuclear Energy Research Initiative entitled “Development of Advanced Instrumentation and Control for an Integrated Primary System Reactor” focuses on developing computer models for transient analysis. This report summarizes the work performed under Task 3 on developing control system models. The present state of the IRIS plant design – such as the lack of a detailed secondary system or I&C system designs – makes finalizing models impossible at this time. However, this did not prevent making considerable progress. Westinghouse has several working models in use to further the IRIS design. We expect to continue modifying the models to incorporate the latest design information until the final IRIS unit becomes operational. Section 1.2 outlines the scope of this report. Section 2 describes the approaches we are using for non-safety transient models. It describes the need for non-safety transient analysis and the model characteristics needed to support those analyses. Section 3 presents the RELAP5 model. This is the highest-fidelity model used for benchmark evaluations. However, it is prohibitively slow for routine evaluations and additional lower-fidelity models have been developed. Section 4 discusses the current Matlab/Simulink model. This is a low-fidelity, high-speed model used to quickly evaluate and compare competing control and protection concepts. Section 5 describes the Modelica models developed by POLIMI and Westinghouse. The object-oriented Modelica language provides convenient mechanisms for developing models at several levels of detail. We have used this to develop a high-fidelity model for detailed analyses and a faster-running simplified model to help speed the I&C development process. Section 6 describes an ACSL model that Westinghouse started but suspended developing for the moment. ACSL is an old simulation language that Westinghouse used on many projects. It may (or may not) offer some advantages during the later stages of detailed plant design and analysis, but supporting the ACSL model does not appear to be necessary at this time. Section 7 summarizes our expectations for future development.

Gary D. Storrick; Bojan Petrovic; Luca Oriani

2007-01-31

252

LSAP-DIGLIB, Linear Control System Design, Analysis, Plotting  

International Nuclear Information System (INIS)

1 - Description of program or function: LSAP (Linear Systems Analysis Program) is an interactive program with graphics capability provided through DIGLIB (Device Independent Graphics Library) that can be used for the analysis and design of linear control systems. Nearly all the classical design tools are available, including manipulation of transfer functions and generation of root locus, time response, and frequency response plots. The program is capable of working with continuous time systems and sampled data systems. For continuous time systems, the Laplace transform is used and for sampled data systems, the Z-transform is used. The capability to convert from a Laplace to a Z-transform is provided. The program is intended primarily for the analysis of feedback control systems. The system configuration or parameters can be changed easily, allowing the user to design compensation networks and perform sensitivity analyses in a very convenient manner. DIGLIB is a collection of general graphics subroutines. It was designed to be small, reasonably fast, device-independent, and compatible with RT-11, RSX-11M, and VMS and readily usable by casual programmers for two-dimensional plotting. DIGLIB has device drivers for Tektronix 4010, 4012, 4014, 4025, and 4027 terminals; VT100 terminals with the retro-graphics option; GIGI terminals, CalComp 1012 plotters, and Lexidata 3400 color graphics systems. 2 - Method of solution: LSAP performs its modeling by defining and operating ms its modeling by defining and operating upon polynomial fraction representations of transfer functions. It is a command oriented program. A command is entered, together with any necessary data, and then executed. The program is then ready for the next command. The MAIN procedure accepts a command and calls the appropriate command procedure, until the program is halted. Each command procedure uses any utilities required for the execution of the command. The commands interact with global data in two basic ways. All defined transfer functions are global records, which exist in a linked list. All commands except HALT and HELP operate upon these records. Also included in global data are switches, flags, pointers, and scalars which describe the state of the program and control the operations performed by the commands. 3 - Restrictions on the complexity of the problem: The program can only be applied to systems which can be described by a collection of rational transfer functions that are either Laplace or Z-transforms. The order of the numerator or denominator polynomials cannot exceed 20

253

Control and inhibition analysis of complex formation processes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Proteolytic degradation of the extracellular matrix (ECM is a key event in tumour metastasis and invasion. Matrix metalloproteinases (MMPs are a family of endopeptidases that degrade most of the components of the ECM. Several broad-spectrum MMP inhibitors (MMPIs have been developed, but have had little success due to side effects. Thus, it is important to develop mathematical methods to provide new drug treatment strategies. Matrix metalloproteinase 2 (MMP2 activation occurs via a mechanism involving complex formation that consists of membrane type 1 MMP (MT1-MMP, tissue inhibitor of matrix metalloproteinase 2 (TIMP2 and MMP2. Here, we focus on developing a method for analysing the complex formation process. Results We used control analysis to investigate inhibitor responses in complex formation processes. The essence of the analysis is to define the response coefficient which measures the inhibitory efficiency, a small fractional change of concentration of a targeting molecule in response to a small fractional change of concentration of an inhibitor. First, by using the response coefficient, we investigated models for general classes of complex formation processes: chain reaction systems composed of ordered steps, and chain reaction systems and site-binding reaction systems composed of unordered multi-branched steps. By analysing the ordered step models, we showed that parameter-independent inequalities between the response coefficients held. For the unordered multi-branched step models, we showed that independence of the response coefficients with respect to equilibrium constants held. As an application of our analysis, we discuss a mathematical model for the MMP2 activation process. By putting the experimentally derived parameter values into the model, we were able to conclude that the TIMP2 and MMP2 interaction is the most efficient interaction to consider in selecting inhibitors. Conclusions Our result identifies a new drug target in the process of the MMP2 activation. Thus, our analysis will provide new insight into the design of more efficient drug strategies for cancer treatment.

Saitou Takashi

2012-08-01

254

Diffusing wave spectroscopy applied to material analysis and process control  

International Nuclear Information System (INIS)

Diffusing Wave Spectroscopy (DWS) was studied as a method of laboratory analysis of sub-micron particles, and developed as a prospective in-line, industrial, process control sensor, capable of near real-time feedback. No sample pre-treatment was required and measurement was via a non-invasive, flexible, dip in probe. DWS relies on the concept of the diffusive migration of light, as opposed to the ballistic scatter model used in conventional dynamic light scattering. The specific requirements of the optoelectronic hardware, data analysis methods and light scattering model were studied experimentally and, where practical, theoretically resulting in a novel technique of analysis of particle suspensions and emulsions of volume fractions between 0.01 and 0.4. Operation at high concentrations made the technique oblivious to dust and contamination. A pure homodyne (autodyne) experimental arrangement described was resilient to environmental disturbances, unlike many other systems which utilise optical fibres or heterodyne operation. Pilot and subsequent prototype development led to a highly accurate method of size ranking, suitable for analysis of a wide range of suspensions and emulsions. The technique was shown to operate on real industrial samples with statistical variance as low as 0.3% with minimal software processing. Whilst the application studied was the analysis of TiO2 suspensions, a diverse range of materials including polystyrene beads, cell pastes and luding polystyrene beads, cell pastes and industrial cutting fluid emulsions were tested. Results suggest that, whilst all sizing should be comparative to suitable standards, concentration effects may be minimised and even completely modelled-out in many applications. Adhesion to the optical probe was initially a significant problem but was minimised after the evaluation and use of suitable non stick coating materials. Unexpected behaviour in the correlation in the region of short decay times led to consideration of the effects of rotational diffusion coefficient. The inherent instability of high density suspensions instigated high speed analysis techniques capable of monitoring suspensions that were undergoing rapid change as well as suggesting novel methods for the evaluation of the state of sample dispersion. (author)

255

Cost-effectiveness analysis in Chagas' disease vectors control interventions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english After a large scale field trial performed in central Brazil envisaging the control of Chagas' disease vectors in an endemic area colonized by Triatoma infestans and T. sordida the cost-effectiveness analysis for each insecticide/formulation was performed. It considered the operational costs and the [...] prices of insecticides and formulations, related to the activity and persistence of each one. The end point was considered to be less than 90% of domicilliary unitis (house + annexes) free of infestation. The results showed good cost-effectiveness for a slow-release emulsifiable suspension (SRES) based on PVA and containing malathion as active ingredient, as well as for the pyrethroids tested in this assay-cyfluthrin, cypermethrin, deltamethrin and permethrin.

A. M., Oliveira Filho.

256

Cost-effectiveness analysis in Chagas' disease vectors control interventions  

Directory of Open Access Journals (Sweden)

Full Text Available After a large scale field trial performed in central Brazil envisaging the control of Chagas' disease vectors in an endemic area colonized by Triatoma infestans and T. sordida the cost-effectiveness analysis for each insecticide/formulation was performed. It considered the operational costs and the prices of insecticides and formulations, related to the activity and persistence of each one. The end point was considered to be less than 90% of domicilliary unitis (house + annexes free of infestation. The results showed good cost-effectiveness for a slow-release emulsifiable suspension (SRES based on PVA and containing malathion as active ingredient, as well as for the pyrethroids tested in this assay-cyfluthrin, cypermethrin, deltamethrin and permethrin.

A. M. Oliveira Filho

1989-01-01

257

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.

258

Model analysis of mechanisms controlling pneumatic soil vapor extraction  

DEFF Research Database (Denmark)

The efficiency of traditional soil venting or soil vapor extraction (SVE) highly depends on the architecture of the subsurface because imposed advective air flow tends to bypass low-permeable contaminated areas. Pneumatic SVE is a technique developed to enhance remediation efficiency of heterogeneous soils by enforcing large fluctuating pressure fronts through the contaminated area. Laboratory experiments have suggested that pneumatic SVE considerably improves the recovery rate from low-permeable units. We have analyzed the experimental results using a numerical code and quantified the physical processes controlling the functioning of the method. A sensitivity analysis for selected boundary conditions, initial conditions and parameters was carried out to examine how the method behaves under conditions different from the experimental set-up. The simulations show that at the laboratory level the pneumatic venting technology is superior to the traditional technique, and that the method is particularly efficient in cases where large permeability contrasts exist between soil units in the subsurface.

HØier, Camilla Kruse; Sonnenborg, Torben Obel

2009-01-01

259

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

260

Gene set control analysis predicts hematopoietic control mechanisms from genome-wide transcription factor binding data.  

Science.gov (United States)

Transcription factors are key regulators of both normal and malignant hematopoiesis. Chromatin immunoprecipitation (ChIP) coupled with high-throughput sequencing (ChIP-Seq) has become the method of choice to interrogate the genome-wide effect of transcription factors. We have collected and integrated 142 publicly available ChIP-Seq datasets for both normal and leukemic murine blood cell types. In addition, we introduce the new bioinformatic tool Gene Set Control Analysis (GSCA). GSCA predicts likely upstream regulators for lists of genes based on statistical significance of binding event enrichment within the gene loci of a user-supplied gene set. We show that GSCA analysis of lineage-restricted gene sets reveals expected and previously unrecognized candidate upstream regulators. Moreover, application of GSCA to leukemic gene sets allowed us to predict the reactivation of blood stem cell control mechanisms as a likely contributor to LMO2 driven leukemia. It also allowed us to clarify the recent debate on the role of Myc in leukemia stem cell transcriptional programs. As a result, GSCA provides a valuable new addition to analyzing gene sets of interest, complementary to Gene Ontology and Gene Set Enrichment analyses. To facilitate access to the wider research community, we have implemented GSCA as a freely accessible web tool (http://bioinformatics.cscr.cam.ac.uk/GSCA/GSCA.html). PMID:23220237

Joshi, Anagha; Hannah, Rebecca; Diamanti, Evangelia; Göttgens, Berthold

2013-04-01

261

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

262

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)

263

Multi-fingerprint and quality control analysis of tea polysaccharides.  

Science.gov (United States)

High performance gel permeation chromatography (HPGPC), ultraviolet-visible spectra (UV), infrared absorption spectra (IR) and ion chromatography (IC) techniques were used in fingerprint analysis of tea polysaccharides (TPS). Multi-fingerprint was applied to assess TPS consistency and to discriminate other polysaccharides in order to achieve the quality control of TPS. The experimental data for spectrogram and chromatogram were used for similarity calculation, included angle cosine method and correlation coefficient method. The results showed that the UV absorption spectra, IR absorption spectra and IC of 22 batches of TPS had a high degree of similarity, respectively, and the similar indexes were up to 0.9985 and 0.9475. Other five polysaccharides were compared with the referential fingerprint, which had an obvious difference. It could conclude that some differences were really existed between TPS and other polysaccharides; and multi-fingerprint is a more useful means to control the quality of TPS than one simple fingerprint. This analytical method is highly rapid, effective, visual and accurate for polysaccharides research. PMID:23218339

Wang, Yuanfeng; Xian, Jianghui; Xi, Xionggang; Wei, Xinlin

2013-01-30

264

Multiple channel coincidence detector and controller for microseismic data analysis  

Energy Technology Data Exchange (ETDEWEB)

A multiple channel coincidence detector circuit is provided for analyzing data either in real time or recorded data on a magnetic tape during an experiment for determining location and progression of fractures in an oil field or the like while water is being injected at high pressure in wells located in the field. The circuit is based upon the utilization of a set of parity generator trees combined with monostable multivibrators to detect the occurrence of two events at any pair of channel input terminals that are within a preselected time frame and have an amplitude above a preselected magnitude. The parity generators perform an exclusive OR function in a timing circuit composed of monostable multivibrators that serve to yield an output when two events are present in the preselected time frame. Any coincidences falling outside this time frame are considered either noise or not otherwise useful in the analysis of the recorded data. Input pulses of absolute magnitude below the low-level threshold setting of a bipolar low-level threshold detector are unwanted and therefore rejected. A control output is provided for a utilization device from a coincidence hold circuit that may be used to halt a tape search unit at the time of coincidence or perform other useful control functions.

Fasching, George E. (Morgantown, WV)

1976-11-16

265

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

266

HPLC-MS technique for radiopharmaceuticals analysis and quality control  

International Nuclear Information System (INIS)

Potentialities of liquid chromatography with mass spectrometric detector (MSD) were investigated with the objective of quality control of radiopharmaceuticals; 2-deoxy-2-[18F]fluoro-D-glucose (FDG) being an example. Screening of suitable MSD analytical lines is presented. Mass-spectrometric monitoring of acetonitrile-aqueous ammonium formate eluant by negatively charged FDG.HCO2- ions enables isotope analysis (specific activity) of the radiopharmaceutical at m/z 227 and 226. Kryptofix 222 provides an intense MSD signal of the positive ion associated with NH4+ at m/z 394. Expired FDG injection samples contain decomposition products from which at least one labelled by 18F and characterised by signal of negative ions at m/z 207 does not correspond to FDG fragments but to C5 decomposition products. A glucose chromatographic peak, characterised by m/z 225 negative ion is accompanied by a tail of a component giving a signal of m/z 227, which can belong to [18O]glucose; isobaric sorbitol signals were excluded but FDG-glucose association occurs in the co-elution of separation of model mixtures. The latter can actually lead to a convoluted chromatographic peak, but the absence of 18F makes this inconsistent. Quantification and validation of the FDG component analysis is under way. (author)

267

Radar tower frequency control and earthquake response analysis  

Science.gov (United States)

For the sake of avoiding the impact of surrounding buildings on the radar, radar tower is usually high, generally up to 100 meters. As the radar performance reasons, the required fundamental frequency of radar tower should not be less than 1Hz. For such a tall building, how to control the frequency of radar tower is an issue worth studying. Through a lot of calculations and analyses, paper reaches a number of laws to increase frequency: 1) Lowering center of gravity of the structure; 2) Setting leaning bracing; 3) Raising the thickness or number of shear walls. In the above structural frequencies adjustment methods, setting leaning bracing and reducing the top mass of the structure are the most obvious effects of all. At the same time, paper also discusses on the seismic response of radar tower. Analyses used for earthquake are response spectrum method, time history analysis method and random vibration analysis. Three methods of calculation results show: radar tower performance meets China's seismic code to regulate specifications of the story drift limits.

