You make me tired: An experimental test of the role of interpersonal operant conditioning in fatigue.

Science.gov (United States)

Lenaert, Bert; Jansen, Rebecca; van Heugten, Caroline M

2018-04-01

Chronic fatigue is highly prevalent in the general population as well as in multiple chronic diseases and psychiatric disorders. Its etiology however remains poorly understood and cannot be explained by biological factors alone. Occurring in a psychosocial context, the experience and communication of fatigue may be shaped by social interactions. In particular, interpersonal operant conditioning may strengthen and perpetuate fatigue complaints. In this experiment, individuals (N = 44) repeatedly rated their currently experienced fatigue while engaging in cognitive effort (working memory task). Subtle social reward was given when fatigue increased relative to the previous rating; or disapproval when fatigue decreased. In the control condition, only neutral feedback was given. Although all participants became more fatigued during cognitive effort, interpersonal operant conditioning led to increased fatigue reporting relative to neutral feedback. This effect occurred independently of conscious awareness. Interestingly, the experimental condition also performed worse on the working memory task. Results suggest that fatigue complaints (and cognitive performance) may become controlled by their consequences such as social reward, and not exclusively by their antecedents such as effort. Results have implications for treatment development and suggest that interpersonal operant conditioning may contribute to fatigue becoming a chronic symptom. Copyright © 2018 Elsevier Ltd. All rights reserved.

ITER Operating Limits and Conditions

International Nuclear Information System (INIS)

Ciattaglia, S.; Barabaschi, P.; Carretero, J.A.

2006-01-01

The Operating Limits and Conditions (OLCs) are operating parameters and conditions, chosen among all system/components, which together define the domain of the safe operation of ITER in all foreseen ITER status (operation, maintenance, commissioning). At the same time they are selected to guarantee the required operation flexibility which is a critical factor for the success of an experimental machine such as ITER. System and components important for personnel or public safety (Safety Important Class, SIC) are identified from the overall plant safety analysis on functional importance to safety of the components. SIC classification has to be presented already inside the preliminary safety analysis report and approved by the licensing safety authority before the relevant construction. OLCs comprise the safety limits, i.e. that if exceeded could result in a potential safety hazard, the relevant settings that determine the intervention of SIC systems and the operational limits on equipment which warn from or stop a functional departure from a planned operational status that could challenge equipment and functions. The safety limits have to indicate clearly states that leave the nominal safety state of ITER; they are derived from the safety analysis of ITER. OLCs can represent in some cases few parameters grouping together. Some operational conditions, e.g. inventories, will be controlled through no real time measurements and procedures. Operating experience from present tokamaks, in particular JET, and from nuclear plants is considered at the maximum possible extent. This paper presents the guidelines to develop the ITER OLCs with particular reference to safety limits. A few examples are reported as well as open issues on some OLCs control and measurement and the relevant R-and-D planned to solve the issues. (author)

Teaching Operant Conditioning at the Zoo.

Science.gov (United States)

Lukas, Kristen E.; Marr, M. Jackson; Maple, Terry L.

1998-01-01

Describes a partnership between Zoo Atlanta and the Georgia Institute of Technology in teaching the principles of operant conditioning to students in an experimental psychology class. Maintains that the positive training techniques used in zoos are models of applied operant conditioning. Includes a discussion of zoo training goals. (MJP)

The influence of operational conditions on radiation damage in JFET-input operational amplifiers

International Nuclear Information System (INIS)

Zheng Yuzhan; Wang Yiyuan; Chen Rui; Fei Wuxiong; Lu Wu; Ren Diyuan

2010-01-01

High- and low-dose-rate irradiation have been performed on JFET-input operational amplifiers (op-amps) with normal operational and zero biased conditions, respectively. The experimental results show that operational conditions have a great influence on the radiation effects and damage in JFET-input operational amplifiers. Under normal condition, the JFET-input op-amps have exhibited time-dependent effect (TDE); while they show enhanced low-dose-rate sensitivity (ELDRS) at zero biased condition. Compared with zero biased condition, the JFET-input op-amps would degrade more severely at normal condition for high-dose-rate irradiation; while for the low-dose-rate case, they have more degradation at normal condition. Irradiation would induce positive oxide-trapped charge and interface traps in bipolar transistors, which are the basic components in JFET-input op-amps. From the dependence of oxide trapped charge and interface traps on operational conditions, the degradation behavior is discussed. (authors)

Condition Monitoring Of Operating Pipelines With Operational Modal Analysis Application

Directory of Open Access Journals (Sweden)

Mironov Aleksey

2015-12-01

Full Text Available In the petroleum, natural gas and petrochemical industries, great attention is being paid to safety, reliability and maintainability of equipment. There are a number of technologies to monitor, control, and maintain gas, oil, water, and sewer pipelines. The paper focuses on operational modal analysis (OMA application for condition monitoring of operating pipelines. Special focus is on the topicality of OMA for definition of the dynamic features of the pipeline (frequencies and mode shapes in operation. The research was conducted using two operating laboratory models imitated a part of the operating pipeline. The results of finite-element modeling, identification of pipe natural modes and its modification under the influence of virtual failure are discussed. The work considers the results of experimental research of dynamic behavior of the operating pipe models using one of OMA techniques and comparing dynamic properties with the modeled data. The study results demonstrate sensitivity of modal shape parameters to modification of operating pipeline technical state. Two strategies of pipeline repair – with continuously condition-based monitoring with proposed technology and without such monitoring, was discussed. Markov chain reliability models for each strategy were analyzed and reliability improvement factor for proposed technology of monitoring in compare with traditional one was evaluated. It is resumed about ability of operating pipeline condition monitoring by measuring dynamic deformations of the operating pipe and OMA techniques application for dynamic properties extraction.

The absolute number of repeat operations for complex intra ...

African Journals Online (AJOL)

abdominal sepsis, questions about futility of treatment frequently arise. This study focuses specifically on patients who required two or more repeat laparotomies and describes the spectrum of disease necessitating multiple repeat laparotomies ...

Operant Conditioning and Education.

Science.gov (United States)

de Noronha, Mario

A case study of a learning disabled 8-year-old with behavior disturbancs is presented to highlight the use of operant conditioning in cutting down educational costs and easing the teacher's class management problems. (CL)

The scheduling of repeat cesarean section operations: prospective management protocol experience.

Science.gov (United States)

Read, J A

1985-03-01

There are benefits to patients and a busy obstetric service if repeat cesarean section operations are performed on a scheduled basis. Optimum management avoids prematurity and reduces the need for amniocentesis. Over a period of 20 months repeat cesarean sections were performed at Tripler Army Medical Center while a protocol with the following elements was used: (1) known last menstrual period; (2) landmarks: positive urine human chorionic gonadotropin test by 6 weeks, Doppler fetal heart tone by 12 weeks, date determination by examination before 10 weeks, fetoscope fetal heart tone by 20 weeks, and date determination by size before 30 weeks; (3) date determination by midtrimester sonogram(s); (4) normal third-trimester glucose screening; (5) biparietal diameter of 9.2 or 9.5 cm before scheduling. With two or more clinical landmarks and one date by sonogram or one landmark and date by two sonograms, elective repeat cesarean section was scheduled at 39 weeks if the biparietal diameter was greater than or equal to 9.2 cm (127). If dates by sonogram were less than dates by last menstrual period but greater than 1 week or if last menstrual period was unknown, dates by sonogram and landmarks corresponding to dates by sonogram were used to electively schedule, with biparietal diameters of 9.2 or 9.5 cm respectively required (28). If protocol criteria were not met or earlier delivery was indicated (e.g., vertical scar or diabetes), amniocentesis was performed (42), except when not possible, advisable, or refused when patients either elected labor (20) or were scheduled if three or more criteria for 40+ weeks were met (18). Of 225 patients (70.5%) scheduled by protocol (173), amniocentesis (34), or medical indication (18), 188 (58.9%) were delivered without labor. In the 147 patients (46.1%) delivered electively by protocol without labor or amniocentesis, there were no cases of respiratory distress syndrome and the mean birth weight was 3517 gm. With early care and better

Operant conditioning in the ant Myrmica sabuleti.

Science.gov (United States)

Cammaerts, M C

2004-11-30

Operant conditioning could be obtained in the ant Myrmica sabuleti by presenting to the workers, during a six-day period, an apparatus containing either sugared water or meat as a reward. The conditioning obtained using sugared water as a reward was short lasting. A reconditioning was more persistent and lasted four hours. The ants' response was very precise, since they exhibited it only in front of an apparatus identical to that used during the training phase. Operant conditioning obtained using meat as a reward was more pronounced than that obtained by using sugared water, probably because meat is more valuable as a reward than sugar for the species studied, which is essentially a carnivorous one. Such a conditioning was rather persistent. Indeed, a first operant conditioning obtained by using meat as a reward could still be detected after seven hours, and a reconditioning was still significant after eight hours. One day after this eight-hour period without rewarding the ants, the response was higher again and a further day later, it was still significant. Since the operant conditioning is easy to perform and quantify and since the ants' response is very precise, such a conditioning can be used for further studying M. sabuleti workers' visual perception.

Operant conditioning of autobiographical memory retrieval.

Science.gov (United States)

Debeer, Elise; Raes, Filip; Williams, J Mark G; Craeynest, Miet; Hermans, Dirk

2014-01-01

Functional avoidance is considered as one of the key mechanisms underlying overgeneral autobiographical memory (OGM). According to this view OGM is regarded as a learned cognitive avoidance strategy, based on principles of operant conditioning; i.e., individuals learn to avoid the emotionally painful consequences associated with the retrieval of specific negative memories. The aim of the present study was to test one of the basic assumptions of the functional avoidance account, namely that autobiographical memory retrieval can be brought under operant control. Here 41 students were instructed to retrieve personal memories in response to 60 emotional cue words. Depending on the condition, they were punished with an aversive sound for the retrieval of specific or nonspecific memories in an operant conditioning procedure. Analyzes showed that the course of memory specificity significantly differed between conditions. After the procedure participants punished for nonspecific memories retrieved significantly more specific memories compared to participants punished for specific memories. However, whereas memory specificity significantly increased in participants punished for specific memories, it did not significantly decrease in participants punished for nonspecific memories. Thus, while our findings indicate that autobiographical memory retrieval can be brought under operant control, they do not support a functional avoidance view on OGM.

78 FR 65594 - Vehicular Repeaters

Science.gov (United States)

2013-11-01

... coordinators estimate the effect on coordination fees? Does the supposed benefit that mobile repeater stations... allow the licensing and operation of vehicular repeater systems and other mobile repeaters by public... email: [email protected] or phone: 202-418- 0530 or TTY: 202-418-0432. For detailed instructions for...

Paranormal weighted conditional type operators

OpenAIRE

Estaremi, Yousef

2014-01-01

In this paper, some sub-classes of paranormal weighted conditional expectation type operators, such as *-paranormal, quasi-*-paranormal and (n; k)-quasi-*-paranormal weighted conditional expectation type opera- tors on $L^2(\\Sigma)$ are investigated. Also, some applications about the spectrum, point spectrum, joint point spectrum, approximate point spectrum and joint approximate point spectrum of these classes are presented.

The aurora at quite magnetospheric conditions: Repeatability and dipole tilt angle dependence

International Nuclear Information System (INIS)

Oznovich, I.; Eastes, R.W.; Huffman, R.E.; Tur, M.; Glaser, I.

1993-01-01

Is there a magnetospheric ground state? Do the position and size of the auroral oval depend on the magnetic dipole tilt angle at quiet magnetospheric conditions? In order to address these questions, northern hemisphere images of the aurora at 1356 Angstrom, obtained by Polar BEAR at solar minimum (beginning of 1987), were related to high temporal resolution IPM 8 measurements of the interplanetary magnetic field, to solar wind velocity, and to the ground-based activity index Kp. The first problem was addressed by a two-dimensional correlation study of the repeatability of auroral emissions in corrected geomagnetic space at conditions of minimum energy transfer from the magnetosphere. The correlation measure of auroral images was 0.6-0.85. Error simulations indicate that given the uncertainties in pixel position and intensity, the maximum expected value of the correlation measure is 0.65-0.9. The notion of a ground state magnetosphere is therefore supported by this data. Repeatability was found at the same level regardless of time or reconfigurations of the magnetosphere between images and independent of magnetic time sector. The second problem was addressed by relating latitudinal shifts of the aurora with dipole tilt angle without resorting to auroral boundary specification. This data indicate that the latitude of the continuous aurora is related to the dipole tilt angle at quiet magnetospheric conditions. In the winter hemisphere a 10 degrees increase in the dipole tilt angle causes a 1 degree decrease (increase) in the latitude of auroral emissions at noon (midnight). The magnetic local time distribution of the latitudinal shifts with dipole tilt angle support a simple model in which the dipole tilt angle determines the position of the center of the auroral circle along the magnetic meridian 1320-0120 MLT (for IMF B y positive) and does not affect its radius. 22 refs., 8 figs

ANALYSIS OF OPTIMUM OPERATING MODES OF POWER TRANSFORMERS UNDER OPERATING CONDITIONS

Directory of Open Access Journals (Sweden)

I. V. Khomenko

2016-12-01

Full Text Available Purpose. The study of parallel operation optimal modes of transformer equipment for a variety of operating conditions: same or different types of transformers, with or without reactive power flows. Methodology. Losses of energy in transformers make 30 % of all losses. Therefore the choice of the economically justified parallel operation of transformers is effective action to reduce losses. Typically, in the calculations of reactive power flows in the transformers are not taken into account. It is interesting to analyze the optimal operating conditions of transformers with and without reactive power flows. Results. Calculations for transformers in distribution networks showed that the inclusion of reactive power flows in transformers significant impact on the calculated optimum regimes of transformers.

Repeated exposure to conditioned fear stress increases anxiety and delays sleep recovery following exposure to an acute traumatic stressor

Directory of Open Access Journals (Sweden)

Benjamin N Greenwood

2014-10-01

Full Text Available Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep-wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by humans, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to either no, mild (10, or severe (100 acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced REM and NREM sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep / wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep / wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders.

Teachers and Operant Conditioning.

Science.gov (United States)

Frey, Sherman

A survey was conducted of 406 elementary, middle, and secondary school teachers to determine their understanding, acceptance, and use of the principle of operant conditioning. The treatment of data was by percent and chi square analysis primarily according to sex, experience, degree, and position. Subjects reported that a) they believed that the…

47 CFR 18.111 - General operating conditions.

Science.gov (United States)

2010-10-01

... EQUIPMENT General Information § 18.111 General operating conditions. (a) Persons operating ISM equipment... equipment otherwise complies with the rules in this part, the operator of ISM equipment that causes harmful... interference to an authorized radio station or a radiocommunication device operating in an ISM frequency band...

Operant Conditioning - Token Economy.

Science.gov (United States)

Montgomery, Jacqueline; McBurney, Raymond D.

Described is an Operant Conditioning-Token Economy Program, teaching patients to be responsible for their own behavior, to make choices, and to be motivated to change. The program was instigated with mentally ill patients in a state hospital and was later used with institutionalized mentally handicapped groups. After two years, only four of the…

Role of memory errors in quantum repeaters

International Nuclear Information System (INIS)

Hartmann, L.; Kraus, B.; Briegel, H.-J.; Duer, W.

2007-01-01

We investigate the influence of memory errors in the quantum repeater scheme for long-range quantum communication. We show that the communication distance is limited in standard operation mode due to memory errors resulting from unavoidable waiting times for classical signals. We show how to overcome these limitations by (i) improving local memory and (ii) introducing two operational modes of the quantum repeater. In both operational modes, the repeater is run blindly, i.e., without waiting for classical signals to arrive. In the first scheme, entanglement purification protocols based on one-way classical communication are used allowing to communicate over arbitrary distances. However, the error thresholds for noise in local control operations are very stringent. The second scheme makes use of entanglement purification protocols with two-way classical communication and inherits the favorable error thresholds of the repeater run in standard mode. One can increase the possible communication distance by an order of magnitude with reasonable overhead in physical resources. We outline the architecture of a quantum repeater that can possibly ensure intercontinental quantum communication

Efficient quantum repeater with respect to both entanglement-concentration rate and complexity of local operations and classical communication

Science.gov (United States)

Su, Zhaofeng; Guan, Ji; Li, Lvzhou

2018-01-01

Quantum entanglement is an indispensable resource for many significant quantum information processing tasks. However, in practice, it is difficult to distribute quantum entanglement over a long distance, due to the absorption and noise in quantum channels. A solution to this challenge is a quantum repeater, which can extend the distance of entanglement distribution. In this scheme, the time consumption of classical communication and local operations takes an important place with respect to time efficiency. Motivated by this observation, we consider a basic quantum repeater scheme that focuses on not only the optimal rate of entanglement concentration but also the complexity of local operations and classical communication. First, we consider the case where two different two-qubit pure states are initially distributed in the scenario. We construct a protocol with the optimal entanglement-concentration rate and less consumption of local operations and classical communication. We also find a criterion for the projective measurements to achieve the optimal probability of creating a maximally entangled state between the two ends. Second, we consider the case in which two general pure states are prepared and general measurements are allowed. We get an upper bound on the probability for a successful measurement operation to produce a maximally entangled state without any further local operations.

Beyond Extinction: Prolonged Conditioning and Repeated Threat Exposure Abolish Contextual Renewal of Fear-Potentiated Startle Discrimination but Leave Expectancy Ratings Intact.

Science.gov (United States)

Leer, Arne; Haesen, Kim; Vervliet, Bram

2018-01-01

Extinction treatments decrease fear via repeated exposures to the conditioned stimulus (CS) and are associated with a return of fear. Alternatively, fear can be reduced via reductions in the perceived intensity of the unconditioned stimulus (US), e.g., through repeated exposures to the US. Promisingly, the few available studies show that repeated US exposures outperform standard extinction. US exposure treatments can decrease fear via two routes: (1) by weakening the CS-US association (extinction-like mechanism), and/or (2) by weakening the subjective US aversiveness (habituation-like mechanism). The current study further investigated the conditions under which US exposure treatment may reduce renewal, by adding a group in which CS-US pairings continued following fear acquisition. During acquisition, participants learned that one of two visual stimuli (CS+/CS-) predicted the occurrence of an aversive electrocutaneous stimulus (US). Next, the background context changed and participants received one of three interventions: repeated CS exposures, (2) repeated US exposures, or (3) continued CS-US pairings. Following repeated CS exposures, test presentations of the CSs in the original conditioning context revealed intact CS+/CS- differentiation in the fear-potentiated startle reflex, while the differentiation was abolished in the other two groups. Differential US expectancy ratings, on the other hand, were intact in all groups. Skin conductance data were inconclusive because standard context renewal following CS exposures did not occur. Unexpectedly, there was no evidence for a habituation-like process having taken place during US exposures or continued CS-US pairings. The results provide further evidence that US exposures outperform the standard extinction treatment and show that effects are similar when US exposures are part of CS-US pairings.

Coexistence of 3G repeaters with LTE base stations.

Science.gov (United States)

Yeo, Woon-Young; Lee, Sang-Min; Hwang, Gyung-Ho; Kim, Jae-Hoon

2013-01-01

Repeaters have been an attractive solution for mobile operators to upgrade their wireless networks at low cost and to extend network coverage effectively. Since the first LTE commercial deployment in 2009, many mobile operators have launched LTE networks by upgrading their 3G and legacy networks. Because all 3G frequency bands are shared with the frequency bands for LTE deployment and 3G mobile operators have an enormous number of repeaters, reusing 3G repeaters in LTE networks is definitely a practical and cost-efficient solution. However, 3G repeaters usually do not support spatial multiplexing with multiple antennas, and thus it is difficult to reuse them directly in LTE networks. In order to support spatial multiplexing of LTE, the role of 3G repeaters should be replaced with small LTE base stations or MIMO-capable repeaters. In this paper, a repeater network is proposed to reuse 3G repeaters in LTE deployment while still supporting multilayer transmission of LTE. Interestingly, the proposed network has a higher cluster throughput than an LTE network with MIMO-capable repeaters.

Third-order operator-differential equations with discontinuous coefficients and operators in the boundary conditions

Directory of Open Access Journals (Sweden)

Araz R. Aliev

2013-10-01

Full Text Available We study a third-order operator-differential equation on the semi-axis with a discontinuous coefficient and boundary conditions which include an abstract linear operator. Sufficient conditions for the well-posed and unique solvability are found by means of properties of the operator coefficients in a Sobolev-type space.

WORK CONDITIONS OF CHAINSAW OPERATORS

Directory of Open Access Journals (Sweden)

Jorge Roberto Malinovski

2002-01-01

Full Text Available The objective of this research was to analyze the human factors and the work conditions in clear-cutting operations using chainsaws in mountainous areas. Data were colected in a forestry company in Minas Gerais, Brazil, by interviews with 29 chainsaw operators. The results indicated that the operators average age was 32.3 years, height 1.68m and body weight 64.4Kg. The average job time in the company was 112 months and the average time of chainsaw operation experience was 81.5 months. Most (93.1% were dexterous and 6.9% were left-handed. The high incidence of backache (41.4% indicated that the task demands an overload of lumbar column, so that the company should take preventive measures to avoid backaches, using educational strategies or changing the opera-tional system. The high level of accidents (44.8% indicated that some precautions are needed to im-prove work safety.

Analysis of the repeatability of the exhaust pollutants emission research results for cold and hot starts under controlled driving cycle conditions.

Science.gov (United States)

Jaworski, Artur; Kuszewski, Hubert; Ustrzycki, Adam; Balawender, Krzysztof; Lejda, Kazimierz; Woś, Paweł

2018-04-20

Measurement of car engines exhaust pollutants emissions is very important because of their harmful effects on the environment. This article presents the assessment of repeatability of the passenger car engine exhaust pollutants emission research results obtained in the conditions of a chassis dynamometer. The research was conducted in a climate chamber, enabling the temperature conditions to be determined from - 20 to + 30 °C. The emission of CO, CH 4 , CO 2 , NO X , THC, and NMHC was subjected to the analysis. The aim of the research is to draw attention to the accuracy of the pollutant emission research results in driving cycles, and the comparison of pollutant emission results and their repeatability obtained in successive NEDC cycles under cold and hot start conditions. The results of the analysis show that, in the case of a small number of measurements, the results repeatability analysis is necessary for a proper interpretation of the pollutant emission results on the basis of the mean value. According to the authors' judgment, it is beneficial to determine the coefficient of variation for a more complete assessment of exhaust emission result repeatability obtained from a small number of measurements. This parameter is rarely presented by the authors of papers on exhaust components emission research.

A novelty detection diagnostic methodology for gearboxes operating under fluctuating operating conditions using probabilistic techniques

Science.gov (United States)

Schmidt, S.; Heyns, P. S.; de Villiers, J. P.

2018-02-01

In this paper, a fault diagnostic methodology is developed which is able to detect, locate and trend gear faults under fluctuating operating conditions when only vibration data from a single transducer, measured on a healthy gearbox are available. A two-phase feature extraction and modelling process is proposed to infer the operating condition and based on the operating condition, to detect changes in the machine condition. Information from optimised machine and operating condition hidden Markov models are statistically combined to generate a discrepancy signal which is post-processed to infer the condition of the gearbox. The discrepancy signal is processed and combined with statistical methods for automatic fault detection and localisation and to perform fault trending over time. The proposed methodology is validated on experimental data and a tacholess order tracking methodology is used to enhance the cost-effectiveness of the diagnostic methodology.

Repeatability of road pavement condition assessment based on three-dimensional analysis of linear accelerations of vehicles

Science.gov (United States)

Staniek, Marcin

2018-05-01

The article provides a discussion concerning a tool used for road pavement condition assessment based on signals of linear accelerations recorded with high sampling frequency for typical vehicles traversing the road network under real-life road traffic conditions. Specific relationships have been established for the sake of road pavement condition assessment, including identification of road sections of poor technical condition. The data thus acquired have been verified with regard to repeatability of estimated road pavement assessment indices. The data make it possible to describe the road network status against an area in which users of the system being developed move. What proves to be crucial in the assessment process is the scope of the data set based on multiple transfers within the road network.

A minicomputer interface for realtime operations: an application to operant conditioning.

Science.gov (United States)

Mayor, S J; Wilson, J

1975-09-01

A PDP-12 interface was designed, constructed, and tested for realtime imput and output of binary information. Within limits this interface can be used with any peripheral device which operates in the binary mode. In addition to its generality of application the interface features include ease of expansion and low cost. A description of its design and operation is give here is terms of a typical application: the control of behavioral equipment (i.e. "Skinner Boxes") for operant conditioning.

Condition Monitoring Of Operating Pipelines With Operational Modal Analysis Application

OpenAIRE

Mironov Aleksey; Doronkin Pavel; Priklonsky Aleksander; Kabashkin Igor

2015-01-01

In the petroleum, natural gas and petrochemical industries, great attention is being paid to safety, reliability and maintainability of equipment. There are a number of technologies to monitor, control, and maintain gas, oil, water, and sewer pipelines. The paper focuses on operational modal analysis (OMA) application for condition monitoring of operating pipelines. Special focus is on the topicality of OMA for definition of the dynamic features of the pipeline (frequencies and mode shapes) i...

Operating conditions of steam generators for LMFBR's

Energy Technology Data Exchange (ETDEWEB)

Ratzel, W

1975-07-01

Operating conditions considered to be appropriate for a LMFBR steam generator are discussed on the example of the SNR 300. The areas covered are steady state and transient conditions, upset and emergency temperature transients, and requirements due to sodium-water reactions. (author)

Operating conditions of steam generators for LMFBR's

International Nuclear Information System (INIS)

Ratzel, W.

1975-01-01

Operating conditions considered to be appropriate for a LMFBR steam generator are discussed on the example of the SNR 300. The areas covered are steady state and transient conditions, upset and emergency temperature transients, and requirements due to sodium-water reactions. (author)

Condition Monitoring of Machinery in Non-Stationary Operations : Proceedings of the Second International Conference "Condition Monitoring of Machinery in Non-Stationnary Operations"

CERN Document Server

Bartelmus, Walter; Chaari, Fakher; Zimroz, Radoslaw; Haddar, Mohamed

2012-01-01

Condition monitoring of machines in non-stationary operations (CMMNO) can be seen as the major challenge for research in the field of machinery diagnostics. Condition monitoring of machines in non-stationary operations is the title of the presented book and the title of the Conference held in Hammamet - Tunisia March 26 – 28, 2012. It is the second conference under this title, first took place in Wroclaw - Poland , March 2011. The subject CMMNO comes directly from industry needs and observation of real objects. Most monitored and diagnosed objects used in industry works in non-stationary operations condition. The non-stationary operations come from fulfillment of machinery tasks, for which they are designed for. All machinery used in different kind of mines, transport systems, vehicles like: cars, buses etc, helicopters, ships and battleships and so on work in non-stationary operations. The papers included in the book are shaped by the organizing board of the conference and authors of the papers. The papers...

Repeated research of biodegradability of plastics materials in real composting conditions

Directory of Open Access Journals (Sweden)

Dana Adamcová

2013-01-01

Full Text Available The aim of this paper was to verify information obtained by repeated research provide in 2011 and 2012 in real composting conditions and check information about biodegradability of plastics bags in real composting conditions. In both cases samples were placed into frames and inserted into one clamp within the compost pile to investigate the biodegradation. The plastics bags were obtained from chain stores in the Czech Republic and Poland. The shopping bags were made of HDPE with the TDPA additive (sample 2, PP with an addition of pro-oxidants (d2w (sample 1, 3 and materials certified as compostable (starch, polycaprolactone (sample 4, 5, 6, 7. Control sample (cellulose filtering paper, sample 8 was to check the potential of biological decomposition in the tested environment. At the end of the 15-week experimental period it was found that the polyethylene samples with the additive (sample 1, 2, 3 had not been decomposed, their colour had not changed and that no degradation neither physical changes had occurred (did not biodegrade. Samples certified as compostable (sample 4, 5, 6, 7 were decomposed. The results at the municipal compost facility demonstrate that the compostable plastics biodegrade and polyethylene samples with the additive did not biodegrade in compost.

Remaining useful life estimation for deteriorating systems with time-varying operational conditions and condition-specific failure zones

Directory of Open Access Journals (Sweden)

Li Qi

2016-06-01

Full Text Available Dynamic time-varying operational conditions pose great challenge to the estimation of system remaining useful life (RUL for the deteriorating systems. This paper presents a method based on probabilistic and stochastic approaches to estimate system RUL for periodically monitored degradation processes with dynamic time-varying operational conditions and condition-specific failure zones. The method assumes that the degradation rate is influenced by specific operational condition and moreover, the transition between different operational conditions plays the most important role in affecting the degradation process. These operational conditions are assumed to evolve as a discrete-time Markov chain (DTMC. The failure thresholds are also determined by specific operational conditions and described as different failure zones. The 2008 PHM Conference Challenge Data is utilized to illustrate our method, which contains mass sensory signals related to the degradation process of a commercial turbofan engine. The RUL estimation method using the sensor measurements of a single sensor was first developed, and then multiple vital sensors were selected through a particular optimization procedure in order to increase the prediction accuracy. The effectiveness and advantages of the proposed method are presented in a comparison with existing methods for the same dataset.

Operational Markov Condition for Quantum Processes

Science.gov (United States)

Pollock, Felix A.; Rodríguez-Rosario, César; Frauenheim, Thomas; Paternostro, Mauro; Modi, Kavan

2018-01-01

We derive a necessary and sufficient condition for a quantum process to be Markovian which coincides with the classical one in the relevant limit. Our condition unifies all previously known definitions for quantum Markov processes by accounting for all potentially detectable memory effects. We then derive a family of measures of non-Markovianity with clear operational interpretations, such as the size of the memory required to simulate a process or the experimental falsifiability of a Markovian hypothesis.

Univalence Conditions Related to a General Integral Operator

Directory of Open Access Journals (Sweden)

Nicoleta Breaz

2012-01-01

Full Text Available We consider a general integral operator based on two types of analytic functions, namely, regular functions and, respectively, functions having a positive real part. Some univalence conditions for this integral operator are obtained.

Spontaneous decisions and operant conditioning in fruit flies.

Science.gov (United States)

Brembs, Björn

2011-05-01

Already in the 1930s Skinner, Konorski and colleagues debated the commonalities, differences and interactions among the processes underlying what was then known as "conditioned reflexes type I and II", but which is today more well-known as classical (Pavlovian) and operant (instrumental) conditioning. Subsequent decades of research have confirmed that the interactions between the various learning systems engaged during operant conditioning are complex and difficult to disentangle. Today, modern neurobiological tools allow us to dissect the biological processes underlying operant conditioning and study their interactions. These processes include initiating spontaneous behavioral variability, world-learning and self-learning. The data suggest that behavioral variability is generated actively by the brain, rather than as a by-product of a complex, noisy input-output system. The function of this variability, in part, is to detect how the environment responds to such actions. World-learning denotes the biological process by which value is assigned to environmental stimuli. Self-learning is the biological process which assigns value to a specific action or movement. In an operant learning situation using visual stimuli for flies, world-learning inhibits self-learning via a prominent neuropil region, the mushroom-bodies. Only extended training can overcome this inhibition and lead to habit formation by engaging the self-learning mechanism. Self-learning transforms spontaneous, flexible actions into stereotyped, habitual responses. Copyright © 2011 Elsevier B.V. All rights reserved.

Dividing Attention Increases Operational Momentum

Directory of Open Access Journals (Sweden)

Koleen McCrink

2017-12-01

Full Text Available When adding or subtracting two quantities, adults often compute an estimated outcome that is larger or smaller, respectively, than the actual outcome, a bias referred to as “operational momentum”. The effects of attention on operational momentum were investigated. Participants viewed a display in which two arrays of objects were added, or one array was subtracted from another array, and judged whether a subsequent outcome (probe array contained the correct or incorrect number of objects. In a baseline condition, only the arrays to be added or subtracted were viewed. In divided attention conditions, participants simultaneously viewed a sequence of colors or shapes, and judged which color (a non-spatial judgment or shape (a spatial judgment was repeated. Operational momentum occurred in all conditions, but was higher in divided attention conditions than in the baseline condition, primarily for addition problems. This pattern suggests that dividing attention, rather than decreasing operational momentum by decreasing attentional shifts, actually increased operational momentum. These results are consistent with a heightened use of arithmetic heuristics under conditions of divided attention.

Acetylcholine release in the hippocampus during the operant conditioned reflex and the footshock stimulus in rats.

Science.gov (United States)

Dong, Yu; Mao, Jianjun; Shangguan, Dihua; Zhao, Rui; Liu, Guoquan

2004-10-14

The activity of the septo-hippocampal cholinergic pathway was investigated by measuring changes in the extracellular acetylcholine (ACh) levels in the hippocampus, by means of microdialysis, during the operant conditioned reflex and the repeated footshock stimulus. Microdialysis samplings were conducted in a Skinner box where lights were delivered as conditioned stimuli (CS) paired with footshocks as unconditioned stimuli (US). Two groups of rats were used. Extracellular ACh and choline (Ch) in samples collected at 6min intervals were assessed by high-performance liquid chromatography with electrochemical detection. The elevation of hippocampus ACh was observed in the two experimental groups. The increase in ACh during aversive stimulus (footshock) was significantly larger and was probably related to the number of footshocks. There might be moderate increase in the hippocampal ACh release during the retrieval of information. The concentration of choline showed no significant fluctuation in the two groups during the whole process. This experiment explored in more detail hippocampal cholinergic activity in relation to the two different procedures.

Infant Operant Conditioning and Its Implications for Early Intervention.

Science.gov (United States)

Lancioni, Giullo E.

1980-01-01

In this article infant operant conditioning studies are grouped according to distinct procedures: free operant; discrete trial with one discriminative stimulus; discrete trial with two or more discriminative stimuli; controlled operant with two or more discriminative stimuli; and unrestricted operant with two or more discriminative stimuli.…

Fungal endophthalmitis caused by Paecilomyces variotii following cataract surgery: a presumed operating room air-conditioning system contamination.

Science.gov (United States)

Tarkkanen, Ahti; Raivio, Virpi; Anttila, Veli-Jukka; Tommila, Petri; Ralli, Reijo; Merenmies, Lauri; Immonen, Ilkka

2004-04-01

To report a case of delayed fungal endophthalmitis by Paecilomyces variotii following uncomplicated cataract surgery. To our knowledge this is the first reported case of postoperative endophthalmitis by this species. We report the longterm clinical follow-up of an 83-year-old female who underwent uncomplicated sutureless, small-incision cataract surgery. She developed recurring uveitis 4 months after surgery. Vitreous tap and finally complete vitrectomy with removal of the capsular bag including the intraocular lens were performed. Fungi were studied by histopathology and culture. At histopathological examination, the fungi were found to be closely related with the capsular bag. A few mononuclear inflammatory cells were encountered. At culture, Paecilomyces variotii, a common ubiquitous non-pathogenic saprophyte, was identified. Despite systemic, intravitreal and topical antifungal therapy after vitrectomy the uveitis recurred several times, but no fungal organisms were isolated from the repeat intraocular specimen. At 18 months postoperatively the subject's visual acuity was finger counting at 2 metres. At the time of surgery the operating room air-conditioning system was undergoing repairs. Cases of fungal endophthalmitis after contamination from air-conditioning ventilation systems have been reported before, but none of the cases reported have been caused by P. variotii. P. variotii, a non-pathogenic environmental saprophyte, may be disastrous if introduced into the eye. International recommendations on the environmental control of the operating room air-conditioning ventilation system should be strictly followed. No intraoperative surgery should be undertaken while the air-conditioning system is undergoing repairs or service.

Welded repair joints of boiler steels following operation in creep conditions exceeding the design time of operation

Energy Technology Data Exchange (ETDEWEB)

Dobrzanski, J.; Paszkowska, H.; Zielinski, A. [Institute for Ferrous Metallurgy, Gliwice (Poland)

2010-07-01

The assessment of suitability for further operation for materials and welded repair joints of thick-walled main steam pipeline components, made of steel 14MoV63, as well as steam superheater outlet headers made of steel X20CrMoV121 following operation in creep conditions in time periods considerably longer than the specified calculated time of operation. Strength properties, impact strength and transition temperature into brittle condition, as well as structure condition have been evaluated. On the basis of shortened creep tests, the residual life and disposable residual life of materials and welded joints have been determined. Material properties following operation and those of fabricated circumferential welded repair joints have been compared. The condition of examined components and suitability of the fabricated welded repair joints for further operation have been assessed. (orig.)

Operant conditioning of facial displays of pain.

Science.gov (United States)

Kunz, Miriam; Rainville, Pierre; Lautenbacher, Stefan

2011-06-01

The operant model of chronic pain posits that nonverbal pain behavior, such as facial expressions, is sensitive to reinforcement, but experimental evidence supporting this assumption is sparse. The aim of the present study was to investigate in a healthy population a) whether facial pain behavior can indeed be operantly conditioned using a discriminative reinforcement schedule to increase and decrease facial pain behavior and b) to what extent these changes affect pain experience indexed by self-ratings. In the experimental group (n = 29), the participants were reinforced every time that they showed pain-indicative facial behavior (up-conditioning) or a neutral expression (down-conditioning) in response to painful heat stimulation. Once facial pain behavior was successfully up- or down-conditioned, respectively (which occurred in 72% of participants), facial pain displays and self-report ratings were assessed. In addition, a control group (n = 11) was used that was yoked to the reinforcement plans of the experimental group. During the conditioning phases, reinforcement led to significant changes in facial pain behavior in the majority of the experimental group (p .136). Fine-grained analyses of facial muscle movements revealed a similar picture. Furthermore, the decline in facial pain displays (as observed during down-conditioning) strongly predicted changes in pain ratings (R(2) = 0.329). These results suggest that a) facial pain displays are sensitive to reinforcement and b) that changes in facial pain displays can affect self-report ratings.

Operational limits and conditions and operating procedures for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2005-01-01

This Safety Guide was prepared as part of the Agency's programme for establishing safety standards relating to nuclear power plants. The present Safety Guide supersedes the IAEA Safety Guide on Operational Limits and Conditions for Nuclear Power Plants which was issued in 1979 as Safety Series No. 50-SG-O3. For a nuclear power plant to be operated in a safe manner, the provisions made in the final design and subsequent modifications shall be reflected in limitations on plant operating parameters and in the requirements on plant equipment and personnel. Under the responsibility of the operating organization, these shall be developed during the design safety evaluation as a set of operational limits and conditions (OLCs). A major contribution to compliance with the OLCs is made by the development and utilization of operating procedures (OPs) that are consistent with and fully implement the OLCs. The requirements for the OLCs and OPs are established in Section 5 of the IAEA Safety Requirements publication Safety of Nuclear Power Plants: Operation, which this Safety Guide supplements. The purpose of this Safety Guide is to provide guidance on the development, content and implementation of OLCs and OPs. The Safety Guide is directed at both regulators and owners/operators. This Safety Guide covers the concept of OLCs, their content as applicable to land based stationary power plants with thermal neutron reactors, and the responsibilities of the operating organization regarding their establishment, modification, compliance and documentation. The OPs to support the implementation of the OLCs and to ensure their observance are also within the scope of this Safety Guide. The particular aspects of the procedures for maintenance, surveillance, in-service inspection and other safety related activities in connection with the safe operation of nuclear power plants are outside the scope of this Safety Guide but can be found in other IAEA Safety Guides. Section 2 indicates the

Operational limits and conditions and operating procedures for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2000-01-01

This Safety Guide was prepared as part of the Agency's programme for establishing safety standards relating to nuclear power plants. The present Safety Guide supersedes the IAEA Safety Guide on Operational Limits and Conditions for Nuclear Power Plants which was issued in 1979 as Safety Series No. 50-SG-O3. For a nuclear power plant to be operated in a safe manner, the provisions made in the final design and subsequent modifications shall be reflected in limitations on plant operating parameters and in the requirements on plant equipment and personnel. Under the responsibility of the operating organization, these shall be developed during the design safety evaluation as a set of operational limits and conditions (OLCs). A major contribution to compliance with the OLCs is made by the development and utilization of operating procedures (OPs) that are consistent with and fully implement the OLCs. The requirements for the OLCs and OPs are established in Section 5 of the IAEA Safety Requirements publication Safety of Nuclear Power Plants: Operation, which this Safety Guide supplements. The purpose of this Safety Guide is to provide guidance on the development, content and implementation of OLCs and OPs. The Safety Guide is directed at both regulators and owners/operators. This Safety Guide covers the concept of OLCs, their content as applicable to land based stationary power plants with thermal neutron reactors, and the responsibilities of the operating organization regarding their establishment, modification, compliance and documentation. The OPs to support the implementation of the OLCs and to ensure their observance are also within the scope of this Safety Guide. The particular aspects of the procedures for maintenance, surveillance, in-service inspection and other safety related activities in connection with the safe operation of nuclear power plants are outside the scope of this Safety Guide but can be found in other IAEA Safety Guides. Section 2 indicates the

Operating conditions of batteries in off-grid renewable energy systems

DEFF Research Database (Denmark)

Svoboda, V.; Wenzl, H.; Kaiser, R.

2007-01-01

for batteries. Categories are defined in such a way that batteries belonging to the same category are subjected to similar operating conditions and a similar combination of stress factors. The results provide a comprehensive overview of battery operating conditions in existing off-grid renewable energy systems...

System and method of vehicle operating condition management

Science.gov (United States)

Sujan, Vivek A.; Vajapeyazula, Phani; Follen, Kenneth; Wu, An; Moffett, Barty L.

2015-10-20

A vehicle operating condition profile can be determined over a given route while also considering imposed constraints such as deviation from time targets, deviation from maximum governed speed limits, etc. Given current vehicle speed, engine state and transmission state, the present disclosure optimally manages the engine map and transmission to provide a recommended vehicle operating condition that optimizes fuel consumption in transitioning from one vehicle state to a target state. Exemplary embodiments provide for offline and online optimizations relative to fuel consumption. The benefit is increased freight efficiency in transporting cargo from source to destination by minimizing fuel consumption and maintaining drivability.

Controllable conditional quantum oscillations and quantum gate operations in superconducting flux qubits

International Nuclear Information System (INIS)

Chen Aimin; Cho Samyoung

2011-01-01

Conditional quantum oscillations are investigated for quantum gate operations in superconducting flux qubits. We present an effective Hamiltonian which describes a conditional quantum oscillation in two-qubit systems. Rabi-type quantum oscillations are discussed in implementing conditional quantum oscillations to quantum gate operations. Two conditional quantum oscillations depending on the states of control qubit can be synchronized to perform controlled-gate operations by varying system parameters. It is shown that the conditional quantum oscillations with their frequency synchronization make it possible to operate the controlled-NOT and -U gates with a very accurate gate performance rate in interacting qubit systems. Further, this scheme can be applicable to realize a controlled multi-qubit operation in various solid-state qubit systems. (author)

Operant Conditioning in Older Adults with Alzheimer's Disease

Science.gov (United States)

Spira, Adam P.; Edelstein, Barry A.

2007-01-01

Behavioral interventions based on operant principles are commonly attempted to manage agitation in older adults with dementia. The extent to which operant conditioning can occur in persons with particular dementias, however, is unclear. The present study involved use of a button-pressing task to evaluate the sensitivity of the responding of older…

Limits and conditions for permanent operation of the LVR-15 reactor

International Nuclear Information System (INIS)

1995-03-01

The ''Limits and Conditions'' have been set up to demonstrate compliance with all nuclear safety requirements specified by the Decree of the Czechoslovak Atomic Energy Commission No. 9/1985, and to serve as a guide for the reactor operators to respond adequately to deviations from the required values in normal operation conditions. The publications is divided into the following chapters: (1) Safety limits of the LVR-15 reactor; (2) Adjusting the reactor protection and control system parameters; (3) Limiting conditions for normal operation modes; (4) Control requirements; and (5) reactor operation management. A document by the Institute for Research, Production, and Application of Radioisotopes specifying conditions for the acceptance of radioactive wastes to the central repository is appended. (P.A.). 7 tabs

Effects of exercise conditioning on thermoregulatory responses to repeated administration of chlorpyrifos

International Nuclear Information System (INIS)

Rowsey, Pamela Johnson; Metzger, Bonnie L.; Arlson, John; Gordon, Christopher J.

2003-01-01

little is known about the effects of physical activity (i.e., exercise training) on susceptibility to environmental toxicants. Chloropyrifos (CHP), an organophosphate (OP) insecticide, affects thermoregulation, causing a cute period of hypothermia followed by a delayed fever. Since exercise conditioning alters the thermo regulatory responses of rodents, this study examined whether exercise training would alter the thermo regulatory response to repeated CHP administration in the female Sprague-Dawley rat. Core temperature (T c ) and motor activity (MA) were monitored by radio telemetry in rats housed at an ambient temperature (T a ) of 22 deg. C. The rats either were provided with continuous access to running wheels (exercise group) or were housed in standard cages without wheels (sedentary group). The exercise group rats ran predominately at night with an average of 7.6 km/24 h. After 8 weeks the rats in both groups were garaged daily with corn oil or 10 mg/kg HP (dissolved in corn oil) for 4 days. CHP induced an immediate hypothermic response followed by a delayed fever throughout the next day in the sedentary group rats after the first three doses of CHP. The exercise group rats showed no hypothermia after the first dose of CHP. However, they became hypothermic after the second and third doses of CHP. The exercise group rats developed a smaller daytime fever after each dose of CHP compared to the sedentary group rats. Overall, exercise training attenuated the hypothermic and febrile effects of repeated CHP. Thus, the data suggest that a sedentary lifestyle may increase the sensitivity to OP insecticides. Exercise training was also associated with a more rapid recovery of plasma cholinesterase activity

Automated Operant Conditioning in the Mouse Home Cage.

Science.gov (United States)

Francis, Nikolas A; Kanold, Patrick O

2017-01-01

Recent advances in neuroimaging and genetics have made mice an advantageous animal model for studying the neurophysiology of sensation, cognition, and locomotion. A key benefit of mice is that they provide a large population of test subjects for behavioral screening. Reflex-based assays of hearing in mice, such as the widely used acoustic startle response, are less accurate than operant conditioning in measuring auditory processing. To date, however, there are few cost-effective options for scalable operant conditioning systems. Here, we describe a new system for automated operant conditioning, the Psibox. It is assembled from low cost parts, designed to fit within typical commercial wire-top cages, and allows large numbers of mice to train independently in their home cages on positive reinforcement tasks. We found that groups of mice trained together learned to accurately detect sounds within 2 weeks of training. In addition, individual mice isolated from groups also showed good task performance. The Psibox facilitates high-throughput testing of sensory, motor, and cognitive skills in mice, and provides a readily available animal population for studies ranging from experience-dependent neural plasticity to rodent models of mental disorders.

Repeatability, Reproducibility and Standardisation of a Laser Doppler Imaging Technique for the Evaluation of Normal Mouse Hindlimb Perfusion

Directory of Open Access Journals (Sweden)

Arturo Brunetti

2012-12-01

Full Text Available Background. Preclinical perfusion studies are useful for the improvement of diagnosis and therapy in dermatologic, cardiovascular and rheumatic human diseases. The Laser Doppler Perfusion Imaging (LDPI technique has been used to evaluate superficial alterations of the skin microcirculation in surgically induced murine hindlimb ischemia. We assessed the reproducibility and the accuracy of LDPI acquisitions and identified several critical factors that could affect LDPI measurements in mice. Methods. Twenty mice were analysed. Statistical standardisation and a repeatability and reproducibility analysis were performed on mouse perfusion signals with respect to differences in body temperature, the presence or absence of hair, the type of anaesthesia used for LDPI measurements and the position of the mouse body. Results. We found excellent correlations among measurements made by the same operator (i.e., repeatability under the same experimental conditions and by two different operators (i.e., reproducibility. A Bland-Altman analysis showed the absence of bias in repeatability (p = 0.29 or reproducibility (p = 0.89. The limits of agreement for repeatability were –0.357 and –0.033, and for reproducibility, they were –0.270 and 0.238. Significant differences in perfusion values were observed in different experimental groups. Conclusions. Different experimental conditions must be considered as a starting point for the evaluation of new drugs and strategic therapies.

Flux behaviour under different operational conditions in osmosis process

DEFF Research Database (Denmark)

Korenak, Jasmina; Zarebska, Agata; Buksek, Hermina

the active membrane layer is facing draw solution. Osmosis process can be affected by several factors, such as operating conditions (temperature and cross flow velocity), feed and draw solution properties, and membrane characteristics. These factors can significantly contribute to the efficiency......, and total dissolved solids. Taken together our results can contribute understanding of the how performance of asymmetric FO membranes can be enhanced by feed and draw properties, membrane characteristics and operational conditions.......The transport of water molecules across a semi-permeable membrane is driven by the osmotic pressure difference between feed and draw solution. Two different operational modes can be distinguished, namely FO mode when the active membrane layer is facing the wastewater (feed), and PRO mode when...

Operational forecasting of human-biometeorological conditions

Science.gov (United States)

Giannaros, T. M.; Lagouvardos, K.; Kotroni, V.; Matzarakis, A.

2018-03-01

This paper presents the development of an operational forecasting service focusing on human-biometeorological conditions. The service is based on the coupling of numerical weather prediction models with an advanced human-biometeorological model. Human thermal perception and stress forecasts are issued on a daily basis for Greece, in both point and gridded format. A user-friendly presentation approach is adopted for communicating the forecasts to the public via the worldwide web. The development of the presented service highlights the feasibility of replacing standard meteorological parameters and/or indices used in operational weather forecasting activities for assessing the thermal environment. This is of particular significance for providing effective, human-biometeorology-oriented, warnings for both heat waves and cold outbreaks.

