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Sample records for relative frequency values

  1. Accurate Estimation of Low Fundamental Frequencies from Real-Valued Measurements

    DEFF Research Database (Denmark)

    Christensen, Mads Græsbøll

    2013-01-01

    In this paper, the difficult problem of estimating low fundamental frequencies from real-valued measurements is addressed. The methods commonly employed do not take the phenomena encountered in this scenario into account and thus fail to deliver accurate estimates. The reason for this is that the......In this paper, the difficult problem of estimating low fundamental frequencies from real-valued measurements is addressed. The methods commonly employed do not take the phenomena encountered in this scenario into account and thus fail to deliver accurate estimates. The reason...... for this is that they employ asymptotic approximations that are violated when the harmonics are not well-separated in frequency, something that happens when the observed signal is real-valued and the fundamental frequency is low. To mitigate this, we analyze the problem and present some exact fundamental frequency estimators...

  2. Forecasting Value-at-Risk Using High-Frequency Information

    Directory of Open Access Journals (Sweden)

    Huiyu Huang

    2013-06-01

    Full Text Available in the prediction of quantiles of daily Standard&Poor’s 500 (S&P 500 returns we consider how to use high-frequency 5-minute data. We examine methods that incorporate the high frequency information either indirectly, through combining forecasts (using forecasts generated from returns sampled at different intraday interval, or directly, through combining high frequency information into one model. We consider subsample averaging, bootstrap averaging, forecast averaging methods for the indirect case, and factor models with principal component approach, for both direct and indirect cases. We show that in forecasting the daily S&P 500 index return quantile (Value-at-Risk or VaR is simply the negative of it, using high-frequency information is beneficial, often substantially and particularly so, in forecasting downside risk. Our empirical results show that the averaging methods (subsample averaging, bootstrap averaging, forecast averaging, which serve as different ways of forming the ensemble average from using high-frequency intraday information, provide an excellent forecasting performance compared to using just low-frequency daily information.

  3. Suboptimal Choice in Pigeons: Stimulus Value Predicts Choice over Frequencies.

    Directory of Open Access Journals (Sweden)

    Aaron P Smith

    Full Text Available Pigeons have shown suboptimal gambling-like behavior when preferring a stimulus that infrequently signals reliable reinforcement over alternatives that provide greater reinforcement overall. As a mechanism for this behavior, recent research proposed that the stimulus value of alternatives with more reliable signals for reinforcement will be preferred relatively independently of their frequencies. The present study tested this hypothesis using a simplified design of a Discriminative alternative that, 50% of the time, led to either a signal for 100% reinforcement or a blackout period indicative of 0% reinforcement against a Nondiscriminative alternative that always led to a signal that predicted 50% reinforcement. Pigeons showed a strong preference for the Discriminative alternative that remained despite reducing the frequency of the signal for reinforcement in subsequent phases to 25% and then 12.5%. In Experiment 2, using the original design of Experiment 1, the stimulus following choice of the Nondiscriminative alternative was increased to 75% and then to 100%. Results showed that preference for the Discriminative alternative decreased only when the signals for reinforcement for the two alternatives predicted the same probability of reinforcement. The ability of several models to predict this behavior are discussed, but the terminal link stimulus value offers the most parsimonious account of this suboptimal behavior.

  4. Electromagnetic wave attenuation in the superconducting waveguides at frequencies above the critical value

    International Nuclear Information System (INIS)

    Gashimov, A.M.; Gumbatov, S.G.

    2004-01-01

    The behavior of attenuation factor α(ν) in a wide relative frequency rAe 1 c ) at microwave energy transmission by the round superconducting waveguides is investigated. It is revealed that, despite of increasing of surface resistance with increasing ν, α(ν) sharply decreases in the rAe 1 min at ν→∞. Such behavior α(ν) is due to joint appearance of opposite influences of wave frequency and surface resistance of the superconducting material. The waveguide with radius r=1 m, made of high-temperature superconductor, has the highest value of efficiency (98% at ν=4)

  5. The Value Estimation of an HFGW Frequency Time Standard for Telecommunications Network Optimization

    Science.gov (United States)

    Harper, Colby; Stephenson, Gary

    2007-01-01

    The emerging technology of gravitational wave control is used to augment a communication system using a development roadmap suggested in Stephenson (2003) for applications emphasized in Baker (2005). In the present paper consideration is given to the value of a High Frequency Gravitational Wave (HFGW) channel purely as providing a method of frequency and time reference distribution for use within conventional Radio Frequency (RF) telecommunications networks. Specifically, the native value of conventional telecommunications networks may be optimized by using an unperturbed frequency time standard (FTS) to (1) improve terminal navigation and Doppler estimation performance via improved time difference of arrival (TDOA) from a universal time reference, and (2) improve acquisition speed, coding efficiency, and dynamic bandwidth efficiency through the use of a universal frequency reference. A model utilizing a discounted cash flow technique provides an estimation of the additional value using HFGW FTS technology could bring to a mixed technology HFGW/RF network. By applying a simple net present value analysis with supporting reference valuations to such a network, it is demonstrated that an HFGW FTS could create a sizable improvement within an otherwise conventional RF telecommunications network. Our conservative model establishes a low-side value estimate of approximately 50B USD Net Present Value for an HFGW FTS service, with reasonable potential high-side values to significant multiples of this low-side value floor.

  6. Coupling coefficient between the Pc3 frequency and the value of the interplanetary magnetic field

    International Nuclear Information System (INIS)

    Gul'el'mi, A.V.

    1988-01-01

    Mean value and spread of coupling coefficient g between geomagnetic pulsation Ps3 frequency and interplanetary magnetic field (IMF) value are evaluated according to a set of all measurements described in literature and to additional measurements at Borok observatory (50 hour intervals in January, 1973). Attention is paid to a relatively small spread of g and to a weak g dependence on IMF orientation. The both facts are out of scope of the elementary Ps3 theory

  7. Frequency and Efficacy of Talk-Related Tasks in Primary Science

    Science.gov (United States)

    Braund, Martin; Leigh, Joanne

    2013-04-01

    Pupil talk and discussion are seen as having important social and cognitive outcomes. In science classes, pupils' collaborative talk supports the construction of meaning and helps examine the status of evidence, theory and knowledge. However, pupil interactive talk in groups is rare in science lessons. The research reported is part of a project to increase the amount of pupil-pupil talk in primary schools through a programme of teaching and professional development. Pupils' self-reports of the frequency and learning efficacies of talk related activities in science lessons were collected before and after a programme of teaching in 24 schools in one of the most socially and educationally deprived areas of England. Findings showed pupils valued talking about their ideas over listening to those of other pupils. Science talk frequency (STF) was closely correlated with science talk efficacy (STE) and both were positively correlated with pupils' attitudes to school science. Analysis of covariance (ANCOVA) of the correlation of STF with STE showed values were independent of gender and ability but that school experience was a significant factor. After the teaching programme and, contrary to expectations, the frequency of talk activities in science lessons appeared to have decreased but varied according to class grades. The degree of correlation between STF and STE was stronger after the teaching in over half of the schools. Schools where STF/STE strengthened most as a result of teaching were those involved in an additional initiative to use modelled talk related to industrial contexts.

  8. Frequency-Weighted Balancing Related Controller Reduction

    OpenAIRE

    Varga, Andras; Anderson, Brian D.O.

    2002-01-01

    The efficient solution of a class of controller approximation problems by using frequency-weighted balancing related model reduction approaches is considered. It is shown that for certain standard performance and stability enforcing frequency-weights, the computation of the frequency-weighted controllability and observability grammians can be done by solving reduced order Lyapunov equations regardless the controller itself is stable or unstable. The new approach can be used in conjunction wit...

  9. Frequency of low-value care in Alberta, Canada: a retrospective cohort study.

    Science.gov (United States)

    McAlister, Finlay A; Lin, Meng; Bakal, Jeff; Dean, Stafford

    2018-05-01

    To determine how frequently 10 low-value services highlighted by Choosing Wisely are done and what factors influence their provision. This is a retrospective cohort study using routinely collected health data from five linked data sets from 2012 to 2015 in the Canadian province of Alberta to determine the frequency with which 10 low-value services were provided. Between 2012 and 2015, 162 143 people (4% of all 3 814 536 adult Albertans and 5% of the 3  423 135 who saw a physician at least once in that time frame) received at least one of the 10 low-value services, including 29.8% of Albertans older than 75 years (57 811 of 194 068). The proportion of adults receiving low-value services ranged from carotid artery imaging in 0.1% of asymptomatic adults without cerebrovascular disease, to prostate-specific antigen (PSA) testing in 55.5% of men 75 years or older without a history of prostate cancer. Although age, Charlson scores and frequency of primary care visits were associated with low-value service provision, the directions of the association differed across services; however, higher socioeconomic status, increased frequency of specialist contact and higher ratio of specialists to primary care physicians in the patient's region were associated with an increased risk of receiving all of the low-value services we examined. The low-value services which resulted in the greatest costs to the healthcare system were cervical cancer screening in women older than 65 without history of cervical dysplasia or genital cancer, PSA testing in men older than 75 without history of prostate cancer and preoperative stress testing/cardiac imaging before non-cardiac surgery. Even within a universal coverage healthcare system, the proportion of patients receiving low-value services varied widely (from <0.1% to 56%). Increased use was associated with higher socioeconomic status, increased frequency of specialist contact and higher ratio of specialists to primary care

  10. Frequency of Candidiasis and Colonization of Candida albicans in Relation to Oral Contraceptive Pills.

    Science.gov (United States)

    Aminzadeh, Atousa; Sabeti Sanat, Ali; Nik Akhtar, Saeed

    2016-10-01

    Candidiasis, the infection caused by Candida albicans , is one of the most common infections of the oral cavity in humans. Candidiasis causes irritation and is known for its carcinogenic effects. Thus, it is important to recognize the predisposing factors for this opportunistic infection. Several previous studies have demonstrated an increased frequency of vaginal candidiasis in relation to oral contraceptive consumption. Only a few studies on the relation between oral contraceptives and oral candidiasis have been previously conducted. This study aims to evaluate the possible relation between oral contraceptive pills and oral candidiasis. This analytic, case-control study included 40 non-pregnant women divided into two groups: 20 who used oral contraceptive pills and 20 who did not. The groups were matched according to age, oral health, and past and present medical history. Samples were collected from the tongue's dorsum using a cotton swab and inoculated on CHROMagar culture plates. The frequency of positive cultures and the number of Candida colonies were compared between the two groups using independent t-tests and Mann-Whitney statistical tests with SPSS18 software. The frequency of positive cultures of Candida albicans was higher (P value = 0.03) for the case group. Also, the number of C. albicans and C. krusei was significantly higher for the case group compared to the control group (P value = 0.04, P value = 0.03). The results of the present study demonstrate that oral contraceptives containing estradiol can lead to Candida colonization in the oral cavity. It is recommended that further studies comparing the influence of oral contraceptives on Candida's adherence to the epithelium is highly recommended.

  11. Reliability of mechanisms with periodic random modal frequencies using an extreme value-based approach

    International Nuclear Information System (INIS)

    Savage, Gordon J.; Zhang, Xufang; Son, Young Kap; Pandey, Mahesh D.

    2016-01-01

    Resonance in a dynamic system is to be avoided since it often leads to impaired performance, overstressing, fatigue fracture and adverse human reactions. Thus, it is necessary to know the modal frequencies and ensure they do not coincide with any applied periodic loadings. For a rotating planar mechanism, the coefficients in the mass and stiffness matrices are periodically varying, and if the underlying geometry and material properties are treated as random variables then the modal frequencies are both position-dependent and probabilistic. The avoidance of resonance is now a complex problem. Herein, free vibration analysis helps determine ranges of modal frequencies that in turn, identify the running speeds of the mechanism to be avoided. This paper presents an efficient and accurate sample-based approach to determine probabilistic minimum and maximum extremes of the fundamental frequencies and the angular positions of their occurrence. Then, given critical lower and upper frequency constraints it is straightforward to determine reliability in terms of probability of exceedance. The novelty of the proposed approach is that the original expensive and implicit mechanistic model is replaced by an explicit meta-model that captures the tolerances of the design variables over the entire range of angular positions: position-dependent eigenvalues can be found easily and quickly. Extreme-value statistics of the modal frequencies and extreme-value statistics of the angular positions are readily computed through MCS. Limit-state surfaces that connect the frequencies to the design variables may be easily constructed. Error analysis identifies three errors and the paper presents ways to control them so the methodology can be sufficiently accurate. A numerical example of a flexible four-bar linkage shows the proposed methodology has engineering applications. The impact of the proposed methodology is two-fold: it presents a safe-side analysis based on free vibration methods to

  12. Frequency and Magnitude Analysis of the Macro-instability Related Component of the Tangential Force Affecting Radial Baffles in a Stirred Vessel

    Directory of Open Access Journals (Sweden)

    P. Hasal

    2002-01-01

    Full Text Available Experimental data obtained by measuring the tangential component of force affecting radial baffles in a flat-bottomed cylindrical mixing vessel stirred with pitched blade impellers is analysed. The maximum mean tangential force is detected at the vessel bottom. The mean force value increases somewhat with decreasing impeller off-bottom clearance and is noticeably affected by the number of impeller blades. Spectral analysis of the experimental data clearly demonstrated the presence of its macro-instability (MI related low-frequency component embedded in the total force at all values of impeller Reynolds number. The dimensionless frequency of the occurrence of the MI force component is independent of stirring speed, position along the baffle, number of impeller blades and liquid viscosity. Its mean value is about 0.074. The relative magnitude (QMI of the MI-related component of the total force is evaluated by a combination of proper orthogonal decomposition (POD and spectral analysis. Relative magnitude QMI was analysed in dependence on the frequency of the impeller revolution, the axial position of the measuring point in the vessel, the number of impeller blades, the impeller off-bottom clearance, and liquid viscosity. Higher values of QMI are observed at higher impeller off-bottom clearance height and (generally QMI decreases slightly with increasing impeller speed. The QMI value decreases in the direction from vessel bottom to liquid level. No evident difference was observed between 4 blade and 6 blade impellers. Liquid viscosity has only a marginal impact on the QMI value.

  13. [The value of spectral frequency analysis by Doppler examination (author's transl)].

    Science.gov (United States)

    Boccalon, H; Reggi, M; Lozes, A; Canal, C; Jausseran, J M; Courbier, R; Puel, P; Enjalbert, A

    1981-01-01

    Arterial stenoses of moderate extent may involve modifications of the blood flow. Arterial shading is not always examined at the best incident angle to assess the extent of the stenosis. Spectral frequency analysis by Doppler examination is a good means of evaluating the effect of moderate arterial lesions. The present study was carried out with a Doppler effect having an acoustic spectrum, which is shown in a histogram having 16 frequency bands. The values were recorded on the two femoral arteries. A study was also made of 49 normal subjects so as to establish a normal envelope histogram, taking into account the following parameters: maximum peak (800 Hz), low cut-off frequency (420 Hz), high cut-off frequency (2,600 Hz); the first peak was found to be present in 81 % of the subjects (at 375 Hz) and the second peak in 75 % of the subjects (2,020 Hz). Thirteen patients with iliac lesions of different extent were included in the study; details of these lesions were established in all cases by aortography. None of the recorded frequency histograms were located within the normal envelope. Two cases of moderate iliac stenoses were noted ( Less Than 50 % of the diameter) which interfered with the histogram, even though the femoral velocity signal was normal.

  14. Band Width of Acoustic Resonance Frequency Relatively Natural Frequency of Fuel Rod Vibration

    Energy Technology Data Exchange (ETDEWEB)

    Proskuryakov, Konstantin Nicolaevich; Moukhine, V.S.; Novikov, K.S.; Galivets, E.Yu. [MPEI - TU, 14, Krasnokazarmennaya str., Moscow, 111250 (Russian Federation)

    2009-06-15

    In flow induced vibrations the fluid flow is the energy source that causes vibration. Acoustic resonance in piping may lead to severe problems due to over-stressing of components or significant losses of efficiency. Steady oscillatory flow in NPP primary loop can be induced by the pulsating flow introduced by reactor circulating pump or may be set up by self-excitation. Dynamic forces generated by the turbulent flow of coolant in reactor cores cause fuel rods (FR) and fuel assembly (FA) to vibrate. Flow-induced FR and FA vibrations can generally be broken into three groups: large amplitude 'resonance type' vibrations, which can cause immediate rod failure or severe damage to the rod and its support structure, middle amplitude 'within bandwidth of resonance frequency type' vibrations responsible for more gradual wear and fatigue at the contact surface between the fuel cladding and rod support and small amplitude vibrations, 'out of bandwidth of resonance frequency type' responsible for permissible wear and fatigue at the contact surface between the fuel cladding and rod support. Ultimately, these vibration types can result in a cladding breach, and therefore must be accounted for in the thermal hydraulic design of FR and FA and reactor internals. In paper the technique of definition of quality factor (Q) of acoustic contour of the coolant is presented. The value of Q defines a range of frequencies of acoustic fluctuations of the coolant within which the resonance of oscillations of the structure and the coolant is realized. Method of evaluation of so called band width (BW) of acoustic resonance frequency is worked out and presented in the paper. BW characterises the range of the frequency of coolant pressure oscillations within which the frequency of coolant pressure oscillations matches the fuel assembly's natural frequency of vibration (its resonance frequency). Paper show the way of detuning acoustic resonance from natural

  15. An approach toward incorporation of global warming effects into Intensity-Duration-Frequency values

    Science.gov (United States)

    Kunkel, K.; Easterling, D. R.

    2017-12-01

    Rising global temperatures from increasing greenhouse gas concentrations will increase overall atmospheric water vapor concentrations. There is a high level of scientific confidence that this will increase the future intensity and frequency of extreme precipitation events, even in regions where overall precipitation may decrease. For control of runoff from extreme rainfall, infrastructure engineering utilizes design values of rainfall known as Intensity-Duration-Frequency (IDF) values. Use of the existing IDF values, which are based solely on historical climate records, is likely to lead to under-design of runoff control structures, and associated increased flood damages. However, future changes in IDF values are uncertain and probably regionally variable. Our paradigm is that changes in IDF values will result from changes in atmospheric capacity (water vapor concentrations) and opportunity (the number and intensity of heavy precipitation-producing storm systems). Relevant storm systems being investigated include extratropical cyclones and their associated fronts, tropical cyclones, and the North American Monsoon system. The overall approach involves developing IDF adjustment factors for changes in these components of the climate system. The adjustment factors have associated uncertainties, primarily from (1) uncertainties in the future pathway of greenhouse gas emissions and (2) variations among climate models in the sensitivity of the climate system to greenhouse gas concentration changes. In addition to meteorological considerations, the lifetime of projects designed using IDF values is an essential consideration because the IDF values may change substantially during that time. The initial results of this project will be discussed.

  16. Effect of echolocation behavior-related constant frequency-frequency modulation sound on the frequency tuning of inferior collicular neurons in Hipposideros armiger.

    Science.gov (United States)

    Tang, Jia; Fu, Zi-Ying; Wei, Chen-Xue; Chen, Qi-Cai

    2015-08-01

    In constant frequency-frequency modulation (CF-FM) bats, the CF-FM echolocation signals include both CF and FM components, yet the role of such complex acoustic signals in frequency resolution by bats remains unknown. Using CF and CF-FM echolocation signals as acoustic stimuli, the responses of inferior collicular (IC) neurons of Hipposideros armiger were obtained by extracellular recordings. We tested the effect of preceding CF or CF-FM sounds on the shape of the frequency tuning curves (FTCs) of IC neurons. Results showed that both CF-FM and CF sounds reduced the number of FTCs with tailed lower-frequency-side of IC neurons. However, more IC neurons experienced such conversion after adding CF-FM sound compared with CF sound. We also found that the Q 20 value of the FTC of IC neurons experienced the largest increase with the addition of CF-FM sound. Moreover, only CF-FM sound could cause an increase in the slope of the neurons' FTCs, and such increase occurred mainly in the lower-frequency edge. These results suggested that CF-FM sound could increase the accuracy of frequency analysis of echo and cut-off low-frequency elements from the habitat of bats more than CF sound.

  17. On one-parametric formula relating the frequencies of twin-peak quasi-periodic oscillations

    Science.gov (United States)

    Török, Gabriel; Goluchová, Kateřina; Šrámková, Eva; Horák, Jiří; Bakala, Pavel; Urbanec, Martin

    2018-01-01

    Twin-peak quasi-periodic oscillations (QPOs) are observed in several low-mass X-ray binary systems containing neutron stars. Timing the analysis of X-ray fluxes of more than dozen of such systems reveals remarkable correlations between the frequencies of two characteristic peaks present in the power density spectra. The individual correlations clearly differ, but they roughly follow a common individual pattern. High values of measured QPO frequencies and strong modulation of the X-ray flux both suggest that the observed correlations are connected to orbital motion in the innermost part of an accretion disc. Several attempts to model these correlations with simple geodesic orbital models or phenomenological relations have failed in the past. We find and explore a surprisingly simple analytic relation that reproduces individual correlations for a group of several sources through a single parameter. When an additional free parameter is considered within our relation, it well reproduces the data of a large group of 14 sources. The very existence and form of this simple relation support the hypothesis of the orbital origin of QPOs and provide the key for further development of QPO models. We discuss a possible physical interpretation of our relation's parameters and their links to concrete QPO models.

  18. A two-component generalized extreme value distribution for precipitation frequency analysis

    Czech Academy of Sciences Publication Activity Database

    Rulfová, Zuzana; Buishand, A.; Roth, M.; Kyselý, Jan

    2016-01-01

    Roč. 534, March (2016), s. 659-668 ISSN 0022-1694 R&D Projects: GA ČR(CZ) GA14-18675S Institutional support: RVO:68378289 Keywords : precipitation extremes * two-component extreme value distribution * regional frequency analysis * convective precipitation * stratiform precipitation * Central Europe Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 3.483, year: 2016 http://www.sciencedirect.com/science/article/pii/S0022169416000500

  19. Relational Resources in Value Adding Webs

    DEFF Research Database (Denmark)

    Gretzinger, Susanne; Royer, Susanne

    2014-01-01

    The fact that the main source of value creation is rooted within networks raises the question of the impact of social capital on relational rents. The main objectives of this paper therefore are to investigate how value creation on the relational level of a cluster can be systematised to come to ...... the high value of informal cluster structures. The paper develops implications for the cluster firms as well as the cluster management in its role as a broker and a moderator....

  20. Doppler frequency in interplanetary radar and general relativity

    Science.gov (United States)

    Mcvittie, G. C.

    1972-01-01

    The change of frequency of an interplanetary radar signal sent from the earth to another planet or to a space probe is worked out according to general relativity. The Schwarzschild spacetime is employed and its null geodesics control the motion of the signals. Exact Doppler frequency formulas are derived for one-way and two-way radar in terms of an arbitrary Schwarzschild radial coordinate. A reduction to the special relativity case is used to interpret the formulas in terms of the relative radial velocity of emitter and target. The general relativity corrections are worked out approximately for each of three possible Schwarzschild radial coordinates, and a numerical example is given. The amount of the correction is different according as one or the other of the Schwarzschild coordinates is identified with the radius vector deduced from classical celestial mechanics. The identification problem is discussed.

  1. Experimental and Numerical Investigation of Thermoacoustic Sources Related to High-Frequency Instabilities

    Directory of Open Access Journals (Sweden)

    Mathieu Zellhuber

    2014-03-01

    Full Text Available Flame dynamics related to high-frequency instabilities in gas turbine combustors are investigated using experimental observations and numerical simulations. Two different combustor types are studied, a premix swirl combustor (experiment and a generic reheat combustor (simulation. In both cases, a very similar dynamic behaviour of the reaction zone is observed, with the appearance of transverse displacement and coherent flame wrinkling. From these observations, a model for the thermoacoustic feedback linked to transverse modes is proposed. The model splits heat release rate fluctuations into distinct contributions that are related to flame displacement and variations of the mass burning rate. The decomposition procedure is applied on the numerical data and successfully verified by comparing a reconstructed Rayleigh index with the directly computed value. It thus allows to quantify the relative importance of various feedback mechanisms for a given setup.

  2. Frequency of hyponatraemia and its influence on liver cirrhosis-related complications

    International Nuclear Information System (INIS)

    Sheikh, S.; Khalid, S.; Baloch, G.H.

    2010-01-01

    To evaluate the frequency, clinical associations and prognostic impact of hyponatraemia on cirrhosis related complications in patients with cirrhosis of liver. In this case control study 217 cirrhotic patients consecutively admitted to our department from September 2006 to November 2007 were studied. Serum sodium levels were determined in all patients admitted. The cutoff level of 130 meq/l was chosen because it is widely accepted to define hyponatraemia in patients with cirrhosis while the level of 135 meq/L is the lower normal value. Patients were grouped on the basis of serum sodium concentration into serum sodium 135 meq /l (Group 3). P values of less than 0.05 were considered as significant. The patients with hyponatraemia Group( 135 meq/l) for the severity of liver disease, degree of ascites and other cirrhosis related complications such as hepatorenal syndrome, spontaneous bacterial peritonitis and hepatic encephalopathy. This case control study constituted 217 consecutive cirrhotic patients of which 141(65%) were male and 76/217 (35%) were female. Hyponatraemia (sodium 135. Out of 58 patients with hyponatraemia, 48 were in child - Pugh C class (p=0.001). Patients with serum sodium 135 meq/l). Hyponatraemia is frequent in cirrhotic patients. It is seldom spontaneous and has a negative influence on cirrhosis related complications (JPMA 60:116; 2010). (author)

  3. System Frequency as Information Carrier in AC Power Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Heussen, Kai; You, Shi

    2015-01-01

    Power generators contain control systems able to regulate system frequency, but the frequency setpoint values are only rarely modified from nominal values. This paper describes design considerations for a communication system from generators to frequency sensitive distributed energy resourc es (FS......-DER) using changes to frequency setpoint values of genera- tors. Signaling discrete system states by generating off-nominal system frequency values can be used as a novel narrowband unidirectional broadcast communications channel. This paper describes two protocols for utilizing off-nominal frequencies...... to carry information: First, a protocol for dispatching blocks of FS- DER that is suitable for systems restricted to relatively slow rates of change of frequency (ROCOF). Second, for systems that allow higher ROCOF values, the feasibility of using power generation resources as a power line communication...

  4. The CIPM list of recommended frequency standard values: guidelines and procedures

    Science.gov (United States)

    Riehle, Fritz; Gill, Patrick; Arias, Felicitas; Robertsson, Lennart

    2018-04-01

    A list of standard reference frequency values (LoF) of quantum transitions from the microwave to the optical regime has been recommended by the International Committee for Weights and Measures (Comité international des poids et mesures, CIPM) for use in basic research, technology, and for the metrology of time, frequency and length. The CIPM LoF contains entries that are recommended as secondary representations of the second in the International System of Units, and entries that can be used to serve as realizations of the definition of the metre. The historical perspective that led to the CIPM LoF is outlined. Procedures have been developed for updating existing, and validating new, entries into the CIPM LoF. The CIPM LoF might serve as an entry for a future redefinition of the second by an optical transition.

  5. [Study the impacts of diagnosis on occupational noise-induced deafness after bring into the different high frequency hearing threshold weighted value].

    Science.gov (United States)

    Xue, L J; Yang, A C; Chen, H; Huang, W X; Guo, J J; Liang, X Y; Chen, Z Q; Zheng, Q L

    2017-11-20

    Objective: Study of the results and the degree on occupational noise-induced deafness in-to the different high frequency hearing threshold weighted value, in order to provide theoretical basis for the re-vision of diagnostic criteria on occupational noise-induced deafness. Methods: A retrospective study was con-ducted to investigate the cases on the diagnosis of occupational noise-induced deafness in Guangdong province hospital for occupational disease prevention and treatment from January 2016 to January 2017. Based on the re-sults of the 3 hearing test for each test interval greater than 3 days in the hospital, the best threshold of each frequency was obtained, and based on the diagnostic criteria of occupational noise deafness in 2007 edition, Chi square test, t test and variance analysis were used to measure SPSS21.0 data, their differences are tested among the means of speech frequency and the high frequency weighted value into different age group, noise ex-posure group, and diagnostic classification between different dimensions. Results: 1. There were totally 168 cases in accordance with the study plan, male 154 cases, female 14 cases, the average age was 41.18 ±6.07 years old. 2. The diagnosis rate was increased into the weighted value of different high frequency than the mean value of pure speech frequency, the weighted 4 kHz frequency increased by 13.69% (χ(2)=9.880, P =0.002) , 6 kHz increased by 15.47% (χ(2)=9.985, P =0.002) and 4 kHz+6 kHz increased by15.47% (χ(2)=9.985, P =0.002) , the difference was statistically significant. The diagnostic rate of different high threshold had no obvious differ-ence between the genders. 3. The age groups were divided into less than or equal to 40years old group (A group) and 40-50 years old group (group B) , there were higher the diagnostic rate between high frequency weighted 4 kHz (A group χ(2)=3.380, P =0.050; B group χ(2)=4.054, P =0.032) , weighted 6 kHz (A group χ(2)=6.362, P =0.012; B group χ(2

  6. On the low frequency characteristics of head-related transfer function

    Institute of Scientific and Technical Information of China (English)

    XIE Bosun

    2009-01-01

    A method to correct the measured head-related transfer functions (HRTFs) at low frequency was proposed. By analyzing the HRTFs from the spherical head model at low frequency, it is proved that below the frequency of 400 Hz, magnitude of HRTF is nearly constant and the phase is a linear function of frequency both for the far and near field. Therefore, if the HRTFs above 400 Hz are accurately measured by experiment, it is able to correct the HRTFs at low frequency by the theoretical model. The results of calculation and subjective experiment show that the feasibility of the proposed method.

  7. Testing relationships between values and food-related lifestyle:

    DEFF Research Database (Denmark)

    Brunsø, Karen; Scholderer, Joachim; Grunert, Klaus G.

    2004-01-01

    The value survey developed by Shalom Schwartz (1992) has been applied in many countries with different purposes. In this study we present a new way of analysing the theoretically assumed circumplex structure of Schwartz value survey and its relationships to other constructs, here the instrument...... food-related lifestyle. In two countries; Germany and Spain, data were collected. In each country 1000 interviews were carried out where consumers were asked about their value priorities and about their food-related lifestyle. The study provides new insights into the way values influence peoples' food......-related lifestyle in Germany and Spain, and the results validate both the Schwartz value survey and the food-related lifestyle instrument in a nomological sense, since significant and meaningful relationships were found between the two constructs....

  8. Feedback-Based Eco-Design for Integrating the Recency, Frequency, and Monetary Value of Eco-Efficiency into Sustainability Management

    Directory of Open Access Journals (Sweden)

    Rui Yang Chen

    2016-09-01

    Full Text Available Customer feedback is used to understand customer requirements. Early design phases require the consideration of items including manufacturing, the environment, and sustainability management. Therefore, it is crucial that eco-efficiency is taken into account in the early design phases. Traditionally, eco-efficiency is considered only in terms of eco-design issues, not customer requirements based on business values such as Recency, Frequency, and Monetary (RFM value. In the meantime, integrating innovation from eco-design is one important aspect. Here, I propose that customer feedback-based eco-efficiency and TRIZ-based innovation can be considered in early eco-design based on the RFM value for sustainability management. The analytic hierarchy process (AHP and fuzzy-based AHP were integrated to explore the relative weights of RFM variables for business value evaluation. The innovative method of the paper is using a TRIZ contradiction matrix associated with engineering parameters for eco-design. The experimental study has been carried out, and it meets the forecasting business value for green product usage. The business value was used as the decision-making factor in order to evaluate both environmental and marketing performance.

  9. Absolute frequency list of the ν3-band transitions of methane at a relative uncertainty level of 10(-11).

    Science.gov (United States)

    Okubo, Sho; Nakayama, Hirotaka; Iwakuni, Kana; Inaba, Hajime; Sasada, Hiroyuki

    2011-11-21

    We determine the absolute frequencies of 56 rotation-vibration transitions of the ν(3) band of CH(4) from 88.2 to 90.5 THz with a typical uncertainty of 2 kHz corresponding to a relative uncertainty of 2.2 × 10(-11) over an average time of a few hundred seconds. Saturated absorption lines are observed using a difference-frequency-generation source and a cavity-enhanced absorption cell, and the transition frequencies are measured with a fiber-laser-based optical frequency comb referenced to a rubidium atomic clock linked to the international atomic time. The determined value of the P(7) F(2)((2)) line is consistent with the International Committee for Weights and Measures recommendation within the uncertainty. © 2011 Optical Society of America

  10. Frequency and predictive values of first rank symptoms at baseline among 362 young adult patients with first-episode schizophrenia Results from the Danish OPUS study

    DEFF Research Database (Denmark)

    Thorup, Anne; Petersen, Lone; Jeppesen, Pia

    2007-01-01

    To investigate the frequency of the Schneiderian First Rank Symptoms (FRSs) in a representative group of patients with first-episode schizophrenia and to analyse the predictive value of these symptoms in relation to psychopathology, work situation, depression, dependency and admission after 2 years...

  11. Are personal values related to sustainable attribute choice

    OpenAIRE

    Mueller, Simone; Sirieix, Lucie; Remaud, Hervé

    2011-01-01

    Purpose: A cross-cultural study with large representative samples analyses to what degree Schwartz’s personal values and environmental concerns are related to consumers’ choices of wine with sustainable characteristics. Methodology: Across seven countries, the attribute importance and willingness to pay of consumer segments resulting from choice experiments are related to Schwartz’s personal value dimensions and environmental attitudes. Findings: Personal values were only weakly related to re...

  12. Relational values resonate broadly and differently than intrinsic or instrumental values, or the New Ecological Paradigm.

    Science.gov (United States)

    Klain, Sarah C; Olmsted, Paige; Chan, Kai M A; Satterfield, Terre

    2017-01-01

    Value orientations used to explain or justify conservation have been rooted in arguments about how much and in what context to emphasize the intrinsic versus instrumental value of nature. Equally prominent are characterizations of beliefs known as the New Ecological Paradigm (NEP), often used to help explain pro-environmental behaviour. A recent alternative to these positions has been identified as 'relational value'-broadly, values linking people and ecosystems via tangible and intangible relationships to nature as well as the principles, virtues and notions of a good life that may accompany these. This paper examines whether relational values are distinct from other value orientation and have potential to alleviate the intrinsic-instrumental debate. To test this possibility, we sought to operationalize the construct-relational values-by developing six relational statements. We ask: 1) Do the individual statements used to characterize relational values demonstrate internal coherence as either a single or multi-dimensional construct? 2) Do relational value statements (including those strongly stated) resonate with diverse populations? 3) Do people respond to relational value statements in a consistently different way than NEP scale statements? Data for this work is drawn from an online panel of residents of northeastern US (n = 400), as well as a sample of Costa Rican farmers (n = 253) and tourists in Costa Rica (n = 260). Results indicate relational values are distinct as a construct when compared to the NEP.

  13. Core Values: A History of Values-Related Initiatives in the Air Force

    National Research Council Canada - National Science Library

    Dierker, Gregory

    1997-01-01

    .... This study specifically examines two of the assumptions made in the current Air Force Core Values initiative against the historic values-related initiatives to identify any differences that have occurred over time...

  14. The value prescription: relative value theorem as a call to action.

    Science.gov (United States)

    Alston, Greg L; Blizzard, Joseph C

    2012-01-01

    The Joint Commission of Pharmacy Practitioners Future Vision of Pharmacy Practice 2015 (2005) and Project Destiny (2008) clearly defined a vision for transforming community practice pharmacy from a culture of dispensing drugs to the provision of services. Several viable service offerings were identified. Pharmacy has not yet fully capitalized on these opportunities. Pharmacy must demonstrate value in providing these services to remain viable in the marketplace. Many pharmacists do not understand how value is created and lack sufficient marketing skills to position their practice for long-term success. The relative value theorem (RVT) describes in simple terms the key elements that drive purchase decisions and thus marketing decisions: (P+S)×PV=RV (P, price; S, service; PV, perceived value; RV, relative value). A consumer compares the P, extra S, and PV of the purchase against all potential uses of their scarce resources before deciding what to buy. Evidence suggests that understanding and applying the principles of RVT is a critical skill for pharmacy professionals in all practice settings to master if they plan to remain viable players in the health care marketplace of the future. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. In vitro evaluation of resonance frequency analysis values to different implant contact ratio and stiffness of surrounding material.

    Science.gov (United States)

    Kwak, Mu-Seung; Kim, Seok-Gyu

    2013-11-01

    The present study was aimed to evaluate the influence of implant contact ratio and stiffness of implant-surrounding materials on the resonance frequency analysis (RFA) values. Seventy resin blocks that had the different amounts (100, 50, 30, 15%) of resin-implant contact (RIC) were fabricated. Ten silicone putty blocks with 100% silicone-implant contact were also made. The implants with Ø5.0 mm × 13.0 mm were placed on eighty specimen blocks. The RFA value was measured on the transducer that was connected to each implant by Osstell Mentor. Kruskal-Wallis and Scheffe's tests (α=.05) were done for statistical analysis. The control resin group with 100% RIC had the highest RFA value of 83.9, which was significantly different only from the resin group with 15% RIC among the resin groups. The silicone putty group with 100% contact had the lowest RFA value of 36.6 and showed statistically significant differences from the resin groups. Within the limitations of this in vitro study, there was no significant difference in the RFA values among the resin groups with different RIC's except when the RIC difference was more than 85%. A significant increase in the RFA value was observed related to the increase in stiffness of material around implant.

  16. Aesthetic appreciation: event-related field and time-frequency analyses.

    Science.gov (United States)

    Munar, Enric; Nadal, Marcos; Castellanos, Nazareth P; Flexas, Albert; Maestú, Fernando; Mirasso, Claudio; Cela-Conde, Camilo J

    2011-01-01

    Improvements in neuroimaging methods have afforded significant advances in our knowledge of the cognitive and neural foundations of aesthetic appreciation. We used magnetoencephalography (MEG) to register brain activity while participants decided about the beauty of visual stimuli. The data were analyzed with event-related field (ERF) and Time-Frequency (TF) procedures. ERFs revealed no significant differences between brain activity related with stimuli rated as "beautiful" and "not beautiful." TF analysis showed clear differences between both conditions 400 ms after stimulus onset. Oscillatory power was greater for stimuli rated as "beautiful" than those regarded as "not beautiful" in the four frequency bands (theta, alpha, beta, and gamma). These results are interpreted in the frame of synchronization studies.

  17. Illness related wage and productivity losses: Valuing 'presenteeism'.

    Science.gov (United States)

    Zhang, Wei; Sun, Huiying; Woodcock, Simon; Anis, Aslam

    2015-12-01

    One source of productivity loss due to illness is the reduced "quantity" or "quality" of labor input while working, often referred to as presenteeism. Illness-related presenteeism has been found to be potentially more costly than absenteeism. To value presenteeism, existing methods use wages as a proxy for marginal productivity at the firm level. However, wage may not equal marginal productivity in some scenarios. One instance is when a job involves team production and perfect substitutes for workers are not readily available. Using a Canadian linked employer-employee survey (2001-2005), we test whether relative wage equals relative marginal productivity among team workers and non-team workers with different frequencies of presenteeism (reduction at work due to illness). For the pooled cross-sectional estimates (2001, 2003, 2005) we obtain 13,755 observations with 6842 unique workplaces. There are 6490 observations for the first differences estimates from the odd years and 5263 observations for the first differences estimates from 2001 to 2002 and 2003 to 2004. We find that in both small and large firms, team workers with frequent reductions at work are less productive but earn similarly compared with non-team workers without reductions. We also find that in small firms, workers with occasional work reductions are more productive than workers without reductions, but the reverse is true in large firms. The study findings partially support the literature stating that productivity loss resulting from employee presenteeism could exceed wages if team work is involved. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. The relative frequency of common neuromuscular diagnoses in a reference center

    OpenAIRE

    Cotta, Ana; Paim, Júlia Filardi; Carvalho, Elmano; da-Cunha-Júnior, Antonio Lopes; Navarro, Monica M.; Valicek, Jaquelin; Menezes, Miriam Melo; Nunes, Simone Vilela; Xavier-Neto, Rafael; Baptista Junior, Sidney; Lima, Luciano Romero; Takata, Reinaldo Issao; Vargas, Antonio Pedro

    2017-01-01

    ABSTRACT The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. Objective: To report the relative frequency of common neuromuscular diagnoses in a reference center. Methods: A 17-year chart review of patients with suspicion of myopathy. Results: Among 3,412 examinations, 1,603 (46.98%) yielded confir...