Wu, Zeyu; Li, Yuhe; Wang, Fuming; Wang, Dongwei

2010-04-01

268

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)

269

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

270

Analysis of man-machine interaction for control and display system in main control room of light water reactor  

International Nuclear Information System (INIS)

One of potential hazard in Nuclear Power Plant is the failure of its operation. The accident or operation failure in the reactor must be concerned event its probability is low. The important thing should be concerned is 'Analysis of Man-Machine Interaction (MMI) for Control and Display System in Main Control Room (MCR) of Nuclear Power Reactor', especially LWR type. Control and Display System in MCR of Reactor is the main part of MMI link process in Reactor MCR work system. Signal from display system showed performance process in reactor, while this signal will be received by operator. This signal will be described through central nerve for making decision what kind must be done. Then the operator manage the next process of reactor operation through control system. So by knowing Analysis of Man-Machine Interaction for Control and Display System in Main Control Room of Power Reactor, we can understand human error probability of the operator in reactor operation

271

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

272

Analysis of hygienic critical control points in boar semen production.  

Science.gov (United States)

The present study addresses the microbiological results of a quality control audit in artificial insemination (AI) boar studs in Germany and Austria. The raw and processed semen of 344 boars in 24 AI boar studs were analyzed. Bacteria were found in 26% (88 of 344) of the extended ejaculates and 66.7% (18 of 24) of the boar studs. The bacterial species found in the AI dose were not cultured from the respective raw semen in 95.5% (84 of 88) of the positive samples. These data, together with the fact that in most cases all the samples from one stud were contaminated with identical bacteria (species and resistance profile), indicate contamination during processing. Microbiological investigations of the equipment and the laboratory environment during semen processing in 21 AI boar studs revealed nine hygienic critical control points (HCCP), which were addressed after the first audit. On the basis of the analysis of the contamination rates of the ejaculate samples, improvements in the hygiene status were already present in the second audit (P = 0.0343, F-test). Significant differences were observed for heating cabinets (improvement, P = 0.0388) and manual operating elements (improvement, P = 0.0002). The odds ratio of finding contaminated ejaculates in the first and second audit was 1.68 (with the 95% confidence interval ranging from 1.04 to 2.69). Furthermore, an overall good hygienic status was shown for extenders, the inner face of dilution tank lids, dyes, and ultrapure water treatment plants. Among the nine HCCP considered, the most heavily contaminated samples, as assessed by the median scores throughout all the studs, were found in the sinks and/or drains. High numbers (>10(3) colony-forming units/cm(2)) of bacteria were found in the heating cabinets, ejaculate transfer, manual operating elements, and laboratory surfaces. In conclusion, the present study emphasizes the need for both training of the laboratory staff in monitoring HCCP in routine semen production and audits in such AI centers for the external control of hygiene parameters. PMID:25459424

Schulze, M; Ammon, C; Rüdiger, K; Jung, M; Grobbel, M

2015-02-01

273

Analysis of Boost Converter Using PI Control Algorithms  

OpenAIRE

This paper explains about the boost converter and control algorithm to reduce harmonics. For the improvement of the functionality of the boost converter there are many methods available among which I consider PI controller in voltage mode control path. Initially I discussed the basic function of the boost converter. Then I derived the transfer function of the complete system. Then I considered model and simulate into matlab without PI controller. Finally I used PI controller in which the valu...

Mitulkumar R Dave, K. C. Dave

2012-01-01

274

Model-based analysis of control performance in sewer systems  

DEFF Research Database (Denmark)

Design and assessment of control in wastewater systems has to be tackled at all levels, including supervisory and regulatory level. We present here an integrated approach to assessment of control in sewer systems based on modelling and the use of process control tools to assess the controllability of the process. A case study of a subcatchment area in Copenhagen (Denmark) is used to illustrate the combined approach in modelling of the system and control assessment.

Mollerup, Ane HØyer; Mauricio Iglesias, Miguel

2012-01-01

275

Odd-harmonic repetitive control of an active filter under varying network frequency: control design and stability analysis  

OpenAIRE

This work deals with the design and analysis of a controller for a shunt active power filter. The design is based on combined feedforward and feedback actions, the last using repetitive control, and aims at the obtention of a good closedloop performance in spite of the possible frequency variations that may occur in the electrical network. As these changes affect the performance of the controller, the proposal includes a compensation technique consisting of an adaptive ch...

Olm Miras, Josep Maria; Ramos Fuentes, Germa?n Andre?s; Costa Castello?, Ramon; Cardoner Parpal, Rafel

2010-01-01

276

Simulation of the treat-upgrade automatic reactor control system  

International Nuclear Information System (INIS)

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 measureraulic 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

277

THE ANALYSIS, SIMULATION, AND IMPLEMENTATION OF CONTROL STRATEGIES FOR A PULSEWIDTH MODULATED INDUCTION MOTOR DRIVE  

OpenAIRE

The purpose of this research is to analyze, simulate, and compare two different control strategies for a variable speed pulsewidth modulated induction motor drive, and implement one of the control strategies using the Motorola MC68F333 inicrocontroller. The two strategies examined in this technical report are volts per hertz control and field oriented control. The benefits and limitations of each strategy are examined through theoretical analysis. Verification of the analysis is performed by ...

Roller, Scott D.; Ong, Chee Mun

1996-01-01

278

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)

279

Zonal frequency analysis of the gyral and sulcal extent of cerebral infarcts. Part III: Middle cerebral artery and watershed infarcts  

International Nuclear Information System (INIS)

We tested the hypothesis that frequency analysis of the anatomic zones affected by single anterior (A), posterior (P), and middle (M) cerebral artery (CA), multivessel, and watershed infarcts will disclose specific sites (peak zones) most frequently involved by each type, sites most frequently injured by multiple different types (vulnerable zones), and overlapping sites of equal relative frequency for two or more different types of infarct (equal frequency zones). We adopted precise definitions of each vascular territory. CT and MRI studies of 50 MCA, 20 ACA-MCA, three PCA-MCA, and 30 parasagittal watershed infarcts were mapped onto a standard template. Relative infarct frequencies in each zone were analyzed within and across infarct types to identify the centers and peripheries of each, vulnerable zones, and equal frequency zones. These data were then correlated with the prior analysis of 47 ACA, PCA, dual ACA-PCA, and ACA-PCA-MCA infarcts. Zonal frequency data for MCA and watershed infarcts, the sites of peak infarct frequency, the sites of vulnerability to diverse infarcts, and the overlapping sites of equal infarct frequency are tabulated and displayed in standardized format for direct comparison of different infarcts. This method successfully displays the nature, sites, and extent of individual infarct types, illustrates the shifts in zonal frequency and lesion center that attend dual and triple infarcts, and clarifies the relationships among the diverse types ofe relationships among the diverse types of infarct. (orig.)

280

Analysis of Hydrogen Control Strategy Using Igniter during Severe Accident  

International Nuclear Information System (INIS)

The Severe Accident Management Guidelines (SAMGs) for the operating pressurized water reactor (PWR) have been completed within 2006. Among the SAMG strategies, mitigation-07 is the most important strategy for managing a severe accident of a PWR in order to reduce containment hydrogen. The fastest way to reduce the containment hydrogen concentration is to intentionally ignite the hydrogen. For this strategy, igniters exist in Optimized Power Reactor 1000 (OPR 1000) to burn hydrogen for a severe accident. For using the igniters during a severe accident, the adverse effects such as the explosion of the hydrogen mixture should be considered for containment integrity. However, an applicable discrimination method to activate the igniters does not exist, so that the hydrogen control strategy using the igniters cannot be chosen during a severe accident. Thus, this study focused on suggesting an applicable discrimination method to carry out the strategy of using the igniters. In this study, the specific plant used for this analysis is Ulchin Unit 5 and 6, OPR 1000 plant, in Korea

281

Supervised hierarchical bayesian model-based electomyographic control and analysis.  

Science.gov (United States)

This work suggests a supervised hierarchical Bayesian model for surface electromyography (sEMG)-based motion classification and its strategy analysis. The proposed model unifies the optimal feature extraction and classification through probabilistic inference and learning by identifying the latent neural states (LNSs) that govern a collection of sEMG signals. In addition, the inference step provides an approach to identify distinct muscle activation strategies according to sEMG patterns based on LNSs. To validate the model, nine-class classification using four sEMG sensors on the limb motions is tested. The model performance is evaluated with relatively high and low activation levels, generalized classification across subjects and online classification. The model, based on LNSs to capture various motions, is assessed with respect to activation levels, individual subjects and transition during online classification. Our approach cannot only classify sEMG patterns, but also provide the interpretation of sEMG strategic patterns. This work supports the potential of the proposed model for sEMG control-based applications. PMID:24108752

Han, Hyonyoung; Jo, Sungho

2014-07-01

282

Microcomputer controlled chemical and radiochemical separations and analysis  

International Nuclear Information System (INIS)

An automated radiochemical flow analysis (ARFA) system was developed which integrates chemical and radiochemical techniques into one system through the use of a microcomputer. The operator, through the microcomputer, controls valves and pumps to transfer sample and reagent solutions to counting loops, ion exchange columns and holdup reservoirs. A Ge(Li) detector monitors the radioactivity of samples delivered to counting loops or of species retained on ion exchange resins. Trace metals present in tap and river water samples were concentrated on Chelex-100 ion exchange resin, stripped with acid, activated and counted. Zn, Cu, Mn, Br and K were determined at ng/mL concentrations and Dy, Eu, and U were determiend at sub ng/mL concentrations. Species in reactor coolant water at the OSU TRIGA reactor were concentrated and counted directly on an ion exchange column. Test solutions of Mn2+, Eu3+, In3+, Dy3+ tracers and humic acid were passed through a Chelex-100 resin. The retention behavior of the metal tracers was used to follow the kinetics of the metal complexation

283

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

284

Analysis of water level control methods for nuclear steam generator  

International Nuclear Information System (INIS)

Nuclear steam generator (SG) is a highly complex nonlinear time-changed system. The inverse dynamics effects, which are caused by shrink and swell under transient, startup and lower power operation, make the water level difficult to control. Methods of SG water level control are analyzed. The shortcoming of conventional PI(D) control for SG level is pointed out. It emphatically expounds the fuzzy logic control and the neural network control to nuclear steam generator level. Finally, the author brings forward his opinion upon the advance tendency of SG water level control. (authors)

285

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

286

Task analysis of soft control operations in advanced main control rooms  

International Nuclear Information System (INIS)

In advanced main control rooms (MCRs), operations are performed using soft controls such as mo uses, touch panels and so on. The soft control operations require totally different operation process from that of conventional controls. Especially, the interface management tasks are most distinguishable characteristics of soft controls. In this work, simulation data of an advanced MCR was analyzed in order to observe operators' behavior during soft control operations

287

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

OpenAIRE

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 ...

Nagasekhar Reddy, P.

2013-01-01

288

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.

289

Output controllability analysis of fixed speed wind turbine  

OpenAIRE

This paper deals with the concepts of output controllability and steady output controllability, it demonstrates that they are not equivalent of concepts. A linear system has been calculated from the nonlinear equations of the squirrel cage induction generator, supposing it connected directly to the grid and assuming a steady state operating point. The study of output controllability and steady-output controllability concepts of the introduced system is done.

Domi?nguez Garci?a, Jose? Lui?s; Garci?a Planas, Mari?a Isabel

2011-01-01

290

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; Poulsen, J K

2003-01-01

291

Performance Analysis of Ship Tracking using PID/Fuzzy Controller  

OpenAIRE

Accurate ship Path following is an issue of the Marine Navigation Technology. In order to achieve accurate path following in ship navigation various controllers like PID(Proportional-Integral-Derivative), Adaptive and Predictive controllers are used. However, the main problem of ships is the PID controller is that they are set to work under specific conditions. Even though predictive controllers have predictive capability and are giving accurate results but they are computationally complex. I...

Sanjay N, Adinath Jain

2013-01-01

292

Formal Design and Analysis of a Wastewater Treatment Control System based on Petrinet  

OpenAIRE

This paper proposes a new control design approach for industrial wastewater treatment where its logic control is verifiable. In this research, a treatment control design in a lab-scale was controlled by a microcontroller circuit. The developed system combined anaerobic digestion, aeration and filtration process. Its logic control algorithm was designed by using Signal Interpreted Petri Net. In the logic verification, six analysis properties were satisfied: conflict free (logical process had n...

Panjaitan, Seno D.; Berlian Sitorus

2012-01-01

293

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

OpenAIRE

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

294

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

295

A theoretical analysis of optimum consumer population and its control.  

Science.gov (United States)

Material production is related to population consumption in every society. Consumption also constantly transforms materials, energy, and information. In this sense, consumption provides both impetus for material production and a self-adapting mechanism for population development and control. Population structure variables affecting economic production can be divided according to non-adults, working-age work force and the elderly, social status, and urban-rural structure. The consumptive structures among people of different social status reflect different needs for social and economic development. The theoretical calculation of the consumer population in the national economy demonstrates that the national income in a certain year of a given national economy equals consumption fund plus accumulation fund where consumption fund includes social consumption fund and residential consumption fund. Social consumption fund is spent mostly on public utilities, administrative management, national defense, education, public health and urban construction, as well as on environment management and disaster relief. The residential consumption fund can be divided into basic expenditure such as clothing, food, shelter and transportation, and self-improvement expenditure such as recreation, education, and travel. As a result of economic development, not only the percentage of the expenditure on food will decrease and the percentage of the expenditure on clothing, shelter, transportation, and other daily necessities will increase, but expenses on recreation and education also will grow. Residential consumption is divided into subsistence consumption (Type I consumption) and self-improvement (recreation and education) consumption (Type II consumption) in order to determine consumer population and the degree of urbanization and its impact upon social and economic development. A moderate consumer population model of urban and rural areas was established by using the urban and rural consumption structure elasticity. This model was used in the correlation analysis of the coordinated healthy development of optimum consumer population and the economy. PMID:12288173

Jiang, Z; Mao, Z; Wang, H

1994-01-01

296

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. PMID:24753575

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

2014-05-13

297

Design, analysis and presentation of factorial randomised controlled trials  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The evaluation of more than one intervention in the same randomised controlled trial can be achieved using a parallel group design. However this requires increased sample size and can be inefficient, especially if there is also interest in considering combinations of the interventions. An alternative may be a factorial trial, where for two interventions participants are allocated to receive neither intervention, one or the other, or both. Factorial trials require special considerations, however, particularly at the design and analysis stages. Discussion Using a 2 × 2 factorial trial as an example, we present a number of issues that should be considered when planning a factorial trial. The main design issue is that of sample size. Factorial trials are most often powered to detect the main effects of interventions, since adequate power to detect plausible interactions requires greatly increased sample sizes. The main analytical issues relate to the investigation of main effects and the interaction between the interventions in appropriate regression models. Presentation of results should reflect the analytical strategy with an emphasis on the principal research questions. We also give an example of how baseline and follow-up data should be presented. Lastly, we discuss the implications of the design, analytical and presentational issues covered. Summary Difficulties in interpreting the results of factorial trials if an influential interaction is observed is the cost of the potential for efficient, simultaneous consideration of two or more interventions. Factorial trials can in principle be designed to have adequate power to detect realistic interactions, and in any case they are the only design that allows such effects to be investigated.