Optimal operating conditions for external cavity semiconductor laser optical chaos communication system

International Nuclear Information System (INIS)

Priyadarshi, S; Pierce, I; Hong, Y; Shore, K A

2012-01-01

In optical chaos communications a message is masked in the noise-like broadband output of a chaotic transmitter laser, and message recovery is enabled through the synchronization of the transmitter and the (chaotic) receiver laser. Key issues are to identify the laser operating conditions which provide the highest quality synchronization conditions and those which provide optimized message extraction. In general such operating conditions are not coincident. In this paper numerical simulations are performed with the aim of identifying a regime of operation where the highest quality synchronization and optimizing message extraction efficiency are achieved simultaneously. Use of such an operating regime will facilitate practical deployment of optical chaos communications systems without the need for re-adjustment of laser operating conditions in the field. (paper)

Pre-Swirl Stator and Propeller Design for Varying Operating Conditions

DEFF Research Database (Denmark)

Saettone, Simone; Regener, Pelle Bo; Andersen, Poul

2016-01-01

blades ahead of the propeller.This paper describes the hydrodynamic design of apre-swirl stator with radially variable pitch, paired with aconventional propeller. The aim is to achieve the highest possible effciency in various operating conditions, and to avoid effciency penalties in off-design operation.......To investigate the propeller and stator designs and configurations in different operating conditions, the computationally inexpensive vortex-lattice method is used a sa first step to optimize the geometry in an initial parameter study. Then the flow over hull, stator and propelleris simulated in a CFD...

Operating features of decorative polymer-impregnated concretes under severe operating conditions

International Nuclear Information System (INIS)

Kapustina, I.B.; Lobasenok, V.A.; Yakimtsiv, V.P.

1991-01-01

The study was carried out to investigate the possibility of a decorative polymer-impregnated concrete as a lining material in radiation-endangered rooms. Their extreme properties such as radiation resistance, decontamination ability, fire resistance and melting-freezing cycle resistance were studied. The material proposed shows substantially high resistance under severe operating conditions

Equivalent Electrical Circuits of Thermoelectric Generators under Different Operating Conditions

Directory of Open Access Journals (Sweden)

Saima Siouane

2017-03-01

Full Text Available Energy harvesting has become a promising and alternative solution to conventional energy generation patterns to overcome the problem of supplying autonomous electrical systems. More particularly, thermal energy harvesting technologies have drawn a major interest in both research and industry. Thermoelectric Generators (TEGs can be used in two different operating conditions, under constant temperature gradient or constant heat flow. The commonly used TEG electrical model, based on a voltage source in series with an electrical resistance, shows its limitations especially under constant heat flow conditions. Here, the analytical electrical modeling, taking into consideration the internal and contact thermal resistances of a TEG under constant temperature gradient and constant heat flow conditions, is first given. To give further insight into the electrical behavior of a TEG module in different operating conditions, we propose a new and original way of emulating the above analytical expressions with usual electronics components (voltage source, resistors, diode, whose values are determined with the TEG’s parameters. Note that such a TEG emulation is particularly suited when designing the electronic circuitry commonly associated to the TEG, to realize both Maximum Power Point Tracking and output voltage regulation. First, the proposed equivalent electrical circuits are validated through simulation with a SPICE environment in static operating conditions using only one value of either temperature gradient or heat flow. Then, they are also analyzed in dynamic operating conditions where both temperature gradient and heat flow are considered as time-varying functions.

Experimental study on the impact of operating conditions on PCCI combustion

NARCIS (Netherlands)

Leermakers, C.A.J.; Luijten, C.C.M.; Somers, L.M.T.; Goey, de L.P.H.; Albrecht, B.A.

2013-01-01

In a short–term scenario, using near–standard components and conventional fuels, PCCI combustion relies on a smart choice of operating conditions. Here, the effects of operating conditions on ignition delay, available mixing time, combustion phasing and emissions are investigated. In the PCCI

Geometrical conditions for completely positive trace-preserving maps and their application to a quantum repeater and a state-dependent quantum cloning machine

International Nuclear Information System (INIS)

Carlini, A.; Sasaki, M.

2003-01-01

We address the problem of finding optimal CPTP (completely positive trace-preserving) maps between a set of binary pure states and another set of binary generic mixed state in a two-dimensional space. The necessary and sufficient conditions for the existence of such CPTP maps can be discussed within a simple geometrical picture. We exploit this analysis to show the existence of an optimal quantum repeater which is superior to the known repeating strategies for a set of coherent states sent through a lossy quantum channel. We also show that the geometrical formulation of the CPTP mapping conditions can be a simpler method to derive a state-dependent quantum (anti) cloning machine than the study so far based on the explicit solution of several constraints imposed by unitarity in an extended Hilbert space

Solid oxide fuel cell performance under severe operating conditions

DEFF Research Database (Denmark)

Koch, Søren; Hendriksen, P.V.; Mogensen, Mogens Bjerg

2006-01-01

The performance and degradation of Solid Oxide Fuel Cells (SOFC) were studied under severe operating conditions. The cells studied were manufactured in a small series by ECN, in the framework of the EU funded CORE-SOFC project. The cells were of the anode-supported type with a double layer LSM...... cathode. They were operated at 750 °C or 850 °C in hydrogen with 5% or 50% water at current densities ranging from 0.25 A cm–2 to 1 A cm–2 for periods of 300 hours or more. The area specific cell resistance, corrected for fuel utilisation, ranged between 0.20 Ω cm2 and 0.34 Ω cm2 at 850 °C and 520 m......V, and between 0.51 Ω cm2 and 0.92 Ω cm2 at 750 °C and 520 mV. The degradation of cell performance was found to be low (ranging from 0 to 8%/1,000 hours) at regular operating conditions. Voltage degradation rates of 20 to 40%/1,000 hours were observed under severe operating conditions, depending on the test...

Operant Conditioning: A Tool for Special Physical Educators in the 1980s.

Science.gov (United States)

Dunn, John M.; French, Ron

1982-01-01

The usefulness of operant conditioning for the special physical educator in managing behavior problems is pointed out, and steps to follow in applying operant conditioning techniques are outlined. (SB)

Pain Report and Pain-Related Evoked Potentials Operantly Conditioned

NARCIS (Netherlands)

Lousberg, Richel; Vuurman, Eric; Lamers, Theo; van Breukelen, Gerard; Jongen, Ellen; Rijnen, Heidi; Maessen, Christa; Hermens, Hermanus J.

Objective: The purpose of the present study was to answer the ques- tion whether pain report can be increased and decreased by operant conditioning. We predicted that the conditioned pain effects would remain significant after correction for social desirability and fantasy proneness. Furthermore, we

The Operator's Diagnosis Task under Abnormal Operating Conditions in Industrial Process Plant

DEFF Research Database (Denmark)

Goodstein, L.P.; Pedersen, O.M.; Rasmussen, Jens

1974-01-01

Analysis of serious accidents in connection with the operation of technical installations demonstrate that the diagnosis task which confronts personnel under non-normal plant conditions is a critical one. This report presents a preliminary outline of characteristic traits connected with the task...... of diagnosis for use in discussions of (a) the studies which are necessary in order to formulate the operator's diagnostic procedures and (b) the possibilities which exists for supporting these procedures through appropriate data processing and display in the control system. At the same time, attempts are made...

Operant Conditioning and Learning: Examples, Sources, Technology.

Science.gov (United States)

Pedrini, Bonnie C.; Pedrini, D. T.

The purpose of this paper is to relate psychology to teaching generally, and to relate behavior shaping to curriculum, specifically. Focusing on operant conditioning and learning, many studies are cited which illustrate some of the work being done toward effectively shaping or modifying student behavior whether in terms of subject matter or…

Analysis of repeated measures data

CERN Document Server

Islam, M Ataharul

2017-01-01

This book presents a broad range of statistical techniques to address emerging needs in the field of repeated measures. It also provides a comprehensive overview of extensions of generalized linear models for the bivariate exponential family of distributions, which represent a new development in analysing repeated measures data. The demand for statistical models for correlated outcomes has grown rapidly recently, mainly due to presence of two types of underlying associations: associations between outcomes, and associations between explanatory variables and outcomes. The book systematically addresses key problems arising in the modelling of repeated measures data, bearing in mind those factors that play a major role in estimating the underlying relationships between covariates and outcome variables for correlated outcome data. In addition, it presents new approaches to addressing current challenges in the field of repeated measures and models based on conditional and joint probabilities. Markov models of first...

Lifting simulation of an offshore supply vessel considering various operating conditions

Directory of Open Access Journals (Sweden)

Dong-Hoon Jeong

2016-06-01

Full Text Available Recently, an offshore support vessel is being widely used to install an offshore structure such as a subsea equipment which is laid on its deck. The lifting operation which is one of the installation operations includes lifting off, lifting in the air, splash zone crossing, deep submerging, and finally landing of the structure with an offshore support vessel crane. There are some major considerations during this operation. Especially, when lifting off the structure, if operating conditions such as ocean environmental loads and hoisting (or lowering speed are bad, the excess of tension of wire ropes of the crane and the collision between the offshore support vessel and the structure can be occurred due to the relative motion between them. To solve this problem, this study performs the lifting simulation while the offshore support vessel installs the structure. The simulation includes the calculation of dynamic responses of the offshore support vessel and the equipment, including the wire tension and the collision detection. To check the applicability of the simulation, it is applied to some lifting steps by varying operating conditions. As a result, it is confirmed that the conditions affect the operability of those steps.

Limiting conditions for operation relaxation program

International Nuclear Information System (INIS)

Merz, J.F.

1985-01-01

The purpose of this effort was to assess the impact of system maintenance unavailability on plant risk to provide technical justification for the relaxation of system limiting conditions for operation from three to seven days. The primary goal of the relaxation program is to allow for more thorough equipment maintenance. A potential increase in out-of-service time for a particular outage caused by the performance of more effective repairs will be counterbalanced by a probable decrease in the frequency in the outage rate of a component. Benefits resulting from an increase in allowed outage time include: (a) a potential reduction in total system out-of-service time, (b) a minimization of challenges to plant systems, and (c) a reduction in the number of emergency technical specification change requests. This program therefore offers an opportunity to more effectively manage plant maintenance and operation

Analysis of operating conditions of the voltage transformer

Directory of Open Access Journals (Sweden)

Fastiy G. P.

2017-12-01

Full Text Available In electrical networks, constant monitoring of the electrical equipment operation is necessary. To accomplish this task, current transformers and voltage transformers (VT are used, on which the accuracy of electrical measurements, electricity metering, and the reliability of the emergency control system depend. The results of the analysis of the conditions for forming the magnetization of a voltage transformer in the mode with unilateral connection of overhead transmission lines, as well as variants of violations in the 110 kV network that may exist for a relatively long time have been presented. It should be noted that the considered network has its own peculiarities: the overhead transmission lines connected in series have a significant length and a low level of load, which may be a condition for the appearance of a transmission lines capacitive effect (the Ferranti effect, the latter can cause overvoltage. Overvoltage occurs when the operating modes are temporary in terms of operation, adverse combinations of network parameters take place, and can continue until the circuit and network modes change. Most often they appear in asymmetric modes, with short circuits to ground, etc. Asymmetric modes caused by incomplete-phase commutations and wire breaks on the overhead line, as well as wire breaks with subsequent disconnection of power transformers that can affect the voltage level on the VT have been considered. The possibility of VT magnetizing with a prolonged voltage rise in symmetric modes, namely, the manifestation of the Ferranti effect with various loads at substations up to complete switching-off and power transformers switching off has been investigated. The analysis of the measuring voltage transformer operating conditions has been based on materials provided by the "Kolenergo" services.

Analysis of Fukushima unit 2 accident considering the operating conditions of RCIC system

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Il, E-mail: sikim@kaeri.re.kr; Park, Jong Hwa; Ha, Kwang Soon; Cho, Song-Won; Song, JinHo

2016-03-15

Highlights: • Fukushima unit 2 accident was analyzed using MELCOR 1.8.6. • RCIC operating conditions were assumed and best case was selected. • Effect of RCIC operating condition on accident scenario was found. - Abstract: A severe accident in Fukushima occurred on March 11, 2011 and units 1, 2 and 3 were damaged severely. A tsunami following an earthquake made the supply of electricity power stop, and the safety systems, which use AC or DC power in plants could not operate properly. It is supposed that the degree of core degradation of unit 2 is less serious than in the other plants, and it was estimated that the operation of reactor core isolation cooling (RCIC) system at the initial stage of the accident minimized the core damage through decay heat removal. Although the operating conditions of the RCIC system are not known clearly, it can be important to analyze the accident scenario of unit 2. In this study, best case of the Fukushima unit 2 accident was presented considering the operating conditions of the RCIC system. The effects of operating condition on core degradation and fission product release rate to environment were also examined. In addition, importance of torus room flooding level in the accident analysis was discussed. MELCOR 1.8.6 was used in this research, and the geometries of plant and operating conditions of safety system were obtained from TEPCO through OECD/NEA BSAF Project.

Assessment of biogas production from MBT waste under different operating conditions

DEFF Research Database (Denmark)

Pantini, Sara; Verginelli, Jason; Lombardi, Francesco

2015-01-01

In this work, the influence of different operating conditions on the biogas production from mechanically-. biologically treated (MBT) wastes is investigated. Specifically, different lab-scale anaerobic tests varying the water content (26-43% w/w up to 75% w/w), the temperature (from 20 to 25......, the obtained results highlighted that the operative conditions can drastically affect the gas production from MET wastes. This suggests that particular caution should be paid when using the results of lab-scale tests for the evaluation of long-term behaviour expected in the field where the boundary conditions...

A Problem-Solving Approach to Teaching Operant Conditioning

Science.gov (United States)

Shields, Carolyn; Gredler, Margaret

2003-01-01

Psychology students frequently have misconceptions of basic concepts in operant conditioning. Prior classroom observations revealed that most students defined positive reinforcement as reward and equated negative reinforcement and punishment. Students also labeled positive reinforcement as rewarding good behavior and negative reinforcement as…

Schwarzian conditions for linear differential operators with selected differential Galois groups

International Nuclear Information System (INIS)

Abdelaziz, Y; Maillard, J-M

2017-01-01

We show that non-linear Schwarzian differential equations emerging from covariance symmetry conditions imposed on linear differential operators with hypergeometric function solutions can be generalized to arbitrary order linear differential operators with polynomial coefficients having selected differential Galois groups. For order three and order four linear differential operators we show that this pullback invariance up to conjugation eventually reduces to symmetric powers of an underlying order-two operator. We give, precisely, the conditions to have modular correspondences solutions for such Schwarzian differential equations, which was an open question in a previous paper. We analyze in detail a pullbacked hypergeometric example generalizing modular forms, that ushers a pullback invariance up to operator homomorphisms. We finally consider the more general problem of the equivalence of two different order-four linear differential Calabi–Yau operators up to pullbacks and conjugation, and clarify the cases where they have the same Yukawa couplings. (paper)

Schwarzian conditions for linear differential operators with selected differential Galois groups

Science.gov (United States)

Abdelaziz, Y.; Maillard, J.-M.

2017-11-01

We show that non-linear Schwarzian differential equations emerging from covariance symmetry conditions imposed on linear differential operators with hypergeometric function solutions can be generalized to arbitrary order linear differential operators with polynomial coefficients having selected differential Galois groups. For order three and order four linear differential operators we show that this pullback invariance up to conjugation eventually reduces to symmetric powers of an underlying order-two operator. We give, precisely, the conditions to have modular correspondences solutions for such Schwarzian differential equations, which was an open question in a previous paper. We analyze in detail a pullbacked hypergeometric example generalizing modular forms, that ushers a pullback invariance up to operator homomorphisms. We finally consider the more general problem of the equivalence of two different order-four linear differential Calabi-Yau operators up to pullbacks and conjugation, and clarify the cases where they have the same Yukawa couplings.

Evaluation of turbine microjet engine operating parameters in conditions conducive to inlet freezing

Directory of Open Access Journals (Sweden)

Markowski Jaroslaw

2017-01-01

Full Text Available The problem of turbine microjet engine operation is related to flight conditions of unmanned aircraft. These flights are often performed at low altitudes, where, in autumn and winter conditions, the air can be characterized by high humidity and low temperature. Such operating conditions may cause freezing the turbine engine inlet. In particular, this problem may be related to microengines, which most often are not equipped with a de-icing installation. Frosting of the inlet violates the air flow conditions at the engine inlet and may cause unstable operation and even outages, which eventually may lead to a loss of aircraft’s stability and breakdown. Therefore, an attempt was made to evaluate the changes in operational parameters of the turbine microjet engine under conditions leading to the freezing of the inlet. The engine test was performed in stationary conditions and the analysis of the obtained results are presented in this article.

Effect of RCIC Operating Conditions on the Accident Scenario in Fukushima Unit 2

International Nuclear Information System (INIS)

Kim, Sung Il; Park, Jong Hwa; Ha, Kwang Soon

2015-01-01

This study was conducted by using MELCOR 1.8.6. Fukushima unit 2 accident was analyzed using MELCOR in this study, and best estimate scenario with considering RCIC operating conditions was presented. Researches on the boiling water reactor (BWR) plant with reactor core isolation cooling (RCIC) system have been conducted. Research on the RCIC operation in Fukushima unit 2 was also conducted by Sandia National Laboratory. MELCOR analysis of the Fukushima unit 2 accident was conducted in the report and energy balance in wetwell was described by considering RCIC operation. However, the effect of RCIC operation condition on the accident scenario has not been studied. The operating conditions of RCIC system affect the pressures in wetwell and drywell, and the high pressure can make leakage path of fission product from PCV to reactor building. Thus it can be directly related with the amount of fission product which released to environment. In this study, severe accident on Fukushima unit 2 was analyzed considering the operating condition of RCIC system, and best estimated scenario was presented. In addition, the effect of RCIC turbine efficiency on the accident progression was examined. Energy balance in suppression chamber was also considered with discussion on the effect of torus room flooding level. It was found that the operating condition of RCIC turbine not only affects the variation of drywell pressure but also the amount of released fission products to environment. It was also confirmed that the RCIC turbine efficiency in the accident would be less than normal operating condition

Model Skinner Operant Conditioning automata i bionički naučeno upravljanje robota

OpenAIRE

Cai, Jianxian; Hong, Li; Cheng, Lina; Yu, Ruihong

2016-01-01

Fuzzy Skinner Operant Conditioning Automaton (FSOCA) sastavljen je na temelju Operant Conditioning mehanizma primjenom teorije neizrazitih skupova. Osnovno obilježje automata FSOCA je sljedeće: neizraziti rezultati stanja pomoću Gausove funkcije koriste se kao skupovi neizrazitog stanja; neizrazita pravila preslikavanja (fuzzy mapping rules) kod fuzzy-conditioning-operacije zamjenjuju stohastičke "conditioning-operant" skupove preslikavanja. Stoga se automat FSOCA može koristiti za opisivanje...

30 CFR 250.522 - When do I have to repeat casing diagnostic testing?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to repeat casing diagnostic... Operations Casing Pressure Management § 250.522 When do I have to repeat casing diagnostic testing? Casing diagnostic testing must be repeated according to the following table: When * * * you must repeat diagnostic...

Self-adjoint elliptic operators with boundary conditions on not closed hypersurfaces

Science.gov (United States)

Mantile, Andrea; Posilicano, Andrea; Sini, Mourad

2016-07-01

The theory of self-adjoint extensions of symmetric operators is used to construct self-adjoint realizations of a second-order elliptic differential operator on Rn with linear boundary conditions on (a relatively open part of) a compact hypersurface. Our approach allows to obtain Kreĭn-like resolvent formulae where the reference operator coincides with the ;free; operator with domain H2 (Rn); this provides an useful tool for the scattering problem from a hypersurface. Concrete examples of this construction are developed in connection with the standard boundary conditions, Dirichlet, Neumann, Robin, δ and δ‧-type, assigned either on a (n - 1) dimensional compact boundary Γ = ∂ Ω or on a relatively open part Σ ⊂ Γ. Schatten-von Neumann estimates for the difference of the powers of resolvents of the free and the perturbed operators are also proven; these give existence and completeness of the wave operators of the associated scattering systems.

Operant Conditioning Concepts in Introductory Psychology Textbooks and Their Companion Web Sites

Science.gov (United States)

Sheldon, Jane P.

2002-01-01

Psychology instructors and textbook authors rate operant conditioning as one of the most essential concepts for students to learn, yet textbook writers, as well as students, can fall prey to misconceptions. This study is a content analysis of the presentation of operant conditioning in introductory psychology textbooks and their companion Web…

Mathematical modelling of unglazed solar collectors under extreme operating conditions

DEFF Research Database (Denmark)

Bunea, M.; Perers, Bengt; Eicher, S.

2015-01-01

average temperature levels at the evaporator. Simulation of these systems requires a collector model that can take into account operation at very low temperatures (below freezing) and under various weather conditions, particularly operation without solar irradiation.A solar collector mathematical model......Combined heat pumps and solar collectors got a renewed interest on the heating system market worldwide. Connected to the heat pump evaporator, unglazed solar collectors can considerably increase their efficiency, but they also raise the coefficient of performance of the heat pump with higher...... was found due to the condensation phenomenon and up to 40% due to frost under no solar irradiation. This work also points out the influence of the operating conditions on the collector's characteristics.Based on experiments carried out at a test facility, every heat flux on the absorber was separately...

14 CFR 203.5 - Compliance as condition on operations in air transportation.

Science.gov (United States)

2010-01-01

... air transportation. 203.5 Section 203.5 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... DEFENSES § 203.5 Compliance as condition on operations in air transportation. It shall be a condition on the authority of all direct U.S. and foreign carriers to operate in air transportation that they have...

Keeping the secret: Insights from repeated catchment-scale tracer experiments under transient conditions

Science.gov (United States)

Bogner, Christina; Hauhs, Michael; Lange, Holger

2016-04-01

Catchment-level tracer experiments are generally performed to identify site-specific hydrological response functions of the catchment. The existence and uniqueness of these response functions are hardly ever questioned. Here, we report on a series of replicated tracer experiments in two small first-order catchments, G1 (0.6 ha, roofed) and F4 (2.3 ha, without roof) at Gårdsjön in SW Sweden. The soils in both catchments are shallow (500 m2) the experiments were done without a roof mostly at transient conditions. The catchment F4 was equipped with a sprinkler system with a watering capacity of around 38-45 m3 day-1. Natural rainfall comes in addition. A bromide tracer solution was injected to groundwater at a single location about 40 m upstream the weir over a period of less than an hour, and was monitored using a set of groundwater tubes and the weir at the outlet over the following 4 days. In addition, discharge was measured. The experiments were repeated each summer from 2007 to 2015. While steady state conditions were guaranteed in G1, steady runoff has been achieved only four times in F4. We investigated tracer recovery rates against cumulated runoff since tracer application. Substantially different transit times and qualitatively different behaviour of the breakthrough curves were observed, even under steady state conditions. In G1, no single system response function could be identified in 5 replicates. Similarly, the catchment response functions in F4 under steady state differed between experiments. However, they remained in a similar range as in G1. Based on these results, we question the identifiability of flow paths and system properties, such as saturated water content or hydrologic transmissivity, at the catchment scale using tracer experiments. Rather, the series demonstrate the utter importance of the initial and boundary conditions which largely determine the response of the system to inert tracer pulses.

EFFECT OF PRE-COOLING ON REPEAT-SPRINT PERFORMANCE IN SEASONALLY ACCLIMATISED MALES DURING AN OUTDOOR SIMULATED TEAM-SPORT PROTOCOL IN WARM CONDITIONS

Directory of Open Access Journals (Sweden)

Carly J. Brade

2013-09-01

Full Text Available Whether precooling is beneficial for exercise performance in warm climates when heat acclimatised is unclear. The purpose of this study was to determine the effect of precooling on repeat-sprint performance during a simulated team-sport circuit performed outdoors in warm, dry field conditions in seasonally acclimatised males (n = 10. They performed two trials, one with precooling (PC; ice slushy and cooling jacket and another without (CONT. Trials began with a 30-min baseline/cooling period followed by an 80 min repeat-sprint protocol, comprising 4 x 20-min quarters, with 2 x 5-min quarter breaks and a 10-min half-time recovery/cooling period. A clear and substantial (negative; PC slower effect was recorded for first quarter circuit time. Clear and trivial effects were recorded for overall circuit time, third and fourth quarter sprint times and fourth quarter best sprint time, otherwise unclear and trivial effects were recorded for remaining performance variables. Core temperature was moderately lower (Cohen's d=0.67; 90% CL=-1.27, 0.23 in PC at the end of the precooling period and quarter 1. No differences were found for mean skin temperature, heart rate, thermal sensation, or rating of perceived exertion, however, moderate Cohen's d effect sizes suggested a greater sweat loss in PC compared with CONT. In conclusion, repeat- sprint performance was neither clearly nor substantially improved in seasonally acclimatised players by using a combination of internal and external cooling methods prior to and during exercise performed in the field in warm, dry conditions. Of practical importance, precooling appears unnecessary for repeat-sprint performance if athletes are seasonally acclimatised or artificially acclimated to heat, as it provides no additional benefit

Fuel conditioning facility electrorefiner cadmium vapor trap operation

International Nuclear Information System (INIS)

Vaden, D. E.

1998-01-01

Processing sodium-bonded spent nuclear fuel at the Fuel Conditioning Facility at Argonne National Laboratory-West involves an electrometallurgical process employing a molten LiCl-KCl salt covering a pool of molten cadmium. Previous research has shown that the cadmium dissolves in the salt as a gas, diffuses through the salt layer and vaporizes at the salt surface. This cadmium vapor condenses on cool surfaces, causing equipment operation and handling problems. Using a cadmium vapor trap to condense the cadmium vapors and reflux them back to the electrorefiner has mitigated equipment problems and improved electrorefiner operations

Effect of circadian phase on memory acquisition and recall: operant conditioning vs. classical conditioning.

Science.gov (United States)

Garren, Madeleine V; Sexauer, Stephen B; Page, Terry L

2013-01-01

There have been several studies on the role of circadian clocks in the regulation of associative learning and memory processes in both vertebrate and invertebrate species. The results have been quite variable and at present it is unclear to what extent the variability observed reflects species differences or differences in methodology. Previous results have shown that following differential classical conditioning in the cockroach, Rhyparobia maderae, in an olfactory discrimination task, formation of the short-term and long-term memory is under strict circadian control. In contrast, there appeared to be no circadian regulation of the ability to recall established memories. In the present study, we show that following operant conditioning of the same species in a very similar olfactory discrimination task, there is no impact of the circadian system on either short-term or long-term memory formation. On the other hand, ability to recall established memories is strongly tied to the circadian phase of training. On the basis of these data and those previously reported for phylogenetically diverse species, it is suggested that there may be fundamental differences in the way the circadian system regulates learning and memory in classical and operant conditioning.

Effect of circadian phase on memory acquisition and recall: operant conditioning vs. classical conditioning.

Directory of Open Access Journals (Sweden)

Madeleine V Garren

Full Text Available There have been several studies on the role of circadian clocks in the regulation of associative learning and memory processes in both vertebrate and invertebrate species. The results have been quite variable and at present it is unclear to what extent the variability observed reflects species differences or differences in methodology. Previous results have shown that following differential classical conditioning in the cockroach, Rhyparobia maderae, in an olfactory discrimination task, formation of the short-term and long-term memory is under strict circadian control. In contrast, there appeared to be no circadian regulation of the ability to recall established memories. In the present study, we show that following operant conditioning of the same species in a very similar olfactory discrimination task, there is no impact of the circadian system on either short-term or long-term memory formation. On the other hand, ability to recall established memories is strongly tied to the circadian phase of training. On the basis of these data and those previously reported for phylogenetically diverse species, it is suggested that there may be fundamental differences in the way the circadian system regulates learning and memory in classical and operant conditioning.

Development of Power Supply Management Module for Radio Signal Repeaters of Automatic Metering Reading System in Variable Solar Density Conditions

Directory of Open Access Journals (Sweden)

Kondratjevs K.

2016-02-01

Full Text Available In recent years, there has been significant research focus that revolves around harvesting and minimising energy consumption by wireless sensor network nodes. When a sensor node is depleted of energy, it becomes unresponsive and disconnected from the network that can significantly influence the performance of the whole network. The purpose of the present research is to create a power supply management module in order to provide stable operating voltage for autonomous operations of radio signal repeaters, sensors or gateways of WSN. The developed management module is composed of a solar panel, lithium battery and power supply management module. The novelty of the research is the management module, which ensures stable and uninterrupted operations of electronic equipment in various power supply modes in different situations, simultaneously ensuring energy protection and sustainability of the module components. The management module is able to provide power supply of 5 V for electronics scheme independently, without power interruption switching between power sources and power flows in different directions.

Development of Power Supply Management Module for Radio Signal Repeaters of Automatic Metering Reading System in Variable Solar Density Conditions

Science.gov (United States)

Kondratjevs, K.; Zabasta, A.; Selmanovs-Pless, V.

2016-02-01

In recent years, there has been significant research focus that revolves around harvesting and minimising energy consumption by wireless sensor network nodes. When a sensor node is depleted of energy, it becomes unresponsive and disconnected from the network that can significantly influence the performance of the whole network. The purpose of the present research is to create a power supply management module in order to provide stable operating voltage for autonomous operations of radio signal repeaters, sensors or gateways of WSN. The developed management module is composed of a solar panel, lithium battery and power supply management module. The novelty of the research is the management module, which ensures stable and uninterrupted operations of electronic equipment in various power supply modes in different situations, simultaneously ensuring energy protection and sustainability of the module components. The management module is able to provide power supply of 5 V for electronics scheme independently, without power interruption switching between power sources and power flows in different directions.

Repeated adjacent-segment degeneration after posterior lumbar interbody fusion.

Science.gov (United States)

Okuda, Shinya; Oda, Takenori; Yamasaki, Ryoji; Maeno, Takafumi; Iwasaki, Motoki

2014-05-01

One of the most important sequelae affecting long-term results is adjacent-segment degeneration (ASD) after posterior lumbar interbody fusion (PLIF). Although several reports have described the incidence rate, there have been no reports of repeated ASD. The purpose of this report was to describe 1 case of repeated ASD after PLIF. A 62-year-old woman with L-4 degenerative spondylolisthesis underwent PLIF at L4-5. At the second operation, L3-4 PLIF was performed for L-3 degenerative spondylolisthesis 6 years after the primary operation. At the third operation, L2-3 PLIF was performed for L-2 degenerative spondylolisthesis 1.5 years after the primary operation. Vertebral collapse of L-1 was detected 1 year after the third operation, and the collapse had progressed. At the fourth operation, 3 years after the third operation, vertebral column resection of L-1 and replacement of titanium mesh cages with pedicle screw fixation between T-4 and L-5 was performed. Although the patient's symptoms resolved after each operation, the time between surgeries shortened. The sacral slope decreased gradually although each PLIF achieved local lordosis at the fused segment.

14 CFR 125.221 - Icing conditions: Operating limitations.

Science.gov (United States)

2010-01-01

... appendix C of this part or those for transport category airplane type certification, no pilot may fly— (1... pilot may fly an airplane into known or forecast severe icing conditions. (e) If current weather reports... CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD...

Updating Coverage of Operant Conditioning in Introductory Psychology.

Science.gov (United States)

Buskist, William; Miller, Erin; Ecott, Cheryl; Critchfield, Thomas S.

1999-01-01

Offers an example of determining what the experts of psychology deem as essential concepts in their subfield by investigating the current principles in operant conditioning through surveys of the board of editors of the "Journal of the Experimental Analysis of Behavior." Recommends concepts that are appropriate for up-to-date coverage of operant…

Effects of Operating Conditions on Gas Release Thermal ...

African Journals Online (AJOL)

The gas release rates and the flame length of the potential jet fires were initially estimated using Simplex Source Term Models which pay limited attention to operating conditions. Finally a more detailed follow-up study, accounting for a range of practical factors was conducted. A number of useful risk management metrics ...

Sex differences in learning processes of classical and operant conditioning.

Science.gov (United States)

Dalla, Christina; Shors, Tracey J

2009-05-25

Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear-conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear-conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion, males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent in one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them.

Design and operating condition. Consequences for EDF NPP's chemistry

International Nuclear Information System (INIS)

Bretelle, Jean-Luc; Stutzmann, Agnes; Nordmann, Francis

2009-01-01

Since the beginning of the French nuclear programme in 1977, four major types of design have been commissioned, the fifth one being under construction (EPR). The paper points out advantages and drawbacks of chemistry choices for the primary, secondary and tertiary systems in French NPP, for each design particularity and it describes the corresponding operating conditions. Chemistry option proposals are drawn for the future of the French fleet, taking into account the material behaviour and the operation improvement. (orig.)

Operation of the repeating pneumatic injector on TFTR and design of an 8-shot deuterium pellet injector

International Nuclear Information System (INIS)

Combs, S.K.; Milora, S.L.; Foust, C.R.

1985-01-01

The repeating pneumatic hydrogen pellet injector, which was developed at the Oak Ridge National Laboratory (ORNL), has been installed and operated on the Tokamak Fusion Test Reactor (TFTR). The injector combines high-speed extruder and pneumatic acceleration technologies to propel frozen hydrogen isotope pellets repetitively at high speeds. The pellets are transported to the plasma in an injection line that also serves to minimize the gas loading on the torus; the injection line incorporates a fast shutter valve and two stages of guide tubes with intermediate vacuum pumping stations. A remote, stand-alone control and data acquisition system is used for injector and vacuum system operation. In early pellet fueling experiments on TFTR, the injector has been used to deliver deuterium pellets at speeds ranging from 1.0 to 1.5 km/s into plasma discharges. First, single large (nominal 4-mm-dia) pellets provided high densities in TFTR (1.8 x 10 14 cm -3 on axis); after conversion to smaller (nominal 2.7-mm-dia) pellets, up to five pellets were injected at 0.25-s intervals into a plasma discharge, giving a line-averaged density of 1 x 10 14 cm -3 . Operating characteristics and performance of the injector in initial tests on TFTR are presented

A method for aggregating external operating conditions in multi-generation system optimization models

DEFF Research Database (Denmark)

Lythcke-Jørgensen, Christoffer Ernst; Münster, Marie; Ensinas, Adriano Viana

2016-01-01

This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based...... on parameter values rather than time of occurrence, thereby preserving important information on short-term relations between the relevant operating parameters. This is opposed to commonly used methods where data are averaged over chronological periods (months or years), and extreme conditions are hidden...... in the averaged values. The CHOP method is tested in a case study where the operation of a fictive Danish combined heat and power plant is optimized over a historical 5-year period. The optimization model is solved using the full external operating condition dataset, a reduced dataset obtained using the CHOP...

Development of BWR computerized operator support system for emergency conditions

International Nuclear Information System (INIS)

Murata, F.

1984-01-01

A BWR computerized operator support system (COSS) for emergency conditions has been under development for three years. The conceptual design of the system has been settled and some of the subsystems are in the detailed design or manufacturing stage. The principal functions are technical specification monitoring, diagnosis, guidance during emergency conditions, predictive simulation and safety monitoring. Before a reactor trip, alternative operational guidance for anomalous events is provided by utilization of the CTT (cause consequence tree) and FPS (failure propagation simulator). After the trip, operational guidance is based on event-oriented and symptom-oriented methods in association with the safety function monitor. The technical specification monitor controls the readiness monitor and performs surveillance tests of safety systems to maintain plant operational reliability and to ensure correct performance when initiated. The predictive simulator gives the future trends of significant plant parameters. These subsystems are expected to assist the operational personnel. The feasibility of the COSS functions is confirmed separately by off-line simulation. The paper considers the conceptual design, the functions of the subsystems and the off-line simulation results. Each subsystem has shown that useful information to operational personnel is provided. Henceforth these functions will be integrated into a single system and the feasibility will be thoroughly evaluated using a plant simulator which is being separately developed to verify the COSS. (author)

Determination of Pressure Fluctuations in Rotor Bundle of Centrifugal Compressor at Critical Conditions of Operation

Science.gov (United States)

Levashov, V. A.; Lyubchenko, K. Yu

2017-08-01

This article describes the physical processes that occur in the stage flow part of the compressor while it is operating and can create conditions for the occurrence of forced vibrations, which in turn can lead to the destruction of the impellers. Critical conditions of compressor operation are determined. To understand that critical condition of operation is cause of the destruction of the impellers, transient CFD analysis was carried for test stage of compressor. The obtained pressure fluctuation amplitudes allow to evaluate the critical conditions of compressor operation.

Teleportation protocol with non-ideal conditional local operations

Energy Technology Data Exchange (ETDEWEB)

Di Franco, C., E-mail: cdifranco@caesar.ucc.i [Department of Physics, University College Cork, Cork (Ireland); Ballester, D. [School of Mathematics and Physics, Queen' s University, Belfast BT7 1NN (United Kingdom)

2010-07-12

We analyze teleportation protocol when some of receiver's conditional operations are more reliable than others and a non-maximally entangled channel is shared by the two parts. We show that the average fidelity of teleportation can be maximized by choosing properly the basis in which the sender performs her two-qubit measurement.

VERIFICATION OF GEAR DYNAMIC MODEL IN DIFFERENT OPERATING CONDITIONS

Directory of Open Access Journals (Sweden)

Grzegorz PERUŃ

2014-09-01

Full Text Available The article presents the results of verification of the drive system dynamic model with gear. Tests were carried out on the real object in different operating conditions. For the same assumed conditions were also carried out simulation studies. Comparison of the results obtained from those two series of tests helped determine the suitability of the model and verify the possibility of replacing experimental research by simulations with use of dynamic model.

Tribological Evaluation of Candidate Gear Materials Operating Under Light Loads in Highly Humid Conditions

Science.gov (United States)

Dellacorte, Christopher; Thomas, Fransua; Leak, Olivia Ann

2015-01-01

A series of pin-on-disk sliding wear tests were undertaken to identify candidate materials for a pair of lightly loaded timing gears operating under highly humid conditions. The target application involves water purification and thus precludes the use of oil, grease and potentially toxic solid lubricants. The baseline sliding pair is austenitic stainless steel operating against a carbon filled polyimide. The test load and sliding speed (4.9 N, 2.7 m/s) were chosen to represent average contact conditions of the meshing gear teeth. In addition to the baseline materials, the hard superelastic NiTiNOL 60 (60NiTi) was slid against itself, against the baseline polyimide, and against 60NiTi onto which a commercially deposited dry film lubricant (DFL) was applied. The alternate materials were evaluated as potential replacements to achieve a longer wear life and improved dimensional stability for the timing gear application. An attempt was also made to provide solid lubrication to self-mated 60NiTi by rubbing the polyimide against the disk wear track outside the primary 60NiTi-60NiTi contact, a method named stick or transfer-film lubrication. The selected test conditions gave repeatable friction and wear data and smooth sliding surfaces for the baseline materials similar to those in the target application. Friction and wear for self-mated stainless steel were high and erratic. Self-mated 60NiTi gave acceptably low friction (approx. 0.2) and modest wear but the sliding surfaces were rough and potentially unsuitable for the gear application. Tests in which 60NiTi pins were slid against DFL coated 60NiTi and DFL coated stainless steel gave low friction and long wear life. The use of stick lubrication via the secondary polyimide pin provided effective transfer film lubrication to self-mated 60NiTi tribological specimens. Using this approach, friction levels were equal or lower than the baseline polyimide-stainless combination and wear was higher but within data scatter observed

Simulation of worst-case operating conditions for integrated circuits operating in a total dose environment

International Nuclear Information System (INIS)

Bhuva, B.L.

1987-01-01

Degradations in the circuit performance created by the radiation exposure of integrated circuits are so unique and abnormal that thorough simulation and testing of VLSI circuits is almost impossible, and new ways to estimate the operating performance in a radiation environment must be developed. The principal goal of this work was the development of simulation techniques for radiation effects on semiconductor devices. The mixed-mode simulation approach proved to be the most promising. The switch-level approach is used to identify the failure mechanisms and critical subcircuits responsible for operational failure along with worst-case operating conditions during and after irradiation. For precise simulations of critical subcircuits, SPICE is used. The identification of failure mechanisms enables the circuit designer to improve the circuit's performance and failure-exposure level. Identification of worst-case operating conditions during and after irradiation reduces the complexity of testing VLSI circuits for radiation environments. The results of test circuits for failure simulations using a conventional simulator and the new simulator showed significant time savings using the new simulator. The savings in simulation time proved to be circuit topology-dependent. However, for large circuits, the simulation time proved to be orders of magnitude smaller than simulation time for conventional simulators

On the Similarity of Sturm-Liouville Operators with Non-Hermitian Boundary Conditions to Self-Adjoint and Normal Operators

Czech Academy of Sciences Publication Activity Database

Krejčiřík, David; Siegl, Petr; Železný, Jakub

2014-01-01

Roč. 8, č. 1 (2014), s. 255-281 ISSN 1661-8254 R&D Projects: GA MŠk LC06002; GA MŠk LC527; GA ČR GAP203/11/0701 Grant - others:GA ČR(CZ) GD202/08/H072 Institutional support: RVO:61389005 Keywords : Sturm-Liouville operators * non-symmetric Robin boundary conditions * similarity to normal or self-adjoint operators * discrete spectral operator * complex symmetric operator * PT-symmetry * metric operator * C operator * Hilbert- Schmidt operators Subject RIV: BE - Theoretical Physics Impact factor: 0.545, year: 2014

Reject/repeat analysis and the effect prior film viewing has on a department's reject/repeat rate

International Nuclear Information System (INIS)

Clark, P.A.; Hogg, P.

2003-01-01

Purpose: Achieving cost-effectiveness within the NHS is an old initiative but one that has again been highlighted by recent government policies (The New NHS-Modern and Dependable, Stationary Office, London, 1997). It has been reiterated that it is the responsibility of individual Trusts to devise means to provide such a service. Reject/repeat analyses have long been the primary tool used to assess the cost-effectiveness of radiography departments (Quality Assurance in Diagnostic Radiology, WHO, Geneva, 1982). This research paper examines an in-house initiative (viewing patients' previous films) commonly employed in other Health Trusts in order to reduce departmental repeat/reject rates. Method: Three hundred orthopaedic patients with hip, knee and ankle prostheses were included in a reject/repeat analysis. The aim was to investigate whether or not viewing patient's previous relevant radiographs would be advantageous to the practicing radiographer. This was done through an audit cycle consisting of two audit periods each lasting for 3 months. The primary audit period recorded the baseline repeat/reject rate, with the secondary audit period recording the repeat/reject rate under an experimental condition of viewing the relevant radiographs. Results: The baseline audit revealed repeat rates of 33% in orthopaedic patients with hip, knee and ankle prostheses. The availability of prior film viewing to the radiographer reduced this repeat rate to 10.6%. Conclusion: Prior film viewing dramatically reduced the department's repeat/reject rate by 22.4%. This provides scope for significant patient dose reductions as well as reducing departmental film expenses. This is an underestimated initiative and should be used appropriately in routine clinical practice

Online condition monitoring to enable extended operation of nuclear power plants

International Nuclear Information System (INIS)

Meyer, Ryan Michael; Bond, Leonard John; Ramuhalli, Pradeep

2012-01-01

Safe, secure, and economic operation of nuclear power plants will remain of strategic significance. New and improved monitoring will likely have increased significance in the post-Fukushima world. Prior to Fukushima, many activities were already underway globally to facilitate operation of nuclear power plants beyond their initial licensing periods. Decisions to shut down a nuclear power plant are mostly driven by economic considerations. Online condition monitoring is a means to improve both the safety and economics of extending the operating lifetimes of nuclear power plants, enabling adoption of proactive aging management. With regard to active components (e.g., pumps, valves, motors, etc.), significant experience in other industries has been leveraged to build the science base to support adoption of online condition-based maintenance and proactive aging management in the nuclear industry. Many of the research needs are associated with enabling proactive management of aging in passive components (e.g., pipes, vessels, cables, containment structures, etc.). This paper provides an overview of online condition monitoring for the nuclear power industry with an emphasis on passive components. Following the overview, several technology/knowledge gaps are identified, which require addressing to facilitate widespread online condition monitoring of passive components. (author)

How Much of Language Acquisition Does Operant Conditioning Explain?

Science.gov (United States)

Sturdy, Christopher B; Nicoladis, Elena

2017-01-01

Since the 1950s, when Chomsky argued that Skinner's arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC) by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children's language learning.

The influence of impurity and particle control on TMX-U [Tandem Mirror Experiment Upgrade] plasma operation

International Nuclear Information System (INIS)

Allen, S.L.; Yu, T.L.; Foote, J.H.; Pickles, W.L.

1985-11-01

A variety of techniques are used in TMX-U to control impurities and reflux: repeated plasma pulses, glow discharge cleaning (GDC), and gettering. A series of experiments under three different plasma-wall conditions was performed: no wall conditioning after a machine maintenance cycle, a glow-discharge-cleaned wall, and a gettered wall. Several plasma diagnostics to determine the effect of these procedures on TMX-U plasma parameters were used. Spectroscopic measurements indicated that GDC reduced impurities and increased the electron temperature, enabling full-duration beam-sustained plasma operation without a large number of repeated plasma pulses. Gettering further reduced the impurities and the neutral pressure, and this improved condition persisted for several shots after gettering was stopped. Measurements from residual gas analyzers and an end-loss ion spectrometer indicated that hydrogen is present in the plasma during the initial deuterium operation after pumpdown; the hydrogen level decreased after plasma operation with gettering, indicating reduced wall recycling

CFD simulation of a four-loop PWR at asymmetric operation conditions

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jian-Ping; Yan, Li-Ming; Li, Feng-Chen, E-mail: lifch@hit.edu.cn

2016-04-15

Highlights: • A CFD numerical simulation procedure was established for simulating RPV of VVER-1000. • The established CFD approach was validated by comparing with available data. • Thermal hydraulic characteristics under asymmetric operation condition were investigated. • Apparent influences of the shutdown loop on its neighboring loops were obtained. - Abstract: The pressurized water reactor (PWR) with multiple loops may have abnormal working conditions with coolant pumps out of running in some loops. In this paper, a computational fluid dynamics (CFD) numerical study of the four-loop VVER-1000 PWR pressure vessel model was presented. Numerical simulations of the thermohydrodynamic characteristics in the pressure vessel were carried out at different inlet conditions with four and three loops running, respectively. At normal stead-state condition (four-loop running), different parameters were obtained for the full fluid domain, including pressure losses across different parts, pressure, velocity and temperature distributions in the reactor pressure vessel (RPV) and mass flow distribution of the coolant at the inlet of reactor core. The obtained results for pressure losses matched with the experimental reference values of the VVER-1000 PWR at Tianwan nuclear power plant (NPP). For most fuel assemblies (FAs), the inlet flow rates presented a symmetrical distribution about the center under full-loop operation conditions, which accorded with the practical distribution. These results indicate that it is now possible to study the dynamic transition process between different asymmetric operation conditions in a multi-loop PWR using the established CFD method.

Modifications in the operational conditions of the IEA-R1 reactor under continuous 48 hours operation

International Nuclear Information System (INIS)

Moreira, Joao Manoel Losada; Frajndlich, Roberto

1995-01-01

This work shows the required changes in the IEA-R1 reactor for operation at 2 Mw, 48 hours continuously. The principal technical change regards the operating conditions of the reactor, namely, the required excess reactivity which now will amount to 4800 pcm in order to compensate the Xe poisoning at equilibrium at 2 Mw. (author). 6 refs, 1 fig, 1 tab

How do operating conditions affect As(III) removal by iron electrocoagulation?

Science.gov (United States)

Delaire, Caroline; Amrose, Susan; Zhang, Minghui; Hake, James; Gadgil, Ashok

2017-04-01

Iron electrocoagulation (Fe-EC) has been shown to effectively remove arsenic from contaminated groundwater at low cost and has the potential to improve access to safe drinking water for millions of people. Understanding how operating conditions, such as the Fe dosage rate and the O 2 recharge rate, affect arsenic removal at different pH values is crucial to maximize the performance of Fe-EC under economic constraints. In this work, we improved upon an existing computational model to investigate the combined effects of pH, Fe dosage rate, and O 2 recharge rate on arsenic removal in Fe-EC. We showed that the impact of the Fe dosage rate strongly depends on pH and on the O 2 recharge rate, which has important practical implications. We identified the process limiting arsenic removal (As(III) oxidation versus As(V) adsorption) at different pH values, which allowed us to interpret the effect of operating conditions on Fe-EC performance. Finally, we assessed the robustness of the trends predicted by the model, which assumes a constant pH, against lab experiments reproducing more realistic conditions where pH is allowed to drift during treatment as a result of equilibration with atmospheric CO 2 . Our results provide a nuanced understanding of how operating conditions impact arsenic removal by Fe-EC and can inform decisions regarding the operation of this technology in a range of groundwaters. Copyright © 2017 Elsevier Ltd. All rights reserved.

Improved Rosen's conditions on bound states of Schroedinger operators

International Nuclear Information System (INIS)

Exner, P.

1984-01-01

We derive a necessary condition on a Schroedinger operator H=-Δ+V on Lsup(2)(Rsup(d)), d>=3 to have a bound state below a given energy epsilon, and a lower bound to the ground-state energy of H. These conditions are expressed in terms of the potential V alone, and generalize the recent results of Rosen to the dimensions d>3 and to the potentials that are not necessarily rapidly decreasing. Some examples are given

On Solving Intransitivities in Repeated Pairwise Choices

NARCIS (Netherlands)

A. Maas (Arne); Th.G.G. Bezembinder (Thom); P.P. Wakker (Peter)

1995-01-01

textabstractAn operational method is presented for deriving a linear ranking of alternatives from repeated paired comparisons of the alternatives. Intransitivities in the observed preferences are cleared away by the introduction of decision errors of varying importance. An observed preference

Optimization of recirculating laminar air flow in operating room air conditioning systems

Directory of Open Access Journals (Sweden)

Enver Yalcin

2016-04-01

Full Text Available The laminar flow air-conditioning system with 100% fresh air is used in almost all operating rooms without discrimination in Turkey. The laminar flow device which is working with 100% fresh air should be absolutely used in Type 1A operating rooms. However, there is not mandatory to use of 100% fresh air for Type 1B defined as places performed simpler operation. Compared with recirculating laminar flow, energy needs of the laminar flow with 100 % fresh air has been emerged about 40% more than re-circulated air flow. Therefore, when a recirculating laminar flow device is operated instead of laminar flow system with 100% fresh air in the Type 1B operating room, annual energy consumption will be reduced. In this study, in an operating room with recirculating laminar flow, optimal conditions have been investigated in order to obtain laminar flow form by analyzing velocity distributions at various supply velocities by using computational fluid dynamics method (CFD.