  19. Frequency-dependent changes in the amplitude of low-frequency fluctuations in Internet gaming disorder

    Directory of Open Access Journals (Sweden)

    Xiao eLin

    2015-09-01

    Full Text Available Neuroimaging studies have revealed that the task-related functional brain activities are impaired in Internet gaming disorder (IGD subjects. However, little is known about the alternations in spontaneous brain activities about them. Recent studies have proposed that the brain activities of different frequency ranges are generated by different nervous activities and have different physiological and psychological functions. Thus, in this study, we set to explore the spontaneous brain activities in IGD subjects by measuring the fractional amplitude of low-frequency fluctuation (fALFF, to investigate band-specific changes of resting-state fALFF. We subdivided the frequency range into five bands based on literatures. Comparing to healthy controls, the IGD group showed decreased fALFF values in the cerebellum posterior lobe and increased fALFF values in superior temporal gyrus. Significant interactions between frequency bands and groups were found in the cerebellum, the anterior cingulate, the lingual gyrus, the middle temporal gyrus and the middle frontal gyrus. Those brain regions are proved related to the executive function and decision-making. These results revealed the changed spontaneous brain activity of IGD, which contributed to understanding the underlying pathophysiology of IGD.

  20. A matrix model for valuing anesthesia service with the resource-based relative value system.

    Science.gov (United States)

    Sinclair, David R; Lubarsky, David A; Vigoda, Michael M; Birnbach, David J; Harris, Eric A; Behrens, Vicente; Bazan, Richard E; Williams, Steve M; Arheart, Kristopher; Candiotti, Keith A

    2014-01-01

    The purpose of this study was to propose a new crosswalk using the resource-based relative value system (RBRVS) that preserves the time unit component of the anesthesia service and disaggregates anesthesia billing into component parts (preoperative evaluation, intraoperative management, and postoperative evaluation). The study was designed as an observational chart and billing data review of current and proposed payments, in the setting of a preoperative holing area, intraoperative suite, and post anesthesia care unit. In total, 1,195 charts of American Society of Anesthesiology (ASA) physical status 1 through 5 patients were reviewed. No direct patient interventions were undertaken. Spearman correlations between the proposed RBRVS billing matrix payments and the current ASA relative value guide methodology payments were strong (r=0.94-0.96, Pbilling matrix yielded payments that were 3.0%±1.34% less than would have been expected from commercial insurers, using standard rates for commercial ASA relative value units and RBRVS relative value units. Compared with current Medicare reimbursement under the ASA relative value guide, reimbursement would almost double when converting to an RBRVS billing model. The greatest increases in Medicare reimbursement between the current system and proposed billing model occurred as anesthetic management complexity increased. The new crosswalk correlates with existing evaluation and management and intensive care medicine codes in an essentially revenue neutral manner when applied to the market-based rates of commercial insurers. The new system more highly values delivery of care to more complex patients undergoing more complex surgery and better represents the true value of anesthetic case management.

  1. Percent relative cumulative frequency analysis in indirect calorimetry: application to studies of transgenic mice.

    Science.gov (United States)

    Riachi, Marc; Himms-Hagen, Jean; Harper, Mary-Ellen

    2004-12-01

    Indirect calorimetry is commonly used in research and clinical settings to assess characteristics of energy expenditure. Respiration chambers in indirect calorimetry allow measurements over long periods of time (e.g., hours to days) and thus the collection of large sets of data. Current methods of data analysis usually involve the extraction of only a selected small proportion of data, most commonly the data that reflects resting metabolic rate. Here, we describe a simple quantitative approach for the analysis of large data sets that is capable of detecting small differences in energy metabolism. We refer to it as the percent relative cumulative frequency (PRCF) approach and have applied it to the study of uncoupling protein-1 (UCP1) deficient and control mice. The approach involves sorting data in ascending order, calculating their cumulative frequency, and expressing the frequencies in the form of percentile curves. Results demonstrate the sensitivity of the PRCF approach for analyses of oxygen consumption (.VO2) as well as respiratory exchange ratio data. Statistical comparisons of PRCF curves are based on the 50th percentile values and curve slopes (H values). The application of the PRCF approach revealed that energy expenditure in UCP1-deficient mice housed and studied at room temperature (24 degrees C) is on average 10% lower (p lower environmental temperature, there were no differences in .VO2 between groups. The latter is likely due to augmented shivering thermogenesis in UCP1-deficient mice compared with controls. With the increased availability of murine models of metabolic disease, indirect calorimetry is increasingly used, and the PRCF approach provides a novel and powerful means for data analysis.

  2. Characterization of Anodized Titanium Based Novel Paradigm Supercapacitors: Impact of Salt Identity and Frequency on Dielectric Values, Power, and Energy Densities

    Science.gov (United States)

    2017-03-01

    solution, sufficient charge carriers to counteract the applied but not cause ion- lock , are energy densities at their maximum. For the salt identities and...OF ANODIZED TITANIUM- BASED NOVEL PARADIGM SUPERCAPACITORS: IMPACT OF SALT IDENTITY AND FREQUENCY ON DIELECTRIC VALUES, POWER, AND ENERGY DENSITIES...SUBTITLE CHARACTERIZATION OF ANODIZED TITANIUM-BASED NOVEL PARADIGM SUPERCAPACITORS: IMPACT OF SALT IDENTITY AND FREQUENCY ON DIELECTRIC VALUES, POWER

  3. The relative value of growth.

    Science.gov (United States)

    Mass, Nathaniel J

    2005-04-01

    Most executives would say that adding a point of growth and gaining a point of operating-profit margin contribute about equally to shareholder value. Margin improvements hit the bottom line immediately, while growth compounds value over time. But the reality is that the two are rarely equivalent. Growth often is far more valuable than managers think. For some companies, convincing the market that they can grow by just one additional percentage point can be worth six, seven, or even ten points of margin improvement. This article presents a new strategic metric, called the relative value of growth (RVG), which gives managers a clear picture of how growth projects and margin improvement initiatives affect shareholder value. Using basic balance sheet and income sheet data, managers can determine their companies' RVGs, as well as those of their competitors. Calculating RVGs gives managers insights into which corporate strategies are working to deliver value and whether their companies are pulling the most powerful value-creation levers. The author examines a number of well-known companies and explains what their RVG numbers say about their strategies. He reviews the unspoken assumption that growth and profits are incompatible over the long term and shows that a fair number of companies are effective at delivering both. Finally, he explains how managers can use the RVG framework to help them define strategies that balance growth and profitability at both the corporate and business unit levels.

  4. Magnitudes and frequencies of earthquakes in relation to seismic risk

    International Nuclear Information System (INIS)

    Sharma, R.D.

    1989-01-01

    Estimating the frequencies of occurrence of earthquakes of different magnitudes on a regional basis is an important task in estimating seismic risk at a construction site. Analysis of global earthquake data provides an insight into the magnitudes frequency relationship in a statistical manner. It turns out that, whereas a linear relationship between the logarithm of earthquake occurrence rates and the corresponding earthquake magnitudes fits well in the magnitude range between 5 and 7, a second degree polynomial in M, the earthquake magnitude provides a better description of the frequencies of earthquakes in a much wider range of magnitudes. It may be possible to adopt magnitude frequency relation for regions, for which adequate earthquake data are not available, to carry out seismic risk calculations. (author). 32 refs., 8 tabs., 7 figs

  5. On the relation between activity-related frequency shifts and the sunspot distribution over the solar cycle 23

    Directory of Open Access Journals (Sweden)

    Santos Ângela R. G.

    2017-01-01

    Full Text Available The activity-related variations in the solar acoustic frequencies have been known for 30 years. However, the importance of the different contributions is still not well established. With this in mind, we developed an empirical model to estimate the spot-induced frequency shifts, which takes into account the sunspot properties, such as area and latitude. The comparison between the model frequency shifts obtained from the daily sunspot records and those observed suggests that the contribution from a stochastic component to the total frequency shifts is about 30%. The remaining 70% is related to a global, long-term variation. We also propose a new observable to investigate the short-and mid-term variations of the frequency shifts, which is insensitive to the long-term variations contained in the data. On the shortest time scales the variations in the frequency shifts are strongly correlated with the variations in the total area covered by sunspots. However, a significant loss of correlation is still found, which cannot be fully explained by ignoring the invisible side of the Sun when accounting for the total sunspot area. We also verify that the times when the frequency shifts and the sunspot areas do not vary in a similar way tend to coincide with the times of the maximum amplitude of the quasi-biennial variations found in the seismic data.

  6. The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents.

    Science.gov (United States)

    Lee, Jung Ah; Lee, Sungkyu; Cho, Hong-Jun

    2017-03-14

    The prevalence of adolescent electronic cigarette (e-cigarette) use has increased in most countries. This study aims to determine the relation between the frequency of e-cigarette use and the frequency and intensity of cigarette smoking. Additionally, the study evaluates the association between the reasons for e-cigarette use and the frequency of its use. Using the 2015 Korean Youth Risk Behavior Web-Based Survey, we included 6655 adolescents with an experience of e-cigarette use who were middle and high school students aged 13-18 years. We compared smoking experience, the frequency and intensity of cigarette smoking, and the relation between the reasons for e-cigarette uses and the frequency of e-cigarette use. The prevalence of e-cigarette ever and current (past 30 days) users were 10.1% and 3.9%, respectively. Of the ever users, approximately 60% used e-cigarettes not within 1 month. On the other hand, 8.1% used e-cigarettes daily. The frequent and intensive cigarette smoking was associated with frequent e-cigarette uses. The percentage of frequent e-cigarette users (≥10 days/month) was 3.5% in adolescents who did not smoke within a month, but 28.7% among daily smokers. Additionally, it was 9.1% in smokers who smoked less than 1 cigarette/month, but 55.1% in smokers who smoked ≥20 cigarettes/day. The most common reason for e-cigarette use was curiosity (22.9%), followed by the belief that they are less harmful than conventional cigarettes (18.9%), the desire to quit smoking (13.1%), and the capacity for indoor use (10.7%). Curiosity was the most common reason among less frequent e-cigarette users; however, the desire to quit smoking and the capacity for indoor use were the most common reasons among more frequent users. Results showed a positive relation between frequency or intensity of conventional cigarette smoking and the frequency of e-cigarette use among Korean adolescents, and frequency of e-cigarette use differed according to the reason for the use of

  7. Systematic review on the prevalence, frequency and comparative value of adverse events data in social media

    Science.gov (United States)

    Golder, Su; Norman, Gill; Loke, Yoon K

    2015-01-01

    Aim The aim of this review was to summarize the prevalence, frequency and comparative value of information on the adverse events of healthcare interventions from user comments and videos in social media. Methods A systematic review of assessments of the prevalence or type of information on adverse events in social media was undertaken. Sixteen databases and two internet search engines were searched in addition to handsearching, reference checking and contacting experts. The results were sifted independently by two researchers. Data extraction and quality assessment were carried out by one researcher and checked by a second. The quality assessment tool was devised in-house and a narrative synthesis of the results followed. Results From 3064 records, 51 studies met the inclusion criteria. The studies assessed over 174 social media sites with discussion forums (71%) being the most popular. The overall prevalence of adverse events reports in social media varied from 0.2% to 8% of posts. Twenty-nine studies compared the results from searching social media with using other data sources to identify adverse events. There was general agreement that a higher frequency of adverse events was found in social media and that this was particularly true for ‘symptom’ related and ‘mild’ adverse events. Those adverse events that were under-represented in social media were laboratory-based and serious adverse events. Conclusions Reports of adverse events are identifiable within social media. However, there is considerable heterogeneity in the frequency and type of events reported, and the reliability or validity of the data has not been thoroughly evaluated. PMID:26271492

  8. The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents

    OpenAIRE

    Jung Ah Lee; Sungkyu Lee; Hong-Jun Cho

    2017-01-01

    Introduction: The prevalence of adolescent electronic cigarette (e-cigarette) use has increased in most countries. This study aims to determine the relation between the frequency of e-cigarette use and the frequency and intensity of cigarette smoking. Additionally, the study evaluates the association between the reasons for e-cigarette use and the frequency of its use. Materials and Methods: Using the 2015 Korean Youth Risk Behavior Web-Based Survey, we included 6655 adolescents with an exper...

  9. Values, inter-attitudinal structure, and attitude change: value accessibility can increase a related attitude's resistance to change.

    Science.gov (United States)

    Blankenship, Kevin L; Wegener, Duane T; Murray, Renee A

    2015-12-01

    Accessibility is one of the most basic structural properties of an attitude and an important factor to consider in attitude strength. Despite its importance, relatively little work has examined the role of attitude accessibility in an inter-attitudinal context, particularly as it relates to the strength of related attitudes in the network. The present research examines accessibility as a property of one attitude (toward an abstract goal or end-state, that is, a value) that might influence the strength of a different but related attitude (toward a social policy conceptually related to the value). In Study 1, a highly accessible evaluative component of a value increased resistance to change of attitudes and behavioral intentions toward a social policy related to that value. Similarly, a manipulation of value accessibility (Studies 2 and 3) led to increased resistance of attitudes and behavioral intentions toward a social policy related to that value. Implications for the role of accessibility in inter-attitudinal strength are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

  10. To IO-3 type instrument for measuring relative deviation of mean frequency

    International Nuclear Information System (INIS)

    Albats, Ya.Eh.; Bitite, Ya.A.; Ivanov, G.M.; Karpel'tseva, L.P.; Tesnavs, Eh.R.; Shuvtsan, Ya.V.

    1979-01-01

    A description is given of the 10-3 instrument intended for automatic measurement of a relative deviation of the pulse flow mean frequency from the preset value with digital presentation of measurement results, and also for the conversion of this relative deviation into an electric coded signal and in an analogue voltage signal. The 10-3 instrument comprises a master pulse generator, two preliminary scalers, two electronic switches, two storage pulse counters, control devices, a counter digital volume setter, a rewriting device, an internal storage, a digital display, and a digital-to-analog converter. The principle of the instrument operation consists in counting the pulses of measured and reference pulse flows by two storage counters. Basic performances of the instrument are given. The main advantage of the 10-3 instrument lies in the fact that it presents the results of measuring by a digital radioisotope instrument directly in physical units of the measured parameter, and that, in turn, obviates the necessity for additional mathematical operations when data processing [ru

  11. Long-term memory of relative reward values.

    Science.gov (United States)

    Soldati, Francesca; Burman, Oliver H P; John, Elizabeth A; Pike, Thomas W; Wilkinson, Anna

    2017-02-01

    Long-term memory can be adaptive as it allows animals to retain information that is crucial for survival, such as the appearance and location of key resources. This is generally examined by comparing choices of stimuli that have value to the animal with those that do not; however, in nature choices are rarely so clear cut. Animals are able to assess the relative value of a resource via direct comparison, but it remains unclear whether they are able to retain this information for a biologically meaningful amount of time. To test this, captive red-footed tortoises (Chelonoidis carbonaria) were first trained to associate visual cues with specific qualities and quantities of food, and their preferences for the different reward values determined. They were then retested after an interval of 18 months. We found that the tortoises were able to retain the information they had learned about the cues as indicators of relative reward values over this interval, demonstrating a memory for the relative quantity and quality of food over an extended period of time. This is likely to impact directly on an animal's foraging decisions, such as the exploitation of seasonally varying resources, with obvious fitness implications for the individual; however, the implications may also extend to the ecological interactions in which the animal is involved, affecting processes such as herbivory and seed dispersal. © 2017 The Author(s).

  12. Environmental Values related to fish and wildlife lands

    Science.gov (United States)

    David N. Bengston

    2000-01-01

    THe purpose of this paper is to provide an overview of key concepts related to environmental values and their importance for public land managers. The following section defines environmental values and discusses their relationship to environmnetal attitudes and beliefs. This is followed by presentation of a broad system for classifying environmental values and...

  13. Applying Novel Time-Frequency Moments Singular Value Decomposition Method and Artificial Neural Networks for Ballistocardiography

    Directory of Open Access Journals (Sweden)

    Koivistoinen Teemu

    2007-01-01

    Full Text Available As we know, singular value decomposition (SVD is designed for computing singular values (SVs of a matrix. Then, if it is used for finding SVs of an -by-1 or 1-by- array with elements representing samples of a signal, it will return only one singular value that is not enough to express the whole signal. To overcome this problem, we designed a new kind of the feature extraction method which we call ''time-frequency moments singular value decomposition (TFM-SVD.'' In this new method, we use statistical features of time series as well as frequency series (Fourier transform of the signal. This information is then extracted into a certain matrix with a fixed structure and the SVs of that matrix are sought. This transform can be used as a preprocessing stage in pattern clustering methods. The results in using it indicate that the performance of a combined system including this transform and classifiers is comparable with the performance of using other feature extraction methods such as wavelet transforms. To evaluate TFM-SVD, we applied this new method and artificial neural networks (ANNs for ballistocardiogram (BCG data clustering to look for probable heart disease of six test subjects. BCG from the test subjects was recorded using a chair-like ballistocardiograph, developed in our project. This kind of device combined with automated recording and analysis would be suitable for use in many places, such as home, office, and so forth. The results show that the method has high performance and it is almost insensitive to BCG waveform latency or nonlinear disturbance.

  14. The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents

    Directory of Open Access Journals (Sweden)

    Jung Ah Lee

    2017-03-01

    Full Text Available Introduction: The prevalence of adolescent electronic cigarette (e-cigarette use has increased in most countries. This study aims to determine the relation between the frequency of e-cigarette use and the frequency and intensity of cigarette smoking. Additionally, the study evaluates the association between the reasons for e-cigarette use and the frequency of its use. Materials and Methods: Using the 2015 Korean Youth Risk Behavior Web-Based Survey, we included 6655 adolescents with an experience of e-cigarette use who were middle and high school students aged 13–18 years. We compared smoking experience, the frequency and intensity of cigarette smoking, and the relation between the reasons for e-cigarette uses and the frequency of e-cigarette use. Results: The prevalence of e-cigarette ever and current (past 30 days users were 10.1% and 3.9%, respectively. Of the ever users, approximately 60% used e-cigarettes not within 1 month. On the other hand, 8.1% used e-cigarettes daily. The frequent and intensive cigarette smoking was associated with frequent e-cigarette uses. The percentage of frequent e-cigarette users (≥10 days/month was 3.5% in adolescents who did not smoke within a month, but 28.7% among daily smokers. Additionally, it was 9.1% in smokers who smoked less than 1 cigarette/month, but 55.1% in smokers who smoked ≥20 cigarettes/day. The most common reason for e-cigarette use was curiosity (22.9%, followed by the belief that they are less harmful than conventional cigarettes (18.9%, the desire to quit smoking (13.1%, and the capacity for indoor use (10.7%. Curiosity was the most common reason among less frequent e-cigarette users; however, the desire to quit smoking and the capacity for indoor use were the most common reasons among more frequent users. Conclusions: Results showed a positive relation between frequency or intensity of conventional cigarette smoking and the frequency of e-cigarette use among Korean adolescents, and

  15. Assessment of frequency of diarrhoea in relation to drinking water among residents of Nurpur Shahan, Pakistan.

    Science.gov (United States)

    Kakakhel, Zainab Masroor; Ibrar, Somabia; Khan, Wasim Alam; Bibi, Hajera; Zamir, Syed Ahmed; Khan, Shafin Sohail; Khan, Shabaz; Khan, Sohrab; Tariq, Wasif; Tahir, M Hassan; Iqbal, Saima

    2011-09-01

    To determine the source of drinking water and to assess its relationship with the frequency of diarrhoea among households of Nurpur Shahan. A cross-sectional descriptive study was carried out in January 2010 with a preformed questionnaire. Systematic random sampling was used to collect data. Participants' consent was obtained and confidentiality was maintained during the survey and during analysis. Households were evaluated for the frequency of diarrhoea in relation to their water source, its purification, and availability of sanitation facilities. All collected data was analyzed using SPSS 10.0. Of the 107 households surveyed, 2.8% used wells, 63% used tap water and 32.7% used hand pumps, whereas only 0.9% consumed store-bought water as their major source of drinking water. The difference in the frequency of diarrhoea between those households who purified their water and those that did not was just 1%. The relationship between the source of drinking water and the frequency of diarrhoea was not statistically significant (p = 0.319). Surprisingly households with no disposal facilities only had a 20% frequency of diarrhoea; this was found to be statistically significant (p = 0.023). This study contradicts the general conception that water supply is responsible for diarrhoea in the locality of Nurpur Shahan; it was found that the statistical difference between diarrhoea resulting from purified and non purified water was very small (p-value=0.587). Rather, improper sanitation and poor personal hygiene seem largely responsible for diarrhoea in this rural Islamabad community.

  16. The frequency of gestational diyabetes mellitus in a maternity hospital antepartum clinic

    Directory of Open Access Journals (Sweden)

    Abdulkadir Turgut

    2011-09-01

    Full Text Available Objectives: The aim of this study was to determine gestational diabetes mellitus (GDM frequency and age related frequency with GDM screening tests in patients whom referred to our hospital’s antepartum clinic for routine follow-up.Materials and methods: Totally, 2617 pregnant women who did not have any risk factors for GDM and attended to our antepartum clinic for routine follow-up between August 2009 and March 2011 enrolled in this study. A 50-g glucose challenge test (GCT applied at 24-28 weeks’ gestation. The patients who had a value of blood glucose ≥ 140 mg/dl undergone 100-g oral glucose tolerance test (OGTT. Patients who had a value of ≥200 mg/dl blood glucose in GCT or one value of ≥200 mg/dl in OGTT or had two values exceeded normal ranges in OGTT were accepted as GDM. Age related GDM frequency was also determined.Results: Of the 2617 pregnant women 110 patients diagnosed as GDM (4.2%. For the age related frequency, there was a tendency towards GDM after the age of 33. The age 44 was the most risky with a 33% ratio of GDM occurrence rate.Conclusion: In this study the GDM frequency in our hospital’s routine follow-up clinic was found as compatible with the 1% to 6% frequency reported in the literature. The higher frequency of GDM was found in advanced age pregnancies.

  17. A matrix model for valuing anesthesia service with the resource-based relative value system

    Directory of Open Access Journals (Sweden)

    Sinclair DR

    2014-10-01

    Full Text Available David R Sinclair,1 David A Lubarsky,1 Michael M Vigoda,1 David J Birnbach,1 Eric A Harris,1 Vicente Behrens,1 Richard E Bazan,1 Steve M Williams,1 Kristopher Arheart,2 Keith A Candiotti1 1Department of Anesthesiology, Perioperative Medicine and Pain Management, 2Department of Public Health Sciences, Division of Biostatistics, University of Miami Miller School of Medicine, Miami, FL, USA Background: The purpose of this study was to propose a new crosswalk using the resource-based relative value system (RBRVS that preserves the time unit component of the anesthesia service and disaggregates anesthesia billing into component parts (preoperative evaluation, intraoperative management, and postoperative evaluation. The study was designed as an observational chart and billing data review of current and proposed payments, in the setting of a preoperative holing area, intraoperative suite, and post anesthesia care unit. In total, 1,195 charts of American Society of Anesthesiology (ASA physical status 1 through 5 patients were reviewed. No direct patient interventions were undertaken. Results: Spearman correlations between the proposed RBRVS billing matrix payments and the current ASA relative value guide methodology payments were strong (r=0.94–0.96, P<0.001 for training, test, and overall. The proposed RBRVS-based billing matrix yielded payments that were 3.0%±1.34% less than would have been expected from commercial insurers, using standard rates for commercial ASA relative value units and RBRVS relative value units. Compared with current Medicare reimbursement under the ASA relative value guide, reimbursement would almost double when converting to an RBRVS billing model. The greatest increases in Medicare reimbursement between the current system and proposed billing model occurred as anesthetic management complexity increased. Conclusion: The new crosswalk correlates with existing evaluation and management and intensive care medicine codes in an

  18. Relative frequency of Human T-cell Lymphotropic Virus I/II in HIV/AIDS patients

    Directory of Open Access Journals (Sweden)

    Mohsen Meidani

    2014-01-01

    Conclusion: In our survey, relative frequency of HTLV-I/II was 1.8% in HIV+ patients. This study reveals that relative frequency of HTLV-I/II in HIV positive patients is considerable but determining the need for screening of HTLV-I/II requires further investigation.

  19. The role of singular values of measured frequency response function matrix in modal damping estimation (Part I: Theory)

    OpenAIRE

    Pápai, Ferenc; Szűcs, István

    2015-01-01

    The singular value decomposition of the measured frequency response function matrix, as a very effective tool of experimental modal analysis is used over the last twenty-five years. The complex mode indication function has become a common numerical tool in processing experimental data. There are many references on the development of complex mode indication function including the enhanced mode indication function and its use together with the enhanced frequency response function to form spatia...

  20. The role of singular values of measured frequency response function matrix in modal damping estimation (Part II: Investigations)

    OpenAIRE

    Pápai, Ferenc; Szűcs, István

    2015-01-01

    The singular value decomposition of the measured frequency response function matrix, as a very effective tool of experimental modal analysis is used over the last twenty-five years. The complex mode indication function has become a common numerical tool in processing experimental data. There are many references on the development of complex mode indication function including the enhanced mode indication function and its use together with the enhanced frequency response function to form spatia...

  1. Applying Novel Time-Frequency Moments Singular Value Decomposition Method and Artificial Neural Networks for Ballistocardiography

    Directory of Open Access Journals (Sweden)

    Alpo Värri

    2007-01-01

    Full Text Available As we know, singular value decomposition (SVD is designed for computing singular values (SVs of a matrix. Then, if it is used for finding SVs of an m-by-1 or 1-by-m array with elements representing samples of a signal, it will return only one singular value that is not enough to express the whole signal. To overcome this problem, we designed a new kind of the feature extraction method which we call ‘‘time-frequency moments singular value decomposition (TFM-SVD.’’ In this new method, we use statistical features of time series as well as frequency series (Fourier transform of the signal. This information is then extracted into a certain matrix with a fixed structure and the SVs of that matrix are sought. This transform can be used as a preprocessing stage in pattern clustering methods. The results in using it indicate that the performance of a combined system including this transform and classifiers is comparable with the performance of using other feature extraction methods such as wavelet transforms. To evaluate TFM-SVD, we applied this new method and artificial neural networks (ANNs for ballistocardiogram (BCG data clustering to look for probable heart disease of six test subjects. BCG from the test subjects was recorded using a chair-like ballistocardiograph, developed in our project. This kind of device combined with automated recording and analysis would be suitable for use in many places, such as home, office, and so forth. The results show that the method has high performance and it is almost insensitive to BCG waveform latency or nonlinear disturbance.

  2. Applying Novel Time-Frequency Moments Singular Value Decomposition Method and Artificial Neural Networks for Ballistocardiography

    Science.gov (United States)

    Akhbardeh, Alireza; Junnila, Sakari; Koivuluoma, Mikko; Koivistoinen, Teemu; Värri, Alpo

    2006-12-01

    As we know, singular value decomposition (SVD) is designed for computing singular values (SVs) of a matrix. Then, if it is used for finding SVs of an [InlineEquation not available: see fulltext.]-by-1 or 1-by- [InlineEquation not available: see fulltext.] array with elements representing samples of a signal, it will return only one singular value that is not enough to express the whole signal. To overcome this problem, we designed a new kind of the feature extraction method which we call ''time-frequency moments singular value decomposition (TFM-SVD).'' In this new method, we use statistical features of time series as well as frequency series (Fourier transform of the signal). This information is then extracted into a certain matrix with a fixed structure and the SVs of that matrix are sought. This transform can be used as a preprocessing stage in pattern clustering methods. The results in using it indicate that the performance of a combined system including this transform and classifiers is comparable with the performance of using other feature extraction methods such as wavelet transforms. To evaluate TFM-SVD, we applied this new method and artificial neural networks (ANNs) for ballistocardiogram (BCG) data clustering to look for probable heart disease of six test subjects. BCG from the test subjects was recorded using a chair-like ballistocardiograph, developed in our project. This kind of device combined with automated recording and analysis would be suitable for use in many places, such as home, office, and so forth. The results show that the method has high performance and it is almost insensitive to BCG waveform latency or nonlinear disturbance.

  3. What Cultural Values Influence American Public Relations Practitioners?

    Science.gov (United States)

    Vasquez, Gabriel M.; Taylor, Maureen

    1999-01-01

    Examines the role of culture as a key variable in public relations research and practice. Finds (1) American practitioners continue to practice one-way models of public relations; and (2) public relations practitioners who have collectivistic values tend to practice two-way models of public relations. Discusses implications for theory and…

  4. Frequency of consumption of products with varying energy value by patients of a sanatorium in Ciechocinek.

    Science.gov (United States)

    Górecka, Danuta; Szczepaniak, Barbara; Flaczyk, Ewa; Kordubski, Piotr

    2007-01-01

    The aim of the study was to assess the frequency of consumption of selected groups of foodstuffs with varying energy value by patients of the "Dom Zdrojowy" sanatorium in Ciechocinek (Poland). The survey included 100 persons, out of which 80% were obese individuals (OB), while the others were patients with cardiovascular diseases (CVD). Products with lowered energy value, especially cottage cheese, milk, "light" yogurt, as well as tea and coffee without sugar were on average consumed rather frequently. Obese patients, from among women constituted 80%, paid attention to fat content in their daily diet.

  5. Estimation of muscle fatigue by ratio of mean frequency to average rectified value from surface electromyography.

    Science.gov (United States)

    Fernando, Jeffry Bonar; Yoshioka, Mototaka; Ozawa, Jun

    2016-08-01

    A new method to estimate muscle fatigue quantitatively from surface electromyography (EMG) is proposed. The ratio of mean frequency (MNF) to average rectified value (ARV) is used as the index of muscle fatigue, and muscle fatigue is detected when MNF/ARV falls below a pre-determined or pre-calculated baseline. MNF/ARV gives larger distinction between fatigued muscle and non-fatigued muscle. Experiment results show the effectiveness of our method in estimating muscle fatigue more correctly compared to conventional methods. An early evaluation based on the initial value of MNF/ARV and the subjective time when the subjects start feeling the fatigue also indicates the possibility of calculating baseline from the initial value of MNF/ARV.

  6. Influence of modulation frequency in rubidium cell frequency standards

    Science.gov (United States)

    Audoin, C.; Viennet, J.; Cyr, N.; Vanier, J.

    1983-01-01

    The error signal which is used to control the frequency of the quartz crystal oscillator of a passive rubidium cell frequency standard is considered. The value of the slope of this signal, for an interrogation frequency close to the atomic transition frequency is calculated and measured for various phase (or frequency) modulation waveforms, and for several values of the modulation frequency. A theoretical analysis is made using a model which applies to a system in which the optical pumping rate, the relaxation rates and the RF field are homogeneous. Results are given for sine-wave phase modulation, square-wave frequency modulation and square-wave phase modulation. The influence of the modulation frequency on the slope of the error signal is specified. It is shown that the modulation frequency can be chosen as large as twice the non-saturated full-width at half-maximum without a drastic loss of the sensitivity to an offset of the interrogation frequency from center line, provided that the power saturation factor and the amplitude of modulation are properly adjusted.

  7. Real-time, high frequency QRS electrocardiograph with reduced amplitude zone detection

    Science.gov (United States)

    Schlegel, Todd T. (Inventor); DePalma, Jude L. (Inventor); Moradi, Saeed (Inventor)

    2009-01-01

    Real time cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed in real time in a useful form on a computer screen or monitor. The monitor displays the high frequency data from the QRS complex in units of microvolts, juxtaposed with a display of conventional ECG data in units of millivolts or microvolts. The high frequency data are analyzed for their root mean square (RMS) voltage values and the discrete RMS values and related parameters are displayed in real time. The high frequency data from the QRS complex are analyzed with imbedded algorithms to determine the presence or absence of reduced amplitude zones, referred to herein as ''RAZs''. RAZs are displayed as ''go, no-go'' signals on the computer monitor. The RMS and related values of the high frequency components are displayed as time varying signals, and the presence or absence of RAZs may be similarly displayed over time.

  8. INVESTIGATION OF THE FREQUENCY-TEMPERATURE RELATIONSHIP OF THE DIELECTRIC PERMITTIVITY OF THE PZT PIEZOCERAMICS IN THE LOW FREQUENCY RANGE

    Directory of Open Access Journals (Sweden)

    A. I. ZOLOTAREVSKIY

    2018-05-01

    Full Text Available Purpose. To investigate the frequency-temperature relationship of the dielectric permittivity of PZT piezoceramics in the low frequency range. Methodology. To obtain the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics, a technique was used to determine the capacitance of the capacitor, between which plates the sample was placed. The value of the dielectric permittivity of the sample was calculated from the capacitor capacitance obtained. Findings. The frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low frequency range has been obtained by the authors. The dielectric permittivity is not practically related to the frequency of the alternating voltage at a low temperature, with increasing in temperature its value increases and frequency relationship is observed. The temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by the exponential functional dependence in the low-temperature range. The activation energy of the PZT piezoceramics polarization is determined from the graph of the dependence of the logarithm of the dielectric permittivity upon the inverse temperature. Different values of the activation energy for the two temperature regions prove on the existence of different mechanisms of the PZT piezoceramics polarization in the temperature range being investigated. Originality. The authors investigated the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low-frequency range. It is established that the temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by an exponential functional relationship in the lowtemperature range. The activation energy of polarization is determined for two temperature sections. Practical value. The research results can be used to study the mechanism of polarization of

  9. Value of Frequency Domain Resting-State Functional Magnetic Resonance Imaging Metrics Amplitude of Low-Frequency Fluctuation and Fractional Amplitude of Low-Frequency Fluctuation in the Assessment of Brain Tumor-Induced Neurovascular Uncoupling.

    Science.gov (United States)

    Agarwal, Shruti; Lu, Hanzhang; Pillai, Jay J

    2017-08-01

    The aim of this study was to explore whether the phenomenon of brain tumor-related neurovascular uncoupling (NVU) in resting-state blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) (rsfMRI) may also affect the resting-state fMRI (rsfMRI) frequency domain metrics the amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF). Twelve de novo brain tumor patients, who underwent clinical fMRI examinations, including task-based fMRI (tbfMRI) and rsfMRI, were included in this Institutional Review Board-approved study. Each patient displayed decreased/absent tbfMRI activation in the primary ipsilesional (IL) sensorimotor cortex in the absence of a corresponding motor deficit or suboptimal task performance, consistent with NVU. Z-score maps for the motor tasks were obtained from general linear model analysis (reflecting motor activation vs. rest). Seed-based correlation analysis (SCA) maps of sensorimotor network, ALFF, and fALFF were calculated from rsfMRI data. Precentral and postcentral gyri in contralesional (CL) and IL hemispheres were parcellated using an automated anatomical labeling template for each patient. Region of interest (ROI) analysis was performed on four maps: tbfMRI, SCA, ALFF, and fALFF. Voxel values in the CL and IL ROIs of each map were divided by the corresponding global mean of ALFF and fALFF in the cortical brain tissue. Group analysis revealed significantly decreased IL ALFF (p = 0.02) and fALFF (p = 0.03) metrics compared with CL ROIs, consistent with similar findings of significantly decreased IL BOLD signal for tbfMRI (p = 0.0005) and SCA maps (p = 0.0004). The frequency domain metrics ALFF and fALFF may be markers of lesion-induced NVU in rsfMRI similar to previously reported alterations in tbfMRI activation and SCA-derived resting-state functional connectivity maps.

  10. Absolutely relative or relatively absolute: violations of value invariance in human decision making.

    Science.gov (United States)

    Teodorescu, Andrei R; Moran, Rani; Usher, Marius

    2016-02-01

    Making decisions based on relative rather than absolute information processing is tied to choice optimality via the accumulation of evidence differences and to canonical neural processing via accumulation of evidence ratios. These theoretical frameworks predict invariance of decision latencies to absolute intensities that maintain differences and ratios, respectively. While information about the absolute values of the choice alternatives is not necessary for choosing the best alternative, it may nevertheless hold valuable information about the context of the decision. To test the sensitivity of human decision making to absolute values, we manipulated the intensities of brightness stimuli pairs while preserving either their differences or their ratios. Although asked to choose the brighter alternative relative to the other, participants responded faster to higher absolute values. Thus, our results provide empirical evidence for human sensitivity to task irrelevant absolute values indicating a hard-wired mechanism that precedes executive control. Computational investigations of several modelling architectures reveal two alternative accounts for this phenomenon, which combine absolute and relative processing. One account involves accumulation of differences with activation dependent processing noise and the other emerges from accumulation of absolute values subject to the temporal dynamics of lateral inhibition. The potential adaptive role of such choice mechanisms is discussed.

  11. Sensitivity studies of a seismically isolated system to low frequency amplification

    International Nuclear Information System (INIS)

    Wu, T.S.; Seidensticker, R.W.

    1987-06-01

    Responses of a seismically isolated structure to earthquake motions will depend primarily on the input ground motion and the isolation system frequency. The isolation frequency generally is relatively low when isolating against horizontal ground motions. After installation, the isolation frequency could deviate from its designed value due to aging, manufacturing tolerance etc. In addition, under cettain soil conditions, the input motion could have high energy content at relatively low frequencies. This report covers the first of these two concerns by performing a sensitivity study of the variations in isolation frequency on the responses of a nuclear reactor module incorporated with an isolation system. Results from a number of ground motions have shown that, for most earthquake motions, a higher isolation frequency tends to yield higher maximum acceleration, higher transmitted shear force, and lower relative displacement between the isolated and unisolated parts of the structure. In one of the ground motions considered, a 7% increase in the isolation frequency from its original design value is observed to give over a 22% increase in the transmitted shear force. Other ground motions, especially those exhibiting sharp rise in spectral accelerations in the vicinity of the designed isolated frequency, yield responses following the same general trend

  12. [Health-related quality of life assessment in depression after low-frequency transcranial magnetic stimulation].