Little Paul

2003-11-01

298

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

299

Quality control analysis of imported fertilizers used in Ghana  

International Nuclear Information System (INIS)

Twenty three (23) imported fertilizer samples of 5 fertilizer types have been analysed to determine their quality. The main objective of this research was to validate specifications indicated by manufacturers' on their fertilizer products. To achieve this objective, the fertilizer samples were analysed using five analytical techniques (INAA, AAS, flame photometer, kjeldahl method and UV-visible spectroscopy) to determine the concentrations of macronutrients (N, P, K, Mg, Ca and S), micronutrients (Cu, Na, Fe, Mn, Mo and Zn) and heavy metals (As, Cd, Co, Hg and Pd) in the fertilizer samples. Results obtained from analysis were compared with certified values obtained from the companies and with standard values obtained from MOFA to establish whether the imported fertilizers met standards. Two reference materials (IAEA Soil-7 and SRM 1646a Estuarine Sediment) were used to validate the quantitative methods employed in the INAA and AAS techniques. Good agreements (98%) were obtained between the measured and verified concentrations for most of the elements. Analytical results revealed that the concentrations of the primary macronutrients (N, P and K) claimed by the manufacturers were valid. In contrast, manufacturers' claims for micronutrient concentrations did not agree with analytical results. The concentrations recorded were far below the minimum plant nutrient guarantees. For instance, the highest values recorded for Cu and Zn were 0.0265% and 0.00305% respectively, whiere 0.0265% and 0.00305% respectively, whiles the minimum guaranteed values were set at 0.05%. Heavy metal levels recorded in the fertilizers were insignificant and therefore do not present possible contamination problems during fertilizer application. In conclusion, not all the nutrient requirements expected of imported fertilizers were met. There is therefore the need for a good quality control system to monitor the chemical compositions of fertilizers imported into Ghana (au).

300

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

301

Integrated intelligent control of flexible structures: analysis and experiments  

Science.gov (United States)

This study investigates the feasibility of using distributed force actuators (in addition to hub- torque) to control the tip deflection of a flexible beam-like structure during a rapid reorientation maneuver. The major objectives of the study are to assess system performance and actuator force requirements. Three feedback control schemes are compared to an open- loop control law corresponding to the rigid-body minimum-time solution. These control schemes use (1) a rate feedback hybrid controller, (2) an LQR-type hybrid controller, and (3) an LQR-type integrated controller. Comparisons between these controllers are made on the basis of actuator force required, increase in closed-loop system damping, and time required to execute a 90 degree reorientation maneuver. It was found that the rate-feedback hybrid control scheme results in high damping, but requires large peak-value forces from the actuators. The LQR-type hybrid control scheme requires lower peak-value forces from the actuators, but yields lower damping. The LQR-type integrated control scheme requires even lower actuator forces and a tip deflection that is significant only at the beginning of the maneuver, but results in an increase in the maneuver time.

Bilimoria, Karl D.; Garrett, Frederick E.; Livneh, Rafael; Schmidt, David K.

1993-09-01

302

A Goal-Function Approach to Analysis of Control Situations  

DEFF Research Database (Denmark)

The concept of situations plays a central role in all theories of meaning and context. and serve to frame or group events and other occurrences into coherent meaningful wholes. Situations are typed, may be interconnected and organized into higher level structures. In operation of industrial processes situations should identify operational aspects relevant for control agent’s decision making in plant supervision and control. Control situations can be understood as recurrent and interconnected patterns of control with important implications for control and HMI design. Goal-Function approaches to systems modeling like Multilevel Flow Modeling can be used to represent control situations. The paper will describe an action theoretical foundation for MFM and its use for the development of a theory of control situations.

Lind, Morten

2010-01-01

303

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

304

Application of Multivariable Statistical Techniques in Plant-wide WWTP Control Strategies Analysis  

DEFF Research Database (Denmark)

The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation of the complex multicriteria data sets and allows an improved use of information for effective evaluation of control strategies.

Flores Alsina, Xavier; Comas, J.

2007-01-01

305

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

International Nuclear Information System (INIS)

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 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.)

306

Comprehensive Analysis of the Control Strategy for Hybrid Active Power Filter with Injection Circuit  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes an overview of the analysis of control strategies for Hybrid Active Power Filter with Injection Circuit (IHAPF. This analysis will be the basis of researches of the IHAPF in the future. Simulation results have shown the effectiveness of the control strategies.

MinhThuyen Chau, VanBao Chau

2013-07-01

307

Systems analysis of information sources, their categorization, and communication needs in unit control room  

International Nuclear Information System (INIS)

An analysis was made of information sources and flows in selected function assemblies of the primary coolant circuit of the 440 WWER power plant. The information sources were categorized depending on their importance for unit operation control. The tabulated results of the analysis show the requirements for the control computer and its computing system. (Ha)

308

MODELLING, SIMULATION AND ROBUST ANALYSIS OF THE TEMPERATURE PROCESS CONTROL  

Directory of Open Access Journals (Sweden)

Full Text Available Processes characterized by large time constant, such as those with temperature control systems, are found in a large number of industrial applications. To control such systems, the appropriate mathematical models identification is needed, considering the uncertainties modeling, handling in dynamic operating regime and proposing control solutions. The paper presents a control system used in a part of a complex plant where is needed to maintain temperature at a set point. The controlled installation consists from two connected tanks, for which a simplified mathematical model based on transfer functions are determined, considering additive uncertainties and classical cascade PI control structures are proposed. Developed models and solutions are analyzed by simulation in Matlab environment.

Mircea Dulau

2012-11-01

309

Analysis and control of transitional shear flows using global modes  

OpenAIRE

In this thesis direct numerical simulations are used to investigate two phenomenain shear flows: laminar-turbulent transition over a flat plate and periodicvortex shedding induced by a jet in cross flow. The emphasis is on understanding and controlling the flow dynamics using tools from dynamical systems and control theory. In particular, the global behavior of complex flows is describedand low-dimensional models suitable for control design are developed; this isdone by decomposing the flow i...

Bagheri, Shervin

2010-01-01

310

Analysis and design of controllers for a double inverted pendulum  

OpenAIRE

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

311

Data management and analysis of HLS control system  

International Nuclear Information System (INIS)

The control system of HLS (Hefei Light Source) is based on EPICS. The control data is held in a distributed database, which resides in several IOCs. An EPICS tool, AR, is used to archive the control data. A data management system is developed to manage the archived data. A number of CGI programs make it easy to access the data via WWW, and the programs also provide several functions for analyzing the data. The results can be displayed in various modes

312

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; Poulsen, Jesper Kildegaard

2005-01-01

313

Stability analysis of multiple-robot control systems  

Science.gov (United States)

In a space telerobotic service scenario, cooperative motion and force control of multiple robot arms are of fundamental importance. Three paradigms to study this problem are proposed. They are distinguished by the set of variables used for control design. They are joint torques, arm tip force vectors, and an accelerated generalized coordinate set. Control issues related to each case are discussed. The latter two choices require complete model information, which presents practical modeling, computational, and robustness problems. Therefore, focus is on the joint torque control case to develop relatively model independent motion and internal force control laws. The rigid body assumption allows the motion and force control problems to be independently addressed. By using an energy motivated Lyapunov function, a simple proportional derivative plus gravity compensation type of motion control law is always shown to be stabilizing. The asymptotic convergence of the tracing error to zero requires the use of a generalized coordinate with the contact constraints taken into account. If a non-generalized coordinate is used, only convergence to a steady state manifold can be concluded. For the force control, both feedforward and feedback schemes are analyzed. The feedback control, if proper care has been taken, exhibits better robustness and transient performance.

Wen, John T.; Kreutz, Kenneth

1989-01-01

314

Reliability analysis of digital instrumentation and control systems  

International Nuclear Information System (INIS)

The NUREG-CR/6942 technical report proposed a Markov state transition model for the main feedwater valve (MFV) controller system as part of a Probabilistic Risk Assessment (PRA) of Digital Feedwater Control System (DFWCS). The proposed model extends the Markov model to allow the use of non-exponential distribution in the time to next output of the controller system responsible for maintaining the water level. This case study demonstrates the general application of semi-Markov process model for digital instrumentation and control systems. System failure probability and mission reliability measures are determined. (author)

315

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

316

El control de convencionalidad: análisis en derecho comparado / The control of conventionality: analysis in comparative law  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Spanish Abstract in spanish En el caso Almonacid (2006), por primera vez, la Corte Interamericana de Derechos Humanos enunció la doctrina del control de convencionalidad. El control de convencionalidad ha generado un gran debate académico, especialmente en la doctrina constitucional latinoamericana. Una pregunta que surge en e [...] ste escenario es cuál es la relación entre el control de constitucionalidad y el control de convencionalidad. El derecho comparado nos permitirá aportar argumentos y criterios para abordar esta cuestión. Abstract in english In the Almonacid case (2006), the Inter-American Court of Human Rights enounced for the first time the doctrine of the control of conventionality. The control of conventionality has propelled a significant academic debate, especially between Latin-American constitutional scholars. One question that [...] arises in this scenario is about the relationship between the control of constitutionality and the control of conventionality. The comparative law brings arguments and criteria to address this question.

Gonzalo, Aguilar Cavallo.

2013-12-01

317

Ego Depletion and the Strength Model of Self-Control: A Meta-Analysis  

Science.gov (United States)

According to the strength model, self-control is a finite resource that determines capacity for effortful control over dominant responses and, once expended, leads to impaired self-control task performance, known as "ego depletion". A meta-analysis of 83 studies tested the effect of ego depletion on task performance and related outcomes,…

Hagger, Martin S.; Wood, Chantelle; Stiff, Chris; Chatzisarantis, Nikos L. D.

2010-01-01

318

Control-Flow Analysis of Function Calls and Returns by Abstract Interpretation  

DEFF Research Database (Denmark)

We derive a control-flow analysis that approximates the interprocedural control-flow of both function calls and returns in the presence of first-class functions and tail-call optimization. In addition to an abstract environment, our analysis computes for each expression an abstract control stack, effectively approximating where function calls return across optimized tail calls. The analysis is systematically calculated by abstract interpretation of the stack-based CaEK abstract machine of Flanagan et al. using a series of Galois connections. Abstract interpretation provides a unifying setting in which we 1) prove the analysis equivalent to the composition of a continuation-passing style (CPS) transformation followed by an abstract interpretation of a stack-less CPS machine, and 2) extract an equivalent constraint-based analysis formulation, thereby providing a rational reconstruction of a constraint-based control-flow analysis from abstract interpretation principles.

Midtgaard, Jan; Jensen, Thomas P.

2009-01-01

319

Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System  

OpenAIRE

This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for con...

Jing-Nang Lee; Tsung-Min Lin; Chien-Chih Chen

2014-01-01

320

Analysis of Access Control Policies in Operating Systems  

Science.gov (United States)

Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

Chen, Hong

2009-01-01

321

Performance Analysis of Ship Tracking using PID/Fuzzy Controller  

Directory of Open Access Journals (Sweden)

Full Text Available Accurate ship Path following is an issue of the Marine Navigation Technology. In order to achieve accurate path following in ship navigation various controllers like PID(Proportional-Integral-Derivative, Adaptive and Predictive controllers are used. However, the main problem of ships is the PID controller is that they are set to work under specific conditions. Even though predictive controllers have predictive capability and are giving accurate results but they are computationally complex. In this work an attempt is made to evaluate the performance of Adaptive (Fuzzy logic and PID controllers in terms of tracking efficiency and computational time. Computational result evaluated using mat lab shows that Adaptive (Fuzzy logic provides better tracking performance than PID.

Sanjay.N1 , Adinath Jain2 , Dr.S.A.Hariprasad

2013-06-01

322

Analysis and Control of a New Chaotic System  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a new three-dimensional autonomous chaotic system is presented. There are three control parameters and three different nonlinear terms in the governed equations. Through the calculation we obtain five equilibrium points. Then fix parameters, we obtain three real equilibrium points,According to the eigenvalues of Jacobian matrix,we know that s1 is a saddle point and s2 ?s3 are saddle-focus points. Then Lyapunov exponents, Lyapunov dimension, Bifurcation diagram and Poincare map are shown through matlab software. And then three different methods, the dislocated feedback control method, the enhancing feedback control method and the speed feedback control method, are used to control the new chaotic system. On the basis of the Routh-Hurwitz theorem , the conditions of stabilization are discussed, and they are also proved theoretically. Numerical simulations show the effectiveness of the three different methods.

ZHANG Xue-bing

2012-03-01

323

Air-breathing hypersonic vehicle guidance and control studies: An integrated trajectory/control analysis methodology, phase 2  

Science.gov (United States)

An integrated trajectory/control analysis algorithm has been used to generate trajectories and desired control strategies for two different hypersonic air-breathing vehicle models and orbit targets. Both models used cubic spline curve fit tabulated winged-cone accelerator vehicle representations. Near-fuel-optimal, horizontal takeoff trajectories, imposing a dynamic pressure limit of 1000 psf, were developed. The first model analysis case involved a polar orbit and included the dynamic effects of using elevons to maintain longitudinal trim. Analysis results indicated problems with the adequacy of the propulsion model and highlighted dynamic pressure/altitude instabilities when using vehicle angle of attack as a control variable. Also, the magnitude of computed elevon deflections to maintain trim suggested a need for alternative pitch moment management strategies. The second analysis case was reformulated to use vehicle pitch attitude relative to the local vertical as the control variable. A new, more realistic, air-breathing propulsion model was incorporated. Pitch trim calculations were dropped and an equatorial orbit was specified. Changes in flight characteristics due to the new propulsion model have been identified. Flight regimes demanding rapid attitude changes have been noted. Also, some issues that would affect design of closed-loop controllers were ascertained.

Hattis, Philip D.; Malchow, Harvey L.

1992-01-01

324

Intelligent control of HVAC systems. Part II: perceptron performance analysis  

OpenAIRE

This is the second part of a paper on intelligent type control of Heating, Ventilating, and Air-Conditioning (HVAC) systems. The whole study proposes a unified approach in the design of intelligent control for such systems, to ensure high energy efficiency and air quality improving. In the first part of the study it is considered as benchmark system a single thermal space HVAC system, for which it is assigned a mathematical model of the controlled system and a mathematical model(algorithm) of...

Ursu, Ioan; Nastase, Ilinca; Caluianu, Sorin; Iftene, Andreea; Tecuceanu, George; Toader, Adrian

2013-01-01

325

Instrumentation of Java program code for control flow analysis  

OpenAIRE

In this thesis we describe an approach and introduce a new tool, called JDeTEx, to extract decision tables from Java programs in order to give the maintenance engineer a better understanding of the control flow of the program. Decision tables are a compact, yet precise way to model the control flow of computer programs. In order to extract the decision tables the explicit and implicit control flow of Java programs needs to be analyzed by the tool. Firstly, the tool uses static byte code analy...

Lo?sch, Felix

2005-01-01

326

Control, stability analysis and grid integration of wind turbines.  