Field study evaluation of diffuse ceiling ventilation in classroom during real operating conditions

DEFF Research Database (Denmark)

Kristensen, Martin Heine; Jensen, Jakob Søland; Heiselberg, Per Kvols

2017-01-01

Highlights •Field experimental measurements during real operating conditions. •Evaluation of pressure chamber effect. •Evaluation of displacement effect. •Evaluation of thermal comfort.......Highlights •Field experimental measurements during real operating conditions. •Evaluation of pressure chamber effect. •Evaluation of displacement effect. •Evaluation of thermal comfort....

A conditioned reinforcer did not help to maintain an operant conditioning in the absence of a primary reinforcer in horses.

Science.gov (United States)

Lansade, Léa; Calandreau, Ludovic

2018-01-01

The use of conditioned reinforcers is increasingly promoted in animal training. Surprisingly, the efficiency of their use remains to be demonstrated in horses. This study aimed to determine whether an auditory signal which had previously been associated with a food reward 288 times could be used as a conditioned reinforcer to replace the primary reinforcer in an unrelated operant conditioning procedure. Fourteen horses were divided into two groups of 7: No Reinforcement (NR) and Conditioned Reinforcement (CR). All horses underwent nine sessions of Pavlovian conditioning during which the word "good" was associated with food (32 associations/session). The horses then followed five sessions of operant conditioning (30 trials/session) during which they had to touch a cone signaled by an experimenter to receive a food reward. The last day, horses underwent one test session of the operant response: no reward was given, but the word "good" was said each time a CR horse touched the cone. Nothing was said in the NR group. CR horses did not achieve more correct trials than NR horses during the test. These findings again show that the conditioned reinforcement was ineffective when used instead of the primary reinforcement to maintain conditioning. Copyright © 2017 Elsevier B.V. All rights reserved.

How Much of Language Acquisition Does Operant Conditioning Explain?

Science.gov (United States)

Sturdy, Christopher B.; Nicoladis, Elena

2017-01-01

Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC) by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children’s language learning. PMID:29163295

How Much of Language Acquisition Does Operant Conditioning Explain?

Directory of Open Access Journals (Sweden)

Christopher B. Sturdy

2017-10-01

Full Text Available Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in actual practice, not only resemble but also in fact are examples of operant conditioning (OC by any other name they select. We argue that language acquisition researchers should proceed by first ruling out OC before invoking alternative learning mechanisms. While it is possible that OC cannot explain all of the language acquisition, simple learning mechanisms that work across species may have some explanatory power in children’s language learning.

Marine Vessel Models in Changing Operational Conditions - A Tutorial

DEFF Research Database (Denmark)

Perez, Tristan; Sørensen, Asgeir; Blanke, Mogens

2006-01-01

conditions (VOC). However, since marine systems operate in changing VOCs, there is a need to adapt the models. To date, there is no theory available to describe a general model valid across different VOCs due to the complexity of the hydrodynamic involved. It is believed that system identification could......This tutorial paper provides an introduction, from a systems perspective, to the topic of ship motion dynamics of surface ships. It presents a classification of parametric models currently used for monitoring and control of marine vessels. These models are valid for certain vessel operational...

Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats

Directory of Open Access Journals (Sweden)

Jessica Saalfield

2015-12-01

Full Text Available Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively would affect ethanol conditioned taste aversions 2 days (CTA1 and >3 weeks (CTA2 post-exposure using supersaccharin and saline as conditioning stimuli (CS, respectively. Pair-housed male Sprague-Dawley rats received 4 g/kg i.g. ethanol (25% or water every 48 h from postnatal day (P 25–45 (early AIE or P45-65 (late AIE, or were left non-manipulated (NM. During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5 g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence.

Ionization beam profile monitor for operation under hard environmental conditions

International Nuclear Information System (INIS)

Teterev, Yu.G.; Kaminski, G.; Phi Thanh Huong; Kaminski, G.; Kozik, E.

2010-01-01

The design and the performance of the Ionization Beam Profile Monitor (IBPM) operating on the residual gas ionization principle are described. The main advantage of the constructed device is the non-contact measuring method. Operating under hard environmental conditions it delivers the information about the primary beam position, profile and intensity in 'on-line' regime. It was found out that the device is capable to operate in vacuum in the range of 10 -6 /10 -3 mbar without the loss of the resolution power at the beam current as low as a few nA. The IBPM is prospective for beam profile monitoring due to long time. Emergency situations do not lead to decrease of its operability.

Non-trapping condition for semiclassical Schr dinger operators with matrix-valued potentials.

CERN Document Server

Jecko, T

2004-01-01

We consider semiclassical Schr dinger operators with matrix-valued, long-range, smooth potential, for which different eigenvalues may cross on a codimension one submanifold. We denote by h the semiclassical parameter and we consider energies above the bottom of the essential spectrum. Under some invariance condition on the matricial structure of the potential near the eigenvalues crossing and some structure condition at infinity, we prove that the boundary values of the resolvent at energy lambda, as bounded operators on suitable weighted spaces, are O(1/h) if and only if lambda is a non-trapping energy for all the Hamilton flows generated by the eigenvalues of the operator's symbol.

Classifier-ensemble incremental-learning procedure for nuclear transient identification at different operational conditions

Energy Technology Data Exchange (ETDEWEB)

Baraldi, Piero, E-mail: piero.baraldi@polimi.i [Dipartimento di Energia - Sezione Ingegneria Nucleare, Politecnico di Milano, via Ponzio 34/3, 20133 Milano (Italy); Razavi-Far, Roozbeh [Dipartimento di Energia - Sezione Ingegneria Nucleare, Politecnico di Milano, via Ponzio 34/3, 20133 Milano (Italy); Zio, Enrico [Dipartimento di Energia - Sezione Ingegneria Nucleare, Politecnico di Milano, via Ponzio 34/3, 20133 Milano (Italy); Ecole Centrale Paris-Supelec, Paris (France)

2011-04-15

An important requirement for the practical implementation of empirical diagnostic systems is the capability of classifying transients in all plant operational conditions. The present paper proposes an approach based on an ensemble of classifiers for incrementally learning transients under different operational conditions. New classifiers are added to the ensemble where transients occurring in new operational conditions are not satisfactorily classified. The construction of the ensemble is made by bagging; the base classifier is a supervised Fuzzy C Means (FCM) classifier whose outcomes are combined by majority voting. The incremental learning procedure is applied to the identification of simulated transients in the feedwater system of a Boiling Water Reactor (BWR) under different reactor power levels.

Classifier-ensemble incremental-learning procedure for nuclear transient identification at different operational conditions

International Nuclear Information System (INIS)

Baraldi, Piero; Razavi-Far, Roozbeh; Zio, Enrico

2011-01-01

An important requirement for the practical implementation of empirical diagnostic systems is the capability of classifying transients in all plant operational conditions. The present paper proposes an approach based on an ensemble of classifiers for incrementally learning transients under different operational conditions. New classifiers are added to the ensemble where transients occurring in new operational conditions are not satisfactorily classified. The construction of the ensemble is made by bagging; the base classifier is a supervised Fuzzy C Means (FCM) classifier whose outcomes are combined by majority voting. The incremental learning procedure is applied to the identification of simulated transients in the feedwater system of a Boiling Water Reactor (BWR) under different reactor power levels.

Non-operative diagnosis - effect on repeat-operation rates in the UK breast screening programme

International Nuclear Information System (INIS)

Wallis, M.G.; Cheung, S.; Kearins, O.; Lawrence, G.M.

2009-01-01

Non-operative diagnosis rates in the UK breast screening programme have improved dramatically from 48.8% in 1994/95 (only nine units achieved the then minimum standard of 70%) to 94% in 2005/06 (only seven units failed to achieve the target of 90%). Preoperative and operative history of all 120,550 women diagnosed with screen-detected breast cancer in the UK between April 1994 and March 2006 was derived from different national databases. In 2005/06, 2,790 (17.8%) of the 15,688 women having surgery needed two or more operations. In 2001/02 (non-operative diagnosis rate 87%), the re-operation rate was 23.8% (2,377 of 9,969). Extrapolation backwards to 1994/95 (non-operative diagnosis rate 48.8%) suggests a re-operation rate of 62%. Analysis over the 4 years from April 2002 (n=34,198) demonstrates that 4,089 (12%) women with a correct non-operative diagnosis of invasive disease required additional surgery compared to 1,166 (48%) of women who were under-staged (diagnosed as non-invasive based on core biopsy, but actually suffering from invasive disease). Failure to achieve a non-operative diagnosis of invasive disease (n=1,542) or non-invasive disease (n=2,247) resulted in re-operation rates of 65 and 43% respectively. Given the impact of not having a diagnosis pre-operatively, or of under-staging invasive carcinoma, it seems timely to introduce more sophisticated standards. (orig.)

Cocaine self-administration in social dyads using custom-built operant conditioning chambers.

Science.gov (United States)

Lacy, Ryan T; Strickland, Justin C; Smith, Mark A

2014-10-30

Traditionally, the analysis of intravenous drug self-administration is limited to conditions in which subjects are tested in isolation. This limits the translational appeal of these studies because drug use in humans often occurs in the presence of others. We used custom-built operant conditioning chambers that allowed social dyads visual, olfactory, auditory, and limited tactile contact while concurrently self-administering cocaine. Male rats were trained to respond according to a fixed interval schedule of reinforcement (with a limited hold) in order to determine if patterns of cocaine (0.75mg/kg/infusion) self-administration became more similar over time in social pairs. Cocaine self-administration was tested across five days according to a 10-min fixed interval schedule (with a 5-min limited hold). Quarter-life values (time at which 25% of responses were emitted per interval) were analyzed using intraclass correlations. The total number of reinforcers obtained did not vary across the five days of testing; however, quarter-life values became progressively more similar between individuals within the social dyads. Standard operant conditioning chambers are unable to assess responding in multiple animals due to their small size, the need to prevent subjects from responding on the lever of their partner, and the need to prevent infusion lines from entangling. By using custom-built social operant conditioning chambers, we assessed the effects of social contact on cocaine self-administration. Social operant conditioning chambers can be used as a preclinical method to examine social influences on drug self-administration under conditions that approximate human substance use. Copyright © 2014 Elsevier B.V. All rights reserved.

Risk management of exposure to chemicals under operational conditions

NARCIS (Netherlands)

Langenberg, J.P.

2007-01-01

The HFM panel has decided to install an Exploratory Team, ET-078, which should advise whether or not a Technical Group (TG) should be established on the subject of risk management of exposure to chemicals under operational conditions. This paper described the context and approach of ET-078.

Effects of repeated collaborative retrieval on individual memory vary as a function of recall versus recognition tasks.

Science.gov (United States)

Blumen, Helena M; Rajaram, Suparna

2009-11-01

Our research examines how prior group collaboration modulates later individual memory. We recently showed that repeated collaborative recall sessions benefit later individual recall more than a single collaborative recall session (Blumen & Rajaram, 2008). Current research compared the effects of repeated collaborative recall and repeated collaborative recognition on later individual recall and later individual recognition. A total of 192 participants studied a list of nouns and then completed three successive retrieval sessions in one of four conditions. While two collaborative recall sessions and two collaborative recognition sessions generated comparable levels of individual recall (CRecall-CRecall-I Recall approximately CRecognition-CRecognition-I Recall , Experiment 1a), two collaborative recognition sessions generated greater levels of individual recognition than two collaborative recall sessions (CRecognition-CRecognition- IRecognition > CRecall-CRecall- I Recognition , Experiment 1b). These findings are discussed in terms of two opposing mechanisms that operate during collaborative retrieval-re-exposure and retrieval disruption-and in terms of transfer-appropriate processing across collaborative and individual retrieval sessions.

Indicators for monitoring of safety operation and condition of nuclear power stations

International Nuclear Information System (INIS)

Manova, D.

2001-01-01

A common goal of all employees in the nuclear power field is safety operation of nuclear power stations. The evaluation and control of NPP safety operation are a part of the elements of safety management. The present report is related only to a part of the total assessment and control of the plant safety operation, namely - the indicator system for monitoring of Kozloduy NPP operation and condition. (author)

Application of signature analysis for determining the operational readiness of motor-operated valves under blowdown test conditions

International Nuclear Information System (INIS)

Haynes, H.D.

1988-01-01

In support of the NRC-funded Nuclear Plant Aging Research (NPAR) program, Oak Ridge National Laboratory (ORNL) has carried out a comprehensive aging assessment of Motor-Operated Valves (MOVs). As part of this work, ORNL participated in the Gate Valve Flow Interruption Blowdown (GVFIB) tests carried out in Huntsville, Alabama. The GVFIB tests were intended primarily to determine the behavior of motor-operated gate valves under the temperature, pressure, and flow conditions expected to be experienced by isolation valves in Boiling Water Reactors (BWRs) during a high energy line break (blowdown) outside of containment. In addition, the tests provided an excellent opportunity to evaluate signature analysis methods for determining the operational readiness of the MOVs under those accident conditions. ORNL acquired motor current and torque switch shaft angular position data on two test MOVs during various times of the GVFIB tests. The reduction in operating ''margin'' of both MOVs due to the presence of additional valve running loads imposed by high flow was clearly observed in motor current and torque switch angular position signatures. In addition, the effects of differential pressure, fluid temperature, and line voltage on MOV operations were observed and more clearly understood as a result of utilizing signature analysis techniques. 1 ref.; 16 figs

Operation of static series compensator under distorted utility conditions

DEFF Research Database (Denmark)

Awad, H.; Nelsen, H.; Blaabjerg, Frede

2005-01-01

in the case of distorted grid voltage. Furthermore, a selective harmonic compensation strategy is applied to filter out the grid harmonics. The operation of the SSC under distorted utility conditions and voltage dips is discussed. The validity of the proposed controller is verified by experiments, carried out...... on a 10-kV SSC laboratory setup. Experimental results have shown the ability of the SSC to mitigate voltage dips and harmonics. It is also shown that the proposed controller has improved the transient performance of the SSC even under distorted utility conditions....

Determination of Initial Conditions for the Safety Analysis by Random Sampling of Operating Parameters

International Nuclear Information System (INIS)

Jeong, Hae-Yong; Park, Moon-Ghu

2015-01-01

In most existing evaluation methodologies, which follow a conservative approach, the most conservative initial conditions are searched for each transient scenario through tremendous assessment for wide operating windows or limiting conditions for operation (LCO) allowed by the operating guidelines. In this procedure, a user effect could be involved and a remarkable time and human resources are consumed. In the present study, we investigated a more effective statistical method for the selection of the most conservative initial condition by the use of random sampling of operating parameters affecting the initial conditions. A method for the determination of initial conditions based on random sampling of plant design parameters is proposed. This method is expected to be applied for the selection of the most conservative initial plant conditions in the safety analysis using a conservative evaluation methodology. In the method, it is suggested that the initial conditions of reactor coolant flow rate, pressurizer level, pressurizer pressure, and SG level are adjusted by controlling the pump rated flow, setpoints of PLCS, PPCS, and FWCS, respectively. The proposed technique is expected to contribute to eliminate the human factors introduced in the conventional safety analysis procedure and also to reduce the human resources invested in the safety evaluation of nuclear power plants

20 CFR 662.430 - Under what conditions may One-Stop operators designated to operate in a One-Stop delivery system...

Science.gov (United States)

2010-04-01

... designated to operate in a One-Stop delivery system established prior to the enactment of WIA be designated... DESCRIPTION OF THE ONE-STOP SYSTEM UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT One-Stop Operators § 662.430 Under what conditions may One-Stop operators designated to operate in a One-Stop delivery system...

Projection operators and supplementary conditions for superfields with an arbitrary spin

International Nuclear Information System (INIS)

Sokatchev, E.

1975-01-01

It is shown that a superfield with an external spin j and a nonzero mass contains four non reducible representations of supersymmetry algebra. A general method is proposed for the evolution the representations out of the superfield by using projection operators, derived from Casimir operators. This expansion is also expressed in terms of additional differential conditions

Analysis of the vibrations of the low power ORC turbines operating under conditions of strongly developed hydrodynamic instability

Science.gov (United States)

Kiciński, Jan

2018-01-01

The paper presents the results of the analysis of the dynamic performance of the rotor being a component of the ORC turbine set with the net electrical output of 100 kW and the nominal speed of 9000 rpm. The research was conducted using tools capable of performing the necessary simulation of the system operating under highly unstable conditions, i.e., in a strongly nonlinear regime. In this regard, the author of the paper followed the subsequent phases of whirl/whip formation manifested in the fluid film. Constructional solutions within the scope of the bearing were examined with non-conventional lubricating mediums (low boiling mediums). On the basis of those scientific studies, the decision to build a working prototype of the machine was taken. Such a prototype has already been manufactured, having regard to the outcome of the conducted analyses. The research presented herein produced interesting results showing that, under the conditions of hydrodynamic instability, the phenomena taking place inside the lubricating gap of the slide bearing are not recurrent for each individual rotor revolution, notwithstanding the fact that the external excitation forces acting on the system are fully repeatable. The research tools were presented that allow a detailed qualitative and quantitative description of such phenomena.

Condition for unambiguous state discrimination using local operations and classical communication

International Nuclear Information System (INIS)

Chefles, Anthony

2004-01-01

We obtain a necessary and sufficient condition for a finite set of states of a finite-dimensional multiparticle quantum system to be amenable to unambiguous discrimination using local operations and classical communication. This condition is valid for states which may be mixed, entangled, or both. When the support of the set of states is the entire multiparticle Hilbert space, this condition is found to have an intriguing connection with the theory of entanglement witnesses

Study of the cyclotron operating conditions; Etude des conditions de fonctionnement du cyclotron

Energy Technology Data Exchange (ETDEWEB)

Debraine, P; Bariaud, A; Goldschmidt-Clermont, Y

1948-12-01

This work is a detailed study of the operating conditions of the cyclotron. It analyzes the behaviour of the particles from their first accelerations to their arrival on an external target. Calculations were performed using relativistic formulations in order to make the results usable without any energy level restriction. The obtained results supply some numerical elements for a cyclotron pre-determination and allow a satisfactory visualization of the real phenomena taking place during the accelerations. The shape of the phase change during the successive accelerations has been obtained for a given magnetic field configuration with respect to the operating frequency, to the magnetic field value in the center, and to the accelerating voltage between the dees. Taking into account the limitations due to the accelerating and focussing conditions, the usable phase interval has been determined with respect to the characteristic operating parameters. The study of this phase interval with respect to the accelerating voltage, on the one hand, and with respect to the frequency or to the center magnetic field, on the other hand, has permitted to find again two facts experimentally observed: voltage threshold and dissymmetry of the response curve. The study of radial and axial oscillations has shown the existence of precession phenomena and indicates a maximum limit for the magnetic field variation in order to avoid the disturbances due to oscillations coupling. The study of the ion beam envelope inside the chamber with respect to the initial phases has permitted to determine the optimum shape of the dees and the height of the deflecting channel. Moreover, the influence of various parameters on the ion beam efficiency can be shown using an ideal source. The study of the passing conditions inside the deflecting channel has shown the influence of the separation sheet, has given the dimensions to foresee for the deflecting channel, and has indicated the way to follow to obtain

Quantifying Social Motivation in Mice Using Operant Conditioning.

Science.gov (United States)

Martin, Loren; Iceberg, Erica

2015-08-08

In this protocol, social motivation is measured in mice through a pair of operant conditioning paradigms. To conduct the experiments, two-chambered shuttle boxes were equipped with two operant levers (left and right) and a food receptacle in one chamber, which was then divided from the second chamber by an automated guillotine door covered by a wire grid. Different stimulus mice, rotated across testing days, served as a social stimulus behind the wire grid, and were only visible following the opening of the guillotine door. Test mice were trained to lever press in order to open the door and gain access to the stimulus partner for 15 sec. The number of lever presses required to obtain the social reward progressively increased on a fixed schedule of 3. Testing sessions ended after test mice stopped lever pressing for 5 consecutive minutes. The last reinforced ratio or breakpoint can be used as a quantitative measure of social motivation. For the second paradigm, test mice were trained to discriminate between left and right lever presses in order to obtain either a food reward or the social reward. Mice were rewarded for every 3 presses of each respective lever. The number of food and social rewards can be compared as a measurement of the value placed upon each reward. The ratio of each reward type can also be compared between mouse strains and the change in this ratio can be monitored within testing sessions to measure satiation with a given reward type. Both of these operant conditioning paradigms are highly useful for the quantification of social motivation in mouse models of autism and other disorders of social behavior.

Exploration of robust operating conditions in inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Tromp, John W.; Pomares, Mario; Alvarez-Prieto, Manuel; Cole, Amanda; Ying Hai; Salin, Eric D.

2003-01-01

'Robust' conditions, as defined by Mermet and co-workers for inductively coupled plasma (ICP)-atomic emission spectrometry, minimize matrix effects on analyte signals, and are obtained by increasing power and reducing nebulizer gas flow. In ICP-mass spectrometry (MS), it is known that reduced nebulizer gas flow usually leads to more robust conditions such that matrix effects are reduced. In this work, robust conditions for ICP-MS have been determined by optimizing for accuracy in the determination of analytes in a multi-element solution with various interferents (Al, Ba, Cs, K, Na), by varying power, nebulizer gas flow, sample introduction rate and ion lens voltage. The goal of the work was to determine which operating parameters were the most important in reducing matrix effects, and whether different interferents yielded the same robust conditions. Reduction in nebulizer gas flow and in sample input rate led to a significantly decreased interference, while an increase in power seemed to have a lesser effect. Once the other parameters had been adjusted to their robust values, there was no additional improvement in accuracy attainable by adjusting the ion lens voltage. The robust conditions were universal, since, for all the interferents and analytes studied, the optimum was found at the same operating conditions. One drawback to the use of robust conditions was the slightly reduced sensitivity; however, in the context of 'intelligent' instruments, the concept of 'robust conditions' is useful in many cases

Dental Fear in Children with Repeated Tooth Injuries.

Science.gov (United States)

Negovetić Vranić, Dubravka; Ivančić Jokić, Nataša; Bakarčić, Danko; Carek, Andreja; Rotim, Željko; Verzak, Željko

2016-06-01

Tooth injuries are serious clinical conditions. Some children experience dental trauma only once, while others are more prone to repeated tooth injuries. Repeated dental trauma occurs in 19.4% to 30% of patients. Pain and dental trauma are the most common reasons for fear and anxiety. The main objective of this study was to investigate how dental trauma, as well as repeated dental trauma affects the occurrence and development of dental fear in children. The study was conducted on a random sample of 147 subjects (88 boys and 59 girls) aged 5-8 and 9-12 years. Subjects in both age groups were divided into subroups without dental trauma, with one dental trauma and with repeated dental trauma. The validated Children’s Fear Survey Schedule – Dental Subscale was used on fear assessment. Results showed that only 12.2% of children without trauma, 33.3% with one trauma and 51.7% with repeated trauma were not afraid of injection. Older children had a significantly lower fear of injections, touch of an unknown person, choking, going to the hospital and people in white uniforms. Dentist was not the cause of fear in 65.5% of patients with repeated trauma. With each repeated injury of teeth, the degree of their fear of dental treatment was lower.

Thyroid nodules with nondiagnostic results on repeat fine-needle aspiration biopsy: which nodules should be considered for repeat biopsy or surgery rather than follow-up?

Energy Technology Data Exchange (ETDEWEB)

Eun, Na Lae; Chang, Hang Seok; Gweon, Hye Mi; Kim, Jeong Ah; Youk, Ji Hyun; Son, Eun Jun [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Yoo, Mi Ri [Dept. of Radiology, Dongjak Kyunghee Hospital, Seoul (Korea, Republic of); Park, Ah Young [Dept. of Radiology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of); Moon, Hee Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2016-07-15

The goal of this study was to assess the clinicopathologic and ultrasonographic features of thyroid nodules with nondiagnostic results on repeat ultrasonography (US)-guided fineneedle aspiration biopsy (FNAB) according to size and the number of suspicious findings and to determine the proper management of nodules with consecutive nondiagnostic results. This retrospective study included 297 nodules with nondiagnostic results on repeat FNAB that were evaluated by US over the course of at least 12 months of follow-up, a follow-up biopsy, or an operation. We compared clinical and US variables between benign and malignant nodules in thyroid nodules with repeat nondiagnostic results. The comparison of benign and malignant nodules with repeat nondiagnostic results revealed that age, marked hypoechogenicity, irregular or microlobulated margins, microcalcifications, and nonparallel shape were significantly associated with malignancy. Multivariate logistic regression analysis in malignant nodules revealed that microcalcifications and irregular or microlobulated margins were independently associated with malignancy. Among them, only irregular or microlobulated margins were independently significant as a predictor of malignancy in repeatedly nondiagnostic nodules measuring >10 mm. Using receiver operating characteristic analysis, the best cutoff value for the “number of suspicious findings” between benign and malignant nodules was three in nodules of all sizes, three in nodules measuring ≤10 mm, and two in nodules measuring >10 mm. Irregular or microlobulated margins may be the most frequent US features in repeatedly nondiagnostic nodules >10 mm. The presence of “two or more suspicious findings” can be used as the cutoff for distinguishing benign and malignant nodules.

Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats.

Science.gov (United States)

Saalfield, Jessica; Spear, Linda

2015-12-01

Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively) would affect ethanol conditioned taste aversions 2 days (CTA1) and >3 weeks (CTA2) post-exposure using supersaccharin and saline as conditioning stimuli (CS), respectively. Pair-housed male Sprague-Dawley rats received 4g/kg i.g. ethanol (25%) or water every 48 h from postnatal day (P) 25-45 (early AIE) or P45-65 (late AIE), or were left non-manipulated (NM). During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

High field conditioning of cryogenic RF cavities

International Nuclear Information System (INIS)

Cole, M.; Debiak, T.; Lom, C.; Shephard, W.; Sredniawski, J.

1993-01-01

Space-based and other related accelerators have conditioning and operation requirements that are not found in most machines. The use of cryogenic copper, relatively poor vacuum, and limited power storage and operating time put unusual demands on the high-field conditioning process and present some concerns. Two CW cryogenic engineering model open-quotes sparkerclose quotes cavities have been fabricated and tested to fairly high field levels. Tests included initial and repeated conditioning as well as sustained RF operations. The two cavities were an engineering model TDL and an engineering model RFQ. Both cavities operated at 425 MHz. The DTL was conditioned to 46 MV/m at 100% duty factor (CW) at cryogenic temperature. This corresponds to a gap voltage of 433 kV and a real estate accelerating gradient (energy gain/total cavity length) of 6.97 MV/m. The authors believe this to be record performance for cryo CW operation. During cryo pulsed operation, the same cavity reached 48 MV/m with 200 μsec pulses at 0.5% DF. The RFQ was conditioned to 30 MV/m CW at cryo, 85 kV gap voltage. During a brief period of cryo pulsed operation, the RFQ operated at 46 MV/m, or 125 kV gap voltage. Reconditioning experiments were performed on both cavities and no problems were encountered. It should be noted that the vacuum levels were not very stringent during these tests and no special cleanliness or handling procedures were followed. The results of these tests indicate that cavities can run CW without difficulty at cryogenic temperatures at normal conservative field levels. Higher field operation may well be possible, and if better vacuums are used and more attention is paid to cleanliness, much higher fields may be attainable

A family of DNA repeats in Aspergillus nidulans has assimilated degenerated retrotransposons

DEFF Research Database (Denmark)

Nielsen, M.L.; Hermansen, T.D.; Aleksenko, Alexei Y.

2001-01-01

In the course of a chromosomal walk towards the centromere of chromosome IV of Aspergillus nidulans, several cross- hybridizing genomic cosmid clones were isolated. Restriction mapping of two such clones revealed that their restriction patterns were similar in a region of at least 15 kb, indicati......) phenomenon, first described in Neurospora crassa, may have operated in A. nidulans. The data indicate that this family of repeats has assimilated mobile elements that subsequently degenerated but then underwent further duplications as a part of the host repeats....... the presence of a large repeat. The nature of the repeat was further investigated by sequencing and Southern analysis. The study revealed a family of long dispersed repeats with a high degree of sequence similarity. The number and location of the repeats vary between wild isolates. Two copies of the repeat...

What Can We Learn From Point-of-Care Blood Glucose Values Deleted and Repeated by Nurses?

Science.gov (United States)

Corl, Dawn; Yin, Tom; Ulibarri, May; Lien, Heather; Tylee, Tracy; Chao, Jing; Wisse, Brent E

2018-03-01

Hospitals rely on point-of-care (POC) blood glucose (BG) values to guide important decisions related to insulin administration and glycemic control. Evaluation of POC BG in hospitalized patients is associated with measurement and operator errors. Based on a previous quality improvement (QI) project we introduced an option for operators to delete and repeat POC BG values suspected as erroneous. The current project evaluated our experience with deleted POC BG values over a 2-year period. A retrospective QI project included all patients hospitalized at two regional academic medical centers in the Pacific Northwest during 2014 and 2015. Laboratory Medicine POC BG data were reviewed to evaluate all inpatient episodes of deleted and repeated POC BG. Inpatient operators choose to delete and repeat only 0.8% of all POC BG tests. Hypoglycemic and extreme hyperglycemic BG values are more likely to be deleted and repeated. Of initial values values (18% of all values) are errors. Of values >400 mg/dL, 40% of deleted values (5% of all values) are errors. Not all repeated POC BG values are first deleted. Optimal use of the option to delete and repeat POC BG values values that are measurement/operator errors. Eliminating these errors significantly reduces documented rates of severe hypoglycemia and hyperglycemia, and has the potential to improve patient safety.

Deletion of intragenic tandem repeats in unit C of FLO1 of Saccharomyces cerevisiae increases the conformational stability of flocculin under acidic and alkaline conditions.

Directory of Open Access Journals (Sweden)

Ee Li

Full Text Available Flocculation is an attractive property for Saccaromyces cerevisiae, which plays important roles in fermentation industry and environmental remediation. The process of flocculation is mediated by a family of cell surface flocculins. As one member of flocculins, Flo1 is characterized by four families of repeats (designated as repeat units A, B, C and D in the central domain. It is generally accepted that variation of repeat unit A in length in Flo1 influences the degree of flocculation or specificity for sugar recognization. However, no reports were observed for other repeat units. Here, we compared the flocculation ability and its sensitivity to environmental factors between yeast strain YSF1 carrying the intact FLO1 gene and yeast strains carrying the derived forms of FLO1 with partial or complete deletion of repeats in unit C. No obvious differences in flocculation ability and specificity of carbohydrate recognition were observed among these yeast strains, which indicates the truncated flocculins can stride across the cell wall and cluster the N-terminal domain on the surface of yeast cells as the intact Flo1 thereby improving intercellular binding. However, yeast strains with the truncated flocculins required more mannose to inhibit completely the flocculation, displayed broad tolerance of flocculation to pH fluctuation, and the fewer the repeats in unit C, the stronger adaptability of flocculation to pH change, which was not relevant to the position of deletion. This suggests that more stable active conformation is obtained for flocculin by deletion the repeat unit C in the central domain of Flo1, which was validated further by the higher hydrophobicity on the surface of cells of YSF1c with complete deletion of unit C under neutral and alkaline conditions and the stabilization of GFP conformation by fusion with flocculin with complete deletion of unit C in the central domain.

The Gerbil Jar: A Basic Home Experience in Operant Conditioning.

Science.gov (United States)

Plant, L.

1980-01-01

Explains how a teaching method such as allowing students to raise gerbils at home can encourage students to gain experience with the fundamental techniques of operant conditioning which are otherwise generally unavailable to students in large introductory psychology courses. (DB)

Numerical modelling of multi-vane expander operating conditions in ORC system

Science.gov (United States)

Rak, Józef; Błasiak, Przemysław; Kolasiński, Piotr

2017-11-01

Multi-vane expanders are positive displacement volumetric machines which are nowadays considered for application in micro-power domestic ORC systems as promising alternative to micro turbines and other volumetric expanders. The multi-vane expander features very simple design, low gas flow capacity, low expansion ratios, an advantageous ratio of the power output to the external dimensions and are insensitive to the negative influence of the gas-liquid mixture expansion. Moreover, the multi-vane expander can be easily hermetically sealed, which is one of the key issues in the ORC system design. A literature review indicates that issues concerning the application of multi-vane expanders in such systems, especially related to operating of multi-vane expander with different low-boiling working fluids, are innovative, not fully scientifically described and have the potential for practical implementation. In this paper the results of numerical investigations on multi-vane expander operating conditions are presented. The analyses were performed on three-dimensional numerical model of the expander in ANSYS CFX software. The numerical model of the expander was validated using the data obtained from the experiment carried out on a lab test-stand. Then a series of computational analysis were performed using expanders' numerical model in order to determine its operating conditions under various flow conditions of different working fluids.

Repeatability in Color Measurements of a Spectrophotometer using Different Positioning Devices.

Science.gov (United States)

Hemming, Michael; Kwon, So Ran; Qian, Fang

2015-12-01

This study aimed to evaluate the repeatability of color measurements of an intraoral spectrophotometer with the use of three different methods by two operators. A total of 60 teeth were obtained, comprising 30 human maxillary teeth [central incisors (n = 10); canines (n = 10); molars (n = 10)] and 30 artificial teeth [lateral incisors (n = 10); premolar (n = 20)]. Multiple repeated color measurements were obtained from each tooth using three measuring methods by each of the two operators. Five typodonts with alternating artificial and human teeth were made. Measurements were taken by two operators with the Vita EasyShade spectrophotometer using the custom tray (CT), custom jig (CJ) and free hand (FH) method, twice, at an interval of 2 to 7 days. Friedman test was used to detect difference among the three color measuring methods. Post hoc Wilcoxon signed-rank test with Bonferroni correction applied was used for pair-wise comparison of color measurements among the three methods. Additionally, a paired-sample t-test was used to assess a significant difference between the two duplicated measurements made on the same tooth by the same operator for each color parameter and measuring method. For operator A, mean (SD) overall color change-ΔE* (SD) perceived for FH, CT and CJ were 2.21(2.00), 2.39 (1.58) and 2.86 (1.92), respectively. There was statistically significant difference in perceived ΔE* in FH vs CJ (p = 0.0107). However, there were no significant differences between FH and CT (p = 0.2829) or between CT and CJ (p = 0.1159). For operator B mean ΔE* (SD) for FH, CT and CJ were 3.24 (3.46), 1.95 (1.19) and 2.45 (1.56), respectively. There was a significant difference between FH and CT (p = 0.0031). However, there were no statistically significant differences in ΔE* in FH vs CJ (p = 0.3696) or CT vs CJ (p = 0.0809). The repeatability of color measurements was different among the three measuring methods by operators. Overall, the CT method worked well for both

Operational experience of air washer based ventilation system for power conditioning system of Indus-2

International Nuclear Information System (INIS)

Pandey, R.M.; Baghel, S.L.; Parate, J.K.; Ahlawat, Sandeep; Rawlani, B.K.; Chouksey, Sanjay

2015-01-01

Indus-2 Synchrotron Accelerator requires high quality conditioned uninterrupted AC mains power for their smooth and reliable operation. Three units of 1670 kVA and one unit of 1100 kVA capacity rotary uninterruptible power conditioning systems (UPS) were installed and commissioned. These UPS units require dust free and cool ambient conditions for smooth operation. In order to meet the ventilation requirements, an evaporative cooling system of 80000 cubic meter/hour capacity with filtration units was designed, installed and commissioned in February 2011 and is operational on round-the-clock basis. Evaporative cooling scheme was chosen as has various advantages over a refrigerated system like lower initial capital costs, lower energy usage, lower running costs, less greenhouse gas and it does not contribute to ozone depletion. The ventilation system filters the environment air in stages up to 5 micron level and being conditioned with an automatic controlled soft water circulating system with cooling pads. An instrumentation and control scheme is included in the system to provide the automation requirements for operating 24 x 7 through the year. All the mechanical, hydraulic and electrical devices are maintained by providing preventive maintenance work without affecting the accelerator machine operation. Availability and reliability of the system was analysed based on the failure data. In Year 2014, the ventilation system was upgraded to accommodate standby blower unit, coupling unit and improved quality of supply air with new air conditioning devices. The control panel monitors the condition of air in the UPS hall and maintainsup to 28°C air temperature and 85% maximum relative humidity in round-the clock shift with more than 98% operational reliability. In this paper, we present design philosophy, installation, instrumentation, testing, operation experience and availability of the ventilation system for Power Conditioning System, Indus complex. (author)

Control of hybrid AC/DC microgrid under islanding operational conditions

DEFF Research Database (Denmark)

Ding, G.; Gao, F.; Zhang, S.

2014-01-01

This paper presents control methods for hybrid AC/DC microgrid under islanding operation condition. The control schemes for AC sub-microgrid and DC sub-microgrid are investigated according to the power sharing requirement and operational reliability. In addition, the key control schemes...... of interlinking converter with DC-link capacitor or energy storage, which will devote to the proper power sharing between AC and DC sub-microgrids to maintain AC and DC side voltage stable, is reviewed. Combining the specific control methods developed for AC and DC sub-microgrids with interlinking converter......, the whole hybrid AC/DC microgrid can manage the power flow transferred between sub-microgrids for improving on the operational quality and efficiency....

ANALYSIS OF OPERATING INSTRUMENT LANDING SYSTEM ACCURACY UNDER SIMULATED CONDITIONS

Directory of Open Access Journals (Sweden)

Jerzy MERKISZ

2017-03-01

Full Text Available The instrument landing system (ILS is the most popular landing aid in the world. It is a distance-angled support system for landing in reduced visibility, while its task is the safe conduct of the aircraft from the prescribed course landing on the approach path. The aim of this study is to analyse the correctness of the ILS in simulated conditions. The study was conducted using a CKAS MotionSim5 flight simulator in the Simulation Research Laboratory of the Institute of Combustion Engines and Transport at Poznan University of Technology. With the advancement of technical equipment, it was possible to check the operation of the system in various weather conditions. Studies have shown that the impact of fog, rain and snow on the correct operation of the system is marginal. Significant influence has been observed, however, during landing in strong winds.

Characterization of a thermoelectric cooler based thermal management system under different operating conditions

International Nuclear Information System (INIS)

Russel, M.K.; Ewing, D.; Ching, C.Y.

2013-01-01

The performance of a thermoelectric cooler (TEC) based thermal management system for an electronic packaging design that operates under a range of ambient conditions and system loads is examined using a standard model for the TEC and a thermal resistance network for the other components. Experiments were performed and it was found that the model predictions were in good agreement with the experimental results. An operating envelope is developed to characterize the TEC based thermal management system for peak and off peak operating conditions. Parametric studies were performed to analyze the effect of the number of TEC module(s) in the system, geometric factor of the thermo-elements and the cold to hot side thermal resistances on the system performance. The results showed that there is a tradeoff between the extent of off peak heat fluxes and ambient temperatures when the system can be operated at a low power penalty region and the maximum capacity of the system. - Highlights: ► A model was developed for thermal management systems using thermoelectric coolers. ► Model predictions were in good agreement with experimental results. ► An operating envelope was developed for peak and off peak conditions. ► The effect of the number of thermoelectric coolers on the system was determined.

Relative Effectiveness of Operant Conditioning and Play Therapy in Childhood Schizophrenia

Science.gov (United States)

Ney, Philip G.; And Others

1971-01-01

An experimental study designed to examine the relative effectiveness of operant conditioning and play therapy in improving the communication and social functioning of psychotic children was presented and discussed. (Author)

Influence of CAG Repeat Polymorphism on the Targets of Testosterone Action

Directory of Open Access Journals (Sweden)

Giacomo Tirabassi

2015-01-01

Full Text Available In the last decade, ample evidence has demonstrated the growing importance of androgen receptor (AR CAG repeat polymorphism in andrology. This genetic parameter is able to condition the peripheral effects of testosterone and therefore to influence male sexual function and fertility, cardiovascular risk, body composition, bone metabolism, the risk of prostate and testicular cancer, the psychiatric status, and the onset of neurodegenerative disorders. In this review, we extensively discuss the literature data and identify a role for AR CAG repeat polymorphism in conditioning the systemic testosterone effects. In particular, our main purpose was to provide an updated text able to shed light on the many and often contradictory findings reporting an influence of CAG repeat polymorphism on the targets of testosterone action.

Layered Architectures for Quantum Computers and Quantum Repeaters

Science.gov (United States)

Jones, Nathan C.

This chapter examines how to organize quantum computers and repeaters using a systematic framework known as layered architecture, where machine control is organized in layers associated with specialized tasks. The framework is flexible and could be used for analysis and comparison of quantum information systems. To demonstrate the design principles in practice, we develop architectures for quantum computers and quantum repeaters based on optically controlled quantum dots, showing how a myriad of technologies must operate synchronously to achieve fault-tolerance. Optical control makes information processing in this system very fast, scalable to large problem sizes, and extendable to quantum communication.

A dynamic switching strategy for air-conditioning systems operated in light-thermal-load conditions

International Nuclear Information System (INIS)

Lin, Jin-Long; Yeh, T.-J.; Hwang, Wei-Yang

2009-01-01

Recently, modern air-conditioners have begun to incorporate variable-speed compressors and variable-opening expansion valves, together with feedback control to improve the performance and energy efficiency. However, for the compressor there usually exists a low-speed limit below which its speed can not be continuously modulated unless it is completely turned off. When the air-conditioning system is operated in light-thermal-load conditions, the low-speed limit causes the compressor to run in an on-off manner which can significantly degrade the performance and efficiency. In this paper, a dynamic switching strategy is proposed for such scenarios. The strategy is basically an integration of a cascading control structure, an intuitive switching strategy, and a dynamic compensator. While the control structure provides the nominal performance, the intuitive switching strategy and the dynamic compensator together can account for the compressor's low-speed limitation. Theoretical analysis reveals that when the output matrix of the dynamic compensator is chosen properly, the proposed strategy can effectively reduce the output error caused by the on-off operation of the compressor. Experiments also demonstrate that the proposed strategy can simultaneously provide better regulation for the indoor temperature and improve the energy efficiency at steady state.

An Operation Control Strategy for the Connected Maglev Trains Based on Vehicle-Borne Battery Condition Monitoring

Directory of Open Access Journals (Sweden)

Wenjing Zhang

2018-01-01

Full Text Available Vehicle-borne battery condition is an important factor affecting the efficiency of the maglev train operation and other connected ones. To effectively eliminate the influence of the battery condition and improve the operation efficiency of the connected maglev trains, an operation control strategy is proposed to guarantee train operation safety. First, based on Internet of Things, a sensor network is designed to monitor vehicle-borne battery condition in each vehicle of the train. Second, the train Operation Control System collects battery data of all vehicles in a maglev train by Train Communication Network. Third, all connected maglev trains share the battery data via a 38 GHz directional Radio Communication System and adjust operation control strategy accordingly. Simulation results indicate that the proposed strategy can guarantee the operation safety of the connected maglev trains.

Structural characterization and condition for measurement statistics preservation of a unital quantum operation

International Nuclear Information System (INIS)

Lee, Kai-Yan; Fung, Chi-Hang Fred; Chau, H F

2013-01-01

We investigate the necessary and sufficient condition for a convex cone of positive semidefinite operators to be fixed by a unital quantum operation ϕ acting on finite-dimensional quantum states. By reducing this problem to the problem of simultaneous diagonalization of the Kraus operators associated with ϕ, we can completely characterize the kinds of quantum states that are fixed by ϕ. Our work has several applications. It gives a simple proof of the structural characterization of a unital quantum operation that acts on finite-dimensional quantum states—a result not explicitly mentioned in earlier studies. It also provides a necessary and sufficient condition for determining what kind of measurement statistics is preserved by a unital quantum operation. Finally, our result clarifies and extends the work of Størmer by giving a proof of a reduction theorem on the unassisted and entanglement-assisted classical capacities, coherent information, and minimal output Renyi entropy of a unital channel acting on a finite-dimensional quantum state. (paper)

Operating conditions of T.B.P. line uranium purification plant, for uranium dioxide production

International Nuclear Information System (INIS)

Vardich, R.N.; La Gamma, A.M.; Anasco, R.; Soler, S.M.G. de; Isnardi, E.; Gea, V.; Chiaraviglio, R.; Matyjasczyk, E.; Aramayo, R.

1992-01-01

In this contribution are presented the operative conditions and the results obtained step of the Uranium dioxide production plant of Argentina. The refining step involve the Uranium concentrate dissolution, the silica ageing, the filtration and liquid - liquid extraction with n-tributyl phosphate solution in kerosene. The established operative conditions allow to obtain Uranyl nitrate solutions of nuclear purity in industrial scale. (author)

Repeated elicitation of the acoustic startle reflex leads to sensitisation in subsequent avoidance behaviour and induces fear conditioning

Directory of Open Access Journals (Sweden)

Janik Vincent M

2011-04-01

Full Text Available Abstract Background Autonomous reflexes enable animals to respond quickly to potential threats, prevent injury and mediate fight or flight responses. Intense acoustic stimuli with sudden onsets elicit a startle reflex while stimuli of similar intensity but with longer rise times only cause a cardiac defence response. In laboratory settings, habituation appears to affect all of these reflexes so that the response amplitude generally decreases with repeated exposure to the stimulus. The startle reflex has become a model system for the study of the neural basis of simple learning processes and emotional processing and is often used as a diagnostic tool in medical applications. However, previous studies did not allow animals to avoid the stimulus and the evolutionary function and long-term behavioural consequences of repeated startling remain speculative. In this study we investigate the follow-up behaviour associated with the startle reflex in wild-captured animals using an experimental setup that allows individuals to exhibit avoidance behaviour. Results We present evidence that repeated elicitation of the acoustic startle reflex leads to rapid and pronounced sensitisation of sustained spatial avoidance behaviour in grey seals (Halichoerus grypus. Animals developed rapid flight responses, left the exposure pool and showed clear signs of fear conditioning. Once sensitised, seals even avoided a known food source that was close to the sound source. In contrast, animals exposed to non-startling (long rise time stimuli of the same maximum sound pressure habituated and flight responses waned or were absent from the beginning. The startle threshold of grey seals expressed in units of sensation levels was comparable to thresholds reported for other mammals (93 dB. Conclusions Our results demonstrate that the acoustic startle reflex plays a crucial role in mediating flight responses and strongly influences the motivational state of an animal beyond a short

Extending In Vitro Conditioning in "Aplysia" to Analyze Operant and Classical Processes in the Same Preparation

Science.gov (United States)

Brembs, Bjorn; Baxter, Douglas A.; Byrne, John H.

2004-01-01

Operant and classical conditioning are major processes shaping behavioral responses in all animals. Although the understanding of the mechanisms of classical conditioning has expanded significantly, the understanding of the mechanisms of operant conditioning is more limited. Recent developments in "Aplysia" are helping to narrow the gap in the…

Numerical modelling of multi-vane expander operating conditions in ORC system

Directory of Open Access Journals (Sweden)

Rak Józef

2017-01-01

Full Text Available Multi-vane expanders are positive displacement volumetric machines which are nowadays considered for application in micro-power domestic ORC systems as promising alternative to micro turbines and other volumetric expanders. The multi-vane expander features very simple design, low gas flow capacity, low expansion ratios, an advantageous ratio of the power output to the external dimensions and are insensitive to the negative influence of the gas-liquid mixture expansion. Moreover, the multi-vane expander can be easily hermetically sealed, which is one of the key issues in the ORC system design. A literature review indicates that issues concerning the application of multi-vane expanders in such systems, especially related to operating of multi-vane expander with different low-boiling working fluids, are innovative, not fully scientifically described and have the potential for practical implementation. In this paper the results of numerical investigations on multi-vane expander operating conditions are presented. The analyses were performed on three-dimensional numerical model of the expander in ANSYS CFX software. The numerical model of the expander was validated using the data obtained from the experiment carried out on a lab test-stand. Then a series of computational analysis were performed using expanders' numerical model in order to determine its operating conditions under various flow conditions of different working fluids.

Methodology for selection of attributes and operating conditions for SVM-Based fault locator's

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Debbie Johan Arredondo Arteaga

2017-01-01

Full Text Available Context: Energy distribution companies must employ strategies to meet their timely and high quality service, and fault-locating techniques represent and agile alternative for restoring the electric service in the power distribution due to the size of distribution services (generally large and the usual interruptions in the service. However, these techniques are not robust enough and present some limitations in both computational cost and the mathematical description of the models they use. Method: This paper performs an analysis based on a Support Vector Machine for the evaluation of the proper conditions to adjust and validate a fault locator for distribution systems; so that it is possible to determine the minimum number of operating conditions that allow to achieve a good performance with a low computational effort. Results: We tested the proposed methodology in a prototypical distribution circuit, located in a rural area of Colombia. This circuit has a voltage of 34.5 KV and is subdivided in 20 zones. Additionally, the characteristics of the circuit allowed us to obtain a database of 630.000 records of single-phase faults and different operating conditions. As a result, we could determine that the locator showed a performance above 98% with 200 suitable selected operating conditions. Conclusions: It is possible to improve the performance of fault locators based on Support Vector Machine. Specifically, these improvements are achieved by properly selecting optimal operating conditions and attributes, since they directly affect the performance in terms of efficiency and the computational cost.

Model development and optimization of operating conditions to maximize PEMFC performance by response surface methodology

International Nuclear Information System (INIS)

Kanani, Homayoon; Shams, Mehrzad; Hasheminasab, Mohammadreza; Bozorgnezhad, Ali

2015-01-01

Highlights: • The optimization of the operating parameters in a serpentine PEMFC is done using RSM. • The RSM model can predict the cell power over the wide range of operating conditions. • St-An, St-Ca and RH-Ca have an optimum value to obtain the best performance. • The interactions of the operating conditions affect the output power significantly. • The cathode and anode stoichiometry are the most effective parameters on the power. - Abstract: Optimization of operating conditions to obtain maximum power in PEMFCs could have a significant role to reduce the costs of this emerging technology. In the present experimental study, a single serpentine PEMFC is used to investigate the effects of operating conditions on the electrical power production of the cell. Four significant parameters including cathode stoichiometry, anode stoichiometry, gases inlet temperature, and cathode relative humidity are studied using Design of Experiment (DOE) to obtain an optimal power. Central composite second order Response Surface Methodology (RSM) is used to model the relationship between goal function (power) and considered input parameters (operating conditions). Using this statistical–mathematical method leads to obtain a second-order equation for the cell power. This model considers interactions and quadratic effects of different operating conditions and predicts the maximum or minimum power production over the entire working range of the parameters. In this range, high stoichiometry of cathode and low stoichiometry of anode results in the minimum cell power and contrary the medium range of fuel and oxidant stoichiometry leads to the maximum power. Results show that there is an optimum value for the anode stoichiometry, cathode stoichiometry and relative humidity to reach the best performance. The predictions of the model are evaluated by experimental tests and they are in a good agreement for different ranges of the parameters

Operational Meanings of Orders of Observables Defined through Quantum Set Theories with Different Conditionals

Directory of Open Access Journals (Sweden)

Masanao Ozawa

2017-01-01

Full Text Available In quantum logic there is well-known arbitrariness in choosing a binary operation for conditional. Currently, we have at least three candidates, called the Sasaki conditional, the contrapositive Sasaki conditional, and the relevance conditional. A fundamental problem is to show how the form of the conditional follows from an analysis of operational concepts in quantum theory. Here, we attempt such an analysis through quantum set theory (QST. In this paper, we develop quantum set theory based on quantum logics with those three conditionals, each of which defines different quantum logical truth value assignment. We show that those three models satisfy the transfer principle of the same form to determine the quantum logical truth values of theorems of the ZFC set theory. We also show that the reals in the model and the truth values of their equality are the same for those models. Interestingly, however, the order relation between quantum reals significantly depends on the underlying conditionals. We characterize the operational meanings of those order relations in terms of joint probability obtained by the successive projective measurements of arbitrary two observables. Those characterizations clearly show their individual features and will play a fundamental role in future applications to quantum physics.