    Science.gov (United States)

    Dumas, R; Boyer, L; Richieri, R; Guedj, E; Auquier, P; Lançon, C

    2014-02-01

    TMS treatment on the SF-36 and the clinical outcome was evaluated for significance with the Wilcoxon two-tailed signed-rank test. The reliable change index (RCI) was calculated to determine clinically significant change in the eight dimension and composite scores of the SF-36 from pre-intervention to post-intervention, at the level of individual patients. Effect size (r) was then calculated, r values from 0.1 to 0.29, 0.3 to 0.49 and from 0.5 were considered as indicating small, medium and large effect sizes, respectively. Correlations between improvement in Health-related Quality of Life and improvement in the other rating scale scores were calculated using Spearman's correlation test. There were significant improvements of 37.6% in the mental health (P=0.018), 130 % in the role-emotional problem (P=0.045), 15.5% in the physical functioning (P=0.008), 110.6% in the role-physical problem (P=0.002), 22.4% in the bodily pain (P=0.013) dimensions, 6.1% in the Physical Component Score (P=0.043), and 22,5 % in the Beck Depression Inventory (P=0.002). Eighteen patients (54%) showed clinically significant improvement in one of the two composite scores after RCI calculation. Seven out of the eight SF-36 dimension scores and the two composite scores showed effect sizes ranging from 0.12 to 0.38, indicating small to moderate effect. Significant correlations were found between improvement in the Beck Depression Inventory and improvement in the Mental Component Score, the social functioning, the mental health, the general health, the vitality and the physical functioning dimensions. Small sample size and non-controlled design. Low-frequency rTMS over the right dorsolateral prefrontal cortex improves Health-related Quality of Life in unipolar and bipolar patients with medication-resistant depression. Improvement in mental health-related quality of life is significantly correlated with improvement in depressive symptoms. However, further studies with larger samples and controlled designs are

  13. Minnesota anglers' fisheries-related value orientations and their stewardship of fish resources

    Science.gov (United States)

    Bruskotter, J.T.; Fulton, D.C.

    2008-01-01

    Research on natural resource-related values and value orientations has grown substantially over the past decade. However, existing studies have focused almost exclusively on value orientations related to wildlife and forests. This article reports data from two mail surveys of Minnesota anglers used to develop scales for measuring fisheries-related value orientations. We report results of regression analyses examining the relationship between anglers' value orientations and norms concerning fisheries stewardship and the use of technological aids to angling. Results indicate 10 items reliably measure three value orientations we termed utilitarianism, dominance, and protectionism. Regression analyses suggest anglers' stewardship norms are influenced by all three value orientation types, while support for the use of technological aids was related with protectionism and utilitarianism, but not dominance. Results suggest anglers' fisheries-related value orientations cannot be adequately captured using single domain scales. Implications for the study of natural resources-related value orientations are discussed. Copyright ?? Taylor & Francis Group, LLC.

  14. Temperature and frequency investigations of the electrical parameters in the TGS ferroelectric transition

    Energy Technology Data Exchange (ETDEWEB)

    Berbecaru, Ciceron [University of Bucharest, Faculty of Physics, Bucharest-Magurele 077125 (Romania)

    2010-05-15

    Pure and D: alanina doped triglycin sulphate (TGS) crystals were grown from aqueous solutions. Fresh cleaved, polished and silver paste painted samples were temperature and frequency investigated. Pure crystals show nonreproducible values of the permittivity and dielectric loss crossing up and down the Curie point. More stable and much lower values of the permittivity and dielectric loss could be noticed for D: alanina doped crystals. Permittivity and loss values show different frequencies behavior related to polar or nonpolar state of crystals. Frequency dependence of permittivity and loss behavior could be related to the general picture of relaxation of different polarization mechanisms and their contributions to permittivity and loss values for dielectric materials. Much smaller and stable values of permittivity and loss, vs. temperature and frequency, were found for doped crystals. Experimental results point out for a more stable structure with dipoles mobility decreased of doped vs. pure TGS crystals. Thus, higher figure of merit of doped TGS crystals point to a major advantage for technical applications (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Semantic priming increases word frequency judgments: Evidence for the role of memory strength in frequency estimation.

    Science.gov (United States)

    Woltz, Dan J; Gardner, Michael K

    2015-09-01

    Previous research has demonstrated a systematic, nonlinear relationship between word frequency judgments and values from word frequency norms. This relationship could reflect a perceptual process similar to that found in the psychophysics literature for a variety of sensory phenomena. Alternatively, it could reflect memory strength differences that are expected for words of varying levels of prior exposure. Two experiments tested the memory strength explanation by semantically priming words prior to frequency judgments. Exposure to related word meanings produced a small but measurable increase in target word frequency ratings. Repetition but not semantic priming had a greater impact on low compared to high frequency words. These findings are consistent with a memory strength view of frequency judgments that assumes a distributed network with lexical and semantic levels of representation. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Bimanual tapping of a syncopated rhythm reveals hemispheric preferences for relative movement frequencies.

    Science.gov (United States)

    Pflug, Anja; Gompf, Florian; Kell, Christian Alexander

    2017-08-01

    In bimanual multifrequency tapping, right-handers commonly use the right hand to tap the relatively higher rate and the left hand to tap the relatively lower rate. This could be due to hemispheric specializations for the processing of relative frequencies. An extension of the double-filtering-by-frequency theory to motor control proposes a left hemispheric specialization for the control of relatively high and a right hemispheric specialization for the control of relatively low tapping rates. We investigated timing variability and rhythmic accentuation in right handers tapping mono- and multifrequent bimanual rhythms to test the predictions of the double-filtering-by-frequency theory. Yet, hemispheric specializations for the processing of relative tapping rates could be masked by a left hemispheric dominance for the control of known sequences. Tapping was thus either performed in an overlearned quadruple meter (tap of the slow rhythm on the first auditory beat) or in a syncopated quadruple meter (tap of the slow rhythm on the fourth auditory beat). Independent of syncopation, the right hand outperformed the left hand in timing accuracy for fast tapping. A left hand timing benefit for slow tapping rates as predicted by the double-filtering-by-frequency theory was only found in the syncopated tapping group. This suggests a right hemisphere preference for the control of slow tapping rates when rhythms are not overlearned. Error rates indicate that overlearned rhythms represent hierarchically structured meters that are controlled by a single timer that could potentially reside in the left hemisphere. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Relative Frequencies of Arteritic and Nonarteritic Anterior Ischemic Optic Neuropathy in an Arab Population.

    Science.gov (United States)

    Gruener, Anna M; Chang, Jessica R; Bosley, Thomas M; Al-Sadah, Zakeya M; Kum, Clarissa; McCulley, Timothy J

    2017-12-01

    To evaluate the relative frequencies of arteritic and nonarteritic anterior ischemic optic neuropathy (AION) in an Arab population and to compare and contrast these findings with known epidemiological data from Caucasian populations. A retrospective review of the medical records of all patients diagnosed with AION at the King Khaled Eye Specialist Hospital (KKESH) in Riyadh, Saudi Arabia, between 1997 and 2012. Of 171 patients with AION, 4 had biopsy-proven giant-cell arteritis (GCA). The relative frequencies of arteritic anterior ischemic optic neuropathy (AAION) and nonarteritic anterior ischemic optic neuropathy (NAION) in this Arab cohort were 2.3% and 97.7%, respectively. The relative frequencies of arteritic anterior ischemic optic neuropathy and nonarteritic anterior ischemic optic neuropathy differ between Arab and North American clinic-based populations, with giant-cell arteritis-related ischemia being much less frequent in Saudi Arabia.

  18. Dispersion relation and self-collimation frequency of spoof surface plasmon using tight binding model

    International Nuclear Information System (INIS)

    Bhattacharya, Sayak; Shah, Kushal

    2015-01-01

    The analytical dispersion relation of spoof surface plasmon (SSP) is known only in the low-frequency limit and thus cannot be used to describe various practically important characteristics of SSP in the high-frequency limit (such as multimodal nature, anisotropic propagation, self-collimation). In this article, we consider a square lattice of holes made on a perfect electric conductor and derive a closed form expression of the SSP dispersion relation in the high-frequency limit using a tight binding model. Instead of using prior knowledge of the band diagram along the entire first Brillouin zone (BZ) edge, we analytically determine the hopping parameters by using the eigenfrequencies only at the three high-symmetry points of the square lattice. Using this dispersion relation, we derive an expression for the self-collimation frequency of SSP. We show that this analytical formulation is also applicable to dielectric photonic crystals and can be used to predict the frequencies corresponding to centimetre-scale supercollimation and second band self-collimation in these structures. Finally, we show that our analytical results are in agreement with the simulation results for both SSP and photonic crystals. (paper)

  19. Lucid Dreaming: Intensity, But Not Frequency, Is Inversely Related to Psychopathology

    Directory of Open Access Journals (Sweden)

    Liat Aviram

    2018-03-01

    Full Text Available Lucid dreaming (LD is awareness that one is dreaming, during the dream state. However, some define and assess LD relying also on controlling dream events, although control is present only in a subset of lucid dreams. LD has been claimed to represent well-being, and has even been used as a therapeutic agent. Conversely, LD is associated with mixed sleep-wake states, which are related to bizarre cognitions, stress, and psychopathology, and have been construed as arousal permeating and disrupting sleep. We propose that previous conflicting findings regarding relations between LD and both psychopathology and well-being, stem from the non-differentiated assessment of frequency and control. The present study aimed to develop an expansive measure of several LD characteristics (the Frequency and Intensity Lucid Dream questionnaire; FILD, and explore their relations with symptomatology. Undergraduate students (N = 187 self-reported trait LD, psychopathology (depression, anxiety, obsessive-compulsive symptoms, dissociation, and schizotypy, stress, and sleep problems; 2 months later, a subsample (n = 78 reported psychopathology again, and also completed a dream diary each morning for 14 days. Preliminary evidence supports the reliability and validity of the FILD. Items converged into four domains: frequency, intensity (e.g., control, activity, certainty of dreaming, emotional valence, and the use of induction techniques. We report an optimal frequency cutoff score to identify those likely to experience LD within a 2-week period. Whereas LD frequency was unrelated to psychopathology, LD intensity, and positive LD emotions, were inversely associated with several psychopathological symptoms. Use of deliberate induction techniques was positively associated with psychopathology and sleep problems. Additionally, we demonstrated directionality by employing a prospective-longitudinal design, showing that deliberate LD induction predicted an increase in

  20. Lucid Dreaming: Intensity, But Not Frequency, Is Inversely Related to Psychopathology

    Science.gov (United States)

    Aviram, Liat; Soffer-Dudek, Nirit

    2018-01-01

    Lucid dreaming (LD) is awareness that one is dreaming, during the dream state. However, some define and assess LD relying also on controlling dream events, although control is present only in a subset of lucid dreams. LD has been claimed to represent well-being, and has even been used as a therapeutic agent. Conversely, LD is associated with mixed sleep-wake states, which are related to bizarre cognitions, stress, and psychopathology, and have been construed as arousal permeating and disrupting sleep. We propose that previous conflicting findings regarding relations between LD and both psychopathology and well-being, stem from the non-differentiated assessment of frequency and control. The present study aimed to develop an expansive measure of several LD characteristics (the Frequency and Intensity Lucid Dream questionnaire; FILD), and explore their relations with symptomatology. Undergraduate students (N = 187) self-reported trait LD, psychopathology (depression, anxiety, obsessive-compulsive symptoms, dissociation, and schizotypy), stress, and sleep problems; 2 months later, a subsample (n = 78) reported psychopathology again, and also completed a dream diary each morning for 14 days. Preliminary evidence supports the reliability and validity of the FILD. Items converged into four domains: frequency, intensity (e.g., control, activity, certainty of dreaming), emotional valence, and the use of induction techniques. We report an optimal frequency cutoff score to identify those likely to experience LD within a 2-week period. Whereas LD frequency was unrelated to psychopathology, LD intensity, and positive LD emotions, were inversely associated with several psychopathological symptoms. Use of deliberate induction techniques was positively associated with psychopathology and sleep problems. Additionally, we demonstrated directionality by employing a prospective-longitudinal design, showing that deliberate LD induction predicted an increase in dissociation and

  1. The resource-based relative value scale and physician reimbursement policy.

    Science.gov (United States)

    Laugesen, Miriam J

    2014-11-01

    Most physicians are unfamiliar with the details of the Resource-Based Relative Value Scale (RBRVS) and how changes in the RBRVS influence Medicare and private reimbursement rates. Physicians in a wide variety of settings may benefit from understanding the RBRVS, including physicians who are employees, because many organizations use relative value units as productivity measures. Despite the complexity of the RBRVS, its logic and ideal are simple: In theory, the resource usage (comprising physician work, practice expense, and liability insurance premium costs) for one service is relative to the resource usage of all others. Ensuring relativity when new services are introduced or existing services are changed is, therefore, critical. Since the inception of the RBRVS, the American Medical Association's Relative Value Scale Update Committee (RUC) has made recommendations to the Centers for Medicare & Medicaid Services on changes to relative value units. The RUC's core focus is to develop estimates of physician work, but work estimates also partly determine practice expense payments. Critics have attributed various health-care system problems, including declining and growing gaps between primary care and specialist incomes, to the RUC's role in the RBRVS update process. There are persistent concerns regarding the quality of data used in the process and the potential for services to be overvalued. The Affordable Care Act addresses some of these concerns by increasing payments to primary care physicians, requiring reevaluation of the data underlying work relative value units, and reviewing misvalued codes.

  2. A dynamic model-based estimate of the value of a vanadium redox flow battery for frequency regulation in Texas

    International Nuclear Information System (INIS)

    Fares, Robert L.; Meyers, Jeremy P.; Webber, Michael E.

    2014-01-01

    Highlights: • A model is implemented to describe the dynamic voltage of a vanadium flow battery. • The model is used with optimization to maximize the utility of the battery. • A vanadium flow battery’s value for regulation service is approximately $1500/kW. - Abstract: Building on past work seeking to value emerging energy storage technologies in grid-based applications, this paper introduces a dynamic model-based framework to value a vanadium redox flow battery (VRFB) participating in Texas’ organized electricity market. Our model describes the dynamic behavior of a VRFB system’s voltage and state of charge based on the instantaneous charging or discharging power required from the battery. We formulate an optimization problem that incorporates the model to show the potential value of a VRFB used for frequency regulation service in Texas. The optimization is implemented in Matlab using the large-scale, interior-point, nonlinear optimization algorithm, with the objective function gradient, nonlinear constraint gradients, and Hessian matrix specified analytically. Utilizing market prices and other relevant data from the Electric Reliability Council of Texas (ERCOT), we find that a VRFB system used for frequency regulation service could be worth approximately $1500/kW

  3. High relative frequency of thyroid papillary carcinoma in northern Portugal.

    Science.gov (United States)

    Sambade, M C; Gonçalves, V S; Dias, M; Sobrinho-Simões, M A

    1983-05-01

    Two hundred and twelve papillary and 40 follicular carcinomas were found in 3002 thyroid glands examined from 1931 to 1975 in four Laboratories of Pathology that fairly cover northern Portugal. There was a striking preponderance of women both in papillary (female:male = 6.9:1) and follicular carcinoma (5.7:1). Sex-specific frequency of malignancy was significantly greater in men (13.3%) than in women (8.8%). The overall papillary/follicular ratio was 5.3:1 and did not significantly change throughout the study period. Papillary/follicular ratio was not significantly greater in litoral (5.5:1) than in regions with a low iodine intake and a relatively high prevalence of goiter (3.5:1). It is advanced that this high relative frequency of papillary carcinoma in northern Portugal, even in goiter areas, may reflect the existence of a racial factor since there is not enough evidence to support the influence of dietary iodine, previous irradiation and concurrent thyroiditis.

  4. [Clinical auxiliary diagnosis value of high frequency ultrasonographic measurements of the thickness of transverse carpal ligaments in carpal tunnel syndrome patients].

    Science.gov (United States)

    Xu, L; Chen, F M; Wang, L; Zhang, P X; Jiang, X R

    2016-04-18

    To evaluate the meaning and value of high-frequency ultrasound in the diagnosis of carpal tunnel syndrome (CTS). In this study, 48 patients (unilateral hand) with CTS were analyzed. The thickness of transverse carpal ligaments at the pisiform bone was measured using high-frequency ultrasound. Open carpal tunnel release procedure was performed in the 48 CTS patients, and the thickness of transverse carpal ligaments at the hamate hook bone measured using vernier caliper under direct vision. The accuracy of thickness of transverse carpal ligaments was evaluated using high-frequency ultrasound. high-frequency ultrasound measurement of thickness of transverse carpal ligaments at the hamate hook bone and pisiform bone, and determination of the diagnostic threshold measurement index using receiver operating characteristic (ROC) curve, sensitivity and specificity were performed and the correlation between the thickness of transverse carpal ligaments and nerve conduction study (NCS) analyzed. The thickness of transverse carpal ligaments in the CTS patients were (0.42±0.08) cm (high-frequency ultrasound) and (0.41±0.06) cm (operation) at hamate hook bone, and there was no significant difference between the two ways (t=0.672, P>0.05). The optimal cut-off value of the transverse carpal ligaments at hamate hook bone was 0.385 cm, the sensitivity 0.775, and the specificity 0.788. The optimal cut-off value of the transverse carpal ligaments at the pisiform bone was 0.315 cm, the sensitivity 0.950, and the specificity 1.000. The transverse carpal ligaments thickness and wrist-index finger sensory nerve conduction velocity (SCV), wrist-middle finger SCV showed a negative correlation. High frequency ultrasound measurements of thickness of transverse carpal ligaments is a valuable method for the diagnosis of CTS.

  5. Frequency, moisture content, and temperature dependent dielectric properties of potato starch related to drying with radio-frequency/microwave energy.

    Science.gov (United States)

    Zhu, Zhuozhuo; Guo, Wenchuan

    2017-08-24

    To develop advanced drying methods using radio-frequency (RF) or microwave (MW) energy, dielectric properties of potato starch were determined using an open-ended coaxial-line probe and network analyzer at frequencies between 20 and 4,500 MHz, moisture contents between 15.1% and 43.1% wet basis (w.b.), and temperatures between 25 and 75 °C. The results showed that both dielectric constant (ε') and loss factor (ε″) were dependent on frequency, moisture content, and temperature. ε' decreased with increasing frequency at a given moisture content or temperature. At low moisture contents (≤25.4% w.b.) or low temperatures (≤45 °C), ε″ increased with increasing frequency. However, ε″ changed from decrease to increase with increasing frequency at high moisture contents or temperatures. At low temperatures (25-35 °C), both ε' and ε″ increased with increasing moisture content. At low moisture contents (15.1-19.5% w.b.), they increased with increasing temperature. The change trends of ε' and ε″ were different and dependent on temperature and moisture content at their high levels. The penetration depth (d p ) decreased with increasing frequency. RF treatments may provide potential large-scale industrial drying application for potato starch. This research offers useful information on dielectric properties of potato starch related to drying with electromagnetic energy.

  6. Vibro-Shock Dynamics Analysis of a Tandem Low Frequency Resonator—High Frequency Piezoelectric Energy Harvester

    Directory of Open Access Journals (Sweden)

    Darius Žižys

    2017-04-01

    Full Text Available Frequency up-conversion is a promising technique for energy harvesting in low frequency environments. In this approach, abundantly available environmental motion energy is absorbed by a Low Frequency Resonator (LFR which transfers it to a high frequency Piezoelectric Vibration Energy Harvester (PVEH via impact or magnetic coupling. As a result, a decaying alternating output signal is produced, that can later be collected using a battery or be transferred directly to the electric load. The paper reports an impact-coupled frequency up-converting tandem setup with different LFR to PVEH natural frequency ratios and varying contact point location along the length of the harvester. RMS power output of different frequency up-converting tandems with optimal resistive values was found from the transient analysis revealing a strong relation between power output and LFR-PVEH natural frequency ratio as well as impact point location. Simulations revealed that higher power output is obtained from a higher natural frequency ratio between LFR and PVEH, an increase of power output by one order of magnitude for a doubled natural frequency ratio and up to 150% difference in power output from different impact point locations. The theoretical results were experimentally verified.

  7. Relative validity of a food frequency questionnaire to assess nutrient intake in pregnant women.

    Science.gov (United States)

    McGowan, C A; Curran, S; McAuliffe, F M

    2014-04-01

    To date, there are no food frequency questionnaires that have been validated to assess nutrient intakes in pregnant women in Ireland. The present study aimed to assess the relative validity of a self-administered food frequency questionnaire during pregnancy. The food frequency questionnaire was administered once during pregnancy between 12 and 34 weeks. Participants also completed a 3-day food diary during each trimester of pregnancy (reference method) and intakes from both the food frequency questionnaire and the mean of the 3-day food diaries were compared in a sample of 130 participants from the control arm of an intervention study. Energy-adjusted Pearson's correlation coefficients ranged from 0.24 (riboflavin) to 0.59 (magnesium) and were all statistically significant (P food frequency questionnaire tended to report higher energy and nutrient intakes compared to the food diaries. On average, 74% of participants were classified into the same ± 1 quartile and 7% into opposing quartiles by the two methods. Overall, our food frequency questionnaire showed good relative validity. We conclude that a single administration of a food frequency questionnaire is a valid tool for ranking women in accordance with their nutrient intakes during pregnancy. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.

  8. Event-related desynchronization and synchronization in MEG: Framework for analysis and illustrative datasets related to discrimination of frequency-modulated tones.

    Science.gov (United States)

    Zygierewicz, J; Sieluzycki, C; König, R; Durka, P J

    2008-02-15

    We introduce a complete framework for the calculation of statistically significant event-related desynchronization and synchronization (ERD/ERS) in the time-frequency plane for magnetoencephalographic (MEG) data, and provide free Internet access to software and illustrative datasets related to a classification task of frequency-modulated (FM) tones. Event-related changes in MEG were analysed on the basis of the normal component of the magnetic field acquired by the 148 magnetometers of the hardware configuration of our whole-head MEG device, and by computing planar gradients in longitudinal and latitudinal direction. Time-frequency energy density for the magnetometer as well as the two gradient configurations is first approximated using short-time Fourier transform. Subsequently, detailed information is obtained from high-resolution time-frequency maps for the most interesting sensors by means of the computationally much more demanding matching pursuit parametrization. We argue that the ERD/ERS maps are easier to interpret in the gradient approaches and discuss the superior resolution of the matching pursuit time-frequency representation compared to short-time Fourier and wavelet transforms. Experimental results are accompanied by the following resources, available from http://brain.fuw.edu.pl/MEG: (a) 48 high-resolution figures presenting the results of four subjects in all applicable settings, (b) raw datasets, and (c) complete software environment, allowing to recompute these figures from the raw datasets.

  9. On the frequency and field linewidth conversion of ferromagnetic resonance spectra

    International Nuclear Information System (INIS)

    Wei, Yajun; Svedlindh, Peter; Liang Chin, Shin

    2015-01-01

    Both frequency swept and field swept ferromagnetic resonance measurements have been carried out for a number of different samples with negligible, moderate and significant extrinsic frequency independent linewidth contribution to analyze the correlation between the experimentally measured frequency and field linewidths. Contrary to the belief commonly held by many researchers, it is found that the frequency and field linewidth conversion relation does not hold for all cases. Instead it holds only for samples with negligible frequency independent linewidth contributions. For samples with non-negligible frequency independent linewidth contribution, the field linewidth values converted from the measured frequency linewidth are larger than the experimentally measured field linewidth. A close examination of the literature reveals that previously reported results support our findings, with successful conversions related to samples with negligible frequency independent linewidth contributions and unsuccessful conversions related to samples with significant frequency independent linewidth. The findings are important in providing guidance in ferromagnetic resonance linewidth conversions. (paper)

  10. Phase coherence and Rabi frequency induced ultranarrow spectral line

    International Nuclear Information System (INIS)

    Dutta, Bibhas Kumar; Panchadhyayee, Pradipta; Mahapatra, Prasanta Kumar

    2012-01-01

    A scheme is proposed to achieve ultranarrow spectral line in the fluorescence spectrum of a lifetime broadened multilevel phase-coherent atom. It is shown that for weak-field coupling, ultranarrow spectral feature in the fluorescence spectrum can be generated by controlling the values of the Rabi frequencies involved in the coherent mechanism of the system. For fixed values of the Rabi frequencies in the weak-field limit, ultranarrow feature appears in the spectrum through the adjustment of the relative phase of the coherent fields. The results highlight that, larger the values of the decay rates associated with the field-driven channels, more pronounced is the phenomenon of narrowing in the spectrum.

  11. Failure frequencies and probabilities applicable to BWR and PWR piping

    International Nuclear Information System (INIS)

    Bush, S.H.; Chockie, A.D.

    1996-03-01

    This report deals with failure probabilities and failure frequencies of nuclear plant piping and the failure frequencies of flanges and bellows. Piping failure probabilities are derived from Piping Reliability Analysis Including Seismic Events (PRAISE) computer code calculations based on fatigue and intergranular stress corrosion as failure mechanisms. Values for both failure probabilities and failure frequencies are cited from several sources to yield a better evaluation of the spread in mean and median values as well as the widths of the uncertainty bands. A general conclusion is that the numbers from WASH-1400 often used in PRAs are unduly conservative. Failure frequencies for both leaks and large breaks tend to be higher than would be calculated using the failure probabilities, primarily because the frequencies are based on a relatively small number of operating years. Also, failure probabilities are substantially lower because of the probability distributions used in PRAISE calculations. A general conclusion is that large LOCA probability values calculated using PRAISE will be quite small, on the order of less than 1E-8 per year (<1E-8/year). The values in this report should be recognized as having inherent limitations and should be considered as estimates and not absolute values. 24 refs 24 refs

  12. Non-Relative Value Unit-Generating Activities Represent One-Fifth of Academic Neuroradiologist Productivity.

    Science.gov (United States)

    Wintermark, M; Zeineh, M; Zaharchuk, G; Srivastava, A; Fischbein, N

    2016-07-01

    A neuroradiologist's activity includes many tasks beyond interpreting relative value unit-generating imaging studies. Our aim was to test a simple method to record and quantify the non-relative value unit-generating clinical activity represented by consults and clinical conferences, including tumor boards. Four full-time neuroradiologists, working an average of 50% clinical and 50% academic activity, systematically recorded all the non-relative value unit-generating consults and conferences in which they were involved during 3 months by using a simple, Web-based, computer-based application accessible from smartphones, tablets, or computers. The number and type of imaging studies they interpreted during the same period and the associated relative value units were extracted from our billing system. During 3 months, the 4 neuroradiologists working an average of 50% clinical activity interpreted 4241 relative value unit-generating imaging studies, representing 8152 work relative value units. During the same period, they recorded 792 non-relative value unit-generating study reviews as part of consults and conferences (not including reading room consults), representing 19% of the interpreted relative value unit-generating imaging studies. We propose a simple Web-based smartphone app to record and quantify non-relative value unit-generating activities including consults, clinical conferences, and tumor boards. The quantification of non-relative value unit-generating activities is paramount in this time of a paradigm shift from volume to value. It also represents an important tool for determining staffing levels, which cannot be performed on the basis of relative value unit only, considering the importance of time spent by radiologists on non-relative value unit-generating activities. It may also influence payment models from medical centers to radiology departments or practices. © 2016 by American Journal of Neuroradiology.

  13. The web-based ASSO-food frequency questionnaire for adolescents: relative and absolute reproducibility assessment.

    Science.gov (United States)

    Filippi, Anna Rita; Amodio, Emanuele; Napoli, Giuseppe; Breda, João; Bianco, Antonino; Jemni, Monèm; Censi, Laura; Mammina, Caterina; Tabacchi, Garden

    2014-12-17

    A new food frequency questionnaire (FFQ) has been recently developed within the Italian Adolescents and Surveillance System for the Obesity prevention (ASSO) Project; it was found to be appropriate for ranking adolescents in food and nutrient levels of intake. The aim of this study was to assess the relative and absolute reproducibility of the ASSO-FFQ for 24 food groups, energy and 52 nutrients. A test-retest study was performed on two ASSO-FFQs administered one month apart of each other to 185 adolescents, aged 14-17 and attending secondary schools in Palermo (Italy). Wilcoxon test assessed differences in median daily intakes between the two FFQs. Agreement was evaluated by quintiles comparison and weighted kappa. Intraclass Correlation Coefficients (ICC) and Bland-Altman method assessed the relative and absolute reliability respectively. Significant difference (p food, water, soft drinks, carbohydrates and sugar. The subjects classified into the same or adjacent quintiles for food groups ranged from 62% (white bread) to 91% (soft drinks); for energy and nutrients from 64% (polyunsaturated fatty acids) to 90% (ethanol). Mean values of weighted kappa were 0.47 and 0.48, respectively for food groups and nutrients. Fair to good ICC values (>0.40) were assessed for thirteen food groups, energy and forty-three nutrients. Limits of Agreement were narrow for almost all food groups and all nutrients. The ASSO-FFQ is a reliable instrument for estimating food groups, energy and nutrients intake in adolescents.

  14. School Social Worker's Perceptions of the Frequency of Actual and Preferred Engagement in Role Related Activities

    Science.gov (United States)

    Arthur, Elizabeth

    2009-01-01

    The purpose of this study was (1) to determine the frequency in which school social workers in Virginia engage in and prefer to engage in social work related activities and (2) to determine if the frequency in which the social work related activities the school social workers engage in is related to select variables. After a comprehensive review…

  15. [Self-reported substance abuse related emergencies: frequency and nature].

    Science.gov (United States)

    Schäfer, G; Smoltczyk, H; Dengler, W; Buchkremer, G

    2000-04-01

    The aim of this study was to estimate the frequency and nature of self-reported and drug-related emergencies. 47 patients of a ward for opiate detoxification were interviewed about their experiences with drug-related emergencies. Typical categories had to be found like overdoses, seizures, accidents and suicide attempts respectively. 68% had own experience with drug-related emergency. A majority suffered opiate overdose with different extensions as unconsciousness or breath-depression. Alcohol and polydrug use was associated with overdose. Drug-related accidents were only reported by men. Half the number of drug-related emergencies were treated in hospital. Most emergencies occurred alone either in a home environment or outside. Harm reduction interventions like observed user rooms should be established. Furthermore other strategies to reduce the number of emergencies as sharing naloxon or resuscitation programs in wards for detoxification could also be an effective method to prevent near fatal or fatal overdoses in dependent subjects.

  16. Relative validity of the geisinger rural aging study food frequency questionniare

    Science.gov (United States)

    Objective: To determine the relative validity of a population specific food frequency questionnaire (FFQ) and evaluate the effectiveness of the instrument for assessing nutritional risk in older adults. Design: A cross-over design with participants completing two different dietary assessment inst...

  17. Clinical usefulness and feasibility of time-frequency analysis of chemosensory event-related potentials.

    Science.gov (United States)

    Huart, C; Rombaux, Ph; Hummel, T; Mouraux, A

    2013-09-01

    The clinical usefulness of olfactory event-related brain potentials (OERPs) to assess olfactory function is limited by the relatively low signal-to-noise ratio of the responses identified using conventional time-domain averaging. Recently, it was shown that time-frequency analysis of the obtained EEG signals can markedly improve the signal-to-noise ratio of OERPs in healthy controls, because it enhances both phase-locked and non phase-locked EEG responses. The aim of the present study was to investigate the clinical usefulness of this approach and evaluate its feasibility in a clinical setting. We retrospectively analysed EEG recordings obtained from 45 patients (15 anosmic, 15 hyposmic and 15 normos- mic). The responses to olfactory stimulation were analysed using conventional time-domain analysis and joint time-frequency analysis. The ability of the two methods to discriminate between anosmic, hyposmic and normosmic patients was assessed using a Receiver Operating Characteristic analysis. The discrimination performance of OERPs identified using conventional time-domain averaging was poor. In contrast, the discrimination performance of the EEG response identified in the time-frequency domain was relatively high. Furthermore, we found a significant correlation between the magnitude of this response and the psychophysical olfactory score. Time-frequency analysis of the EEG responses to olfactory stimulation could be used as an effective and reliable diagnostic tool for the objective clinical evaluation of olfactory function in patients.

  18. An exploration of preservice teachers’ educational values of mathematics in relation to gender and attitudes toward mathematics in Nigeria

    Directory of Open Access Journals (Sweden)

    Adeneye Olarewaju Awofala

    2018-04-01

    Full Text Available The study investigated educational values of mathematics in relation to gender and attitudes toward mathematics among 480 Nigerian preservice mathematics teachers from four universities in Southwest, Nigeria using the quantitative research method within the blueprint of the descriptive survey design. Data collected were analysed using the descriptive statistics of frequency, percentage, mean, and standard deviation and inferential statistics of independent samples t-test, Pearson moment correlation, and multiple regression analysis. Findings revealed that preservice mathematics teachers showed high level of educational value of mathematics. There were significant possible correlations among preservice mathematics teachers’ practical value, aesthetic value, cultural value, social value, moral value, disciplinary value, recreational value, and attitudes toward mathematics. While gender differences in some dimensions of educational value of mathematics (practical value, disciplinary value, social value, and cultural value are no longer important and are declining there are subtle gender differences in attitudes toward mathematics and educational values of mathematics in this study. In addition, 73.7% of the variance in preservice teachers’ attitudes toward mathematics was accounted for by the eight predictor variables (gender, practical or utilitarian value, disciplinary value, cultural value, social value, moral value, aesthetic value and recreational value taken together. Based on this baseline study, it was thus, recommended that future studies in Nigeria should investigate the educational value of mathematics of in-service teachers with varied ethnicity and socio-economic background so as to generalise the results of this study.

  19. Relative validation of the KiGGS Food Frequency Questionnaire among adolescents in Germany

    Directory of Open Access Journals (Sweden)

    Truthmann Julia

    2011-12-01

    Full Text Available Abstract Background The aim of this study was to determine the relative validity of the self-administered Food Frequency Questionnaire (FFQ "What do you eat?", which was used in the German National Health Interview and Examination Survey for Children and Adolescents (KiGGS 2003-2006. Methods The validation was conducted in the EsKiMo Nutrition Module, a subsample of KiGGS. The study population included 1,213 adolescents aged between 12 and 17. A modified diet history interview DISHES (Dietary Interview Software for Health Examination Studies was used as the reference method. In order to compare the food groups, the data assessed with both instruments were aggregated to 40 similar food groups. The statistical analysis included calculating and comparing Spearman's correlation coefficients, calculating the mean difference between both methods, and ranking participants (quartiles according to food group consumption, including weighted kappa coefficients. Correlations were also evaluated for relative body weight and socioeconomic status subgroups. Results In the total study population the Spearman correlation coefficients ranged from 0.22 for pasta/rice to 0.69 for margarine; most values were 0.50 and higher. The mean difference ranged between 1.4% for milk and 100.3% for pasta/rice. The 2.5 percentiles and 97.5 percentiles indicated a wide range of differences. Classifications in the same and adjacent quartile varied between 70.1% for pasta/rice and 90.8% for coffee. For most groups, Cohen's weighted kappa showed values between 0.21 and 0.60. Only for white bread and pasta/rice were values less than 0.20. Most of the 40 food groups showed acceptable to good correlations in all investigated subgroups concerning age, sex, body weight and socio-economic status. Conclusions The KiGGS FFQ showed fair to moderate ranking validity except for pasta/rice and white bread. However, the ability to assess absolute intakes is limited. The correlation coefficients

  20. Relative validation of the KiGGS Food Frequency Questionnaire among adolescents in Germany

    Science.gov (United States)

    2011-01-01

    Background The aim of this study was to determine the relative validity of the self-administered Food Frequency Questionnaire (FFQ) "What do you eat?", which was used in the German National Health Interview and Examination Survey for Children and Adolescents (KiGGS 2003-2006). Methods The validation was conducted in the EsKiMo Nutrition Module, a subsample of KiGGS. The study population included 1,213 adolescents aged between 12 and 17. A modified diet history interview DISHES (Dietary Interview Software for Health Examination Studies) was used as the reference method. In order to compare the food groups, the data assessed with both instruments were aggregated to 40 similar food groups. The statistical analysis included calculating and comparing Spearman's correlation coefficients, calculating the mean difference between both methods, and ranking participants (quartiles) according to food group consumption, including weighted kappa coefficients. Correlations were also evaluated for relative body weight and socioeconomic status subgroups. Results In the total study population the Spearman correlation coefficients ranged from 0.22 for pasta/rice to 0.69 for margarine; most values were 0.50 and higher. The mean difference ranged between 1.4% for milk and 100.3% for pasta/rice. The 2.5 percentiles and 97.5 percentiles indicated a wide range of differences. Classifications in the same and adjacent quartile varied between 70.1% for pasta/rice and 90.8% for coffee. For most groups, Cohen's weighted kappa showed values between 0.21 and 0.60. Only for white bread and pasta/rice were values less than 0.20. Most of the 40 food groups showed acceptable to good correlations in all investigated subgroups concerning age, sex, body weight and socio-economic status. Conclusions The KiGGS FFQ showed fair to moderate ranking validity except for pasta/rice and white bread. However, the ability to assess absolute intakes is limited. The correlation coefficients for most food items were

  1. Hazard analysis of typhoon-related external events using extreme value theory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yo Chan; Jang, Seung Cheol [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lim, Tae Jin [Dept. of Industrial Information Systems Engineering, Soongsil University, Seoul (Korea, Republic of)

    2015-02-15

    After the Fukushima accident, the importance of hazard analysis for extreme external events was raised. To analyze typhoon-induced hazards, which are one of the significant disasters of East Asian countries, a statistical analysis using the extreme value theory, which is a method for estimating the annual exceedance frequency of a rare event, was conducted for an estimation of the occurrence intervals or hazard levels. For the four meteorological variables, maximum wind speed, instantaneous wind speed, hourly precipitation, and daily precipitation, the parameters of the predictive extreme value theory models were estimated. The 100-year return levels for each variable were predicted using the developed models and compared with previously reported values. It was also found that there exist significant long-term climate changes of wind speed and precipitation. A fragility analysis should be conducted to ensure the safety levels of a nuclear power plant for high levels of wind speed and precipitation, which exceed the results of a previous analysis.

  2. Single and multi-frequency impedance characterization of symmetric activated carbon single capacitor cells

    Directory of Open Access Journals (Sweden)

    Suzana Sopčić

    2018-05-01

    Full Text Available Electrochemical impedance spectroscopy (EIS technique is used for characterization of single cell symmetric capacitors having different mass loadings of activated carbon (AC. Relevant values of charge storage capacitance (CT and internal resistance (ESR were evaluated by the single frequency and multi-frequency analyses of measured impedance spectra. Curve fittings were based on the non-ideal R-C model that takes into account the parasitic inductance, contributions from electrode materials/contacts and the effects of AC porosity. Higher CT and lower ESR values were obtained not only for the cell with higher mass of AC, but also using the single vs. multi-frequency approach. Lower CT and higher values of ESR that are generally obtained using the multi-frequency method and curve fittings should be related to the not ideal capacitive response of porous AC material and too high frequency chosen in applying the single frequency analysis.

  3. Changes in time and frequency related aspects of motor unit action potentials during fatigue

    NARCIS (Netherlands)

    Wallinga, W.; Bouwens, Jeroen S.; Baten, Christian T.M.