OpenAIRE

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

2008-01-01

327

Analysis of an automatic bunker loading control system  

Energy Technology Data Exchange (ETDEWEB)

Derives a simple formula for the probability of loading for any bunker in an automatically controlled bunker-loading system. The control system wherin each plow is connected to a single level gauge is intended for loading raw coal into bunkers. The sequence of manipulations involved employing queuing theory and matrix calculus techniques is shown. The result obtained allows designers to calculate main characteristics of an automatically controlled loading system for any bulk material without the use of time-consuming computer calculations. 2 refs.

Feofilov, G.P.; Raevskii, S.A.; Voronova, S.V. (Ural' skii VTI (Russian Federation))

1992-07-01

328

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

329

Jitterbug and TrueTime: Analysis Tools for Real-Time Control Systems  

OpenAIRE

The paper presents two recently developed, Matlab-based analysis tools for realtime control systems. The first tool, called Jitterbug, is used to compute a performance criterion for a control loop under various timing conditions. The tool makes it easy to quickly judge how sensitive a controller is to implementation effects such as slow sampling, delays, jitter, etc. The second tool, called TrueTime, allows detailed co-simulation of process dynamics, control task execution, and network commun...

Cervin, Anton; Henriksson, Dan; Lincoln, Bo; A?rze?n, Karl-erik

2002-01-01

330

Analysis of routine communication in the air traffic control system  

Science.gov (United States)

The present project has three related goals. The first is to describe the organization of routine controller-pilot communication. This includes identifying the basic units of communication and how they are organized into discourse, how controllers and pilots use language to achieve their goals, and what topics they discuss. The second goal is to identify the type and frequency of problems that interrupt routine information transfer and prompt pilots and controllers to focus on the communication itself. The authors analyze the costs of these problems in terms of communication efficiency, and the techniques used to resolve these problems. Third, the authors hope to identify factors associated with communication problems, such as deviations from conventional air traffic control procedures.

Clark, Herbert H.; Morrow, Daniel; Rodvoid, Michelle

1990-01-01

331

Hardware based Analysis and Process Control for Laser Brazing Applications  

Science.gov (United States)

Laser brazing is widely used for joining metal sheets in industrial applications, in particular in the automotive sector, where the requirements on surface quality are extremely high. Therefore, quality control and process observation cannot be omitted. This paper presents the current works of a camera based process control system. Hardware-based algorithms for estimation of machine parameters during the process are implemented on FPGA technology. In particular the process velocity is measured in real time which makes the system suitable for controlling tasks to react instantaneously on changes of the velocity.First experimental results on a controlled laser brazing process are presented. Additionally an evaluation of the accuracy of the hardware-based velocity measurement is given.

Ungers, M.; Rolser, R.; Abels, P.

332

Representational Similarity Analysis Reveals Heterogeneous Networks Supporting Speech Motor Control  

DEFF Research Database (Denmark)

The everyday act of speaking involves the complex processes of speech motor control. One important feature of such control is regulation of articulation when auditory concomitants of speech do not correspond to the intended motor gesture. While theoretical accounts of speech monitoring posit multiple functional components required for detection of errors in speech planning (e.g., Levelt, 1983), neuroimaging studies generally indicate either single brain regions sensitive to speech production errors, or small, discrete networks. Here we demonstrate that the complex system controlling speech is supported by a complex neural network that is involved in linguistic, motoric and sensory processing. With the aid of novel real-time acoustic analyses and representational similarity analyses of fMRI signals, our data show functionally differentiated networks underlying auditory feedback control of speech.

Zheng, Zane; Cusack, Rhodri

333

Analysis of Model Predictive Current Control for Voltage Source Inverter  

Directory of Open Access Journals (Sweden)

Full Text Available Model predictive control has become a promising control technology in power converter, because of the good dynamic response and accurate current tracking capability. This study mainly analyzes and verifies the Model Predictive Current control (MPC of a three-phase voltage sources converter. The MPC controller predicts the behavior of the converter for each possible voltage vector on each sampling interval. And a cost function is used to evaluate the voltage vector for the next sampling interval based the predicted load behavior. According to the assessment, an optimal voltage vector is selected and the corresponding switching state is applied to the converter during the next sampling interval. Finally, simulation and experimental results are demonstrated to validate the steady-state and dynamic performance of the proposed system.

Jingang Han

2013-09-01

334

Energy Analysis for Air Conditioning System Using Fuzzy Logic Control  

OpenAIRE

Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC). FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a therma...

Henry Nasution; Hishamuddin Jamaluddin; Jamaluddin Mohd. Syeriff

2011-01-01

335

Toward an explicit analysis of generalization: A stimulus control interpretation  

OpenAIRE

Producing generality of treatment effects to new settings has been a critical concern for applied behavior analysts, but a systematic and reliable means of producing generality has yet to be provided. We argue that the principles of stimulus control and reinforcement underlie the production of most generalized effects; therefore, we suggest interpreting generalization programming in terms of stimulus control. The generalization programming procedures identified by Stokes and Baer (1977) are d...

Kirby, Kimberly C.; Bickel, Warren K.

1988-01-01

336

L? analysis and state-feedback control of Hopfield networks.  

Science.gov (United States)

A nonsymmetric version of Hopfield networks subject to bounded disturbances is considered. Such networks arise in the context of visuo-motor control loops and may, therefore, be used to mimic their complex behavior. In this brief, we adopt the Lur'e-Postnikov systems approach to analyze the induced L? gain of generalized Hopfield networks. A state-feedback control is then designed to accomplish the L?-type performance for Hopfield networks. The results are illustrated through numerical examples. PMID:24808588

Stoica, Adriannmihail; Yaesh, Isaac

2013-09-01

337

Analysis and control on road transportation of nuclear power equipment  

International Nuclear Information System (INIS)

Road transportation of nuclear power equipment is an important link between after-manufacture and before-installation, and it is an essential stage that the manufacture value transfers to the installation and operation value. Taking the transportation of pressurizer for Unit 3 as an example, the article analyses an assortment of potential risks during transportation and puts forward measures to control such risks, in the hope of improving the quality control of transportation. (authors)

338

Extracting Chaos Control Parameters from Time Series Analysis  

Energy Technology Data Exchange (ETDEWEB)

We present a simple method to analyze time series, and estimate the parameters needed to control chaos in dynamical systems. Application of the method to a system described by the logistic map is also shown. Analyzing only two 100-point time series, we achieved results within 2% of the analytical ones. With these estimates, we show that OGY control method successfully stabilized a period-1 unstable periodic orbit embedded in the chaotic attractor.

Santos, R B B [Centro Universitario da FEI, Avenida Humberto de Alencar Castelo Branco 3972, 09850-901, Sao Bernardo do Campo, SP (Brazil); Graves, J C, E-mail: rsantos@fei.edu.br [Instituto Tecnologico de Aeronautica, Praca Marechal Eduardo Gomes 50, 12228-900, Sao Jose dos Campos, SP (Brazil)

2011-03-01

339

Analysis of Series Resonant Inverter using Hysteresis Current Control  

Directory of Open Access Journals (Sweden)

Full Text Available The main objective of this paper is to analyze a series resonant inverter for industrial induction heating application. It is a process used for heat conductive materials, bond, harden, and soften metals. Resonant inverters which operate at high frequency preferable for induction heating. Series resonant inverters which is made up of Insulated Gate Bipolar Transistor (IGBT. Power control is obtained by Hysteresis Current Control (HCC. Soft switching techniques is performed which minimizes switching losses.

R.Nithya

2014-02-01

340

Analysis on electronic control unit of continuously variable transmission  

Science.gov (United States)

Continuously variable transmission system can ensure that the engine work along the line of best fuel economy, improve fuel economy, save fuel and reduce harmful gas emissions. At the same time, continuously variable transmission allows the vehicle speed is more smooth and improves the ride comfort. Although the CVT technology has made great development, but there are many shortcomings in the CVT. The CVT system of ordinary vehicles now is still low efficiency, poor starting performance, low transmission power, and is not ideal controlling, high cost and other issues. Therefore, many scholars began to study some new type of continuously variable transmission. The transmission system with electronic systems control can achieve automatic control of power transmission, give full play to the characteristics of the engine to achieve optimal control of powertrain, so the vehicle is always traveling around the best condition. Electronic control unit is composed of the core processor, input and output circuit module and other auxiliary circuit module. Input module collects and process many signals sent by sensor and , such as throttle angle, brake signals, engine speed signal, speed signal of input and output shaft of transmission, manual shift signals, mode selection signals, gear position signal and the speed ratio signal, so as to provide its corresponding processing for the controller core.

Cao, Shuanggui

341

An analysis of tower (local) controller-pilot voice communications  

Science.gov (United States)

The purpose was to examine current pilot-controller communication practices in the terminal environment. Forty-nine hours of voice tapes from local positions in ten air traffic control towers (ATCTs) were examined. There were 8444 controller-to-pilot messages (e.g., clearances to takeoff or land, instructions to hold short or change radio frequencies, etc.) examined. The complexity of the controller's message (i.e., the number of pieces of information) was examined and the number of erroneous readbacks and pilot requests for repeats were analyzed as a function of message complexity. Pilot acknowledgements were also analyzed; the numbers of full and partial readbacks and acknowledgements only (i.e., 'roger') were tallied. Fewer than one percent of the messages resulted in communications errors. Among the error factors examined were: complexity of the message, type of acknowledgement, use of call sign in the acknowledgement, type of information in error, and whether or not the controller responded to the readback error. Instances in which the controller contacted the aircraft with one call sign and the pilot acknowledged the transmission with another call sign were also examined. The report concludes with recommendations to further reduce the probability of communication errors.

Cardosi, Kim M.

1994-06-01

342

Control-flow analysis of function calls and returns by abstract interpretation  

DEFF Research Database (Denmark)

We derive a control-flow analysis that approximates the interprocedural control-flow of both function calls and returns in the presence of first-class functions and tail-call optimization. In addition to an abstract environment, our analysis computes for each expression an abstract control stack, effectively approximating where function calls return across optimized tail calls. The analysis is systematically calculated by abstract interpretation of the stack-based CaEK abstract machine of Flanagan et al. using a series of Galois connections. Abstract interpretation provides a unifying setting in which we 1) prove the analysis equivalent to the composition of a continuation-passing style (CPS) transformation followed by an abstract interpretation of a stack-less CPS machine, and 2) extract an equivalent constraint-based formulation, thereby providing a rational reconstruction of a constraint-based control-flow analysis from abstract interpretation principles.

Midtgaard, Jan; Jensen, Thomas P.

2009-01-01

343

Nuclear power plant control room task analysis. Pilot study for pressurized water reactors  

International Nuclear Information System (INIS)

The purposes of this nuclear plant task analysis pilot study: to demonstrate the use of task analysis techniques on selected abnormal or emergency operation events in a nuclear power plant; to evaluate the use of simulator data obtained from an automated Performance Measurement System to supplement and validate data obtained by traditional task analysis methods; and to demonstrate sample applications of task analysis data to address questions pertinent to nuclear power plant operational safety: control room layout, staffing and training requirements, operating procedures, interpersonal communications, and job performance aids. Five data sources were investigated to provide information for a task analysis. These sources were (1) written operating procedures (event-based); (2) interviews with subject matter experts (the control room operators); (3) videotapes of the control room operators (senior reactor operators and reactor operators) while responding to each event in a simulator; (4) walk-/talk-throughs conducted by control room operators for each event; and (5) simulator data from the PMS

344

Analysis of modern optimal control theory applied to plasma position and current control in TFTR  

International Nuclear Information System (INIS)

The strong compression TFTR discharge has been segmented into regions where linear dynamics can approximate the plasma's interaction with the OH and EF power supply systems. The dynamic equations for these regions are utilized within the linear optimal control theory framework to provide active feedback gains to control the plasma position and current. Methods are developed to analyze and quantitatively evaluate the quality of control in a nonlinear, more realistic simulation. Tests are made of optimal control theory's assumptions and requirements, and the feasibility of this method for TFTR is assessed

345

Analysis and control of low-speed forced unsteady flow  

Science.gov (United States)

A capability for numerically simulating 2-D flows in temporally deforming geometries is described, with emphasis on flow with forced unsteadiness, particularly on the simulation and analysis of these flows. The simulation of forced unsteady flows makes the examination of fundamental unsteady flow mechanisms, such as dynamic stall and unsteady separation, possible. A turbulence model is being incorporated into the analysis so as to obtain solutions for the higher Reynolds numbers used in the experiments. The analysis is also of utility in studying fluid-structure interactions, free surfaces, metal-forming, and bio-fluid mechanics involving flow through passages with flexible walls.

Ghia, U.; Ghia, K. N.

1990-01-01

346

Analysis of Control Strategies for Aircraft Flight Upset Recovery  

Science.gov (United States)

This paper proposes a framework for studying the ability of a control strategy, consisting of a control law and a command law, to recover an aircraft from ight conditions that may extend beyond the normal ight envelope. This study was carried out (i) by evaluating time responses of particular ight upsets, (ii) by evaluating local stability over an equilibrium manifold that included stall, and (iii) by bounding the set in the state space from where the vehicle can be safely own to wings-level ight. These states comprise what will be called the safely recoverable ight envelope (SRFE), which is a set containing the aircraft states from where a control strategy can safely stabilize the aircraft. By safe recovery it is implied that the tran- sient response stays between prescribed limits before converging to a steady horizontal ight. The calculation of the SRFE bounds yields the worst-case initial state corresponding to each control strategy. This information is used to compare alternative recovery strategies, determine their strengths and limitations, and identify the most e ective strategy. In regard to the control law, the authors developed feedback feedforward laws based on the gain scheduling of multivariable controllers. In regard to the command law, which is the mechanism governing the exogenous signals driving the feed- forward component of the controller, we developed laws with a feedback structure that combines local stability and transient response considera- tions. The upset recovery of the Generic Transport Model, a sub-scale twin-engine jet vehicle developed by NASA Langley Research Center, is used as a case study.

Crespo, Luis G.; Kenny, Sean P.; Cox, David E.; Muri, Daniel G.

2012-01-01

347

Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control  

International Nuclear Information System (INIS)

The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calccharacteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)

348

Analysis of Fusion Burn Control Approaches Using METIS  

Science.gov (United States)

Controlling the fusion power through regulation of the plasma density and temperature is one of the most fundamental problems in fusion reactors and will be critical to the success of burning plasma experiments like ITER. In this work, a volume averaged model for the evolution of the density of energy, deuterium and tritium fuel ions, alpha-particles, and impurity ions is used to synthesize nonlinear feedback controllers for stabilizing and modulating the burn condition. Adaptive control techniques are used to account for modeling uncertainty. The control approaches make use of the different possible methods for altering the fusion power, including adjusting the temperature through auxiliary heating, modulating the density or isotopic mix through fueling, and altering the impurity density through impurity injection. The different methods are simulated and compared using a simulation framework based around METIS, a module of the CRONOS code. The simulations include the effects of 1D plasma profiles and particle recycling, and the framework allows for testing the robustness and performance of the controllers in various scenarios, including confinement changes, impurity content changes, and actuators faults.