Significance of Operating Environment in Condition Monitoring of Large Civil Structures

Directory of Open Access Journals (Sweden)

Sreenivas Alampalli

1999-01-01

Full Text Available Success of remote long-term condition monitoring of large civil structures and developing calibrated analytical models for damage detection, depend significantly on establishing accurate baseline signatures and their sensitivity. Most studies reported in the literature concentrated on the effect of structural damage on modal parameters without emphasis on reliability of modal parameters. Thus, a field bridge structure was studied for the significance of operating conditions in relation to baseline signatures. Results indicate that in practice, civil structures should be monitored for at least one full cycle of in-service environmental changes before establishing baselines for condition monitoring or calibrating finite-element models. Boundary conditions deserve special attention.

Detection and classification of alarm threshold violations in condition monitoring systems working in highly varying operational conditions

Science.gov (United States)

Strączkiewicz, M.; Barszcz, T.; Jabłoński, A.

2015-07-01

All commonly used condition monitoring systems (CMS) enable defining alarm thresholds that enhance efficient surveillance and maintenance of dynamic state of machinery. The thresholds are imposed on the measured values such as vibration-based indicators, temperature, pressure, etc. For complex machinery such as wind turbine (WT) the total number of thresholds might be counted in hundreds multiplied by the number of operational states. All the parameters vary not only due to possible machinery malfunctions, but also due to changes in operating conditions and these changes are typically much stronger than the former ones. Very often, such a behavior may lead to hundreds of false alarms. Therefore, authors propose a novel approach based on parameterized description of the threshold violation. For this purpose the novelty and severity factors are introduced. The first parameter refers to the time of violation occurrence while the second one describes the impact of the indicator-increase to the entire machine. Such approach increases reliability of the CMS by providing the operator with the most useful information of the system events. The idea of the procedure is presented on a simulated data similar to those from a wind turbine.

Detection and classification of alarm threshold violations in condition monitoring systems working in highly varying operational conditions

International Nuclear Information System (INIS)

Strączkiewicz, M; Barszcz, T; Jabłoński, A

2015-01-01

All commonly used condition monitoring systems (CMS) enable defining alarm thresholds that enhance efficient surveillance and maintenance of dynamic state of machinery. The thresholds are imposed on the measured values such as vibration-based indicators, temperature, pressure, etc. For complex machinery such as wind turbine (WT) the total number of thresholds might be counted in hundreds multiplied by the number of operational states. All the parameters vary not only due to possible machinery malfunctions, but also due to changes in operating conditions and these changes are typically much stronger than the former ones. Very often, such a behavior may lead to hundreds of false alarms. Therefore, authors propose a novel approach based on parameterized description of the threshold violation. For this purpose the novelty and severity factors are introduced. The first parameter refers to the time of violation occurrence while the second one describes the impact of the indicator-increase to the entire machine. Such approach increases reliability of the CMS by providing the operator with the most useful information of the system events. The idea of the procedure is presented on a simulated data similar to those from a wind turbine. (paper)

Detection of Partial Demagnetization Fault in PMSMs Operating under Nonstationary Conditions

DEFF Research Database (Denmark)

Wang, Chao; Delgado Prieto, Miguel; Romeral, Luis

2016-01-01

Demagnetization fault detection of in-service Permanent Magnet Synchronous Machines (PMSMs) is a challenging task because most PMSMs operate under nonstationary circumstances in industrial applications. A novel approach based on tracking characteristic orders of stator current using Vold-Kalman F......Demagnetization fault detection of in-service Permanent Magnet Synchronous Machines (PMSMs) is a challenging task because most PMSMs operate under nonstationary circumstances in industrial applications. A novel approach based on tracking characteristic orders of stator current using Vold......-Kalman Filter is proposed to detect the partial demagnetization fault in PMSMs running at nonstationary conditions. Amplitude of envelope of the fault characteristic orders is used as fault indictor. Experimental results verify the superiority of the proposed method on partial demagnetization online fault...... detection of PMSMs under various speed and load conditions....

Significance of Operating Environment in Condition Monitoring of Large Civil Structures

OpenAIRE

Alampalli, Sreenivas

1999-01-01

Success of remote long-term condition monitoring of large civil structures and developing calibrated analytical models for damage detection, depend significantly on establishing accurate baseline signatures and their sensitivity. Most studies reported in the literature concentrated on the effect of structural damage on modal parameters without emphasis on reliability of modal parameters. Thus, a field bridge structure was studied for the significance of operating conditions in relation to bas...

The Establishment and Administration of Operant Conditioning Programs in a State Hospital for the Retarded.

Science.gov (United States)

Ball, Thomas S., Ed.

Seven articles treat the establishment of operant conditioning programs for the mentally retarded at Pacific State Hospital in California. Emphasis is on the administrative rather than the demonstration of research aspects of operant conditioning programs. Following an introduction and overview, the medical director's point of view on operant…

On the radiation mechanism of repeating fast radio bursts

Science.gov (United States)

Lu, Wenbin; Kumar, Pawan

2018-06-01

Recent observations show that fast radio bursts (FRBs) are energetic but probably non-catastrophic events occurring at cosmological distances. The properties of their progenitors are largely unknown in spite of many attempts to determine them using the event rate, duration, and energetics. Understanding the radiation mechanism for FRBs should provide the missing insights regarding their progenitors, which is investigated in this paper. The high brightness temperatures (≳1035 K) of FRBs mean that the emission process must be coherent. Two general classes of coherent radiation mechanisms are considered - maser and the antenna mechanism. We use the observed properties of the repeater FRB 121102 to constrain the plasma conditions needed for these two mechanisms. We have looked into a wide variety of maser mechanisms operating in either vacuum or plasma and find that none of them can explain the high luminosity of FRBs without invoking unrealistic or fine-tuned plasma conditions. The most favourable mechanism is antenna curvature emission by coherent charge bunches where the burst is powered by magnetic reconnection near the surface of a magnetar (B ≳ 1014 G). We show that the plasma in the twisted magnetosphere of a magnetar may be clumpy due to two-stream instability. When magnetic reconnection occurs, the pre-existing density clumps may provide charge bunches for the antenna mechanism to operate. This model should be applicable to all FRBs that have multiple outbursts like FRB 121102.

Operant conditioning of neural activity in freely behaving monkeys with intracranial reinforcement.

Science.gov (United States)

Eaton, Ryan W; Libey, Tyler; Fetz, Eberhard E

2017-03-01

Operant conditioning of neural activity has typically been performed under controlled behavioral conditions using food reinforcement. This has limited the duration and behavioral context for neural conditioning. To reward cell activity in unconstrained primates, we sought sites in nucleus accumbens (NAc) whose stimulation reinforced operant responding. In three monkeys, NAc stimulation sustained performance of a manual target-tracking task, with response rates that increased monotonically with increasing NAc stimulation. We recorded activity of single motor cortex neurons and documented their modulation with wrist force. We conditioned increased firing rates with the monkey seated in the training booth and during free behavior in the cage using an autonomous head-fixed recording and stimulating system. Spikes occurring above baseline rates triggered single or multiple electrical pulses to the reinforcement site. Such rate-contingent, unit-triggered stimulation was made available for periods of 1-3 min separated by 3-10 min time-out periods. Feedback was presented as event-triggered clicks both in-cage and in-booth, and visual cues were provided in many in-booth sessions. In-booth conditioning produced increases in single neuron firing probability with intracranial reinforcement in 48 of 58 cells. Reinforced cell activity could rise more than five times that of non-reinforced activity. In-cage conditioning produced significant increases in 21 of 33 sessions. In-cage rate changes peaked later and lasted longer than in-booth changes, but were often comparatively smaller, between 13 and 18% above non-reinforced activity. Thus intracranial stimulation reinforced volitional increases in cortical firing rates during both free behavior and a controlled environment, although changes in the latter were more robust. NEW & NOTEWORTHY Closed-loop brain-computer interfaces (BCI) were used to operantly condition increases in muscle and neural activity in monkeys by delivering

A phase angle based diagnostic scheme to planetary gear faults diagnostics under non-stationary operational conditions

Science.gov (United States)

Feng, Ke; Wang, Kesheng; Ni, Qing; Zuo, Ming J.; Wei, Dongdong

2017-11-01

Planetary gearbox is a critical component for rotating machinery. It is widely used in wind turbines, aerospace and transmission systems in heavy industry. Thus, it is important to monitor planetary gearboxes, especially for fault diagnostics, during its operational conditions. However, in practice, operational conditions of planetary gearbox are often characterized by variations of rotational speeds and loads, which may bring difficulties for fault diagnosis through the measured vibrations. In this paper, phase angle data extracted from measured planetary gearbox vibrations is used for fault detection under non-stationary operational conditions. Together with sample entropy, fault diagnosis on planetary gearbox is implemented. The proposed scheme is explained and demonstrated in both simulation and experimental studies. The scheme proves to be effective and features advantages on fault diagnosis of planetary gearboxes under non-stationary operational conditions.

Validation of AEGIS/SCOPE2 system through actual core follow calculations with irregular operational conditions

International Nuclear Information System (INIS)

Tabuchi, M.; Tatsumi, M.; Ohoka, Y.; Nagano, H.; Ishizaki, K.

2017-01-01

This paper describes overview of AEGIS/SCOPE2 system, an advanced in-core fuel management system for pressurized water reactors, and its validation results of actual core follow calculations including irregular operational conditions. AEGIS and SCOPE2 codes adopt more detailed and accurate calculation models compared to the current core design codes while computational cost is minimized with various techniques on numerical and computational algorithms. Verification and validation of AEGIS/SCOPE2 has been intensively performed to confirm validity of the system. As a part of the validation, core follow calculations have been carried out mainly for typical operational conditions. After the Fukushima Daiichi nuclear power plant accident, however, all the nuclear reactors in Japan suffered from long suspension and irregular operational conditions. In such situations, measured data in the restart and operation of the reactors should be good examinations for validation of the codes. Therefore, core follow calculations were carried out with AEGIS/SCOPE2 for various cases including zero power reactor physics tests with irregular operational conditions. Comparisons between measured data and predictions by AEGIS/SCOPE2 revealed the validity and robustness of the system. (author)

Appetitive operant conditioning in mice: heritability and dissociability of training stages

Directory of Open Access Journals (Sweden)

Hemi A I Malkki

2010-11-01

Full Text Available To study the heritability of different training stages of appetitive operant conditioning, we carried out behavioural screening of 5 standard inbred mouse strains, 28 recombinant-inbred (BxD mouse lines and their progenitor strains C57BL/6J and DBA/2J. We also computed correlations between successive training stages to study whether learning deficits at an advanced stage of operant conditioning may be dissociated from normal performance in preceding phases of training.The training consisted of two phases: an operant nose poking phase, in which mice learned to collect a sucrose pellet from a food magazine by nose poking, and an operant lever press and nose poking phase, in which mice had to execute a sequence of these two actions to collect a food pellet. As a measure of magazine oriented exploration, we also studied the nose poke entries in the food magazine during the intertrial intervals at the beginning of the first session of the nose-poke training phase.We found significantly heritable components in initial magazine checking behaviour, operant nose-poking and lever press-nose poking. Performance levels in these phases were positively correlated, but several individual strains were identified that showed poor lever press-nose poking while performing well in preceding training stages. Quantitative trait loci mapping revealed suggestive likelihood ratio statistic peaks for initial magazine checking behaviour and lever press – nose poking. These findings indicate that consecutive stages towards more complex operant behavior show significant heritable components, as well as dissociability between stages in specific mouse strains. These heritable components may reside in different chromosomal areas.

Mobility and cloud: operating in intermittent, austere network conditions

OpenAIRE

Wee, Toon Joo; Ling, Yu Xian Eldine

2014-01-01

Approved for public release; distribution is unlimited Cloud computing is emerging as the mainstream platform for a range of on-demand applications, services, and infrastructure. Before the benefits of cloud computing are realized, several technology challenges must be addressed. Operating in intermittent and austere network conditions is one of such challenges, which navy ships face when communicating with land-based cloud computing environments. Given limited bandwidth and intermittent c...

Fan Efficiency Improvement via Changing Guide Blade Shape Under Various Operating Conditions

Directory of Open Access Journals (Sweden)

G. I. Zamolodchikov

2017-01-01

Full Text Available The aim of this study is to examine the influence of sweep and tangential blade lean the guide vanes (GV on the pressure losses in the blade row, and development of an approach to creating the GV with a rationally-shaped blades to ensure increased efficiency in the partial operating conditions.A numerical simulation method was used for research. As an object to be studied, was used an axial fan comprising an impeller and a GV, which were profiled to have constant circulation of velocity in radius. Verification of numerical simulation was based on the experimental data of fan. It comprised a GV with a straight blade and a circular-arc blade, with an impeller remained stationary in both cases. Among the turbulence models under consideration, preference is given to k-ω, as under operating conditions close to design ones, its result falls within the confidence span of the experimental characteristics, and at much higher and lower discharge coefficients a discrepancy is 4% at most.  In addition to the characteristics, the fields of pressure losses in GV have been analyzed. Numerical modeling allowed us to have a well-reproduced structure of losses in the stationary blade row.Analysis of pressure loss fields has shown that in the original GV near the hub, on the blade back, under design conditions a flow breakdown takes off. In view of the research, was designed a new GV with a modified blade geometry. The GV blade axis near the hub was bent in the circumferential direction by 0.1 length of the blade. In the near-hub cross-sections the blade chord was increased by 10%.The results of numerical simulation have shown that, with the flow less than the designed one, a change of just the GV blade tip sections leads to reduced break-down zone near the hub by about 40% under both operating conditions without raising profile losses and to improved fan efficiency, which reduces fan drive power consumption under typical operating conditions in the propulsion

Preliminary Two-Phase Terry Turbine Nozzle Models for RCIC Off-Design Operation Conditions

Energy Technology Data Exchange (ETDEWEB)

Zhao, Haihua [Idaho National Lab. (INL), Idaho Falls, ID (United States); O' Brien, James [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2017-06-12

This report presents the effort to extend the single-phase analytical Terry turbine model to cover two-phase off-design conditions. The work includes: (1) adding well-established two-phase choking models – the Isentropic Homogenous Equilibrium Model (IHEM) and Moody’s model, and (2) theoretical development and implementation of a two-phase nozzle expansion model. The two choking models provide bounding cases for the two-phase choking mass flow rate. The new two-phase Terry turbine model uses the choking models to calculate the mass flow rate, the critical pressure at the nozzle throat, and steam quality. In the divergent stage, we only consider the vapor phase with a similar model for the single-phase case by assuming that the liquid phase would slip along the wall with a much slower speed and will not contribute the impulse on the rotor. We also modify the stagnation conditions according to two-phase choking conditions at the throat and the cross-section areas for steam flow at the nozzle throat and at the nozzle exit. The new two-phase Terry turbine model was benchmarked with the same steam nozzle test as for the single-phase model. Better agreement with the experimental data is observed than from the single-phase model. We also repeated the Terry turbine nozzle benchmark work against the Sandia CFD simulation results with the two-phase model for the pure steam inlet nozzle case. The RCIC start-up tests were simulated and compared with the single-phase model. Similar results are obtained. Finally, we designed a new RCIC system test case to simulate the self-regulated Terry turbine behavior observed in Fukushima accidents. In this test, a period inlet condition for the steam quality varying from 1 to 0 is applied. For the high quality inlet period, the RCIC system behaves just like the normal operation condition with a high pump injection flow rate and a nominal steam release rate through the turbine, with the net addition of water to the primary system; for

Experimental study on acquisition of knowledge through repeated education and training

International Nuclear Information System (INIS)

Sasou, Kunihide; Suzuki, Tomohiro; Yoshimura, Seiichi; Kitamura, Masaharu.

1997-01-01

Considering the educational methodology to bring up nuclear power plant operators, the experiments are conducted to discuss the relation between the educational backgrounds of subjects and the knowledge acquired through education and training and also to discuss the effects of repeated training on knowledge acquisition. The results show that the knowledge the subjects obtained through the training depends on their educational backgrounds. The subjects with the higher educational backgrounds seem to properly reorganize the knowledge for the operations with using their deep and meta knowledge. Therefore they can create anticipative responses and easily identify causes of events. The results also show that the repeated education and training given to the subjects with weaker backgrounds makes their knowledge reorganized and their ability becomes closer to the subjects' one with higher educational backgrounds. These results indicate that the knowledge acquired in the earlier stage of the education and training depends on the subjects' educational backgrounds. However, the repeated education and training compensates for the difference. It is also suggested that it will be possible to bring up operators more effectively and properly if the existence of people with different educational backgrounds is recognized and the education/training depending on the educational backgrounds are realized. (author)

[Microbial air purity in hospitals. Operating theatres with air conditioning system].

Science.gov (United States)

Krogulski, Adam; Szczotko, Maciej

2010-01-01

The aim of this study was to show the influence of air conditioning control for microbial contamination of air inside the operating theatres equipped with correctly working air-conditioning system. This work was based on the results of bacteria and fungi concentration in hospital air obtained since 2001. Assays of microbial air purity conducted on atmospheric air in parallel with indoor air demonstrated that air filters applied in air-conditioning systems worked correctly in every case. To show the problem of fluctuation of bacteria concentration more precisely, every sequences of single results from successive measure series were examined independently.

Assessment of biogas production from MBT waste under different operating conditions

Energy Technology Data Exchange (ETDEWEB)

Pantini, Sara, E-mail: pantini@ing.uniroma2.it [Department of Civil Engineering and Computer Science Engineering, University of Rome “Tor Vergata”, Via del Politecnico, 1, 00133 Rome (Italy); Verginelli, Iason; Lombardi, Francesco [Department of Civil Engineering and Computer Science Engineering, University of Rome “Tor Vergata”, Via del Politecnico, 1, 00133 Rome (Italy); Scheutz, Charlotte; Kjeldsen, Peter [Department of Environmental Engineering, Technical University of Denmark, Miljoevej, Building 113, DK-2800 Kgs. Lyngby (Denmark)

2015-09-15

Highlights: • BMP test displayed high gas potential generation capacity of MBT waste. • Strong inhibition effects were observed due to ammonia and VFA accumulation. • Waste water content was found as the key parameter limiting gas generation. • First order k-values were determined for different operating conditions. - Abstract: In this work, the influence of different operating conditions on the biogas production from mechanically–biologically treated (MBT) wastes is investigated. Specifically, different lab-scale anaerobic tests varying the water content (26–43% w/w up to 75% w/w), the temperature (from 20 to 25 °C up to 55 °C) and the amount of inoculum have been performed on waste samples collected from a full-scale Italian MBT plant. For each test, the gas generation yield and, where applicable, the first-order gas generation rates were determined. Nearly all tests were characterised by a quite long lag-phase. This result was mainly ascribed to the inhibition effects resulting from the high concentrations of volatile fatty acids (VFAs) and ammonia detected in the different stages of the experiments. Furthermore, water content was found as one of the key factor limiting the anaerobic biological process. Indeed, the experimental results showed that when the moisture was lower than 32% w/w, the methanogenic microbial activity was completely inhibited. For the higher water content tested (75% w/w), high values of accumulated gas volume (up to 150 Nl/kgTS) and a relatively short time period to deplete the MBT waste gas generation capacity were observed. At these test conditions, the effect of temperature became evident, leading to gas generation rates of 0.007 d{sup −1} at room temperature that increased to 0.03–0.05 d{sup −1} at 37 °C and to 0.04–0.11 d{sup −1} at 55 °C. Overall, the obtained results highlighted that the operative conditions can drastically affect the gas production from MBT wastes. This suggests that particular caution

LHCb Conditions database operation assistance systems

International Nuclear Information System (INIS)

Clemencic, M; Shapoval, I; Cattaneo, M; Degaudenzi, H; Santinelli, R

2012-01-01

The Conditions Database (CondDB) of the LHCb experiment provides versioned, time dependent geometry and conditions data for all LHCb data processing applications (simulation, high level trigger (HLT), reconstruction, analysis) in a heterogeneous computing environment ranging from user laptops to the HLT farm and the Grid. These different use cases impose front-end support for multiple database technologies (Oracle and SQLite are used). Sophisticated distribution tools are required to ensure timely and robust delivery of updates to all environments. The content of the database has to be managed to ensure that updates are internally consistent and externally compatible with multiple versions of the physics application software. In this paper we describe three systems that we have developed to address these issues. The first system is a CondDB state tracking extension to the Oracle 3D Streams replication technology, to trap cases when the CondDB replication was corrupted. Second, an automated distribution system for the SQLite-based CondDB, providing also smart backup and checkout mechanisms for the CondDB managers and LHCb users respectively. And, finally, a system to verify and monitor the internal (CondDB self-consistency) and external (LHCb physics software vs. CondDB) compatibility. The former two systems are used in production in the LHCb experiment and have achieved the desired goal of higher flexibility and robustness for the management and operation of the CondDB. The latter one has been fully designed and is passing currently to the implementation stage.

Attentional and visual demands for sprint performance in non-fatigued and fatigued conditions: reliability of a repeated sprint test

Directory of Open Access Journals (Sweden)

Diercks Ron L

2010-05-01

Full Text Available Abstract Background Physical performance measures are widely used to assess physical function, providing information about physiological and biomechanical aspects of motor performance. However they do not provide insight into the attentional and visual demands for motor performance. A figure-of-eight sprint test was therefore developed to measure the attentional and visual demands for repeated-sprint performance. The aims of the study were: 1 to assess test-retest reliability of the figure-of-eight sprint test, and 2 to study the attentional and visual demands for sprint performance in a non-fatigued and fatigued condition. Methods Twenty-seven healthy athletes were included in the study. To determine test-retest reliability, a subgroup of 19 athletes performed the figure-of-eight sprint test twice. The figure-of-eight sprint test consisted of nine 30-second sprints. The sprint test consisted of three test parts: sprinting without any restriction, with an attention-demanding task, and with restricted vision. Increases in sprint times with the attention-demanding task or restricted vision are reflective of the attentional and visual demands for sprinting. Intraclass correlation coefficients (ICCs and mean difference between test and retest with 95% confidence limits (CL were used to assess test-retest reliability. Repeated-measures ANOVA were used for comparisons between the sprint times and fatigue measurements of the test parts in both a non-fatigued and fatigued condition. Results The figure-of-eight sprint test showed good test-retest reliability, with ICCs ranging from 0.75 to 0.94 (95% CL: 0.40-0.98. Zero lay within the 95% CL of the mean differences, indicating that no bias existed between sprint performance at test and retest. Sprint times during the test parts with attention-demanding task (P = 0.01 and restricted vision (P Conclusions High ICCs and the absence of systematic variation indicate good test-retest reliability of the figure

4th International Conference on Condition Monitoring of Machinery in Non-Stationary Operations

CERN Document Server

Zimroz, Radoslaw; Bartelmus, Walter; Haddar, Mohamed

2016-01-01

The book provides readers with a snapshot of recent research and technological trends in the field of condition monitoring of machinery working under a broad range of operating conditions. Each chapter, accepted after a rigorous peer-review process, reports on an original piece of work presented and discussed at the 4th International Conference on Condition Monitoring of Machinery in Non-stationary Operations, CMMNO 2014, held on December 15-16, 2014, in Lyon, France. The contributions have been grouped into three different sections according to the main subfield (signal processing, data mining, or condition monitoring techniques) they are related to. The book includes both theoretical developments as well as a number of industrial case studies, in different areas including, but not limited to: noise and vibration; vibro-acoustic diagnosis; signal processing techniques; diagnostic data analysis; instantaneous speed identification; monitoring and diagnostic systems; and dynamic and fault modeling. This book no...

Single-photon detector operating under extremely high background photon flux conditions

International Nuclear Information System (INIS)

Prochazka, Ivan; Sopko, Bruno; Blazej, Josef

2009-01-01

We are reporting our results in research and development in the field of avalanche semiconductor single-photon detectors and their application. Our goal was a development of a solid-state photon-counting detector capable of high-precision photon arrival time tagging in extremely harsh operating conditions. The background photon flux exceeding 10 9 photons per second hitting the detector active area should not avoid the useful signal detection and recognition on the signal level of units of photons per second. This is background photon flux about two orders of magnitude higher than what the conventional solid-state photon counters accept. The detection timing resolution should be better than 100 ps and the delay stability should be on picosecond level. We have developed and tested the active quenched and gated avalanche structure on silicon providing the required features in connection with the K14 detection chips. The detector is capable of gated operation under the conditions of background photon flux of 5x10 9 photons per second. The operational detector tolerates long term exposures to the input photon flux exceeding 10 15 photons (>1 mW) per second without damage.

Safer operating conditions and optimal scaling-up process for cyclohexanone peroxide reaction

International Nuclear Information System (INIS)

Zang, Na; Qian, Xin-Ming; Liu, Zhen-Yi; Shu, Chi-Min

2015-01-01

Highlights: • Thermal hazard of cyclohexanone peroxide reaction was measured by experimental techniques. • Levenberg–Marquardt algorithm was adopted to evaluate kinetic parameters. • Safer operating conditions at laboratory scale were acquired by BDs and TDs. • The verified safer operating conditions were used to obtain the optimal scale-up parameters applied in industrial plants. - Abstract: The cyclohexanone peroxide reaction process, one of the eighteen hazardous chemical processes identified in China, is performed in indirectly cooled semibatch reactors. The peroxide reaction is added to a mixture of hydrogen peroxide and nitric acid, which form heterogeneous liquid–liquid systems. A simple and general procedure for building boundary and temperature diagrams of peroxide process is given here to account for the overall kinetic expressions. Such a procedure has been validated by comparison with experimental data. Thermally safer operating parameters were obtained at laboratory scale, and the scaled-up procedure was performed to give the minimum dosing time in an industrial plant, which is in favor of maximizing industrial reactor productivity. The results are of great significance for governing the peroxide reaction process apart from the thermal runaway region. It also greatly aids in determining optimization on operating parameters in industrial plants.

Optimal mode of operation for biomass production

NARCIS (Netherlands)

Betlem, Ben H.L.; Roffel, Brian; Mulder, P.

2002-01-01

The rate of biomass production is optimised for a predefined feed exhaustion using the residue ratio as a degree of freedom. Three modes of operation are considered: continuous, repeated batch, and repeated fed-batch operation. By means of the Production Curve, the transition points of the optimal

Effects of cathode channel size and operating conditions on the performance of air-blowing PEMFCs

International Nuclear Information System (INIS)

Kim, Bosung; Lee, Yongtaek; Woo, Ahyoung; Kim, Yongchan

2013-01-01

Highlights: • Effect of cathode channel size on the air-blowing PEMFC is analyzed. • Performance and EIS tests of air-blowing PEMFCs are conducted. • Test conditions include the operating temperature, fan voltage, and anode humidity. • Flooding is a limiting factor for decreasing channel size at low temperature. • Water management is investigated by analyzing ohmic resistance. - Abstract: Air-blowing proton exchange membrane fuel cells (PEMFCs) have been developed as a potential new power source for portable electronic devices. However, air-blowing PEMFCs show lower performance than compressed-air PEMFCs because of their adverse operating conditions. In this study, the effects of the cathode channel size and operating conditions on the performance of the air-blowing PEMFC were analyzed. At the normal operating temperature, the performance of the air-blowing PEMFC improved with the decrease in the cathode channel size. However, at a low operating temperature and low fan voltage, massive flooding limits the decrease in the cathode channel size. In addition, water management in the air-blowing PEMFC was investigated by analyzing ohmic resistance. The transition current density between the humidification and the flooding region decreased with decreasing cathode channel size and operating temperature

Matrix multiplication operations with data pre-conditioning in a high performance computing architecture

Science.gov (United States)

Eichenberger, Alexandre E; Gschwind, Michael K; Gunnels, John A

2013-11-05

Mechanisms for performing matrix multiplication operations with data pre-conditioning in a high performance computing architecture are provided. A vector load operation is performed to load a first vector operand of the matrix multiplication operation to a first target vector register. A load and splat operation is performed to load an element of a second vector operand and replicating the element to each of a plurality of elements of a second target vector register. A multiply add operation is performed on elements of the first target vector register and elements of the second target vector register to generate a partial product of the matrix multiplication operation. The partial product of the matrix multiplication operation is accumulated with other partial products of the matrix multiplication operation.

Repeated Exposure to Conditioned Fear Stress Increases Anxiety and Delays Sleep Recovery Following Exposure to an Acute Traumatic Stressor

OpenAIRE

Greenwood, Benjamin N.; Thompson, Robert S.; Opp, Mark R.; Fleshner, Monika

2014-01-01

Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep–wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the develo...

49 CFR 236.528 - Restrictive condition resulting from open hand-operated switch; requirement.

Science.gov (United States)

2010-10-01

... SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Rules and...-operated switch three-eighths inch or more, or hand-operated switch is not locked where facing point lock with circuit controller is used, the resultant restrictive condition of an automatic train stop or...

Optimisation of Shift Reactor Operating Conditions to Maximise Hydrogen Production

Energy Technology Data Exchange (ETDEWEB)

Sanchez, J. M.; Marano, M.; Ruiz, E.

2011-07-28

This report compiles the results of the work conducted by CIEMAT for Task 6.5 Shift reaction of the FLEXGAS project Near Zero Emission Advanced Fluidized Bed Gasification, which has been carried out with financial support from the Research Fund for Coal and Steel, RFCR-CT-2007-00005. The activity of an iron-chromium-based catalyst for the water gas shift reaction is studied. Results about WGS experiments conducted by CIEMAT on laboratory scale under different operating conditions are presented. The influence on the activity of the catalyst of main operating parameters- temperature, pressure, excess steam, and space velocity and gas composition - is evaluated and discussed. (Author) 19 refs.

Novel CO2 laser robotic controller outperforms experienced laser operators in tasks of accuracy and performance repeatability.

Science.gov (United States)

Wong, Yu-Tung; Finley, Charles C; Giallo, Joseph F; Buckmire, Robert A

2011-08-01

To introduce a novel method of combining robotics and the CO(2) laser micromanipulator to provide excellent precision and performance repeatability designed for surgical applications. Pilot feasibility study. We developed a portable robotic controller that appends to a standard CO(2) laser micromanipulator. The robotic accuracy and laser beam path repeatability were compared to six experienced users of the industry standard micromanipulator performing the same simulated surgical tasks. Helium-neon laser beam video tracking techniques were employed. The robotic controller demonstrated superiority over experienced human manual micromanipulator control in accuracy (laser path within 1 mm of idealized centerline), 97.42% (standard deviation [SD] 2.65%), versus 85.11% (SD 14.51%), P = .018; and laser beam path repeatability (area of laser path divergence on successive trials), 21.42 mm(2) (SD 4.35 mm(2) ) versus 65.84 mm(2) (SD 11.93 mm(2) ), P = .006. Robotic micromanipulator control enhances accuracy and repeatability for specific laser tasks. Computerized control opens opportunity for alternative user interfaces and additional safety features. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

How Repeated Time To Event (RTTE) modelling of opioid requests after surgery may improve future post-operative pain management

DEFF Research Database (Denmark)

Juul, Rasmus Vestergaard; Rasmussen, Sten; Kreilgaard, Mads

at Orthopaedic Department, Aalborg University Hospital, Denmark during the period May-Dec 2012. Morphine administration times (estimated precision: ±5mins), formulations and doses were extracted from medical journals in the hospitalization period or until 96 hours after surgery. RTTE modelling was performed......Title: How Repeated Time To Event (RTTE) modelling of opioid requests after surgery may improve future post-operative pain management Author: Rasmus Vestergaard Juul (1) Sten Rasmussen (2) Mads Kreilgaard (1) Ulrika S. H. Simonsson (3) Lona Louring Christrup (1) Trine Meldgaard Lund (1) Institution...... of surgery specific, drug concentration related, population specific and/or time-varying covariates of opioid requests and pain events. Conclusions: A framework has been developed based on RTTE modelling that may help improve future pain management by 1) Identification of surgery specific patterns in pain...

Repeat cesarean delivery: what indications are recorded in the medical chart?

Science.gov (United States)

Lydon-Rochelle, Mona T; Gardella, Carolyn; Cárdenas, Vicky; Easterling, Thomas R

2006-03-01

National surveillance estimates reported a troubling 63 percent decline in the rate of vaginal birth after cesarean delivery (VBAC) from 1996 (28.3%) to 2003 (10.6%), with subsequent rising rates of repeat cesarean delivery. The study objective was to examine patterns of documented indications for repeat cesarean delivery in women with and without labor. We conducted a population-based validation study of 19 nonfederal short-stay hospitals in Washington state. Of the 4,541 women who had live births in 2000, 11 percent (n = 493) had repeat cesarean without labor and 3 percent (n = 138) had repeat cesarean with labor. Incidence of medical conditions and pregnancy complications, patterns of documented indications for repeat cesarean delivery, and perioperative complications in relation to repeat cesarean delivery with and without labor were calculated. Of the 493 women who underwent a repeat cesarean delivery without labor, "elective"(36%) and "maternal request"(18%) were the most common indications. Indications for maternal medical conditions (3.0%) were uncommon. Among the 138 women with repeat cesarean delivery with labor, 60.1 percent had failure to progress, 24.6 percent a non-reassuring fetal heart rate, 8.0 percent cephalopelvic disproportion, and 7.2 percent maternal request during labor. Fetal indications were less common (5.8%). Breech, failed vacuum, abruptio placentae, maternal complications, and failed forceps were all indicated less than 5.0 percent. Women's perioperative complications did not vary significantly between women without and with labor. Regardless of a woman's labor status, nearly 10 percent of women with repeat cesarean delivery had no documented indication as to why a cesarean delivery was performed. "Elective" and "maternal request" were common indications among women undergoing repeat cesarean delivery without labor, and nearly 10 percent of women had undocumented indications for repeat cesarean delivery in their medical record

Exergy characteristics of a ceiling-type residential air conditioning system operating under different climatic conditions

Energy Technology Data Exchange (ETDEWEB)

Ozbek, Arif [Dept. of Mechanical Engineering, Ceyhan Engineering Faculty, Cukurova University, Adana (Turkmenistan)

2016-11-15

In this study an energy and exergy analysis of a Ceiling-type residential air conditioning (CTRAC) system operating under different climatic conditions have been investigated for provinces within the different geographic regions of Turkey. Primarily, the hourly cooling load capacities of a sample building (Q{sub evap}) during the months of April, May, June, July, August and September were determined. The hourly total heat gain of the sample building was determined using the Hourly analysis program (HAP). The Coefficient of performance (COP), exergy efficiency (η) and exergy destruction (Ex{sub dest}) values for the whole system and for each component were obtained. The results showed that lower atmospheric temperature (T{sub atm}) influenced the performance of the system and each of its components.

How Much of Language Acquisition Does Operant Conditioning Explain?

OpenAIRE

Sturdy, Christopher B.; Nicoladis, Elena

2017-01-01

Since the 1950s, when Chomsky argued that Skinner’s arguments could not explain syntactic acquisition, psychologists have generally avoided explicitly invoking operant or instrumental conditioning as a learning mechanism for language among human children. In this article, we argue that this is a mistake. We focus on research that has been done on language learning in human infants and toddlers in order to illustrate our points. Researchers have ended up inventing learning mechanisms that, in ...

Long-term effects of repeated social stress on the conditioned place preference induced by MDMA in mice.

Science.gov (United States)

García-Pardo, M P; Blanco-Gandía, M C; Valiente-Lluch, M; Rodríguez-Arias, M; Miñarro, J; Aguilar, M A

2015-12-03

Previous studies have demonstrated that social defeat stress increases the rewarding effects of psychostimulant drugs such as cocaine and amphetamine. In the present study we evaluated the long-term effects of repeated social defeat (RSD) on the rewarding effects of ±3,4-methylenedioxymethamphetamine (MDMA) hydrochloride in the conditioned place preference (CPP) paradigm. Adolescent and young adult mice were exposed to four episodes of social defeat (on PND 29-40 and PND 47-56, respectively) and were conditioned three weeks later with 1.25 or 10mg/kg i.p. of MDMA (experiment 1). The long-term effects of RSD on anxiety, social behavior and cognitive processes were also evaluated in adult mice (experiment 2). RSD during adolescence enhanced vulnerability to priming-induced reinstatement in animals conditioned with 1.25mg/kg of MDMA and increased the duration of the CPP induced by the 10mg/kg of MDMA. The latter effect was also observed after RSD in young adult mice, as well as an increase in anxiety-like behavior, an alteration in social interaction (reduction in attack and increase in avoidance/flee and defensive/submissive behaviors) and an impairment of maze learning. These results support the idea that RSD stress increases the rewarding effects of MDMA and induces long-term alterations in anxiety, learning and social behavior in adult mice. Thus, exposure to stress may increase the vulnerability of individuals to developing MDMA dependence, which is a factor to be taken into account in relation to the prevention and treatment of this disorder. Copyright © 2015 Elsevier Inc. All rights reserved.

Experimental Analysis for Factors Affecting the Repeatability of Plastics Injection Molding Tests on the Self-developed Apparatus

Directory of Open Access Journals (Sweden)

Yugang Huang

2013-06-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 To improve the repeatability of the injection molding test result, the affecting factors were investigated by means of experiments. Besides the traditional processing parameter, the factors of test conditions were also considered. In order to focus on the molding process rather than the molded part, the curve measurement of the melt pressure at the entrance to the nozzle was used as the output characteristic. Experiments for polypropylene (PP showed that the injected volume was the key processing parameter. Within the test conditions, the injection number is the most important factor. According to the analysis the operating procedure was improved effectively. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Doi: 10.12777/ijse.5.1.6-11 [How to cite this article: Huang, Y., Li, D., Liu, Y. (2013. Experimental Analysis for Factors Affecting the Repeatability of Plastics Injection Molding Tests on the Self-developed Apparatus. International Journal of Science and Engineering, 5(1,6-11. Doi: 10.12777/ijse.5.1.6-11]

Thermal behaviour of fuel: influence on the behavior of fuel elements in nominal and incidental operating conditions

International Nuclear Information System (INIS)

Languille, A.

1984-02-01

The behaviour of the oxide, in normal conditions as well as in incidental conditions is an important care at the fuel element design level in a fast reactor. In nominal operating conditions, the probability of melt to core of the pellet is very low and even for high burnup. The behaviour in incidental operating conditions is also satisfying, especially for inadvertent rod ejections [fr

Experimental and simulational study of the operation conditions for a high transmission mass filter

International Nuclear Information System (INIS)

Ayesh, A. I.; Lassesson, A.; Brown, S. A.; Dunbar, A. D. F.; Kaufmann, M.; Partridge, J. G.; Reichel, R.; Lith, J. van

2007-01-01

The operation conditions of a double pulsed field mass filter were studied using both experiment and simulation. The mass filter consists of two pairs of parallel plates and operates on the time-of-flight principle. The study showed that the ions' beam deflection angle is a critical factor in optimizing the mass filter transmission efficiency. This angle is dependent on the accelerating voltage, ion mass, and horizontal velocity of the ions. The optimum operating conditions for the mass filter were found and used to study the mass distribution of palladium ions produced by a magnetron sputtering source. The study shows that this mass filter is suitable for technological applications because of its high transmission and wide mass range

Application of signature analysis for determining the operational readiness of motor-operated valves under blowdown test conditions

International Nuclear Information System (INIS)

Haynes, H.D.

1990-01-01

In support of the NRC-funded Nuclear Plant Aging Research (NPAR) program, Oak Ridge National Laboratory (ORNL) has carried out a comprehensive aging assessment of motor-operated valves (MOVs). As part of this work, ORNL participated in the gate valve flow interrruption blowdown (GVFIB) tests carried out in Huntsville, Alabama. The tests provided an excellent opportunity to evaluate signature analysis methods for determining the operability of MOVs under accident conditions. ORNL acquired motor current and torque switch shaft angular position signatures on two test MOVs during several GVFIB tests. The reduction in operating ''margin'' of both MOVs due to the presence of additional valve running loads imposed by high flow was clearly observed in motor current and torque switch angular position signatures. In addition, the effects of differential pressure, fluid temperature, and line voltage on MOV operations were observed and more clearly understood as a result of utilizing the signature analysis techniques. (orig.)

Regularization in Hilbert space under unbounded operators and general source conditions

International Nuclear Information System (INIS)

Hofmann, Bernd; Mathé, Peter; Von Weizsäcker, Heinrich

2009-01-01

The authors study ill-posed equations with unbounded operators in Hilbert space. This setup has important applications, but only a few theoretical studies are available. First, the question is addressed and answered whether every element satisfies some general source condition with respect to a given self-adjoint unbounded operator. This generalizes a previous result from Mathé and Hofmann (2008 Inverse Problems 24 015009). The analysis then proceeds to error bounds for regularization, emphasizing some specific points for regularization under unbounded operators. The study finally reviews two examples within the light of the present study, as these are fractional differentiation and some Cauchy problems for the Helmholtz equation, both studied previously and in more detail by U Tautenhahn and co-authors

Condition Monitoring for Roller Bearings of Wind Turbines Based on Health Evaluation under Variable Operating States

Directory of Open Access Journals (Sweden)

Lei Fu

2017-10-01

Full Text Available Condition monitoring (CM is used to assess the health status of wind turbines (WT by detecting turbine failure and predicting maintenance needs. However, fluctuating operating conditions cause variations in monitored features, therefore increasing the difficulty of CM, for example, the frequency-domain analysis may lead to an inaccurate or even incorrect prediction when evaluating the health of the WT components. In light of this challenge, this paper proposed a method for the health evaluation of WT components based on vibration signals. The proposed approach aimed to reduce the evaluation error caused by the impact of the variable operating condition. First, the vibration signal was decomposed into a set of sub-signals using variational mode decomposition (VMD. Next, the sub-signal energy and the probability distribution were obtained and normalized. Finally, the concept of entropy was introduced to evaluate the health condition of a monitored object to provide an effective guide for maintenance. In particular, the health evaluation for CM was based on a performance review over a range of operating conditions, rather than at a certain single operating condition. Experimental investigations were performed which verified the efficiency of the evaluation method, as well as a comparison with the previous method.

Mechanical stress analysis for a fuel rod under normal operating conditions

International Nuclear Information System (INIS)

Pino, Eddy S.; Giovedi, Claudia; Serra, Andre da Silva; Abe, Alfredo Y.

2013-01-01

Nuclear reactor fuel elements consist mainly in a system of a nuclear fuel encapsulated by a cladding material subject to high fluxes of energetic neutrons, high operating temperatures, pressure systems, thermal gradients, heat fluxes and with chemical compatibility with the reactor coolant. The design of a nuclear reactor requires, among a set of activities, the evaluation of the structural integrity of the fuel rod submitted to different loads acting on the fuel rod and the specific properties (dimensions and mechanical and thermal properties) of the cladding material and coolant, including thermal and pressure gradients produced inside the rod due to the fuel burnup. In this work were evaluated the structural mechanical stresses of a fuel rod using stainless steel as cladding material and UO 2 with a low degree of enrichment as fuel pellet on a PWR (pressurized water reactor) under normal operating conditions. In this sense, tangential, radial and axial stress on internal and external cladding surfaces considering the orientations of 0 deg, 90 deg and 180 deg were considered. The obtained values were compared with the limit values for stress to the studied material. From the obtained results, it was possible to conclude that, under the expected normal reactor operation conditions, the integrity of the fuel rod can be maintained. (author)

CFD analysis of a full-scale ceramic kiln module under actual operating conditions

Science.gov (United States)

Milani, Massimo; Montorsi, Luca; Stefani, Matteo; Venturelli, Matteo

2017-11-01

The paper focuses on the CFD analysis of a full-scale module of an industrial ceramic kiln under actual operating conditions. The multi-dimensional analysis includes the real geometry of a ceramic kiln module employed in the preheating and firing sections and investigates the heat transfer between the tiles and the burners' flame as well as the many components that comprise the module. Particular attention is devoted to the simulation of the convective flow field in the upper and lower chambers and to the effects of radiation on the different materials is addressed. The assessment of the radiation contribution to the tiles temperature is paramount to the improvement of the performance of the kiln in terms of energy efficiency and fuel consumption. The CFD analysis is combined to a lumped and distributed parameter model of the entire kiln in order to simulate the module behaviour at the boundaries under actual operating conditions. Finally, the CFD simulation is employed to address the effects of the module operating conditions on the tiles' temperature distribution in order to improve the temperature uniformity as well as to enhance the energy efficiency of the system and thus to reduce the fuel consumption.

Operating conditions of the BPX divertor

International Nuclear Information System (INIS)

Hill, D.N.; Milovich, J.; Rognlien, T.; Braams, B.J.; Brooks, J.N.; Campbell, R.; Haines, J.; Knoll, D.; Prinja, A.; Stotler, D.P.; Ulrickson, M.

1991-01-01

In this paper we discuss the expected operating conditions at the divertor of the BPX tokamak (Burning Plasma Experiment), the next- step US tokamak proposed for the study of self-heated plasmas at Q ≅ 5 to ignition. In this double-null device (κ ≅ 2), the predicted first-wall loading is high because of is compact size (R = 2.6m, α = 0.8m, I p = 10.6 MA, and B T ) and its high projected fusion power output (100--500 MW with up to 20 MW of ICRH). Present designs call for inertially cooled carbon-based target plate material and X-point sweeping to handle the divertor heat flux during the 3--5 s flat-top at full power. The X-point is maintained about 15--20 cm off the target plates (a distance of ∼5m along field lines), which represents a reasonable compromise between lowering the divertor electron temperature (T e,d ) by increasing the connection length, and lowering the peak divertor heat flux (q d ) by increasing the magnetic flux expansion (which is about 15--20 in this case). It is planned for the BPX device to operate with H-mode confinement; ELMs are expected because of the relatively high power flow through the edge plasma (P sep ≅ 0.6 MW/m 2 for P fus = 500 MW). The ELMs will help reduce the impurity concentration in the core plasma (Z eff ≅ 1.7) and keep the density down, but should not add significantly to the divertor heat flux since their measured contribution to the global power balance drops with increasing input power

Repeated Induction of Inattentional Blindness in a Simulated Aviation Environment

Science.gov (United States)

Kennedy, Kellie D.; Stephens, Chad L.; Williams, Ralph A.; Schutte, Paul C.

2017-01-01

The study reported herein is a subset of a larger investigation on the role of automation in the context of the flight deck and used a fixed-based, human-in-the-loop simulator. This paper explored the relationship between automation and inattentional blindness (IB) occurrences in a repeated induction paradigm using two types of runway incursions. The critical stimuli for both runway incursions were directly relevant to primary task performance. Sixty non-pilot participants performed the final five minutes of a landing scenario twice in one of three automation conditions: full automation (FA), partial automation (PA), and no automation (NA). The first induction resulted in a 70 percent (42 of 60) detection failure rate with those in the PA condition significantly more likely to detect the incursion compared to the FA condition or the NA condition. The second induction yielded a 50 percent detection failure rate. Although detection improved (detection failure rates declined) in all conditions, those in the FA condition demonstrated the greatest improvement with doubled detection rates. The detection behavior in the first trial did not preclude a failed detection in the second induction. Group membership (IB vs. Detection) in the FA condition showed a greater improvement than those in the NA condition and rated the Mental Demand and Effort subscales of the NASA-TLX (NASA Task Load Index) significantly higher for Time 2 compared Time 1. Participants in the FA condition used the experience of IB exposure to improve task performance whereas those in the NA condition did not, indicating the availability and reallocation of attentional resources in the FA condition. These findings support the role of engagement in operational attention detriment and the consideration of attentional failure causation to determine appropriate mitigation strategies.

Acquiring a cognitive skill with a new repeating version of the Tower of London task.

Science.gov (United States)

Ouellet, Marie-Christine; Beauchamp, Miriam H; Owen, Adrian M; Doyon, Julien

2004-12-01

A computerized version of the Tower of London task was used to investigate cognitive skill learning. Thirty-six healthy volunteers were assigned to either a random condition (nonrecurring problems), or to a sequence condition in which, unbeknownst to the subjects, a repeating sequence of three problems was presented. Indices of execution, planning, and total time, as well as number of moves performed, were used to measure behavioural change. Subjects' performance improved in both conditions across blocks of practice. A distinct learning effect related to the repeating sequence was also observed. This suggests that a specific skill that reflects procedural learning of the strategies, rules, and procedures pertaining to repeating problems can develop over and above a more general skill at solving cognitive planning problems with practice.

Visual perceptual learning by operant conditioning training follows rules of contingency

Science.gov (United States)

Kim, Dongho; Seitz, Aaron R; Watanabe, Takeo

2015-01-01

Visual perceptual learning (VPL) can occur as a result of a repetitive stimulus-reward pairing in the absence of any task. This suggests that rules that guide Conditioning, such as stimulus-reward contingency (e.g. that stimulus predicts the likelihood of reward), may also guide the formation of VPL. To address this question, we trained subjects with an operant conditioning task in which there were contingencies between the response to one of three orientations and the presence of reward. Results showed that VPL only occurred for positive contingencies, but not for neutral or negative contingencies. These results suggest that the formation of VPL is influenced by similar rules that guide the process of Conditioning. PMID:26028984

Visual perceptual learning by operant conditioning training follows rules of contingency.