    1996-01-01

    During fatigue the shape of motor unit action potentials (MUAPs) change. Characteristics of the MUAPs described before concern several time related aspects. No attention has been given to the frequency spectrum changes of MUAPS. The median frequency of MUAPS has now been determined for motor units

  4. Understanding News Values: Secret to Good Public Relations.

    Science.gov (United States)

    Oates, Rita Haugh

    1981-01-01

    Explains the news values that journalists use. Shows English teachers and administrators how they can apply this knowledge of news media to improve public relations between the school and the community. (RL)

  5. Exploring intrinsic, instrumental, and relational values for sustainable management of social-ecological systems

    Directory of Open Access Journals (Sweden)

    Paola Arias-Arévalo

    2017-12-01

    Full Text Available The values (i.e., importance that people place on ecosystems have been identified as a crucial dimension of sustainable management of social-ecological systems. Recently, the call for integrating plural values of ecosystems beyond intrinsic and instrumental values has prompted the notion of "relational values." With the aim of contributing to environmental management, we assess the environmental motivations (i.e., egoistic, biospheric, altruistic and values that people attribute to the ecosystems of the mid-upper stream of the Otún River watershed, central Andes, Colombia. We analyzed 589 questionnaires that were collected in urban and rural areas of the Otún River watershed using the nonparametric Mann-Whitney U test and logistic regressions. We found salient biospheric motivations and the attribution of plural values (i.e., intrinsic, relational, and instrumental to the ecosystems of the mid-upper stream of the Otún River watershed. Particularly, relational values were the most frequently mentioned value domain. Further, our results showed that environmental motivations and socioeconomic factors are associated with the expression of different value domains. We found negative associations between egoistic motivations and intrinsic values and between rural respondents and instrumental values. We found positive associations between altruistic motivations and relational values and between rural respondents and both intrinsic and relational values. In light of our results, we argue that intrinsic, instrumental, and relational values coexist in people's narratives about the importance of ecosystems. Plural valuation approaches could be enhanced by differentiating relational from instrumental values and by expressing them in nonmonetary terms. We argue that multiple values of ecosystems expressed by rural and urban societies should be included in environmental management to tackle social conflicts and consider the diverse needs and interests of

  6. Variable frequency iteration MPPT for resonant power converters

    Science.gov (United States)

    Zhang, Qian; Bataresh, Issa; Chen, Lin

    2015-06-30

    A method of maximum power point tracking (MPPT) uses an MPPT algorithm to determine a switching frequency for a resonant power converter, including initializing by setting an initial boundary frequency range that is divided into initial frequency sub-ranges bounded by initial frequencies including an initial center frequency and first and second initial bounding frequencies. A first iteration includes measuring initial powers at the initial frequencies to determine a maximum power initial frequency that is used to set a first reduced frequency search range centered or bounded by the maximum power initial frequency including at least a first additional bounding frequency. A second iteration includes calculating first and second center frequencies by averaging adjacent frequent values in the first reduced frequency search range and measuring second power values at the first and second center frequencies. The switching frequency is determined from measured power values including the second power values.

  7. Good neighbourly relations or family values?

    DEFF Research Database (Denmark)

    McQuaid, Sara Dybris

    Good neighbourly relations or family values? Assessing British Irish cooperation in a comparative perspective 1990-2010. This paper forms part of a larger comparative study, which charts the past 20 years development of British Irish cooperation and Nordic cooperation. It examines specifically...... associations lies in the legitimacy they derive from a historical narrative of a common social, cultural, economic and political fabric. Importantly, however, the impetus behind the cooperation is constructed from both associative and ascriptive components of collective identity; cooperation is motivated...

  8. Initiating events frequency determination

    International Nuclear Information System (INIS)

    Simic, Z.; Mikulicic, V.; Vukovic, I.

    2004-01-01

    The paper describes work performed for the Nuclear Power Station (NPS). Work is related to the periodic initiating events frequency update for the Probabilistic Safety Assessment (PSA). Data for all relevant NPS initiating events (IE) were reviewed. The main focus was on events occurring during most recent operating history (i.e., last four years). The final IE frequencies were estimated by incorporating both NPS experience and nuclear industry experience. Each event was categorized according to NPS individual plant examination (IPE) initiating events grouping approach. For the majority of the IE groups, few, or no events have occurred at the NPS. For those IE groups with few or no NPS events, the final estimate was made by means of a Bayesian update with general nuclear industry values. Exceptions are rare loss-of-coolant-accidents (LOCA) events, where evaluation of engineering aspects is used in order to determine frequency.(author)

  9. Investigation of Frequency of Leftover Drugs at Home and Related Factors

    Directory of Open Access Journals (Sweden)

    Muharrem Ucar

    2009-04-01

    Full Text Available AIM: The purpose of this survey was to investigate the frequency of leftover drugs at homes and related factors regarding this problem. METHOD: This descriptive study was performed among 692 non-medical personnel servicing at two military bases in December 2006. Data were collected by using a questionnaire, which had been developed by the investigators. Frequencies and percents were used as descriptive statistics. Chi-square test was used to compare the frequencies of leftover drugs according to certain variables. RESULTS: Of the total participants 78,8% were males, 72,8% aged between 18 to 39, and 29,6% were unmarried. The findings revealed that 61,3% of the participants had leftover drugs at their homes. Participants living with together 2 to 4 family members had higher frequencies of leftover drugs at homes. When we looked at the frequencies of leftover drugs according to drug use behaviors; the frequency of leftover drug was determined higher among those who stated; the recipe was not explained sufficiently, he did not use drugs as directed, he kept drugs until due time when did not use all of the drugs, he kept drugs in a box or bag, he visited a health center in order to have a recipe (p<0,05. CONCLUSION: It was determined leftover drugs were kept at nearly two third of the participants’ homes. Regarding incompleteness of treatment, the intoxication risk for children, and drug waste, this frequency of drug leftover was high, and all responsible professions in the chain of rationale drug use particularly physicians should be awaked on this issue. The use of drugs in a recipe should be explained to patients clearly. [TAF Prev Med Bull 2009; 8(2.000: 113-118

  10. The Relative Frequency of Persistent Hyperthyroidism After I131Therapy

    International Nuclear Information System (INIS)

    Al-EID, M.A.

    1998-01-01

    517 patients with different types of hyperthyroidism who had treated by I 131 therapy were studied. The study demonstrated that diffuse toxic goiter was the most common type of hyperthyroidism. The relative frequency of persistent hyperthyroidism in all types after the first dose of I 131 utilizing our empirical regimen in estimation of therapy doses was low (9.5%). While high frequency of persistent hyperthyroidism among diffuse toxic goiter patients (14%), probably was due to many factors discussed in this paper. Some of these factors are impossible to be estimated precisely and therefore, can not be avoided. But careful dose estimation for each case with diffuse toxic goiter may reduce the rate of retreatment by I 131 . Antithyroid medication prior to I 131 therapy might be another factor resulted in increasing of retreatment of retreatment rate diffuse toxic goiter cases. Longer time interval (more than 5 days) of ceasing antithyroid medication prior therapy is suggested to avoid the effects of these drugs. Patients with other types of hyperthyroidism were not frequently required more than one dose and the frequency of persistent hyperthyroidism was almost negligible

  11. Generating an AC amplitude magnetic flux density value up to 150 μT at a frequency up to 100 kHz

    Science.gov (United States)

    Ulvr, Michal; Polonský, Jakub

    2017-05-01

    AC magnetic field analyzers with a triaxial coil probe are widely used by health and safety professionals, in manufacturing, and in service industries. For traceable calibration of these analyzers, it is important to be able to generate a stable, homogeneous reference AC magnetic flux density (MFD). In this paper, the generating of AC amplitude MFD value of 150 μT by single-layer Helmholtz type solenoid, described in previous work, was expanded up to a frequency of 100 kHz using the effect of serial resonance. A programmable capacitor array has been developed with a range of adjustable values from 50 pF to 51225 pF. In addition, the multi-layer search coil with a nominal area turns value of 1.3m2, used for adjusting AC MFD in the solenoid, has been modified by a transimpedance amplifier for use in a wider frequency range than up to 3 kHz. The possibility of using the programmable capacitor array up to 150 kHz has also been tested. An AC amplitude MFD value of 150 μT can be generated with expanded uncertainty better than 0.6% up to 100 kHz.

  12. THE RELATION OF FREQUENCY TO THE PHYSIOLOGICAL EFFECTS OF ULTRA-HIGH FREQUENCY CURRENTS.

    Science.gov (United States)

    Christie, R V; Loomis, A L

    1929-01-31

    1. Biological effects of electromagnetic waves emitted by a vacuum tube oscillator have been studied at frequencis ranging from 8,300,000 to 158,000,000 cycles per second (1.9 to 38 meters wave-length). 2. The effects produced on animals can be fully explained on the basis of the heat generated by high frequency currents which are induced in them. 3. No evidence was obtained to support the theory that certain wave-lengths have a specific action on living cells. 4. At frequencies below 50,000,000 cycles, the effect of these radiations on animals is proportionate to the intensity of the electro-magnetic field. As the frequency is increased beyond this point, the amount of induced current is diminished and the apparent lethality of the radiation is decreased. This can be explained by changes occurring in the dielectric properties of tissues at low wave-lengths.

  13. Human dignity: intrinsic or relative value?

    Science.gov (United States)

    Thiel, Marie-Jo

    2010-09-01

    Is human dignity an intrinsic value? Or is it a relative value, depending on the perception or assessment of quality of life? History had delineated some of its key features, but the advent of human rights and the Holocaust put special emphasis on this notion, particularly in the field of bioethics. But if modern medicine regards human dignity as crucial, it tends to support this notion while assessing and measuring it. The quality of life becomes the gauge for measuring human dignity, starting from a distinction between a viable and a non-viable existence, which may eventually lead to assisted death, or to letting die. This article argues that the concept of quality of life is of great relevant for medical practice, but on the condition of not being used as a standard to measure the dignity of the individual. Rather, the quality of life should be regarded as an imperative posed by human dignity, which is necessarily intrinsic. If the quality of life measures dignity, humankind is divided into two categories: lives worthy of living, and lives unworthy of living, and society becomes a jungle. Raising the quality of life as a requirement of the inherent human dignity does not solve automatically all problems and does not eliminate a feeling of unworthiness. But it ensures its 'human' value: the equal respect for every human being.

  14. A Percolation Perspective for Gutenburg-Richter Scaling and b-values for Fracking Assocated Seismicity

    Science.gov (United States)

    Norris, J. Q.

    2016-12-01

    Published 60 years ago, the Gutenburg-Richter law provides a universal frequency-magnitude distribution for natural and induced seismicity. The GR law is a two parameter power-law with the b-value specifying the relative frequency of small and large events. For large catalogs of natural seismicity, the observed b-values are near one, while fracking associated seismicity has observed b-values near two, indicating relatively fewer large events. We have developed a computationally inexpensive percolation model for fracking that allows us to generate large catalogs of fracking associated seismicity. Using these catalogs, we show that different power-law fitting procedures produce different b-values for the same data set. This shows that care must be taken when determining and comparing b-values for fracking associated seismicity.

  15. Effects of Sound Frequency on Audiovisual Integration: An Event-Related Potential Study.

    Science.gov (United States)

    Yang, Weiping; Yang, Jingjing; Gao, Yulin; Tang, Xiaoyu; Ren, Yanna; Takahashi, Satoshi; Wu, Jinglong

    2015-01-01

    A combination of signals across modalities can facilitate sensory perception. The audiovisual facilitative effect strongly depends on the features of the stimulus. Here, we investigated how sound frequency, which is one of basic features of an auditory signal, modulates audiovisual integration. In this study, the task of the participant was to respond to a visual target stimulus by pressing a key while ignoring auditory stimuli, comprising of tones of different frequencies (0.5, 1, 2.5 and 5 kHz). A significant facilitation of reaction times was obtained following audiovisual stimulation, irrespective of whether the task-irrelevant sounds were low or high frequency. Using event-related potential (ERP), audiovisual integration was found over the occipital area for 0.5 kHz auditory stimuli from 190-210 ms, for 1 kHz stimuli from 170-200 ms, for 2.5 kHz stimuli from 140-200 ms, 5 kHz stimuli from 100-200 ms. These findings suggest that a higher frequency sound signal paired with visual stimuli might be early processed or integrated despite the auditory stimuli being task-irrelevant information. Furthermore, audiovisual integration in late latency (300-340 ms) ERPs with fronto-central topography was found for auditory stimuli of lower frequencies (0.5, 1 and 2.5 kHz). Our results confirmed that audiovisual integration is affected by the frequency of an auditory stimulus. Taken together, the neurophysiological results provide unique insight into how the brain processes a multisensory visual signal and auditory stimuli of different frequencies.

  16. The frequency of company-sponsored alcohol brand-related sites on Facebook™-2012.

    Science.gov (United States)

    Nhean, Siphannay; Nyborn, Justin; Hinchey, Danielle; Valerio, Heather; Kinzel, Kathryn; Siegel, Michael; Jernigan, David H

    2014-06-01

    This research provides an estimate of the frequency of company-sponsored alcohol brand-related sites on Facebook™. We conducted a systematic overview of the extent of alcohol brand-related sites on Facebook™ in 2012. We conducted a 2012 Facebook™ search for sites specifically related to 898 alcohol brands across 16 different alcoholic beverage types. Descriptive statistics were produced using Microsoft SQL Server. We identified 1,017 company-sponsored alcohol-brand related sites on Facebook™. Our study advances previous literature by providing a systematic overview of the extent of alcohol brand sites on Facebook™.

  17. The frequency of involuntary autobiographical memories and future thoughts in relation to daydreaming, emotional distress, and age.

    Science.gov (United States)

    Berntsen, Dorthe; Rubin, David C; Salgado, Sinue

    2015-11-01

    We introduce a new scale, the Involuntary Autobiographical Memory Inventory (IAMI), for measuring the frequency of involuntary autobiographical memories and involuntary future thoughts. Using the scale in relation to other psychometric and demographic measures provided three important, novel findings. First, the frequency of involuntary and voluntary memories and future thoughts are similarly related to general measures of emotional distress. This challenges the idea that the involuntary mode is uniquely associated with emotional distress. Second, the frequency of involuntary autobiographical remembering does not decline with age, whereas measures of daydreaming, suppression of unwanted thoughts and dissociative experiences all do. Thus, involuntary autobiographical remembering relates differently to aging than daydreaming and other forms of spontaneous and uncontrollable thoughts. Third, unlike involuntary autobiographical remembering, the frequency of future thoughts does decrease with age. This finding underscores the need for examining past and future mental time travel in relation to aging and life span development. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Daily meal frequency and associated variables in children and adolescents

    Directory of Open Access Journals (Sweden)

    Fabiana A. Silva

    2017-01-01

    Conclusion: Lower frequency of meals was related to lower income in children and adolescents, larger number of sons in the family, and increased values of body mass index and low‐density lipoprotein.

  19. The relative frequency of common neuromuscular diagnoses in a reference center.

    Science.gov (United States)

    Cotta, Ana; Paim, Júlia Filardi; Carvalho, Elmano; da-Cunha-Júnior, Antonio Lopes; Navarro, Monica M; Valicek, Jaquelin; Menezes, Miriam Melo; Nunes, Simone Vilela; Xavier-Neto, Rafael; Baptista, Sidney; Lima, Luciano Romero; Takata, Reinaldo Issao; Vargas, Antonio Pedro

    2017-11-01

    The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. To report the relative frequency of common neuromuscular diagnoses in a reference center. A 17-year chart review of patients with suspicion of myopathy. Among 3,412 examinations, 1,603 (46.98%) yielded confirmatory results: 782 (48.78%) underwent molecular studies, and 821 (51.21%) had muscle biopsies. The most frequent diagnoses were: dystrophinopathy 460 (28.70%), mitochondriopathy 330 (20.59%), spinal muscular atrophy 158 (9.86%), limb girdle muscular dystrophy 157 (9.79%), Steinert myotonic dystrophy 138 (8.61%), facioscapulohumeral muscular dystrophy 99 (6.17%), and other diagnoses 261 (16.28%). Using the presently-available diagnostic techniques in this service, a specific limb girdle muscular dystrophy subtype diagnosis was reached in 61% of the patients. A neuromuscular-appropriate diagnosis is important for genetic counseling, rehabilitation orientation, and early treatment of respiratory and cardiac complications.

  20. The relative frequency of common neuromuscular diagnoses in a reference center

    Directory of Open Access Journals (Sweden)

    Ana Cotta

    Full Text Available ABSTRACT The diagnostic procedure in neuromuscular patients is complex. Knowledge of the relative frequency of neuromuscular diseases within the investigated population is important to allow the neurologist to perform the most appropriate diagnostic tests. Objective: To report the relative frequency of common neuromuscular diagnoses in a reference center. Methods: A 17-year chart review of patients with suspicion of myopathy. Results: Among 3,412 examinations, 1,603 (46.98% yielded confirmatory results: 782 (48.78% underwent molecular studies, and 821 (51.21% had muscle biopsies. The most frequent diagnoses were: dystrophinopathy 460 (28.70%, mitochondriopathy 330 (20.59%, spinal muscular atrophy 158 (9.86%, limb girdle muscular dystrophy 157 (9.79%, Steinert myotonic dystrophy 138 (8.61%, facioscapulohumeral muscular dystrophy 99 (6.17%, and other diagnoses 261 (16.28%. Conclusion: Using the presently-available diagnostic techniques in this service, a specific limb girdle muscular dystrophy subtype diagnosis was reached in 61% of the patients. A neuromuscular-appropriate diagnosis is important for genetic counseling, rehabilitation orientation, and early treatment of respiratory and cardiac complications.

  1. Joint time-frequency analysis of ultrasonic signal

    International Nuclear Information System (INIS)

    Oh, Sae Kyu; Nam, Ki Woo; Oh, Jung Hwan; Lee, Keun Chan; Jang, Hong Keun

    1998-01-01

    This paper examines the propagation of Lamb (or plate) waves in anisotropic laminated composite plates. The dispersion relations are explicitly derived using the classical plate theory (CLT), the first-order shear deformation theory (FSDT) and the exact solution (ES), Attention is paid to the lowest antisymmetric (flexural) and lowest symmetric(extensional) modes in the low frequency, long wavelength limit. Different values of shear correction factor were tested in FSDT and comparisons between flexural wave dispersion curves were made with exact results to asses the range of validity of approximate plate theories in the frequency domain.

  2. The frequency and severity of metabolic acidosis related to topiramate.

    Science.gov (United States)

    Türe, Hatice; Keskin, Özgül; Çakır, Ülkem; Aykut Bingöl, Canan; Türe, Uğur

    2016-12-01

    Objective We planned a cross-sectional analysis to determine the frequency and severity of metabolic acidosis in patients taking topiramate while awaiting craniotomy. Methods Eighty patients (18 - 65 years) taking topiramate to control seizures while awaiting elective craniotomy were enrolled. Any signs of metabolic acidosis or topiramate-related side effects were investigated. Blood chemistry levels and arterial blood gases, including lactate, were obtained. The severity of metabolic acidosis was defined according to base excess levels as mild or moderate. Results Blood gas analysis showed that 71% ( n = 57) of patients had metabolic acidosis. The frequency of moderate metabolic acidosis was 56% ( n = 45), while that of mild metabolic acidosis was 15% ( n = 12). A high respiratory rate was reported in only 10% of moderately acidotic patients. Conclusions In patients receiving topiramate, baseline blood gas analysis should be performed preoperatively to determine the presence and severity of metabolic acidosis.

  3. Fruit and vegetable consumption and food values: National patterns in the United States by Supplemental Nutrition Assistance Program eligibility and cooking frequency.

    Science.gov (United States)

    Wolfson, Julia A; Bleich, Sara N

    2015-07-01

    More frequent cooking at home may help improve diet quality and be associated with food values, particularly for individuals participating in the Supplemental Nutrition Assistance Program (SNAP). To examine patterns of fruit and vegetable consumption and food values among adults (aged 20 and older) in the United States, by SNAP participation and household cooking frequency. Analysis of cross-sectional 24-hour dietary recall data obtained from the National Health and Nutrition Examination Survey 2007-2010 (N=9560). A lower percentage of SNAP participants consumed fruit (total: 35% vs. 46%, p=0.001; fresh: 30% vs. 41%, pcooking >6times/week was associated with greater vegetable consumption compared to cooking cooked ≥2times/week were more to report price (medium cookers: 47% vs. 33%, p=0.001; high cookers: 52% vs. 40%, pcooking frequency. Efforts to improve diet quality should consider values on which food purchases are based. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Genetic frequencies related to severe or profound sensorineural hearing loss in Inner Mongolia Autonomous Region

    Directory of Open Access Journals (Sweden)

    Yongzhi Liu

    Full Text Available Abstract The aim was to study the frequencies of common deafness-related mutations and their contribution to hearing loss in different regions of Inner Mongolia. A total of 738 deaf children were recruited from five different ethnic groups of Inner Mongolia, including Han Chinese (n=486, Mongolian (n=216, Manchurian (n=24, Hui (n=6 and Daur (n=6. Nine common mutations in four genes (GJB2, SLC26A4, GJB3 and mitochondrial MT-RNR1 gene were detected by allele-specific PCR and universal array. At least one mutated allele was detected in 282 patients. Pathogenic mutations were detected in 168 patients: 114 were homozygotes and 54 were compound heterozygotes. The 114 patients were carriers of only one mutated allele. The frequency of GJB2 variants in Han Chinese (21.0% was higher than that in Mongolians (16.7%, but not significantly different. On the other hand, the frequency of SLC26A4 variants in Han Chinese (14.8% was lower than that in Mongolians (19.4%, but also not significantly different. The frequency of patients with pathogenic mutations was different in Ulanqab (21.4%, Xilingol (40.0%, Chifeng (40.0%, Hulunbeier (30.0%, Hohhot (26.3%, and in Baotou (0%. In conclusion, the frequency of mutated alleles in deafness-related genes did not differ between Han Chinese and Mongolians. However, differences in the distribution of common deafness-related mutations were found among the investigated areas of Inner Mongolia.

  5. Variation of b and p values from aftershocks sequences along the Mexican subduction zone and their relation to plate characteristics

    Science.gov (United States)

    Ávila-Barrientos, L.; Zúñiga, F. R.; Rodríguez-Pérez, Q.; Guzmán-Speziale, M.

    2015-11-01

    Aftershock sequences along the Mexican subduction margin (between coordinates 110ºW and 91ºW) were analyzed by means of the p value from the Omori-Utsu relation and the b value from the Gutenberg-Richter relation. We focused on recent medium to large (Mw > 5.6) events considered susceptible of generating aftershock sequences suitable for analysis. The main goal was to try to find a possible correlation between aftershock parameters and plate characteristics, such as displacement rate, age and segmentation. The subduction regime of Mexico is one of the most active regions of the world with a high frequency of occurrence of medium to large events and plate characteristics change along the subduction margin. Previous studies have observed differences in seismic source characteristics at the subduction regime, which may indicate a difference in rheology and possible segmentation. The results of the analysis of the aftershock sequences indicate a slight tendency for p values to decrease from west to east with increasing of plate age although a statistical significance is undermined by the small number of aftershocks in the sequences, a particular feature distinctive of the region as compared to other world subduction regimes. The b values show an opposite, increasing trend towards the east even though the statistical significance is not enough to warrant the validation of such a trend. A linear regression between both parameters provides additional support for the inverse relation. Moreover, we calculated the seismic coupling coefficient, showing a direct relation with the p and b values. While we cannot undoubtedly confirm the hypothesis that aftershock generation depends on certain tectonic characteristics (age, thickness, temperature), our results do not reject it thus encouraging further study into this question.

  6. An analysis of the relation between employee-organization value congruence and employee attitudes.

    Science.gov (United States)

    Amos, Elizabeth A; Weathington, Bart L

    2008-11-01

    Researchers have examined the fit or match between a person and an organization extensively in the empirical literature. Overall findings have supported the existence of a positive relation between the congruence of employee and organizational values with employee attitudes toward the organization. However, this relation is not fully understood, and more research is needed to understand the relation between the congruence of different value dimensions and multiple employee attitudes. Therefore, the authors aimed to analyze value congruence across 7 dimensions and its relation to (a) job satisfaction, (b) organizational commitment, (c) satisfaction with the organization as a whole, and (d) turnover intentions. The results suggest that the perceived congruence of employee-organizational values by employees is positively associated with satisfaction with the job and organization as a whole and employee commitment to the organization. The results also support a negative relation between value congruence and employee turnover intentions.

  7. Meal frequency in relation to prevalence of functional dyspepsia among Iranian adults.

    Science.gov (United States)

    Hassanzadeh, Shakiba; Saneei, Parvane; Keshteli, Ammar Hassanzadeh; Daghaghzadeh, Hamed; Esmaillzadeh, Ahmad; Adibi, Peyman

    2016-02-01

    Limited data are available linking diet-related practices to functional dyspepsia (FD). The aim of this study was to investigate the association between meal frequency and prevalence of FD among a large sample of Iranian adults. In this cross-sectional study, 4763 individuals from the general adult population in Isfahan were asked to report on how many main meals and snacks they consumed each day. Frequency of total meals was defined by summing up the frequency of main meals and snacks. Participants were grouped into four categories: less than three, three to five, six to seven, and eight or more meals daily. FD symptoms were assessed using a validated Persian version of the Rome III questionnaire, and FD was defined as bothersome postprandial fullness, early satiation, and/or epigastric pain or epigastric burning. Compared with individuals who had one main meal per day, those who consumed three main meals daily had a lower chance for early satiation (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.21-0.90). Findings from the analysis on snack frequency revealed that, compared with those who never consumed snacks, individuals who consumed three to five snacks daily were 39% less likely to have FD (OR, 0.61; 95% CI, 0.40-0.92), had 42% lower odds of postprandial fullness (OR, 0.58; 95% CI, 0.34-0.98), and were at 43% lower risk for epigastric pain (OR, 0.57; 95% CI, 0.34-0.97). After adjustment for potential confounders, including diet-related behaviors, individuals who consumed six to seven total meals and snacks per day had lower odds of FD (OR, 0.51; 95% CI, 0.31-0.82) compared with those with who ate fewer than three meals and snacks daily. A similar inverse association was seen between meal and snack frequency and early satiation (OR, 0.32; 95% CI, 0.16-0.63) and postprandial fullness (OR, 0.54; 95% CI, 0.29-0.98). Results from the present study demonstrated an inverse association between meal and snack frequency and prevalence of FD and its components

  8. A Relational Account of Call-by-Value Sequentiality

    DEFF Research Database (Denmark)

    Riecke, Jon Gary; Sandholm, Anders Bo

    2002-01-01

    We construct a model for FPC, a purely functional, sequential, call-by-value language. The model is built from partial continuous functions, in the style of Plotkin, further constrained to be uniform with respect to a class of logical relations. We prove that the model is fully abstract....

  9. LOFAR/H-ATLAS: the low-frequency radio luminosity-star formation rate relation

    Science.gov (United States)

    Gürkan, G.; Hardcastle, M. J.; Smith, D. J. B.; Best, P. N.; Bourne, N.; Calistro-Rivera, G.; Heald, G.; Jarvis, M. J.; Prandoni, I.; Röttgering, H. J. A.; Sabater, J.; Shimwell, T.; Tasse, C.; Williams, W. L.

    2018-04-01

    Radio emission is a key indicator of star formation activity in galaxies, but the radio luminosity-star formation relation has to date been studied almost exclusively at frequencies of 1.4 GHz or above. At lower radio frequencies, the effects of thermal radio emission are greatly reduced, and so we would expect the radio emission observed to be completely dominated by synchrotron radiation from supernova-generated cosmic rays. As part of the LOFAR Surveys Key Science project, the Herschel-ATLAS NGP field has been surveyed with LOFAR at an effective frequency of 150 MHz. We select a sample from the MPA-JHU catalogue of Sloan Digital Sky Survey galaxies in this area: the combination of Herschel, optical and mid-infrared data enable us to derive star formation rates (SFRs) for our sources using spectral energy distribution fitting, allowing a detailed study of the low-frequency radio luminosity-star formation relation in the nearby Universe. For those objects selected as star-forming galaxies (SFGs) using optical emission line diagnostics, we find a tight relationship between the 150 MHz radio luminosity (L150) and SFR. Interestingly, we find that a single power-law relationship between L150 and SFR is not a good description of all SFGs: a broken power-law model provides a better fit. This may indicate an additional mechanism for the generation of radio-emitting cosmic rays. Also, at given SFR, the radio luminosity depends on the stellar mass of the galaxy. Objects that were not classified as SFGs have higher 150-MHz radio luminosity than would be expected given their SFR, implying an important role for low-level active galactic nucleus activity.

  10. Broadcast Communication by System Frequency Modulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; You, Shi; Heussen, Kai

    2012-01-01

    Load controllers available today can measure AC system frequency and react to frequency deviations. A system operator can communicate to frequency sensitive loads by changing the set-points of the system’s dispatchable frequency regulation resources. Explicitly signaling system state by generating...... off-nominal system frequency values is a novel narrowband broadcast communications channel between system operators and frequency sensitive distributed energy resources (FS-DER). The feasibility of the proposed system is evaluated on an existing island power system in Denmark. This study shows...... that within standard frequency quality constraints, 4 distinct symbols are feasible on the island. However, the overarching imperative of system stability prevents the symbols from having arbitrary meanings. Higher frequency values must translate into greater consumption from loads, and vice versa. Within...

  11. Neural correlates of economic value and valuation context: an event-related potential study.

    Science.gov (United States)

    Tyson-Carr, John; Kokmotou, Katerina; Soto, Vicente; Cook, Stephanie; Fallon, Nicholas; Giesbrecht, Timo; Stancak, Andrej

    2018-05-01

    The value of environmental cues and internal states is continuously evaluated by the human brain, and it is this subjective value that largely guides decision making. The present study aimed to investigate the initial value attribution process, specifically the spatiotemporal activation patterns associated with values and valuation context, using electroencephalographic event-related potentials (ERPs). Participants completed a stimulus rating task in which everyday household items marketed up to a price of £4 were evaluated with respect to their desirability or material properties. The subjective values of items were evaluated as willingness to pay (WTP) in a Becker-DeGroot-Marschak auction. On the basis of the individual's subjective WTP values, the stimuli were divided into high- and low-value items. Source dipole modeling was applied to estimate the cortical sources underlying ERP components modulated by subjective values (high vs. low WTP) and the evaluation condition (value-relevant vs. value-irrelevant judgments). Low-WTP items and value-relevant judgments both led to a more pronounced N2 visual evoked potential at right frontal scalp electrodes. Source activity in right anterior insula and left orbitofrontal cortex was larger for low vs. high WTP at ∼200 ms. At a similar latency, source activity in right anterior insula and right parahippocampal gyrus was larger for value-relevant vs. value-irrelevant judgments. A stronger response for low- than high-value items in anterior insula and orbitofrontal cortex appears to reflect aversion to low-valued item acquisition, which in an auction experiment would be perceived as a relative loss. This initial low-value bias occurs automatically irrespective of the valuation context. NEW & NOTEWORTHY We demonstrate the spatiotemporal characteristics of the brain valuation process using event-related potentials and willingness to pay as a measure of subjective value. The N2 component resolves values of objects with a

  12. Comparative analysis of internal friction and natural frequency measured by free decay and forced vibration

    International Nuclear Information System (INIS)

    Wang, Y. Z.; Ding, X. D.; Xiong, X. M.; Zhang, J. X.

    2007-01-01

    Relations between various values of the internal friction (tgδ, Q -1 , Q -1* , and Λ/π) measured by free decay and forced vibration are analyzed systemically based on a fundamental mechanical model in this paper. Additionally, relations between various natural frequencies, such as vibration frequency of free decay ω FD , displacement-resonant frequency of forced vibration ω d , and velocity-resonant frequency of forced vibration ω 0 are calculated. Moreover, measurement of natural frequencies of a copper specimen of 99.9% purity has been made to demonstrate the relation between the measured natural frequencies of the system by forced vibration and free decay. These results are of importance for not only more accurate measurement of the elastic modulus of materials but also the data conversion between different internal friction measurements

  13. Value-impact assessment of safety-related modifications

    International Nuclear Information System (INIS)

    Knowles, W.M.C.; Dinnie, K.S.; Gordon, C.W.

    1992-01-01

    Like other nuclear utilities, Ontario Hydro, as part of its risk management activities, continually assesses the safety of its nuclear operations. In addition, new regulatory requirements are being applied to the older nuclear power plants. Both of these result in proposed plant modifications designed to reduce the risk to the public. However, modifications to an operating plant can have serious economic effects, and the resources, both financial and personnel, required for the implementation of these modifications are limited. Thus, all potential benefits and effects of a proposed modification must be thoroughly investigated to judge whether the modification is beneficial. Ontario Hydro has begun to use comprehensive value-impact assessments, utilizing plant-specific probabilistic risk assessments (PRAs), as tools to provide an informed basis for judgments on the benefit of safety-related modifications. The results from value-impact assessments can also be used to prioritize the implementation of these modifications

  14. Math-related career aspirations and choices within Eccles et al.'s expectancy-value theory of achievement-related behaviors.

    Science.gov (United States)

    Lauermann, Fani; Tsai, Yi-Miau; Eccles, Jacquelynne S

    2017-08-01

    Which occupation to pursue is one of the more consequential decisions people make and represents a key developmental task. Yet the underlying developmental processes associated with either individual or group differences in occupational choices are still not well understood. This study contributes toward filling this gap, focusing in particular on the math domain. We examined two aspects of Eccles et al.'s (1983) expectancy-value theory of achievement-related behaviors: (a) the reciprocal associations between adolescents' expectancy and subjective task value beliefs and adolescents' career plans and (b) the multiplicative association between expectancies and values in predicting occupational outcomes in the math domain. Our analyses indicate that adolescents' expectancy and subjective task value beliefs about math and their math- or science-related career plans reported at the beginning and end of high school predict each other over time, with the exception of intrinsic interest in math. Furthermore, multiplicative associations between adolescents' expectancy and subjective task value beliefs about math predict math-related career attainment approximately 15 years after graduation from high school. Gender differences emerged regarding career-related beliefs and career attainment, with male students being more likely than female to both pursue and attain math-related careers. These gender differences could not be explained by differences in beliefs about math as an academic subject. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Estimating return periods of extreme values from relatively short time series of winds

    Science.gov (United States)

    Jonasson, Kristjan; Agustsson, Halfdan; Rognvaldsson, Olafur; Arfeuille, Gilles

    2013-04-01

    An important factor for determining the prospect of individual wind farm sites is the frequency of extreme winds at hub height. Here, extreme winds are defined as the value of the highest 10 minutes averaged wind speed with a 50 year return period, i.e. annual exceeding probability of 2% (Rodrigo, 2010). A frequently applied method to estimate winds in the lowest few hundred meters above ground is to extrapolate observed 10-meter winds logarithmically to higher altitudes. Recent study by Drechsel et al. (2012) showed however that this methodology is not as accurate as interpolating simulated results from the global ECMWF numerical weather prediction (NWP) model to the desired height. Observations of persistent low level jets near Colima in SW-Mexico also show that the logarithmic approach can give highly inaccurate results for some regions (Arfeuille et al., 2012). To address these shortcomings of limited, and/or poorly representative, observations and extrapolations of winds one can use NWP models to dynamically scale down relatively coarse resolution atmospheric analysis. In the case of limited computing resources one has typically to make a compromise between spatial resolution and the duration of the simulated period, both of which can limit the quality of the wind farm siting. A common method to estimate maximum winds is to fit an extreme value distribution (e.g. Gumbel, gev or Pareto) to the maximum values of each year of available data, or the tail of these values. If data are only available for a short period, e.g. 10 or 15 years, then this will give a rather inaccurate estimate. It is possible to deal with this problem by utilizing monthly or weekly maxima, but this introduces new problems: seasonal variation, autocorrelation of neighboring values, and increased discrepancy between data and fitted distribution. We introduce a new method to estimate return periods of extreme values of winds at hub height from relatively short time series of winds, simulated

  16. Frequency Selection for Multi-frequency Acoustic Measurement of Suspended Sediment

    Science.gov (United States)

    Chen, X.; HO, H.; Fu, X.

    2017-12-01

    Multi-frequency acoustic measurement of suspended sediment has found successful applications in marine and fluvial environments. Difficult challenges remain in regard to improving its effectiveness and efficiency when applied to high concentrations and wide size distributions in rivers. We performed a multi-frequency acoustic scattering experiment in a cylindrical tank with a suspension of natural sands. The sands range from 50 to 600 μm in diameter with a lognormal size distribution. The bulk concentration of suspended sediment varied from 1.0 to 12.0 g/L. We found that the commonly used linear relationship between the intensity of acoustic backscatter and suspended sediment concentration holds only at sufficiently low concentrations, for instance below 3.0 g/L. It fails at a critical value of concentration that depends on measurement frequency and the distance between the transducer and the target point. Instead, an exponential relationship was found to work satisfactorily throughout the entire range of concentration. The coefficient and exponent of the exponential function changed, however, with the measuring frequency and distance. Considering the increased complexity of inverting the concentration values when an exponential relationship prevails, we further analyzed the relationship between measurement error and measuring frequency. It was also found that the inversion error may be effectively controlled within 5% if the frequency is properly set. Compared with concentration, grain size was found to heavily affect the selection of optimum frequency. A regression relationship for optimum frequency versus grain size was developed based on the experimental results.

  17. Time-Frequency Data Reduction for Event Related Potentials: Combining Principal Component Analysis and Matching Pursuit

    Directory of Open Access Journals (Sweden)

    Selin Aviyente

    2010-01-01

    Full Text Available Joint time-frequency representations offer a rich representation of event related potentials (ERPs that cannot be obtained through individual time or frequency domain analysis. This representation, however, comes at the expense of increased data volume and the difficulty of interpreting the resulting representations. Therefore, methods that can reduce the large amount of time-frequency data to experimentally relevant components are essential. In this paper, we present a method that reduces the large volume of ERP time-frequency data into a few significant time-frequency parameters. The proposed method is based on applying the widely used matching pursuit (MP approach, with a Gabor dictionary, to principal components extracted from the time-frequency domain. The proposed PCA-Gabor decomposition is compared with other time-frequency data reduction methods such as the time-frequency PCA approach alone and standard matching pursuit methods using a Gabor dictionary for both simulated and biological data. The results show that the proposed PCA-Gabor approach performs better than either the PCA alone or the standard MP data reduction methods, by using the smallest amount of ERP data variance to produce the strongest statistical separation between experimental conditions.

  18. Prioritizing quality over profit : Value trade-offs within architect-client relations

    NARCIS (Netherlands)

    Bos-De Vos, M.; Volker, L.; Wamelink, J.W.F.

    2015-01-01

    Architectural service delivery involves a complex system of economic and quality related value dimensions, which are mutually dependent and prioritized differently by actors. Responding to professional logics as well as organizational logics, value creation goals of architects and clients are

  19. Effects of low-frequency repetitive transcranial magnetic stimulation on event-related potential P300

    Science.gov (United States)

    Torii, Tetsuya; Sato, Aya; Iwahashi, Masakuni; Iramina, Keiji

    2012-04-01

    The present study analyzed the effects of repetitive transcranial magnetic stimulation (rTMS) on brain activity. P300 latency of event-related potential (ERP) was used to evaluate the effects of low-frequency and short-term rTMS by stimulating the supramarginal gyrus (SMG), which is considered to be the related area of P300 origin. In addition, the prolonged stimulation effects on P300 latency were analyzed after applying rTMS. A figure-eight coil was used to stimulate left-right SMG, and intensity of magnetic stimulation was 80% of motor threshold. A total of 100 magnetic pulses were applied for rTMS. The effects of stimulus frequency at 0.5 or 1 Hz were determined. Following rTMS, an odd-ball task was performed and P300 latency of ERP was measured. The odd-ball task was performed at 5, 10, and 15 min post-rTMS. ERP was measured prior to magnetic stimulation as a control. Electroencephalograph (EEG) was measured at Fz, Cz, and Pz that were indicated by the international 10-20 electrode system. Results demonstrated that different effects on P300 latency occurred between 0.5-1 Hz rTMS. With 1 Hz low-frequency magnetic stimulation to the left SMG, P300 latency decreased. Compared to the control, the latency time difference was approximately 15 ms at Cz. This decrease continued for approximately 10 min post-rTMS. In contrast, 0.5 Hz rTMS resulted in delayed P300 latency. Compared to the control, the latency time difference was approximately 20 ms at Fz, and this delayed effect continued for approximately 15 min post-rTMS. Results demonstrated that P300 latency varied according to rTMS frequency. Furthermore, the duration of the effect was not similar for stimulus frequency of low-frequency rTMS.