Boyer, Mark; Schuster, Eugenio; Bremond, Sylvain; Nouailletas, Remy; Artaud, Jean-Francois

2012-10-01

349

Analysis and Synthesis of the SNS Superconducting RF Control System  

CERN Document Server

The RF system for the SNS superconducting linac consists of a superconducting cavity, a klystron, and a low-level RF (LLRF) control system. For a proton linac like SNS, the field in each individual cavity needs to be controlled to meet the overall system requirements. The purpose of the LLRF control system is to maintain the RF cavity field to a desired magnitude and phase by controlling the klystron driver signal. The Lorentz force detuning causes the shift of the resonant frequency during the normal operation in the order of a few hundreds hertz. In order to compensate the Lorentz force detuning effects, the cavity is pre-tuned into the middle of the expected frequency shift caused by the Lorentz force detuning. Meanwhile, to reduce the overshoot in the transient response, a feed-forward algorithm, a linear parameter varying gain scheduling (LPV-GS) controller, is proposed to get away a repetitive noised caused by the pulsed operation as well as the Lorentz force detuning effects.

Wang, Y M; Regan, A H

2000-01-01

350

Control system model for the SASSYS-1 systems analysis code  

International Nuclear Information System (INIS)

A general control system model has been coupled with SASSYS-1 one-dimensional liquid-metal reactor (LMR) thermal-hydraulics code to provide an integrated treatment for LMRs similar to the general control system/thermal-hydraulics treatment available for light water reactors in RETRAN. With the development of innovative reactor design concepts, the emphasis on LMR safety has shifted away from the consideration of hypothetical whole-core disruptive accidents (HCDAs) to transients with much milder consequences and of much longer time scale. This increase in time scale, rendered possible by the incorporation of a number of inherently safe design features, makes it important to consider the possibility of control system action in the long-term response of the plant and to ascertain that inadvertent aggravation of the transient by control action is not possible. As a step in this direction, the Argonne National Laboratory (ANL) LMR system transient code SASSYS-1, which evolved from the ANL LMR HCDA code, SAS4A, was modified to include a control system simulation module

351

Space-dependent analysis of feedback control to suppress thermal runaway by compression-decompression  

International Nuclear Information System (INIS)

Feedback stabilization of the thermal runaway by compression-decompression is studied by using a onedimensional transport model that includes the effect of plasma profiles. The stability conditions required for the control system are derived from an eigenvalue analysis. The dynamic responses of plasma parameters to the control are also studied numerically by time integrating the transport equation with locally perturbed initial conditions. The stability conditions on the feedback control system are similar to previous results obtained from the zero-dimensional analysis. Timedependent analysis shows that thermal runaway initiated by the local disturbances of temperature is suppressed, allowing a stationary burn of the spacedependent plasma

352

QUANTITATIVE RISK ANALYSIS: DETERMINING UNIVERSITY RISK MITIGATION AND CONTROL MECHANISMS  

OpenAIRE

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 cate...

Bayaga, Anass; Mtose, Xoliswa

2010-01-01

353

Effect of the A-site cation on methane oxidation of perovskite-type (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba)  

Energy Technology Data Exchange (ETDEWEB)

Perovskite-type (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba) synthesized at 700 Degree-Sign 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 m{sup 2}/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 CoO{sub 6} octahedra increased with an increase in the ionic radius of the M ion. The temperature corresponding to the 50% conversion (T{sub 1/2}) of CH{sub 4} oxidation was almost constant for the samples with x=0.04, while the T{sub 1/2} 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 CH{sub 4} to CO{sub 2} and H{sub 2}O on (La{sub 0.94}M{sub 0.06})CoO{sub 3} (M=Ca, Sr, and Ba). Highlights: Black-Right-Pointing-Pointer (La{sub 1-x}M{sub x})CoO{sub 3} (M=Ca, Sr, and Ba) was synthesized using the polymerizable complex method. Black-Right-Pointing-Pointer The Co-O distance was constant regardless of the M ion or x. Black-Right-Pointing-Pointer The Co-O-Co angle increased with an increase in the ionic radius of the M ion. Black-Right-Pointing-Pointer CH{sub 4} oxidation started above 300 Degree-Sign C and finished at 700 Degree-Sign C. Black-Right-Pointing-Pointer The catalytic activity increased with increases in the ionic radius of the M ion.

Taguchi, Hideki, E-mail: htaguchi@cc.okayama-u.ac.jp [Graduate School of Natural Science and Technology (Science), Okayama University, 3-1-1 Tsushima-Naka, Kita-Ku, Okayama 700-8530 (Japan); Matsu-ura, Keiko [Graduate School of Natural Science and Technology (Science), Okayama University, 3-1-1 Tsushima-Naka, Kita-Ku, Okayama 700-8530 (Japan); Takada, Masao; Hirota, Ken [Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyo-Tanabe 610-0321 (Japan)

2012-06-15

354

Analysis and control of a shunt active power filter  

Energy Technology Data Exchange (ETDEWEB)

This report deals with active power filtering of low-frequency current harmonics. The active filter consists of a forced-commutated voltage source inverter with a digital control system. The aim of this master thesis is to investigate the performance of a shunt active power filter, and the parameters influence on the system performance. Three different harmonic identification methods are presented and compared. The shunt active power filter is very well suited for harmonic current reduction, provided that the phase shift due to the digital implementation of the control system is compensated. The performance of the active power filter depends on the switching frequency. When using individual harmonic detection methods the amount of compensation can be fully controlled for each current harmonic.

Ottersten, R.; Petersson, Andreas [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Electric Power Engineering

1999-09-01

355

Fracture analysis for controlled blasting demolition of reinforced concrete structures  

International Nuclear Information System (INIS)

Toward establishing a design method for controlled blasting demolition used for the designed dismantling of large reinforced concrete (RC) structures, this study is intended to prove the overall suitability and efficiency of this method. The previous paper (Controlled Blasting for Demolition of Biological Shield Concrete Wall: Part 2) described an application of controlled blasting demolition to an inner part of the radioactive RC biological shield in the JPDR (Japan Power Demonstration Reactor). Through this experience, it was confirmed that the partial demolition of the structure was carried out safely and rationally using this method. In order to clarify the characteristics of blasting effect, an RC cylinder blasting test was performed and the results of this test were compared with analytical simulation of this test using the discrete element method (DEM) and the finite element method (FEM). This paper outlines the test, the analyses and the comparison. (author)

356

Identification and control of chaos in nonlinear gear dynamic systems using Melnikov analysis  

Science.gov (United States)

In this paper, the Melnikov analysis is extended to develop a practical model of gear system to control and eliminate the chaotic behavior. To this end, a nonlinear dynamic model of a spur gear pair with backlash, time-varying stiffness and static transmission error is established. Based on the Melnikov analysis the global homoclinic bifurcation and transition to chaos in this model are predicted. Then non-feedback control method is used to eliminate the chaos by applying an additional control excitation. The regions of the parameter space for the control excitation are obtained analytically. The accuracy of the theoretical predictions and also the performance of the proposed control system are verified by the comparison with the numerical simulations. The simulation results show effectiveness of the proposed control system and present some useful information to analyze and control the gear dynamical systems.

Farshidianfar, A.; Saghafi, A.

2014-10-01

357

Meta-Analysis of Randomised Controlled Trials or Observational Studies  

Directory of Open Access Journals (Sweden)

Full Text Available Observational analytical studies, especially retrospective case-control studies, are considered methodologically suspect by many investigators. In general, there are a number of limitations to the value of the results of case-control studies, and in assessing the validity of included cases and controls, a first question would be: To what extent would further follow-up alter the estimate of the association between a postulated risk factor and studied disease? In case of cohort studies, there is no bias of misclassification of individuals into exposed and unexposed. Because of their prospective nature, cohort studies are stronger than case-control studies when well executed but they also are more expensive. Moreover, cohort studies are unsuitable for uncommon diseases or diseases with low incidence in the population, and usually involve a large number of people. In theory, well designed randomised controlled clinical trials (RCTs avoid most of pitfalls of observational studies and categorized as level II or even level I evidence in case of large multicentric RCTs. It is surprising that nearly all systematic reviews, including Cochrane Collaboration reviews, concentrate on clinical trials. Little attention has been withdrawn towards the importance of pooling observational studies as cohort, case-control and ecological studies. Combining RCTs may provide more evidence; however combining data from observational studies is sometimes desirable, especially in studying the treatment of a chronic disease. In addition, identification of chronic diseases risk factors is currently the most crucial problem in the epidemiology of non-infectious diseases and calls for pooling the results of dispersed observational studies. [TAF Prev Med Bull 2010; 9(4.000: 269-270

Mohamed Farouk Allam

2010-08-01

358

CFD Analysis of Circulation Control Airfoils Using Fluent  

Science.gov (United States)

In an effort to validate computational fluid dynamics procedures for calculating flows around circulation control airfoils, the commercial flow solver FLUENT was utilized to study the flow around a general aviation circulation control airfoil. The results were compared to experimental and computational fluid dynamics results conducted at the NASA Langley Research Center. The current effort was conducted in three stages: 1. A comparison of the results for free-air conditions to those from experiments. 2. A study of wind-tunnel wall effects. and 3. A study of the stagnation-point behavior.

McGowan, Gregory; Gopalarathnam, Ashok

2005-01-01

359

Window-based congestion control : Modeling, analysis and design  

OpenAIRE

This thesis presents a model for the ACK-clock inner loop, common to virtually all Internet congestion control protocols, and analyzes the stability properties of this inner loop, as well as the stability and fairness properties of several window update mechanisms built on top of the ACK-clock. Aided by the model for the inner-loop, two new congestion control mechanisms are constructed, for wired and wireless networks. Internet traffic can be divided into two main types: TCP traffic and real-...

Mo?ller, Niels

2008-01-01

360

Metodologias de controle de qualidade de análises granulométricas do solo / Methodologies for quality control of soil particle size analysis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A qualidade da análise granulométrica é imprescindível para a adequada classificação textural dos solos e enquadramento no Zoneamento Agroclimático. O objetivo deste trabalho foi avaliar metodologias de controle de qualidade das análises granulométricas. Foram coletadas amostras de solos com diferen [...] tes texturas, as quais foram analisadas por cinco laboratórios. O controle da qualidade foi realizado utilizando duas metodologias, uma proposta pelo Instituto Agronômico de Campinas (IAC) e a outra pela Rede Oficial de Laboratórios de Análise de Solo e de Tecido Vegetal dos Estados do RS e SC (ROLAS). Verificou-se maior número de inconformidades para as frações argila e silte, independentemente do método, sendo que o método da ROLAS apresentou maior número de inconformidades (76% das amostras), principalmente para amostras com teores mais elevados dessas frações. A metodologia da ROLAS com utilização da mediana é mais rigorosa no controle da qualidade das análises. Abstract in english The quality of particle size analysis is essential for correct soil textural classification and defining the Brazilian Agroclimatic Zoning. The objectives were to evaluate methods of particle size analysis and develop a spreadsheet for use in quality control analyzes. We collected 50 soil samples wi [...] th different particle size distribution, in RS and SC states of Brazil, which were analyzed by five laboratories in the two states that perform the soil particle size analysis using two methods: one proposed by the Campinas Agronomic Institute (IAC) and the other by the Network of Soil and Plant Tissue Analysis Laboratories of the states of RS and SC (ROLAS). A greater number of disparities were observed for the clay and sand fractions regardless of the method. The ROLAS method had a higher number of mismatches (76% of samples), especially for samples with higher contents of those two fractions. The use of the median value in the ROLAS methodology is more rigorous in analysis quality control.

Vilson Antonio, Klein; Tiago, Madalosso; José Miguel, Reichert; Luis Eduardo Akiyoshi Sanches, Suzuki; Milton da, Veiga; Jackson Adriano, Albuquerque; Eloy Antonio, Pauletto.

2013-05-01

361

Identifying Controlling Variables for Math Computation Fluency Through Experimental Analysis: The Interaction of Stimulus Control and Reinforcing Consequences.  

Science.gov (United States)

This study investigated a method for conducting experimental analyses of academic responding. In the experimental analyses, academic responding (math computation), rather than problem behavior, was reinforced across conditions. Two separate experimental analyses (one with fluent math computation problems and one with non-fluent math computation problems) were conducted with three elementary school children using identical contingencies while math computation rate was measured. Results indicate that the experimental analysis with non-fluent problems produced undifferentiated responding across participants; however, differentiated responding was achieved for all participants in the experimental analysis with fluent problems. A subsequent comparison of the single-most effective condition from the experimental analyses replicated the findings with novel computation problems. Results are discussed in terms of the critical role of stimulus control in identifying controlling consequences for academic deficits, and recommendations for future research refining and extending experimental analysis to academic responding are made. PMID:25480794

Hofstadter-Duke, Kristi L; Daly, Edward J

2014-12-01

362

Material Control and Accounting Design Considerations for High-Temperature Gas Reactors  

Energy Technology Data Exchange (ETDEWEB)

The subject of this report is domestic safeguards and security by design (2SBD) for high-temperature gas reactors, focusing on material control and accountability (MC&A). The motivation for the report is to provide 2SBD support to the Next Generation Nuclear Plant (NGNP) project, which was launched by Congress in 2005. This introductory section will provide some background on the NGNP project and an overview of the 2SBD concept. The remaining chapters focus specifically on design aspects of the candidate high-temperature gas reactors (HTGRs) relevant to MC&A, Nuclear Regulatory Commission (NRC) requirements, and proposed MC&A approaches for the two major HTGR reactor types: pebble bed and prismatic. Of the prismatic type, two candidates are under consideration: (1) GA's GT-MHR (Gas Turbine-Modular Helium Reactor), and (2) the Modular High-Temperature Reactor (M-HTR), a derivative of Areva's Antares reactor. The future of the pebble-bed modular reactor (PBMR) for NGNP is uncertain, as the PBMR consortium partners (Westinghouse, PBMR [Pty] and The Shaw Group) were unable to agree on the path forward for NGNP during 2010. However, during the technology assessment of the conceptual design phase (Phase 1) of the NGNP project, AREVA provided design information and technology assessment of their pebble bed fueled plant design called the HTR-Module concept. AREVA does not intend to pursue this design for NGNP, preferring instead a modular reactor based on the prismatic Antares concept. Since MC&A relevant design information is available for both pebble concepts, the pebble-bed HTGRs considered in this report are: (1) Westinghouse PBMR; and (2) AREVA HTR-Module. The DOE Office of Nuclear Energy (DOE-NE) sponsors the Fuel Cycle Research and Development program (FCR&D), which contains an element specifically focused on the domestic (or state) aspects of SBD. This Material Protection, Control and Accountancy Technology (MPACT) program supports the present work summarized in this report, namely the development of guidance to support the consideration of MC&A in the design of both pebble-bed and prismatic-fueled HTGRs. The objective is to identify and incorporate design features into the facility design that will cost effectively aid in making MC&A more effective and efficient, with minimum impact on operations. The theft of nuclear material is addressed through both MC&A and physical protection, while the threat of sabotage is addressed principally through physical protection.