Science.gov (United States)

Kim, Dongho; Seitz, Aaron R; Watanabe, Takeo

2015-01-01

Visual perceptual learning (VPL) can occur as a result of a repetitive stimulus-reward pairing in the absence of any task. This suggests that rules that guide Conditioning, such as stimulus-reward contingency (e.g. that stimulus predicts the likelihood of reward), may also guide the formation of VPL. To address this question, we trained subjects with an operant conditioning task in which there were contingencies between the response to one of three orientations and the presence of reward. Results showed that VPL only occurred for positive contingencies, but not for neutral or negative contingencies. These results suggest that the formation of VPL is influenced by similar rules that guide the process of Conditioning.

Repeating and non-repeating fast radio bursts from binary neutron star mergers

Science.gov (United States)

Yamasaki, Shotaro; Totani, Tomonori; Kiuchi, Kenta

2018-04-01

Most fast radio bursts (FRB) do not show evidence of repetition, and such non-repeating FRBs may be produced at the time of a merger of binary neutron stars (BNS), provided that the BNS merger rate is close to the high end of the currently possible range. However, the merger environment is polluted by dynamical ejecta, which may prohibit the radio signal from propagating. We examine this by using a general-relativistic simulation of a BNS merger, and show that the ejecta appears about 1 ms after the rotation speed of the merged star becomes the maximum. Therefore there is a time window in which an FRB signal can reach outside, and the short duration of non-repeating FRBs can be explained by screening after ejecta formation. A fraction of BNS mergers may leave a rapidly rotating and stable neutron star, and such objects may be the origin of repeating FRBs like FRB 121102. We show that a merger remnant would appear as a repeating FRB on a time scale of ˜1-10 yr, and expected properties are consistent with the observations of FRB 121102. We construct an FRB rate evolution model that includes these two populations of repeating and non-repeating FRBs from BNS mergers, and show that the detection rate of repeating FRBs relative to non-repeating ones rapidly increases with improving search sensitivity. This may explain why only the repeating FRB 121102 was discovered by the most sensitive FRB search with Arecibo. Several predictions are made, including the appearance of a repeating FRB 1-10 yr after a BNS merger that is localized by gravitational waves and subsequent electromagnetic radiation.

Appetitive operant conditioning in mice: heritability and dissociability of training stages

NARCIS (Netherlands)

Malkki, H.A.I.; Donga, L.A.B.; de Groot, S.E.; Battaglia, F.P.; Brussaard, A.B.; Borst, J.G.G.; Elgersma, Y.; Galjart, N.; van der Horst, G.T.; Levelt, C.N.; Pennartz, C.M.A.; Smit, A.B.; Spruijt, B.M.; Verhage, M.; de Zeeuw, C.I.

2010-01-01

To study the heritability of different training stages of appetitive operant conditioning, we carried out behavioral screening of 5 standard inbred mouse strains, 28 recombinant-inbred (BxD) mouse lines and their progenitor strains C57BL/6J and DBA/2J. We also computed correlations between

Sealing of rotary drums for operation under pressurized conditions

International Nuclear Information System (INIS)

Shirvani, M.; Khanof, M. H.; Yousefi, M. R.; Sadighi, S.

2006-01-01

In practice, rotary drums are always designed for operation under vacuum conditions. In this paper, a novel technique is proposed for sealing the rotary drums under pressurized conditions. The proposed system is based on applying a secondary pressurized volume around the leaking gap of the drum. By controlling the pressure of this volume above the pressure of the drum, it will be possible to prevent from any leakage of gases to the ambient. The objective of a controller in this system is that the pressure of secondary volume be kept above the pressure of the drum in spite of the disturbances which may be exerted on the system by the wind outside the drum. The control system is also required to trace the variations in the drum pressure with the least fluctuations in the pressure difference among the drum and the volume

Advantages and disadvantages : longitudinal vs. repeated cross-section surveys

Science.gov (United States)

1996-06-20

The benefits of a longitudinal analysis over a repeated cross-sectional study include increased statistical power and the capability to estimate a greater range of conditional probabilities. With the Puget Sound Transportation Panel (PSTP), and any s...

Repeated Recall and PKM? Maintain Fear Memories in Juvenile Rats

Science.gov (United States)

Oliver, Chicora F.; Kabitzke, Patricia; Serrano, Peter; Egan, Laura J.; Barr, Gordon A.; Shair, Harry N.; Wiedenmayer, Christoph

2016-01-01

We examined the neural substrates of fear memory formation and maintenance when repeated recall was used to prevent forgetting in young animals. In contrast to adult rats, juveniles failed to show contextual fear responses at 4 d post-fear conditioning. Reconsolidation sessions 3 and 6 d after conditioning restored contextual fear responses in…

Dioxins from medical waste incineration: Normal operation and transient conditions.

Science.gov (United States)

Chen, Tong; Zhan, Ming-xiu; Yan, Mi; Fu, Jian-ying; Lu, Sheng-yong; Li, Xiao-dong; Yan, Jian-hua; Buekens, Alfons

2015-07-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are key pollutants in waste incineration. At present, incinerator managers and official supervisors focus only on emissions evolving during steady-state operation. Yet, these emissions may considerably be raised during periods of poor combustion, plant shutdown, and especially when starting-up from cold. Until now there were no data on transient emissions from medical (or hospital) waste incineration (MWI). However, MWI is reputed to engender higher emissions than those from municipal solid waste incineration (MSWI). The emission levels in this study recorded for shutdown and start-up, however, were significantly higher: 483 ± 184 ng Nm(-3) (1.47 ± 0.17 ng I-TEQ Nm(-3)) for shutdown and 735 ng Nm(-3) (7.73 ng I-TEQ Nm(-3)) for start-up conditions, respectively. Thus, the average (I-TEQ) concentration during shutdown is 2.6 (3.8) times higher than the average concentration during normal operation, and the average (I-TEQ) concentration during start-up is 4.0 (almost 20) times higher. So monitoring should cover the entire incineration cycle, including start-up, operation and shutdown, rather than optimised operation only. This suggestion is important for medical waste incinerators, as these facilities frequently start up and shut down, because of their small size, or of lacking waste supply. Forthcoming operation should shift towards much longer operating cycles, i.e., a single weekly start-up and shutdown. © The Author(s) 2015.

Studies on Section XI ultrasonic repeatability

International Nuclear Information System (INIS)

Jamison, T.D.; McDearman, W.R.

1981-05-01

A block representative of a nuclear component has been welded containing intentional defects. Acoustic emission data taken during the welding correlate well with ultrasonic data. Repetitive ultrasonic examinations have been performed by skilled operators using a procedure based on that desribed in ASME Section XI. These examinations were performed by different examination teams using different ultrasonic equipment in such a manner that the effects on the repeatability of the ultrasonic test method caused by the operator and by the use of different equipment could be estimated. It was tentatively concluded that when considering a large number of inspections: (1) there is no significant difference in indication sizing between operators, and (2) there is a significant difference in amplitude and defect sizing when instruments having different, Code acceptable operating characteristics are used. It was determined that the Section XI sizing parameters follow a bivariate normal distribution. Data derived from ultrasonically and physically sizing indications in nuclear components during farication show that the Section XI technique tends to overestimate the size of the reflectors

The one-sided Ap conditions and local maximal operator

Czech Academy of Sciences Publication Activity Database

Bernardis, A.L.; Gogatishvili, Amiran; Martin-Reyes, F. J.; Ortega Salvador, P.; Pick, L.

Roč. 55, č. 1 ( 2012 ), s. 79-104 ISSN 0013-0915 R&D Projects: GA ČR GA201/08/0383; GA ČR GA201/05/2033 Institutional research plan: CEZ:AV0Z10190503 Keywords : one-sided Ap conditions * one-sided local maximal operator * quasi-Banach function spaces * variable-exponent Lebesgue spaces Subject RIV: BA - General Mathematics Impact factor: 0.561, year: 2012 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8477114&fulltextType=RA&fileId=S0013091510000635

The effects of overtime work and task complexity on the performance of nuclear plant operators: A proposed methodology

International Nuclear Information System (INIS)

Banks, W.W.; Potash, L.

1985-01-01

This document presents a very general methodology for determining the effect of overtime work and task complexity on operator performance in response to simulated out-of-limit nuclear plant conditions. The independent variables consist of three levels of overtime work and three levels of task complexity. Multiple dependent performance measures are proposed for use and discussion. Overtime work is operationally defined in terms of the number of hours worked by nuclear plant operators beyond the traditional 8 hours per shift. Task complexity is operationalized in terms of the number of operator tasks required to remedy a given plant anomalous condition and bring the plant back to a ''within limits'' or ''normal'' steady-state condition. The proposed methodology would employ a 2 factor repeated measures design along with the analysis of variance (linear) model

Substantial-Motivational Mechanism for Substantiation of Tolling Operations in Conditions of the European Integration

OpenAIRE

Melnyk Olga G; Kots Iryna I.

2016-01-01

The article is concerned with conceptualization of substance, distinguishing characteristics and motives of the implementation of tolling operations in conditions of the European integration. The study, based on the systematization and analysis of existing scientific approaches to definition of essence of tolling and tolling operations, has disclosed the dominating poli-positionality and ambiguity in this area. Economical autonomy of tolling operations has been determined, t...

Optimum Operating Conditions for PZT Actuators for Vibrotactile Wearables

Science.gov (United States)

Logothetis, Irini; Matsouka, Dimitra; Vassiliadis, Savvas; Vossou, Clio; Siores, Elias

2018-04-01

Recently, vibrotactile wearables have received much attention in fields such as medicine, psychology, athletics and video gaming. The electrical components presently used to generate vibration are rigid; hence, the design and creation of ergonomical wearables are limited. Significant advances in piezoelectric components have led to the production of flexible actuators such as piezoceramic lead zirconate titanate (PZT) film. To verify the functionality of PZT actuators for use in vibrotactile wearables, the factors influencing the electromechanical conversion were analysed and tested. This was achieved through theoretical and experimental analyses of a monomorph clamped-free structure for the PZT actuator. The research performed for this article is a three-step process. First, a theoretical analysis presents the equations governing the actuator. In addition, the eigenfrequency of the film was analysed preceding the experimental section. For this stage, by applying an electric voltage and varying the stimulating electrical characteristics (i.e., voltage, electrical waveform and frequency), the optimum operating conditions for a PZT film were determined. The tip displacement was measured referring to the mechanical energy converted from electrical energy. From the results obtained, an equation for the mechanical behaviour of PZT films as actuators was deduced. It was observed that the square waveform generated larger tip displacements. In conjunction with large voltage inputs at the predetermined eigenfrequency, the optimum operating conditions for the actuator were achieved. To conclude, PZT films can be adapted to assist designers in creating comfortable vibrotactile wearables.

Optimization of the operating conditions of gas-turbine power stations considering the effect of equipment deterioration

Science.gov (United States)

Aminov, R. Z.; Kozhevnikov, A. I.

2017-10-01

In recent years in most power systems all over the world, a trend towards the growing nonuniformity of energy consumption and generation schedules has been observed. The increase in the portion of renewable energy sources is one of the important challenges for many countries. The ill-predictable character of such energy sources necessitates a search for practical solutions. Presently, the most efficient method for compensating for nonuniform generation of the electric power by the renewable energy sources—predominantly by the wind and solar energy—is generation of power at conventional fossil-fuel-fired power stations. In Russia, this problem is caused by the increasing portion in the generating capacity structure of the nuclear power stations, which are most efficient when operating under basic conditions. Introduction of hydropower and pumped storage hydroelectric power plants and other energy-storage technologies does not cover the demand for load-following power capacities. Owing to a simple design, low construction costs, and a sufficiently high economic efficiency, gas turbine plants (GTPs) prove to be the most suitable for covering the nonuniform electric-demand schedules. However, when the gas turbines are operated under varying duty conditions, the lifetime of the primary thermostressed components is considerably reduced and, consequently, the repair costs increase. A method is proposed for determination of the total operating costs considering the deterioration of the gas turbine equipment under varying duty and start-stop conditions. A methodology for optimization of the loading modes for the gas turbine equipment is developed. The consideration of the lifetime component allows varying the optimal operating conditions and, in some cases, rejecting short-time stops of the gas turbine plants. The calculations performed in a wide range of varying fuel prices and capital investments per gas turbine equipment unit show that the economic effectiveness can

The optimum operating conditions of the phased double-rotor facility at the ET-RR-1 reactor

Energy Technology Data Exchange (ETDEWEB)

Naguib, K.; Habib, N.; Wahba, M.; Kilany, M.; Adib, M. [National Research Centre, Cairo (Egypt). Reactor and Neutron Physics Dept.

1997-02-07

A pulsed neutron polyenergetic thermal beam at ET-RR-1 is produced by a phased double-rotor facility. One of the rotors has two diametrically opposite curved slots, while the second is designed to operate as a rotating collimator. The dimensions of the phased rotating collimator are selected to match the curved slot rotor. The calculated collimator transmissions at different operating conditions are found to be in good agreement with the experimental ones. The optimum operating conditions of the double-rotor facility are deduced. The calculations were carried out using a computer program RCOL. The RCOL was designed in FORTRAN-77 to operate on PCs. (author).

The optimum operating conditions of the phased double-rotor facility at the ET-RR-1 reactor

International Nuclear Information System (INIS)

Naguib, K.; Habib, N.; Wahba, M.; Kilany, M.; Adib, M.

1997-01-01

A pulsed neutron polyenergetic thermal beam at ET-RR-1 is produced by a phased double-rotor facility. One of the rotors has two diametrically opposite curved slots, while the second is designed to operate as a rotating collimator. The dimensions of the phased rotating collimator are selected to match the curved slot rotor. The calculated collimator transmissions at different operating conditions are found to be in good agreement with the experimental ones. The optimum operating conditions of the double-rotor facility are deduced. The calculations were carried out using a computer program RCOL. The RCOL was designed in FORTRAN-77 to operate on PCs. (author)

The effects of system configuration and operating condition on the MCFC system efficiency

Energy Technology Data Exchange (ETDEWEB)

Kang, B.S. [Korea Electric Power Research Institute, Taejeon (Korea)

2001-07-01

The process simulation model of an externally reformed molten carbonate fuel cell (MCFC) system is used to analyze quantitatively the parametric effect on the system efficiency. In order to verify the MCFC process simulation model, the 25-kW system was analyzed on the basis of the experimental data and its calculated efficiency showed reasonable. The overall system efficiency of high-temperature fuel cell system, especially MCFC, can not be increased without the proper thermal integration between heat recovery units and additional power generation from auxiliary power generating units such as turbines. The simulation results show that the configuration of unit operators in a given system has great effect on the system efficiency while the system size and operating condition have slightly lower effect on it. Based on the system configuration, optimal operating condition including fuel, oxidant utilization, and recycle ratio can be specified to maximize the system efficiency. (author). 12 refs., 10 figs., 2 tabs.

Distribution of AC loss in a HTS magnet for SMES with different operating conditions

Energy Technology Data Exchange (ETDEWEB)

Xu, Y., E-mail: xuyinghust@163.com [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Tang, Y.; Ren, L.; Jiao, F. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Song, M.; Cao, K.; Wang, D. [Yunnan Electric Power Research Institute, Kunming City 650217 (China); Wang, L.; Dong, H. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China)

2013-11-15

Highlights: •We present a model to calculate the distribution of AC loss for a storage magnet. •Comparative analysis of AC loss with different operating conditions has done. •The nonuniform distribution factor “d” is proposed to estimate the inhomogeneity of a storage magnet. •The model predicts the loss distribution and crucial areas which are suffering from the high AC loss. This is significant for the conduction-cooled structure design. -- Abstract: The AC loss induced in superconducting tape may affect the performance of a superconducting device applied to power system, such as transformer, cable, motor and even Superconducting Magnetic Energy Storage (SMES). The operating condition of SMES is changeable due to the need of compensation to the active or reactive power according to the demand of a power grid. In this paper, it is investigated that the distribution of AC loss for a storage magnet on different operating conditions, which is based on finite element method (FEM) and measured properties of BSCCO/Ag tapes. This analytical method can be used to optimize the SMES magnet.

Operant conditioning of enhanced pain sensitivity by heat-pain titration.

Science.gov (United States)

Becker, Susanne; Kleinböhl, Dieter; Klossika, Iris; Hölzl, Rupert

2008-11-15

Operant conditioning mechanisms have been demonstrated to be important in the development of chronic pain. Most experimental studies have investigated the operant modulation of verbal pain reports with extrinsic reinforcement, such as verbal reinforcement. Whether this reflects actual changes in the subjective experience of the nociceptive stimulus remained unclear. This study replicates and extends our previous demonstration that enhanced pain sensitivity to prolonged heat-pain stimulation could be learned in healthy participants through intrinsic reinforcement (contingent changes in nociceptive input) independent of verbal pain reports. In addition, we examine whether different magnitudes of reinforcement differentially enhance pain sensitivity using an operant heat-pain titration paradigm. It is based on the previously developed non-verbal behavioral discrimination task for the assessment of sensitization, which uses discriminative down- or up-regulation of stimulus temperatures in response to changes in subjective intensity. In operant heat-pain titration, this discriminative behavior and not verbal pain report was contingently reinforced or punished by acute decreases or increases in heat-pain intensity. The magnitude of reinforcement was varied between three groups: low (N1=13), medium (N2=11) and high reinforcement (N3=12). Continuous reinforcement was applied to acquire and train the operant behavior, followed by partial reinforcement to analyze the underlying learning mechanisms. Results demonstrated that sensitization to prolonged heat-pain stimulation was enhanced by operant learning within 1h. The extent of sensitization was directly dependent on the received magnitude of reinforcement. Thus, operant learning mechanisms based on intrinsic reinforcement may provide an explanation for the gradual development of sustained hypersensitivity during pain that is becoming chronic.

On Operating a Nanofiltration Membrane for Olive Mill Wastewater Purification at Sub- and Super-Boundary Conditions.

Science.gov (United States)

Stoller, Marco; Ochando-Pulido, Javier Miguel; Field, Robert

2017-07-14

In the last decades, membrane processes have gained a significant share of the market for wastewater purification. Although the product (i.e., purified water) is not of high added value, these processes are feasible both technically and from an economic point of view, provided the flux is relatively high and that membrane fouling is strongly inhibited. By controlling membrane fouling, the membrane may work for years without service, thus dramatically reducing operating costs and the need for membrane substitution. There is tension between operating at high permeate fluxes, which enhances fouling but reduces capital costs, and operating at lower fluxes which increases capital costs. Operating batch membrane processes leads to increased difficulties, since the feed fed to the membrane changes as a function of the recovery value. This paper is concerned with the operation of such a process. Membrane process designers should therefore avoid membrane fouling by operating membranes away from the permeate flux point where severe fouling is triggered. The design and operation of membrane purification plants is a difficult task, and the precision to properly describe the evolution of the fouling phenomenon as a function of the operating conditions is a key to success. Many reported works have reported on the control of fouling by operating below the boundary flux. On the other hand, only a few works have successfully sought to exploit super-boundary operating conditions; most super-boundary operations are reported to have led to process failures. In this work, both sub- and super-boundary operating conditions for a batch nanofiltration membrane process used for olive mill wastewater treatment were investigated. A model to identify a priori the point of transition from a sub-boundary to a super-boundary operation during a batch operation was developed, and this will provide membrane designers with a helpful tool to carefully avoid process failures.

Technical Condition of Earthen Dams at Nizhegorodskaya HPP After 60 Years of Operation

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, V. S., E-mail: kuznetsovVS@vniig.ru; Ladenko, S. Yu., E-mail: ladenko@yandex.ru [B. E. Vedeneev All-Russian Research Institute of Hydraulic Engineering (JSC) (Russian Federation)

2016-03-15

The complex of hydraulic engineering installations includes five earthen dams. All facilities are of Class I. The diagnostic parameters of dam operation and technical condition monitored via in-situ observation for seepage mode, seepage strength, settlement, static stability, etc. generally meet design assumptions and safety criteria. Despite individual defects and signs of “aging” identified over the period of earthen dam operation, these are currently in a satisfactory and operable state. The long, 60-year operating period of the dams with no serious overhauls or emergencies has demonstrated the high reliability of the facilities, the correctness of the design and technological solutions adopted and implemented in the construction, and the high professional level of their operation in close cooperation with science.

Operant Conditioning in Honey Bees (Apis mellifera L.): The Cap Pushing Response.

Science.gov (United States)

Abramson, Charles I; Dinges, Christopher W; Wells, Harrington

2016-01-01

The honey bee has been an important model organism for studying learning and memory. More recently, the honey bee has become a valuable model to understand perception and cognition. However, the techniques used to explore psychological phenomena in honey bees have been limited to only a few primary methodologies such as the proboscis extension reflex, sting extension reflex, and free flying target discrimination-tasks. Methods to explore operant conditioning in bees and other invertebrates are not as varied as with vertebrates. This may be due to the availability of a suitable response requirement. In this manuscript we offer a new method to explore operant conditioning in honey bees: the cap pushing response (CPR). We used the CPR to test for difference in learning curves between novel auto-shaping and more traditional explicit-shaping. The CPR protocol requires bees to exhibit a novel behavior by pushing a cap to uncover a food source. Using the CPR protocol we tested the effects of both explicit-shaping and auto-shaping techniques on operant conditioning. The goodness of fit and lack of fit of these data to the Rescorla-Wagner learning-curve model, widely used in classical conditioning studies, was tested. The model fit well to both control and explicit-shaping results, but only for a limited number of trials. Learning ceased rather than continuing to asymptotically approach the physiological most accurate possible. Rate of learning differed between shaped and control bee treatments. Learning rate was about 3 times faster for shaped bees, but for all measures of proficiency control and shaped bees reached the same level. Auto-shaped bees showed one-trial learning rather than the asymptotic approach to a maximal efficiency. However, in terms of return-time, the auto-shaped bees' learning did not carry over to the covered-well test treatments.

Different MK-801 administration schedules induce mild to severe learning impairments in an operant conditioning task: role of buspirone and risperidone in ameliorating these cognitive deficits.

Science.gov (United States)

Rapanelli, Maximiliano; Frick, Luciana Romina; Bernardez-Vidal, Micaela; Zanutto, Bonifacio Silvano

2013-11-15

Blockade of N-methyl-d-aspartate receptor (NMDA) by the noncompetitive NMDA receptor (NMDAR) antagonist MK-801 produces behavioral abnormalities and alterations in prefrontal cortex (PFC) functioning. Due to the critical role of the PFC in operant conditioning task learning, we evaluated the effects of acute, repeated postnatal injections of MK-801 (0.1mg/kg) on learning performance. We injected Long-Evans rats i.p. with MK-801 (0.1mg/kg) using three different administration schedules: injection 40 min before beginning the task (during) (n=12); injection twice daily for six consecutive days prior to beginning the experimental procedures (prior) (n=12); or twice daily subcutaneous injections from postnatal day 7 to 11 (postnatal) (n=12). Next, we orally administered risperidone (serotonin receptor 2A and dopamine receptor 2 antagonist, 1mg/kg) or buspirone (serotonin receptor 1A partial agonist, 10mg/kg) to animals treated with the MK-801 schedule described above. The postnatal and prior administration schedules produced severe learning deficits, whereas injection of MK-801 just before training sessions had only mild effects on acquisition of an operant conditioning. Risperidone was able to reverse the detrimental effect of MK-801 in the animals that were treated with MK-801 during and prior training sessions. In contrast, buspirone was only effective at mitigating the cognitive deficits induced by MK-801 when administered during the training procedures. The data demonstrates that NMDA antagonism disrupts basic mechanisms of learning in a simple PFC-mediated operant conditioning task, and that buspirone and risperidone failed to attenuate the learning deficits when NMDA neurotransmission was blocked in the early stages of the postnatal period. Copyright © 2013 Elsevier B.V. All rights reserved.

A Compact Numerical Implementation for Solving Stokes Equations Using Matrix-vector Operations

KAUST Repository

Zhang, Tao; Salama, Amgad; Sun, Shuyu; Zhong, Hua

2015-01-01

In this work, a numerical scheme is implemented to solve Stokes equations based on cell-centered finite difference over staggered grid. In this scheme, all the difference operations have been vectorized thereby eliminating loops. This is particularly important when using programming languages that require interpretations, e.g., MATLAB and Python. Using this scheme, the execution time becomes significantly smaller compared with non-vectorized operations and also become comparable with those languages that require no repeated interpretations like FORTRAN, C, etc. This technique has also been applied to Navier-Stokes equations under laminar flow conditions.

A Compact Numerical Implementation for Solving Stokes Equations Using Matrix-vector Operations

KAUST Repository

Zhang, Tao

2015-06-01

In this work, a numerical scheme is implemented to solve Stokes equations based on cell-centered finite difference over staggered grid. In this scheme, all the difference operations have been vectorized thereby eliminating loops. This is particularly important when using programming languages that require interpretations, e.g., MATLAB and Python. Using this scheme, the execution time becomes significantly smaller compared with non-vectorized operations and also become comparable with those languages that require no repeated interpretations like FORTRAN, C, etc. This technique has also been applied to Navier-Stokes equations under laminar flow conditions.

Behavioral sensitization after repeated formaldehyde exposure in rats.

Science.gov (United States)

Sorg, B A; Hochstatter, T

1999-01-01

Multiple chemical sensitivity (MCS) is a phenomenon whereby individuals report increased sensitivity to chemicals in the environment, and attribute their sensitivities to prior exposure to the same or often structurally unrelated chemicals. A leading hypothesis suggests that MCS is akin to behavioral sensitization observed in rodents after repeated exposure to drugs of abuse or environmental stressors. Sensitization occurring within limbic circuitry of the central nervous system (CNS) may explain the multisymptom complaints in individuals with MCS. The present studies represent the continuing development of an animal model for MCS, the basis of which is the CNS sensitization hypothesis. Three behaviors were assessed in rats repeatedly exposed to formaldehyde (Form) inhalation. In the first series of experiments, rats were given high-dose Form exposure (11 parts per million [ppm]; 1 h/day x 7 days) or low-dose Form exposure (1 ppm; either 1 h/day x 7 days or 1 h/day x 5 days/week x 4 weeks). Within a few days after discontinuing daily Form, cocaine-induced locomotor activity was elevated after high-dose Form or 20 days of low-dose Form inhalation. Approximately 1 month later, cocaine-induced locomotor activity remained significantly elevated in the 20-day Form-exposed rats. The second experiment assessed whether prior exposure to Form (20 days, as above) would alter the ability to condition to an odor (orange oil) paired with footshock. The results suggested a tendency to increase the conditioned fear response to the odor but not the context of the footshock box, and a decreased tendency to extinguish the conditioned fear response to odor. The third experiment examined whether CNS sensitization to daily cocaine or stress would alter subsequent avoidance responding to odor (Form). Daily cocaine significantly elevated approach responses to Form, while daily stress pretreatment produced a trend in the opposite direction, producing greater avoidance of Form. Preliminary

The incidence of anticipatory nausea and vomiting after repeat cycle chemotherapy: the effect of granisetron.

Science.gov (United States)

Aapro, M. S.; Kirchner, V.; Terrey, J. P.

1994-01-01

Anticipatory nausea and vomiting (ANV) after repeated cycles of cytotoxic chemotherapy is thought to be a conditioned response to a conditioning stimulus. Good control of acute and delayed emesis may result in a lower incidence of ANV. We have analysed data from 574 chemotherapy patients who received granisetron as their antiemetic treatment during repeat cycle chemotherapy. Per treatment cycle, less than 10% of patients displayed symptoms of anticipatory nausea and 2% or less had symptoms of anticipatory vomiting. It is concluded that the use of granisetron as an antiemetic during the acute phase of chemotherapy may result in a lower incidence of ANV in patients undergoing repeat cycle chemotherapy. PMID:8180031

Effects of repeated treatment with MDMA on working memory and behavioural flexibility in mice.

Science.gov (United States)

Viñals, Xavier; Maldonado, Rafael; Robledo, Patricia

2013-03-01

Repeated administration of 3,4-methylenedioxymethamphetamine (MDMA) produces dopaminergic neurotoxicity in mice. However, it is still not clear whether this exposure induces deficits in cognitive processing related to specific subsets of executive functioning. We evaluated the effects of neurotoxic and non-neurotoxic doses of MDMA (0, 3 and 30 mg/kg, twice daily for 4 days) on working memory and attentional set-shifting in mice, and changes in extracellular levels of dopamine (DA) in the striatum. Treatment with MDMA (30 mg/kg) disrupted performance of acquired operant alternation, and this impairment was still apparent 5 days after the last drug administration. Decreased alternation was not related to anhedonia because no differences were observed between groups in the saccharin preference test under similar experimental conditions. Correct responding on delayed alternation was increased 1 day after repeated treatment with MDMA (30 mg/kg), probably because of general behavioural quiescence. Notably, the high dose regimen of MDMA impaired attentional set-shifting related to an increase in total perseveration errors. Finally, basal extracellular levels of DA in the striatum were not modified in mice repeatedly treated with MDMA with respect to controls. However, an acute challenge with MDMA (10 mg/kg) failed to increase DA outflow in mice receiving the highest MDMA dose (30 mg/kg), corroborating a decrease in the functionality of DA transporters. Seven days after this treatment, the effects of MDMA on DA outflow were recovered. These results suggest that repeated neurotoxic doses of MDMA produce lasting impairments in recall of alternation behaviour and reduce cognitive flexibility in mice. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

A Unified Model for Repeating and Non-repeating Fast Radio Bursts

International Nuclear Information System (INIS)

Bagchi, Manjari

2017-01-01

The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

A Unified Model for Repeating and Non-repeating Fast Radio Bursts

Energy Technology Data Exchange (ETDEWEB)

Bagchi, Manjari, E-mail: manjari@imsc.res.in [The Institute of Mathematical Sciences (IMSc-HBNI), 4th Cross Road, CIT Campus, Taramani, Chennai 600113 (India)

2017-04-01

The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

Operational experience at RCD and FCD laboratories during various ventilation conditions

International Nuclear Information System (INIS)

Murali, S.; Ashok Kumar, P.; Thanamani, M.; Rath, D.P.; Sapkal, J.A.; Raman, Anand

2007-01-01

Radiochemistry and Fuel Chemistry wing of Radiological Laboratory facility has various radio-chemical operations on isotopes of plutonium and trans-plutonium elements, carried out under containment and safe operational conditions. The ventilation provided to the facility is a Once - through system. The ventilation system is designed with separate headers for laboratory and glove box exhausts. There is scheduled periodic shut down of ventilation system for maintenance during non-occupancy hours/week ends. The buildup of natural α - emitters activity due to ventilation shut down, observed to be prevailing on stack air sample filter papers after the ventilation startup, is studied. The paper describes the operational experience gained over a period during ventilation shut down and suggests the course of remedial action for reducing the internal exposure due to build up of natural α - emitters and their progenies. (author)

3rd International Conference on Condition Monitoring of Machinery in Non-Stationary Operations

CERN Document Server

Rubini, Riccardo; D'Elia, Gianluca; Cocconcelli, Marco; Chaari, Fakher; Zimroz, Radoslaw; Bartelmus, Walter; Haddar, Mohamed

2014-01-01

This book presents the processings of the third edition of the Condition Monitoring of Machinery in Non-Stationary Operations (CMMNO13) which was held in Ferrara, Italy. This yearly event merges an international community of researchers who met – in 2011 in Wroclaw (Poland) and in 2012 in Hammamet (Tunisia) – to discuss issues of diagnostics of rotating machines operating in complex motion and/or load conditions. The growing interest of the industrial world on the topics covered by the CMMNO13 involves the fields of packaging, automotive, agricultural, mining, processing and wind machines in addition to that of the systems for data acquisition.The participation of speakers and visitors from industry makes the event an opportunity for immediate assessment of the potential applications of advanced methodologies for the signal analysis. Signals acquired from machines often contain contributions from several different components as well as noise. Therefore, the major challenge of condition monitoring is to po...

Repeatability of Cryogenic Multilayer Insulation

Science.gov (United States)

Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

2017-12-01

Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation (MLI) has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five Glenn Research Center (GRC) provided coupons with 25 layers was shown to be +/- 8.4% whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0%. A second group of 10 coupons has been fabricated by Yetispace and tested by Florida State University, the repeatability between coupons has been shown to be +/- 15-25%. Based on detailed statistical analysis, the data has been shown to be statistically significant.

Selection of the optimum condition for electron capture detector operation

International Nuclear Information System (INIS)

Lasa, J.; Korus, A.

1974-01-01

A method of determination of the optimal work conditions for the electron capture detector is presented in the paper. Physical phenomena which occur in the detector, as well as the energetic dependence of the electron attachment process are taken into consideration. The influence of the kind of carrier gas, temperature, and the parameters of the supplied voltage in both direct and pulse methods on average values of electron energy is described. Dependence of the sensitivity of the electron capture detector on the carrier gas and the polarizing voltage is illustrated for the Model DNW-300 electron capture detector produced in Poland. Practical indications for selecting optimal conditions of electron capture detector operation are given at the end of the paper. (author)

Reliability and risk evaluation of a port oil pipeline transportation system in variable operation conditions

Energy Technology Data Exchange (ETDEWEB)

Soszynska, Joanna, E-mail: joannas@am.gdynia.p [Department of Mathematics, Gdynia Maritime University, ul. Morska 83, 81-225 Gdynia (Poland)

2010-02-15

The semi-Markov model of the system operation processes is proposed and its selected characteristics are determined. A system composed on multi-state components is considered and its reliability and risk characteristics are found. Next, the joint model of the system operation process and the system multi-state reliability is applied to the reliability and risk evaluation of the port oil pipeline transportation system. The pipeline system is described and its operation process unknown parameters are identified on the basis of real statistical data. The mean values of the pipeline system operation process unconditional sojourn times in particular operation states are found and applied to determining this process transient probabilities in these states. The piping different reliability structures in various its operation states are fixed and their conditional reliability functions on the basis of data coming from experts are approximately determined. Finally, after applying earlier estimated transient probabilities and system conditional reliability functions in particular operation states the unconditional reliability function, the mean values and standard deviations of the pipeline lifetimes in particular reliability states, risk function and the moment when the risk exceeds a critical value are found.

Reliability and risk evaluation of a port oil pipeline transportation system in variable operation conditions

International Nuclear Information System (INIS)

Soszynska, Joanna

2010-01-01

The semi-Markov model of the system operation processes is proposed and its selected characteristics are determined. A system composed on multi-state components is considered and its reliability and risk characteristics are found. Next, the joint model of the system operation process and the system multi-state reliability is applied to the reliability and risk evaluation of the port oil pipeline transportation system. The pipeline system is described and its operation process unknown parameters are identified on the basis of real statistical data. The mean values of the pipeline system operation process unconditional sojourn times in particular operation states are found and applied to determining this process transient probabilities in these states. The piping different reliability structures in various its operation states are fixed and their conditional reliability functions on the basis of data coming from experts are approximately determined. Finally, after applying earlier estimated transient probabilities and system conditional reliability functions in particular operation states the unconditional reliability function, the mean values and standard deviations of the pipeline lifetimes in particular reliability states, risk function and the moment when the risk exceeds a critical value are found.

Simulation Evaluation of Controller-Managed Spacing Tools under Realistic Operational Conditions

Science.gov (United States)

Callantine, Todd J.; Hunt, Sarah M.; Prevot, Thomas

2014-01-01

Controller-Managed Spacing (CMS) tools have been developed to aid air traffic controllers in managing high volumes of arriving aircraft according to a schedule while enabling them to fly efficient descent profiles. The CMS tools are undergoing refinement in preparation for field demonstration as part of NASA's Air Traffic Management (ATM) Technology Demonstration-1 (ATD-1). System-level ATD-1 simulations have been conducted to quantify expected efficiency and capacity gains under realistic operational conditions. This paper presents simulation results with a focus on CMS-tool human factors. The results suggest experienced controllers new to the tools find them acceptable and can use them effectively in ATD-1 operations.

Computer Simulation of Complex Power System Faults under various Operating Conditions

International Nuclear Information System (INIS)

Khandelwal, Tanuj; Bowman, Mark

2015-01-01

A power system is normally treated as a balanced symmetrical three-phase network. When a fault occurs, the symmetry is normally upset, resulting in unbalanced currents and voltages appearing in the network. For the correct application of protection equipment, it is essential to know the fault current distribution throughout the system and the voltages in different parts of the system due to the fault. There may be situations where protection engineers have to analyze faults that are more complex than simple shunt faults. One type of complex fault is an open phase condition that can result from a fallen conductor or failure of a breaker pole. In the former case, the condition is often accompanied by a fault detectable with normal relaying. In the latter case, the condition may be undetected by standard line relaying. The effect on a generator is dependent on the location of the open phase and the load level. If an open phase occurs between the generator terminals and the high-voltage side of the GSU in the switchyard, and the generator is at full load, damaging negative sequence current can be generated. However, for the same operating condition, an open conductor at the incoming transmission lines located in the switchyard can result in minimal negative sequence current. In 2012, a nuclear power generating station (NPGS) suffered series or open phase fault due to insulator mechanical failure in the 345 kV switchyard. This resulted in both reactor units tripping offline in two separate incidents. Series fault on one of the phases resulted in voltage imbalance that was not detected by the degraded voltage relays. These under-voltage relays did not initiate a start signal to the emergency diesel generators (EDG) because they sensed adequate voltage on the remaining phases exposing a design vulnerability. This paper is intended to help protection engineers calculate complex circuit faults like open phase condition using computer program. The impact of this type of

Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface.

Science.gov (United States)

Sakurai, Yoshio; Song, Kichan; Tachibana, Shota; Takahashi, Susumu

2014-01-01

In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain-machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain-machine interface (BMI). We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them.

Performance evaluation of the DCMD desalination process under bench scale and large scale module operating conditions

KAUST Repository

Francis, Lijo

2014-04-01

The flux performance of different hydrophobic microporous flat sheet commercial membranes made of poly tetrafluoroethylene (PTFE) and poly propylene (PP) was tested for Red Sea water desalination using the direct contact membrane distillation (DCMD) process, under bench scale (high δT) and large scale module (low δT) operating conditions. Membranes were characterized for their surface morphology, water contact angle, thickness, porosity, pore size and pore size distribution. The DCMD process performance was optimized using a locally designed and fabricated module aiming to maximize the flux at different levels of operating parameters, mainly feed water and coolant inlet temperatures at different temperature differences across the membrane (δT). Water vapor flux of 88.8kg/m2h was obtained using a PTFE membrane at high δT (60°C). In addition, the flux performance was compared to the first generation of a new locally synthesized and fabricated membrane made of a different class of polymer under the same conditions. A total salt rejection of 99.99% and boron rejection of 99.41% were achieved under extreme operating conditions. On the other hand, a detailed water characterization revealed that low molecular weight non-ionic molecules (ppb level) were transported with the water vapor molecules through the membrane structure. The membrane which provided the highest flux was then tested under large scale module operating conditions. The average flux of the latter study (low δT) was found to be eight times lower than that of the bench scale (high δT) operating conditions.

Numerical simulation of hydrodynamics in a pump-turbine at off-design operating conditions in turbine mode

International Nuclear Information System (INIS)

Yan, J P; Seidel, U; Koutnik, J

2012-01-01

The hydrodynamics of a reduced-scaled model of a radial pump-turbine is investigated under off-design operating conditions, involving runaway and 'S-shape' turbine brake curve at low positive discharge. It is a low specific speed pump-turbine machine of Francis type with 9 impeller blades and 20 stay vanes as well as 20 guide vanes. The computational domain includes the entire water passage from the spiral casing inlet to the draft tube outlet. Completely structured hexahedral meshes generated by the commercial software ANSYS-ICEM are employed. The unsteady incompressible simulations are performed using the commercial code ANSYS-CFX13. For turbulence modeling the standard k-ε model is applied. The numerical results at different operating points are compared to the experimental results. The predicted pressure amplitude is in good agreement with the experimental data and the amplitude of normal force on impeller is in reasonable range. The detailed analysis reveals the onset of the flow instabilities when the machine is brought from a regular operating condition to runaway and turbine break mode. Furthermore, the rotating stall phenomena are well captured at runaway condition as well as low discharge operating condition with one stall cell rotating inside and around the impeller with about 70% of its frequency. Moreover, the rotating stall is found to be the effect of rotating flow separations developed in several consecutive impeller channels which lead to their blockage. The reliable simulation of S-curve characteristics in pump-turbines is a basic requirement for design and optimization at off-design operating conditions.

Performance evaluation of the DCMD desalination process under bench scale and large scale module operating conditions

KAUST Repository

Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Nunes, Suzana Pereira; Amy, Gary L.

2014-01-01

The flux performance of different hydrophobic microporous flat sheet commercial membranes made of poly tetrafluoroethylene (PTFE) and poly propylene (PP) was tested for Red Sea water desalination using the direct contact membrane distillation (DCMD) process, under bench scale (high δT) and large scale module (low δT) operating conditions. Membranes were characterized for their surface morphology, water contact angle, thickness, porosity, pore size and pore size distribution. The DCMD process performance was optimized using a locally designed and fabricated module aiming to maximize the flux at different levels of operating parameters, mainly feed water and coolant inlet temperatures at different temperature differences across the membrane (δT). Water vapor flux of 88.8kg/m2h was obtained using a PTFE membrane at high δT (60°C). In addition, the flux performance was compared to the first generation of a new locally synthesized and fabricated membrane made of a different class of polymer under the same conditions. A total salt rejection of 99.99% and boron rejection of 99.41% were achieved under extreme operating conditions. On the other hand, a detailed water characterization revealed that low molecular weight non-ionic molecules (ppb level) were transported with the water vapor molecules through the membrane structure. The membrane which provided the highest flux was then tested under large scale module operating conditions. The average flux of the latter study (low δT) was found to be eight times lower than that of the bench scale (high δT) operating conditions.

Operating wind turbines in strong wind conditions by using feedforward-feedback control

International Nuclear Information System (INIS)

Feng, Ju; Sheng, Wen Zhong

2014-01-01

Due to the increasing penetration of wind energy into power systems, it becomes critical to reduce the impact of wind energy on the stability and reliability of the overall power system. In precedent works, Shen and his co-workers developed a re-designed operation schema to run wind turbines in strong wind conditions based on optimization method and standard PI feedback control, which can prevent the typical shutdowns of wind turbines when reaching the cut-out wind speed. In this paper, a new control strategy combing the standard PI feedback control with feedforward controls using the optimization results is investigated for the operation of variable-speed pitch-regulated wind turbines in strong wind conditions. It is shown that the developed control strategy is capable of smoothening the power output of wind turbine and avoiding its sudden showdown at high wind speeds without worsening the loads on rotor and blades

PATs Operating in Water Networks under Unsteady Flow Conditions: Control Valve Manoeuvre and Overspeed Effect

Directory of Open Access Journals (Sweden)

Modesto Pérez-Sánchez

2018-04-01

Full Text Available The knowledge of transient conditions in water pressurized networks equipped with pump as turbines (PATs is of the utmost importance and necessary for the design and correct implementation of these new renewable solutions. This research characterizes the water hammer phenomenon in the design of PAT systems, emphasizing the transient events that can occur during a normal operation. This is based on project concerns towards a stable and efficient operation associated with the normal dynamic behaviour of flow control valve closure or by the induced overspeed effect. Basic concepts of mathematical modelling, characterization of control valve behaviour, damping effects in the wave propagation and runaway conditions of PATs are currently related to an inadequate design. The precise evaluation of basic operating rules depends upon the system and component type, as well as the required safety level during each operation.

Deployment Repeatability

Science.gov (United States)

2016-04-01

evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

Travel report on a preparatory mission to the Agencija RAO, Ljubljana for a radium conditioning operation

International Nuclear Information System (INIS)

Neubauer, J.

2001-07-01

The purpose of the trip was to establish the current status of radioactive waste management in Slovenia, to discuss their plans for the future management of their radioactive wastes and to prepare for a radium source conditioning operation to make safe and secure their known inventory of radium withdrawn from service. The IAEA are considering placing a contract on the Oesterreichisches Forschungszentrum Seibersdorf (OeFZS) to carry out the radium conditioning operation on the agency's behalf in a manner used successfully on a number of previous occasions. In Slovenia responsibility for the management of radioactive wastes arising from nuclear applications in medicine research and industry is delegated to 'Agencija Rao'. First a visit was made to the storage building in which such wastes are stored, the building being within the grounds of the Josef Stefan Institute in Ljubljana. The possibility of carrying out the radium conditioning operation in the building and the improvements and modifications necessary was discussed. The inventory of stored waste was reviewed, the packages containing radium were identified and located in the store. Some of these contained radium-beryllium sources. It was agreed that such sources would not be conditioned during the forthcoming operation. Next a visit was made to the chemistry laboratories of the Josef Stefan Institute, these being a possible alternative location for the operation. On returning to the 'Agencija Rao' office in Ljubljana detail discussion of the merits of the alternative locations were discussed. It was realized that the operation could proceed quicker and at less cost if the existing laboratory was chosen, the unknown factor is the time taken to obtain regulatory approval. Next detailed discussion took place of the availability of necessary equipment and consumable items and agreement reached on what should be supplied locally and what should be brought to Slovenia, by the conditioning team. Plans were made to

Introducing you to satellite operated data collection platforms (DCP).

CSIR Research Space (South Africa)

Stavropoulos, CC

1977-09-01

Full Text Available and operate in the VHF, UHF or microwave bands. By using a satellite as a repeater, large distances over land and sea can be covered with a single repeater in the sky. Trans-continental links for communication purposes have been operational for many years...

Reconfigurable multiport EPON repeater

Science.gov (United States)

Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

2009-11-01

An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

Repeated nicotine exposure enhances reward-related learning in the rat.

Science.gov (United States)

Olausson, Peter; Jentsch, J David; Taylor, Jane R

2003-07-01

Repeated exposure to addictive drugs causes neuroadaptive changes in cortico-limbic-striatal circuits that may underlie alterations in incentive-motivational processes and reward-related learning. Such drug-induced alterations may be relevant to drug addiction because enhanced incentive motivation and increased control over behavior by drug-associated stimuli may contribute to aspects of compulsive drug-seeking and drug-taking behaviors. This study investigated the consequences of repeated nicotine treatment on the acquisition and performance of Pavlovian discriminative approach behavior, a measure of reward-related learning, in male rats. Water-restricted rats were trained to associate a compound conditioned stimulus (tone+light) with the availability of water (the unconditioned stimulus) in 15 consecutive daily sessions. In separate experiments, rats were repeatedly treated with nicotine (0.35 mg/kg, s.c.) either (1) prior to the onset of training, (2) after each daily training session was completed (ie postsession injections), or (3) received nicotine both before the onset of training as well as after each daily training session. In this study, all nicotine treatment schedules increased Pavlovian discriminative approach behavior and, thus, prior repeated exposure to nicotine, repeated postsession nicotine injections, or both, facilitated reward-related learning.

A Paradigm for Operant Conditioning in Blow Flies ("Phormia Terrae Novae" Robineau-Desvoidy, 1830)

Science.gov (United States)

Sokolowski, Michel B. C.; Disma, Gerald; Abramson, Charles I.

2010-01-01

An operant conditioning situation for the blow fly ("Protophormia terrae novae") is described. Individual flies are trained to enter and reenter a hole as the operant response. Only a few sessions of contingent reinforcement are required to increase response rates. When the response is no longer followed by food, the rate of entering the hole…

The Other Shoe: An Early Operant Conditioning Chamber for Pigeons

OpenAIRE

Sakagami, Takayuki; Lattal, Kennon A.

2016-01-01

We describe an early operant conditioning chamber fabricated by Harvard University instrument maker Ralph Gerbrands and shipped to Japan in 1952 in response to a request of Professor B. F. Skinner by Japanese psychologists. It is a rare example, perhaps the earliest still physically existing, of such a chamber for use with pigeons. Although the overall structure and many of the components are similar to contemporary pigeon chambers, several differences are noted and contrasted to evolutionary...

Evaluation of the nervous-psychic working ability of the operators of the Kozloduj NPP concerning their health conditions

International Nuclear Information System (INIS)

Jonkova, A.

1988-01-01

By means of psychological methods the neuroticism and work tiredness in 170 operators from the Kozloduj NPP have been investigated. The distribution of the individuals with work overtiredness according to health conditions and the operative service duration was considered. In 73 operators, who had sufficiently informative complaints of overtiredness, a high incidence of cardiocascular and gastrointestinal diseases, of neuroses and increased neuroticism was established. The relative part of the individuals with overtiredness augmented substantially after 5-year duration service. Since overtiredness is an inadmissible functional condition for operators, its observation in 42,9% of the examined contingent is estimated as a real danger for decrease of the reliability and for worsening of the health conditions

Towards artificial intelligence based diesel engine performance control under varying operating conditions using support vector regression

Directory of Open Access Journals (Sweden)

Naradasu Kumar Ravi

2013-01-01

Full Text Available Diesel engine designers are constantly on the look-out for performance enhancement through efficient control of operating parameters. In this paper, the concept of an intelligent engine control system is proposed that seeks to ensure optimized performance under varying operating conditions. The concept is based on arriving at the optimum engine operating parameters to ensure the desired output in terms of efficiency. In addition, a Support Vector Machines based prediction model has been developed to predict the engine performance under varying operating conditions. Experiments were carried out at varying loads, compression ratios and amounts of exhaust gas recirculation using a variable compression ratio diesel engine for data acquisition. It was observed that the SVM model was able to predict the engine performance accurately.

42 CFR 433.130 - Waiver of conditions of initial operation and approval.

Science.gov (United States)

2010-10-01

... Claims Processing and Information Retrieval Systems § 433.130 Waiver of conditions of initial operation... system will not significantly improve the efficiency of the administration of the State plan. (c) If CMS... waiver, that a system would significantly improve the administration of the State Medicaid program, CMS...

Availability analysis of a turbocharged diesel engine operating under transient load conditions

International Nuclear Information System (INIS)

Rakopoulos, C.D.; Giakoumis, E.G.