  20. Testing General Relativity with Low-Frequency, Space-Based Gravitational-Wave Detectors.

    Science.gov (United States)

    Gair, Jonathan R; Vallisneri, Michele; Larson, Shane L; Baker, John G

    2013-01-01

    We review the tests of general relativity that will become possible with space-based gravitational-wave detectors operating in the ∼ 10 -5 - 1 Hz low-frequency band. The fundamental aspects of gravitation that can be tested include the presence of additional gravitational fields other than the metric; the number and tensorial nature of gravitational-wave polarization states; the velocity of propagation of gravitational waves; the binding energy and gravitational-wave radiation of binaries, and therefore the time evolution of binary inspirals; the strength and shape of the waves emitted from binary mergers and ringdowns; the true nature of astrophysical black holes; and much more. The strength of this science alone calls for the swift implementation of a space-based detector; the remarkable richness of astrophysics, astronomy, and cosmology in the low-frequency gravitational-wave band make the case even stronger.

  1. A one-parametric formula relating the frequencies of twin-peak quasi-periodic oscillations

    Science.gov (United States)

    Török, Gabriel; Goluchová, Kateřina; Šrámková, Eva; Horák, Jiří; Bakala, Pavel; Urbanec, Martin

    2017-12-01

    Timing analysis of X-ray flux in more than a dozen low-mass X-ray binary systems containing a neutron star reveals remarkable correlations between frequencies of two characteristic peaks present in the power-density spectra. We find a simple analytic relation that well reproduces all these individual correlations. We link this relation to a physical model which involves accretion rate modulation caused by an oscillating torus.

  2. Diagnostic values for skin temperature assessment to detect diabetes-related foot complications

    NARCIS (Netherlands)

    van Netten, Jaap J.; Prijs, Miranda; van Baal, Jeff G.; Liu, Chanjuan; van der Heijden, Ferdi; Bus, Sicco A.

    2014-01-01

    Abstract Background: Skin temperature assessment is a promising modality for early detection of diabetic foot problems, but its diagnostic value has not been studied. Our aims were to investigate the diagnostic value of different cutoff skin temperature values for detecting diabetes-related foot

  3. REFLECTING OF VALUE POLICY OF INTERETHNIC RELATIONS IN THE US MEDIA

    OpenAIRE

    A. S. Frolova; O. Y. Posukhova; A. V. Serikov

    2015-01-01

    The article deals with the specifics of the US value policy in the sphere of interethnic and interracial relations. On the bases of the analysis of publications in the US media authors identify key trends and ideological constructs in building and settlement of interethnic relations. It is noted that the emerging trend is the promotion of the idea of erasing the boundaries between ethnic identities. The authors show that American society is in the process of value and ideological social and c...

  4. Low-Frequency Beacon Signal Strength Determination.

    Science.gov (United States)

    1980-01-01

    Radio Frequency List , RIS AF-6050-12 [141. Using this value and assum- ing performance for these facilities as indicatcd in FAA Handbook 6050.10, ERP...FAA Handbook 6050. 10 for facilities of appropriate transmitter power, determined from FAA Master Radio Frequency List 6050-12, April 1979...these facilities has not been directly measured and, therefore, values corresponding to transmitter powers given in FAA Master Radio Frequency List , RIS

  5. Sex Comparisons for Relative Peak Torque and Electromyographic Mean Frequency during Fatigue

    Science.gov (United States)

    Stock, Matt S.; Beck, Travis W.; DeFreitas, Jason M.; Ye, Xin

    2013-01-01

    Purpose: This study compared the relative peak torque and normalized electromyographic (EMG) mean frequency (MNF) responses during fatiguing isokinetic muscle actions for men versus women. Method: Twenty men M[subscript age] ± SD = 22 ± 2 years) and 20 women M[subscript age] ± SD = 22 ± 1 years) performed 50 maximal concentric isokinetic muscle…

  6. Diagnostic values for skin temperature assessment to detect diabetes-related foot complications

    NARCIS (Netherlands)

    van Netten, Jaap J.; Prijs, Miranda; van Baal, Jeff G.; Liu, C.; van der Heijden, Ferdinand; Bus, Sicco A.

    2014-01-01

    Skin temperature assessment is a promising modality for early detection of diabetic foot problems, but its diagnostic value has not been studied. Our aims were to investigate the diagnostic value of different cutoff skin temperature values for detecting diabetes-related foot complications such as

  7. The moderating effect of conformism values on the relations between other personal values, social norms, moral obligation, and single altruistic behaviours.

    Science.gov (United States)

    Lönnqvist, Jan-Erik; Walkowitz, Gari; Wichardt, Philipp; Lindeman, Marjaana; Verkasalo, Markku

    2009-09-01

    Three studies predicted and found that the individual's conformism values are one determinant of whether behaviour is guided by other personal values or by social norms. In Study 1 (N=50), pro-gay law reform participants were told they were either in a minority or a majority in terms of their attitude towards the law reform. Only participants who were high in conformism values conformed to the group norm on public behaviour intentions. In studies 2 (N=42) and 3 (N=734), participants played multiple choice prisoner's dilemma games with monetary incentives. Only participants who considered conformism values to be relatively unimportant showed the expected connections between universalism values and altruistic behaviour. Study 3 also established that the moderating effect of conformism values on the relation between universalism values and altruistic behaviour was mediated through experienced sense of moral obligation.

  8. Frequency domain Monte Carlo simulation method for cross power spectral density driven by periodically pulsed spallation neutron source using complex-valued weight Monte Carlo

    International Nuclear Information System (INIS)

    Yamamoto, Toshihiro

    2014-01-01

    Highlights: • The cross power spectral density in ADS has correlated and uncorrelated components. • A frequency domain Monte Carlo method to calculate the uncorrelated one is developed. • The method solves the Fourier transformed transport equation. • The method uses complex-valued weights to solve the equation. • The new method reproduces well the CPSDs calculated with time domain MC method. - Abstract: In an accelerator driven system (ADS), pulsed spallation neutrons are injected at a constant frequency. The cross power spectral density (CPSD), which can be used for monitoring the subcriticality of the ADS, is composed of the correlated and uncorrelated components. The uncorrelated component is described by a series of the Dirac delta functions that occur at the integer multiples of the pulse repetition frequency. In the present paper, a Monte Carlo method to solve the Fourier transformed neutron transport equation with a periodically pulsed neutron source term has been developed to obtain the CPSD in ADSs. Since the Fourier transformed flux is a complex-valued quantity, the Monte Carlo method introduces complex-valued weights to solve the Fourier transformed equation. The Monte Carlo algorithm used in this paper is similar to the one that was developed by the author of this paper to calculate the neutron noise caused by cross section perturbations. The newly-developed Monte Carlo algorithm is benchmarked to the conventional time domain Monte Carlo simulation technique. The CPSDs are obtained both with the newly-developed frequency domain Monte Carlo method and the conventional time domain Monte Carlo method for a one-dimensional infinite slab. The CPSDs obtained with the frequency domain Monte Carlo method agree well with those with the time domain method. The higher order mode effects on the CPSD in an ADS with a periodically pulsed neutron source are discussed

  9. The functional correlation between rainfall rate and extinction coefficient for frequencies from 3 to 10 GHz

    Science.gov (United States)

    Jameson, A. R.

    1990-01-01

    The relationship between the rainfall rate (R) obtained from radiometric brightness temperatures and the extinction coefficient (k sub e) is investigated by computing the values of k sub e over a wide range of rainfall rates, for frequencies from 3 to 25 GHz. The results show that the strength of the relation between the R and the k sub e values exhibits considerable variation for frequencies at this range. Practical suggestions are made concerning the selection of particular frequencies for rain measurements to minimize the error in R determinations.

  10. Corporate values as related to occupation, gender, age, and company size.

    Science.gov (United States)

    Thumin, F J; Johnson, J H; Kuehl, C; Jiang, W Y

    1995-07-01

    A mail survey was used to study the perceived importance of 15 corporate values among advertising personnel, CPAs, and business school professors. Excellent customer service, ethical behavior, and product quality were perceived as highly important by all groups. Political activity and contribution to the community were seen as relatively unimportant. There was general agreement that it was more important to make a fair profit than to maximize profits. A number of corporate values were significantly related to occupational group, gender, age, and company size.

  11. Relation between electric properties and water saturation for hematitic sandstone with frequency

    Directory of Open Access Journals (Sweden)

    M. M. Gomaa

    2008-06-01

    Full Text Available This paper focuses on the effect of water saturation on A. C. electrical conductivity and dielectric constant of fully and partially saturated hematitic sandstone sample (Aswan area, Egypt. The saturation of the sample was changed from partial to full saturation. Complex resistivity measurements at room temperature (~16°C, were performed in the frequency range from 0.1 Hz to 100 KHz. Experimental electrical spectra indicate, generally, that the electrical conductivity and dielectric constant vary strongly with water saturations and frequency. The low frequency electrical conductivity and dielectric constant are mainly controlled by surface conduction and polarization of the electrical double layer. The behaviour of the electrical conductivity and dielectric constant, with increasing water content, were argued to the orientational polarization of bound water for very low saturations, displacement of the excess surface charges for relatively low saturations, and free exchange of excess ions in double layer with the bulk electrolyte and generation of transient diffusion potentials which lag behind the applied field for high saturations.

  12. Economic Value of Li-ion Energy Storage System in Frequency Regulation Application from Utility Firm’s Perspective in Korea

    Directory of Open Access Journals (Sweden)

    Wonchang Hur

    2015-05-01

    Full Text Available Energy Storage Systems (ESSs have recently been highlighted because of their many benefits such as load-shifting, frequency regulation, price arbitrage, renewables, and so on. Among those benefits, we aim at evaluating their economic value in frequency regulation application. However, unlike previous literature focusing on profits obtained from participating in the ancillary service market, our approach concentrates on the cost reduction from the perspective of a utility firm that has an obligation to pay energy fees to a power exchange. More specifically, we focus on the payments between the power exchange market and the utility firm as a major source of economic benefits. The evaluation is done by cost- benefit analysis (CBA with a dataset of the Korean market while considering operational constraint costs as well as scheduled energy payments, and a simulation algorithm for the evaluation is provided. Our results show the potential for huge profits to be made by cost reduction. We believe that this research can provide a guideline for a utility firm considering investing in ESSs for frequency regulation application as a source of cost reduction.

  13. The diagnostic value of high-frequency power-based diffusion-weighted imaging in prediction of neuroepithelial tumour grading

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhiye; Liu, Mengqi [Chinese PLA General Hospital, Department of Radiology, Beijing (China); Hainan Branch of Chinese PLA General Hospital, Department of Radiology, Sanya (China); Zhou, Peng [Chinese Academy of Sciences, Research Center for Brain-inspired Intelligence, Institute of Automation, Beijing (China); University of Chinese Academy of Sciences, Beijing (China); Lv, Bin [Academy of Telecommunication Research of MIIT, Beijing (China); Wang, Yan; Wang, Yulin; Lou, Xin; Ma, Lin [Chinese PLA General Hospital, Department of Radiology, Beijing (China); Gui, Qiuping [Chinese PLA General Hospital, Department of Pathology, Beijing (China); He, Huiguang [Chinese Academy of Sciences, Research Center for Brain-inspired Intelligence, Institute of Automation, Beijing (China); University of Chinese Academy of Sciences, Beijing (China); Chinese Academy of Sciences, Center for Excellence in Brain Science and Intelligence Technology, Beijing (China)

    2017-12-15

    To retrospectively evaluate the diagnostic value of high-frequency power (HFP) compared with the minimum apparent diffusion coefficient (MinADC) in the prediction of neuroepithelial tumour grading. Diffusion-weighted imaging (DWI) data were acquired on 115 patients by a 3.0-T MRI system, which included b0 images and b1000 images over the whole brain in each patient. The HFP values and MinADC values were calculated by an in-house script written on the MATLAB platform. There was a significant difference among each group excluding grade I (G1) vs. grade II (G2) (P = 0.309) for HFP and among each group for MinADC. ROC analysis showed a higher discriminative accuracy between low-grade glioma (LGG) and high-grade glioma (HGG) for HFP with area under the curve (AUC) value 1 compared with that for MinADC with AUC 0.83 ± 0.04 and also demonstrated a higher discriminative ability among the G1-grade IV (G4) group for HFP compared with that for MinADC except G1 vs. G2. HFP could provide a simple and effective optimal tool for the prediction of neuroepithelial tumour grading based on diffusion-weighted images in routine clinical practice. (orig.)

  14. The relative importance of fluid and kinetic frequency shifts of an electron plasma wave

    International Nuclear Information System (INIS)

    Winjum, B. J.; Fahlen, J.; Mori, W. B.

    2007-01-01

    The total nonlinear frequency shift of a plasma wave including both fluid and kinetic effects is estimated when the phase velocity of the wave is much less than the speed of light. Using a waterbag or fluid model, the nonlinear frequency shift due to harmonic generation is calculated for an arbitrary shift in the wavenumber. In the limit where the wavenumber does not shift, the result is in agreement with previously published work [R. L. Dewar and J. Lindl, Phys. Fluids 15, 820 (1972); T. P. Coffey, ibid. 14, 1402 (1971)]. This shift is compared to the kinetic shift of Morales and O'Neil [G. J. Morales and T. M. O'Neil, Phys. Rev. Lett. 28, 417 (1972)] for wave amplitudes and values of kλ D of interest to Raman backscatter of a laser driver in inertial confinement fusion

  15. The relative importance of fluid and kinetic frequency shifts of an electron plasma wave

    Science.gov (United States)

    Winjum, B. J.; Fahlen, J.; Mori, W. B.

    2007-10-01

    The total nonlinear frequency shift of a plasma wave including both fluid and kinetic effects is estimated when the phase velocity of the wave is much less than the speed of light. Using a waterbag or fluid model, the nonlinear frequency shift due to harmonic generation is calculated for an arbitrary shift in the wavenumber. In the limit where the wavenumber does not shift, the result is in agreement with previously published work [R. L. Dewar and J. Lindl, Phys. Fluids 15, 820 (1972); T. P. Coffey, Phys. Fluids 14, 1402 (1971)]. This shift is compared to the kinetic shift of Morales and O'Neil [G. J. Morales and T. M. O'Neil, Phys. Rev. Lett. 28, 417 (1972)] for wave amplitudes and values of kλD of interest to Raman backscatter of a laser driver in inertial confinement fusion.

  16. Testing General Relativity with Low-Frequency, Space-Based Gravitational-Wave Detectors

    Directory of Open Access Journals (Sweden)

    John G. Baker

    2013-09-01

    Full Text Available We review the tests of general relativity that will become possible with space-based gravitational-wave detectors operating in the ∼ 10^{-5} – 1 Hz low-frequency band. The fundamental aspects of gravitation that can be tested include the presence of additional gravitational fields other than the metric; the number and tensorial nature of gravitational-wave polarization states; the velocity of propagation of gravitational waves; the binding energy and gravitational-wave radiation of binaries, and therefore the time evolution of binary inspirals; the strength and shape of the waves emitted from binary mergers and ringdowns; the true nature of astrophysical black holes; and much more. The strength of this science alone calls for the swift implementation of a space-based detector; the remarkable richness of astrophysics, astronomy, and cosmology in the low-frequency gravitational-wave band make the case even stronger.

  17. Frequency-dependent brain regional homogeneity alterations in patients with mild cognitive impairment during working memory state relative to resting state

    Directory of Open Access Journals (Sweden)

    Pengyun eWang

    2016-03-01

    Full Text Available Several studies have reported working memory deficits in patients with mild cognitive impairment (MCI. However, previous studies investigating the neural mechanisms of MCI have primarily focused on brain activity alterations during working memory tasks. No study to date has compared brain network alterations in the working memory state between MCI patients and normal control subjects. Therefore, using the index of regional homogeneity (ReHo, we explored brain network impairments in MCI patients during a working memory task relative to the resting state, and identified frequency-dependent effects in separate frequency bands.Our results indicate that, in MCI patients, ReHo is altered in the posterior cingulate cortex in the slow-3 band (0.073–0.198 Hz, and in the bottom of the right occipital lobe and part of the right cerebellum, the right thalamus, a diffusing region in the bilateral prefrontal cortex, the left and right parietal-occipital regions, and the right angular gyrus in the slow-5 band (0.01–0.027 Hz. Furthermore, in normal controls, the value of ReHo in clusters belonging to the default mode network decreased, while the value of ReHo in clusters belonging to the attentional network increased during the task state. However, this pattern was reversed in MCI patients, and was associated with decreased working memory performance. In addition, we identified altered functional connectivity of the abovementioned regions with other parts of the brain in MCI patients.This is the first study to compare frequency-dependent alterations of ReHo in MCI patients between resting and working memory states. The results provide a new perspective regarding the neural mechanisms of working memory deficits in MCI patients, and extend our knowledge of altered brain patterns in resting and task-evoked states.

  18. Prestress Force Identification for Externally Prestressed Concrete Beam Based on Frequency Equation and Measured Frequencies

    Directory of Open Access Journals (Sweden)

    Luning Shi

    2014-01-01

    Full Text Available A prestress force identification method for externally prestressed concrete uniform beam based on the frequency equation and the measured frequencies is developed. For the purpose of the prestress force identification accuracy, we first look for the appropriate method to solve the free vibration equation of externally prestressed concrete beam and then combine the measured frequencies with frequency equation to identify the prestress force. To obtain the exact solution of the free vibration equation of multispan externally prestressed concrete beam, an analytical model of externally prestressed concrete beam is set up based on the Bernoulli-Euler beam theory and the function relation between prestress variation and vibration displacement is built. The multispan externally prestressed concrete beam is taken as the multiple single-span beams which must meet the bending moment and rotation angle boundary conditions, the free vibration equation is solved using sublevel simultaneous method and the semi-analytical solution of the free vibration equation which considered the influence of prestress on section rigidity and beam length is obtained. Taking simply supported concrete beam and two-span concrete beam with external tendons as examples, frequency function curves are obtained with the measured frequencies into it and the prestress force can be identified using the abscissa of the crosspoint of frequency functions. Identification value of the prestress force is in good agreement with the test results. The method can accurately identify prestress force of externally prestressed concrete beam and trace the trend of effective prestress force.

  19. Reproducibility of frequency-dependent low frequency fluctuations in reaction time over time and across tasks.

    Science.gov (United States)

    Liu, Zan-Zan; Qu, Hui-Jie; Tian, Zhuo-Ling; Han, Meng-Jian; Fan, Yi; Ge, Lie-Zhong; Zang, Yu-Feng; Zhang, Hang

    2017-01-01

    Increased levels of reaction time variability (RTV) are characteristics of sustained attention deficits. The clinical significance of RTV has been widely recognized. However, the reliability of RTV measurements has not been widely studied. The present study aimed to assess the test-retest reliability of RTV conventional measurements, e.g., the standard deviation (SD), the coefficient of variation (CV), and a new measurement called the amplitude of low frequency fluctuation (ALFF) of RT. In addition, we aimed to assess differences and similarities of these measurements between different tasks. Thirty-seven healthy college students participated in 2 tasks, i.e., an Eriksen flanker task (EFT) and a simple reaction task (SRT), twice over a mean interval of 56 days. Conventional measurements of RTV including RT-SD and RT-CV were assessed first. Then the RT time series were converted into frequency domains, and RT-ALFF was further calculated for the whole frequency band (0.0023-0.167 Hz) and for a few sub-frequency bands including Slow-6 (frequency bands (Slow-3), but SRT RT-ALFF values showed slightly higher ICC values than EFT values in lower frequency bands (Slow-5 and Slow-4). 2) RT-ALFF magnitudes in each sub-frequency band were greater for the SRT than those for the EFT. 3) The RT-ALFF in the Slow-4 of the EFT was found to be correlated with the RT-ALFF in the Slow-5 of the SRT for both two visits, but no consistently significant correlation was found between the same frequency bands. These findings reveal good test-retest reliability for conventional measurements and for the RT-ALFF of RTV. The RT-ALFF presented frequency-dependent similarities across tasks. All of our results reveal the presence of different frequency structures between the two tasks, and thus the frequency-dependent characteristics of different tasks deserve more attention in future studies.

  20. Psycholexical Value Factors in Spain and Their Relation with Personality Traits

    NARCIS (Netherlands)

    Morales-Vives, Fabia; De Raad, Boele; Vigil-Colet, Andreu

    2012-01-01

    The aim of the present study is to determine the structure of values in the Spanish population and its relation to the Big Five personality traits. Using a psycholexical approach, 566 words were identified as values and administered to a sample of participants who were instructed to rate the extent

  1. Reproducibility and relative validity of a semi-quantitative food-frequency questionnaire in an adult population of Rosario, Argentina

    OpenAIRE

    María Elisa Zapata; Romina Buffarini; Nadia Lingiardi; Ana Luiza Gonçalves-Soares

    2016-01-01

    Introduction: Dietary assessment of nutrients and food groups by food frequency questionnaire needs to be validated in each population. The objective of this cross-sectional study was to evaluate the reproducibility and relative validity of a semi-quantitative food frequency questionnaire among adults of Rosario, Argentina.Material and Methods: Two food frequency questionnaires and four 24-hour dietary recalls were applied in a sample of 88 adults. Reproducibility of food frequency questionna...

  2. Firewater system inadvertent actuation frequencies

    International Nuclear Information System (INIS)

    Schroeder, J.A.; Eide, S.A.

    1993-01-01

    This paper presents some recommended generic values for fire protection system inadvertent actuation frequencies. The frequencies are based on actual data from Department of Energy and commercial reactor plant facilities

  3. The Potential Effect of Sea Level Rise on Coastal Property Values

    Science.gov (United States)

    O'Donnell, J.

    2015-12-01

    It is well established that one consequence of increasing global sea level is that the frequency of flooding at low-lying coastal sites will increase. We review recent evidence that the effects coastal geometry will create substantial spatial variations in the changes in flooding frequency with scales of order 100km. Using a simple model of the evolution of coastal property values we demonstrate that a consequence of sea level rise is that the appreciation of coastal properties will peak, and then decline relative to higher properties. The time when the value reach a maximum is shown to depend upon the demand for the coastal property, and the local rate of change of flooding frequency due to sea level rise. The simple model is then extended to include, in an elementary manner, the effects on the value of adjacent but higher properties. We show that the effect of increased flooding frequency of the lower properties leads to an accelerated appreciation of the value of upland properties and an accelerated decline in the value of the coastal properties. We then provide some example calculations for selected sites. We conclude with a discussion of comparisons of the prediction of the analyses to recent data, and then comments on the impact of sea level rise on tax base of coastal communities.

  4. Analysis of the Value Creation in Higher Institutions: A Relational Perspective

    Directory of Open Access Journals (Sweden)

    Raquel SÁNCHEZ-FERNÁNDEZ

    2010-10-01

    Full Text Available Despite the growing interest in value creation, a review of the relevant educational literature reveals that there is no generally accepted and empirically confirmed relational model of the student value creation process. This paper contributes in this way, analyzing several antecedents and consequences in the value creation process between graduates and their universities. We therefore study the effects of the quality of the student-professor interaction, trust, and university image on student perceived value. Moreover, we analyze the impact of perceived value on student satisfaction and loyalty. An empirical study was carried out in order to test the proposed theoretical model. The findings provide relevant academic and managerial implications for strategic decisionmaking at universities.

  5. Density and relative frequency effects on competitive interactions and resource use in pea–barley intercrops

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Andersen, H.K.; Jørnsgaard, B.

    2006-01-01

    or specific grain yield composition are wanted. Keywords: Competition dynamics; Grain quality; Hordeum vulgare; Intercropping; Nitrogen use; Organic farming; Pisum sativum; Weeds; Yield Abbreviations: IC, mixed intercropping; LER, land equivalent ratio; N, nitrogen; REIc, relative efficiency index; SC, sole...... not increase its reliance on atmospheric nitrogen fixation compared to the pea sole crop. With respect to soil nitrogen uptake there were no effect of plant density but a strong effect of the relative frequency of pea in the intercrop, the greater the proportion the lower the uptake. Changes in the competitive...... and tillering ability of barley are seen as likely explanations of lower weed load in the barley dominated crop treatments. This study points at the potential of employing density and relative crop frequency as "regulators" when specific intercrop objectives such as increased competitiveness towards weeds...

  6. Selective attention modulates human auditory brainstem responses: relative contributions of frequency and spatial cues.

    Directory of Open Access Journals (Sweden)

    Alexandre Lehmann

    Full Text Available Selective attention is the mechanism that allows focusing one's attention on a particular stimulus while filtering out a range of other stimuli, for instance, on a single conversation in a noisy room. Attending to one sound source rather than another changes activity in the human auditory cortex, but it is unclear whether attention to different acoustic features, such as voice pitch and speaker location, modulates subcortical activity. Studies using a dichotic listening paradigm indicated that auditory brainstem processing may be modulated by the direction of attention. We investigated whether endogenous selective attention to one of two speech signals affects amplitude and phase locking in auditory brainstem responses when the signals were either discriminable by frequency content alone, or by frequency content and spatial location. Frequency-following responses to the speech sounds were significantly modulated in both conditions. The modulation was specific to the task-relevant frequency band. The effect was stronger when both frequency and spatial information were available. Patterns of response were variable between participants, and were correlated with psychophysical discriminability of the stimuli, suggesting that the modulation was biologically relevant. Our results demonstrate that auditory brainstem responses are susceptible to efferent modulation related to behavioral goals. Furthermore they suggest that mechanisms of selective attention actively shape activity at early subcortical processing stages according to task relevance and based on frequency and spatial cues.

  7. A New Value Classification and Values to Be Acquired by Students Related to This Classification

    Science.gov (United States)

    Acat, M. Bahaddin; Aslan, Mecit

    2012-01-01

    The aim of this study is to access a new value classification and analyse the views of teacher and parents related to this classification. The general survey model was employed in this study. The population of this study is composed of school teachers working in primary schools and parents of their students in Eskisehir. The present study adopted…

  8. How Epistemological Beliefs Relate to Values and Gender Orientation

    Science.gov (United States)

    Kessels, Ursula

    2013-01-01

    In response to the current literature on possible systematic differences in the epistemological beliefs of men and women and between members of different cultures, this paper examines the way psychological constructs associated with gender (i.e. gender orientation) and culture (i.e. values) are related to individual's epistemological beliefs.…

  9. Value Relativism and Perspective Taking are Two Distinct Facets of Wisdom-Related Knowledge.

    Science.gov (United States)

    Kunzmann, Ute; Nowak, Jana; Thomas, Stefanie; Nestler, Steffen

    2017-12-18

    There has been mixed evidence for age differences in wisdom-related knowledge across the adult life span. This study investigated two potential moderators of the link between age and wisdom-related knowledge: the wisdom criteria and the wisdom tasks. To test these moderators, 40 younger and 40 older participants completed four wisdom tasks differing in context-richness. Independent trained raters coded the resulting think-aloud protocols in terms of value relativism, as defined in the Berlin wisdom paradigm, and perspective taking, as defined by Grossmann. The type of task did not show any main or interaction effects on the present two wisdom criteria. However, age differences in the two wisdom criteria were multidirectional: whereas perspective taking did not differ by age group, value relativism was lower in older than younger adults. In addition, value relativism, but not perspective taking, was related to measures of fluid and crystallized intelligence, whereas perspective taking, but not value relativism, was related to a measure of life investment. This study provides evidence for the idea that value relativism and perspective taking are two distinct facets of wisdom-related knowledge. Implications for future age-comparative research interested in wisdom are discussed. © The Author(s) 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Calcium Input Frequency, Duration and Amplitude Differentially Modulate the Relative Activation of Calcineurin and CaMKII

    Science.gov (United States)

    Li, Lu; Stefan, Melanie I.; Le Novère, Nicolas

    2012-01-01

    NMDA receptor dependent long-term potentiation (LTP) and long-term depression (LTD) are two prominent forms of synaptic plasticity, both of which are triggered by post-synaptic calcium elevation. To understand how calcium selectively stimulates two opposing processes, we developed a detailed computational model and performed simulations with different calcium input frequencies, amplitudes, and durations. We show that with a total amount of calcium ions kept constant, high frequencies of calcium pulses stimulate calmodulin more efficiently. Calcium input activates both calcineurin and Ca2+/calmodulin-dependent protein kinase II (CaMKII) at all frequencies, but increased frequencies shift the relative activation from calcineurin to CaMKII. Irrespective of amplitude and duration of the inputs, the total amount of calcium ions injected adjusts the sensitivity of the system to calcium input frequencies. At a given frequency, the quantity of CaMKII activated is proportional to the total amount of calcium. Thus, an input of a small amount of calcium at high frequencies can induce the same activation of CaMKII as a larger amount, at lower frequencies. Finally, the extent of activation of CaMKII signals with high calcium frequency is further controlled by other factors, including the availability of calmodulin, and by the potency of phosphatase inhibitors. PMID:22962589

  11. Sex ratios, mating frequencies and relative abundance of sympatric millipedes in the genus Chersastus (Diplopoda: Pachybolidae

    Directory of Open Access Journals (Sweden)

    Mark Ian Cooper

    2014-12-01

    Full Text Available Three hypotheses exist for explaining climbing behavior in millipedes: 1 waterlogging, 2 detritus limiting, and 3 mate avoidance. Data of sex ratios, mating frequency and relative abundance are provided to suggest an alternative explanation for the pattern in sympatric forest millipedes. Sex ratio differences - from equality - were tested using a G-test comparing millipedes on and above ground. Mating frequencies were calculated based on the percentage of paired individuals. Relative abundance may correlate with male-biases in the sex ratios. All three factors suggest Chersastus inscriptus has a higher reproductive potential than C. anulatus. This is evidence for mating hotspots.

  12. Relative importance of precipitation frequency and intensity in inter-annual variation of precipitation in Singapore during 1980-2013

    Science.gov (United States)

    Li, Xin; Babovic, Vladan

    2017-04-01

    Observed studies on inter-annual variation of precipitation provide insight into the response of precipitation to anthropogenic climate change and natural climate variability. Inter-annual variation of precipitation results from the concurrent variations of precipitation frequency and intensity, understanding of the relative importance of frequency and intensity in the variability of precipitation can help fathom its changing properties. Investigation of the long-term changes of precipitation schemes has been extensively carried out in many regions across the world, however, detailed studies of the relative importance of precipitation frequency and intensity in inter-annual variation of precipitation are still limited, especially in the tropics. Therefore, this study presents a comprehensive framework to investigate the inter-annual variation of precipitation and the dominance of precipitation frequency and intensity in a tropical urban city-state, Singapore, based on long-term (1980-2013) daily precipitation series from 22 rain gauges. First, an iterative Mann-Kendall trend test method is applied to detect long-term trends in precipitation total, frequency and intensity at both annual and seasonal time scales. Then, the relative importance of precipitation frequency and intensity in inducing the inter-annual variation of wet-day precipitation total is analyzed using a dominance analysis method based on linear regression. The results show statistically significant upward trends in wet-day precipitation total, frequency and intensity at annual time scale, however, these trends are not evident during the monsoon seasons. The inter-annual variation of wet-day precipitation is mainly dominated by precipitation intensity for most of the stations at annual time scale and during the Northeast monsoon season. However, during the Southwest monsoon season, the inter-annual variation of wet-day precipitation is mainly dominated by precipitation frequency. These results have

  13. Frequency of aneuploidy related to age in porcine oocytes.

    Directory of Open Access Journals (Sweden)

    Miroslav Hornak

    Full Text Available It is generally accepted that mammalian oocytes are frequently suffering from chromosome segregation errors during meiosis I, which have severe consequences, including pregnancy loss, developmental disorders and mental retardation. In a search for physiologically more relevant model than rodent oocytes to study this phenomenon, we have employed comparative genomic hybridization (CGH, combined with whole genome amplification (WGA, to study the frequency of aneuploidy in porcine oocytes, including rare cells obtained from aged animals. Using this method, we were able to analyze segregation pattern of each individual chromosome during meiosis I. In contrast to the previous reports where conventional methods, such as chromosome spreads or FISH, were used to estimate frequency of aneuploidy, our results presented here show, that the frequency of this phenomenon was overestimated in porcine oocytes. Surprisingly, despite the results from human and mouse showing an increase in the frequency of aneuploidy with advanced maternal age, our results obtained by the most accurate method currently available for scoring the aneuploidy in oocytes indicated no increase in the frequency of aneuploidy even in oocytes from animals, whose age was close to the life expectancy of the breed.

  14. Flood-frequency characteristics of Wisconsin streams

    Science.gov (United States)

    Walker, John F.; Peppler, Marie C.; Danz, Mari E.; Hubbard, Laura E.

    2017-05-22

    Flood-frequency characteristics for 360 gaged sites on unregulated rural streams in Wisconsin are presented for percent annual exceedance probabilities ranging from 0.2 to 50 using a statewide skewness map developed for this report. Equations of the relations between flood-frequency and drainage-basin characteristics were developed by multiple-regression analyses. Flood-frequency characteristics for ungaged sites on unregulated, rural streams can be estimated by use of the equations presented in this report. The State was divided into eight areas of similar physiographic characteristics. The most significant basin characteristics are drainage area, soil saturated hydraulic conductivity, main-channel slope, and several land-use variables. The standard error of prediction for the equation for the 1-percent annual exceedance probability flood ranges from 56 to 70 percent for Wisconsin Streams; these values are larger than results presented in previous reports. The increase in the standard error of prediction is likely due to increased variability of the annual-peak discharges, resulting in increased variability in the magnitude of flood peaks at higher frequencies. For each of the unregulated rural streamflow-gaging stations, a weighted estimate based on the at-site log Pearson type III analysis and the multiple regression results was determined. The weighted estimate generally has a lower uncertainty than either the Log Pearson type III or multiple regression estimates. For regulated streams, a graphical method for estimating flood-frequency characteristics was developed from the relations of discharge and drainage area for selected annual exceedance probabilities. Graphs for the major regulated streams in Wisconsin are presented in the report.

  15. Effects of weak nonlinearity on dispersion relations and frequency band-gaps of periodic structures

    DEFF Research Database (Denmark)

    Sorokin, Vladislav; Thomsen, Jon Juel

    2015-01-01

    of these for nonlinear problems is impossible or cumbersome, since Floquet theory is applicable for linear systems only. Thus the nonlinear effects for periodic structures are not yet fully uncovered, while at the same time applica-tions may demand effects of nonlinearity on structural response to be accounted for....... The present work deals with analytically predicting dynamic responses for nonlinear continuous elastic periodic structures. Specifically, the effects of weak nonlinearity on the dispersion re-lation and frequency band-gaps of a periodic Bernoulli-Euler beam performing bending os-cillations are analyzed......The analysis of the behaviour of linear periodic structures can be traced back over 300 years, to Sir Isaac Newton, and still attracts much attention. An essential feature of periodic struc-tures is the presence of frequency band-gaps, i.e. frequency ranges in which waves cannot propagate...

  16. Journalists' and Public Relations Practitioners' News Values: Perceptions and Cross-Perceptions.

    Science.gov (United States)

    Sallot, Lynne M.; Steinfatt, Thomas M.; Salwen, Michael B.

    1998-01-01

    Contributes to research on the relationship between journalism and public relations by surveying journalists and public relations practitioners. Shows that the two groups share generally similar news values, but that journalists were largely unaware of this similarity. Finds that practitioners, expecting contributions of social good by public…

  17. Examining the Relation between Social Values Perception and Moral Maturity Level of Folk Dancers

    Science.gov (United States)

    Dogan, Pinar Karacan

    2018-01-01

    The purpose of the present study is to examine the relation between social values perceptions and moral maturity levels of folk dancers, and evaluate this relation in terms of some variables. The relational screening model was used in the study. The "Multi-dimensional Social Values Scale," which was developed by Bolat (2013), and the…

  18. Weighted combination of LOD values oa splitted into frequency windows

    Science.gov (United States)

    Fernandez, L. I.; Gambis, D.; Arias, E. F.

    In this analysis a one-day combined time series of LOD(length-of-day) estimates is presented. We use individual data series derived by 7 GPS and 3 SLR analysis centers, which routinely contribute to the IERS database over a recent 27-month period (Jul 1996 - Oct 1998). The result is compared to the multi-technique combined series C04 produced by the Central Bureau of the IERS that is commonly used as a reference for the study of the phenomena of Earth rotation variations. The Frequency Windows Combined Series procedure brings out a time series, which is close to C04 but shows an amplitude difference that might explain the evident periodic behavior present in the differences of these two combined series. This method could be useful to generate a new time series to be used as a reference in the high frequency variations of the Earth rotation studies.

  19. Nobody likes premies: the relative value of patients' lives.

    Science.gov (United States)

    Janvier, A; Leblanc, I; Barrington, K J

    2008-12-01

    The objective of this study was to examine whether patient selection or triage requires placing a relative value on human lives and whether the values placed on these lives are consistent with current ethical theories. An anonymous questionnaire was administered to groups of physicians and students in Montreal. It presented eight currently incompetent patients with potential neurological sequelae requiring emergency care. Predicted outcomes were explicitly described. Four patients had a predicted 50% survival and a 50% chance of impairment; they were a preterm and a term neonate, a 2-month-old and a 50-year-old. Two already disabled patients, a 7-year-old and an 80-year-old, had 50% predicted survival. A 14-year-old and a 35-year-old had 5% survival, but differing impairment. Respondents were asked if they would resuscitate and in what order they would resuscitate if all needed intervention simultaneously. Eighty-five percent response rate, n=524. The proportion stating they would always resuscitate was smallest for the 80-year-old (18% Pold (53 and 58%, Pold and the 7-year-old would be resuscitated most frequently (74 and 77%, Pold, followed by the 7-year-old, the 14-year-old, the term newborn, the 50-year-old, the 35-year-old, the premature newborn and the 80-year-old. Order of resuscitation was not closely related to the predicted survival, impairment or potential life years gained. Age appeared to have a strong influence, with children's lives being valued more than the adults'. This tendency was reversed for the newborn infants who were undervalued compared with older children, and most particularly for the premature. The value placed on the life of newborns, in particular the premature, is less than that expected by any objective medical data and was not consistent with any ethical theory that we tested.

  20. The Investigation of Median Frequency Changes in Paraspinal Muscles Following Fatigue

    Directory of Open Access Journals (Sweden)

    Saeed Talebian

    2009-10-01

    Conclusion: Median frequency shift toward low values following fatigue in global and local paraspinal muscles was seen. However, median frequency values for the local stabilizer muscle were higher than median frequency values for the global muscles.

  1. Approaching Chinese Freedom: A Study in Absolute and Relative Values

    Directory of Open Access Journals (Sweden)

    David Kelly

    2013-01-01

    Full Text Available The rise of stability preservation to dominance in the political order coincided with a highly charged debate over “universal values” and a closely related discussion of a “China Model”. This paper analyses the critique of universal values as a “wedge issue” that is used to pre-empt criticism of the party-state by appealing to nationalism and cultural essentialism. Taking freedom as a case in point of a universal value, it shows that, while more developed in the West, freedom has an authentic Chinese history with key watersheds in the late Qing reception of popular sovereignty and the ending of the Maoist era. The work of Wang Ruoshui, Qin Hui and Xu Jilin display some of the resources liberals now bring to “de-wedging” universal values, not least freedom. They share a refusal to regard “Western” values as essentially hostile to Chinese.