Trond Bjornard; John Hockert

2011-08-01

363

Analysis and control of excitation, field weakening and stability in direct torque controlled electrically excited synchronous motor drives  

Energy Technology Data Exchange (ETDEWEB)

Direct torque control (DTC) is a new control method for rotating field electrical machines. DTC controls directly the motor stator flux linkage with the stator voltage, and no stator current controllers are used. With the DTC method very good torque dynamics can be achieved. Until now, DTC has been applied to asynchronous motor drives. The purpose of this work is to analyse the applicability of DTC to electrically excited synchronous motor drives. Compared with asynchronous motor drives, electrically excited synchronous motor drives require an additional control for the rotor field current. The field current control is called excitation control in this study. The dependence of the static and dynamic performance of DTC synchronous motor drives on the excitation control has been analysed and a straightforward excitation control method has been developed and tested. In the field weakening range the stator flux linkage modulus must be reduced in order to keep the electro motive force of the synchronous motor smaller than the stator voltage and in order to maintain a sufficient voltage reserve. The dynamic performance of the DTC synchronous motor drive depends on the stator flux linkage modulus. Another important factor for the dynamic performance in the field weakening range is the excitation control. The field weakening analysis considers both dependencies. A modified excitation control method, which maximises the dynamic performance in the field weakening range, has been developed. In synchronous motor drives the load angle must be kept in a stabile working area in order to avoid loss of synchronism. The traditional vector control methods allow to adjust the load angle of the synchronous motor directly by the stator current control. In the DTC synchronous motor drive the load angle is not a directly controllable variable, but it is formed freely according to the motor`s electromagnetic state and load. The load angle can be limited indirectly by limiting the torque reference. This method is however parameter sensitive and requires a safety margin between the theoretical torque maximum and the actual torque limit. The DTC modulation principle allows however a direct load angle adjustment without any current control. In this work a direct load angle control method has been developed. The method keeps the drive stabile and allows the maximal utilisation of the drive without a safety margin in the torque limitation. (orig.) 39 refs.

Pyrhoenen, O.

1998-12-31

364

Analysis and control of odors from petroleum refineries  

International Nuclear Information System (INIS)

This paper presents a proven approach used to effectively solve odor problems associated with atmospheric emissions from petroleum refineries. A systematic evaluation is first conducted to identify all emissions with the potential for off-site odor impacts. Sampling is then conducted and dynamic dilution olfactometry is used to quantify the odor emission rates of each source. Community odor surveys are performed simultaneously with the source sampling to quantitatively document the downwind odor impacts. Atmospheric dispersion modeling specifically designed for odor is then used to predict instantaneous odor occurrences at various receptor sites under meteorological conditions not actually encountered during the field study. The findings make it possible to rank sources by their odor emission rates and potential for odor impacts in the community. It is then possible to determine how much odor reduction is required to bring the present odor impacts of the individual sources to an acceptable level under worst-case meteorological conditions. Once the degree of control required is determined, control alternatives are selected and evaluated. Case histories have been selected to illustrate the application of this approach at petroleum refineries. They provide descriptions of odor assessment and abatement studies conducted specifically for refinery effluent treatment plant sources as well as process unit emission sources. The sources identified as needing control and the odo identified as needing control and the odor abatement measures taken are discussed

365

Analysis and control of microstructure in binary alloys  

Science.gov (United States)

When metallic alloys solidify, various microstructures form inside the alloys. Most solidified alloys have a polycrystalline structure, which is an assembly of crystalline grains with boundaries between any two grains. Each grain is a single crystal with a unique crystalline orientation. Many physical properties of polycrystalline alloys are determined by the arrangement of these grains and grain boundaries. During solidification of a single crystal, microstructures with even smaller microscopic lengthscales form, such as dendritic and eutectic structures. The physical properties of single crystal alloys are largely influenced by the lengthscales of these structures. Therefore, the understanding and control of microstructure formation in solidification is important in order to achieve desired properties. Microstructures form while the system is not in equilibrium. What microstructures form is not based on minimization of free energy of the system, but depends on the dynamics of the solidification process, which is the focus of our study. We used an alloy model system, succinonitrile-coumarin152 (SCN-C152), to experimentally investigate dynamic selection and control of grain boundary structures and dendritic structures in binary alloys. We found that in a temperature gradient the grain boundaries drift toward the high temperature region in addition to the migration due to grain coarsening. We show how we can control grain boundary orientations by generating local temperature gradient through UV or laser heatings. We show that perturbations also permit accurate control of the microstructure within a single crystal during the directional solidification process. Dendritic patterns can be controlled either by guiding the initial formation of the pattern or by triggering subcritical transitions between stable microstructures. We also investigated the role of surface tension anisotropy on the stability of cellular/dendritic arrays using three crystals of different growth orientations with respect to the surface tension anisotropy. We found that the surface tension anisotropy affects the spacing between dendrites and stability via the surface tension perpendicular to the growth direction.

Lee, Kyuyong

366

Cost analysis of wildlife rabies and its control in Europe.  

Science.gov (United States)

Within the WHO/FAC Coordinated Research Programme on Wildlife Rabies, a comprehensive survey of all costs involved in wildlife rabies and its control was carried out from 1972 to 1974 by the Government of the Land Nordrhein-Westfalen with the support of the Government of the Federal Republic of Germany and in collaboration with the World Health Organization. For extrapolation of data, administrative costs at the level of the State government and the provinces are considered as relatively constant figures, whereas all other cost components appear to depend largely on the local epidemiological conditions in counties and communities, e.g. administrative costs at county level, cost directly related to rabies cases in animals as well as costs of medical services for episode investigation and post-exposure treatment. The economic burden of wildlife rabies was estimated for the whole Land in 1974 to be in the order of DM 4.02 million. Of this amount, DM 0.77 million concerned costs of control measures in wildlife (intensified hunting and gassing operations for fox control). Assuming use of the most efficient measures according to newer concepts of wildlife rabies control in infected areas, the total expenditure for rabies control in wildlife would have been DM 1.36 million. These costs could be paid by the savings of less than one rabies-free year. This saving in the whole Land would be in the order of DM 1.9 million under the assumption of rabies being prevalent in adjacent "Länder". The paper contains guidelines for the extrapolation of the different cost factors to other periods and European areas for comparative analyses. PMID:664978

Kahl, W; Quander, J; Posch, J; Bögel, K

1978-04-01

367

Quantitative analysis by computer controlled X-ray fluorescence spectrometer  

International Nuclear Information System (INIS)

X-ray fluorescence spectroscopy has become a widely accepted method in the metallurgical field for analysis of both minor and major elements. As encountered in many other analytical techniques, the problem of matrix effect generally known as the interelemental effects is to be dealt with effectively in order to make the analysis accurate. There are several methods by which the effects of matrix on the analyte are minimised or corrected for and the mathematical correction is one among them. In this method the characteristic secondary X-ray intensities are measured from standard samples and correction coefficients. If any, for interelemental effects are evaluated by mathematical calculations. This paper describes attempts to evaluate the correction coefficients for interelemental effects by multiple linear regression programmes using a computer for the quantitative analysis of stainless steel and a nickel base cast alloy. The quantitative results obtained using this method for a standard stainless steel sample are compared with the given certified values. (author)

368

Experimental analysis of simulated reinforcement learning control for active and passive building thermal storage inventory  

Energy Technology Data Exchange (ETDEWEB)

This paper is the second part of a two-part investigation of a novel approach to optimally control commercial building passive and active thermal storage inventory. The proposed building control approach is based on simulated reinforcement learning, which is a hybrid control scheme that combines features of model-based optimal control and model-free learning control. An experimental study was carried out to analyze the performance of a hybrid controller installed in a full-scale laboratory facility. The first paper introduced the theoretical foundation of this investigation including the fundamental theory of reinforcement learning control. This companion paper presents a discussion and analysis of the experimental results. The results confirm the feasibility of the proposed control approach. Operating cost savings were attained with the proposed control approach compared with conventional building control; however, the savings are lower than for the case of model-based predictive optimal control. As for the case of model-based predictive control, the performance of the hybrid controller is largely affected by the quality of the training model, and extensive real-time learning is required for the learning controller to eliminate any false cues it receives during the initial training period. Nevertheless, compared with standard reinforcement learning, the proposed hybrid controller is much more readily implemented in a commercial building. (author)

Liu, S. [Architectural Engineering, University of Nebraska-Lincoln, PKI 243, Omaha, NE (United States); Henze, G. P. [Architectural Engineering, University of Nebraska-Lincoln, PKI 203D, Omaha, NE (United States)

2006-07-01

369

Control and Analysis of Pulse-Modulated Systems  

OpenAIRE

The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. We also introduce the harmonic transfer function and finally we provide a summary of the appended papers. The first paper considers stability analysis of a class of pulse-width modulated syst...

Alme?r, Stefan

2008-01-01

370

Comparison of nested case-control and survival analysis methodologies for analysis of time-dependent exposure  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Epidemiological studies of exposures that vary with time require an additional level of methodological complexity to account for the time-dependence of exposure. This study compares a nested case-control approach for the study of time-dependent exposure with cohort analysis using Cox regression including time-dependent covariates. Methods A cohort of 1340 subjects with four fixed and seven time-dependent covariates was used for this study. Nested case-control analyses were repeated 100 times for each of 4, 8, 16, 32, and 64 controls per case, and point estimates were compared to those obtained using Cox regression on the full cohort. Computational efficiencies were evaluated by comparing central processing unit times required for analysis of the cohort at sizes 1, 2, 4, 8, 16, and 32 times its initial size. Results Nested case-control analyses yielded results that were similar to results of Cox regression on the full cohort. Cox regression was found to be 125 times slower than the nested case-control approach (using four controls per case. Conclusions The nested case-control approach is a useful alternative for cohort analysis when studying time-dependent exposures. Its superior computational efficiency may be particularly useful when studying rare outcomes in databases, where the ability to analyze larger sample sizes can improve the power of the study.

Platt Robert W

2005-01-01

371

Spectrometry measurement prospects for industry on-line analysis and water control  

International Nuclear Information System (INIS)

Industrial on-line control is developing; manifestation of this development is spectrometry. Application examples to complex analysis are given. Then more recent techniques of on line spectrometry with optical fibers are given

372

Randomized Algorithms for Analysis and Control of Uncertain Systems With Applications  

CERN Document Server

The presence of uncertainty in a system description has always been a critical issue in control. The main objective of Randomized Algorithms for Analysis and Control of Uncertain Systems, with Applications (Second Edition) is to introduce the reader to the fundamentals of probabilistic methods in the analysis and design of systems subject to deterministic and stochastic uncertainty. The approach propounded by this text guarantees a reduction in the computational complexity of classical  control algorithms and in the conservativeness of standard robust control techniques. The second edition has been thoroughly updated to reflect recent research and new applications with chapters on statistical learning theory, sequential methods for control and the scenario approach being completely rewritten.   Features: ·         self-contained treatment explaining Monte Carlo and Las Vegas randomized algorithms from their genesis in the principles of probability theory to their use for system analysis; ·    ...

Tempo, Roberto; Dabbene, Fabrizio

2013-01-01

373

System analysis applied for controlling the quality of metallurgical rollers  

OpenAIRE

In the work, the system analysis in the foundry where the quality management system has been implemented was described. The generalized model of the foundry’s production system was presented taking the company’s surrounding and process attitude into account.

Wojtynek, L.

2010-01-01

374

System analysis applied for controlling the quality of metallurgical rollers  

Directory of Open Access Journals (Sweden)

Full Text Available In the work, the system analysis in the foundry where the quality management system has been implemented was described. The generalized model of the foundry’s production system was presented taking the company’s surrounding and process attitude into account.

L. Wojtynek

2010-01-01

375

Ignition analysis for burn control and diagnostic developments in ITER  

International Nuclear Information System (INIS)

The temporal evolutions of the operating point during the ignition access and ignited operation phases are analysed on the basis of zero dimensional (0-D) equations in order to clarify the requirements for safe control of ignited operation and for the development of diagnostic systems in ITER. A stable and safe method of reaching the ignited operating point is identified as the 'higher temperature access' method, being compatible with the H mode power threshold constraints. It is found that the ignition boundary can be experimentally determined by a 'thermonuclear oscillation' of the operating point without knowing the power balance equation. On the other hand, the ignition boundary determined by the power balance equation has a larger error bar depending on the accuracy of the diagnostic system. The plasma waveform response to sudden changes in the various plasma parameters during ignited operation is also calculated, and fusion power regulation is demonstrated by feedback control of the fuelling and auxiliary heating power. (author)

376

Overflow risk analysis for designing a nonpoint sources control detention.  

Science.gov (United States)

This paper presents a design method by which the overflow risk related to a detention for managing nonpoint pollutant sources in urban areas can be evaluated. The overall overflow risk of a nonpoint pollutant sources control detention can be estimated by inherent overflow risk and operational overflow risk. For the purpose of calculating overflow risk, the 3-parameter mixed exponential distribution is applied to describe the probability distribution of rainfall event depth. As a rainfall-runoff calculation procedure required for deriving a rainfall capture curve, the U.S. Natural Resources Conservation Service runoff curve number method is applied to consider the nonlinearity of the rainfall-runoff relation. Finally, the detention overflow risk is assessed with respect to the detention design capacity and drainage time. The proposed overflow risk assessment is expected to provide a baseline to determine quantitative parameters in designing a nonpoint sources control detention. PMID:22852429

Choi, Chi Hyun; Cho, Seonju; Park, Moo Jong; Kim, Sangdan

2012-05-01

377

Modeling and Analysis of the DSS-14 Antenna Control System  

Science.gov (United States)

An improvement of pointing precision of the DSS-14 antenna is planned for the near future. In order to analyze the improvement limits and to design new controllers, a precise model of the antenna and the servo is developed, including a finite element model of the antenna structure and detailed models of the hydraulic drives and electronic parts. The DSS-14 antenna control system has two modes of operation: computer mode and precision mode. The principal goal of this investigation is to develop the model of the computer mode and to evaluate its performance. The DSS-14 antenna computer model consists of the antenna structure and drives in azimuth and elevation. For this model, the position servo loop is derived, and simulations of the closed-loop antenna dynamics are presented. The model is significantly different from that for the 34-m beam-waveguide antennas.

Gawronski, W.; Bartos, R.

1996-01-01

378

Comparative Analysis of the CERN Accelerator Control Systems  

CERN Document Server

In the framework of a future unique accelerator control structure for the LHC era, the convergence of the PS and SL systems was relaunched in 1997. The present study was triggered by a directive from the SL and PS Divisions to investigate and propose concrete actions. The two systems are compared in the areas of server architecture, networking capabilities including performance and flexibility, support for generic, re-configurable applications, and general purpose operator interfaces. Additional sub-systems covered by this report include the timing system software, error reporting, and the alarm sub-system. Areas where duplication of effort exists are noted, as are areas where each system could profit from the strengths of the other system. Additionally, areas are pointed out where features are missing from both systems as compared to other state- of-the-art accelerator control systems. A set of specific recommendations is proposed leading in the direction of future integration of these two systems. features ...

Watson, C

1998-01-01

379

MSFC Analysis of Thermal Control Materials on MISSE  

Science.gov (United States)

Many different passive thermal control materials were flown as part of the Materials on International Space Station Experiment, including coatings, anodizes, and multi-layer insulation materials. Engineers and scientists at the Marshall Space Flight Center have analyzed a number of these materials, including: Zinc oxide/potassium silicate coating, Zinc orthotitanate/potassium silicate coating, Sulfuric acid anodized aluminum, Various coatings for part marking, automated rendezvous and capture, and astronaut visual aids, FEP Teflon with silver/Inconel backing, and Beta cloth with and without aluminization. These and other material samples were exposed to the low Earth orbital environment of atomic oxygen, ultraviolet radiation, thermal cycling, and hard vacuum, though atomic oxygen exposure was very limited for some samples. Solar absorptance, infrared emittance, and mass measurements indicate the durability of these materials to withstand the space environment. The effect of contamination from an active space station on the performance of white thermal control coatings is discussed.