2004-01-01

A computer analysis is developed for studying the energy and availability performance of a turbocharged diesel engine, operating under transient load conditions. The model incorporates many novel features for the simulation of transient operation, such as detailed analysis of mechanical friction, separate consideration for the processes of each cylinder during a cycle ('multi-cylinder' model) and mathematical modeling of the fuel pump. This model has been validated against experimental data taken from a turbocharged diesel engine, located at the authors' laboratory and operated under transient conditions. The availability terms for the diesel engine and its subsystems are analyzed, i.e. cylinder for both the open and closed parts of the cycle, inlet and exhaust manifolds, turbocharger and aftercooler. The present analysis reveals, via multiple diagrams, how the availability properties of the diesel engine and its subsystems develop during the evolution of the engine cycles, assessing the importance of each property. In particular the irreversibilities term, which is absent from any analysis based solely on the first-law of thermodynamics, is given in detail as regards transient response as well as the rate and cumulative terms during a cycle, revealing the magnitude of contribution of all the subsystems to the total availability destruction

A Flexible 5G Wide Area Solution for TDD with Asymmetric Link Operation

DEFF Research Database (Denmark)

Pedersen, Klaus I.; Berardinelli, Gilberto; Frederiksen, Frank

2017-01-01

optimization on a per-link basis is proposed. The solution encompasses the possibility to schedule users with different transmission time intervals to best match their service equirements and radio conditions. Due to the large downlink/uplink transmission power imbalance for each link, asymmetric link...... operation is proposed, where users operate with different minimum transmission times for the two link directions. This is achieved by using a highly flexible asynchronous hybrid Automatic repeat request (HARQ) scheme, as well as a novel solution with in-resource control channel signaling for the scheduling...

Teaching giant african pouched rats to find landmines: operant conditioning with real consequences.

Science.gov (United States)

Poling, Alan; Weetjens, Bart J; Cox, Christophe; Beyene, Negussie; Bach, Håvard; Sully, Andrew

2010-01-01

Giant African pouched rats recently have been used as mine-detection animals in Mozambique. To provide an example of the wide range of problems to which operant conditioning procedures can be applied and to illustrate the common challenges often faced in applying those procedures, this manuscript briefly describes how the rats are trained and used operationally. To date, the rats have performed well and it appears they can play a valuable role in humanitarian demining.

Repeatability and Reproducibility of Fibre-Based Nanogenerator Synthesized by Electrospinning Machine

International Nuclear Information System (INIS)

Suyitno; Huda, Sholiehul; Arifin, Zainal; Hadi, Syamsul; Lambang, Raymundus Lullus

2014-01-01

Zinc oxide fibres-based nanogenerators synthesized easily by electrospinning machine are promising to harvest electricity from mechanical energy. However, the repeatability and reproducibility were two major factors needed to be investigated to minimize product failure and to determine the feasibility of mass production of nanogenerators. The green fibres of zinc oxide were produced by electrospinning machine of zinc acetate and polyvinyl alcohol solution at a flow rate of 4 μL/min followed by sintering at temperature 550°C with heating rate 240°C/h. Each 10 nanogenerators was tested by three trained operators with three times of repetition at compressive load 0.5 kg. The nanogenerators revealed the maximum output voltage ranging from 203 to 217 mV. The value of repeatability and reproducibility of nanogenerators was approximately 24.29% showing that nanogenerators were still acceptable to be mass-produced. The relatively low reproducibility was mainly due to the operators, so that the checklist needed to be made easier and simpler for all the variables affecting to the quality of the fibres. Reducing the value of the repeatability and reproducibility is interesting to study further by creating a rotating collector so that the thickness and orientation of fibres can be arranged better

Analysis of WWER-440 fuel performance under normal operating conditions

Energy Technology Data Exchange (ETDEWEB)

Gunduz, Oe; Koese, S; Akbas, T [Atomenerjisi Komisyonu, Ankara (Turkey); Colak, Ue [Ankara Nuclear Research and Training Center (Turkey)

1994-12-31

FRAPCON-2 code originally developed for LWR fuel behaviour simulation is used to analyse the WWER-440 fuel rod behaviour at normal operational conditions. The code is capable of utilizing different models for mechanical analysis and gas release calculations. Heat transfer calculations are accomplished through a collocation technique by the method of weighted residuals. Temperature and burnup element properties are evaluated using MATPRO package. As the material properties of Zr-1%Nb used as cladding in WWER-440s are not provided in the code, Zircaloy-4 is used as a substitute for Zr-1%Nb. Mac-Donald-Weisman model is used for gas release calculation. FRACAS-1 and FRACAS-2 models are used in the mechanical calculations. It is assumed that the reactor was operated for 920 days (three consecutive cycles), the burnup being 42000 Mwd/t U. Results of the fuel rod behaviour analysis are given for three axial nodes: bottom node, central node and top node. The variations of the following characteristic fuel rod parameters are studied through the prescribed power history: unmoved gap thickness, gap heat transfer coefficient, fuel axial elongation, cladding axial elongation, fuel centerline temperature and ZrO-thickness at cladding surface. The value of each parameter is calculated as a function of the effective power days for the three nodes by using FRACAS-1 and FRACAS-2 codes for comparison.The results show that calculations with deformable pellet approximation with FRACAS-II model could provide better information for the behaviour of a typical fuel rod. Calculations indicate that fuel rod failure is not observed during the operation. All fuel rod parameters investigated are found to be within the safety limits. It is concluded, however, that for better assessment of reactor safety these calculations should be extended for transient conditions such as LOCA. 1 tab., 10 figs., 4 refs.

Operating experience with a high capacity helium pump under supercritical conditions

International Nuclear Information System (INIS)

Lehmann, W.; Minges, J.

1984-01-01

This chapter discusses the development and testing of a high-capacity piston pump to provide forced cooling for large superconducting magnets. The pump is a three cylinder, vertically arranged single-acting piston pump equipped with a frequency controlled three-phase geared motor operating at room temperature. The pump is capable of delivering up to 150 g/s at a maximum speed of 310 rpm and under the inlet conditions of 4 bar/4.5 K. No decline was noticed in delivery head and efficiencies during more than 560 hours of operation. It is concluded that the pump satisfies all requirements for circulating large mass flows across great pressure differences as needed (e.g. in fusion magnet design)

Implementation of high fidelity models for the conditions of operation in stop in PWR simulators

International Nuclear Information System (INIS)

Gonzalez Sevillano, I.; Jimenez Bogarin, R.; Ortega Pascual, F.

2014-01-01

The operation in stop cold conditions and in particular the States of operation with reduced inventory, the call of half loop or half nozzle, is becoming increasingly more important. These States of operation are characterized by having the coolant level approximately on the generatrix of the branches, so that any deviation in the level or malfunction of the system for the disposal of waste heat could lead to compromising situations. The importance of this type of situation is reflected in the APS in other modes (APSOM), which show that the risk in these conditions may be comparable to the power. Hence the importance that the simulator training programmes include scenarios that cover these States of operation. The article describes on the one hand, the difficulties encountered in the simulation of situations characterized by low pressure and presence of Non-Condensable and, on the other hand, its implementation, not only in the field of training of plant personnel, but also in the field of review/validation of operating procedures. (Author)

Aerodynamic performance of a vibrating piezoelectric fan under varied operational conditions

International Nuclear Information System (INIS)

Stafford, J; Jeffers, N

2014-01-01

This paper experimentally examines the bulk aerodynamic performance of a vibrating fan operating in the first mode of vibration. The influence of operating condition on the local velocity field has also been investigated to understand the flow distribution at the exit region and determine the stalling condition for vibrating fans. Fan motion has been generated and controlled using a piezoelectric ceramic attached to a stainless steel cantilever. The frequency and amplitude at resonance were 109.4 Hz and 12.5 mm, respectively. A test facility has been developed to measure the pressure-flow characteristics of the vibrating fan and simultaneously conduct local velocity field measurements using particle image velocimetry. The results demonstrate the impact of system characteristics on the local velocity field. High momentum regions generated due to the oscillating motion exist with a component direction that is tangent to the blade at maximum displacement. These high velocity zones are significantly affected by increasing impedance while flow reversal is a dominant feature at maximum pressure rise. The findings outlined provide useful information for design of thermal management solutions that may incorporate this air cooling approach.

Evaluation of LWR fuel rod behavior under operational transient conditions

International Nuclear Information System (INIS)

Nakamura, M.; Hiramoto, K.; Maru, A.

1984-01-01

To evaluate the effects of fission gas flow and diffusion in the fuel-cladding gap on fuel rod thermal and mechanical behaviors in light water reactor (LWR) fuel rods under operational transient conditions, computer sub-programs which can calculate the gas flow and diffusion have been developed and integrated into the LWR fuel rod performance code BEAF. This integrated code also calculates transient temperature distribution in the fuel-pellet and cladding. The integrated code was applied to an analysis of Inter Ramp Project data, which showed that by taking into account the gas flow and diffusion effects, the calculated cladding damage indices predicted for the failed rods in the ramp test were consistent with iodine-SCC (Stress Corrosion Cracking) failure conditions which were obtained from out-of-reactor pressurized tube experiments with irradiated Zircaloy claddings. This consistency was not seen if the gas flow and diffusion effects were neglected. Evaluation were also made for the BWR 8x8 RJ fuel rod temperatures under power ramp conditions. (orig.)

New oil condition monitoring system, Wearsens® enables continuous, online detection of critical operating conditions and wear damage

Directory of Open Access Journals (Sweden)

Manfred Mauntz

2015-12-01

Full Text Available A new oil sensor system is presented for the continuous, online measurement of the wear in turbines, industrial gears, generators, hydraulic systems and transformers. Detection of change is much earlier than existing technologies such as particle counting, vibration measurement or recording temperature. Thus targeted, corrective procedures and/or maintenance can be carried out before actual damage occurs. Efficient machine utilization, accurately timed preventive maintenance, increased service life and a reduction of downtime can all be achieved. The presented sensor system effectively controls the proper operation conditions of bearings and cogwheels in gears. The online diagnostics system measures components of the specific complex impedance of oils. For instance, metal abrasion due to wear debris, broken oil molecules, forming acids or oil soaps, result in an increase of the electrical conductivity, which directly correlates with the degree of contamination of the oil. For additivated lubricants, the stage of degradation of the additives can also be derived from changes in the dielectric constant. The determination of impurities or reduction in the quality of the oil and the quasi continuous evaluation of wear and chemical aging follow the holistic approach of a real-time monitoring of an alteration in the condition of the oil-machine system. Once the oil condition monitoring sensors are installed on the wind turbine, industrial gearbox and test stands, the measuring data can be displayed and evaluated elsewhere. The signals are transmitted to a web-based condition monitoring system via LAN, WLAN or serial interfaces of the sensor unit. Monitoring of the damage mechanisms during proper operation below the tolerance limits of the components enables specific preventive maintenance independent of rigid inspection intervals.

Effect of heavy back squats on repeated sprint performance in trained men.

Science.gov (United States)

Duncan, M J; Thurgood, G; Oxford, S W

2014-04-01

This study examined the impact of post activation potentiation on repeated sprint performance in trained Rugby Union players. Ten, male, professional Rugby Union players (mean age=25.2±5.02 years) performed 7, 30-meter sprints, separated by 25 seconds, 4 minutes following back squats (90% 1 repetition maximum) or a control condition performed in a counterbalanced order. Significant condition X sprint interactions for 10-meter (P=0.02) and 30-meter (P=0.05) indicated that times were significantly faster in the PAP condition for sprints 5, 6 and 7 across both distances. Fatigue rate was also significantly lower in the PAP condition for 10-meter (P=0.023) and 30-meter (P=0.006) sprint running speed. This study evidences that a heavy resistance exercise stimulus administered four minutes prior to repeated sprints can offset the decline in sprint performance seen during subsequent maximal sprinting over 10 and 30-meters in Rugby Union players.

A SVDD and K-Means Based Early Warning Method for Dual-Rotor Equipment under Time-Varying Operating Conditions

Directory of Open Access Journals (Sweden)

Zhinong Jiang

2018-01-01

Full Text Available Under frequently time-varying operating conditions, equipment with dual rotors like gas turbines is influenced by two rotors with different rotating speeds. Alarm methods of fixed threshold are unable to consider the influences of time-varying operating conditions. Hence, those methods are not suitable for monitoring dual-rotor equipment. An early warning method for dual-rotor equipment under time-varying operating conditions is proposed in this paper. The influences of time-varying rotating speeds of dual rotors on alarm thresholds have been considered. Firstly, the operating conditions are divided into several limited intervals according to rotating speeds of dual rotors. Secondly, the train data within each interval is processed by SVDD and the allowable ranges (i.e., the alarm threshold of the vibration are determined. The alarm threshold of each interval of operating conditions is obtained. The alarm threshold can be expressed as a sphere, whose controlling parameters are the coordinate of the center and the radius. Then, the cluster center of the test data, whose alarm state is to be judged, can be extracted through K-means. Finally, the alarm state can be obtained by comparing the cluster center with the corresponding sphere. Experiments are conducted to validate the proposed method.

Restoring walking after spinal cord injury: operant conditioning of spinal reflexes can help.

Science.gov (United States)

Thompson, Aiko K; Wolpaw, Jonathan R

2015-04-01

People with incomplete spinal cord injury (SCI) frequently suffer motor disabilities due to spasticity and poor muscle control, even after conventional therapy. Abnormal spinal reflex activity often contributes to these problems. Operant conditioning of spinal reflexes, which can target plasticity to specific reflex pathways, can enhance recovery. In rats in which a right lateral column lesion had weakened right stance and produced an asymmetrical gait, up-conditioning of the right soleus H-reflex, which increased muscle spindle afferent excitation of soleus, strengthened right stance and eliminated the asymmetry. In people with hyperreflexia due to incomplete SCI, down-conditioning of the soleus H-reflex improved walking speed and symmetry. Furthermore, modulation of electromyographic activity during walking improved bilaterally, indicating that a protocol that targets plasticity to a specific pathway can trigger widespread plasticity that improves recovery far beyond that attributable to the change in the targeted pathway. These improvements were apparent to people in their daily lives. They reported walking faster and farther, and noted less spasticity and better balance. Operant conditioning protocols could be developed to modify other spinal reflexes or corticospinal connections; and could be combined with other therapies to enhance recovery in people with SCI or other neuromuscular disorders. © The Author(s) 2014.

Expansion of protein domain repeats.

Directory of Open Access Journals (Sweden)

Asa K Björklund

2006-08-01

Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

Experimental determination of drift and PM10 cooling tower emissions: Influence of components and operating conditions.

Science.gov (United States)

Ruiz, J; Kaiser, A S; Lucas, M

2017-11-01

Cooling tower emissions have become an increasingly common hazard to the environment (air polluting, ice formation and salts deposition) and to the health (Legionella disease) in the last decades. Several environmental policies have emerged in recent years limiting cooling tower emissions but they have not prevented an increasing intensity of outbreaks. Since the level of emissions depends mainly on cooling tower component design and the operating conditions, this paper deals with an experimental investigation of the amount of emissions, drift and PM 10 , emitted by a cooling tower with different configurations (drift eliminators and distribution systems) and working under several operating conditions. This objective is met by the measurement of cooling tower source emission parameters by means of the sensitive paper technique. Secondary objectives were to contextualize the observed emission rates according to international regulations. Our measurements showed that the drift rates included in the relevant international standards are significantly higher than the obtained results (an average of 100 times higher) and hence, the environmental problems may occur. Therefore, a revision of the standards is recommended with the aim of reducing the environmental and human health impact. By changing the operating conditions and the distribution system, emissions can be reduced by 52.03% and 82% on average. In the case of drift eliminators, the difference ranges from 18.18% to 98.43% on average. As the emissions level is clearly influenced by operating conditions and components, regulation tests should be referred to default conditions. Finally, guidelines to perform emission tests and a selection criterion of components and conditions for the tested cooling tower are proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel attention training paradigm based on operant conditioning of eye gaze: Preliminary findings.

Science.gov (United States)

Price, Rebecca B; Greven, Inez M; Siegle, Greg J; Koster, Ernst H W; De Raedt, Rudi

2016-02-01

Inability to engage with positive stimuli is a widespread problem associated with negative mood states across many conditions, from low self-esteem to anhedonic depression. Though attention retraining procedures have shown promise as interventions in some clinical populations, novel procedures may be necessary to reliably attenuate chronic negative mood in refractory clinical populations (e.g., clinical depression) through, for example, more active, adaptive learning processes. In addition, a focus on individual difference variables predicting intervention outcome may improve the ability to provide such targeted interventions efficiently. To provide preliminary proof-of-principle, we tested a novel paradigm using operant conditioning to train eye gaze patterns toward happy faces. Thirty-two healthy undergraduates were randomized to receive operant conditioning of eye gaze toward happy faces (train-happy) or neutral faces (train-neutral). At the group level, the train-happy condition attenuated sad mood increases following a stressful task, in comparison to train-neutral. In individual differences analysis, greater physiological reactivity (pupil dilation) in response to happy faces (during an emotional face-search task at baseline) predicted decreased mood reactivity after stress. These Preliminary results suggest that operant conditioning of eye gaze toward happy faces buffers against stress-induced effects on mood, particularly in individuals who show sufficient baseline neural engagement with happy faces. Eye gaze patterns to emotional face arrays may have a causal relationship with mood reactivity. Personalized medicine research in depression may benefit from novel cognitive training paradigms that shape eye gaze patterns through feedback. Baseline neural function (pupil dilation) may be a key mechanism, aiding in iterative refinement of this approach. (c) 2016 APA, all rights reserved).

Early detection of power system disturbances as a condition for safe operation of the Dukovany NPP in the 'Island operation mode'

International Nuclear Information System (INIS)

Petruzela, I.

1997-01-01

The ''Frequency Plan'' worked out for the Czech Power System specifies a set of preventive measures along with the set of the frequency ranges. This problem was solved in details for the Dukovany nuclear power plant. The design changes under preparation support a reliable as well as safe operation in the island-operation mode until a full restoration of the whole power system. The design modifications are based on the following three main innovations: An incorporation of the FREA 16 frequency relay into the protection circuits; large modifications in turbine control loops; installation of software routine for the operator to support the island operation mode. The capability of the island operation has been demanded by relevant regulations both for the operating units and for that under construction. The capability can be tested under the transition to houseloads, as well as through the direct simulation of abnormal grid conditions. 1 fig

Two-dimensional quantum repeaters

Science.gov (United States)

Wallnöfer, J.; Zwerger, M.; Muschik, C.; Sangouard, N.; Dür, W.

2016-11-01

The endeavor to develop quantum networks gave rise to a rapidly developing field with far-reaching applications such as secure communication and the realization of distributed computing tasks. This ultimately calls for the creation of flexible multiuser structures that allow for quantum communication between arbitrary pairs of parties in the network and facilitate also multiuser applications. To address this challenge, we propose a two-dimensional quantum repeater architecture to establish long-distance entanglement shared between multiple communication partners in the presence of channel noise and imperfect local control operations. The scheme is based on the creation of self-similar multiqubit entanglement structures at growing scale, where variants of entanglement swapping and multiparty entanglement purification are combined to create high-fidelity entangled states. We show how such networks can be implemented using trapped ions in cavities.

Predators in training: operant conditioning of novel behavior in wild Burmese pythons (Python molurus bivitattus).

Science.gov (United States)

Emer, Sherri A; Mora, Cordula V; Harvey, Mark T; Grace, Michael S

2015-01-01

Large pythons and boas comprise a group of animals whose anatomy and physiology are very different from traditional mammalian, avian and other reptilian models typically used in operant conditioning. In the current study, investigators used a modified shaping procedure involving successive approximations to train wild Burmese pythons (Python molurus bivitattus) to approach and depress an illuminated push button in order to gain access to a food reward. Results show that these large, wild snakes can be trained to accept extremely small food items, associate a stimulus with such rewards via operant conditioning and perform a contingent operant response to gain access to a food reward. The shaping procedure produced robust responses and provides a mechanism for investigating complex behavioral phenomena in massive snakes that are rarely studied in learning research.

Control-limit preventive maintenance policies for components subject to imperfect preventive maintenance and variable operational conditions

International Nuclear Information System (INIS)

You Mingyi; Li Hongguang; Meng Guang

2011-01-01

This paper develops two component-level control-limit preventive maintenance (PM) policies for systems subject to the joint effect of partial recovery PM acts (imperfect PM acts) and variable operational conditions, and investigates the properties of the proposed policies. The extended proportional hazards model (EPHM) is used to model the system failure likelihood influenced by both factors. Several numerical experiments are conducted for policy property analysis, using real lifetime and operational condition data and typical characterization of imperfect PM acts and maintenance durations. The experimental results demonstrate the necessity of considering both factors when they do exist, characterize the joint effect of the two factors on the performance of an optimized PM policy, and explore the influence of the loading sequence of time-varying operational conditions on the performance of an optimized PM policy. The proposed policies extend the applicability of PM optimization techniques.

Parallel Multi-cycle LES of an Optical Pent-roof DISI Engine Under Motored Operating Conditions

Energy Technology Data Exchange (ETDEWEB)

Van Dam, Noah; Sjöberg, Magnus; Zeng, Wei; Som, Sibendu

2017-10-15

The use of Large-eddy Simulations (LES) has increased due to their ability to resolve the turbulent fluctuations of engine flows and capture the resulting cycle-to-cycle variability. One drawback of LES, however, is the requirement to run multiple engine cycles to obtain the necessary cycle statistics for full validation. The standard method to obtain the cycles by running a single simulation through many engine cycles sequentially can take a long time to complete. Recently, a new strategy has been proposed by our research group to reduce the amount of time necessary to simulate the many engine cycles by running individual engine cycle simulations in parallel. With modern large computing systems this has the potential to reduce the amount of time necessary for a full set of simulated engine cycles to finish by up to an order of magnitude. In this paper, the Parallel Perturbation Methodology (PPM) is used to simulate up to 35 engine cycles of an optically accessible, pent-roof Directinjection Spark-ignition (DISI) engine at two different motored engine operating conditions, one throttled and one un-throttled. Comparisons are made against corresponding sequential-cycle simulations to verify the similarity of results using either methodology. Mean results from the PPM approach are very similar to sequential-cycle results with less than 0.5% difference in pressure and a magnitude structure index (MSI) of 0.95. Differences in cycle-to-cycle variability (CCV) predictions are larger, but close to the statistical uncertainty in the measurement for the number of cycles simulated. PPM LES results were also compared against experimental data. Mean quantities such as pressure or mean velocities were typically matched to within 5- 10%. Pressure CCVs were under-predicted, mostly due to the lack of any perturbations in the pressure boundary conditions between cycles. Velocity CCVs for the simulations had the same average magnitude as experiments, but the experimental data showed

Coordinated hybrid automatic repeat request

KAUST Repository

Makki, Behrooz

2014-11-01

We develop a coordinated hybrid automatic repeat request (HARQ) approach. With the proposed scheme, if a user message is correctly decoded in the first HARQ rounds, its spectrum is allocated to other users, to improve the network outage probability and the users\\' fairness. The results, which are obtained for single- and multiple-antenna setups, demonstrate the efficiency of the proposed approach in different conditions. For instance, with a maximum of M retransmissions and single transmit/receive antennas, the diversity gain of a user increases from M to (J+1)(M-1)+1 where J is the number of users helping that user.

OPTIMIZATION OF SESAME SEEDS OIL EXTRACTION OPERATING CONDITIONS USING THE RESPONSE SURFACE DESIGN METHODOLOGY

Directory of Open Access Journals (Sweden)

HAITHAM OSMAN

2016-12-01

Full Text Available This paper applies Response Surface Design (RSD to model the experimental data obtained from the extraction of sesame seeds oil using n-hexane, chloroform and acetone as solvents under different operating conditions. The results obtained revealed that n-hexane outperformed the extraction obtained using chloroform and acetone. The developed model predicted that n-hexane with a rotational speed of 547 rpm and a contact time between the solvent and seeds of 19.46 hours with solvent: seeds ratio of 4.93, yields the optimum oil extracted of 37.03 %, outperforming chloroform and acetone models that gave prediction for 4.75 and 4.21 respectively. While the maximum predictions yield for chloroform is 6.73 %, under the operating conditions of 602 rpm, and 24 hours contact time, with a ratio of solvent: seeds of 1.74. On the other hand the acetone maximum prediction is only 4.37 %, with operational conditions of 467 rpm, and 6.00 hours contact time, with a ratio of solvent: seeds of 1. It is has been found that the maximum oil extraction yield obtained from the chloroform (6.73 % and Acetone (4.37 % is much lower than that predicted by n-hexane 37.03 %.

The leucine-rich repeat structure.

Science.gov (United States)

Bella, J; Hindle, K L; McEwan, P A; Lovell, S C

2008-08-01

The leucine-rich repeat is a widespread structural motif of 20-30 amino acids with a characteristic repetitive sequence pattern rich in leucines. Leucine-rich repeat domains are built from tandems of two or more repeats and form curved solenoid structures that are particularly suitable for protein-protein interactions. Thousands of protein sequences containing leucine-rich repeats have been identified by automatic annotation methods. Three-dimensional structures of leucine-rich repeat domains determined to date reveal a degree of structural variability that translates into the considerable functional versatility of this protein superfamily. As the essential structural principles become well established, the leucine-rich repeat architecture is emerging as an attractive framework for structural prediction and protein engineering. This review presents an update of the current understanding of leucine-rich repeat structure at the primary, secondary, tertiary and quaternary levels and discusses specific examples from recently determined three-dimensional structures.

Condition monitoring of a motor-operated valve using estimated motor torque

International Nuclear Information System (INIS)

Chai, Jangbom; Kang, Shinchul; Park, Sungkeun; Hong, Sungyull; Lim, Chanwoo

2004-01-01

This paper is concerned with the development of data analysis methods to be used in on-line monitoring and diagnosis of Motor-Operated Valves (MOVs) effectively and accurately. The technique to be utilized includes the electrical measurements and signal processing to estimate electric torque of induction motors, which are attached to most of MOV systems. The estimated torque of an induction motor is compared with the directly measured torque using a torque cell in various loading conditions including the degraded voltage conditions to validate the estimating scheme. The accuracy of the estimating scheme is presented. The advantages of the estimated torque signatures are reviewed over the currently used ones such as the current signature and the power signature in several respects: accuracy, sensitivity, resolution and so on. Additionally, the estimated torque methods are suggested as a good way to monitor the conditions of MOVs with higher accuracy. (author)

Analysis of nature of brazed joints fracture under operating conditions

International Nuclear Information System (INIS)

Orlov, A.V.; Gura, P.M.

1985-01-01

Technique establishing causes leading to brazed joint fracture in pressure boundary components, operating under heavy conditions of high temperature and corrosive medium is described. Some cases of tube brazed joint fractures in a superheater of 12Kh1MF and 08Kh18N10T steels are considered. The attention is paid on using metallography for determination of mechanical or corrosion fracture properties. The diagram is developed permitting to take into account the interrelation between the fracture area in the given zone and its strength

Leaching Studies on ACR-1000{sup R} Fuel Under Reactor Operating Conditions

Energy Technology Data Exchange (ETDEWEB)

Sunder, S. [Atomic Energy of Canada Limited, Fuel and Fuel Channel Safety Branch, Chalk River, Ontario, K0J 1J0 (Canada)

2009-06-15

ACR-1000{sup R} is the latest nuclear power reactor being developed by AECL. The ACR-1000 fuel uses a modified CANFLEX{sup R} fuel bundle that contains low-enriched uranium and pellets of burnable neutron absorbers (BNA) in a central element. Dysprosium and gadolinium are used as the burnable neutron absorbers and are present as oxides in a 'fully-stabilized' zirconia matrix. The BNA material in the centre element is designed to limit the coolant void reactivity of the reactor core during postulated loss-of-coolant accidents. As part of the ACR-1000 fuel development, the stability of the BNA material under conditions associated with defects of the Zircaloy sheathing of the BNA central element has been investigated. The results of these tests can be used to demonstrate the phase stability and leaching behaviour of the ACR-1000 fuel under reactor operating conditions. The samples were disks, about 3-4 mm thick, obtained from BNA pellets and Candu fuel (natural uranium UO{sub 2}) pellets (the UO{sub 2} measurements provide a reference point). Leaching tests were carried out in light water at 325 deg. C, above the maximum coolant temperature in an ACR-1000 fuel channel during normal operating conditions (319 deg. C). This temperature also bounds the maximum operating temperature for the current Candu reactors (311 deg. C). The initial pH of the solution (measured at room temperature) used in the leaching tests was 10.3. The leach rates were determined by monitoring the amount of metals leached into solutions. Leaching tests were also carried out with BNA pellet samples in the presence of Zr-2.5%Nb pressure tube coupons to determine the effects, if any, of the presence of pressure tube material on leach rates. Other leaching tests with BNA pellet samples and UO{sub 2} pellets were conducted at 80 deg. C to study the effects of temperature on the leach rates. The temperature of 80 deg. C was selected as representative of typical shutdown temperatures

Installation of PMV Operation Program in DDC Controller and Air Conditioning Control Using PMV Directly as Set Point

Science.gov (United States)

Haramoto, Ken-Ichi

In general, air conditioning control in a building is operated mainly by indoor air temperature control. Although the operators of the machine in the building accepted a claim for indoor air temperature presented by the building inhabitants, the indoor conditions have been often too cool or warm. Therefore, in an attempt to create better thermal environments, the author paid attention to the PMV that is a thermal comfort index. And then, the possibility of air conditioning control using the PMV directly as the set point was verified by employing actual equipment in an air conditioning testing room and an office building. Prior to the execution of this control, the operation program of the PMV was installed in a DDC controller for the air conditioning control. And information from indoor sensors and so on was inputted to the controller, and the computed PMV was used as the feedback variable.

Recursion Of Binary Space As A Foundation Of Repeatable Programs

Directory of Open Access Journals (Sweden)

Jeremy Horne

2006-10-01

Full Text Available Every computation, including recursion, is based on natural philosophy. Our world may be expressed in terms of a binary logical space that contains functions that act simultaneously as objects and processes (operands and operators. This paper presents an outline of the results of research about that space and suggests routes for further inquiry. Binary logical space is generated sequentially from an origin in a standard coordinate system. At least one method exists to show that each of the resulting 16 functions repeats itself by repeatedly forward-feeding outputs of a function operating over two others as new operands of the original function until the original function appears as an output, thus behaving as an apparent homeostatic automaton. As any space of any dimension is composed of one or more of these functions, so the space is recursive, as well. Semantics gives meaning to recursive structures, computer programs and fundamental constituents of our universe being two examples. Such thoughts open inquiry into larger philosophical issues as free will and determinism.

Cost-effectiveness analysis of repeat fine-needle aspiration for thyroid biopsies read as atypia of undetermined significance.

Science.gov (United States)

Heller, Michael; Zanocco, Kyle; Zydowicz, Sara; Elaraj, Dina; Nayar, Ritu; Sturgeon, Cord

2012-09-01

The 2007 National Cancer Institute (NCI) conference on Thyroid Fine-Needle Aspiration (FNA) introduced the category atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS). Repeat FNA in 3 to 6 months was recommended for low-risk patients. Compliance with these recommendations has been suboptimal. We hypothesized that repeat FNA would be more effective than diagnostic lobectomy, with decreased costs and improved rates of cancer detection. Cost-effectiveness analysis was performed in which we compared diagnostic lobectomy with repeat FNA. A Markov model was developed. Outcomes and probabilities were identified from literature review. Third-party payer costs were estimated in 2010 US dollars. Outcomes were weighted by use of the quality-of-life utility factors, yielding quality-adjusted life years (QALYs). Monte Carlo simulation and sensitivity analysis were used to examine the uncertainty of probability, cost, and utility estimates. The diagnostic lobectomy strategy cost $8,057 and produced 23.99 QALYs. Repeat FNA cost $2,462 and produced 24.05 QALYs. Repeat FNA was dominant until the cost of FNA increased to $6,091. Dominance of the repeat FNA strategy was not sensitive to the cost of operation or the complication rate. The NCI recommendations for repeat FNA regarding follow-up of AUS/FLUS results are cost-effective. Improving compliance with these guidelines should lead to less overall costs, greater quality of life, and fewer unnecessary operations. Copyright © 2012 Mosby, Inc. All rights reserved.

An investigation of safety aspects of operating the end-shields in a brittle condition

International Nuclear Information System (INIS)

Seth, V.K.; Patwardhan, V.M.

1975-01-01

Published data on radiation embrittlement of 3.5% Ni steels (material for RAPP-1, RAPP-2 and MAPP-1 end shields - with charpy V notch value of 2.074 gm at -101 0 C) indicates that the nil ductility transition temperature rise would be of the order of 205 0 C to 260 0 C at the end of 30 year reactor life, against earlier figure of around 120 0 C. Surveillance programme on radiation embrittlement of the end-shields is being conducted to get an idea of the actual condition of the material at any required time. A study has been made to investigate safety aspects of operating the end shields in 'Brittle condition' of the material under the presently designed operating conditions. This study is based on the concept of crack arrest approach (employing fracture analysis diagram; FAD and linear elastic fracture mechanics (using possible correlation between Ksub(Ic) and CVN values). (author)

Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

Science.gov (United States)

Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

2014-02-01

The Gd5Ge2Si2 alloy and the off-stoichiometric Ni50Mn35In15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd5Ge2Si2 and Ni50Mn35In15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

International Nuclear Information System (INIS)

Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

2014-01-01

The Gd 5 Ge 2 Si 2 alloy and the off-stoichiometric Ni 50 Mn 35 In 15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd 5 Ge 2 Si 2 and Ni 50 Mn 35 In 15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis

Reactivity variation's analysis in nuclear propulsion considering the operational real conditions requirements

International Nuclear Information System (INIS)

Pires, Leonardo Paredes; Santos, Rubens Souza dos; Lapa, Marcelo Franklin

2015-01-01

The work presented in this paper highlights the need for the study to determine the reactivity variation ramps needed and possible to meet the real operational conditions required by a nuclear submarine in this several operating phases. In accordance with the operational needs and necessary maneuvers in certain tactical situations, large power variations in the propulsion are demanded. As these sudden and severe changes in propulsion come from the thermal power of nuclear origin, the operation of the nuclear island has to know what kind of answers and criticality variations are necessary to meet each demand speed required. It should be noted that these criticality inserts are conditioned, not only by the propulsion needs, but fundamentally by the imperative need to ensure the core integrity and the chain reaction sustainability considering the phenomenons and complex effects, nonlinear and retro-fed involved. It has to be determined what is the past and required time for each criticality insertion is perceived as motor power. Considering the highlighted aspects, this article concludes and indicates to its end, the need to establish a base operating transitional agenda, according to the naval combat doctrine, to be tested and analyzed under the aspects and peculiarities of kinetic reactors, with the purpose of being generated the appropriate criticality curves for each real need and their respective times of anticipated action. (author)

Reactivity variation's analysis in nuclear propulsion considering the operational real conditions requirements

Energy Technology Data Exchange (ETDEWEB)

Pires, Leonardo Paredes; Santos, Rubens Souza dos; Lapa, Marcelo Franklin, E-mail: leonardo_paredes@icloud.com, E-mail: lapa@ien.gov.br, E-mail: rsantos@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

2015-07-01

The work presented in this paper highlights the need for the study to determine the reactivity variation ramps needed and possible to meet the real operational conditions required by a nuclear submarine in this several operating phases. In accordance with the operational needs and necessary maneuvers in certain tactical situations, large power variations in the propulsion are demanded. As these sudden and severe changes in propulsion come from the thermal power of nuclear origin, the operation of the nuclear island has to know what kind of answers and criticality variations are necessary to meet each demand speed required. It should be noted that these criticality inserts are conditioned, not only by the propulsion needs, but fundamentally by the imperative need to ensure the core integrity and the chain reaction sustainability considering the phenomenons and complex effects, nonlinear and retro-fed involved. It has to be determined what is the past and required time for each criticality insertion is perceived as motor power. Considering the highlighted aspects, this article concludes and indicates to its end, the need to establish a base operating transitional agenda, according to the naval combat doctrine, to be tested and analyzed under the aspects and peculiarities of kinetic reactors, with the purpose of being generated the appropriate criticality curves for each real need and their respective times of anticipated action. (author)

Revisiting the TALE repeat.

Science.gov (United States)

Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

2014-04-01

Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

Mechanical processes with repeated attenuated impacts

CERN Document Server

Nagaev, R F

1999-01-01

This book is devoted to considering in the general case - using typical concrete examples - the motion of machines and mechanisms of impact and vibro-impact action accompanied by a peculiar phenomenon called "impact collapse". This phenomenon is that after the initial collision, a sequence of repeated gradually quickening collisions of decreasing-to-zero intensity occurs, with the final establishment of protracted contact between the interacting bodies. The initiation conditions of the impact collapse are determined and calculation techniques for the quantitative characteristics of the corresp

All-photonic quantum repeaters

Science.gov (United States)

Azuma, Koji; Tamaki, Kiyoshi; Lo, Hoi-Kwong

2015-01-01

Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories. PMID:25873153

Repeated stressor exposure enhances contextual fear memory in a beta-adrenergic receptor-dependent process and increases impulsivity in a non-beta receptor-dependent fashion.

Science.gov (United States)

Camp, Robert M; Johnson, John D

2015-10-15

Memory formation is promoted by stress via the release of norepinephrine and stimulation of beta-adrenergic receptors (β-ARs). Previous data demonstrate that repeated stressor exposure increases norepinephrine turnover and β-AR signaling within the amygdala, which led to the hypothesis that some stress-induced behavioral changes are likely due to facilitated associative learning. To test this, Fischer rats were exposed to chronic mild stress for four days. On day 5, subjects (including non-stressed controls) were injected with the beta-blocker propranolol or vehicle prior to conditioning in an operant box (animals receive two mild foot shocks) or passive avoidance apparatus (animals received a foot shock upon entry into the dark chamber). Twenty-four hours later, subjects were returned to the operant box for measurement of freezing or returned to the passive avoidance apparatus for measurement of latency to enter the dark chamber. Subjects were also tested in an open field to assess context-independent anxiety-like behavior. Animals exposed to chronic stress showed significantly more freezing behavior in the operant box than did controls, and this exaggerated freezing was blocked by propranolol during the conditioning trial. There was no effect of stress on behavior in the open field. Unexpectedly, retention latency was significantly reduced in subjects exposed to chronic stress. These results indicate that chronic exposure to stress results in complex behavioral changes. While repeated stress appears to enhance the formation of fearful memories, it also results in behavioral responses that resemble impulsive behaviors that result in poor decision-making. Copyright © 2015 Elsevier Inc. All rights reserved.

Conditioning the radioactive oils released from the Cernavoda NPP operation

International Nuclear Information System (INIS)

Popescu, I.; Deneanu, N.; Dulama, M.; Baboiescu, E.

2001-01-01

The radioactive oils released during the Cernavoda NPP operation are lubricating oils used in the primary circuit pumps, hydraulic oils used in the reactor charging machine, as well as, waste turbine oils. The primary cooling circuit is the main way of contamination. This waste contain variable amounts of tritium of activities up to 10 8 Bq/l and relatively small amounts of β/γ emitting radionuclides. The radioactive oils resulting of the heat transport system may contain as much as 1.8 TBq/l of tritium. At INR Pitesti, Department of Radioactive Waste Processing, studies were done concerning the radioactive oils conditioning in concrete. It was found that the minimal compression level required for disposal, of 50 MPa, was exceeded. As consequence, the conditioned waste fulfils the conditions of acceptance provided by the Radioactive Waste National Repository at Baita-Bihor. The main stages of the process are: - dosing the radioactive oil, water and NOFOX9 and NOFOX4 emulsion additives for the 220 l or 80 l barrel; - mixing these ingredients up to reaching the emulsion state; - dosing the cement and lime; - adding the enhancing silicate and shaking the mixture to get a homogeneous matrix; - closing the barrel; - conditioning the 80 l barrel within the 220 l container. The production capacity is of 5 to 8 barrels/shift

Assessment of neutron skyshine near unmodified Accumulator Debuncher storage rings under Mu2e operational conditions

Energy Technology Data Exchange (ETDEWEB)

Cossairt, J.Donald; /Fermilab

2010-12-01

Preliminary plans for providing the proton beam needed by the proposed Mu2e experiment at Fermilab will require the transport of 8 GeV protons to the Accumulator/Debuncher where they be processed into an intensity and time structure useful for the experiment. The intensities involved are far greater that those encountered with antiprotons of the same kinetic energy in the same beam enclosures under Tevatron Collider operational conditions, the operating parameters for which the physical facilities of the Antiproton Source were designed. This note explores some important ramifications of the proposed operation for radiation safety and demonstrates the need for extensive modifications of significant portions of the shielding of the Accumulator Debuncher storage rings; notably that underneath the AP Service Buildings AP10, AP30, and AP50. While existing shielding is adequate for the current operating mode of the Accumulator/Debuncher as part of the Antiproton Source used in the Tevatron Collider program, without significant modifications of the shielding configuration in the Accumulator/Debuncher region and/or beam loss control systems far more effective than seen in most applications at Fermilab, the proposed operational mode for Mu2e is not viable for the following reasons: 1. Due to skyshine alone, under normal operational conditions large areas of the Fermilab site would be exposed to unacceptable levels of radiation where most of the Laboratory workforce and some members of the general public who regularly visit Fermilab would receive measurable doses annually, contrary to workforce, public, and DOE expectations concerning the As Low as Reasonably Achievable (ALARA) principle. 2. Under normal operational conditions, a sizeable region of the Fermilab site would also require fencing due to skyshine. The size of the areas involved would likely invite public inquiry about the significant and visible enlargement of Fermilab's posted radiological areas. 3. There

Simulation of gas turbines operating in off-design condition

Energy Technology Data Exchange (ETDEWEB)

Walter, Arnaldo [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mail: walter@fem.unicamp.br

2000-07-01

In many countries thermal power plants based on gas turbines have been the main option for new investment into the electric system due to their relatively high efficiency and low capital cost. Cogeneration systems based on gas turbines have also been an important option for the electric industry. Feasibility studies of power plants based on gas turbine should consider the effect of atmospheric conditions and part-load operation on the machine performance. Doing this, an off-design procedure is required. A G T off-design simulation procedure is described in this paper. Ruston R M was used to validate the simulation procedure that, general sense, presents deviations lower than 2.5% in comparison to manufacturer's data. (author)

Impacts of operating conditions and solution chemistry on osmotic membrane structure and performance

KAUST Repository

Wong, Mavis C.Y.; Martinez, Kristina; Ramon, Guy Z.; Hoek, Eric M.V.

2012-01-01

Herein, we report on changes in the performance of a commercial cellulose triacetate (CTA) membrane, imparted by varied operating conditions and solution chemistries. Changes to feed and draw solution flow rate did not significantly alter the CTA membrane's water permeability, salt permeability, or membrane structural parameter when operated with the membrane skin layer facing the draw solution (PRO-mode). However, water and salt permeability increased with increasing feed or draw solution temperature, while the membrane structural parameter decreased with increasing draw solution, possibly due to changes in polymer intermolecular interactions. High ionic strength draw solutions may de-swell the CTA membrane via charge neutralization, which resulted in lower water permeability, higher salt permeability, and lower structural parameter. This observed trend was further exacerbated by the presence of divalent cations which tends to swell the polymer to a greater extent. Finally, the calculated CTA membrane's structural parameter was lower and less sensitive to external factors when operated in PRO-mode, but highly sensitive to the same factors when the skin layer faced the feed solution (FO-mode), presumably due to swelling/de-swelling of the saturated porous substructure by the draw solution. This is a first attempt aimed at systematically evaluating the changes in performance of the CTA membrane due to operating conditions and solution chemistry, shedding new insight into the possible advantages and disadvantages of this material in certain applications. © 2011 Elsevier B.V.

Impacts of operating conditions and solution chemistry on osmotic membrane structure and performance

KAUST Repository

Wong, Mavis C.Y.

2012-02-01

Herein, we report on changes in the performance of a commercial cellulose triacetate (CTA) membrane, imparted by varied operating conditions and solution chemistries. Changes to feed and draw solution flow rate did not significantly alter the CTA membrane\\'s water permeability, salt permeability, or membrane structural parameter when operated with the membrane skin layer facing the draw solution (PRO-mode). However, water and salt permeability increased with increasing feed or draw solution temperature, while the membrane structural parameter decreased with increasing draw solution, possibly due to changes in polymer intermolecular interactions. High ionic strength draw solutions may de-swell the CTA membrane via charge neutralization, which resulted in lower water permeability, higher salt permeability, and lower structural parameter. This observed trend was further exacerbated by the presence of divalent cations which tends to swell the polymer to a greater extent. Finally, the calculated CTA membrane\\'s structural parameter was lower and less sensitive to external factors when operated in PRO-mode, but highly sensitive to the same factors when the skin layer faced the feed solution (FO-mode), presumably due to swelling/de-swelling of the saturated porous substructure by the draw solution. This is a first attempt aimed at systematically evaluating the changes in performance of the CTA membrane due to operating conditions and solution chemistry, shedding new insight into the possible advantages and disadvantages of this material in certain applications. © 2011 Elsevier B.V.

Operation condition for continuous anti-solvent crystallization of CBZ-SAC cocrystal considering deposition risk of undesired crystals

Science.gov (United States)

Nishimaru, Momoko; Nakasa, Miku; Kudo, Shoji; Takiyama, Hiroshi

2017-07-01

Crystallization operation of cocrystal production has deposition risk of undesired crystals. Simultaneously, continuous manufacturing processes are focused on. In this study, conditions for continuous cocrystallization considering risk reduction of undesired crystals deposition were investigated on the view point of thermodynamics and kinetics. The anti-solvent cocrystallization was carried out in four-component system of carbamazepine, saccharin, methanol and water. From the preliminary batch experiment, the relationships among undesired crystal deposition, solution composition decided by mixing ratio of solutions, and residence time for the crystals were considered, and then the conditions of continuous experiment were decided. Under these conditions, the continuous experiment was carried out. The XRD patterns of obtained crystals in the continuous experiment showed that desired cocrystals were obtained without undesired crystals. This experimental result was evaluated by using multi-component phase diagrams from the view point of the operation point's movement. From the evaluation, it was found that there is a certain operation condition which the operation point is fixed with time in the specific domain without the deposition risk of undesired single component crystals. It means the possibility of continuous production of cocrystals without deposition risk of undesired crystals was confirmed by using multi-component phase diagrams.

Investigation of the operating conditions to morphology evolution of β-L-glutamic acid during seeded cooling crystallization

Science.gov (United States)

Zhang, Fangkun; Liu, Tao; Huo, Yan; Guan, Runduo; Wang, Xue Z.

2017-07-01

In this paper the effects of operating conditions including cooling rate, initial supersaturation, and seeding temperature were investigated on the morphology evolution of β-L-glutamic acid (β-LGA) during seeded cooling crystallization. Based on the results of in-situ image acquisition of the crystal morphology evolution during the crystallization process, it was found that the crystal products tend to be plate-like or short rod-like under a slow cooling rate, low initial supersaturation, and low seeding temperature. In the opposite, the operating conditions of a faster cooling rate, higher initial supersaturation, and higher seeding temperature tend to produce long rod-like or needle-like crystals, and meanwhile, the length and width of crystal products will be increased together with a wider crystal size distribution (CSD). The aspect ratio of crystals, defined by the crystal length over width measured from in-situ or sample images, was taken as a shape index to analyze the crystal morphologies. Based on comparative analysis of the experimental results, guidelines on these operating conditions were given for obtaining the desired crystal shapes, along with the strategies for obtaining a narrower CSD for better product quality. Experimental verifications were performed to illustrate the proposed guidelines on the operating conditions for seeded cooling crystallization of LGA solution.

Evaluation of operational numerical weather predictions in relation to the prevailing synoptic conditions

Science.gov (United States)

Pytharoulis, Ioannis; Tegoulias, Ioannis; Karacostas, Theodore; Kotsopoulos, Stylianos; Kartsios, Stergios; Bampzelis, Dimitrios

2015-04-01

The Thessaly plain, which is located in central Greece, has a vital role in the financial life of the country, because of its significant agricultural production. The aim of DAPHNE project (http://www.daphne-meteo.gr) is to tackle the problem of drought in this area by means of Weather Modification in convective clouds. This problem is reinforced by the increase of population and the water demand for irrigation, especially during the warm period of the year. The nonhydrostatic Weather Research and Forecasting model (WRF), is utilized for research and operational purposes of DAPHNE project. The WRF output fields are employed by the partners in order to provide high-resolution meteorological guidance and plan the project's operations. The model domains cover: i) Europe, the Mediterranean sea and northern Africa, ii) Greece and iii) the wider region of Thessaly (at selected periods), at horizontal grid-spacings of 15km, 5km and 1km, respectively, using 2-way telescoping nesting. The aim of this research work is to investigate the model performance in relation to the prevailing upper-air synoptic circulation. The statistical evaluation of the high-resolution operational forecasts of near-surface and upper air fields is performed at a selected period of the operational phase of the project using surface observations, gridded fields and weather radar data. The verification is based on gridded, point and object oriented techniques. The 10 upper-air circulation types, which describe the prevailing conditions over Greece, are employed in the synoptic classification. This methodology allows the identification of model errors that occur and/or are maximized at specific synoptic conditions and may otherwise be obscured in aggregate statistics. Preliminary analysis indicates that the largest errors are associated with cyclonic conditions. Acknowledgments This research work of Daphne project (11SYN_8_1088) is co-funded by the European Union (European Regional Development Fund

Magnetic conditioning in superfluid

International Nuclear Information System (INIS)

Caspi, S.

1988-08-01

Improvements in superconducting magnet technology have reduced to a handful the number of training quenches typical of dipole magnets. The number of training quenches in long (17 m) and short (1--2 m) SSC magnets are now about the same (operating at 6.6 tesla and 4.4 K). Yet the steps necessary to totally eliminate training are in the future RandD plans for magnet construction and conductor motion prevention. The accepted hypothesis is that Lorentz forces and poor mechanical properties of superconducting cables are the cause of conductor motion. Conductor motion reduces the stored energy in the cable by converting it into heat. The small amount of heat generated (millijoules) during motion is usually enough to quench the magnet when it is close to short sample. During training, the magnet performance normally improves with the number of quenches. It is not the quench itself that improves magnet performance but rather the fact that once conductor motion has occurred it will probably not repeat itself unless subjected to higher forces. Conditioning is a process that enables the magnet to reduce its stored energy without causing a premature quench. During the conditioning process the magnet is further cooled from its operating temperature of 4.4 K to 1.8 K by converting He I into He II. As a result the magnet is placed in a state where it has excess stability as well as excellent heat transfer capabilities. Although this does not eliminate motion, if the magnet is now cycled to /approximately/10% above its operating field at 4.4 K (which is above short sample) the excess stability should be enough to prevent quenching and reduce the probability of conductor motion and training once the magnet has been warmed back up to its operating temperature of 4.4 K. 3 refs., 5 figs

Magnetic conditioning in superfluid

Energy Technology Data Exchange (ETDEWEB)

Caspi, S.