  2. Dispositional sexual motives as the mirror of values in heterosexual interpersonal relations

    Directory of Open Access Journals (Sweden)

    Igor A. Fourmanov

    2017-12-01

    Full Text Available Background. Values of sexual relations repeatedly changed throughout various culturalhistorical periods. As a result of acquiring values and norms of sexual culture many actual requirements of the personthat were significant at certainontogenetic and sociogeneticstages couldget deprived of the relevance at further stages. As the sociocultural sexual development progresses the subsequent new values, highly significant for the given person are can be shaped. The system of values finds the reflexion in hierarchy and defines dynamics of sexual motives at different stages of the course of life. Objective. The objective is to define hierarchy, sexual and age distinctions in dispositional sexual motives in early adulthood. Design. The paper regards the issue of interrelation between sexual motivation and features of gender interpersonal relations. The sexual motivation was considered as interest in a general class of related incentives, all of which provide the same basic type of satisfaction associated with sexual expression. Eight specific types of incentives intrinsic to sexual expression that motivate sexual behaviourare studied: (1 feeling valued by the partner, (2 reinforcing partners value, (3 obtaining relief from stress or negative psychological states, (4 providing care and custody through sexual interaction to improve a partner’s psychological condition, (5 enhancing feelings of personal power, (6 feeling partner’s power, (7 feeling pleasure, and (8 productive fertility. Conclusion. Disregarding gender and age,the leading position in the hierarchy of sexual disposition motives is occupied by the motives of reinforcing partner’s value, pleasure and care, and subordination position, i.e. motives of comfort, personal value, power and submission. Females in comparison with males differ by higher intensity of submissionmotives and the partner’s significance, while males manifest more force of motive of production fertility. Within the

  3. Crater size-frequency distributions and a revised Martian relative chronology

    International Nuclear Information System (INIS)

    Barlow, N.G.

    1988-01-01

    A relative plotting technique is applied to Viking 1:2M photomosaics of 25,826 Martian craters of diameter greater than 8 km and age younger than that of the Martian surface. The size-frequency distribution curves are calculated and analyzed in detail, and the results are presented in extensive tables and maps. It is found that about 60 percent of the crater-containing lithologic units, including many small volcanoes and the ridged planes, were formed during the heavy-bombardment period (HBP), while 40 percent arose after the HBP. Wide region-to-region variation in the crater density is noted, and localized age estimates are provided. 42 references

  4. Relative frequency and estimated minimal frequency of Lysosomal Storage Diseases in Brazil: Report from a Reference Laboratory

    Directory of Open Access Journals (Sweden)

    Roberto Giugliani

    2017-03-01

    Full Text Available Abstract Lysosomal storage diseases (LSDs comprise a heterogeneous group of more than 50 genetic conditions of inborn errors of metabolism (IEM caused by a defect in lysosomal function. Although there are screening tests for some of these conditions, diagnosis usually depends on specific enzyme assays, which are only available in a few laboratories around the world. A pioneer facility for the diagnosis of IEM and LSDs was established in the South of Brazil in 1982 and has served as a reference service since then. Over the past 34 years, samples from 72,797 patients were referred for investigation of IEM, and 3,211 were confirmed as having an LSD (4.41%, or 1 in 22, with 3,099 of these patients originating from Brazil. The rate of diagnosis has increased over time, in part due to the creation of diagnostic networks involving a large number of Brazilian services. These cases, referred from Brazilian regions, provide insight about the relative frequency of LSDs in the country. The large amount of data available allows for the estimation of the minimal frequency of specific LSDs in Brazil. The reported data could help to plan health care policies, as there are specific therapies available for most of the cases diagnosed.

  5. [Socioeconomic status, toothbrushing frequency, and health-related behaviors in adolescents: an analysis using the PeNSE database].

    Science.gov (United States)

    Vettore, Mario Vianna; Moysés, Samuel Jorge; Sardinha, Luciana Monteiro Vasconcelos; Iser, Betine Pinto Moehlecke

    2012-01-01

    This study investigated the association between oral and general health-related behaviors and socioeconomic status, and the relationship between health-related behaviors and toothbrushing among adolescents. The database used here was the National School-Based Health Survey (PeNSE), a cross-sectional population-based study in 2009 with students from 27 Brazilian State capitals. Socio-demographic and health-related behavior data were collected. The survey included 49,189 adolescents (47.5% males), the majority of whom were 14 years of age and enrolled in public schools. The associations between toothbrushing frequency and other health-related behaviors and socioeconomic status varied between boys and girls. Associations were observed between health-related habits and toothbrushing frequency in both sexes, but with variations according to socioeconomic status. Planning health promotion interventions for adolescents should take their individual characteristics and family and social context into account.

  6. Parametric effects of word frequency effect in memory for mixed frequency lists

    OpenAIRE

    Lohnas, Lynn J.; Kahana, Michael J.

    2013-01-01

    The word frequency paradox refers to the finding that low frequency words are better recognized than high frequency words yet high frequency words are better recalled than low frequency words. Rather than comparing separate groups of low and high frequency words, we sought to quantify the functional relation between word frequency and memory performance across the broad range of frequencies typically used in episodic memory experiments. Here we report that both low frequency and high frequenc...

  7. Relationship of the vibrational frequency of the uranyl ion with the uranium electronegativity

    International Nuclear Information System (INIS)

    Rodriguez S, A.; Martinez Q, E.

    1990-07-01

    It has been demonstrated that the vibrational asymmetric frequency of the uranyl ion, it experiences a consistent spectrochemical displacement with the variations of electronegativity of the uranium in their complexes. The values of the electronegativity of the uranium they were dear by means of calculations that it involves measures of those lengths of the connection uranium-oxygen, obtained by vibrational spectroscopy, effective nuclear charges and the Allred and Rochow equation. The results show the evidence of a natural order that relates to the vibrational frequency with the electronegativity of the uranium atom; settling down that if the electronegativity is graph against it bond length to the oxygen or to it frequency value, a simple relationship is obtained as a form to obtain clear responses in absence of complementary information. (Author)

  8. Separate recording of rationally related vibration frequencies using digital stroboscopic holographic interferometry

    International Nuclear Information System (INIS)

    Alexeenko, Igor; Gusev, Michael; Gurevich, Vadim

    2009-01-01

    A method for separate recording of rationally related vibration frequencies is presented. To record and measure the mode shape of vibrations, a synchronized stroboscopic CCD camera is used. Synchronization and control of the camera acquisition for recording stroboscopic holographic sequence has been realized. The phase for different states of the object vibration is calculated using the Fourier-transform method. Experimental results are presented, and the advantages and disadvantages of the proposed method are discussed.

  9. Measuring salient food attitudes and food-related values. An elaborated, conflicting and interdependent system.

    Science.gov (United States)

    Hauser, Mirjam; Jonas, Klaus; Riemann, Rainer

    2011-10-01

    Consumer food choice behaviour in post-industrial countries is complex and influenced by a multitude of interacting variables. This study looked at the antecedents of behaviour and examined salient food-related values and attitudes. To discover personal meanings and patterns of everyday food choices across different situations we used a qualitative approach in the form of repertory grid interviews. An analysis of the personal constructs elicited from a representative sample of 100 Swiss consumers revealed elaborated value systems. The food-related values can be summarised as: authenticity/naturalness, conviviality, health, quality/indulgence, convenience, and price. The salience of these values and their negatively evaluated counterparts differed for various social eating situations and product categories. Consumers' personal values also differed significantly from their perception of current trends in eating culture. In every-day food choices interdependent food-related values compete and are thus a possible cause of ambivalence and conflicts. The findings offer explanations of discrepancies between values/attitudes and behaviour that may be due to situational constraints and habits. Implications for companies include the need for strategic realignment to regain consumers' trust by providing comprehensive value-congruent food solutions that also consider health and ethical criteria. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Meal frequency patterns and glycemic properties of maternal diet in relation to preterm delivery: Results from a large prospective cohort study.

    Science.gov (United States)

    Englund-Ögge, Linda; Birgisdottir, Bryndis Eva; Sengpiel, Verena; Brantsæter, Anne Lise; Haugen, Margareta; Myhre, Ronny; Meltzer, Helle Margrete; Jacobsson, Bo

    2017-01-01

    Dietary habits are linked to high maternal glucose levels, associated with preterm delivery. The aim of this study was to examine the associations between meal frequency and glycemic properties of maternal diet in relation to preterm delivery. This prospective cohort study included 66,000 women from the Norwegian Mother and Child Cohort Study (MoBa). Meal frequency and food intake data were obtained from a validated food frequency questionnaire during mid-pregnancy. Principal component factor analysis was used with a data-driven approach, and three meal frequency patterns were identified: "snack meal", "main meal", and "evening meal". Pattern scores were ranked in quartiles. Glycemic index and glycemic load were estimated from table values. Intakes of carbohydrates, added sugar, and fiber were reported in grams per day and divided into quartiles. Gestational age was obtained from the Medical Birth Registry of Norway. Preterm delivery was defined as birth at meal" pattern was associated with a reduced risk of preterm delivery, with hazard ratios (HRs) of 0.89 (95% confidence interval (CI): 0.80, 0.98) and 0.90 (95% CI: 0.81, 0.99) for the third and fourth quartiles, respectively, and p for trend of 0.028. This was mainly attributed to the group of women with BMI ≥25 kg/m2, with HRs of 0.87 (95% CI: 0.79, 0.96) and 0.89 (95% CI: 0.80, 0.98) for the third and fourth quartiles, respectively, and p for trend of 0.010. There was no association between glycemic index, glycemic load, carbohydrates, added sugar, fiber, or the remaining meal frequency patterns and preterm delivery. Regular consumption of main meals (breakfast, lunch, dinner) was associated with a lower risk of preterm delivery. Diet should be further studied as potential contributing factors for preterm delivery.

  11. Tracking the time course of word-frequency effects in auditory word recognition with event-related potentials.

    Science.gov (United States)

    Dufour, Sophie; Brunellière, Angèle; Frauenfelder, Ulrich H

    2013-04-01

    Although the word-frequency effect is one of the most established findings in spoken-word recognition, the precise processing locus of this effect is still a topic of debate. In this study, we used event-related potentials (ERPs) to track the time course of the word-frequency effect. In addition, the neighborhood density effect, which is known to reflect mechanisms involved in word identification, was also examined. The ERP data showed a clear frequency effect as early as 350 ms from word onset on the P350, followed by a later effect at word offset on the late N400. A neighborhood density effect was also found at an early stage of spoken-word processing on the PMN, and at word offset on the late N400. Overall, our ERP differences for word frequency suggest that frequency affects the core processes of word identification starting from the initial phase of lexical activation and including target word selection. They thus rule out any interpretation of the word frequency effect that is limited to a purely decisional locus after word identification has been completed. Copyright © 2012 Cognitive Science Society, Inc.

  12. The Impact of Values-Job Fit and Age on Work-Related Learning

    Science.gov (United States)

    Van Den Ouweland, Loth; Van den Bossche, Piet

    2017-01-01

    Research shows that both individual and job-related factors influence a worker's work-related learning. This study combines these factors, examining the impact of fit between one's work values and job characteristics on learning. Although research indicates that fit benefits multiple work-related outcomes, little is known about the impact of fit…

  13. Amplitude of Low-Frequency Fluctuations in Multiple-Frequency Bands in Acute Mild Traumatic Brain Injury.

    Science.gov (United States)

    Zhan, Jie; Gao, Lei; Zhou, Fuqing; Bai, Lijun; Kuang, Hongmei; He, Laichang; Zeng, Xianjun; Gong, Honghan

    2016-01-01

    Functional disconnectivity during the resting state has been observed in mild traumatic brain injury (mTBI) patients during the acute stage. However, it remains largely unknown whether the abnormalities are related to specific frequency bands of the low-frequency oscillations (LFO). Here, we used the amplitude of low-frequency fluctuations (ALFF) to examine the amplitudes of LFO in different frequency bands (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.073 Hz; and typical: 0.01-0.08 Hz) in patients with acute mTBI. A total of 24 acute mTBI patients and 24 age-, sex-, and education-matched healthy controls participated in this study. In the typical band, acute mTBI patients showed lower standardized ALFF in the right middle frontal gyrus and higher standardized ALFF in the right lingual/fusiform gyrus and left middle occipital gyrus. Further analyses showed that the difference between groups was concentrated in a narrower (slow-4) frequency band. In the slow-5 band, mTBI patients only exhibited higher standardized ALFF in the occipital areas. No significant correlation between the mini-mental state examination score and the standardized ALFF value was found in any brain region in the three frequency bands. Finally, no significant interaction between frequency bands and groups was found in any brain region. We concluded that the abnormality of spontaneous brain activity in acute mTBI patients existed in the frontal lobe as well as in distributed brain regions associated with integrative, sensory, and emotional roles, and the abnormal spontaneous neuronal activity in different brain regions could be better detected by the slow-4 band. These findings might contribute to a better understanding of local neural psychopathology of acute mTBI. Future studies should take the frequency bands into account when measuring intrinsic brain activity of mTBI patients.

  14. Amplitude of low-frequency fluctuations in multiple-frequency bands in acute mild traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Jie eZhan

    2016-02-01

    Full Text Available Functional disconnectivity during the resting state has been observed in mild traumatic brain injury (mTBI patients during the acute stage. However, it remains largely unknown whether the abnormalities are related to specific frequency bands of the low-frequency oscillations (LFO. Here, we used the amplitude of low-frequency fluctuations (ALFF to examine the amplitudes of LFO in different frequency bands (slow-5: 0.01–0.027 Hz; slow-4: 0.027–0.073 Hz; and typical: 0.01–0.08 Hz in patients with acute mTBI. A total of 24 acute mTBI patients and 24 age-, sex-, and education-matched healthy controls (HC participated in this study. In the typical band, acute mTBI patients showed lower standardized ALFF in the right middle frontal gyrus and higher standardized ALFF in the right lingual/fusiform gyrus and left middle occipital gyrus. Further analyses showed that the difference between groups was concentrated in a narrower (slow-4 frequency band. In the slow-5 band, mTBI patients only exhibited higher standardized ALFF in the occipital areas. No significant correlation between the MMSE score and the standardized ALFF value was found in any brain region in the three frequency bands. Finally, no significant interaction between frequency bands and groups was found in any brain region. We concluded that the abnormality of spontaneous brain activity in acute mTBI patients existed in the frontal lobe as well as in distributed brain regions associated with integrative, sensory and emotional roles, and the abnormal spontaneous neuronal activity in different brain regions could be better detected by the slow-4 band. These findings might contribute to a better understanding of local neural psychopathology of acute mTBI. Future studies should take the frequency bands into account when measuring intrinsic brain activity of mTBI patients.

  15. Charge density fluctuation of low frequency in a dusty plasma

    Institute of Scientific and Technical Information of China (English)

    李芳; 吕保维; O.Havnes

    1997-01-01

    The charge density fluctuation of low frequency in a dusty plasma, which is derived from the longitudinal dielectric permittivity of the dusty plasma, has been studied by kinetic theory. The results show that the P value, which describes the relative charge density on the dust in the plasma, and the charging frequency of a dust particle Ωc, which describes the ratio of charge changing of the dust particles, determine the character of the charge density fluctuation of low frequency. For a dusty plasma of P<<1, when the charging frequency Ωc is much smaller than the dusty plasma frequency wd, there is a strong charge density fluctuation which is of character of dust acoustic eigen wave. For a dusty plasma of P>>1, when the frequency Ωc, is much larger than wd there are weaker fluctuations with a wide spectrum. The results have been applied to the ionosphere and the range of radius and density of dust particles is found, where a strong charge density fluctuation of low frequency should exist.

  16. The relative validity and reproducibility of an iron food frequency questionnaire for identifying iron-related dietary patterns in young women.

    Science.gov (United States)

    Beck, Kathryn L; Kruger, Rozanne; Conlon, Cathryn A; Heath, Anne-Louise M; Coad, Jane; Matthys, Christophe; Jones, Beatrix; Stonehouse, Welma

    2012-08-01

    Using food frequency data to identify dietary patterns is a newly emerging approach to assessing the relationship between dietary intake and iron status. Food frequency questionnaires should be assessed for validity and reproducibility before use. We aimed to investigate the relative validity and reproducibility of an iron food frequency questionnaire (FeFFQ) specifically designed to identify iron-related dietary patterns. Participants completed the FeFFQ at baseline (FeFFQ1) and 1 month later (FeFFQ2) to assess reproducibility. A 4-day weighed diet record (4DDR) was completed between these assessments to determine validity. Foods appearing in the 4DDR were classified into the same 144 food groupings as the FeFFQ. Factor analysis was used to determine dietary patterns from FeFFQ1, FeFFQ2, and the 4DDR. A convenience sample of women (n=115) aged 18 to 44 years living in Auckland, New Zealand, during 2009. Agreement between diet pattern scores was compared using correlation coefficients, Bland-Altman analysis, cross-classification, and the weighted κ statistic. A "healthy" and a "sandwich and drinks" dietary pattern were identified from all three dietary assessments. Correlation coefficients between FeFFQ1 and the 4DDR diet pattern scores (validity) were 0.34 for the healthy, and 0.62 for the sandwich and drinks pattern (both Ps50% of participants into the correct tertile and <10% into the opposite tertile for both the healthy and sandwich and drinks diet pattern scores when compared with the 4DDR and FeFFQ2. The FeFFQ appears to be a reproducible and relatively valid method for identifying dietary patterns, and could be used to investigate the relationship between dietary patterns and iron status. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  17. Metrix Matrix: A Cloud-Based System for Tracking Non-Relative Value Unit Value-Added Work Metrics.

    Science.gov (United States)

    Kovacs, Mark D; Sheafor, Douglas H; Thacker, Paul G; Hardie, Andrew D; Costello, Philip

    2018-03-01

    In the era of value-based medicine, it will become increasingly important for radiologists to provide metrics that demonstrate their value beyond clinical productivity. In this article the authors describe their institution's development of an easy-to-use system for tracking value-added but non-relative value unit (RVU)-based activities. Metrix Matrix is an efficient cloud-based system for tracking value-added work. A password-protected home page contains links to web-based forms created using Google Forms, with collected data populating Google Sheets spreadsheets. Value-added work metrics selected for tracking included interdisciplinary conferences, hospital committee meetings, consulting on nonbilled outside studies, and practice-based quality improvement. Over a period of 4 months, value-added work data were collected for all clinical attending faculty members in a university-based radiology department (n = 39). Time required for data entry was analyzed for 2 faculty members over the same time period. Thirty-nine faculty members (equivalent to 36.4 full-time equivalents) reported a total of 1,223.5 hours of value-added work time (VAWT). A formula was used to calculate "value-added RVUs" (vRVUs) from VAWT. VAWT amounted to 5,793.6 vRVUs or 6.0% of total work performed (vRVUs plus work RVUs [wRVUs]). Were vRVUs considered equivalent to wRVUs for staffing purposes, this would require an additional 2.3 full-time equivalents, on the basis of average wRVU calculations. Mean data entry time was 56.1 seconds per day per faculty member. As health care reimbursement evolves with an emphasis on value-based medicine, it is imperative that radiologists demonstrate the value they add to patient care beyond wRVUs. This free and easy-to-use cloud-based system allows the efficient quantification of value-added work activities. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. Comparison of Optimal Portfolios Selected by Multicriterial Model Using Absolute and Relative Criteria Values

    Directory of Open Access Journals (Sweden)

    Branka Marasović

    2009-03-01

    Full Text Available In this paper we select an optimal portfolio on the Croatian capital market by using the multicriterial programming. In accordance with the modern portfolio theory maximisation of returns at minimal risk should be the investment goal of any successful investor. However, contrary to the expectations of the modern portfolio theory, the tests carried out on a number of financial markets reveal the existence of other indicators important in portfolio selection. Considering the importance of variables other than return and risk, selection of the optimal portfolio becomes a multicriterial problem which should be solved by using the appropriate techniques.In order to select an optimal portfolio, absolute values of criteria, like return, risk, price to earning value ratio (P/E, price to book value ratio (P/B and price to sale value ratio (P/S are included in our multicriterial model. However the problem might occur as the mean values of some criteria are significantly different for different sectors and because financial managers emphasize that comparison of the same criteria for different sectors could lead us to wrong conclusions. In the second part of the paper, relative values of previously stated criteria (in relation to mean value of sector are included in model for selecting optimal portfolio. Furthermore, the paper shows that if relative values of criteria are included in multicriterial model for selecting optimal portfolio, return in subsequent period is considerably higher than if absolute values of the same criteria were used.

  19. Fundamental frequency characteristics of Jordanian Arabic speakers.

    Science.gov (United States)

    Natour, Yaser S; Wingate, Judith M

    2009-09-01

    This study is the first in a series of investigations designed to test the acoustic characteristics of the normal Arabic voice. The subjects were three hundred normal Jordanian Arabic speakers (100 adult males, 100 adult females, and 100 children). The subjects produced a sustained phonation of the vowel /a:/ and stated their complete names (i.e. first, second, third and surname) using a carrier phrase. The samples were analyzed using the Multi Dimensional Voice Program (MDVP). Fundamental frequency (F0) from the /a:/ and speaking fundamental frequency (SF0) from the sentence were analyzed. Results revealed a significant difference of both F0 and SF0 values among adult Jordanian Arabic-speaking males (F0=131.34Hz +/- 18.65, SF0=137.45 +/- 18.93), females (F0=231.13Hz +/- 20.86, SF0=230.84 +/- 16.50) and children (F0=270.93Hz +/- 20.01, SF0=278.04 +/- 32.07). Comparison with other ethnicities indicated that F0 values of adult Jordanian Arabic-speaking males and females are generally consistent with adult Caucasian and African-American values. However, for Jordanian Arabic-speaking children, a higher trend in F0 values was present than their Western counterparts. SF0 values for adult Jordanian Arabic-speaking males are generally consistent with the adult Caucasian male SF0 values. However, SF0 values of adult Jordanian-speaking females and children were relatively higher than the reported Western values. It is recommended that speech-language pathologists in Arabic-speaking countries, Jordan in specific, utilize the new data provided (F0 and SF0) when evaluating and/or treating Arabic-speaking patients. Due to its cross-linguistic variability, SF0 emerged as a preferred measurement when conducting cross-cultural comparisons of voice features.

  20. Dynamic divisive normalization predicts time-varying value coding in decision-related circuits.

    Science.gov (United States)

    Louie, Kenway; LoFaro, Thomas; Webb, Ryan; Glimcher, Paul W

    2014-11-26

    Normalization is a widespread neural computation, mediating divisive gain control in sensory processing and implementing a context-dependent value code in decision-related frontal and parietal cortices. Although decision-making is a dynamic process with complex temporal characteristics, most models of normalization are time-independent and little is known about the dynamic interaction of normalization and choice. Here, we show that a simple differential equation model of normalization explains the characteristic phasic-sustained pattern of cortical decision activity and predicts specific normalization dynamics: value coding during initial transients, time-varying value modulation, and delayed onset of contextual information. Empirically, we observe these predicted dynamics in saccade-related neurons in monkey lateral intraparietal cortex. Furthermore, such models naturally incorporate a time-weighted average of past activity, implementing an intrinsic reference-dependence in value coding. These results suggest that a single network mechanism can explain both transient and sustained decision activity, emphasizing the importance of a dynamic view of normalization in neural coding. Copyright © 2014 the authors 0270-6474/14/3416046-12$15.00/0.

  1. Seismic isolation systems designed with distinct multiple frequencies

    International Nuclear Information System (INIS)

    Wu, Ting-shu; Seidensticker, R.W.

    1991-01-01

    Two systems for seismic base isolation are presented. The main feature of these system is that, instead of only one isolation frequency as in conventional isolation systems, they are designed to have two distinct isolation frequencies. When the responses during an earthquake exceed the design value(s), the system will automatically and passively shift to the secondly isolation frequency. Responses of these two systems to different ground motions including a harmonic motion with frequency same as the primary isolation frequency, show that no excessive amplification will occur. Adoption of these new systems certainly will greatly enhance the safety and reliability of an isolated superstructure against future strong earthquakes. 3 refs

  2. Probative value of absolute and relative judgments in eyewitness identification.

    Science.gov (United States)

    Clark, Steven E; Erickson, Michael A; Breneman, Jesse

    2011-10-01

    It is well-accepted that eyewitness identification decisions based on relative judgments are less accurate than identification decisions based on absolute judgments. However, the theoretical foundation for this view has not been established. In this study relative and absolute judgments were compared through simulations of the WITNESS model (Clark, Appl Cogn Psychol 17:629-654, 2003) to address the question: Do suspect identifications based on absolute judgments have higher probative value than suspect identifications based on relative judgments? Simulations of the WITNESS model showed a consistent advantage for absolute judgments over relative judgments for suspect-matched lineups. However, simulations of same-foils lineups showed a complex interaction based on the accuracy of memory and the similarity relationships among lineup members.

  3. Observation of frequency cutoff for self-excited dust acoustic waves

    Science.gov (United States)

    Nosenko, V.; Zhdanov, S. K.; Morfill, G. E.; Kim, S.-H.; Heinrich, J.; Merlino, R. L.

    2009-11-01

    Complex (dusty) plasmas consist of fine solid particles suspended in a weakly ionized gas. Complex plasmas are excellent model systems to study wave phenomena down to the level of individual ``atoms''. Spontaneously excited dust acoustic waves were observed with high temporal resolution in a suspension of micron-size kaolin particles in a dc discharge in argon. Wave activity was found at frequencies as high as 400 Hz. At high wave numbers, the wave dispersion relation was acoustic-like (frequency proportional to wave number). At low wave numbers, the wave frequency did not tend to zero, but reached a cutoff frequency fc instead. The value of fc declined with distance from the anode. We propose a simple model that explains the observed cutoff by particle confinement in plasma. The existence of a cutoff frequency is very important for the propagation of waves: the waves excited above fc are propagating, and those below fc are evanescent.

  4. A free-boundary value problem related to auto ignition of ...

    African Journals Online (AJOL)

    We examine a free boundary value problem related to auto ignition of combustible fluid in insulation materials. The criteria for the existence of similarity solution of the model equations are established. The conditions for the existence of unique solution are also stated. The numerical results which show the influence of ...

  5. Natural frequency analysis of fluid conveying pipeline with different boundary conditions

    International Nuclear Information System (INIS)

    Huang Yimin; Liu Yongshou; Li Baohui; Li Yanjiang; Yue Zhufeng

    2010-01-01

    In this study, the natural frequency of fluid-structure interaction in pipeline conveying fluid is investigated by eliminated element-Galerkin method, and the natural frequency equations with different boundary conditions are obtained. Furthermore, the expressions of first natural frequency are simplified in the case of different boundary conditions. Taking into account the Coriolis force, as an example, the natural frequency of a straight pipe simply supported at both ends is studied. In a given boundary condition, the four components (mass, stiffness, length and flow velocity) which relate to the natural frequency of pipeline conveying fluid are studied in detail and the results indicate that the effect of Coriolis force on natural frequency is inappreciable. Then the relationship between natural frequency of the pipeline conveying fluid and that of Euler beam is analyzed. Finally, a dimensionless flow velocity and limit values are presented, and they can be used to estimate the effect of the flow velocity on natural frequency. All the conclusions are well suited to nuclear plant and other industry fields.

  6. Prospect theory does not describe the feedback-related negativity value function.

    Science.gov (United States)

    Sambrook, Thomas D; Roser, Matthew; Goslin, Jeremy

    2012-12-01

    Humans handle uncertainty poorly. Prospect theory accounts for this with a value function in which possible losses are overweighted compared to possible gains, and the marginal utility of rewards decreases with size. fMRI studies have explored the neural basis of this value function. A separate body of research claims that prediction errors are calculated by midbrain dopamine neurons. We investigated whether the prospect theoretic effects shown in behavioral and fMRI studies were present in midbrain prediction error coding by using the feedback-related negativity, an ERP component believed to reflect midbrain prediction errors. Participants' stated satisfaction with outcomes followed prospect theory but their feedback-related negativity did not, instead showing no effect of marginal utility and greater sensitivity to potential gains than losses. Copyright © 2012 Society for Psychophysiological Research.

  7. Towards a Unified Understanding of Event-Related Changes in the EEG: The Firefly Model of Synchronization through Cross-Frequency Phase Modulation

    Science.gov (United States)

    Burgess, Adrian P.

    2012-01-01

    Although event-related potentials (ERPs) are widely used to study sensory, perceptual and cognitive processes, it remains unknown whether they are phase-locked signals superimposed upon the ongoing electroencephalogram (EEG) or result from phase-alignment of the EEG. Previous attempts to discriminate between these hypotheses have been unsuccessful but here a new test is presented based on the prediction that ERPs generated by phase-alignment will be associated with event-related changes in frequency whereas evoked-ERPs will not. Using empirical mode decomposition (EMD), which allows measurement of narrow-band changes in the EEG without predefining frequency bands, evidence was found for transient frequency slowing in recognition memory ERPs but not in simulated data derived from the evoked model. Furthermore, the timing of phase-alignment was frequency dependent with the earliest alignment occurring at high frequencies. Based on these findings, the Firefly model was developed, which proposes that both evoked and induced power changes derive from frequency-dependent phase-alignment of the ongoing EEG. Simulated data derived from the Firefly model provided a close match with empirical data and the model was able to account for i) the shape and timing of ERPs at different scalp sites, ii) the event-related desynchronization in alpha and synchronization in theta, and iii) changes in the power density spectrum from the pre-stimulus baseline to the post-stimulus period. The Firefly Model, therefore, provides not only a unifying account of event-related changes in the EEG but also a possible mechanism for cross-frequency information processing. PMID:23049827

  8. Prefrontal and striatal activity related to values of objects and locations

    Directory of Open Access Journals (Sweden)

    Soyoun eKim

    2012-07-01

    Full Text Available The value of an object acquired by a particular action often determines the motivation to produce that action. Previous studies found neural signals related to the values of different objects or goods in the orbitofrontal cortex, while the values of outcomes expected from different actions are broadly represented in multiple brain areas implicated in movement planning. However, how the brain combines the values associated with various objects and the information about their locations is not known. In this study, we tested whether the neurons in the dorsolateral prefrontal cortex (DLPFC and striatum in rhesus monkeys might contribute to translating the value signals between multiple frames of reference. Monkeys were trained to perform an oculomotor intertemporal choice in which the color of a saccade target and the number of its surrounding dots signaled the magnitude of reward and its delay, respectively. In both DLPFC and striatum, temporally discounted values associated with specific target colors and locations were encoded by partially overlapping populations of neurons. In the DLPFC, the information about reward delays and temporally discounted values of rewards available from specific target locations emerged earlier than the corresponding signals for target colors. Similar results were reproduced by a simple network model built to compute temporally discounted values of rewards in different locations. Therefore, DLPFC might play an important role in estimating the values of different actions by combining the previously learned values of objects and their present locations.

  9. DNA repair gene polymorphisms in relation to chromosome aberration frequencies in retired radiation workers

    International Nuclear Information System (INIS)

    Wilding, Craig S.; Relton, Caroline L.; Rees, Gwen S.; Tarone, Robert E.; Whitehouse, Caroline A.; Tawn, E. Janet

    2005-01-01

    Polymorphic variation in DNA repair genes was examined in a group of retired workers from the British Nuclear Fuels plc facility at Sellafield in relation to previously determined translocation frequencies in peripheral blood lymphocytes. Variation at seven polymorphisms in four genes involved in the base excision repair (XRCC1 R194W, R399Q and a [AC] n microsatellite in the 3' UTR) and double strand break repair (XRCC3 T241M and a [AC] n microsatellite in intron 3 of XRCC3, XRCC4 I134T, and a GACTAn microsatellite located 120kb 5' of XRCC5) pathways was determined for 291 retired radiation workers who had received cumulative occupational external radiation doses of between 0 and 1873mSv. When the interaction between radiation dose and each DNA repair gene polymorphism was examined in relation to translocation frequency there was no evidence for any of the polymorphisms studied influencing the response to occupational exposure. A positive interaction observed between genotype (individuals with at least one allele >=20 repeat units) at a microsatellite locus in the XRCC3 gene and smoking status should be interpreted cautiously because interactions were investigated for seven polymorphisms and two exposures. Nonetheless, further research is warranted to examine whether this DNA repair gene variant might be associated with a sub-optimal repair response to smoking-induced DNA damage and hence an increased frequency of translocations

  10. A Novel Frequency Measurement Method Suitable for a Large Frequency Ratio Condition

    Institute of Scientific and Technical Information of China (English)

    ZHOU Wei; XUAN Zong-Qiang; YU Jian-Guo; WANG Hai; ZHOU Hui; LI Zhi-Qi

    2004-01-01

    @@ As for the obstacles to direct comparison between superhigh and lower frequencies, we accomplish the accurate comparison between low and microwave frequencies with the 105 ratios of the operating frequencies on the basis of phase comparison between the signals whose frequencies are related by an arbitrary integer. This method is simple and accurate, and will be widely used as a special frequency comparison approach.

  11. Teachers' Values Related to Sustainable Development in Polish and Latvian Secondary Schools

    Science.gov (United States)

    Switala, Eugeniusz

    2015-01-01

    The aim of the paper is to present the results of the research on highlighting values related to sustainable development in Poland and Latvia by secondary school teachers and to compare two models by the use of action research. The research is presented as a process of identifying values mainly from the point of view of social development which is…

  12. Values and attitudes related to career preference and performance in the surgical clerkship.

    Science.gov (United States)

    Linn, B S; Zeppa, R

    1982-10-01

    We investigated the values and attitudes of junior medical students in relation to career preference (particularly surgery), ward behavior, and cognitive performance in the surgical clerkship. Students choosing specialty surgery were more cynical and authoritarian than those selecting general surgery. Those choosing general surgery had more self-esteem, and along with those who selected specialty surgery, more intolerance for ambiguity than other students. None of the values or attitudes were associated with grades, but several were related to ward behavior as judged by faculty and house staff. Students who valued academic achievement more and independence and intellectualism less and those with more submissive authoritarian views and more ego strength were considered better ward performers. This raises the question of whether such values and attitudes should be reinforced in ward performance or whether such students are rated higher simply because they are less disruptive to busy ward routines.

  13. Does Social Value Orientation Theory Apply to Social Relations?

    Directory of Open Access Journals (Sweden)

    Patricia Danielle Lewis

    2017-03-01

    Full Text Available This research asks whether Social Value Orientations (SVOs apply to the social relations of exchange networks. SVO literature identifies three types of orientation to rational action, determined by how actors value outcomes to self and other. Only the individualist is the self-interested, rational actor previously seen in exchange networks. The prosocial actor seeks to maximize joint outcomes and equality whereas the competitor seeks to maximize differences between self and other. The competitor and individualist are frequently collapsed into a proself type. Whereas SVO research has focused on games and social dilemmas, this research places prosocials and proselfs in equal, weak, and strong power exchange structures. We show that, if SVO applies, the behaviors of proself and prosocial will be very different. Experimental results demonstrate, however, that prosocials’ actions in exchanges are indistinguishable from activities of proselfs.

  14. Demosaicking Based on Optimization and Projection in Different Frequency Bands

    Directory of Open Access Journals (Sweden)

    Omer OsamaA

    2008-01-01

    Full Text Available Abstract A fast and effective iterative demosaicking algorithm is described for reconstructing a full-color image from single-color filter array data. The missing color values are interpolated on the basis of optimization and projection in different frequency bands. A filter bank is used to decompose an initially interpolated image into low-frequency and high-frequency bands. In the low-frequency band, a quadratic cost function is minimized in accordance with the observation that the low-frequency components of chrominance slowly vary within an object region. In the high-frequency bands, the high-frequency components of the unknown values are projected onto the high-frequency components of the known values. Comparison of the proposed algorithm with seven state-of-the-art demosaicking algorithms showed that it outperforms all of them for 20 images on average in terms of objective quality and that it is competitive with them from the subjective quality and complexity points of view.

  15. [Clinical value of CT-guided high frequency-induced thermotherapy as a treatment for intrahepatic cholangiocarcinoma].

    Science.gov (United States)

    Fan, Wei-Jun; Zhang, Liang; Gu, Yang-Kui; Wang, Li-Gang; Ouyang, Yu-Shu

    2008-07-01

    To evaluate the therapeutic effect of CT-guided high frequency-induced thermotherapy (HiTT) for intrahepatic cholangiocarcinoma. Seventeen patients of intrahepatic cholangiocarcinoma with 21 lesions underwent comprehensive treatment with HiTT as the principle approach. As to the patients with obstructive jaundice, percutaneous trans-hepatic cholangial drainage (PTCD) or bile duct endoprosthesis placement was performed first to improve the liver function, then HiTT was performed; and patients without obstructive jaundice underwent CT-guided HiTT directly, 1-2 weeks later, chemotherapy was given for 4 - 6 courses. CT scan 1 week after HiTT showed a short-term achievement rate of 100% (17/17), and the single puncture in situ ablation rate was 76.1% (16/21). The average life span in the near future was 13.5 months. The adverse effects included topo-bleeding, pain after procedure, liver function damage, defervescence, etc. All the patients recovered after symptomatic treatment. The clinical value of CT-guided HiTT for intrahepatic cholangiocarcinoma is obvious.

  16. Work Socialization and Adolescents' Work-Related Values in Single-Mother African American Families

    Science.gov (United States)

    Toyokawa, Teru; McLoyd, Vonnie C.

    2013-01-01

    This study examined African American mothers' work socialization messages in relation to adolescents' work-related values. Moderation effects of mother-adolescent relation quality on the linkage between maternal socialization messages and adolescents' outcomes were also examined. Participants were 245 single African American mothers and their…

  17. Language-Related Values, Reading Amount, and Reading Comprehension in Students with Migration Backgrounds

    Science.gov (United States)

    El-Khechen, Wahiba; Ferdinand, Hanna D.; Steinmayr, Ricarda; McElvany, Nele

    2016-01-01

    Background: Although various studies on general language performance have investigated determinants of students' reading comprehension (e.g., reading amount), they have paid insufficient attention to how students perceive parental values influence their language-related values and behaviour--and, as a consequence, their performance. This is…

  18. Estimation of initiating event frequency for external flood events by extreme value theorem

    International Nuclear Information System (INIS)

    Chowdhury, Sourajyoti; Ganguly, Rimpi; Hari, Vibha

    2017-01-01

    External flood is an important common cause initiating event in nuclear power plants (NPPs). It may potentially lead to severe core damage (SCD) by first causing the failure of the systems required for maintaining the heat sinks and then by contributing to failures of engineered systems designed to mitigate such failures. The sample NPP taken here is twin 220 MWe Indian standard pressurized heavy water reactor (PHWR) situated inland. A comprehensive in-house Level-1 internal event PSA for full power had already been performed. External flood assessment was further conducted in area of external hazard risk assessment in response to post-Fukushima measures taken in nuclear industries. The present paper describes the methodology to calculate initiating event (IE) frequency for external flood events for the sample inland Indian NPP. General extreme value (GEV) theory based on maximum likelihood method (MLM) and order statistics approach (OSA) is used to analyse the rainfall data for the site. Thousand-year return level and necessary return periods for extreme rainfall are evaluated. These results along with plant-specific topographical calculations quantitatively establish that external flooding resulting from upstream dam break, river flooding and heavy rainfall (flash flood) would be unlikely for the sample NPP in consideration.