Finckenor, Miria

2006-01-01

380

Current Loop High Performance Compensation Control Strategy Analysis of Active Power Filter  

Science.gov (United States)

By particular theoretical analyzing on detection error of the traditional current loop proportion-integral (PI) controller, this paper points out the limitations of detection harmonic current at load side and proposes a current feedforward compensation controller. It can track harmonic instructions with zero static error and good compensation performance. Meanwhile, it overcomes the deficiencies of traditional load side detection harmonic current PI controller, with the traditional controller's flexibility. Even if the load harmonic current is higher than the capacity of active power filter, it can basically maintain zero static error output and has certain theoretical significance and engineering value. Theoretical analysis and simulation prove the new control strategy's correctness and effectiveness.

Yuan, Qianqian

381

A System Analysis Approach to Robot Gripper Control Using Phase Lag Compensator Bode Designs  

Science.gov (United States)

In this paper, we introduce the result comparisons that were developed for the phase lag compensator design using Bode Plots. The implementation of classical experiments as MATLAB m-files is described. Robot gripper control system can be designed to gain insight into a variety of concepts, including stabilization of unstable systems, compensation properties, Bode analysis and design. The analysis has resulted in a number of important conclusions for the design of a new generation of control support systems.

Aye, Khin Muyar; Lin, Htin; Tun, Hla Myo

2008-10-01

382

Selecting cases from nuclear families for case-control association analysis  

OpenAIRE

Abstract We examine the efficiency of a number of schemes to select cases from nuclear families for case-control association analysis using the Genetic Analysis Workshop 14 simulated dataset. We show that with this simulated dataset comparing all affected siblings with unrelated controls is considerably more powerful than all of the other approaches considered. We find that the test statistic is increased by almost 3-fold compared to the next best sampling schemes of selecting all a...

March Ruth; Zhao Jing; Pinel Tracy; Moore Rachael M; Jawaid Ansar

2005-01-01

383

Reliability analysis of the automatic control of the A-1 power plant coolant temperature  

International Nuclear Information System (INIS)

Reliability analysis of the automatic control of the A-1 reactor coolant temperature is performed taking into account the effect of both the dependent failures and the routine maintenance of control system components. In a separate supplement, reliability analysis is reported of coincidence systems of the A-1 power plant reactor. Both safe and unsafe failures are taken into consideration as well as the effect of maintenance of the respective branch elements

384

Universal Power Quality Controller Modeling and Inverters Loading Analysis  

OpenAIRE

As much as nonlinear loads and power electronics devices are more applied in power distribution systems, the importance of power quality increases. This study proposes a Universal Power Quality Conditioner (UPQC) with double-converter structure. The operation principle, the algorithm of compensation reference generation, and the control method are introduced. Computer simulation and many prototype experiments are carried out to verify the operation principle and investigate the compensation c...

Gharedaghi, F.; Jamali, H.; Deysi, M.; Khalili, A.

2011-01-01

385

Design, analysis and presentation of factorial randomised controlled trials  

OpenAIRE

Abstract Background The evaluation of more than one intervention in the same randomised controlled trial can be achieved using a parallel group design. However this requires increased sample size and can be inefficient, especially if there is also interest in considering combinations of the interventions. An alternative may be a factorial trial, where for two interventions participants are allocated to receive neither intervention, one or the other, or both. Factorial trials ...

Little Paul; Montgomery Alan A; Peters Tim J

2003-01-01

386

Observability and controllability analysis for a strapdown inertial navigation system  

OpenAIRE

In the first section a short derivation of the nonlinear inertial navigation differential equations for a strapdown inertial navigation system (SINS) represented in the geocentric, earthfixed, cartesian coordinate system (CS) is given. We restrict ourselves to 9 states for this presentation. In the second section we derive the linear inho-mogeneous inertial navigation differential equations by linearization and introduce the linearized system of algebraic observation equations. Since controll...

Dambeck, Johann H.

1995-01-01

387

The use of standards for quality control in activation analysis  

International Nuclear Information System (INIS)

The control of analytical data by randomly inserted standards or reference materials is quantified in terms of elementary statistics. The consequence of a given number of standard aliquots are interpreted on the basis of the 'a priori' expectation on the average defective fraction. It appears that, in most cases, standards serve to detect sudden large errors only. Some practical examples are considered. (author) 2 refs.; 1 fig.; 2 tabs

388

A Quality Control System using Texture Analysis in Metallurgy  

OpenAIRE

Object detection, recognition and texture classification is an important aspect of many industrial quality control systems. In this paper, we report on a system designed for the inspection of surfaces which has a range of applications in the area of metallurgy. The approach considered is based on the application of Fractal Geometry and Fuzzy Logic for texture classification and, in this paper, focuses on the manufacture of rolled steel. The manufacture of high quality metals requires automati...

Blackledge, Jonathan; Dubovitskiy, Dymitiy

2011-01-01

389

Cost analysis of NOx control alternatives for stationary gas turbines  

Energy Technology Data Exchange (ETDEWEB)

The use of stationary gas turbines for power generation has been growing rapidly with continuing trends predicted well into the future. Factors that are contributing to this growth include advances in turbine technology, operating and siting flexibility and low capital cost. Restructuring of the electric utility industry will provide new opportunities for on-site generation. In a competitive market, it maybe more cost effective to install small distributed generation units (like gas turbines) within the grid rather than constructing large power plants in remote locations with extensive transmission and distribution systems. For the customer, on-site generation will provide added reliability and leverage over the cost of purchased power One of the key issues that is addressed in virtually every gas turbine application is emissions, particularly NO{sub x} emissions. Decades of research and development have significantly reduced the NO{sub x} levels emitted from gas turbines from uncontrolled levels. Emission control technologies are continuing to evolve with older technologies being gradually phased-out while new technologies are being developed and commercialized. The objective of this study is to determine and compare the cost of NO{sub x} control technologies for three size ranges of stationary gas turbines: 5 MW, 25 MW and 150 MW. The purpose of the comparison is to evaluate the cost effectiveness and impact of each control technology as a function of turbine size. The NO{sub x} control technologies evaluated in this study include: Lean premix combustion, also known as dry low NO{sub x} (DLN) combustion; Catalytic combustion; Water/steam injection; Selective catalytic reduction (SCR)--low temperature, conventional, high temperature; and SCONO{sub x}{trademark}.

Bill Major

1999-11-05

390

Extreme value analysis for evaluating ozone control strategies  

OpenAIRE

Tropospheric ozone is one of six criteria pollutants regulated by the US EPA, and has been linked to respiratory and cardiovascular endpoints and adverse effects on vegetation and ecosystems. Regional photochemical models have been developed to study the impacts of emission reductions on ozone levels. The standard approach is to run the deterministic model under new emission levels and attribute the change in ozone concentration to the emission control strategy. However, run...

Reich, Brian; Cooley, Daniel; Foley, Kristen; Napelenok, Sergey; Shaby, Benjamin

2013-01-01

391

Analysis of Control Strategies for Diode Clamped Multilevel Inverter  

OpenAIRE

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 D...

Balamurugan, C. R.; Natarajan, S. P.; Revathy, R.

2013-01-01

392

Energy Analysis for Air Conditioning System Using Fuzzy Logic Control  

Directory of Open Access Journals (Sweden)

Full Text Available Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC. FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a thermal environmental room with a data acquisition system to monitor the temperature of the room, coefficient of performance (COP, energy consumption and energy saving. The measurements taken during the two hour experimental periods at 5-minutes interval times for temperature setpoints of 20oC, 22oC and 24oC with internal heat loads 0, 500, 700 and 1000 W. The experimental results indicate that the proposed technique can save energy in comparison with On/Off and proportional-integral-derivative (PID control.

Henry Nasution

2011-04-01

393

The role of function analysis in the ACR control centre design  

International Nuclear Information System (INIS)

An essential aspect of control centre design is the need to characterize: plant functions and their inter-relationships to support the achievement of operational goals, and roles for humans and automation in sharing and exchanging the execution of functions across all operational phases. Function analysis is a design activity that has been internationally accepted as an approach to satisfy this need. It is recognized as a fundamental and necessary component in the systematic approach to control centre design and is carried out early in the design process. A function analysis can provide a clear basis for: the control centre design for the purposes of design team communication, and customer or regulatory review, the control centre display and control systems, the staffing and layout requirements of the control centre, assessing the completeness of control centre displays and controls prior and supplementary to mock-up walkthroughs or simulator evaluations, and the design of operating procedures and training programs. This paper will explore the role for function analysis in supporting the design of the control centre. The development of the ACR control room will be used as an illustrative context for the discussion. The paper will also discuss the merits of using function analysis in a goal-or function-based approach resulting in a more robust, operationally compatible, and cost-effective design over the life of the plant. Two former papers have previously outlined, thformer papers have previously outlined, the evolution in AECL's application approach and lessons learned in applying function analysis in support of control room design. This paper provides the most recent update to this progression in application refinement. (author)

394

The Control System Modeling and The Mechanical Structure Analysis For EMCVT  

Directory of Open Access Journals (Sweden)

Full Text Available The current automotive metallic belt continuously variable transmission (CVT mostly use hydraulic system to push the cone disc and achieve the speed ratio control. A new Electrical Mechanical Continuously Variable Transmission without hydraulic control (Electrical Mechanical CVT, EMCVT studied in this paper, uses the rolling screw mechanism to press cone disc, achieves speed regulation through the electronic control mechanism, and abandons the energy-intensive hydraulic system. In this paper, based on the analysis of mechanical configuration, the EMCVT's transmission system and its speed regulation process, speed ratio control characteristic and the clamping force control feature are studied and modeled. Besides, the Control strategy of the transmission system driven by motor is built, so as to provide an important theoretical basis for the further building of EMVCT's control system and the selection and implementation of Control strategy.

Lei ZHANG

2013-07-01

395

Analysis and control of computer cooling fan noise  

Science.gov (United States)

This thesis is divided into three parts: the study of the source mechanisms and their separation, passive noise control, and active noise control. The mechanisms of noise radiated by a typical computer cooling fan is investigated both theoretically and experimentally focusing on the dominant rotor-stator interaction. The unsteady force generated by the aerodynamic interaction between the rotor blades and struts is phase locked with the blade rotation and radiates tonal noise. Experimentally, synchronous averaging with the rotation signal extracts the tones made by the deterministic part of the rotor-strut interaction mechanism. This averaged signal is called the rotary noise. The difference between the overall noise and rotary noise is defined as random noise which is broadband in the spectrum. The deterministic tonal peaks are certainly more annoying than the broadband, so the suppression of the tones is the focus of this study. Based on the theoretical study of point force formulation, methods are devised to separate the noise radiated by the two components of drag and thrust forces on blades and struts. The source separation is also extended to the leading and higher order modes of the spinning pressure pattern. By using the original fan rotor and installing it in various casings, the noise sources of the original fan are decomposed into elementary sources through directivity measurements. Details of the acoustical directivity for the original fan and its various modifications are interpreted. For the sample fan, two common features account for most of the tonal noise radiated. The two features are the inlet flow distortion caused by the square fan casing, and the large strut carrying the electric wires for the motor. When the inlet bellmouth is installed and the large strut is trimmed down to size, a significant reduction of 12 dB in tonal sound power is achieved. These structural corrections constitute the passive noise control. However, the end product still features the leading mode drag noise. Further reduction of this noise is left to the active noise control. The feasibility of the active noise control technique is demonstrated for the cancellation of both thrust and drag noise radiated at their leading modes. An open loop, feed-forward system is used to maximize the simplicity of the rig in order to deliver an appropriate technology for a small ventilation fan. (Abstract shortened by UMI.)

Wong, Kam

396

Microprocessor-based scan control unit for electron and photon beams used in surface analysis  

International Nuclear Information System (INIS)

A microprocessor-based X-Y scan control unit was developed to interface with existing PHI Scanning Auger Microprobe and exoelectron emission electronics. The unit provides precise and versatile control of the rastered beams used for surface analysis. In addition to manual control there are options for automatic line and area scans with up to 1000 discrete beam analysis points per line (up to 106 for an entire frame area) and scanning rates continuously adjustable from 1 to 2000 points per second. The design of the unit is such that it can be used in a variety of applications requiring accurate X-Y position control. This report gives a complete description of the scanning control unit's operating controls, internal programming, and circuitry

397

Microprocessor-based scan control unit for electron and photon beams used in surface analysis  

Energy Technology Data Exchange (ETDEWEB)

A microprocessor-based X-Y scan control unit was developed to interface with existing PHI Scanning Auger Microprobe and exoelectron emission electronics. The unit provides precise and versatile control of the rastered beams used for surface analysis. In addition to manual control there are options for automatic line and area scans with up to 1000 discrete beam analysis points per line (up to 10/sup 6/ for an entire frame area) and scanning rates continuously adjustable from 1 to 2000 points per second. The design of the unit is such that it can be used in a variety of applications requiring accurate X-Y position control. This report gives a complete description of the scanning control unit's operating controls, internal programming, and circuitry.

Haney, S.J.

1979-05-01

398

Robust control and analysis of a wind-diesel hybrid power plant  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this paper is twofold. First to present multivariable frequency domain techniques as a tool for controller design and dynamic analysis of an autonomous wind-diesel power system. Secondly to study how robust model based controllers can be designed for such systems.

K. Uhlen

1995-01-01

399

Robust control and analysis of a wind-diesel hybrid power plant  

OpenAIRE

The aim of this paper is twofold. First to present multivariable frequency domain techniques as a tool for controller design and dynamic analysis of an autonomous wind-diesel power system. Secondly to study how robust model based controllers can be designed for such systems.

Uhlen, K.; Foss, Bjarne A.; Gjøsæter, O. B.

1995-01-01

400

Guidelines for reliability analysis of control elements and systems of nuclear power plants  

International Nuclear Information System (INIS)

The relationship is analysed between operating failures and the control system reliability. The procedure is defined of the reliability analysis of the control system for nuclear power plants from the qualitative and quantitative points of view. The preparation of input failure data for computations is assessed. Reliability computations for nuclear power plants in the Hungarian People's Republic are still in the initial stage. (Ha)

401

Numerically Analysis of Corrosion Resistance and Control Plate  

Directory of Open Access Journals (Sweden)

Full Text Available Salt water Corrosion resistance with can potentially replace the Special marine Time applications. Corrosion is defined as the deterioration of a material, usually a metal, because of a reaction with its environment. If we expose iron or steel to air and water we can expect to see rust form in a short time, showing the familiar color of red-brown iron oxide. Depending on the environment the rust may develop in minutes. In this project corrosion resistance with salt water desalination process & analyzed for catholic production analysis various operating parameters to enhance the performance of the corrosion less analysis coating and without coating of the process experimentally and numerically by using comsol with Radiographic Testing process Best Corrosion resistance –salt Water treatment model optimum will be validated experimentally.

Mr.Sanjay Kumar.k*1

2014-06-01

402

Quality control of raw cows' milk by headspace analysis  

OpenAIRE

This study investigated whether headspace analysis of volatile components can be used for monitoring the quality of raw cows¿ milk. The detection of different quality defects caused by cows¿ feed, microbiological and chemical contamination, as well as enzymatic deterioration was studied. Fresh raw milk without quality defects was shown to always contain the same seven volatile components. It was also shown that treatments like heating and homogenization of raw milk may drastically change th...