1988-08-01

Improvements in superconducting magnet technology have reduced to a handful the number of training quenches typical of dipole magnets. The number of training quenches in long (17 m) and short (1--2 m) SSC magnets are now about the same (operating at 6.6 tesla and 4.4 K). Yet the steps necessary to totally eliminate training are in the future RandD plans for magnet construction and conductor motion prevention. The accepted hypothesis is that Lorentz forces and poor mechanical properties of superconducting cables are the cause of conductor motion. Conductor motion reduces the stored energy in the cable by converting it into heat. The small amount of heat generated (millijoules) during motion is usually enough to quench the magnet when it is close to short sample. During training, the magnet performance normally improves with the number of quenches. It is not the quench itself that improves magnet performance but rather the fact that once conductor motion has occurred it will probably not repeat itself unless subjected to higher forces. Conditioning is a process that enables the magnet to reduce its stored energy without causing a premature quench. During the conditioning process the magnet is further cooled from its operating temperature of 4.4 K to 1.8 K by converting He I into He II. As a result the magnet is placed in a state where it has excess stability as well as excellent heat transfer capabilities. Although this does not eliminate motion, if the magnet is now cycled to /approximately/10% above its operating field at 4.4 K (which is above short sample) the excess stability should be enough to prevent quenching and reduce the probability of conductor motion and training once the magnet has been warmed back up to its operating temperature of 4.4 K. 3 refs., 5 figs.

Operant Conditioning Principles in the Treatment of Learning and Behavior Problems with Delinquent Boys

Science.gov (United States)

Bednar, Richard L.; And Others

1970-01-01

This study on operant conditioning showed that both groups showed significant improvement in reading skills from pretest to posttest, but that the reinforced group showed significantly more improvement than the nonreinforced group. (Author)

Final Report - Membranes and MEA's for Dry, Hot Operating Conditions

Energy Technology Data Exchange (ETDEWEB)

Hamrock, Steven J

2011-06-30

The focus of this program was to develop a new Proton Exchange Membrane (PEM) which can operate under hotter, dryer conditions than the state of the art membranes today and integrate it into a Membrane Electrode Assembly (MEA). These MEA's should meet the performance and durability requirements outlined in the solicitation, operating under low humidification conditions and at temperatures ranging from -20ºC to 120ºC, to meet 2010 DOE technical targets for membranes. This membrane should operate under low humidification conditions and at temperatures ranging from -20ºC to 120ºC in order to meet DOE HFCIT 2010 commercialization targets for automotive fuel cells. Membranes developed in this program may also have improved durability and performance characteristics making them useful in stationary fuel cell applications. The new membranes, and the MEA's comprising them, should be manufacturable at high volumes and at costs which can meet industry and DOE targets. This work included: A) Studies to better understand factors controlling proton transport within the electrolyte membrane, mechanisms of polymer degradation (in situ and ex situ) and membrane durability in an MEA; B) Development of new polymers with increased proton conductivity over the range of temperatures from -20ºC to 120ºC and at lower levels of humidification and with improved chemical and mechanical stability; C) Development of new membrane additives for increased durability and conductivity under these dry conditions; D) Integration of these new materials into membranes and membranes into MEA's, including catalyst and gas diffusion layer selection and integration; E) Verification that these materials can be made using processes which are scalable to commercial volumes using cost effective methods; F) MEA testing in single cells using realistic automotive testing protocols. This project addresses technical barriers A (Durability) and C (Performance) from the Fuel Cells section of the

Microstructure degradation of LSM-YSZ cathode in SOFCs operated at various conditions

DEFF Research Database (Denmark)

Liu, Yi-Lin; Thydén, Karl Tor Sune; Chen, Ming

2012-01-01

Systematic microstructural analyses have been carried out on a series of technological SOFCs that went through long-term cell tests with various operating parameters including temperature, current load and time length under current. For the LSM-YSZ cathode, a number of microstructure degradation...... mechanisms have been identified. And it has been observed that different mechanisms dominate the degradation process under different test conditions. The severe cathode degradation at 750 °C operation with high current density is attributed to a loss of the cathode/electrolyte interface stability....... For the cells tested at 850 °C, the interface stability is maintained due to further sintering during cell operation. A cell test lasting for 2 years (17500 h) at 850 °C with a moderate current density (not greater than 1 A/cm2) has shown that the cathode microstructure is fairly robust to the degradation...

Experimental investigations on a common centrifugal pump operating under gas entrainment conditions

Energy Technology Data Exchange (ETDEWEB)

Schäfer, Thomas, E-mail: thomas.schaefer@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (Germany); Neumann, Martin [Technische Universität Dresden, AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering (Germany); Bieberle, André [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (Germany); Hampel, Uwe [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics (Germany); Technische Universität Dresden, AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering (Germany)

2017-05-15

Highlights: • The pump performance has been evaluated for several gas entrainment conditions. • The gas entraining flow regime has a large impact on the pump performance. • High-resolution gamma-ray computed tomography (HireCT) has been applied. • Gas holdup inside the operating impeller has been visualized and quantified. • Gas holdup profiles along selected streamlines have been calculated. - Abstract: This paper presents an experimental study on the effects of additional gas entrainment in centrifugal pumps designed for conveying liquid phases only. The pump performance has been evaluated for several gas entrainment conditions, and for various operational settings of the pump, such as its alignment and the rotational speed of the impeller. As a main performance indicator the impact of entrained gas on the hydraulic power of the pump has been analyzed using experimental data. Additionally, high-resolution gamma-ray computed tomography (HireCT) operated in time-averaged rotation-synchronized scanning mode has been applied to quantify local phase fraction distributions inside the rapidly rotating pump impeller. Based on these quantitative tomographic measurements, gas holdup profiles along selected streamlines have been calculated and gas accumulation areas inside the impeller chambers have been visualized. Thus, various internally accumulated gas holdup patterns have been identified and, eventually, associated with characteristic pump performance behaviors. Moreover, the tomographic measuring method allowed an enhanced gas holdup analysis in specified pump compartments. As a result, the related specific gas and liquid phase holdup profiles have been evaluated.

Experimental investigations on a common centrifugal pump operating under gas entrainment conditions

International Nuclear Information System (INIS)

Schäfer, Thomas; Neumann, Martin; Bieberle, André; Hampel, Uwe

2017-01-01

Highlights: • The pump performance has been evaluated for several gas entrainment conditions. • The gas entraining flow regime has a large impact on the pump performance. • High-resolution gamma-ray computed tomography (HireCT) has been applied. • Gas holdup inside the operating impeller has been visualized and quantified. • Gas holdup profiles along selected streamlines have been calculated. - Abstract: This paper presents an experimental study on the effects of additional gas entrainment in centrifugal pumps designed for conveying liquid phases only. The pump performance has been evaluated for several gas entrainment conditions, and for various operational settings of the pump, such as its alignment and the rotational speed of the impeller. As a main performance indicator the impact of entrained gas on the hydraulic power of the pump has been analyzed using experimental data. Additionally, high-resolution gamma-ray computed tomography (HireCT) operated in time-averaged rotation-synchronized scanning mode has been applied to quantify local phase fraction distributions inside the rapidly rotating pump impeller. Based on these quantitative tomographic measurements, gas holdup profiles along selected streamlines have been calculated and gas accumulation areas inside the impeller chambers have been visualized. Thus, various internally accumulated gas holdup patterns have been identified and, eventually, associated with characteristic pump performance behaviors. Moreover, the tomographic measuring method allowed an enhanced gas holdup analysis in specified pump compartments. As a result, the related specific gas and liquid phase holdup profiles have been evaluated.

Simulation of a boiler in transient operating conditions on a digital computer

International Nuclear Information System (INIS)

Micheau, P.; Dahan, G.; Naudin, P.

1974-01-01

Resolving a more general problem, studied for Electricite de France, the mathematical model of the boiler of a nuclear power plant was determined for transient and steady state operating conditions. This gas-water heat exchanger is of counter-flow type. The boundary conditions considered for the fluids are: pressure, mass-flow, and temperature at the inlet, and pressure at the outlet. The two passes gas and water are assumed to be monodimensional, and the separating wall to be so thin that it is not necessary to take into account the temperature drop across it. In the energy equation for the gas, the terms of pressure with respect to position were neglected and also the terms of kinetic energy. The following assumptions were considered for the water pass: the pressure is uniform troughout the boiler, the shear stress at the interface between liquid and vapour is negligible, throughout the boiling zone, the heat exchange coefficient is uniform. The set of equations which forms the model has been resolved by a discretization method. The characteristic magnitudes for the fluids were defined at the boundaries of the meshes, the temperatures of the wall are those in the centre of the meshes. At any time, the model allows the determination of the characteristic magnitudes of the two fluids and the walls, starting from the boundary conditions which vary with time, in a finite number of points. On the gas side, the velocities may cancel themselves at and change direction. On the water steam side, the flow must have a unique direction. Satisfying results concerning some operating conditions have been obtained [fr

Analysis of unknown cause subarachnoid hemorrhage with repeated negative angiogram

International Nuclear Information System (INIS)

Fujii, Mutsumi; Takasato, Yoshio; Masaoka, Hiroyuki; Ohta, Yoshihisa; Hayakawa, Takanori; Honma, Masato

2006-01-01

Seven hundred and fifty five cases of acute non-traumatic subarachnoid hemorrhage (SAH) were admitted to the department of neurosurgery of our hospital from July, 1995 to March, 2004. In 555 patients cerebral angiography was conducted but initial angiography was negative in 30 patients. Except 10 general condition poor patients, in 20 initial angiogram-negative patients were undergone repeated angiography. The cause of SAH could not be demonstrated in 13 cases. The SAH in perimesencephalic and non-perimesencephalic cisturns was seen in 7 and 6 cases, respectively. Occipital and/or neck pain on admission was statistically more common among patients with perimesencephalic SAH than those with non-perimesencephalic SAH (p=0.029), and the prognosis of perimesencephalic SAH was good. We conclude that repeat angiography should not be recommended in patients with perimesencephalic SAH. Patients with non-perimesencephalic SAH had a higher rate of complication. In the non-perimesencephalic group, 3 patients developed hydrocephalus and 3 patients had vasospasm, which were found by repeated angiography. Therefore, repeated angiography is recommended for better clinical outcome by early detection and management of serious complications in this group of patients. (author)

Analysis of winter weather conditions and their potential impact on wind farm operations

Science.gov (United States)

Novakovskaia, E.; Treinish, L. A.; Praino, A.

2009-12-01

Severe weather conditions have two primary impacts on wind farm operations. The first relates to understanding potential damage to the turbines themselves and what actions are required to mitigate the effects. The second is recognizing what conditions may lead to a full or partial shutdown of the wind farm with sufficient lead time to determine the likely inability to meet energy generation committments. Ideally, wind forecasting suitable for wind farm operations should be of sufficient fidelity to resolve features within the boundary layer that lead to either damaging conditions or useful power generation. Given the complexity of the site-specific factors that effect the boundary layer at the scale of typical land-based wind farm locations such as topography, vegetation, land use, soil conditions, etc., which may vary with turbine design and layout within the farm, enabling reliable forecasts of too little or too much wind is challenging. A potential solution should involve continuous updates of alert triggering criteria through analysis of local wind patterns and probabilistic risk assessment for each location. To evaluate this idea, we utilize our operational mesoscale prediction system, dubbed “Deep Thunder”, developed at the IBM Thomas J. Watson Research Center. In particular, we analyze winter-time near-surface winds in upstate New York, where four similar winds farms are located. Each of these farms were built at roughly the same time and utilize similar turbines. Given the relative uncertainty associated with numerical weather prediction at this scale, and the difference in risk assessment due to the two primary impacts of severe weather, probabilistic forecasts are a prerequisite. Hence, we have employed ensembles of weather scenarios, which are based on the NCAR WRF-ARW modelling system. The set of ensemble members was composed with variations in the choices of physics and parameterization schemes, and source of background fields for initial

High-speed flow visualization in a pump-turbine under off-design operating conditions

International Nuclear Information System (INIS)

Hasmatuchi, V; Roth, S; Botero, F; Avellan, F; Farhat, M

2010-01-01

The flow hydrodynamics in a low specific speed radial pump-turbine reduced scale model is experimentally investigated under off-design operating conditions in generating mode. Wall pressure measurements, in the stator, synchronized with high-speed flow visualizations in the vaneless space between the impeller and the guide vanes using air bubbles injection are performed. When starting from the best efficiency point and increasing the runner speed, a significant increase of the pressure fluctuations is observed mainly in channels between wicket gates. The spectral analysis shows a rise of one stall cell, rotating with about 70% of the impeller frequency, at runaway, which further increases as the zero discharge condition is approached. Then a specific image processing technique is detailed and applied to create a synthetic instantaneous view of the flow pattern on the entire guide vanes circumference for an operating point in turbine-brake mode, where backflow and vortices accompany the stall passage.

Durability study and lifetime prediction of baseline proton exchange membrane fuel cell under severe operating conditions

Energy Technology Data Exchange (ETDEWEB)

Marrony, M.; Quenet, S.; Aslanides, A. [European Institute for Energy Research, Emmy-Noether Strasse 11, 76131 Karlsruhe (Germany); Barrera, R.; Ginocchio, S.; Montelatici, L. [Edison, Via Giorgio La Pira 2, 10028 Trofarello (Italy)

2008-08-01

Comparative studies of mechanical and electrochemical properties of Nafion{sup registered} - and sulfonated polyetheretherketone polymer-type membranes are carried out under severe fuel cell conditions required by industrials, within stationary and cycling electric load profiles. These membranes are proposed to be used in PEM between 70 and 90 C as fluorinated or non-fluorinated baseline membranes, respectively. Thus, though the performance of both membranes remains suitable, Nafion{sup registered} backbone brought better mechanical properties and higher electrochemical stabilities than sulfonated polyetheretherketone backbone. The performance stability and the mechanical strength of the membrane-electrode assembly were shown to be influenced by several intrinsic properties of the membrane (e.g., thermal pre-treatment, thickness) and external conditions (fuel cell operating temperature, relative humidity). Finally, a lifetime prediction for membranes under stationary conditions is proposed depending on the operation temperature. At equivalent thicknesses (i.e. 50 {mu}m), Nafion{sup registered} membranes were estimated able to operate into the 80-90 C range while sulfonated polyetheretherketone would be limited into the 70-80 C range. This approach brings baseline information about the capability of these types of polymer electrolyte membrane under fuel cell critical operations. Finally, it is revealed as a potential tool for the selection of the most promising advanced polymers for the ensuing research phase. (author)

Optimization of Fuel Cell System Operating Conditions for Fuel Cell Vehicles

OpenAIRE

Zhao, Hengbing; Burke, Andy

2008-01-01

Proton Exchange Membrane fuel cell (PEMFC) technology for use in fuel cell vehicles and other applications has been intensively developed in recent decades. Besides the fuel cell stack, air and fuel control and thermal and water management are major challenges in the development of the fuel cell for vehicle applications. The air supply system can have a major impact on overall system efficiency. In this paper a fuel cell system model for optimizing system operating conditions was developed wh...

First experience in operating the population of the condition databases for the CMS experiment

International Nuclear Information System (INIS)

De Gruttola, Michele; Paolucci, Pierluigi; Di Guida, Salvatore; Glege, Frank; Innocente, Vincenzo; Schlatter, Dieter; Futyan, David; Govi, Giacomo; Pierro, Antonio

2010-01-01

Reliable population of the condition databases is critical for the correct operation of the online selection as well as of the offline reconstruction and analysis of data. We will describe here the system put in place in the CMS experiment to populate the database and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The system, designed for high flexibility to cope with very different data sources, uses POOL-ORA technology in order to store data in an object format that best matches the object oriented paradigm for C++ programming language used in the CMS offline software. In order to ensure consistency among the various subdetectors, a dedicated package, PopCon (Populator of Condition Objects), is used to store data online. The data are then automatically streamed to the offline database hence immediately accessible offline worldwide. This mechanism was intensively used during 2008 in the test-runs with cosmic rays. The experience of this first months of operation will be discussed in detail.

Low-Normal FMR1 CGG Repeat Length: Phenotypic Associations

Directory of Open Access Journals (Sweden)

Marsha eMailick

2014-09-01

Full Text Available This population-based study investigates genotype-phenotype correlations of low-normal CGG repeats in the fragile X mental retardation 1 (FMR1 gene. FMR1 plays an important role in brain development and function, and encodes FMRP (fragile X mental retardation protein, an RNA-binding protein that regulates protein synthesis impacting activity-dependent synaptic development and plasticity. Most past research has focused on CGG premutation expansions (41 to 200 CGG repeats and on fragile X syndrome (200+ CGG repeats, with considerably less attention on the other end of the spectrum of CGG repeats. Using existing data, older adults with 23 or fewer CGG repeats (2 SDs below the mean were compared with age-peers who have normal numbers of CGGs (24-40 with respect to cognition, mental health, cancer, and having children with disabilities. Men (n = 341 with an allele in the low-normal range and women (n = 46 with two low-normal alleles had significantly more difficulty with their memory and ability to solve day to day problems. Women with both FMR1 alleles in the low-normal category had significantly elevated odds of feeling that they need to drink more to get the same effect as in the past. These women also had two and one-half times the odds of having had breast cancer and four times the odds of uterine cancer. Men and women with low-normal CGGs had higher odds of having a child with a disability, either a developmental disability or a mental health condition. These findings are in line with the hypothesis that there is a need for tight neuronal homeostatic control mechanisms for optimal cognitive and behavioral functioning, and more generally that low numbers as well as high numbers of CGG repeats may be problematic for health.

The Other Shoe: An Early Operant Conditioning Chamber for Pigeons.

Science.gov (United States)

Sakagami, Takayuki; Lattal, Kennon A

2016-05-01

We describe an early operant conditioning chamber fabricated by Harvard University instrument maker Ralph Gerbrands and shipped to Japan in 1952 in response to a request of Professor B. F. Skinner by Japanese psychologists. It is a rare example, perhaps the earliest still physically existing, of such a chamber for use with pigeons. Although the overall structure and many of the components are similar to contemporary pigeon chambers, several differences are noted and contrasted to evolutionary changes in this most important laboratory tool in the experimental analysis of behavior. The chamber also is testimony to the early internationalization of behavior analysis.

A knowledge based operator support system for emergency conditions in nuclear power plants

International Nuclear Information System (INIS)

Venkatesh Babu, C.; Subramanium, K.

1992-01-01

The control centres of the operating Indian nuclear power plants contain a large number of indicators and controls spread over many panels. In the event of onset of an emergency condition, there results a profusion of information, both numeric and symbolic. The operator may succumb to an information and cognitive overload that may be compounded by a lack of knowledge. The failure to apply knowledge and reasoning to solve an operational problem can lead to human error, which has been a major contributing factor in nuclear accidents. From the viewpoint of Artificial Intelligence, human error occurs if the operational problem requires computing resources that exceed human capabilities. The application of Artificial Intelligence, particularly expert systems, to nuclear power plant control room activities has considerable potential to reduce operator error and improve safety and reliability. The purpose of this paper is to discuss an investigative study of the feasibility of developing an operator support system incorporating Artificial Intelligence techniques. An information processing model of such a system, herein designated as Knowledge Based Operator Support System - KBOSS, employing expert systems technology, has been developed. The features of this system are described, and issues involved in its development are discussed. (author). 2 refs., 5 figs., 1 tab

Design Criteria, Operating Conditions, and Nickel-Iron Hydroxide Catalyst Materials for Selective Seawater Electrolysis.

Science.gov (United States)

Dionigi, Fabio; Reier, Tobias; Pawolek, Zarina; Gliech, Manuel; Strasser, Peter

2016-05-10

Seawater is an abundant water resource on our planet and its direct electrolysis has the advantage that it would not compete with activities demanding fresh water. Oxygen selectivity is challenging when performing seawater electrolysis owing to competing chloride oxidation reactions. In this work we propose a design criterion based on thermodynamic and kinetic considerations that identifies alkaline conditions as preferable to obtain high selectivity for the oxygen evolution reaction. The criterion states that catalysts sustaining the desired operating current with an overpotential seawater-mimicking electrolyte. The catalyst was synthesized by a solvothermal method and the activity, surface redox chemistry, and stability were tested electrochemically in alkaline and near-neutral conditions (borate buffer at pH 9.2) and under both fresh seawater conditions. The Tafel slope at low current densities is not influenced by pH or presence of chloride. On the other hand, the addition of chloride ions has an influence in the temporal evolution of the nickel reduction peak and on both the activity and stability at high current densities at pH 9.2. Faradaic efficiency close to 100 % under the operating conditions predicted by our design criteria was proven using in situ electrochemical mass spectrometry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Measurement and analysis of micropore aeration system's oxygenating ability under operation condition in waste water treatment plant].

Science.gov (United States)

Wu, Yuan-Yuan; Zhou, Xiao-Hong; Shi, Han-Chang; Qiu, Yong

2013-01-01

Using the aeration pool in the fourth-stage at Wuxi Lucun Waste Water Treatment Plant (WWTP) as experimental setup, off-gas method was selected to measure the oxygenating ability parameters of micropore aerators in a real WWTP operating condition and these values were compared with those in fresh water to evaluate the performance of the micropore aerators. Results showed that the micropore aerators which were distributed in different galleries of the aeration pool had significantly different oxygenating abilities under operation condition. The oxygenating ability of the micropore aerators distributed in the same gallery changed slightly during one day. Comparing with the oxygenating ability in fresh water, it decreased a lot in the real aeration pool, in more details, under the real WWTP operating condition, the values of oxygen transfer coefficient K(La) oxygenation capacity OC and oxygen utilization E(a) decreased by 43%, 57% and 76%, respectively.

Tevatron serial data repeater system

International Nuclear Information System (INIS)

Ducar, R.J.

1981-01-01

A ten megabit per second serial data repeater system has been developed for the 6.28km Tevatron accelerator. The repeaters are positioned at each of the thirty service buildings and accommodate control and abort system communications as well as distribution of the Tevatron time and energy clocks. The repeaters are transparent to the particular protocol of the transmissions. Serial data are encoded locally as unipolar two volt signals employing the self-clocking Manchester Bi-Phase code. The repeaters modulate the local signals to low-power bursts of 50 MHz rf carrier for the 260m transmission between service buildings. The repeaters also demodulate the transmission and restructure the data for local utilization. The employment of frequency discrimination techniques yields high immunity to the characteristic noise spectrum

Effect of operating conditions in soil aquifer treatment on the removals of pharmaceuticals and personal care products

Energy Technology Data Exchange (ETDEWEB)

He, Kai, E-mail: hekai@urban.env.kyoto-u.ac.jp; Echigo, Shinya; Itoh, Sadahiko

2016-09-15

Soil aquifer treatment (SAT) is an alternative advanced treatment for wastewater reclamation, and it has the potential to control micropollutants including pharmaceuticals and personal care products (PPCPs). However, the relationship of operating conditions in SAT and removals of micropollutants was not clear. In this study, the effects of operating conditions on the removals of PPCPs were evaluated by using lab-scale columns and plant pilot-scale reactors under different operating conditions. Firstly, weathered granite soil (WGS), standard sand (SAND) and Toyoura standard sand (TS) have different soil characteristics such as total organic carbon (TOC) and cation exchange capacity (CEC). In the columns with these packing materials, the removals of carboxylic analgesics and antilipidemics were effective regardless packing materials. The removals of antibiotics were more effective in WGS than in TS and SAND, indicating high TOC and CEC enhance the sorption in SAT. Secondly, with the extension of hydraulic retention time (HRT), the removals of sulfamethoxazole, acetaminophen, crotamiton, and antipyrine were improved in WGS columns, and adaptable biodegradation for moderately removable PPCPs was formed. Thirdly, the removal efficiencies of sulfamethoxazole and crotamiton were higher in the WGS column under vadose condition than in the WGS column under saturated condition, because of aerobic condition in WGS column under vadose condition. Though long HRT and vadose condition had positive influence on the removals of several PPCPs such as sulfamethoxazole, WGS column with an HRT of 7 days under saturated condition removed most PPCPs. - Highlights: • Soil organic matter and cation exchange capacity enhanced the removals of antibiotics in SAT. • A hydraulic retention time (HRT) of 7 days was sufficient for the removals of most PPCPs. • The removals of most selected PPCPs were similar under vadose and saturated conditions. • Vadose condition contributed to the

The Effect of the Operating Conditions on the Apparent Viscosity of Crude Palm Oil During Oil Clarification

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Sulaiman Al-Zuhair, Mirghani I. Ahmed and Yousif A. Abakr

2012-10-01

Full Text Available This paper discusses the apparent viscosity of crude palm oil, using rotary viscometer, under different boundary conditions. It was experimentally shown that the apparent viscosity of palm oil drops with increasing of the shear rate and the temperature.  However, the effect of temperature on the viscosity tends to fade at temperatures beyond 80 oC.  A correlation between the apparent viscosity of crude palm oil and the operating conditions was developed. This correlation can be used in design of crude palm oil settlers and in determining the optimum operating conditions.Key Words:  Crude palm oil, apparent viscosity, shear rate, modelling, separation 

The study of operating an air conditioning system using Maisotsenko-Cycle

Science.gov (United States)

Khan, Mohammad S.; Tahan, Sami; Toufic El-Achkar, Mohamad; Abou Jamus, Saleh

2018-03-01

The project aims to design and build an air conditioning system that runs on the Maisotsenko cycle. The system is required to condition and cool down ambient air for a small residential space with the reduction in the use of electricity and eliminating the use of commercial refrigerants. This project can operate at its optimum performance in remote areas like oil diggers and other projects that run in the desert or any site that would not have a very high relative humidity level. The Maisotsenko cycle is known as the thermodynamic concept that captures energy from the air by using the psychometric renewable energy available in the latent heat in water evaporating in air. The heat and mass exchanger design was based on choosing a material that would-be water resistant and breathable, which was found to be layers of cardboard placed on top of each other and thus creating channels for air to pass through. Aiming for this design eliminates any high power electrical equipment such as compressors, condensers and evaporators that would be used in an AC system with the exception of a 600 W blower and a 10 W fan, thus making it a more environmentally friendly project. Moreover, the project is limited by the ambient temperature and humidity, as the model operates at an optimum when the relative humidity is lower.

Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Lee, Carson Odell; Boe-Hansen, Rasmus; Musovic, Sanin

2014-01-01

Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification...... operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal...... rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot...

Repeat Customer Success in Extension

Science.gov (United States)

Bess, Melissa M.; Traub, Sarah M.

2013-01-01

Four multi-session research-based programs were offered by two Extension specialist in one rural Missouri county. Eleven participants who came to multiple Extension programs could be called "repeat customers." Based on the total number of participants for all four programs, 25% could be deemed as repeat customers. Repeat customers had…

Film repeats in radiology department

International Nuclear Information System (INIS)

Suwan, A. Z.; Al-Shakharah, A. I

1997-01-01

During a one year period, 4910 radiographs of 55780 films were repeated. The objective of our study was to analyse and to classify the causes in order to minimize the repeats, cut the expenses and to provide optimal radiographs for accurate diagnosis. Analysis of the different factors revealed that, 43.6% of film repeats in our service were due to faults in exposure factors, centering comprises 15.9% of the repeats, while too much collimation was responsible for 7.6% of these repeats. All of which can be decreased by awareness and programmed training of technicians. Film blurring caused by patient motion was also responsible for 4.9% for radiographs reexamination, which can be minimized by detailed explanation to the patient and providing the necessary privacy. Fogging of X-Ray films by improper storage or inadequate handling or processing faults were responsible for 14.5% in repeats in our study. Methods and criteria for proper storage and handling of films were discussed. Recommendation for using modern day-light and laser processor has been high lighted. Artefacts are noticeably high in our cases, due to spinal dresses and frequent usage of precious metals for c osmotic purposes in this part of the world. The repeated films comprise 8.8% of all films We conclude that, the main factor responsible for repeats of up to 81.6% of cases was the technologists, thus emphasizing the importance of adequate training of the technologists. (authors). 15 refs., 9 figs., 1 table

On the improvement of signal repeatability in laser-induced air plasmas

Science.gov (United States)

Zhang, Shuai; Sheta, Sahar; Hou, Zong-Yu; Wang, Zhe

2018-04-01

The relatively low repeatability of laser-induced breakdown spectroscopy (LIBS) severely hinders its wide commercialization. In the present work, we investigate the optimization of LIBS system for repeatability improvement for both signal generation (plasma evolution) and signal collection. Timeintegrated spectra and images were obtained under different laser energies and focal lengths to investigate the optimum configuration for stable plasmas and repeatable signals. Using our experimental setup, the optimum conditions were found to be a laser energy of 250 mJ and a focus length of 100 mm. A stable and homogeneous plasma with the largest hot core area in the optimum condition yielded the most stable LIBS signal. Time-resolved images showed that the rebounding processes through the air plasma evolution caused the relative standard deviation (RSD) to increase with laser energies of > 250 mJ. In addition, the emission collection was improved by using a concave spherical mirror. The line intensities doubled as their RSDs decreased by approximately 25%. When the signal generation and collection were optimized simultaneously, the pulse-to-pulse RSDs were reduced to approximately 3% for O(I), N(I), and H(I) lines, which are better than the RSDs reported for solid samples and showed great potential for LIBS quantitative analysis by gasifying the solid or liquid samples.

Repeat migration and disappointment.

Science.gov (United States)

Grant, E K; Vanderkamp, J

1986-01-01

This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

Associations of emotional arousal, dissociation and symptom severity with operant conditioning in borderline personality disorder.

Science.gov (United States)

Paret, Christian; Hoesterey, Steffen; Kleindienst, Nikolaus; Schmahl, Christian

2016-10-30

Those with borderline personality disorder (BPD) display altered evaluations regarding reward and punishment compared to others. The processing of rewards is basal for operant conditioning. However, studies addressing operant conditioning in BPD patients are rare. In the current study, an operant conditioning task combining learning acquisition and reversal was used. BPD patients and matched healthy controls (HCs) were exposed to aversive and neutral stimuli to assess the influence of emotion on learning. Picture content, dissociation, aversive tension and symptom severity were rated. Error rates were measured. Results showed no group interactions between aversive versus neutral scenes. The higher emotional arousal, dissociation and tension, the worse the acquisition, but not reversal, scores were for BPD patients. Scores from the Borderline Symptom List were associated with more errors in the reversal, but not the acquisition phase. The results are preliminary evidence for impaired acquisition learning due to increased emotional arousal, dissociation and tension in BPD patients. A failure to process punishment in the reversal phase was associated with symptom severity and may be related to neuropsychological dysfunctioning involving the ventromedial prefrontal cortex. Conclusions are limited due to the correlational study design and the small sample size. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Quantum repeated games revisited

International Nuclear Information System (INIS)

Frąckiewicz, Piotr

2012-01-01

We present a scheme for playing quantum repeated 2 × 2 games based on Marinatto and Weber’s approach to quantum games. As a potential application, we study the twice repeated Prisoner’s Dilemma game. We show that results not available in the classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games proposed by Iqbal and Toor. We point out the drawbacks that make their results unacceptable. (paper)

Extraction of sunflower oil by twin screw extruder: screw configuration and operating condition effects

Energy Technology Data Exchange (ETDEWEB)

Kartika, I.A. [FATETA-IPB, Bogor (Indonesia). Department of Agroindustrial Technology; Pontalier, P.Y.; Rigal, L. [Laboratoire de Chimie Agro-Industrielle, UMR 1010 INRA/INP-ENSIACET, Toulouse (France)

2006-12-15

The objective of this study was to investigate the screw configuration allowing oil extraction from sunflower seeds with a twin-screw extruder. Experiments were conducted using a co-rotating twin-screw extruder. Five screw profiles were examined to define the best performance (oil extraction yield, specific mechanical energy and oil quality) by studying the influence of operating conditions, barrel temperature, screw speed and feed rate. Generally, the position and spacing between two reversed screw elements affected oil extraction yield. An increase of oil extraction yield was observed as the reversed screw elements were moved with increased spacing between two elements and with smaller pitch elements. In addition, oil extraction yield increased as barrel temperature, screw speed and feed rate were decreased. Highest oil extraction yield (85%) with best cake meal quality (residual oil content lower than 13%) was obtained under operating conditions of 120 {sup o}C, 75 rpm and 19 kg/h. Furthermore, the operating parameters influenced energy input. A decrease in barrel temperature and feed rate followed by an increase in screw speed increased energy input, particularly specific mechanical energy input. Effect of the operating parameters on oil quality was less important. In all experiments tested, the oil quality was very good. The acid value was below 2 mg of KOH/g of oil and total phosphorus content was low, below 100 mg/kg. (author)

Perioperative Challenges in Repeat Bladder Exstrophy Repair - Case Report

Directory of Open Access Journals (Sweden)

Otu Enenyi Etta

2015-07-01

Full Text Available Bladder exstrophy is a rare congenital malformation. It presents as leakage of urine in the anterior abdominal wall following defects in midline anterior abdominal wall skin and bladder. We report the use of combined general anaesthesia and caudal epidural analgesia in a 4yr old boy for repeat bladder exstrophy repair. Problems of prolonged surgery and the challenges of pain and sedation management in the post operative period are discussed.

Feeding Behavior of Aplysia: A Model System for Comparing Cellular Mechanisms of Classical and Operant Conditioning

Science.gov (United States)

Baxter, Douglas A.; Byrne, John H.

2006-01-01

Feeding behavior of Aplysia provides an excellent model system for analyzing and comparing mechanisms underlying appetitive classical conditioning and reward operant conditioning. Behavioral protocols have been developed for both forms of associative learning, both of which increase the occurrence of biting following training. Because the neural…

Ways to improve the environmental conditions of their buses in operation on passenger routes of cities

Directory of Open Access Journals (Sweden)

Melnychuk S.V.

2017-04-01

Full Text Available The results of studies on operational and environmental parameters buses used on bus routes Zhitomir city. It uses statistical methods for determining the intensity of traffic, passenger traffic and ecology in traffic. To assess the environmental chosen stop with the greatest intensity of traffic, which is the probability of accumulation of pollution transport emissions that exceed permissible limits. Calculation of environmental pollution emission route for vehicles made stops street «Str. Hundreds of Heaven» «CUM», «vul. Hlibna» on the main trunk street Kievska. Results obtained environmental field experiments compared with the data defined calculation methods, based on the proposed use appropriate operational vehicles. The conclusions that indicate the seriousness of the problem and the urgency to address it. The system of environmental safety and road safety in Zhitomir requires significant improvements due to the increased quantities bus vehicles plying city routes. Recommendations to improve the ecological condition of intersections can be developed through the optimization of traffic using buses with environmentally improved operating parameters. Keywords: environmental and operational parameters; ecological safety; environmental assessment; intensity of traffic; passenger traffic; environmental conditions; operation; bus choice; stop.

STRUCTURAL ANALYSIS OF RAILWAYS BOLSTER-BEAM UNDER COMMERCIAL OPERATION CONDITIONS: OVER-TRACTION AND OVER-BRAKING

Directory of Open Access Journals (Sweden)

Ronald M. MARTINOD

2016-06-01

Full Text Available The conditions for the operation of railway systems are closely related to the increase of the commercial demand; as a consequence, the performance of the structural elements of railways changes. The present paper focuses on a study of the structural behaviour of bolster-beams under commercial operation conditions of railway systems, specifically in the dynamic conditions generated in events of over-traction and over-braking on the vehicle running. The proposed work is constructed based on the following phases: (i analysis of the kinematics of the vehicle; (ii development of numerical models, a model based on the multibody theory, and a Finite Elements model; (iii development of experimental field tests; and (iv development of simulations for a detailed analysis of the structural behaviour for a study of the strain distribution in the main bolster-beam. This study is applied to a particular case of a railway system that provides commercial service to passengers.

Ups and Downs: Mechanisms of Repeat Instability in the Fragile X-Related Disorders

Directory of Open Access Journals (Sweden)

Xiao-Nan Zhao

2016-09-01

Full Text Available The Fragile X-related disorders (FXDs are a group of clinical conditions resulting from the expansion of a CGG/CCG-repeat tract in exon 1 of the Fragile X mental retardation 1 (FMR1 gene. While expansions of the repeat tract predominate, contractions are also seen with the net result being that individuals can show extensive repeat length heterogeneity in different tissues. The mechanisms responsible for expansion and contraction are still not well understood. This review will discuss what is known about these processes and current evidence that supports a model in which expansion arises from the interaction of components of the base excision repair, mismatch repair and transcription coupled repair pathways.

Effects of management strategies on glucocorticoids and behavior in Indian rhinoceros (Rhinoceros unicornis): translocation and operant conditioning.

Science.gov (United States)

Capiro, Jonnie M; Stoops, Monica A; Freeman, Elizabeth W; Clawson, Dave; Schook, Mandi W

2014-01-01

The ex situ Indian rhino population experienced a decrease in genetic diversity indicating that the breeding program could possibly benefit from novel reproductive management strategies to ensure population sustainability. We sought to determine how management tools used for reproductive management, specifically translocation and operant conditioning, impact physiological and behavioral measures of welfare in Indian rhinos. First, an adrenocorticotropic hormone challenge performed in an adult male resulted in a 38-fold increase in urinary and a 3.5-fold increase in fecal glucocorticoid metabolites (FGM). Mean and peak FGM differed among three females, but all demonstrated elevated (P operant conditioning to stand during transrectal ultrasound exams were monitored and rhinos differed in their mean and peak FGM concentrations. However, FGM were not different before versus during training or on pasture versus in the barn. One female exhibited more stereotypic behavior during training in the barn than on pasture (P operant conditioning only resulted in minimal changes in behaviors and FGM. © 2014 Wiley Periodicals Inc.

Condition based monitoring, diagnosis and maintenance on operating equipments of a hydraulic generator unit

International Nuclear Information System (INIS)

Liu, X T; Feng, F Z; Si, A W

2012-01-01

According to performance characteristics of operating equipments in a hydraulic generator unit (HGU), the relative techniques on condition monitoring and fault diagnosis (CMFD) are introduced in this paper, especially the key technologies are emphasized, such as equipment monitoring, expert system (ES), intelligent diagnosis and condition based maintenance (CBM). Meanwhile, according to the instructor on CBM proposed by State electric power corporation, based on integrated mode, the main steps on implementation of CBM are discussed in this paper.

Application-Ready Expedited MODIS Data for Operational Land Surface Monitoring of Vegetation Condition

Directory of Open Access Journals (Sweden)

Jesslyn F. Brown

2015-12-01

Full Text Available Monitoring systems benefit from high temporal frequency image data collected from the Moderate Resolution Imaging Spectroradiometer (MODIS system. Because of near-daily global coverage, MODIS data are beneficial to applications that require timely information about vegetation condition related to drought, flooding, or fire danger. Rapid satellite data streams in operational applications have clear benefits for monitoring vegetation, especially when information can be delivered as fast as changing surface conditions. An “expedited” processing system called “eMODIS” operated by the U.S. Geological Survey provides rapid MODIS surface reflectance data to operational applications in less than 24 h offering tailored, consistently-processed information products that complement standard MODIS products. We assessed eMODIS quality and consistency by comparing to standard MODIS data. Only land data with known high quality were analyzed in a central U.S. study area. When compared to standard MODIS (MOD/MYD09Q1, the eMODIS Normalized Difference Vegetation Index (NDVI maintained a strong, significant relationship to standard MODIS NDVI, whether from morning (Terra or afternoon (Aqua orbits. The Aqua eMODIS data were more prone to noise than the Terra data, likely due to differences in the internal cloud mask used in MOD/MYD09Q1 or compositing rules. Post-processing temporal smoothing decreased noise in eMODIS data.

Study of Optimal Perimetric Testing in Children (OPTIC: Feasibility, Reliability and Repeatability of Perimetry in Children.

Directory of Open Access Journals (Sweden)

Dipesh E Patel

Full Text Available To investigate feasibility, reliability and repeatability of perimetry in children.A prospective, observational study recruiting 154 children aged 5-15 years, without an ophthalmic condition that affects the visual field (controls, identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24-2 FAST, Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability.Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests. Examiner rated reliability was 'good' in 125 (81.2% children for Goldmann, 100 (64.9% for Octopus and 98 (63.6% for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey, p<0.001. No significant differences were found for any of the three test strategies when examining initial and follow-up data outputs (Bland-Altman plots, n=43, suggesting good test repeatability, although the sample size may preclude detection of a small learning effect.Feasibility and reliability of formal perimetry in children improves with age. By the age of 9 years, all the strategies used here were highly feasible and reliable. Clinical assessment of the visual field is achievable in children as young as 5 years, and should be considered where visual field loss is suspected. Since Goldmann perimetry is the most effective strategy in children aged 5-8 years and this perimeter is no longer available, further

Fatigue crack growth characteristics of nitrogen-alloyed type 347 stainless under operating conditions of a pressurized water reactor

Energy Technology Data Exchange (ETDEWEB)

Min, Ki Deuk; Hong, Seok Min; Kim, Dae Whan; Lee, Bong Sang [Korea Atomic Energy Research Institute, Nuclear Materials Safety Research Division, Daejeon (Korea, Republic of); Kim, Seon Jin [Hanyang University, Division of materials science and engineering, Seoul (Korea, Republic of)

2017-06-15

The fatigue crack growth behavior of Type 347 (S347) and Type 347N (S347N) stainless steel was evaluated under the operating conditions of a pressurized water reactor (PWR). These two materials showed different fatigue crack growth rates (FCGRs) according to the changes in dissolved oxygen content and frequency. Under the simulated PWR conditions for normal operation, the FCGR of S347N was lower than that of S347 and insensitive to the changes in PWR water conditions. The higher yield strength and better corrosion resistance of the nitrogen-alloyed Type 347 stainless steel might be a main cause of slower FCGR and more stable properties against changes in environmental conditions.

Readout Distance Enhancement of the Passive Wireless Multi-Parameter Sensing System Using a Repeater Coil

Directory of Open Access Journals (Sweden)

Lifeng Wang

2018-01-01

Full Text Available A repeater coil is used to extend the detection distance of a passive wireless multi-parameter sensing system. The passive wireless sensing system has the ability of simultaneously monitoring three parameters by using backscatter modulation together with channel multiplexing. Two different repeater coils are designed and fabricated for readout distance enhancement of the sensing system: one is a PCB (printed circuit board repeater coil, and the other is a copper wire repeater coil. Under the conditions of fixed voltage and adjustable voltage, the maximum readout distance of the sensing system with and without a repeater coil is measured. Experimental results show that larger power supply voltage can help further increase the readout distance. The maximum readout distance of the sensing system with a PCB repeater coil has been extended 2.3 times, and the one with a copper wire repeater coil has been extended 3 times. Theoretical analysis and experimental results both indicate that the high Q factor repeater coil can extend the readout distance more. With the copper wire repeater coil as well as a higher power supply voltage, the passive wireless multi-parameter sensing system finally achieves a maximum readout distance of 13.5 cm.

Development of a quantitative evaluation method for non-technical skills preparedness of operation teams in nuclear power plants to deal with emergency conditions

International Nuclear Information System (INIS)

Yim, Ho Bin; Kim, Ar Ryum; Seong, Poong Hyun

2013-01-01

Highlights: ► We selected important non-technical skills for emergency conditions in NPPs. ► We proposed an evaluation method for the selected non-technical skills. ► We conducted two sets of training, 9 experiments each, with real plant operators. ► Teams showed consistent non-technical skills preparedness with changing scenarios. ► Non-technical skills preparedness gives plausible explanations why teams fail tasks. -- Abstract: Many statistical results from safety reports tell that human related errors are the dominant influencing factor on the safe operation of power plants. Fortunately, training operators for the technical and non-technical skills can prevent many types of human errors. In this study, four important non-technical skills in safety critical industries – medical, aviation, and nuclear – were selected to describe behaviors of operation teams in emergency conditions of nuclear power plants (NPPs): communication, leadership, situation awareness, and decision-making skills. Also, preparedness of the non-technical skills was defined, and a quantification method of those skills called NoT-SkiP (Non-Technical Skills Preparedness) was developed to represent ‘how well operation teams are prepared to deal with emergency conditions’ in the non-technical skills aspect by analyzing monitoring-control patterns and a verbal protocol. Two case studies were conducted to validate the method. The first case was applied to Loss of Coolant Accident (LOCA) and Steam Generator Tube Rupture (SGTR) training. Independent variables were scenario, training repetition, and members. Relative values of the NoT-SkiP showed a consistent trend with changing scenarios. However, when training was repeated with the same scenario, NoT-SkiP values of some team were changed. It was supposed that leaders of some teams exerted their knowledge acquired from the previous training and gave up thoroughness of using procedures. When members especially who play a dominant role

Development of a quantitative evaluation method for non-technical skills preparedness of operation teams in nuclear power plants to deal with emergency conditions

Energy Technology Data Exchange (ETDEWEB)

Yim, Ho Bin; Kim, Ar Ryum [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

2013-02-15

Highlights: ► We selected important non-technical skills for emergency conditions in NPPs. ► We proposed an evaluation method for the selected non-technical skills. ► We conducted two sets of training, 9 experiments each, with real plant operators. ► Teams showed consistent non-technical skills preparedness with changing scenarios. ► Non-technical skills preparedness gives plausible explanations why teams fail tasks. -- Abstract: Many statistical results from safety reports tell that human related errors are the dominant influencing factor on the safe operation of power plants. Fortunately, training operators for the technical and non-technical skills can prevent many types of human errors. In this study, four important non-technical skills in safety critical industries – medical, aviation, and nuclear – were selected to describe behaviors of operation teams in emergency conditions of nuclear power plants (NPPs): communication, leadership, situation awareness, and decision-making skills. Also, preparedness of the non-technical skills was defined, and a quantification method of those skills called NoT-SkiP (Non-Technical Skills Preparedness) was developed to represent ‘how well operation teams are prepared to deal with emergency conditions’ in the non-technical skills aspect by analyzing monitoring-control patterns and a verbal protocol. Two case studies were conducted to validate the method. The first case was applied to Loss of Coolant Accident (LOCA) and Steam Generator Tube Rupture (SGTR) training. Independent variables were scenario, training repetition, and members. Relative values of the NoT-SkiP showed a consistent trend with changing scenarios. However, when training was repeated with the same scenario, NoT-SkiP values of some team were changed. It was supposed that leaders of some teams exerted their knowledge acquired from the previous training and gave up thoroughness of using procedures. When members especially who play a dominant role

Repeatability of the Oxford Foot Model in children with foot deformity.

Science.gov (United States)

McCahill, Jennifer; Stebbins, Julie; Koning, Bart; Harlaar, Jaap; Theologis, Tim

2018-03-01

The Oxford Foot Model (OFM) is a multi-segment, kinematic model developed to assess foot motion. It has previously been assessed for repeatability in healthy populations. To determine the OFM's reliability for detecting foot deformity, it is important to know repeatability in pathological conditions. The aim of the study was to assess the repeatability of the OFM in children with foot deformity. Intra-tester repeatability was assessed for 45 children (15 typically developing, 15 hemiplegic, 15 clubfoot). Inter-tester repeatability was assessed in the clubfoot population. The mean absolute differences between testers (clubfoot) and sessions (clubfoot and hemiplegic) were calculated for each of 15 clinically relevant, kinematic variables and compared to typically developing children. Children with clubfoot showed a mean difference between visits of 2.9° and a mean difference between raters of 3.6° Mean absolute differences were within one degree for the intra and inter-rater reliability in 12/15 variables. Hindfoot rotation, forefoot/tibia abduction and forefoot supination were the most variable between testers. Overall the clubfoot data were less variable than the typically developing population. Children with hemiplegia demonstrated slightly higher differences between sessions (mean 4.1°), with the most reliable data in the sagittal plane, and largest differences in the transverse plane. The OFM was designed to measure different types of foot deformity. The results of this study show that it provides repeatable results in children with foot deformity. To be distinguished from measurement artifact, changes in foot kinematics as a result of intervention or natural progression over time must be greater than the repeatability reported here. Copyright © 2018 Elsevier B.V. All rights reserved.

Study on operational condition of electro-decontamination by computer simulation

International Nuclear Information System (INIS)

Amamoto, Ippei; Sato, Koji; Kawabe, Akihiro; Fujita, Reiko; Terai, Takayuki

2005-01-01

The molten-salt electro-decontamination method can be taken up as adecontamination method for contaminated metal systems generated in the reprocessing using the fluoride volatility method, etc. This method makes a small amount of secondary waste and is able to construct a small-size process in which a critical state is easily controlled. It can be further expected that an electrolytic current penetrates inside contaminated substances of complex shape. In this report, an appropriate operational condition was theoretically obtained by the simulation on the applicability of this method to decontamination of metal materials, and it was confirmed by a fundamental testing that the simulation result is reasonable. (M.H.)

Influence of operating conditions on the air gasification of dry refinery sludge in updraft gasifier

International Nuclear Information System (INIS)

Ahmed, R; Sinnathambi, C M

2013-01-01

In the present work, details of the equilibrium modeling of dry refinery sludge (DRS) are presented using ASPEN PLUS Simulator in updraft gasifier. Due to lack of available information in the open journal on refinery sludge gasification using updraft gasifier, an evaluate for its optimum conditions on gasification is presented in this paper. For this purpose a Taguchi Orthogonal array design, statistical software is applied to find optimum conditions for DRS gasification. The goal is to identify the most significant process variable in DRS gasification conditions. The process variables include; oxidation zone temperature, equivalent ratio, operating pressure will be simulated and examined. Attention was focused on the effect of optimum operating conditions on the gas composition of H 2 and CO (desirable) and CO 2 (undesirable) in terms of mass fraction. From our results and finding it can be concluded that the syngas (H 2 and CO) yield in term of mass fraction favors high oxidation zone temperature and at atmospheric pressure while CO 2 acid gas favor at a high level of equivalent ratio as well as air flow rate favoring towards complete combustion.