  19. The Relation between Parental Values and Parenting Behavior: A Test of the Kohn Hypothesis.

    Science.gov (United States)

    Luster, Tom; And Others

    1989-01-01

    Used data on 65 mother-infant dyads to test Kohn's hypothesis concerning the relation between values and parenting behavior. Findings support Kohn's hypothesis that parents who value self-direction would emphasize supportive function of parenting and parents who value conformity would emphasize their obligations to impose restraints. (Author/NB)

  20. Enhancing the accuracy of GPS point positioning by converting the single frequency data to dual frequency data

    Directory of Open Access Journals (Sweden)

    Aly M. El-naggar

    2011-09-01

    Full Text Available The global positioning system (GPS has been used to support a wide variety of applications, such as high-accuracy positioning and navigation. Differential GPS techniques can largely eliminate common-mode errors between the reference and the rover GPS stations resulting from ionospheric and tropospheric refraction and delays, satellite and receiver clock biases, and orbital errors [1]. The ionospheric delay in the propagation of global positioning system (GPS signals is one of the main sources of error in GPS precise positioning and navigation. A dual-frequency GPS receiver can eliminate (to the first order the ionospheric delay through a linear combination of the L1 and L2 observations [2]. The most significant effect of ionospheric delay appear in case of using single frequency data. In this paper the single frequency data of concerned station are converted to dual frequency data by employing dual frequency data from 11 regional GPS stations distributed around it. Total electron content (TEC was calculated at every GPS station to produce the mathematical model of TEC which is a function of latitude (Φ and longitude (λ. By using this mathematical model the values of TEC and L2 can be predicted at the single frequency GPS station for each satellite, after that the comparison between predicted and observation values of TEC and L2 was performed. The estimation method and test results of the proposed method indicates that the difference between predicted and observation values is very small.

  1. On a covariant 2+2 formulation of the initial value problem in general relativity

    International Nuclear Information System (INIS)

    Smallwood, J.

    1980-03-01

    The initial value problems in general relativity are considered from a geometrical standpoint with especial reference to the development of a covariant 2+2 formalism in which space-time is foliated by space-like 2-surfaces under the headings; the Cauchy problem in general relativity, the covariant 3+1 formulation of the Cauchy problem, characteristic and mixed initial value problems, on locally imbedding a family of null hypersurfaces, the 2+2 formalism, the 2+2 formulation of the Cauchy problem, the 2+2 formulation of the characteristic and mixed initial value problems, and a covariant Lagrangian 2+2 formulation. (U.K.)

  2. The value of service reliability

    OpenAIRE

    Benezech , Vincent; Coulombel , Nicolas

    2013-01-01

    International audience; This paper studies the impact of service frequency and reliability on the choice of departure time and the travel cost of transit users. When the user has (α, β, γ) scheduling preferences, we show that the optimal head start decreases with service reliability, as expected. It does not necessarily decrease with service frequency, however. We derive the value of service headway (VoSH) and the value of service reliability (VoSR), which measure the marginal effect on the e...

  3. Low frequency electric and magnetic fields

    Science.gov (United States)

    Spaniol, Craig

    1989-01-01

    Following preliminary investigations of the low frequency electric and magnetic fields that may exists in the Earth-ionospheric cavity, measurements were taken with state-of-the art spectrum analyzers. As a follow up to this activity, an investigation was initiated to determine sources and values for possible low frequency signal that would appear in the cavity. The lowest cavity resonance is estimated at about 8 Hz, but lower frequencies may be an important component of our electromagnetic environment. The potential field frequencies produced by the electron were investigated by a classical model that included possible cross coupling of the electric and gravitation fields. During this work, an interesting relationship was found that related the high frequency charge field with the extremely low frequency of the gravitation field. The results of numerical calculations were surprisingly accurate and this area of investigation is continuing. The work toward continued development of a standardized monitoring facility is continuing with the potential of installing the prototype at West Virginia State College early in 1990. This installation would be capable of real time monitoring of ELF signals in the Earth-ionoshpere cavity and would provide some directional information. A high gain, low noise, 1/f frequency corrected preamplifier was designed and tested for the ferrite core magnetic sensor. The potential application of a super conducting sensor for the ELF magnetic field detection is under investigation. It is hoped that a fully operational monitoring network could pinpoint the location of ELF signal sources and provide new information on where these signals originate and what causes them, assuming that they are natural in origin.

  4. Extraction of repetitive transients with frequency domain multipoint kurtosis for bearing fault diagnosis

    Science.gov (United States)

    Liao, Yuhe; Sun, Peng; Wang, Baoxiang; Qu, Lei

    2018-05-01

    The appearance of repetitive transients in a vibration signal is one typical feature of faulty rolling element bearings. However, accurate extraction of these fault-related characteristic components has always been a challenging task, especially when there is interference from large amplitude impulsive noises. A frequency domain multipoint kurtosis (FDMK)-based fault diagnosis method is proposed in this paper. The multipoint kurtosis is redefined in the frequency domain and the computational accuracy is improved. An envelope autocorrelation function is also presented to estimate the fault characteristic frequency, which is used to set the frequency hunting zone of the FDMK. Then, the FDMK, instead of kurtosis, is utilized to generate a fast kurtogram and only the optimal band with maximum FDMK value is selected for envelope analysis. Negative interference from both large amplitude impulsive noise and shaft rotational speed related harmonic components are therefore greatly reduced. The analysis results of simulation and experimental data verify the capability and feasibility of this FDMK-based method

  5. The value of pulmonary vessel CT measuring and calculating of relative ratio

    International Nuclear Information System (INIS)

    Ji Jiansong; Xu Xiaoxiong; Lv Suzhen; Zhao Zhongwei; Wang Zufei; Xu Min; Gong Jianping

    2004-01-01

    Objective: To evaluate value of CT measurement and calculation of vessels of isolate pig lung, by compare with measurement and calculation of resin cast of them. Methods: CT scanned and measured the four isolated pig lung which vessels were full with ABS liquid or self-solidification resin liquid, and calculate the relative ratio of superior/inferior order and vein/artery of same order. After resin cast were made, measure and calculate the same as CT did. Results: Second order of calculation of vein/artery of same order by the two method had statistic difference (P 0.05). Conclusion: CT has high value in calculation of the relative ratio of superior/inferior order

  6. Relations between elliptic multiple zeta values and a special derivation algebra

    International Nuclear Information System (INIS)

    Broedel, Johannes; Matthes, Nils; Schlotterer, Oliver

    2016-01-01

    We investigate relations between elliptic multiple zeta values (eMZVs) and describe a method to derive the number of indecomposable elements of given weight and length. Our method is based on representing eMZVs as iterated integrals over Eisenstein series and exploiting the connection with a special derivation algebra. Its commutator relations give rise to constraints on the iterated integrals over Eisenstein series relevant for eMZVs and thereby allow to count the indecomposable representatives. Conversely, the above connection suggests apparently new relations in the derivation algebra. Under https://tools.aei.mpg.de/emzv we provide relations for eMZVs over a wide range of weights and lengths. (paper)

  7. Relationship between wingbeat frequency and resonant frequency of the wing in insects

    International Nuclear Information System (INIS)

    Ha, Ngoc San; Truong, Quang Tri; Goo, Nam Seo; Park, Hoon Cheol

    2013-01-01

    In this study, we experimentally studied the relationship between wingbeat frequency and resonant frequency of 30 individuals of eight insect species from five orders: Odonata (Sympetrum flaveolum), Lepidoptera (Pieris rapae, Plusia gamma and Ochlodes), Hymenoptera (Xylocopa pubescens and Bombus rupestric), Hemiptera (Tibicen linnei) and Coleoptera (Allomyrina dichotoma). The wingbeat frequency of free-flying insects was measured using a high-speed camera while the natural frequency was determined using a laser displacement sensor along with a Bruel and Kjaer fast Fourier transform analyzer based on the base excitation method. The results showed that the wingbeat frequency was related to body mass (m) and forewing area (A f ), following the proportionality f ∼ m 1/2 /A f , while the natural frequency was significantly correlated with area density (f 0  ∼ m w /A f , m w is the wing mass). In addition, from the comparison of wingbeat frequency to natural frequency, the ratio between wingbeat frequency and natural frequency was found to be, in general, between 0.13 and 0.67 for the insects flapping at a lower wingbeat frequency (less than 100 Hz) and higher than 1.22 for the insects flapping at a higher wingbeat frequency (higher than 100 Hz). These results suggest that wingbeat frequency does not have a strong relation with resonance frequency: in other words, insects have not been evolved sufficiently to flap at their wings' structural resonant frequency. This contradicts the general conclusion of other reports-–that insects flap at their wings' resonant frequency to take advantage of passive deformation to save energy. (paper)

  8. The relative importance of geophysical constraints, amenity values, and farm-related factors in the dynamics of grassland set-aside

    DEFF Research Database (Denmark)

    Odgaard, Mette Vestergaard; Moeslund, Jesper Erenskjold; Bøcher, Peder Klith

    2013-01-01

    This study aimed at quantifying the spatial distribution of set-aside – highly valuable biodiversity reservoirs – in a typical lowland agricultural region (Denmark), just before and after the set-aside policy change (years 2007 and 2008), to assess which factors drive farmers’ set-aside priorities......, and to elaborate the potential consequence of the set-aside spatial transformation from 2007 to 2008 on nature. Multiple regressions were used to test if and how set-aside is linked to three potential groups of drivers: (1) geophysical constraints (topographic and edaphic constraints on the farming......-suitability of an area), (2) amenity values (nature conservation and aesthetic values), and (3) farming-related factors (e.g., field size and livestock density). The spatial distribution of set-aside was influenced by both geophysical constraints and amenity values and only some extent farming-related factors. More...

  9. High frequency source localization in a shallow ocean sound channel using frequency difference matched field processing.

    Science.gov (United States)

    Worthmann, Brian M; Song, H C; Dowling, David R

    2015-12-01

    Matched field processing (MFP) is an established technique for source localization in known multipath acoustic environments. Unfortunately, in many situations, particularly those involving high frequency signals, imperfect knowledge of the actual propagation environment prevents accurate propagation modeling and source localization via MFP fails. For beamforming applications, this actual-to-model mismatch problem was mitigated through a frequency downshift, made possible by a nonlinear array-signal-processing technique called frequency difference beamforming [Abadi, Song, and Dowling (2012). J. Acoust. Soc. Am. 132, 3018-3029]. Here, this technique is extended to conventional (Bartlett) MFP using simulations and measurements from the 2011 Kauai Acoustic Communications MURI experiment (KAM11) to produce ambiguity surfaces at frequencies well below the signal bandwidth where the detrimental effects of mismatch are reduced. Both the simulation and experimental results suggest that frequency difference MFP can be more robust against environmental mismatch than conventional MFP. In particular, signals of frequency 11.2 kHz-32.8 kHz were broadcast 3 km through a 106-m-deep shallow ocean sound channel to a sparse 16-element vertical receiving array. Frequency difference MFP unambiguously localized the source in several experimental data sets with average peak-to-side-lobe ratio of 0.9 dB, average absolute-value range error of 170 m, and average absolute-value depth error of 10 m.

  10. Variables relating to the allocation of pocket money to children: parental reasons and values.

    Science.gov (United States)

    Feather, N T

    1991-09-01

    This study was concerned with relations among parents' beliefs, values and practices in regard to the allocation of pocket money to their children. Mothers and fathers in 133 Adelaide families provided information about the pocket money allowance they gave to each child in their family and they completed items designed to measure the importance of various possible reasons for their allocations (family concern, independence training, child's needs), as well as items that assessed value dimensions (work ethic, social welfare, compassion). Results showed that social welfare values were associated with family concern reasons, and that individualistic work ethic values were associated with independence training reasons but were antagonistic to reasons concerned with meeting the child's needs. The amount of pocket money provided was positively related to both the age of the child and to the importance of family concern reasons. Parents saw independence training and meeting the child's needs as more important reasons for older children and mothers emphasized children's needs more than fathers. These results were discussed in relation to other research on distributive justice, allocation decisions, pocket money and household tasks.

  11. Nonelite exercise-related injuries: participant reported frequency, management and perceptions of their consequences.

    Science.gov (United States)

    Grice, A; Kingsbury, S R; Conaghan, P G

    2014-04-01

    This mixed methods study explored the frequency of sport/exercise-related injuries in nonelite sport, participant-reported management and perceptions of potential injury consequences. Focus group participants, who trained two to four times a week and had previously sustained musculoskeletal sports-related injuries, reported seeking medical advice secondary to advice from teammates or online research. General practitioners were viewed as gatekeepers to specialist secondary care and less able to effectively treat sport-related injuries. Participants displayed limited awareness of potential future implications of injury, and considered physical and psychological benefits of exercise more valuable than potential injury-associated risks. In the survey of physically active people, over half reported sustaining an exercise-related injury (562/1002, 56%). Previously injured respondents were less likely to consider consulting a health professional for injury-related advice than those with no injury history (45% vs 64%; P sports-related injuries and a lack of awareness about appropriate injury management and potential consequences of injury, particularly in the long-term. © 2013 The Authors. Scandinavian Journal of Medicine & Science in Sports published by John Wiley & Sons Ltd.

  12. CONVERGENCES AND DIVERGENCES RELATED TO FAIR VALUE

    OpenAIRE

    Ionica Oncioiu; Florin Razvan Oncioiu; Daniela Simona Nenciu

    2012-01-01

    Many authors present the advantages of fair value accounting, but others contest this concept, because of its volatility and subjective tendency of the models used for the evaluation. The advantages of fair value include utility, relevance, transparency and superior accuracy of the results, provides more clarity to the financial statements, it provides a total accounting of the comparable value and it gives more liability to the manager. However, critics of fair value accounting do not provid...

  13. The Role of Parental Perceptions of Tic Frequency and Intensity in Predicting Tic-Related Functional Impairment in Youth with Chronic Tic Disorders

    Science.gov (United States)

    Espil, Flint M.; Capriotti, Matthew R.; Conelea, Christine A.; Woods, Douglas W.

    2014-01-01

    Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with Chronic Tic Disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic frequency and intensity predicted tic-related impairment in several areas; including family and peer relationships, school interference, and social endeavors, even when controlling for the presence of comorbid anxiety symptoms and Attention Deficit Hyperactivity Disorder diagnostic status. Results showed that tic intensity predicted more variance across more domains than tic frequency. PMID:24395287

  14. The role of parental perceptions of tic frequency and intensity in predicting tic-related functional impairment in youth with chronic tic disorders.

    Science.gov (United States)

    Espil, Flint M; Capriotti, Matthew R; Conelea, Christine A; Woods, Douglas W

    2014-12-01

    Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with chronic tic disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic frequency and intensity predicted tic-related impairment in several areas; including family and peer relationships, school interference, and social endeavors, even when controlling for the presence of comorbid anxiety symptoms and Attention Deficit Hyperactivity Disorder diagnostic status. Results showed that tic intensity predicted more variance across more domains than tic frequency.

  15. Frequency of referral of patients with safety-related contraindications to magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dewey, Marc [Departments of Radiology, Charite, Medical School, Humboldt-Universitaet zu Berlin (Germany)]. E-mail: marc.dewey@charite.de; Schink, Tania [Medical Biometry, Charite, Medical School, Humboldt-Universitaet zu Berlin (Germany)]. E-mail: tania.schink@charite.de; Dewey, Charles F. [Radiology, Outpatient Centre Loebau, Poststr. 20, 02738 Loebau (Germany)]. E-mail: dewey@t-online.de

    2007-07-15

    Purpose: To analyse the frequency of patients with absolute and relative contraindications to magnetic resonance (MR) imaging who were actually referred to an outpatient imaging centre for an MR examination Materials and methods: Altogether a total of 51,547 consecutive patients were included between November 1997 and December 2005. Reasons preventing MR imaging were classified into the following categories: absolute and relative contraindications. Results: The referral frequency of patients with absolute contraindications to MR imaging was 0.41% (211 of 51,547 patients; 95% CI, 0.36-0.47%). The absolute contraindications were shrapnels located in biologically sensitive areas (121 patients, 0.23%; 95% CI, 0.20-0.28%), cardiac pacemakers (42 patients, 0.08%; 95% CI, 0.06-0.11%), and other unsafe implants (48 patients, 0.09%; 95% CI, 0.07-0.12%). Also patients with a relative contraindication to MR imaging were referred such as women with a first-trimester pregnancy (13 patients, 0.03%; 95% CI, 0.01-0.04%). Conclusion: Surprisingly, a considerable number of patients (0.41%) with cardiac pacemakers, other metallic implants (not approved for MR), or shrapnels are referred to MR facilities despite the well-known recommendations not to examine such patients. Thus, absolute contraindications to MR imaging are commonly found among patients referred for MR examinations and every effort needs to be made to screen patients prior to MR imaging for such contraindications to avoid detrimental results. Also, institutions placing implants (approved and unapproved for MR) should become legally responsible for providing the required information to the patients and their physicians.

  16. Frequency of referral of patients with safety-related contraindications to magnetic resonance imaging

    International Nuclear Information System (INIS)

    Dewey, Marc; Schink, Tania; Dewey, Charles F.

    2007-01-01

    Purpose: To analyse the frequency of patients with absolute and relative contraindications to magnetic resonance (MR) imaging who were actually referred to an outpatient imaging centre for an MR examination Materials and methods: Altogether a total of 51,547 consecutive patients were included between November 1997 and December 2005. Reasons preventing MR imaging were classified into the following categories: absolute and relative contraindications. Results: The referral frequency of patients with absolute contraindications to MR imaging was 0.41% (211 of 51,547 patients; 95% CI, 0.36-0.47%). The absolute contraindications were shrapnels located in biologically sensitive areas (121 patients, 0.23%; 95% CI, 0.20-0.28%), cardiac pacemakers (42 patients, 0.08%; 95% CI, 0.06-0.11%), and other unsafe implants (48 patients, 0.09%; 95% CI, 0.07-0.12%). Also patients with a relative contraindication to MR imaging were referred such as women with a first-trimester pregnancy (13 patients, 0.03%; 95% CI, 0.01-0.04%). Conclusion: Surprisingly, a considerable number of patients (0.41%) with cardiac pacemakers, other metallic implants (not approved for MR), or shrapnels are referred to MR facilities despite the well-known recommendations not to examine such patients. Thus, absolute contraindications to MR imaging are commonly found among patients referred for MR examinations and every effort needs to be made to screen patients prior to MR imaging for such contraindications to avoid detrimental results. Also, institutions placing implants (approved and unapproved for MR) should become legally responsible for providing the required information to the patients and their physicians

  17. Meal frequency patterns and glycemic properties of maternal diet in relation to preterm delivery: Results from a large prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Linda Englund-Ögge

    Full Text Available Dietary habits are linked to high maternal glucose levels, associated with preterm delivery. The aim of this study was to examine the associations between meal frequency and glycemic properties of maternal diet in relation to preterm delivery.This prospective cohort study included 66,000 women from the Norwegian Mother and Child Cohort Study (MoBa. Meal frequency and food intake data were obtained from a validated food frequency questionnaire during mid-pregnancy. Principal component factor analysis was used with a data-driven approach, and three meal frequency patterns were identified: "snack meal", "main meal", and "evening meal". Pattern scores were ranked in quartiles. Glycemic index and glycemic load were estimated from table values. Intakes of carbohydrates, added sugar, and fiber were reported in grams per day and divided into quartiles. Gestational age was obtained from the Medical Birth Registry of Norway. Preterm delivery was defined as birth at <37 gestational weeks. A Cox regression model was used to assess associations with preterm delivery.After adjustments, the "main meal" pattern was associated with a reduced risk of preterm delivery, with hazard ratios (HRs of 0.89 (95% confidence interval (CI: 0.80, 0.98 and 0.90 (95% CI: 0.81, 0.99 for the third and fourth quartiles, respectively, and p for trend of 0.028. This was mainly attributed to the group of women with BMI ≥25 kg/m2, with HRs of 0.87 (95% CI: 0.79, 0.96 and 0.89 (95% CI: 0.80, 0.98 for the third and fourth quartiles, respectively, and p for trend of 0.010. There was no association between glycemic index, glycemic load, carbohydrates, added sugar, fiber, or the remaining meal frequency patterns and preterm delivery.Regular consumption of main meals (breakfast, lunch, dinner was associated with a lower risk of preterm delivery. Diet should be further studied as potential contributing factors for preterm delivery.

  18. Reinforcing value and hypothetical behavioral economic demand for food and their relation to BMI.

    Science.gov (United States)

    Epstein, Leonard H; Paluch, Rocco A; Carr, Katelyn A; Temple, Jennifer L; Bickel, Warren K; MacKillop, James

    2018-04-01

    Food is a primary reinforcer, and food reinforcement is related to obesity. The reinforcing value of food can be measured by establishing how hard someone will work to get food on progressive-ratio schedules. An alternative way to measure food reinforcement is a hypothetical purchase task which creates behavioral economic demand curves. This paper studies whether reinforcing value and hypothetical behavioral demand approaches are assessing the same or unique aspects of food reinforcement for low (LED) and high (HED) energy density foods using a combination of analytic approaches in females of varying BMI. Results showed absolute reinforcing value for LED and HED foods and relative reinforcing value were related to demand intensity (r's = 0.20-0.30, p's demand elasticity (r's = 0.17-0.22, p's demand task, and the differential role of effort in the two tasks. Examples of how a better understanding of food reinforcement may be useful to prevent or treat obesity are discussed, including engaging in alternative non-food reinforcers as substitutes for food, such as crafts or socializing in a non-food environment, and reducing the value of immediate food reinforcers by episodic future thinking. Copyright © 2018. Published by Elsevier Ltd.

  19. Conformal changes of metrics and the initial-value problem of general relativity

    International Nuclear Information System (INIS)

    Mielke, E.W.

    1977-01-01

    Conformal techniques are reviewed with respect to applications to the initial-value problem of general relativity. Invariant transverse traceless decompositions of tensors, one of its main tools, are related to representations of the group of 'conformeomorphisms' acting on the space of all Riemannian metrics on M. Conformal vector fields, a kernel in the decomposition, are analyzed on compact manifolds with constant scalar curvature. The realization of arbitrary functions as scalar curvature of conformally equivalent metrics, a generalization of Yamabe's (Osaka Math. J.; 12:12 (1960)) conjecture, is applied to the Hamiltonian constraint and to the issue of positive energy of gravitational fields. Various approaches to the solution of the initial-value equations produced by altering the scaling behaviour of the second fundamental form are compared. (author)

  20. Breakfast frequency among adolescents

    DEFF Research Database (Denmark)

    Pedersen, Trine Pagh; Holstein, Bjørn E; Damsgaard, Mogens Trab

    2016-01-01

    OBJECTIVE: To investigate (i) associations between adolescents' frequency of breakfast and family functioning (close relations to parents, quality of family communication and family support) and (ii) if any observed associations between breakfast frequency and family functioning vary...... (n 3054) from a random sample of forty-one schools. RESULTS: Nearly one-quarter of the adolescents had low breakfast frequency. Low breakfast frequency was associated with low family functioning measured by three dimensions. The OR (95 % CI) of low breakfast frequency was 1·81 (1·40, 2......·33) for adolescents who reported no close relations to parents, 2·28 (1·61, 3·22) for adolescents who reported low level of quality of family communication and 2·09 (1·39, 3·15) for adolescents who reported low level of family support. Joint effect analyses suggested that the odds of low breakfast frequency among...

  1. Impact of Sterile Compounding Batch Frequency on Pharmaceutical Waste.

    Science.gov (United States)

    Abbasi, Ghalib; Gay, Evan

    2017-01-01

    Purpose: To measure the impact of increasing sterile compounding batch frequency on pharmaceutical waste as it relates to cost and quantity. Methods: Pharmaceutical IV waste at a tertiary care hospital was observed and recorded for 7 days. The batching frequency of compounded sterile products (CSPs) was then increased from twice daily to 4 times daily. After a washout period, pharmaceutical IV waste was then recorded for another 7 days. The quantity of units wasted and the cost were compared between both phases to determine the impact that batching frequency has on IV waste, specifically among high- and low-cost drugs. Results: Patient days increased from 2,459 during phase 1 to 2,617 during phase 2. The total number of CSPs wasted decreased from 3.6 to 2.7 doses per 100 patient days. Overall cost was reduced from $4,585.36 in phase 1 to $4,453.88 in phase 2. The value of wasted high-cost drugs per 100 patient days increased from $146 in phase 1 to $149 in phase 2 ( p > .05). The value of wasted low cost drugs per 100 patient days decreased from $41 in phase 1 to $21 in phase 2 ( p waste quantity and cost. The highest impact of the intervention was observed among low-cost CSPs.

  2. The Role of Human Values and Relations in the Employment of People with Work-Relevant Disabilities

    Directory of Open Access Journals (Sweden)

    Lieke Kuiper

    2016-11-01

    Full Text Available The aim of this study is to discuss the role of human values and relations in the employment of people with work-relevant disabilities. Purpose: Finding and maintaining a paid job is known to be more difficult for people with a disability. The aim of the study is to explore the use which people with a disability make of their private and professional network in finding and maintaining a paid job and the role values play in these relations. This was placed in the context of three complementary perspectives: a perspective that stresses the importance of other than merely rationalistic values, a perspective that stresses the importance of values in work and an interpersonal perspective in which ‘the Other’ is central. Methods: Semi-structured interviews were held with 8 people with a working disability. As well, 4 interviews were held with people from their private network (family and partner and 4 interviews with people from their professional network (colleagues and employers. All interviews were audio-taped and transcribed verbatim. A framework analysis was used to identify the different values in the interviews. This was done with use of MAXqda. Results: The interviews showed that both romantic and rational values and arguments were mentioned by the employers in the context of hiring people with a work-relevant disability; they need to be willing to adjust. The importance of human relations was emphasised in the values mentioned by the respondents when talking about having a paid job. Moreover, ‘the Other’ played an important role in the employment process of people with a work-relevant disability. People with such a disability asked their private network to help them and to provide emotional support. Conclusion: Enabling values and relations had more chance if they were in line with the mission and central value of the organisation. This was one of the first studies on the role that human values and relations play in maintaining a paid

  3. Reliability and applications of statistical methods based on oligonucleotide frequencies in bacterial and archaeal genomes

    DEFF Research Database (Denmark)

    Bohlin, J; Skjerve, E; Ussery, David

    2008-01-01

    with here are mainly used to examine similarities between archaeal and bacterial DNA from different genomes. These methods compare observed genomic frequencies of fixed-sized oligonucleotides with expected values, which can be determined by genomic nucleotide content, smaller oligonucleotide frequencies......, or be based on specific statistical distributions. Advantages with these statistical methods include measurements of phylogenetic relationship with relatively small pieces of DNA sampled from almost anywhere within genomes, detection of foreign/conserved DNA, and homology searches. Our aim was to explore...... the reliability and best suited applications for some popular methods, which include relative oligonucleotide frequencies (ROF), di- to hexanucleotide zero'th order Markov methods (ZOM) and 2.order Markov chain Method (MCM). Tests were performed on distant homology searches with large DNA sequences, detection...

  4. Resonant magnetic pumping at very low frequency

    International Nuclear Information System (INIS)

    Canobbio, Ernesto

    1978-01-01

    We propose to exploit for plasma heating purposes the very low frequency limit of the Alfven wave resonance condition, which reduces essentially to safety factor q=m/n, a rational number. It is shown that a substantial fraction of the total RF-energy can be absorbed by the plasma. The lowest possible frequency value is determined by the maximum tolerable width of the RF-magnetic islands which develop near the singular surface. The obvious interest of the proposed scheme is the low frequency value (f<=10 KHz) which allows the RF-coils to be protected by stainless steel or even to be put outside the liner

  5. A Multiple Criteria Decision Making Method Based on Relative Value Distances

    Directory of Open Access Journals (Sweden)

    Shyur Huan-jyh

    2015-12-01

    Full Text Available This paper proposes a new multiple criteria decision-making method called ERVD (election based on relative value distances. The s-shape value function is adopted to replace the expected utility function to describe the risk-averse and risk-seeking behavior of decision makers. Comparisons and experiments contrasting with the TOPSIS (Technique for Order Preference by Similarity to the Ideal Solution method are carried out to verify the feasibility of using the proposed method to represent the decision makers’ preference in the decision making process. Our experimental results show that the proposed approach is an appropriate and effective MCDM method.

  6. Voluntary movement frequencies in submaximal one- and two-legged knee extension exercise and pedaling

    Directory of Open Access Journals (Sweden)

    Julie Sørbø Stang

    2016-02-01

    Full Text Available Understanding of behavior and control of human voluntary rhythmic stereotyped leg movements is useful in work to improve performance, function, and rehabilitation of exercising, healthy, and injured humans. The present study aimed at adding to the existing understanding within this field. To pursue the aim, correlations between freely chosen movement frequencies in relatively simple, single-joint, one- and two-legged knee extension exercise were investigated. The same was done for more complex, multiple-joint, one- and two-legged pedaling. These particular activities were chosen because they could be considered related to some extent, as they shared a key aspect of knee extension, and because they at the same time were different. The activities were performed at submaximal intensities, by healthy individuals (n=16, thereof 8 women; 23.4±2.7 years; 1.70±0.11 m; 68.6±11.2 kg.High and fair correlations (R-values of 0.99 and 0.75 occurred between frequencies generated with the dominant leg and the nondominant leg during knee extension exercise and pedaling, respectively. Fair to high correlations (R-values between 0.71 and 0.95 occurred between frequencies performed with each of the two legs in an activity, and the two-legged frequency performed in the same type of activity. In general, the correlations were higher for knee extension exercise than for pedaling. Correlations between knee extension and pedaling frequencies were of modest occurrence.The correlations between movement frequencies generated separately by each of the legs might be interpreted to support the following working hypothesis, which was based on existing literature. It is likely that involved central pattern generators (CPGs of the two legs share a common frequency generator or that separate frequency generators of each leg are attuned via interneuronal connections. Further, activity type appeared to be relevant. Thus, the apparent common rhythmogenesis for the two legs

  7. Human frequency-following response to speech-like sounds: correlates of off-frequency masking.

    Science.gov (United States)

    Krishnan, Ananthanarayan; Agrawal, Smita

    2010-01-01

    Off-frequency masking of the second formant by energy at the first formant has been shown to influence both identification and discrimination of the second formant in normal-hearing and hearing-impaired listeners. While both excitatory spread and two-tone suppression have been implicated in this simultaneous masking, their relative contribution has been shown to depend on both the level of the masker and the frequency separation between the probe and the masker. Off-frequency masking effects were evaluated in 10 normal-hearing human adults using the frequency-following response (FFR) to two two-tone approximations of vowel stimuli (/a/ and /u/). In the first experiment, the masking effect of F(1) on F(2) was evaluated by attenuating the level of F(1) relative to a fixed F(2) level. In the second experiment, the masking effect was evaluated by increasing the frequency separation between F(1) and F(2) using F(2) frequency as the variable. Results revealed that both attenuation of the F(1) level, and increasing the frequency separation between F(1) and F(2) increased the magnitude of the FFR component at F(2). These results are consistent with a release from off-frequency masking. Given that the results presented here are for high signal and masker levels and for relatively smaller frequency separation between the masker and the probe, it is possible that both suppression and excitatory spread contributed to the masking effects observed in our data. Copyright2009 S. Karger AG, Basel.

  8. The Familial Socialization of Culturally Related Values in Mexican American Families

    Science.gov (United States)

    Knight, George P.; Berkel, Cady; Umana-Taylor, Adriana J.; Gonzales, Nancy A.; Ettekal, Idean; Jaconis, Maryanne; Boyd, Brenna M.

    2011-01-01

    Research has documented a relation between parents' ethnic socialization and youth's ethnic identity, yet there has been little research examining the transmission of cultural values from parents to their children through ethnic socialization and ethnic identity. This study examines a prospective model in which mothers' and fathers' Mexican…

  9. Molecular-level mechanisms of vibrational frequency shifts in a polar liquid.

    Science.gov (United States)

    Morales, Christine M; Thompson, Ward H

    2011-06-16

    A molecular-level analysis of the origins of the vibrational frequency shifts of the CN stretching mode in neat liquid acetonitrile is presented. The frequency shifts and infrared spectrum are calculated using a perturbation theory approach within a molecular dynamics simulation and are in good agreement with measured values reported in the literature. The resulting instantaneous frequency of each nitrile group is decomposed into the contributions from each molecule in the liquid and by interaction type. This provides a detailed picture of the mechanisms of frequency shifts, including the number of surrounding molecules that contribute to the shift, the relationship between their position and relative contribution, and the roles of electrostatic and van der Waals interactions. These results provide insight into what information is contained in infrared (IR) and Raman spectra about the environment of the probed vibrational mode. © 2011 American Chemical Society

  10. Critical evaluation of analytical models for stochastic heating in dual-frequency capacitive discharges

    International Nuclear Information System (INIS)

    Sharma, S; Turner, M M

    2013-01-01

    Dual-frequency capacitive discharges are widespread in the semiconductor industry and are used, for example, in etching of semiconductor materials to manufacture microchips. In low-pressure dual radio-frequency capacitive discharges, stochastic heating is an important phenomenon. Recent theoretical work on this problem using several different approaches has produced results that are broadly in agreement insofar as scaling with the discharge parameters is concerned, but there remains some disagreement in detail concerning the absolute size of the effect for the case of dual-frequency capacitive discharges. In this work, we investigate the dependence of stochastic heating on various discharge parameters with the help of particle-in-cell (PIC) simulation. The dual-frequency analytical models are in fair agreement with PIC results for values of the low-frequency current density amplitude J lf (or dimensionless control parameter H lf ∼ 5) typical of many modern experiments. However, for higher values of J lf (or higher H lf ), new physical phenomena (like field reversal, reflection of ions, etc) appear and the simulation results deviate from existing dual-frequency analytical models. On the other hand, for lower J lf (or lower H lf ) again the simulation results deviate from analytical models. So this research work produces a relatively extensive set of simulation data that may be used to validate theories over a wide range of parameters. (paper)

  11. Value impact analysis of Generic Issue 143, Availability of Heating, Ventilation, Air Conditioning (HVAC) and Chilled Water Systems

    Energy Technology Data Exchange (ETDEWEB)

    Daling, P.M.; Marler, J.E.; Vo, T.V.; Phan, H.; Friley, J.R. [Pacific Northwest Lab., Richland, WA (United States)

    1993-11-01

    This study evaluates the values (benefits) and impacts (costs) associated with potential resolutions to Generic Issue 143, ``Availability of HVAC and Chilled Water Systems.`` The study identifies vulnerabilities related to failures of HVAC, chilled water, and room cooling systems; develops estimates of room heatup rates and safety-related equipment vulnerabilities following losses of HVAC/room cooler systems; develops estimates of the core damage frequencies and public risks associated with failures of these systems; develops three proposed resolution strategies to this generic issue; and performs a value/impact analysis of the proposed resolutions. Existing probabilistic risk assessments for four representative plants, including one plant from each vendor, form the basis for the core damage frequency and public risk calculations. Both internal and external events were considered. It was concluded that all three proposed resolution strategies exceed the $1,000/person-rem cost-effectiveness ratio. Additional evaluations were performed to develop ``generic`` insights on potential design-related and configuration-related vulnerabilities and potential high-frequency ({approximately}1E-04/RY) accident sequences that involve failures of HVAC/room cooling functions. It was concluded that, although high-frequency accident sequences may exist at some plants, these high-frequency sequences are plant-specific in nature or have been resolved through hardware and/or operational changes. The plant-specific Individual Plant Examinations are an effective vehicle for identification and resolution of these plant-specific anomalies and hardware configurations.

  12. Value impact analysis of Generic Issue 143, Availability of Heating, Ventilation, Air Conditioning (HVAC) and Chilled Water Systems

    International Nuclear Information System (INIS)

    Daling, P.M.; Marler, J.E.; Vo, T.V.; Phan, H.; Friley, J.R.

    1993-11-01

    This study evaluates the values (benefits) and impacts (costs) associated with potential resolutions to Generic Issue 143, ''Availability of HVAC and Chilled Water Systems.'' The study identifies vulnerabilities related to failures of HVAC, chilled water, and room cooling systems; develops estimates of room heatup rates and safety-related equipment vulnerabilities following losses of HVAC/room cooler systems; develops estimates of the core damage frequencies and public risks associated with failures of these systems; develops three proposed resolution strategies to this generic issue; and performs a value/impact analysis of the proposed resolutions. Existing probabilistic risk assessments for four representative plants, including one plant from each vendor, form the basis for the core damage frequency and public risk calculations. Both internal and external events were considered. It was concluded that all three proposed resolution strategies exceed the $1,000/person-rem cost-effectiveness ratio. Additional evaluations were performed to develop ''generic'' insights on potential design-related and configuration-related vulnerabilities and potential high-frequency (∼1E-04/RY) accident sequences that involve failures of HVAC/room cooling functions. It was concluded that, although high-frequency accident sequences may exist at some plants, these high-frequency sequences are plant-specific in nature or have been resolved through hardware and/or operational changes. The plant-specific Individual Plant Examinations are an effective vehicle for identification and resolution of these plant-specific anomalies and hardware configurations

  13. Impact-driven, frequency up-converting coupled vibration energy harvesting device for low frequency operation

    International Nuclear Information System (INIS)

    Gu, Lei; Livermore, Carol

    2011-01-01

    This paper presents experiments and models of an energy harvesting device in which a low frequency resonator impacts a high frequency energy harvesting resonator, resulting in energy harvesting predominantly at the system's coupled vibration frequency. Analysis shows that a reduced mechanical damping ratio during coupled vibration enables increased electrical power generation as compared with conventional technology. Experiments demonstrate that the efficiency of electrical power transfer is significantly improved with the coupled vibration approach. An average power output of 0.43 mW is achieved under 0.4g acceleration at 8.2 Hz, corresponding to a power density of 25.5 µW cm −3 . The measured power and power density at the resonant frequency are respectively 4.8 times and 13 times the measured peak values for a conventional harvester created from a low frequency beam alone

  14. Anhedonia reflects impairment in making relative value judgments between positive and neutral stimuli in schizophrenia.

    Science.gov (United States)

    Strauss, Gregory P; Visser, Katherine Frost; Keller, William R; Gold, James M; Buchanan, Robert W

    2018-02-27

    Anhedonia (i.e., diminished capacity to experience pleasure) has traditionally been viewed as a core symptom of schizophrenia (SZ). However, modern laboratory-based studies suggest that this definition may be incorrect, as hedonic capacity may be intact. Alternative conceptualizations have proposed that anhedonia may reflect an impairment in generating mental representations of affective value that are needed to guide decision-making and initiate motivated behavior. The current study evaluated this hypothesis in 42 outpatients with SZ and 19 healthy controls (CN) who completed two tasks: (a) an emotional experience task that required them to indicate how positive, negative, and calm/excited they felt in response to a single emotional or neutral photograph; (b) a relative value judgment task where they selected which of 2 photographs they preferred. Results indicated that SZ and CN reported similar levels of positive emotion and arousal in response to emotional and neutral stimuli; however, SZ reported higher negative affect for neutral and pleasant stimuli than CN. In the relative value judgment task, CN displayed clear preference for stimuli differing in valence; however, SZ showed less distinct preferences for positive over neutral stimuli. Findings suggest that although in-the-moment experiences of positive emotion to singular stimuli may be intact in SZ, the ability to make relative value judgments that are needed to guide decision-making is impaired. Original conceptualizations of anhedonia as a diminished capacity for pleasure in SZ may be inaccurate; anhedonia may more accurately reflect a deficit in relative value judgment that results from impaired value representation. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Transportation safety aspects of ore and related material - inconsistencies in current exemption values

    International Nuclear Information System (INIS)

    Rawl, R.R.; Leggett, R.W.; Eckerman, K.F.; Cook, J.R.

    2004-01-01

    The IAEA's system for exemption of material from the transport regulations is based on the fundamental principle that exemption values should be commensurate with the risk posed by the material, as represented by effective dose and skin dose. Important departures from that principle as well as inconsistencies between exemption values for different radionuclides have resulted from special provisions for natural materials that depend on their intended use, and from exposure scenarios and other assumptions and rules used in the derivation of exemption values. This paper examines the sources and extent of inconsistencies in exemption values for transport, particularly as they relate to naturally occurring radionuclides, and suggests ways to achieve greater internal consistency in exemption values as well as greater consistency with the fundamental principle underlying the current system

  16. Frequency of recommendations for additional imaging in diagnostic ultrasound examinations: Evaluation of radiologist, technologist, and other examination-related factors.