Hettinga, K. A.; Valenberg, H. J. F.; Hooijdonk, A. C. M.

2008-01-01

403

An XML Driven Framework for Test Control and Data Analysis  

OpenAIRE

An extensible, component-based framework has been developed at Fermilab to promote software reuse and provide a common platform for developing a family of test and data analysis systems. The framework allows for configuring applications from components through the use of XML configurations. It can be easily extended by adding new components and many application independent components are already provided with the framework. The core of the system has been developed in Java w...

Nogiec, J. M.; Trombly-freytag, K.; Walbridge, D.; Desavouret, E.

2001-01-01

404

Research on the Internal Controls Efficiency of the Real Estate Enterprise Based on Factor Analysis  

OpenAIRE

In the beginning, this paper researches on the operating efficiency of the 45 Chinese Real estate listed companies through DEA method. It could use technological efficiency of these as a variables and the internal controls efficiency of the real estate enterprise to do factor analyze. Thus, we can draw of comprehensive evaluation of internal control efficiency of the Chinese real estate enterprise. Analysis shows that at the top of internal control efficiency of the real estate enter...

Li, Qingdong; Cui, Zhixin

2012-01-01

405

Performance analysis of semi-active suspension with control of variable damping and stiffness  

OpenAIRE

The problem considered in this paper is the study and the control strategy design of semi-active suspensions, featuring the regulation of both damping and stiffness. The first contribution of this paper is the introduction and the analysis of two architectures based on the use of only controllable dampers, which make possible the emulation of an ideal suspension with controllable-damping-and-stiffness. This work presents an evaluation of the performances and drawbacks achieved by such suspens...

Spelta, Cristiano; Previdi, Fabio; Savaresi, Sergio M.; Bolzern, Paolo; Cutini, Maurizio; Bisaglia, Carlo; Bertinotti, Simone

2011-01-01

406

Theoretical Analysis of the Longitudinal Behavior of an Automatically Controlled Supersonic Interceptor During the Attack Phase  

Science.gov (United States)

Theoretical analysis of the longitudinal behavior of an automatically controlled supersonic interceptor during the attack phase against a nonmaneuvering target is presented. Control of the interceptor's flight path is obtained by use of a pitch rate command system. Topics lift, and pitching moment, effects of initial tracking errors, discussion of normal acceleration limited, limitations of control surface rate and deflection, and effects of neglecting forward velocity changes of interceptor during attack phase.

Gates, Ordway B., Jr.; Woodling, C. H.

1959-01-01

407

Analysis of bilinear optimal control problems governed by evolution partial differential equations  

OpenAIRE

This thesis is devoted to the analysis of nonlinear optimal control problems governed by an evolution state equation involving a term which is bilinear in state and control. The difficulties due to nonlinearity remain, but bilinearity adds a lot of structure to the control problem under consideration. In Section 2, by using Willet and Wong inequalities we establish a priori estimates for the solutions of the state equation. These estimates allow us to prove that the state equation is well pos...

Cle?rin, Jean-marc

2009-01-01

408

Program package for control system design and analysis (DPACS/J)  

International Nuclear Information System (INIS)

In order to build an optimal control system, various methods should be applied to control system design and analysis, and many 'cut and try' procedures should be taken for persuading optimality. The useful program package (DPACS/J), which will make it easy to design, and analyze control systems, has been installed in the JAERI computer. This is the manual of DPACS/J. (author)

409

Modelling and Control of a Residential Wind/PV/Battery Hybrid Power System with Performance Analysis  

OpenAIRE

Time domain performance analysis results of a standalone hybrid system are presented based on commercial wind generator, photovoltaic generator and battery energy storage system. The hybrid system is designed and modelled using Matlab/Simulink/SimPowSys environment, a control strategy has been proposed to control the voltage DC bus and the energy flow between the different energy sources. The wind and photovoltaic generators are controlled locally to obtain the maximum power extraction, while...

Antonucci, V.; Ferraro, M.; Napoli, G.; Yasin, A.

2011-01-01

410

Development of Control Program for Plant Growth Parameter Analysis in Lowland Tropical Greenhouse  

OpenAIRE

The purpose of this project is to develop control system for environment parameter in the lowland tropical greenhouse using Microcontroller. The plant growth analysis covered both inside and outside greenhouse was presented. The controller was used to monitor the temperature, relative humidity and Vapor Pressure Deficit (VPD) in the planting of chili. The study of VPD is to show air moisture conditions for plant production while taking into account different temperature levels. The controller...

Wan Ishak, W. I.; Tan Ming Yin; Hudzari, R. M.

2011-01-01

411

Structural analysis and design of multivariable control systems: An algebraic approach  

Science.gov (United States)

The application of algebraic system theory to the design of controllers for multivariable (MV) systems is explored analytically using an approach based on state-space representations and matrix-fraction descriptions. Chapters are devoted to characteristic lambda matrices and canonical descriptions of MIMO systems; spectral analysis, divisors, and spectral factors of nonsingular lambda matrices; feedback control of MV systems; and structural decomposition theories and their application to MV control systems.

Tsay, Yih Tsong; Shieh, Leang-San; Barnett, Stephen

1988-01-01

412

Failure Mode and Effects Analysis (FMEA) of the solid state full length rod control system  

International Nuclear Information System (INIS)

The Full Length Rod Control System (FLRCS) controls the power to the rod drive mechanisms for rod movement in response to signals received from the Reactor Control System or from signals generated through Reactor Operator action. Rod movement is used to control reactivity of the reactor during plant operation. The Full Length Rod Control System is designed to perform its reactivity control function in conjunction with the Reactor Control and Protection System, to maintain the reactor core within design safety limits. By the use of a Failure Mode and Effects Analysis, it is shown that the FLRCS will perform its reactivity control functions considering the loss of single active components. That is, sufficient fault limiting control circuits are provided which blocks control rod movement and/or indicates presence of a fault condition at the Control Board. Reactor operator action or automatic reactor trip will thus mitigate the consequences of potential failure of the FLRCS. The analysis also qualitatively demonstrates the reliability of the FLRCS to perform its intended function

413

Analysis of the environmental control technology for oil shale development  

Energy Technology Data Exchange (ETDEWEB)

The environmental control technology proposed in the various oil shale projects which are under development are examined. The technologies for control of air pollution, water pollution, and for the disposal, stabilization, and vegetation of the processed shale were thoroughly investigated. Although some difficulties may be encountered in any of these undertakings, it seems clear that the air and water pollution problems can be solved to meet any applicable standard. There are no published national standards against which to judge the stabilization and vegetation of the processed shale. However, based on the goal of producing an environmentally and aesthetically acceptable finished processed shale pile, it seems probable that this can be accomplished. It is concluded that the environmental control technology is available to meet all current legal requirements. This was not the case before Colorado changed their applicable Air Pollution regulations in August of 1977; the previous ones for the oil shale region were sufficiently stringent to have caused a problem for the current stage of oil shale development. Similarly, the federal air-quality, non-deterioration regulations could be interpreted in the future in ways which would be difficult for the oil shale industry to comply with. The Utah water-quality, non-deterioration regulations could also be a problem. Thus, the only specific regulations which may be a problem are the non-deterioration parts of air and water quality regulations. The unresolved areas of environmental concern with oil shale processing are mostly for the problems not covered by existing environmental law, e.g., trace metals, polynuclear organics, ground water-quality changes, etc. These may be problems, but no evidence is yet available that these problems will prevent the successful commercialization of oil shale production.

de Nevers, N.; Eckhoff, D.; Swanson, S.; Glenne, B.; Wagner, F.

1978-02-01

414

Continuous Efforts to Develop the National System for Material Control and Accounting Training at the George Kuzmycz Training Center  

Energy Technology Data Exchange (ETDEWEB)

The George Kuzmycz Training Center (GKTC) for Physical Protection, Control and Accounting of Nuclear Materials was established in 1998 at the Kyiv Institute of Nuclear Research of the Ukrainian Academy of Sciences through the collaborative efforts of the United States and Ukraine. Later the European Commission (EC) joined the US in assisting with the Material Control and Accounting (MC&A) part of the GKTC training program. The Government of Ukraine designated the GKTC as the National Center responsible for providing training and methodological support for nuclear facilities and nuclear specialists in the Material Protection, Control and Accounting (MPC&A) area. To increase the efficiency of the State MC&A system an essential number of new regulations, norms and rules have been developed; some of them mandate regular and more intensive training of MC&A specialists in the industry - from those working at the Nuclear Regulatory Authority of Ukraine to the personnel of nuclear facilities. To meet such regulations GKTC plans to develop next year a number of training courses under the EC contract; such courses will reflect both the specifics of Ukrainian nuclear facilities and the level of expertise of the facilities’ personnel. The NDA training laboratory, established in 2003 with US DOE financial support and technical and methodological assistance, considerably expanded the GKTC’s training capabilities for MC&A programs. Next year that lab will be supplemented with a new NM Surveillance and Containment laboratory as current plans call for under the EC contract. The US DOE is also providing funding to support that project. Under the EC contract the laboratory will be equipped with state-of-the-art, advanced surveillance and containment equipment which will strengthen and expand even further the GKTC’s training capabilities and potential. This will allow GKTC to train Ukrainian nuclear industry specialists in practically all MC&A topics. Furthermore, GKTC is planning to offer already this year and to continue offering in the future, on a regular basis, the courses that have already been developed, while continuing to develop new ones. This paper briefly describes the work done to upgrade the Ukrainian MC&A system, both at the State and at the facilities’ levels, as well as the results of efforts to develop the National System for training MC&A personnel at the GKTC. It also describes problems encountered and their solution; it includes comments, suggestions and recommendations for future activities to promote and improve the nuclear material management culture in Ukraine.

Gavrilyuk, Victor I.; Kirischuk, Volodymyr; Romanova, Olena; Levina, Elena; Diakov, Oleksii; Drapey, Sergiy; Proskurin, Dmitry; Gavrilyuk-Burakova, Anna

2011-10-01

415

Analysis and Design of Embedded Controlled Parallel Resonant Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Microcontroller based constant frequency controlled full bridge LC parallel resonant converter is presented in this paper for electrolyser application. An electrolyser is a part of renewable energy system which generates hydrogen from water electrolysis. The DC power required by the electrolyser system is supplied by the DC-DC converter. Owing to operation under constant frequency, the filter designs are simplified and utilization of magnetic components is improved. This converter has advantages like high power density, low EMI and reduced switching stresses. DC-DC converter system is simulated using MATLAB, Simulink. Detailed simulation results are presented. The simulation results are compared with the experimental results.

P. CHANDRASEKHAR

2009-07-01

416

Energy Analysis of Pid Controlled Heat Pump Dryer  

OpenAIRE

In this experimental study, a heat pump dryer was designed and manufactured, in which drying air temperature was controlled PID. Manufactured heat pump dryer was tested in drying kiwi, avocado and banana from among tropical fruits and energy and exergy analyses were made. Drying air temperature changed between 40 oC - 40.2 oC while drying the tropical fruits. Before the drying process in heat pump dryer, initial moisture contents were determined as 4.31 g water / g dry matter for kiwi, 1.51 g...

Ceylan, Ilhan

2009-01-01

417

Analysis of flow instability in steam turbine control valves  

International Nuclear Information System (INIS)

With the sponsorship of Electricite de France and the French steam turbine manufacturers, the Gas Turbine Laboratory of CETIM has started a research about the unsteady phenomena of flow in control valves of steam turbines. The existence of unsteady embossment in the valve cone at rise has been as certained, and a conventional computing procedure has been applied to locate the shock waves in the valve. These shock waves may suddenly arise at some valve lifts and give way to fluttering. Valve geometries attenuating instability of flow and increasing therefore the reliability of such equipment are proposed

418

Robust stability analysis for uncertain sampled-data control systems  

International Nuclear Information System (INIS)

This paper investigates robust stability (RS) of uncertain sampled-data (SD) control systems with generalized sampled-data hold functions (GSHF). A new sufficient condition for robust stability of such systems is developed. Unlike that of most of the previous works, it directly uses the data of tile continuous-time plant and therefore it is less conservative. The condition is expressed in terms of the spectral radius of a certain matrix and is shown to l)e a uni modal function of a free parameter. Thus standard one-dimensional optimization algorithm can be used to perform the proposed test

419

Design, analysis, and control of DC-excited memory motors  

OpenAIRE

In this paper, a new type of memory motors, namely the dc-excited memory motor, is proposed and implemented. The concept of dc-excited memory is due to the nature that the magnetization level of permanent magnets (PMs) in the motor can be regulated by a temporary dc current pulse and be automatically memorized. Based on an outer-rotor doubly salient motor structure, the proposed dc-excited memory motor can offer effective and efficient online air-gap flux control. Hence, it possesses the adva...

Yu, C.; Chau, Kt

2011-01-01

420

Preparation of Radiopharmaceuticals (?): Quality Control and Chemical Analysis of Radiopharmaceuticals  

International Nuclear Information System (INIS)

In 1969 this laboratory had prepared 131 mc. of radiopharmaceuticals in total (Hippuran and other four kinds) and distributed to the major medical establishment. The quality and stability of these products were reviewed by means of radio paper partition chromatography and thin layer chromatography and results were compared to those of foreign products. Generally, the quality and stability of the product of this laboratory were better than those of the foreign product, even though the properties of the radiopharmaceutical were varied by the procedure of the preparation adopted. Various precautions for handling radiopharmaceuticals for clinical use were also described with a view of quality control and stability test there of.

421

Quality control of clinker products by SEM and XRF analysis  

International Nuclear Information System (INIS)

The microstructure and chemical properties of industrial Portland cement clinkers have been examined by SEM and XRF methods to establish the nature of the clinkers and how variations in the clinker characteristics can be used to control the clinker quality. The clinker nodules were found to show differences in the chemical composition and microstructure between the inner and outer parts of the clinker nodules. Microstructure studies of industrial Portland cement clinker have shown that the outer part of the nodules are enriched in silicate more than the inner part. There is better crystallization and larger alite crystal size in the outer part than in the inner part. The alite crystal size varied between 16.2 -46.12 ? m. The clinker chemical composition was found to affect the residual >45 ? m, where a higher belite content causes an increase in the residual >45 ? m in the the cement product and will cause a decrease in the concrete strength of the cement product. The aluminate and ferrite crystals and the microcracks within the alite crystal are clear in some clinker only. The quality of the raw material preparation, burning and cooling stages can be controlled using the microstructure of the clinker product

422

Radiological analysis for the Dhruva supplementary control room  

International Nuclear Information System (INIS)

Dhruva is a 100-MWth high flux research reactor, sited at Trombay, Mumbai. It is cooled, moderated and reflected by D2O, and has a max. thermal neutron flux of 1.8x1014 n/cm2-s. The reactor has a vertical core and uses natural uranium metal fuel clad in aluminium, and Cd shutoff rods as the primary shut-down system. The core consists of 127 fuel assemblies, each having a 7-pin uranium cluster, with a total weight of the fuel in core of about 6.5 t natural uranium. The coolant enters the core at the bottom inlet plenum and exits from the top. The reactor has a low-pressure concrete containment. In view of the recent trends in reactor safety, it has been decided to provide supplementary control room (SCC) for Dhruva from where the reactor can be tripped and the safety parameters can be monitored over a long period in case the main control room (MCR) b