Evaluating the potential of gold, silver, and silica nanoparticles to saturate mononuclear phagocytic system tissues under repeat dosing conditions.

Science.gov (United States)

Weaver, James L; Tobin, Grainne A; Ingle, Taylor; Bancos, Simona; Stevens, David; Rouse, Rodney; Howard, Kristina E; Goodwin, David; Knapton, Alan; Li, Xiaohong; Shea, Katherine; Stewart, Sharron; Xu, Lin; Goering, Peter L; Zhang, Qin; Howard, Paul C; Collins, Jessie; Khan, Saeed; Sung, Kidon; Tyner, Katherine M

2017-07-17

As nanoparticles (NPs) become more prevalent in the pharmaceutical industry, questions have arisen from both industry and regulatory stakeholders about the long term effects of these materials. This study was designed to evaluate whether gold (10 nm), silver (50 nm), or silica (10 nm) nanoparticles administered intravenously to mice for up to 8 weeks at doses known to be sub-toxic (non-toxic at single acute or repeat dosing levels) and clinically relevant could produce significant bioaccumulation in liver and spleen macrophages. Repeated dosing with gold, silver, and silica nanoparticles did not saturate bioaccumulation in liver or spleen macrophages. While no toxicity was observed with gold and silver nanoparticles throughout the 8 week experiment, some effects including histopathological and serum chemistry changes were observed with silica nanoparticles starting at week 3. No major changes in the splenocyte population were observed during the study for any of the nanoparticles tested. The clinical impact of these changes is unclear but suggests that the mononuclear phagocytic system is able to handle repeated doses of nanoparticles.

Large eddy simulation of cooling flows in underground subway station according to different PSD operating conditions

Energy Technology Data Exchange (ETDEWEB)

Jang, Yong Jun; Kim, Jin Ho; Park, Sung Huk; Koo, Dong Hoe [Korea Railroad Research Institute, Uiwang (Korea, Republic of)

2015-11-15

Large eddy simulation (LES) method is applied to systematically investigate the cooling fluid flow and the temperature distribution under the operating of air conditioning in the deeply underground subway station. The Shin-Gum-Ho subway station in Seoul which is the 8{sup th} floor and 43.6 m deep is selected for this analysis. The entire station is covered for simulation. The ventilation mode for air conditioning is kept as ordinary state. Different operating conditions for Platform screen door (PSD) are applied. First one is PSD is completely close and second one is PSD is regularly open and close which imitate the actual circumstances in the platform. The ventilation diffusers are modeled as 95 square shapes in the lobby and 222 squares in the platform. The temperature variations and flow behaviors are numerically simulated after operating of air conditioning for the whole station and the calculated results are compared with experimental data. LES method solves the momentum and thermal equations. Werner-Wengle wall law is applied to viscous sub layers for near wall resolution. The total grid numbers are 7.5 million and the whole domain is divided to 22 blocks. Multi blocks are computed in parallel using MPI. The results show the temperature difference in the platform between PSD-close and PSD-regularly open and close cases is 3-4 .deg. C.

Large eddy simulation of cooling flows in underground subway station according to different PSD operating conditions

International Nuclear Information System (INIS)

Jang, Yong Jun; Kim, Jin Ho; Park, Sung Huk; Koo, Dong Hoe

2015-01-01

Large eddy simulation (LES) method is applied to systematically investigate the cooling fluid flow and the temperature distribution under the operating of air conditioning in the deeply underground subway station. The Shin-Gum-Ho subway station in Seoul which is the 8"t"h floor and 43.6 m deep is selected for this analysis. The entire station is covered for simulation. The ventilation mode for air conditioning is kept as ordinary state. Different operating conditions for Platform screen door (PSD) are applied. First one is PSD is completely close and second one is PSD is regularly open and close which imitate the actual circumstances in the platform. The ventilation diffusers are modeled as 95 square shapes in the lobby and 222 squares in the platform. The temperature variations and flow behaviors are numerically simulated after operating of air conditioning for the whole station and the calculated results are compared with experimental data. LES method solves the momentum and thermal equations. Werner-Wengle wall law is applied to viscous sub layers for near wall resolution. The total grid numbers are 7.5 million and the whole domain is divided to 22 blocks. Multi blocks are computed in parallel using MPI. The results show the temperature difference in the platform between PSD-close and PSD-regularly open and close cases is 3-4 .deg. C

Repeat-mediated epigenetic dysregulation of the FMR1 gene in the fragile X-related disorders.

Science.gov (United States)

Usdin, Karen; Kumari, Daman

2015-01-01

The fragile X-related disorders are members of the Repeat Expansion Diseases, a group of genetic conditions resulting from an expansion in the size of a tandem repeat tract at a specific genetic locus. The repeat responsible for disease pathology in the fragile X-related disorders is CGG/CCG and the repeat tract is located in the 5' UTR of the FMR1 gene, whose protein product FMRP, is important for the proper translation of dendritic mRNAs in response to synaptic activation. There are two different pathological FMR1 allele classes that are distinguished only by the number of repeats. Premutation alleles have 55-200 repeats and confer risk of fragile X-associated tremor/ataxia syndrome and fragile X-associated primary ovarian insufficiency. Full mutation alleles on the other hand have >200 repeats and result in fragile X syndrome, a disorder that affects learning and behavior. Different symptoms are seen in carriers of premutation and full mutation alleles because the repeat number has paradoxical effects on gene expression: Epigenetic changes increase transcription from premutation alleles and decrease transcription from full mutation alleles. This review will cover what is currently known about the mechanisms responsible for these changes in FMR1 expression and how they may relate to other Repeat Expansion Diseases that also show repeat-mediated changes in gene expression.

Mechanical Alterations Associated with Repeated Treadmill Sprinting under Heat Stress.

Directory of Open Access Journals (Sweden)

Olivier Girard

Full Text Available Examine the mechanical alterations associated with repeated treadmill sprinting performed in HOT (38°C and CON (25°C conditions.Eleven recreationally active males performed a 30-min warm-up followed by three sets of five 5-s sprints with 25-s recovery and 3-min between sets in each environment. Constant-velocity running for 1-min at 10 and 20 km.h-1 was also performed prior to and following sprinting.Mean skin (37.2±0.7 vs. 32.7±0.8°C; P<0.001 and core (38.9±0.2 vs. 38.8±0.3°C; P<0.05 temperatures, together with thermal comfort (P<0.001 were higher following repeated sprinting in HOT vs. CON. Step frequency and vertical stiffness were lower (-2.6±1.6% and -5.5±5.5%; both P<0.001 and contact time (+3.2±2.4%; P<0.01 higher in HOT for the mean of sets 1-3 compared to CON. Running distance per sprint decreased from set 1 to 3 (-7.0±6.4%; P<0.001, with a tendency for shorter distance covered in HOT vs. CON (-2.7±3.4%; P = 0.06. Mean vertical (-2.6±5.5%; P<0.01, horizontal (-9.1±4.4%; P<0.001 and resultant ground reaction forces (-3.0±2.8%; P<0.01 along with vertical stiffness (-12.9±2.3%; P<0.001 and leg stiffness (-8.4±2.7%; P<0.01 decreased from set 1 to 3, independently of conditions. Propulsive power decreased from set 1 to 3 (-16.9±2.4%; P<0.001, with lower propulsive power values in set 2 (-6.6%; P<0.05 in HOT vs. CON. No changes in constant-velocity running patterns occurred between conditions, or from pre-to-post repeated-sprint exercise.Thermal strain alters step frequency and vertical stiffness during repeated sprinting; however without exacerbating mechanical alterations. The absence of changes in constant-velocity running patterns suggests a strong link between fatigue-induced velocity decrements during sprinting and mechanical alterations.

Mechanical Alterations Associated with Repeated Treadmill Sprinting under Heat Stress

Science.gov (United States)

Brocherie, Franck; Morin, Jean-Benoit; Racinais, Sébastien; Millet, Grégoire P.; Périard, Julien D.

2017-01-01

Purpose Examine the mechanical alterations associated with repeated treadmill sprinting performed in HOT (38°C) and CON (25°C) conditions. Methods Eleven recreationally active males performed a 30-min warm-up followed by three sets of five 5-s sprints with 25-s recovery and 3-min between sets in each environment. Constant-velocity running for 1-min at 10 and 20 km.h-1 was also performed prior to and following sprinting. Results Mean skin (37.2±0.7 vs. 32.7±0.8°C; P<0.001) and core (38.9±0.2 vs. 38.8±0.3°C; P<0.05) temperatures, together with thermal comfort (P<0.001) were higher following repeated sprinting in HOT vs. CON. Step frequency and vertical stiffness were lower (-2.6±1.6% and -5.5±5.5%; both P<0.001) and contact time (+3.2±2.4%; P<0.01) higher in HOT for the mean of sets 1–3 compared to CON. Running distance per sprint decreased from set 1 to 3 (-7.0±6.4%; P<0.001), with a tendency for shorter distance covered in HOT vs. CON (-2.7±3.4%; P = 0.06). Mean vertical (-2.6±5.5%; P<0.01), horizontal (-9.1±4.4%; P<0.001) and resultant ground reaction forces (-3.0±2.8%; P<0.01) along with vertical stiffness (-12.9±2.3%; P<0.001) and leg stiffness (-8.4±2.7%; P<0.01) decreased from set 1 to 3, independently of conditions. Propulsive power decreased from set 1 to 3 (-16.9±2.4%; P<0.001), with lower propulsive power values in set 2 (-6.6%; P<0.05) in HOT vs. CON. No changes in constant-velocity running patterns occurred between conditions, or from pre-to-post repeated-sprint exercise. Conclusions Thermal strain alters step frequency and vertical stiffness during repeated sprinting; however without exacerbating mechanical alterations. The absence of changes in constant-velocity running patterns suggests a strong link between fatigue-induced velocity decrements during sprinting and mechanical alterations. PMID:28146582

Analysis of flow induced valve operation and pressure wave propagation for single and two-phase flow conditions

International Nuclear Information System (INIS)

Nagel, H.

1986-01-01

The flow induced valve operation is calculated for single and two-phase flow conditions by the fluid dynamic computer code DYVRO and results are compared to experimental data. The analysis show that the operational behaviour of the valves is not only dependent on the condition of the induced flow, but also the pipe flow can cause a feedback as a result of the induced pressure waves. For the calculation of pressure wave propagation in pipes of which the operation of flow induced valves has a considerable influence it is therefore necessary to have a coupled analysis of the pressure wave propagation and the operational behaviour of the valves. The analyses of the fast transient transfer from steam to two-phase flow show a good agreement with experimental data. Hence even these very high loads on pipes resulting from such fluid dynamic transients can be calculated realistically. (orig.)

Development of a REBCO HTS magnet for Maglev - repeated bending tests of HTS pancake coils -

Science.gov (United States)

Sugino, Motohikoa; Mizuno, Katsutoshi; Tanaka, Minoru; Ogata, Masafumi

2018-01-01

In the past study, two manufacturing methods were developed that can manufacture pancake coils by using REBCO coated conductors. It was confirmed that the conductors have no electric degradation that caused by the manufacturing method. The durability evaluation tests of the pancake coils were conducted as the final evaluation of the coil manufacturing method in this study. The repeated bending deformation was applied to manufactured pancake coils in the tests. As the results of these tests, it was confirmed that the pancake coils that were manufactured by two methods had the durability for the repeated bending deformation and the coils maintained the appropriate mechanical performance and electric performance. We adopted the fusion bonding method as the coil manufacturing method of the HTS magnet Furthermore, using the prototype pancake coil that was manufactured by the fusion bonding method as a test sample, the repeated bending test under the exited condition was conducted. Thus it was confirmed that the coil manufactured by the fusion bonding method has no degradation of the electricity performance and the mechanical properties even if the repeated bending deformation was applied under the exited condition.

Effect of operating conditions on performance of silica gel-water air-fluidised desiccant cooler

Directory of Open Access Journals (Sweden)

Rogala Zbigniew

2017-01-01

Full Text Available Fluidised desiccant cooling is reported in the literature as an efficient way to provide cooling for air-conditioning purposes. The performance of this technology can be described by electric and thermal Coefficients of Performance (COP and Specific Cooling Power (SCP. In this paper comprehensive theoretical study was carried out in order to assess the effect of operating conditions such as: superficial air velocity, desiccant particle diameter, bed switching time and desiccant filling height on the performance of fluidised desiccant cooler (FDC. It was concluded that FDC should be filled with as small as possible desiccant particles featuring diameters and should not be operated with shorter switching times than optimum. Moreover in order to efficiently run such systems superficial air velocities during adsorption and desorption should be similar. At last substantial effect of desiccant filling height on performance of FDC was presented.

The optimum operating conditions of the phased double-rotor facility at the et-R R-1 reactor. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Naguib, K; Habib, N; Kilany, M; Adib, M [Reactor and Neutron Physics Department, Nuclear Research Center, AEA., Cairo (Egypt); Wahba, M [Dept. of Engineering Physics and Mathematics, Faculty of Engineering, Ain Shams University, Cairo (Egypt)

1996-03-01

The pulsed neutron polyenergetic thermal beam at ET-R R-1 is produced by a phased double-rotor facility. One of the rotors has two diametrically opposite curved slots, while the second is designed to operate as a rotating collimator, the dimensions of the phased rotating collimator are selected to match the curved slot rotor. The calculated collimator transmissions at different operating conditions are found to be in good agreement with the experimental ones. The optimum operating conditions of double-rotor facility are deduced. The calculations were carried out using a computer programme RCOL. The RCOL was designed in Fortran-77 to operate on PCs. 6 figs.

The optimum operating conditions of the phased double-rotor facility at the et-R R-1 reactor. Vol. 2

International Nuclear Information System (INIS)

Naguib, K.; Habib, N.; Kilany, M.; Adib, M.; Wahba, M.

1996-01-01

The pulsed neutron polyenergetic thermal beam at ET-R R-1 is produced by a phased double-rotor facility. One of the rotors has two diametrically opposite curved slots, while the second is designed to operate as a rotating collimator, the dimensions of the phased rotating collimator are selected to match the curved slot rotor. The calculated collimator transmissions at different operating conditions are found to be in good agreement with the experimental ones. The optimum operating conditions of double-rotor facility are deduced. The calculations were carried out using a computer programme RCOL. The RCOL was designed in Fortran-77 to operate on PCs. 6 figs

Repeatability of visual acuity measurement.

Science.gov (United States)

Raasch, T W; Bailey, I L; Bullimore, M A

1998-05-01

This study investigates features of visual acuity chart design and acuity testing scoring methods which affect the validity and repeatability of visual acuity measurements. Visual acuity was measured using the Sloan and British Standard letter series, and Landolt rings. Identifiability of the different letters as a function of size was estimated, and expressed in the form of frequency-of-seeing curves. These functions were then used to simulate acuity measurements with a variety of chart designs and scoring criteria. Systematic relationships exist between chart design parameters and acuity score, and acuity score repeatability. In particular, an important feature of a chart, that largely determines the repeatability of visual acuity measurement, is the amount of size change attributed to each letter. The methods used to score visual acuity performance also affect repeatability. It is possible to evaluate acuity score validity and repeatability using the statistical principles discussed here.

Investigation of a High Head Francis Turbine at Runaway Operating Conditions

Directory of Open Access Journals (Sweden)

Chirag Trivedi

2016-03-01

Full Text Available Hydraulic turbines exhibit total load rejection during operation because of high fluctuations in the grid parameters. The generator reaches no-load instantly. Consequently, the turbine runner accelerates to high speed, runaway speed, in seconds. Under common conditions, stable runaway is only reached if after a load rejection, the control and protection mechanisms both fail and the guide vanes cannot be closed. The runner life is affected by the high amplitude pressure loading at the runaway speed. A model Francis turbine was used to investigate the consequences at the runaway condition. Measurements and simulations were performed at three operating points. The numerical simulations were performed using standard k-ε, k-ω shear stress transport (SST and scale-adaptive simulation (SAS models. A total of 12.8 million hexahedral mesh elements were created in the complete turbine, from the spiral casing inlet to the draft tube outlet. The experimental and numerical analysis showed that the runner was subjected to an unsteady pressure loading up to three-times the pressure loading observed at the best efficiency point. Investigates of unsteady pressure pulsations at the vaneless space, runner and draft tube are discussed in the paper. Further, unsteady swirling flow in the blade passages was observed that was rotating at a frequency of 4.8-times the runaway runner angular speed. Apart from the unsteady pressure loading, the development pattern of the swirling flow in the runner is discussed in the paper.

Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

Science.gov (United States)

Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

2015-11-01

This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

Performance of diagonal control structures at different operating conditions for polymer electrolyte membrane fuel cells

Energy Technology Data Exchange (ETDEWEB)

Serra, Maria; Husar, Attila; Feroldi, Diego; 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)

2006-08-25

This work is focused on the selection of operating conditions in polymer electrolyte membrane fuel cells. It analyses efficiency and controllability aspects, which change from one operating point to another. Specifically, several operating points that deliver the same amount of net power are compared, and the comparison is done at different net power levels. The study is based on a complex non-linear model, which has been linearised at the selected operating points. Different linear analysis tools are applied to the linear models and results show important controllability differences between operating points. The performance of diagonal control structures with PI controllers at different operating points is also studied. A method for the tuning of the controllers is proposed and applied. The behaviour of the controlled system is simulated with the non-linear model. Conclusions indicate a possible trade-off between controllability and optimisation of hydrogen consumption. (author)

Evaluation of cable aging degradation based on plant operating condition

International Nuclear Information System (INIS)

Kim, Jong-Seog

2005-01-01

Extending the lifetime of nuclear power plant [(hereafter referred simply as ''NPP'')] is one of the most important concerns in the world nuclear industry. Cables are one of the long live items which have not been considered to be replaced during the design life of NPP. To extend the cable life beyond the design life, we need to prove that the design life is too conservative compared with the actual aging. Condition monitoring is one of the useful ways for evaluating the aging condition of cable. In order to simulate the natural aging in nuclear power plant, a study on accelerated aging needs to be conducted first. In this paper, evaluations of mechanical aging degradation for cable jacket were performed after accelerated aging under the continuous heating and intermittent heating. Contrary to general expectation, the intermittent heating to cable jacket showed low aging degradation, 50% break-elongation and 60% indenter modulus, compared with continuous heating. With the plant maintenance period of 1 month after every 12 or 18 months operation, we can easily deduce that the life time of cable jacket can be extended much longer than estimated through the general EQ (Environmental Qualification) test, which adopts continuous accelerated aging for determining cable life. Therefore, a systematic approach which considers the actual environment condition of nuclear power plant is required for determining the life of cables. (author)

The utility of repeat sestamibi scans in patients with primary hyperparathyroidism after an initial negative scan.

Science.gov (United States)

Krishnamurthy, Vikram D; Sound, Sara; Okoh, Alexis K; Yazici, Pinar; Yigitbas, Hakan; Neumann, Donald; Doshi, Krupa; Berber, Eren

2017-06-01

We analyzed the utility of repeated sestambi scans in patients with primary hyperparathyroidism and its effects on operative referral. We carried out a retrospective review of patients with primary hyperparathyroidism who underwent repeated sestambi scans exclusively within our health system between 1996-2015. Patient demographic, presentation, laboratory, imaging, operative, and pathologic data were reviewed. Univariate analysis with JMP Pro v12 was used to identify factors associated with conversion from an initial negative to a subsequent positive scan. After exclusion criteria (including reoperations), we identified 49 patients in whom 59% (n = 29) of subsequent scans remained negative and 41% (n = 20) converted to positive. Factors associated with an initial negative to a subsequent positive scan included classic presentation and second scans with iodine subtraction (P = .04). Nonsurgeons were less likely to order an iodine-subtraction scan (P < .05). Fewer patients with negative imaging were referred to surgery (33% vs 100%, P = .005), and median time to operation after the first negative scan was 25 months (range 1.4-119). Surgeon-performed ultrasonography had greater sensitivity and positive predictive value than repeated sestamibi scans. Negative sestambi scans decreased and delayed operative referral. Consequently, we identified several process improvement initiatives, including education regarding superior institutional imaging. Combining all findings, we created an algorithm for evaluating patients with primary hyperparathyroidism after initially negative sestamibi scans, which incorporates surgeon-performed ultrasonography. Copyright © 2016 Elsevier Inc. All rights reserved.

Lithium-ion battery dynamic model for wide range of operating conditions

DEFF Research Database (Denmark)

Stroe, Ana-Irina; Stroe, Daniel-Ioan; Swierczynski, Maciej Jozef

2017-01-01

In order to analyze the dynamic behavior of a Lithium-ion (Li-ion) battery and to determine their suitability for various applications, battery models are needed. An equivalent electrical circuit model is the most common way of representing the behavior of a Li-ion battery. There are different...... characterization tests performed for a wide range of operating conditions (temperature, load current and state-of-charge) on a commercial available 13Ah high-power lithium titanate oxide battery cell. The obtained results were used to parametrize the proposed dynamic model of the battery cell. To assess...

A Network-Based Algorithm for Clustering Multivariate Repeated Measures Data

Science.gov (United States)

Koslovsky, Matthew; Arellano, John; Schaefer, Caroline; Feiveson, Alan; Young, Millennia; Lee, Stuart

2017-01-01

The National Aeronautics and Space Administration (NASA) Astronaut Corps is a unique occupational cohort for which vast amounts of measures data have been collected repeatedly in research or operational studies pre-, in-, and post-flight, as well as during multiple clinical care visits. In exploratory analyses aimed at generating hypotheses regarding physiological changes associated with spaceflight exposure, such as impaired vision, it is of interest to identify anomalies and trends across these expansive datasets. Multivariate clustering algorithms for repeated measures data may help parse the data to identify homogeneous groups of astronauts that have higher risks for a particular physiological change. However, available clustering methods may not be able to accommodate the complex data structures found in NASA data, since the methods often rely on strict model assumptions, require equally-spaced and balanced assessment times, cannot accommodate missing data or differing time scales across variables, and cannot process continuous and discrete data simultaneously. To fill this gap, we propose a network-based, multivariate clustering algorithm for repeated measures data that can be tailored to fit various research settings. Using simulated data, we demonstrate how our method can be used to identify patterns in complex data structures found in practice.

Assessment of Radionuclides Release from Inshas LILW Disposal Facility Under Normal and Unusual Operational Conditions

International Nuclear Information System (INIS)

Zaki, A.A.

2008-01-01

Disposing of low and intermediate radioactive waste (LILW) is a big concern for Egypt due to the accumulated waste as a result of past fifty years of peaceful nuclear applications. Assessment of radionuclides release from Inshas LILW disposal facility under normal and unusual operational conditions is very important in order to apply for operation license of the facility. Aqueous release of radionuclides from this disposal facility is controlled by water flow, access of the water to the wasteform, release of the radionuclides from the wasteform, and transport to the disposal facility boundary. In this work, the release of 137 Cs , 6C o, and 90 Sr radionuclides from the Inshas disposal facility was studied under the change of operational conditions. The release of these radio contaminants from the source term to the unsaturated and saturated zones , to groundwater were studied. It was found that the concentration of radionuclides in a groundwater well located 150 m away from the Inshas disposal facility is less than the maximum permissible concentration in groundwater in both cases

Prediction of knock limited operating conditions of a natural gas engine

International Nuclear Information System (INIS)

Soylu, Seref

2005-01-01

Computer models of engine processes are valuable tools for predicting and analyzing engine performance and allow exploration of many engine design alternatives in an inexpensive fashion. In the present work, a zero-dimensional, two zone thermodynamic model was used to determine the knock limited operating conditions of a natural gas engine. Experimentally based burning rate models were used for flame initiation and propagation calculations. A knock model was incorporated with the zero-dimensional model. Comparison of the measured and calculated cylinder pressure data indicated that the model is able to match the measured cylinder pressure data with less than 8% error in magnitudes if the computations are started at the experimental spark timing. The knock predictions agreed with the measurements also. With the established knock model, it is possible not only to investigate whether knock is observed with changing operating and design parameters, but also to evaluate their effects on the maximum possible knock intensity

LHC Beam Dump Design Study - Part III : Off-normal operating conditions

CERN Document Server

Bruno, L; Ross, M; Sala, P

2000-01-01

The LHC beam dump design study has been preliminarily substantiated by energy deposition simulations (Part I) and heat transfer analyses (Part II). The present report is devoted to the abnormal operating conditions induced by a malfunction of the beam diluters. A general approach to the analysis of off-normal operation is presented, which is derived from standard design norms adopted in the nuclear industry. Attention is focused mainly on the carbon core, which is longitudinally split into segments of different density in order to better distribute the deposited energy. The maximum energy density it absorbs decreases by at least 33%, compared to a uniform standard density carbon core. This structure may sustain any partial sweep failure without major damage, up to the ultimate beam intensity and energy. To minimise the risks inherent in a fully unswept beam, a sacrificial graphite mandrel will be placed on the core axis, surrounded by a thick high strength carbon-carbon composite tube. With this arrangement, ...

Experience with fuel damage caused by abnormal conditions in handling and transporting operations

International Nuclear Information System (INIS)

Bailey, W.J.

1983-01-01

Pacific Northwest Laboratory (PNL) conducted a study to determine the expected condition of spent USA light-water reactor (LWR) fuel upon arrival at interim storage or fuel reprocessing facilities or, if fuel is declared a waste, at disposal facilities. Initial findings were described in an earlier PNL paper at PATRAM '80 and in a report. Updated findings are described in this paper, which includes an evaluation of information obtained from the literature and a compilation of cases of known or suspected damage to fuel as a result of handling and/or transporting operations. To date, PNL has evaluated 123 actual cases (98 USA and 25 non-USA). Irradiated fuel was involved in all but 10 of the cases. From this study, it is calculated that the frequency of unusual occurrences involving fuel damage from handling and transporting operations has been low. The damage that did occur was generally minor. The current base of experience with fuel handling and transporting operations indicates that nearly all of these unusual occurrences had only a minor or negligible effect on spent fuel storage facility operations

A thermodynamic approach for selecting operating conditions in the design of reversible solid oxide cell energy systems

Science.gov (United States)

Wendel, Christopher H.; Kazempoor, Pejman; Braun, Robert J.

2016-01-01

Reversible solid oxide cell (ReSOC) systems are being increasingly considered for electrical energy storage, although much work remains before they can be realized, including cell materials development and system design optimization. These systems store electricity by generating a synthetic fuel in electrolysis mode and subsequently recover electricity by electrochemically oxidizing the stored fuel in fuel cell mode. System thermal management is improved by promoting methane synthesis internal to the ReSOC stack. Within this strategy, the cell-stack operating conditions are highly impactful on system performance and optimizing these parameters to suit both operating modes is critical to achieving high roundtrip efficiency. Preliminary analysis shows the thermoneutral voltage to be a useful parameter for analyzing ReSOC systems and the focus of this study is to quantitatively examine how it is affected by ReSOC operating conditions. The results reveal that the thermoneutral voltage is generally reduced by increased pressure, and reductions in temperature, fuel utilization, and hydrogen-to-carbon ratio. Based on the thermodynamic analysis, many different combinations of these operating conditions are expected to promote efficient energy storage. Pressurized systems can achieve high efficiency at higher temperature and fuel utilization, while non-pressurized systems may require lower stack temperature and suffer from reduced energy density.

A paradigm for operant conditioning in blow flies (Phormia terrae novae Robineau-Desvoidy, 1830).

Science.gov (United States)

Sokolowski, Michel B C; Disma, Gérald; Abramson, Charles I

2010-01-01

An operant conditioning situation for the blow fly (Protophormia terrae novae) is described. Individual flies are trained to enter and reenter a hole as the operant response. Only a few sessions of contingent reinforcement are required to increase response rates. When the response is no longer followed by food, the rate of entering the hole decreases. Control procedures revealed that rate of responding is not a simple overall result of feeding or of aging. The flies entered into the hole only if the response was required to obtain the food.

Numerical simulations of the first operational conditions of the negative ion test facility SPIDER

International Nuclear Information System (INIS)

Serianni, G.; Agostinetti, P.; Antoni, V.; Baltador, C.; Chitarin, G.; Marconato, N.; Pasqualotto, R.; Sartori, E.; Toigo, V.; Veltri, P.; Cavenago, M.

2016-01-01

In view of the realization of the negative ion beam injectors for ITER, a test facility, named SPIDER, is under construction in Padova (Italy) to study and optimize production and extraction of negative ions. The present paper is devoted to the analysis of the expected first operations of SPIDER in terms of single-beamlet and multiple-beamlet simulations of the hydrogen beam optics in various operational conditions. The effectiveness of the methods adopted to compensate for the magnetic deflection of the particles is also assessed. Indications for a sequence of the experimental activities are obtained

Estimation of the optimal operating conditions for a radiation chemical neutralization unit

International Nuclear Information System (INIS)

Putilov, A.V.; Kamenetskaya, S.A.; Pshezhetskii, S.Ya.; Kazakov, M.S.; Kudryavtsev, S.L.; Petrukhin, N.V.; Misharin, B.A.; Koneev, V.Z.

1985-01-01

An estimate is made of the effect of the hydrodynamic conditions on the efficiency of foam units for the radiation chemical neutralization of impurities, taking into account the penetrating power of accelerated electrons having various energies. Expressions are obtained for calculating the efficiency of such units with sectionized operation of the chamber and taking account of the effect of incomplete mixing of the products of radiolysis through the height of the foam layer

Analysis of the influence of operating conditions on fouling rates in fired heaters

International Nuclear Information System (INIS)

Morales-Fuentes, A.; Picón-Núñez, M.; Polley, G.T.; Méndez-Díaz, S.

2014-01-01

Fouling due to chemical reaction in preheat trains for the processing of crude oil plays a key role in the operation and maintenance costs and on greenhouse emissions to atmosphere in crude processing plants. A preheat train consists of a set of heat transfer units that provide the crude oil stream the required amount of thermal energy to reach its target temperature either by heat recovery or by direct firing. Fired heaters supply external high temperature heating through the burning of fuel which result in complex heat transfer processes due to the large temperature and pressure changes and vaporization that takes place inside the unit. In this work, a thermo-hydraulic analysis of the performance of fired heaters is carried out through the application of commercial software to solve the mathematical models using finite difference methods; the analysis is applied to the crude side of a vertical fired heater in order to evaluate the impact of process conditions such as throughput and crude inlet temperature (CIT) on the fouling that take place at the early stages of operation. Using a fouling rate model based on thermo-hydraulic parameters, fouling rates are predicted assuming steady state operation and clean conditions. Although variations in process conditions are known to influence fouling rates, little work has been done on the subject. In this work excess air and steam injection are studied as a means to mitigate fouling. Results show that throughput reduction brings about a marked increase in the fouling rates. A decrease in CIT affects only the convection zone and it is found that this effect is negligible. In terms of excess air, it is found that although it affects negatively the heater efficiency it can be used to balance heat transfer between the convection and radiation zone in a way that fouling rates are reduced; however this strategy should be considered right from the design stage. Finally it is observed that steam injection is an effective method

What we have learned about scheduling elective repeat cesarean delivery at term.

Science.gov (United States)

Tita, Alan T N

2016-08-01

The optimal timing of delivery in the setting of various clinical conditions and scenarios remains one of the most common questions for obstetric providers. Over the past 5-10 years, the optimal timing of delivery at term, particularly for elective repeat cesareans, has been the subject of considerable investigation and discussion. There is an increasing consensus that when women opt for an elective repeat cesarean delivery, it should be performed at term rather than preterm. The recent redefinition of the "term" period into early term (37-38 weeks), full-term (39-40 weeks), late term (41 weeks), and post term designations (≥42 weeks) underscores observed heterogeneity in outcomes following delivery at term. The American College of Obstetricians and Gynecologists currently recommends that elective repeat cesarean delivery be performed at full-term. Herein, the available data to support this recommendation regarding timing of elective repeat cesarean delivery are reviewed, including contributions from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units (MFMU) Network. Copyright © 2016. Published by Elsevier Inc.

Experimental studies of solar heat pipe used to operate absorption chiller in conditions of Vietnam

Energy Technology Data Exchange (ETDEWEB)

Hiep, Le Chi [Ho Chi Minh City Univ. of Tech., Ho Chi Minh City (Viet Nam); Quoc, Hoang An [Ho Chi Minh City Univ. of Tech. Education, Ho Chi Minh City (Viet Nam); Hung, Hoang Duong [Danang Univ. of Tech., Danang City (Viet Nam)

2008-07-01

Several models of solar heat pipe have been fabricated and tested. The experiments show that the flat plate model could be used to operate absorption chiller in the climate of southern part of Vietnam. Two main advantages of the selected solar heat pipe are low cost and easy fabrication at local conditions. It is expected that the selected solar heat pipe could attract attention of the community to develop the application of solar energy in Vietnam. Based on the current demand, the paper presents the experimental studies of the first generation of low cost solar heat pipe. The paper also discusses the ability of application of solar air conditioning in Vietnam and recommends the suitable diagram mixing solar energy with other heat source to operate stably the system. (orig.)

High field strength magnetic resonance imaging in paediatric brain tumour surgery--its role in prevention of early repeat resections.

Science.gov (United States)

Avula, Shivaram; Pettorini, Benedetta; Abernethy, Laurence; Pizer, Barry; Williams, Dawn; Mallucci, Conor

2013-10-01

The purpose of this study is to compare the surgical and imaging outcome in children who underwent brain tumour surgery with intention of complete tumour resection, prior to and following the start of intra-operative MRI (ioMRI) service. ioMRI service for brain tumour resection commenced in October 2009. A cohort of patients operated between June 2007 and September 2009 with a pre-surgical intention of complete tumour resection were selected (Group A). A similar number of consecutive cases were selected from a prospective database of patients undergoing ioMRI (Group B). The demographics, imaging, pathology and surgical outcome of both groups were compared. Thirty-six of 47 cases from Group A met the inclusion criterion and 36 cases were selected from Group B; 7 of the 36 cases in Group A had unequivocal evidence of residual tumour on the post-operative scan; 5 (14%) of them underwent repeat resection within 6 months post-surgery. In Group B, ioMRI revealed unequivocal evidence of residual tumour in 11 of the 36 cases following initial resection. In 10 of these 11 cases, repeat resections were performed during the same surgical episode and none of these 11 cases required repeat surgery in the following 6 months. Early repeat resection rate was significantly different between both groups (p = 0.003). Following the advent of ioMRI at our institution, the need for repeat resection within 6 months has been prevented in cases where ioMRI revealed unequivocal evidence of residual tumour.

Pre-operative assessment and post-operative care in elective shoulder surgery.

Science.gov (United States)

Akhtar, Ahsan; Macfarlane, Robert J; Waseem, Mohammad

2013-01-01

Pre-operative assessment is required prior to the majority of elective surgical procedures, primarily to ensure that the patient is fit to undergo surgery, whilst identifying issues that may need to be dealt with by the surgical or anaesthetic teams. The post-operative management of elective surgical patients begins during the peri-operative period and involves several health professionals. Appropriate monitoring and repeated clinical assessments are required in order for the signs of surgical complications to be recognised swiftly and adequately. This article examines the literature regarding pre-operative assessment in elective orthopaedic surgery and shoulder surgery, whilst also reviewing the essentials of peri- and post-operative care. The need to recognise common post-operative complications early and promptly is also evaluated, along with discussing thromboprophylaxis and post-operative analgesia following shoulder surgery.

Final Report - Advanced MEA's for Enhanced Operating Conditions, Amenable to High Volume Manufacture

Energy Technology Data Exchange (ETDEWEB)

Debe, Mark K.

2007-09-30

This report summarizes the work completed under a 3M/DOE contract directed at advancing the key fuel cell (FC) components most critical for overcoming the polymer electrolyte membrane fuel cell (PEMFC) performance, durability & cost barriers. This contract focused on the development of advanced ion exchange membranes & electrocatalysts for PEMFCs that will enable operation under ever more demanding automotive operating conditions & the use high volume compatible processes for their manufacture. Higher performing & more durable electrocatalysts must be developed for PEMFCs to meet the power density & lifetime hours required for FC vehicles. At the same time the amount of expensive Pt catalyst must be reduced to lower the MEA costs. While these two properties are met, the catalyst must be made resistant to multiple degradation mechanisms to reach necessary operating lifetimes. In this report, we present the work focused on the development of a completely new approach to PEMFC electrocatalyts, called nanostructured thin film (NSTF) catalysts. The carbon black supports are eliminated with this new approach which eliminates the carbon corrosion issue. The thin film nature of the catalyst significantly improves its robustness against dissolution & grain growth, preserving the surface area. Also, the activity of the NSTF for oxygen reduction is improved by over 500% compared to dispersed Pt catalyts. Finally, the process for fabricating the NSTF catalysts is consistent with high volume roll-good manufacturing & extremely flexible towards the introduction of new catalyst compositions & structures. This report documents the work done to develop new multi-element NSTF catalysts with properties that exceed pure Pt, that are optimized for use with the membranes discussed below, & advance the state-of-the-art towards meeting the DOE 2010 targets for PEMFC electrocatalysts. The work completed advances the understanding of the NSTF catalyst technology, identifies new NSTF

Fostering repeat donations in Ghana.

Science.gov (United States)

Owusu-Ofori, S; Asenso-Mensah, K; Boateng, P; Sarkodie, F; Allain, J-P

2010-01-01

Most African countries are challenged in recruiting and retaining voluntary blood donors by cost and other complexities and in establishing and implementing national blood policies. The availability of replacement donors who are a cheaper source of blood has not enhanced repeat voluntary donor initiatives. An overview of activities for recruiting and retaining voluntary blood donors was carried out. Donor records from mobile sessions were reviewed from 2002 to 2008. A total of 71,701 blood donations; 45,515 (63.5%) being voluntary donations with 11,680 (25%) repeat donations were collected during the study period. Donations from schools and colleges contributed a steady 60% of total voluntary whilst radio station blood drives increased contribution from 10 to 27%. Though Muslim population is less than 20%, blood collection was above the 30-donation cost-effectiveness threshold with a repeat donation trend reaching 60%. In contrast Christian worshippers provided donations. Repeat donation trends amongst school donors and radio blood drives were 20% and 70% respectively. Repeat donations rates have been variable amongst different blood donor groups in Kumasi, Ghana. The impact of community leaders in propagating altruism cannot be overemphasized. Programs aiming at motivating replacement donors to be repeat donors should be developed and assessed. Copyright 2009 The International Association for Biologicals. All rights reserved.

Effect of operating conditions on the performance of the bubble pump of absorption-diffusion refrigeration cycles

Directory of Open Access Journals (Sweden)

Benhmidene Ali

2011-01-01

Full Text Available The mathematical model will be able to predict the operated condition (required tube diameters, heat input and submergence ratio….. That will result in a successful bubble pump design and hence a refrigeration unit. In the present work a one-dimensional two-fluid model of boiling mixing ammonia-water under constant heat flux is developed. The present model is used to predict the outlet liquid and vapor velocities and pumping ratio for different heat flux input to pump. The influence of operated conditions such as: ammonia fraction in inlet solution and tube diameter on the functioning of the bubble pump is presented and discussed. It was found that, the liquid velocity and pumping ratio increase with increasing heat flux, and then it decreases. Optimal heat flux depends namely on tube diameter variations. Vapour velocity increases linearly with increasing heat flux under designed conditions.

Improving the repeatability of Motor Unit Number Index (MUNIX) by introducing additional epochs at low contraction levels.

Science.gov (United States)

Peng, Yun; Zhang, Yingchun

2017-07-01

To evaluate the repeatability of (Motor Unit Number Index) MUNIX under repeatability conditions, specify the origin of variations and provide strategies for quality control. MUNIX calculations were performed on the bicep brachii muscles of eight healthy subjects. Negative effect of suboptimal electrode positions on MUNIX accuracy was eliminated by employing the high-density surface electromyography technique. MUNIX procedures that utilized a variety of surface interferential pattern (SIP) epoch recruitment strategies (including the original MUNIX procedure, two proposed improvement strategies and their combinations) were described. For each MUNIX procedure, ten thousands of different SIP pools were constructed by randomly recruiting necessary SIP epochs from a large SIP epoch pool (3 datasets, 9 independent electromyography recordings at different contraction levels per dataset and 10 SIP epochs per recording) and implemented for MUNIX calculation. The repeatability of each MUNIX procedure was assessed by summarizing the resulting MUNIX distribution and compared to investigate the effect of SIP epoch selection strategy on repeatability performance. SIP epochs selected at lower contraction levels have a stronger influence on the repeatability of MUNIX than those selected at higher contraction levels. MUNIX under repeatability conditions follows a normal distribution and the standard deviation can be significantly reduced by introducing more epochs near the MUNIX definition line. The MUNIX technique shows an inherent variation attributable to SIP epochs at low contraction levels. It is recommended that more epochs should be sampled at these low contraction levels to improve the repeatability. The present study thoroughly documented the inherent variation of MUNIX and the causes, and offered practical solutions to improve the repeatability of MUNIX. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Conditional Monthly Weather Resampling Procedure for Operational Seasonal Water Resources Forecasting

Science.gov (United States)

Beckers, J.; Weerts, A.; Tijdeman, E.; Welles, E.; McManamon, A.

2013-12-01

To provide reliable and accurate seasonal streamflow forecasts for water resources management several operational hydrologic agencies and hydropower companies around the world use the Extended Streamflow Prediction (ESP) procedure. The ESP in its original implementation does not accommodate for any additional information that the forecaster may have about expected deviations from climatology in the near future. Several attempts have been conducted to improve the skill of the ESP forecast, especially for areas which are affected by teleconnetions (e,g. ENSO, PDO) via selection (Hamlet and Lettenmaier, 1999) or weighting schemes (Werner et al., 2004; Wood and Lettenmaier, 2006; Najafi et al., 2012). A disadvantage of such schemes is that they lead to a reduction of the signal to noise ratio of the probabilistic forecast. To overcome this, we propose a resampling method conditional on climate indices to generate meteorological time series to be used in the ESP. The method can be used to generate a large number of meteorological ensemble members in order to improve the statistical properties of the ensemble. The effectiveness of the method was demonstrated in a real-time operational hydrologic seasonal forecasts system for the Columbia River basin operated by the Bonneville Power Administration. The forecast skill of the k-nn resampler was tested against the original ESP for three basins at the long-range seasonal time scale. The BSS and CRPSS were used to compare the results to those of the original ESP method. Positive forecast skill scores were found for the resampler method conditioned on different indices for the prediction of spring peak flows in the Dworshak and Hungry Horse basin. For the Libby Dam basin however, no improvement of skill was found. The proposed resampling method is a promising practical approach that can add skill to ESP forecasts at the seasonal time scale. Further improvement is possible by fine tuning the method and selecting the most

The effect of test configuration on the true operating conditions of PEM fuel cells. Paper no. IGEC-1-124

International Nuclear Information System (INIS)

Simpson, T.; Li, X.

2005-01-01

The operating conditions of a single PEM fuel cell can be significantly affected by the configuration in which the fuel cell test is setup. This study investigates the effect on the gas dewpoint temperature of not insulating the inlet fittings to a PEM fuel cell and the effect of non-optimal stack control thermocouple placement on fuel cell stack operating temperature. Both of these setup configurations can significantly affect fuel cell membrane humidification conditions, especially in a single fuel cell as demonstrated through the sample test conditions presented in this paper. (author)

Repeat workers' compensation claims: risk factors, costs and work disability

Science.gov (United States)

2011-01-01

Background The objective of our study was to describe factors associated with repeat workers' compensation claims and to compare the work disability arising in workers with single and multiple compensation claims. Methods All initial injury claims lodged by persons of working age during a five year period (1996 to 2000) and any repeat claims were extracted from workers' compensation administrative data in the state of Victoria, Australia. Groups of workers with single and multiple claims were identified. Descriptive analysis of claims by affliction, bodily location, industry segment, occupation, employer and workplace was undertaken. Survival analysis determined the impact of these variables on the time between the claims. The economic impact and duration of work incapacity associated with initial and repeat claims was compared between groups. Results 37% of persons with an initial claim lodged a second claim. This group contained a significantly greater proportion of males, were younger and more likely to be employed in manual occupations and high-risk industries than those with single claims. 78% of repeat claims were for a second injury. Duration between the claims was shortest when the working conditions had not changed. The initial claims of repeat claimants resulted in significantly (p claims. Conclusions A substantial proportion of injured workers experience a second occupational injury or disease. These workers pose a greater economic burden than those with single claims, and also experience a substantially greater cumulative period of work disability. There is potential to reduce the social, health and economic burden of workplace injury by enacting prevention programs targeted at these workers. PMID:21696637

Some simple conditions of bound states of Schroedinger operators in dimension d >= 3

International Nuclear Information System (INIS)

Exner, P.

1984-01-01

A necessary condition for existence of bound states below a given energy of a Schroedinger operator H=-Δ+V on L 2 (Rsup(d)), d>=3, together with a lower bound to the ground-state energy of H are derived using the Sobolev inequalities. It generalizes some recent results to the dimensions d>3 and to the potentials that are not necessarily rapidly decreasing. Comparison to other known necessary conditions is given. The examples of the d-dimensional hydrogen-like atom and the d-dimensional harmonic oscillator are discussed. In both of them the bound to the ground-state energy becomes remarkably tight for large values of d

Opposite patterns of change in perception of imagined and physically induced pain over the course of repeated thermal stimulations.

Science.gov (United States)

Gács, B; Szolcsányi, T; Csathó, Á

2017-08-01

Individuals frequently show habituation to repeated noxious heat. However, given the defensive function of human pain processing, it is reasonable to assume that individuals anticipate that they would become increasingly sensitive to repeated thermal pain stimuli. No previous studies have, however, been addressed to this assumption. Therefore, in the current study, we investigated how healthy human individuals imagine the intensity of repeated thermal pain stimulations, and compared this with the intensity ratings given after physically induced thermal pain trials. Healthy participants (N = 20) gave pain intensity ratings in two conditions: imagined and real thermal pain. In the real pain condition, thermal pain stimuli of two intensities (minimal and moderate pain) were delivered in four consecutive trials. The duration of the peak temperature was 20 s, and stimulation was always delivered to the same location. In each trial, participants rated the pain intensity twice, 5 and 15 s after the onset of the peak temperature. In the imagined pain condition, participants were subjected to a reference pain stimulus and then asked to imagine and rate the same sequence of stimulations as in the induced pain condition. Ratings of imagined pain and physically induced pain followed opposite courses over repeated stimulations: Ratings of imagined pain indicated sensitization, whereas ratings for physically induced pain indicated habituation. The findings were similar for minimal and moderate pain intensities. The findings suggest that, rather than habituating to pain, healthy individuals imagine that they would become increasingly sensitive to repeated thermal pain stimuli. This study identified opposite patterns of change in perception of imagined pain (sensitization) and physically induced pain (habituation). The findings show that individuals anticipate that they would become increasingly sensitive to repeated pain stimuli, which might also have clinical implications. �

Performance analysis of air conditioning system and airflow simulation in an operating theater

Science.gov (United States)

Alhamid, Muhammad Idrus; Budihardjo, Rahmat

2018-02-01

The importance of maintaining performance of a hospital operating theater is to establish an adequate circulation of clean air within the room. The parameter of air distribution in a space should be based on Air Changes per Hour (ACH) to maintain a positive room pressure. The dispersion of airborne particles in the operating theater was governed by regulating the air distribution so that the operating theater meets clean room standards ie ISO 14664 and ASHRAE 170. Here, we introduced several input parameters in a simulation environment to observe the pressure distribution in the room. Input parameters were air temperature, air velocity and volumetric flow rate entering and leaving room for existing and designed condition. In the existing operating theatre, several observations were found. It was found that the outlet air velocity at the HEPA filter above the operating table was too high thus causing a turbulent airflow pattern. Moreover, the setting temperature at 19°C was found to be too low. The supply of air into the room was observed at lower than 20 ACH which is under the standard requirement. Our simulation using FloVent 8.2™ program showed that not only airflow turbulence could be reduced but also the amount of particle contamination could also be minimized.

Does arousal interfere with operant conditioning of spike-wave discharges in genetic epileptic rats?

NARCIS (Netherlands)

Osterhagen, L.; Breteler, M.H.M.; Luijtelaar, E.L.J.M. van

2010-01-01

One of the ways in which brain computer interfaces can be used is neurofeedback (NF). Subjects use their brain activation to control an external device, and with this technique it is also possible to learn to control aspects of the brain activity by operant conditioning. Beneficial effects of NF

Repeated DNA sequences in fungi

Energy Technology Data Exchange (ETDEWEB)

Dutta, S K

1974-11-01

Several fungal species, representatives of all broad groups like basidiomycetes, ascomycetes and phycomycetes, were examined for the nature of repeated DNA sequences by DNA:DNA reassociation studies using hydroxyapatite chromatography. All of the fungal species tested contained 10 to 20 percent repeated DNA sequences. There are approximately 100 to 110 copies of repeated DNA sequences of approximately 4 x 10/sup 7/ daltons piece size of each. Repeated DNA sequence homoduplexes showed on average 5/sup 0/C difference of T/sub e/50 (temperature at which 50 percent duplexes dissociate) values from the corresponding homoduplexes of unfractionated whole DNA. It is suggested that a part of repetitive sequences in fungi constitutes mitochondrial DNA and a part of it constitutes nuclear DNA. (auth)

Vehicle operation characteristic under different ramp entrance conditions in underground road: Analysis, simulation and modelling

Science.gov (United States)

Yao, Qiming; Liu, Shuo; Liu, Yang

2018-05-01

An experimental design was used to study the vehicle operation characteristics of different ramp entrance conditions in underground road. With driving simulator, the experimental scenarios include left or right ramp with first, second and third service level, respectively, to collect vehicle speed, acceleration, lateral displacement and location information at the ramp entrance section. By using paired t-test and ANOVA, the influence factors of vehicle operating characteristics are studied. The result shows that effects of ramp layout and mainline traffic environment on vehicle operation characteristics are significant. The regression model of vehicle traveling distance on acceleration lane is established. Suggestions are made for ramp entrance design of underground road.

Muscle Damage and Metabolic Responses to Repeated-Sprint Running With and Without Deceleration.

Science.gov (United States)

Minahan, Clare L; Poke, Daniel P; Morrison, Jaime; Bellinger, Phillip M

2018-04-04