    Science.gov (United States)

    Margolis, Nathaniel E; Rosenkrantz, Andrew B; Babb, James S; Macari, Michael

    2015-10-01

    Our aim in this study was to evaluate the effect of the radiologist, technologist, and other examination-related factors on the frequency of recommendations for additional imaging (RAI) during sonographic (US) interpretation. We retrospectively reviewed 719 US reports from a single academic medical center for the presence of RAI. All studies had been interpreted by one of three abdominal radiologists. Examinations were performed at an outpatient radiology facility with no onsite radiologist (n = 299) or at an inpatient emergency department or hospital-based outpatient setting that had an onsite radiologist (n = 420). Possible associations between the frequency of RAI and the presence of an onsite radiologist, location of the examination, body part or region imaged, patient age, technologist performing the exam, and radiologist reading the exam were evaluated. There were significant differences between each pair of radiologists in terms of overall frequency of RAI (p technologists (13.6%-40.0%, p = 0.03). However, other factors such as patient age, patient sex, US unit, patient location, and radiologist location were not associated with the frequency of RAI (p = 0.15-0.93). The individual radiologist and technologist influenced the frequency of RAI for US examinations, whereas other examination-related factors did not. The observed substantial variability in RAI between radiologists and technologists warrants further study, with consideration of strategies to optimize RAI within US reports. © 2015 Wiley Periodicals, Inc.

  17. Molybdenum (6) determination by the method of high-frequency and pH titration

    International Nuclear Information System (INIS)

    Lukianets, I.G.; Kulish, N.G.

    1981-01-01

    A possibility to determine Mo(6) using the method of high frequency and pH-metric titration is investigated. By means of the high frequency contact R-cell Mo(6) titration is performed using different precipitators: 8-oxiquinoline, lead nitrate and acetate and silver nitrate. It is established that the best conditions are achieved during titration of 67.2-1343 mg/10 ml Mo(6) with lead acetate (pH 4.5-6.5). Relative standard deviation Ssub(r) constitutes 0.005 pH-metric titration of Mo(6) with complexone 3 is studied. The range of Mo(6) concentrations determined constitutes 13.43-134.3 mg at pH initial value of 3.5-5.5. Relative standard deviation Ssub(r) constitutes 0.003. Techniques of molybdenum determination in ferromolybdenum using the method of high frequency and pH-metric titration are developed [ru

  18. On the relation between ecosystem services, intrinsic value, existence value and economic valuation

    NARCIS (Netherlands)

    Davidson, M.D.

    2013-01-01

    Various attempts have been made to amalgamate the concepts of intrinsic value and ecosystem services, often with a stop-over at the economic concept of existence value. These attempts are based on a confusion of concepts, however. In this article, two types of non-use values are distinguished: warm

  19. Historical and future drought in Bangladesh using copula-based bivariate regional frequency analysis

    Science.gov (United States)

    Mortuza, Md Rubayet; Moges, Edom; Demissie, Yonas; Li, Hong-Yi

    2018-02-01

    The study aims at regional and probabilistic evaluation of bivariate drought characteristics to assess both the past and future drought duration and severity in Bangladesh. The procedures involve applying (1) standardized precipitation index to identify drought duration and severity, (2) regional frequency analysis to determine the appropriate marginal distributions for both duration and severity, (3) copula model to estimate the joint probability distribution of drought duration and severity, and (4) precipitation projections from multiple climate models to assess future drought trends. Since drought duration and severity in Bangladesh are often strongly correlated and do not follow same marginal distributions, the joint and conditional return periods of droughts are characterized using the copula-based joint distribution. The country is divided into three homogeneous regions using Fuzzy clustering and multivariate discordancy and homogeneity measures. For given severity and duration values, the joint return periods for a drought to exceed both values are on average 45% larger, while to exceed either value are 40% less than the return periods from the univariate frequency analysis, which treats drought duration and severity independently. These suggest that compared to the bivariate drought frequency analysis, the standard univariate frequency analysis under/overestimate the frequency and severity of droughts depending on how their duration and severity are related. Overall, more frequent and severe droughts are observed in the west side of the country. Future drought trend based on four climate models and two scenarios showed the possibility of less frequent drought in the future (2020-2100) than in the past (1961-2010).

  20. Relational Intimacy and Sexual Frequency: A Correlation or a Cause? A Clinical Study of Heterosexual Married Women.

    Science.gov (United States)

    Witherow, Marta Parkanyi; Chandraiah, Shambhavi; Seals, Samantha R; Bugan, Antal

    2016-01-01

    Researchers and practitioners have noted the importance of using clinical samples in sex therapy research. This study investigated the relationship between perceived levels of marital intimacy, sexual frequency, and sexual functioning among heterosexual married women. A clinical sample of 67 women completed the Couples Satisfaction Index (CSI), the Miller Social Intimacy Test (MSI), the Sexual Satisfaction Scale for Women (SSS-W), the Inclusion of the Other in the Self Scale (IOS), and the Female Sexual Functioning Index (FSFI-6). Data analyses revealed that marital intimacy acted as a predictor in univariate relationships on sexual frequency and sexual functioning but did not act as a mediator on sexual frequency and sexual functioning. Overall, these findings may further the discussion in the treatment of relational intimacy, sexual desire discrepancy, and female sexual dysfunction.

  1. Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations

    International Nuclear Information System (INIS)

    Philipp, M; Vergnat, C; Mueller, U; Sanctuary, R; Baller, J; Krueger, J K; Possart, W; Alnot, P

    2009-01-01

    The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

  2. Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, M; Vergnat, C; Mueller, U; Sanctuary, R; Baller, J; Krueger, J K [Laboratoire de Physique des Materiaux, Universite du Luxembourg, 162A, avenue de la Faiencerie, L-1511 Luxembourg (Luxembourg); Possart, W [Fachbereich Werkstoffwissenschaften, Universitaet des Saarlandes, D-66123 Saarbruecken (Germany); Alnot, P [LPMI, Universite Nancy (France)], E-mail: martine.philipp@uni.lu

    2009-01-21

    The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

  3. Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations.

    Science.gov (United States)

    Philipp, M; Vergnat, C; Müller, U; Sanctuary, R; Baller, J; Possart, W; Alnot, P; Krüger, J K

    2009-01-21

    The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

  4. Age-Related Frequency of Triple Negative Breast Cancer in Women

    International Nuclear Information System (INIS)

    Sajid, M. T.; Ahmad, M.; Mustafa, Q.; Shukr, I.; Azhar, M.

    2014-01-01

    Objective: To determine frequency of triple negative breast cancer (TNBC) in Pakistani women with respect to age. Study Design: Observational study. Place and Duration of Study: Armed Forces Institute of Pathology (AFIP), Rawalpindi, from July 2005 to July 2010. Methodology: Pathological records of all specimens of breast cancer were reviewed and data was obtained for estrogen receptor (ER), progesterone receptor (PR) and HER-2 neu receptor proteins. Specimens having complete record of all three proteins were included for analysis. TNBC was defined as those who were ER, PR and HER-2 neu negative. Overall frequency as well as frequency with respect to age was calculated. Descriptive and categorical variables were analyzed using SPSS version 17. Results: Eight hundred and fifteen patients out of 4715 (17.28%) were found to be TNBC. Mean age of diagnosis of TNBC was found to be 46.26 A +- 12.22 years of age while other breast cancers had a mean age 52.90 A +- 9.78 years (p 50 years while majority of patients with other breast cancers were elderly females (p < 0.001). Conclusion: TNBC comprised 17.28% of the breast cancers in Pakistani women diagnosed at the studied centre. A higher frequency of TNBC was noted in significantly younger patients. (author)

  5. Dietary restraint, anxiety, and the relative reinforcing value of snack food in non-obese women.

    Science.gov (United States)

    Goldfield, Gary S; Legg, Christine

    2006-11-01

    This study tested the independent and interactive effects of anxiety and dietary restraint on the relative reinforcing value of snack food. Thirty non-obese, female university students were assigned to one of four groups based on median split scores on measures of dietary restraint and state-anxiety: low-restraint/low-anxiety (n=7), low-restraint/high-anxiety (n=7), high-restraint/low-anxiety (n=9), and high-restraint/high-anxiety (n=7). Participants were provided the choice to earn points for palatable snack foods or fruits and vegetables using a computerized concurrent schedules choice task. The behavioural cost to gain access to snack foods increased across trials, whereas the cost to gain access to fruits and vegetables was held constant across trials. The relative reinforcing value of palatable snack food in relation to fruits and vegetables was defined as the total amount of points earned for snack food. Two-way analysis of covariance, with hunger and hedonic snack food ratings as covariates, showed that dietary restraint and anxiety had a significant interactive effect on the relative reinforcing value of snack food, indicating that the effect of anxiety on snack food reinforcement is moderated by dietary restraint. Specifically, the high-anxiety/low-restraint women found snack food significantly less reinforcing than low-anxiety/low-restraint women, but no differences emerged between high- and low-anxiety women with high-restraint. Neither restraint nor anxiety had an independent effect on the relative reinforcing value of snack food. These findings indicate that anxiety may have a suppressive effect on the relative reinforcing value of snack food in low-restrained eaters, but not an enhancing effect on snack food reinforcement in high-restrained eaters. Clinical implications of these findings are discussed.

  6. Committee Representation and Medicare Reimbursements-An Examination of the Resource-Based Relative Value Scale.

    Science.gov (United States)

    Gao, Y Nina

    2018-04-06

    The Resource-Based Relative Value Scale Update Committee (RUC) submits recommended reimbursement values for physician work (wRVUs) under Medicare Part B. The RUC includes rotating representatives from medical specialties. To identify changes in physician reimbursements associated with RUC rotating seat representation. Relative Value Scale Update Committee members 1994-2013; Medicare Part B Relative Value Scale 1994-2013; Physician/Supplier Procedure Summary Master File 2007; Part B National Summary Data File 2000-2011. I match service and procedure codes to specialties using 2007 Medicare billing data. Subsequently, I model wRVUs as a function of RUC rotating committee representation and level of code specialization. An annual RUC rotating seat membership is associated with a statistically significant 3-5 percent increase in Medicare expenditures for codes billed to that specialty. For codes that are performed by a small number of physicians, the association between reimbursement and rotating subspecialty representation is positive, 0.177 (SE = 0.024). For codes that are performed by a large number of physicians, the association is negative, -0.183 (SE = 0.026). Rotating representation on the RUC is correlated with overall reimbursement rates. The resulting differential changes may exacerbate existing reimbursement discrepancies between generalist and specialist practitioners. © Health Research and Educational Trust.

  7. Frequency-dependent complex modulus of the uterus: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Kiss, Miklos Z [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States); Hobson, Maritza A [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States); Varghese, Tomy [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States); Harter, Josephine [Department of Surgical Pathology, University of Wisconsin, Madison, WI 53706 (United States); Kliewer, Mark A [Department of Radiology, University of Wisconsin, Madison, WI 53706 (United States); Hartenbach, Ellen M [Department of Obstetrics and Gynecology, University of Wisconsin, Madison, WI 53706 (United States); Zagzebski, James A [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2006-08-07

    The frequency-dependent complex moduli of human uterine tissue have been characterized. Quantification of the modulus is required for developing uterine ultrasound elastography as a viable imaging modality for diagnosing and monitoring causes for abnormal uterine bleeding and enlargement, as well assessing the integrity of uterine and cervical tissue. The complex modulus was measured in samples from hysterectomies of 24 patients ranging in age from 31 to 79 years. Measurements were done under small compressions of either 1 or 2%, at low pre-compression values (either 1 or 2%), and over a frequency range of 0.1-100 Hz. Modulus values of cervical tissue monotonically increased from approximately 30-90 kPa over the frequency range. Normal uterine tissue possessed modulus values over the same range, while leiomyomas, or uterine fibroids, exhibited values ranging from approximately 60-220 kPa.

  8. Frequency-dependent complex modulus of the uterus: preliminary results

    International Nuclear Information System (INIS)

    Kiss, Miklos Z; Hobson, Maritza A; Varghese, Tomy; Harter, Josephine; Kliewer, Mark A; Hartenbach, Ellen M; Zagzebski, James A

    2006-01-01

    The frequency-dependent complex moduli of human uterine tissue have been characterized. Quantification of the modulus is required for developing uterine ultrasound elastography as a viable imaging modality for diagnosing and monitoring causes for abnormal uterine bleeding and enlargement, as well assessing the integrity of uterine and cervical tissue. The complex modulus was measured in samples from hysterectomies of 24 patients ranging in age from 31 to 79 years. Measurements were done under small compressions of either 1 or 2%, at low pre-compression values (either 1 or 2%), and over a frequency range of 0.1-100 Hz. Modulus values of cervical tissue monotonically increased from approximately 30-90 kPa over the frequency range. Normal uterine tissue possessed modulus values over the same range, while leiomyomas, or uterine fibroids, exhibited values ranging from approximately 60-220 kPa

  9. An assessment of threshold shifts in nonprofessional pop/rock musicians using conventional and extended high-frequency audiometry.

    Science.gov (United States)

    Schmuziger, Nicolas; Patscheke, Jochen; Probst, Rudolf

    2007-09-01

    The clinical value of extended high-frequency audiometry for the detection of noise-induced hearing loss has not been established conclusively. The purpose of this study was to assess the relative temporary threshold shift (TTS) in two frequency regions (conventional versus extended high frequency). In this exploratory study, pure-tone thresholds from 0.5 to 14 kHz were measured in both ears of 16 nonprofessional pop/rock musicians (mean age, 35 yr; range, 27 to 49 yr), before and after a 90-minute rehearsal session. All had experienced repeated exposures to intense sound levels during at least 5 yr of their musical careers. After the rehearsal, median threshold levels were found to be significantly poorer for frequencies from 0.5 to 8 kHz (Wilcoxon signed rank test, p frequency range from 9 to 14 kHz. Decreases in the median threshold values measured before the rehearsal were present across the conventional frequency range, most notably at 6 kHz, but were not observed in the extended high-frequency range. On the basis of these results, extended high-frequency audiometry does not seem advantageous as a means of the early detection of noise-induced hearing loss.

  10. Joint spatiotemporal variability of global sea surface temperatures and global Palmer drought severity index values

    Science.gov (United States)

    Apipattanavis, S.; McCabe, G.J.; Rajagopalan, B.; Gangopadhyay, S.

    2009-01-01

    Dominant modes of individual and joint variability in global sea surface temperatures (SST) and global Palmer drought severity index (PDSI) values for the twentieth century are identified through a multivariate frequency domain singular value decomposition. This analysis indicates that a secular trend and variability related to the El Niño–Southern Oscillation (ENSO) are the dominant modes of variance shared among the global datasets. For the SST data the secular trend corresponds to a positive trend in Indian Ocean and South Atlantic SSTs, and a negative trend in North Pacific and North Atlantic SSTs. The ENSO reconstruction shows a strong signal in the tropical Pacific, North Pacific, and Indian Ocean regions. For the PDSI data, the secular trend reconstruction shows high amplitudes over central Africa including the Sahel, whereas the regions with strong ENSO amplitudes in PDSI are the southwestern and northwestern United States, South Africa, northeastern Brazil, central Africa, the Indian subcontinent, and Australia. An additional significant frequency, multidecadal variability, is identified for the Northern Hemisphere. This multidecadal frequency appears to be related to the Atlantic multidecadal oscillation (AMO). The multidecadal frequency is statistically significant in the Northern Hemisphere SST data, but is statistically nonsignificant in the PDSI data.

  11. Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals.

    Science.gov (United States)

    Zhang, Y; Huang, S L; Wang, S; Zhao, W

    2016-05-01

    The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert-Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of wave detection signals.

  12. Building Evidence of Validity: The Relation between Work Values, Interests, Personality, and Personal Values

    Science.gov (United States)

    Leuty, Melanie E.; Hansen, Jo-Ida C.

    2013-01-01

    The current study used work values components (WVC) to examine the relationship between work values, vocational interests, personality, and personal values. Most intercorrelations between work values and other constructs were in the small effect range. Overall correlations between scale scores provided evidence of convergent and discriminant…

  13. Reproducibility and relative validity of a food frequency questionnaire to estimate intake of dietary phylloquinone and menaquinones

    Science.gov (United States)

    Background: Several observational studies have investigated the relation of dietary phylloquinone and menaquinone intake with occurrence of chronic diseases. Most of these studies relied on food frequency questionnaires (FFQ) to estimate the intake of phylloquinone and menaquinones. However, none of...

  14. Reproducibility and relative validity of a food frequency questionnaire to estimate intake of dietary phylloquinone and menaquinones.

    NARCIS (Netherlands)

    Zwakenberg, S R; Engelen, A I P; Dalmeijer, G W; Booth, S L; Vermeer, C; Drijvers, J J M M; Ocke, M C; Feskens, E J M; van der Schouw, Y T; Beulens, J W J

    2017-01-01

    This study aims to investigate the reproducibility and relative validity of the Dutch food frequency questionnaire (FFQ), to estimate intake of dietary phylloquinone and menaquinones compared with 24-h dietary recalls (24HDRs) and plasma markers of vitamin K status.

  15. A 'new' Cromer-related high frequency antigen probably antithetical to WES.

    Science.gov (United States)

    Daniels, G L; Green, C A; Darr, F W; Anderson, H; Sistonen, P

    1987-01-01

    An antibody to a high frequency antigen, made in a WES+ Black antenatal patient (Wash.), failed to react with the red cells of a presumed WES+ homozygote and is, therefore, probably antithetical to anti-WES. Like anti-WES, it reacted with papain, ficin, trypsin or neuraminidase treated cells but not with alpha-chymotrypsin or pronase treated cells and was specifically inhibited by concentrated serum. It also reacted more strongly in titration with WES- cells than with WES+ cells. The antibody is Cromer-related as it failed to react with Inab phenotype (IFC-) cells and reacted only weakly with Dr(a-) cells. Wash. cells and those of the other possible WES+ homozygote are Cr(a+) Tc(a+b-c-) Dr(a+) IFC+ but reacted only very weakly with anti-Esa.

  16. Single frequency semiconductor lasers

    CERN Document Server

    Fang, Zujie; Chen, Gaoting; Qu, Ronghui

    2017-01-01

    This book systematically introduces the single frequency semiconductor laser, which is widely used in many vital advanced technologies, such as the laser cooling of atoms and atomic clock, high-precision measurements and spectroscopy, coherent optical communications, and advanced optical sensors. It presents both the fundamentals and characteristics of semiconductor lasers, including basic F-P structure and monolithic integrated structures; interprets laser noises and their measurements; and explains mechanisms and technologies relating to the main aspects of single frequency lasers, including external cavity lasers, frequency stabilization technologies, frequency sweeping, optical phase locked loops, and so on. It paints a clear, physical picture of related technologies and reviews new developments in the field as well. It will be a useful reference to graduate students, researchers, and engineers in the field.

  17. Chromosomal aberrations and micronuclei frequencies in Bulgarian control population

    International Nuclear Information System (INIS)

    Popova, I.; Hadjidekova, V.; Hristova, R.; Atanasova, P.

    2004-01-01

    The aim of this investigation is to represent the frequency of spontaneous chromosomal damages in peripheral blood lymphocytes of Bulgarian control population. Material and methods: The investigated group includes persons belonging to both sexes and different ages. Each of them is interviewed of their social and health status. Sixteen persons are examined using the chromosomal aberrations analysis and forty-five with micronucleus test. The frequency of chromosomal aberrations varied between 0 - 2.4 % and the mean value is 1.00 %. The frequency of cells with micronuclei varied between 4.5 - 24.5 % and the mean value 12,9 %. Further work on the investigation of spontaneous frequency of chromosomal damages is in progress. (authors)

  18. Patients' Values Related to Treatment Options for Teeth with Apical Periodontitis.

    Science.gov (United States)

    Azarpazhooh, Amir; Dao, Thuan; Ungar, Wendy J; Da Costa, Jose; Figueiredo, Rafael; Krahn, Murray; Friedman, Shimon

    2016-03-01

    This study aimed to explore patients' values when selecting treatment for a tooth with apical periodontitis (AP), namely retention via root canal treatment (RCT) and extraction without replacement or replacement with implant-supported crowns or fixed or removable partial prostheses. Through 2 surveys of patients (800 university patients and 200 community patients, response rate = 43%) and dentists (498 Ontario endodontists, periodontists, prosthodontists, oral and maxillofacial surgeons, response rate = 40% and 1983 Ontario general dentists, response rate = 15%), the importance of values that might be considered important to patients when selecting treatment options for a tooth with AP were recorded. Chi-square and Kendall's tau tests were used to respectively compare the importance rating frequency by each surveyed group and its correlation to their demographic variables (P ≤ .05). Patients considered communication and trust (94%), tooth retention (90%), esthetic outcome (84% regardless of location), cost (83%), longevity (83%), and preoperative pain (81%) as the most important decision values. Dentists overrated the importance of patients' previous experience with the treatment options (94% vs. 72%), dental insurance (90% vs. 70%), and intraoperative pain (79% vs. 60%) while underestimating the importance of maintenance cost (60% vs. 79%). Dentists should respect patients' views about esthetic outcome, longevity, and cost associated with treatment options for a tooth with AP. In particular, this survey highlights the value of communication and trust between patient and dentist and preservation of the natural tooth through RCT over implant-supported crown replacement when planning treatment for a tooth with AP. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. The Cut-off Value of Blood Mercury Concentration in Relation to Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Seok-Hoon Lee

    2017-09-01

    Full Text Available Background : Increased blood mercury concentration is associated with inflammation, and chronic inflammation can cause insulin resistance. We examined the cut-off value of blood mercury in relation to an increased score on the homeostasis model assessment for insulin resistance (HOMA-IR. Methods : We used data from the Korean National Health and Nutrition Examination Survey (2008–2010. Relevant data from 5,184 subjects (2,523 men and 2,661 women were analyzed cross-sectionally. General linear analysis was performed to evaluate the relationship between HOMA-IR score and blood mercury concentration. In addition, we determined the cut-off value of blood mercury concentration in relation to increased HOMA-IR score (> 2.34 using an ROC curve. Results : The mean value of blood mercury concentration in men and women was 5.88 μg/L and 4.11 μg/L, respectively. In men, comparing to the first quartile, HOMA-IR score increased significantly in the third and fourth blood mercury quartiles. In women, however, the increase in HOMA-IR score was not significant. The cut-off value that best represented the association between increased HOMA-IR score and blood mercury concentration in men was found to be 4.71 μg/L. Conclusion : Blood mercury concentration was associated with increased HOMA-IR score in men, and the cut-off value of blood mercury concentration that was correlated with increased HOMA-IR score was around 4.71 μg/L.

  20. Overestimating resource value and its effects on fighting decisions.

    Directory of Open Access Journals (Sweden)

    Lee Alan Dugatkin

    Full Text Available Much work in behavioral ecology has shown that animals fight over resources such as food, and that they make strategic decisions about when to engage in such fights. Here, we examine the evolution of one, heretofore unexamined, component of that strategic decision about whether to fight for a resource. We present the results of a computer simulation that examined the evolution of over- or underestimating the value of a resource (food as a function of an individual's current hunger level. In our model, animals fought for food when they perceived their current food level to be below the mean for the environment. We considered seven strategies for estimating food value: 1 always underestimate food value, 2 always overestimate food value, 3 never over- or underestimate food value, 4 overestimate food value when hungry, 5 underestimate food value when hungry, 6 overestimate food value when relatively satiated, and 7 underestimate food value when relatively satiated. We first competed all seven strategies against each other when they began at approximately equal frequencies. In such a competition, two strategies--"always overestimate food value," and "overestimate food value when hungry"--were very successful. We next competed each of these strategies against the default strategy of "never over- or underestimate," when the default strategy was set at 99% of the population. Again, the strategies of "always overestimate food value" and "overestimate food value when hungry" fared well. Our results suggest that overestimating food value when deciding whether to fight should be favored by natural selection.

  1. Impact of physiological variables and genetic background on myocardial frequency-resistivity relations in the intact beating murine heart.

    Science.gov (United States)

    Reyes, Maricela; Steinhelper, Mark E; Alvarez, Jorge A; Escobedo, Daniel; Pearce, John; Valvano, Jonathan W; Pollock, Brad H; Wei, Chia-Ling; Kottam, Anil; Altman, David; Bailey, Steven; Thomsen, Sharon; Lee, Shuko; Colston, James T; Oh, Jung Hwan; Freeman, Gregory L; Feldman, Marc D

    2006-10-01

    Conductance measurements for generation of an instantaneous left ventricular (LV) volume signal in the mouse are limited, because the volume signal is a combination of blood and LV muscle, and only the blood signal is desired. We have developed a conductance system that operates at two simultaneous frequencies to identify and remove the myocardial contribution to the instantaneous volume signal. This system is based on the observation that myocardial resistivity varies with frequency, whereas blood resistivity does not. For calculation of LV blood volume with the dual-frequency conductance system in mice, in vivo murine myocardial resistivity was measured and combined with an analytic approach. The goals of the present study were to identify and minimize the sources of error in the measurement of myocardial resistivity to enhance the accuracy of the dual-frequency conductance system. We extended these findings to a gene-altered mouse model to determine the impact of measured myocardial resistivity on the calculation of LV pressure-volume relations. We examined the impact of temperature, timing of the measurement during the cardiac cycle, breeding strain, anisotropy, and intrameasurement and interanimal variability on the measurement of intact murine myocardial resistivity. Applying this knowledge to diabetic and nondiabetic 11- and 20- to 24-wk-old mice, we demonstrated differences in myocardial resistivity at low frequencies, enhancement of LV systolic function at 11 wk and LV dilation at 20-24 wk, and histological and electron-microscopic studies demonstrating greater glycogen deposition in the diabetic mice. This study demonstrated the accurate technique of measuring myocardial resistivity and its impact on the determination of LV pressure-volume relations in gene-altered mice.

  2. The Value of Value

    DEFF Research Database (Denmark)

    Sørensen, Asger

    parts of business ethics given prominence to especially one term, namely `value'. The question that interests me is the following: What does the articulation of ethics and morality in terms of values mean for ethics and morality as such. Or, to put the question in a more fashionably way: What......As a social scientist of ethics and morality, Luhmann has noticed the ethical wave that has recently swept across the western world, and states that this particular kind of wave seems to have a wavelength of about one hundred years (cf. Luhmann 1989: 9 ff.). Even though the frequency...... and the regularity of such a phenomenon is both hard to verify and, if true, difficult to explain, it seems fair to say that since the Enlightenment, an approaching fin-de-siecle has brought an increased interest in matters concerning morality and ethics.1 The present peak has in public-political discourse and some...

  3. A Generalized Analytic Operator-Valued Function Space Integral and a Related Integral Equation

    International Nuclear Information System (INIS)

    Chang, K.S.; Kim, B.S.; Park, C.H.; Ryu, K.S.

    2003-01-01

    We introduce a generalized Wiener measure associated with a Gaussian Markov process and define a generalized analytic operator-valued function space integral as a bounded linear operator from L p into L p-ci r cumflexprime (1< p ≤ 2) by the analytic continuation of the generalized Wiener integral. We prove the existence of the integral for certain functionals which involve some Borel measures. Also we show that the generalized analytic operator-valued function space integral satisfies an integral equation related to the generalized Schroedinger equation. The resulting theorems extend the theory of operator-valued function space integrals substantially and previous theorems about these integrals are generalized by our results

  4. Dose-response curve for translocation frequency with single pair of painted chromosome. A comparison with dicentric and micronuclei frequency

    Energy Technology Data Exchange (ETDEWEB)

    Venkatachalam, P.; Paul, S.F.D.; Mohankumar, M.N.; Prabhu, B.K.; Gajendiran, N.; Jeevanram, R.K

    2000-07-01

    A translocation dose-response curve using a single pair of painted chromosomes was constructed. The translocation frequencies observed at different doses were compared to those obtained for dicentrics (DC) and micronuclei (MN). The translocation and DC frequency followed the Poisson distribution and MN showed over-dispersion. The translocation and DC frequencies were nearly the same for each dose point. Micronuclei showed a comparatively lower frequency. The alpha/beta ratio for translocations (0.916) and DC (0.974) were comparable, whereas the value for MN (1.526) was much higher. The equal frequencies of translocations and DC observed for a given dose indicated that genomic translocation frequency estimated using a single pair of painted chromosomes provides a reliable and easy method to measure translocation frequency. (autho000.

  5. Dose-response curve for translocation frequency with single pair of painted chromosome. A comparison with dicentric and micronuclei frequency

    International Nuclear Information System (INIS)

    Venkatachalam, P.; Paul, S.F.D.; Mohankumar, M.N.; Prabhu, B.K.; Gajendiran, N.; Jeevanram, R.K.

    2000-01-01

    A translocation dose-response curve using a single pair of painted chromosomes was constructed. The translocation frequencies observed at different doses were compared to those obtained for dicentrics (DC) and micronuclei (MN). The translocation and DC frequency followed the Poisson distribution and MN showed over-dispersion. The translocation and DC frequencies were nearly the same for each dose point. Micronuclei showed a comparatively lower frequency. The alpha/beta ratio for translocations (0.916) and DC (0.974) were comparable, whereas the value for MN (1.526) was much higher. The equal frequencies of translocations and DC observed for a given dose indicated that genomic translocation frequency estimated using a single pair of painted chromosomes provides a reliable and easy method to measure translocation frequency. (author)

  6. Relative validity and reproducibility of a food frequency questionnaire used in pregnant women from a rural area of China.

    Science.gov (United States)

    Li, Min; Halldorsson, Thorhallur I; Bjerregaard, Anne A; Che, Yan; Mao, Yanyan; Hu, Wenfu; Wang, Yu; Zhou, Weijin; Olsen, Sjúrdur F; Strøm, Marin

    2014-11-01

    Food frequency questionnaires are relatively inexpensive, easy and quick to administer, but the construction of a food frequency questionnaire that can capture Chinese food habits is challenging given the diverse lifestyle and eating habits in different parts of the country. The aim of this study was to assess the validity and reproducibility of a self-administered food frequency questionnaire against a 3-day dietary recall in a rural region of western China. Prospective cohort study. Chinese maternal and child healthcare hospital. A total of 168 healthy pregnant women. Pregnant women completed a food frequency questionnaire at 16-24 weeks gestation, and again at 29-31 weeks; during weeks 26-27 they completed a 3-day dietary recall. In general, mean intake was higher when assessed with food frequency questionnaires compared with dietary recall. Spearman and intra-class correlation coefficients between the two food frequency questionnaires ranged from 0.31 to 0.69 and from 0.27 to 0.79, respectively. For the second food frequency questionnaire and the dietary recall, the crude and de-attenuated Spearman correlations ranged from 0.12 to 0.55 and 0.14 to 0.58, respectively. The correlation both between the two food frequency questionnaires and between the second food frequency questionnaire and the dietary recall decreased after adjustment for energy. Ranking women, 31-57% and 1-8% were classified into the same and the opposite quartile, respectively, by both food frequency questionnaires; 30-45% and 1-11% were classified into the same and the opposite quartile respectively for the second food frequency questionnaire and dietary recall. The food frequency questionnaire showed good reproducibility and correlations with dietary recall; it is useful for ranking study participants according to dietary intake, which is of great importance to future etiological studies in this cohort. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

  7. Hematological parameters in relation to age, sex and biochemical values for mute swans (Cygnus olor).

    Science.gov (United States)

    Dolka, B; Włodarczyk, R; Zbikowski, A; Dolka, I; Szeleszczuk, P; Kluciński, W

    2014-06-01

    The knowledge of the correct morphological and biochemical parameters in mute swans is an important indicator of their health status, body condition, adaptation to habitat and useful diagnostic tools in veterinary practice and ecological research. The aim of the study was to obtain hematological parameters in relation to age, sex and serum biochemistry values in wild-living mute swans. We found the significant differences in the erythrocyte count, hematocrit, hemoglobin concentration and erythrocyte sedimentation rate in relation to age of mute swans. There were no differences in hematological values between males and females. The leukogram and H/L ratio did not vary by age and sex in swans. Among of biochemical parameters the slightly increased AST, ALP, CK, K, urea, decreased CHOL and TG values were recorded. As far as we know, this is the first study in which the morphometric parameters of blood cells in mute swans were presented. We found extremely low concentration of lead in blood (at subthreshold level). No blood parasites were found in blood smears. The analysis of body mass and biometric parameters revealed a significant differences dependent on age and sex. No differences in the scaled mass index were found. Our results represent a normal hematologic and blood chemistry values and age-sex related changes, as reference values for the mute swan.

  8. Effect of feed-related farm characteristics on relative values of genetic traits in dairy cows to reduce greenhouse gas emissions along the chain.

    Science.gov (United States)

    Van Middelaar, C E; Berentsen, P B M; Dijkstra, J; Van Arendonk, J A M; De Boer, I J M

    2015-07-01

    Breeding has the potential to reduce greenhouse gas (GHG) emissions from dairy farming. Evaluating the effect of a 1-unit change (i.e., 1 genetic standard deviation improvement) in genetic traits on GHG emissions along the chain provides insight into the relative importance of genetic traits to reduce GHG emissions. Relative GHG values of genetic traits, however, might depend on feed-related farm characteristics. The objective of this study was to evaluate the effect of feed-related farm characteristics on GHG values by comparing the values of milk yield and longevity for an efficient farm and a less efficient farm. The less efficient farm did not apply precision feeding and had lower feed production per hectare than the efficient farm. Greenhouse gas values of milk yield and longevity were calculated by using a whole-farm model and 2 different optimization methods. Method 1 optimized farm management before and after a change in genetic trait by maximizing labor income; the effect on GHG emissions (i.e., from production of farm inputs up to the farm gate) was considered a side effect. Method 2 optimized farm management after a change in genetic trait by minimizing GHG emissions per kilogram of milk while maintaining labor income and milk production at least at the level before the change in trait; the effect on labor income was considered a side effect. Based on maximizing labor income (method 1), GHG values of milk yield and longevity were, respectively, 279 and 143kg of CO2 equivalents (CO2e)/unit change per cow per year on the less efficient farm, and 247 and 210kg of CO2e/unit change per cow per year on the efficient farm. Based on minimizing GHG emissions (method 2), GHG values of milk yield and longevity were, respectively, 538 and 563kg of CO2e/unit change per cow per year on the less efficient farm, and 453 and 441kg of CO2e/unit change per cow per year on the efficient farm. Sensitivity analysis showed that, for both methods, the absolute effect of a

  9. Normal cranial bone marrow MR imaging pattern with age-related ADC value distribution

    International Nuclear Information System (INIS)

    Li Qi; Pan Shinong; Yin Yuming; Li Wei; Chen Zhian; Liu Yunhui; Wu Zhenhua; Guo Qiyong

    2011-01-01

    Objective: To determine MRI appearances of normal age-related cranial bone marrow and the relationship between MRI patterns and apparent diffusion coefficient (ADC) values. Methods: Five hundred subjects were divided into seven groups based on ages. Cranial bone marrow MRI patterns were performed based on different thickness of the diploe and signal intensity distribution characteristics. ADC values of the frontal, parietal, occipital and temporal bones on DWI were measured and calculated. Correlations between ages and ADC values, between patterns and ADC values, as well as the distribution of ADC values were analyzed. Results: Normal cranial bone marrow was divided into four types and six subtypes, Type I, II, III and IV, which had positive correlation with age increasing (χ 2 = 266.36, P 0.05). In addition, there was significant negative correlation between the ADC values and MRI patterns in the normal parietal and occipital bones (r = -0.691 and -0.750, P < 0.01). Conclusion: The combination of MRI features and ADC values changes in different cranial bones showed significant correlation with age increasing. Familiar with the MRI appearance of the normal bone marrow conversion pattern in different age group and their ADC value will aid the diagnosis and differential of the cranial bone pathology.

  10. A model for the relation between stimulus frequency and spontaneous otoacoustic emissions in lizard papillae.

    Science.gov (United States)

    Wit, Hero P; van Dijk, Pim; Manley, Geoffrey A

    2012-11-01

    Spontaneous otoacoustic emissions (SOAEs) and stimulus frequency otoacoustic emissions (SFOAEs) have been described from lizard ears. Although there are several models for these systems, none has modeled the characteristics of both of these types of otoacoustic emissions based upon their being derived from hair cells as active oscillators. Data from the ears of two lizard species, one lacking a tectorial membrane and one with a chain of tectorial sallets, as described by Bergevin et al. ["Coupled, active oscillators and lizard otoacoustic emissions," AIP Conf. Proc. 1403, 453 (2008)], are modeled as an array of coupled self-sustained oscillators. The model, originally developed by Vilfan and Duke ["Frequency clustering in spontaneous otoacoustic emissions from a lizard's ear," Biophys. J. 95, 4622-4630 (2008)], well describes both the amplitude and phase characteristics of SFOAEs and the relation between SFOAEs and SOAEs.

  11. Interpretations of Frequency Domain Analyses of Neural Entrainment: Periodicity, Fundamental Frequency, and Harmonics.

    Science.gov (United States)

    Zhou, Hong; Melloni, Lucia; Poeppel, David; Ding, Nai

    2016-01-01

    Brain activity can follow the rhythms of dynamic sensory stimuli, such as speech and music, a phenomenon called neural entrainment. It has been hypothesized that low-frequency neural entrainment in the neural delta and theta bands provides a potential mechanism to represent and integrate temporal information. Low-frequency neural entrainment is often studied using periodically changing stimuli and is analyzed in the frequency domain using the Fourier analysis. The Fourier analysis decomposes a periodic signal into harmonically related sinusoids. However, it is not intuitive how these harmonically related components are related to the response waveform. Here, we explain the interpretation of response harmonics, with a special focus on very low-frequency neural entrainment near 1 Hz. It is illustrated why neural responses repeating at f Hz do not necessarily generate any neural response at f Hz in the Fourier spectrum. A strong neural response at f Hz indicates that the time scales of the neural response waveform within each cycle match the time scales of the stimulus rhythm. Therefore, neural entrainment at very low frequency implies not only that the neural response repeats at f Hz but also that each period of the neural response is a slow wave matching the time scale of a f Hz sinusoid.

  12. Phonons in models for icosahedral quasicrystals: low frequency behaviour an inelastic scattering properties

    International Nuclear Information System (INIS)

    Los, J.; Janssen, T.; Gaehler, F.

    1993-01-01

    A detailed study of the low frequency behaviour of the phonon spectrum for 3-dimensional tiling models of icosahedral quasicrystals is presented, in commensurate approximations with up to 10336 atoms per unit cell. The scaling behaviour of the lowest phonon branches shows that the widths of the gaps relative to the bandwidths vanish in the low frequency limit. The density of states at low frequencies is calculated by Brillouin zone integration, using either local linear or local quadratic interpolation of the branch surface. For perfect approximants it appears that there is a deviation from the normal ω 2 -behaviour already at relatively low frequencies, in the form of pseudogaps. Also randomized approximants are considered, and it turns out that the pseudogaps in the density of states are flattened by randomization. When approaching the quasiperiodic limit, the dispersion of the acoustic branches becomes more and more isotropic, and the two transversal sound velocities tend to the same value. The dynamical structure factor is determined for several approximants, and it is shown that the linearity and the isotropy of the dispersion are extended far beyond the range of the acoustic branches inside the Brillouin zone. A sharply peaked response is observed at low frequencies, and broadening at higher frequencies. To obtain these results, an efficient algorithm based on Lanczos tridiagonalisation is used. (orig.)

  13. Combining agreement and frequency rating scales to optimize psychometrics in measuring behavioral health functioning.

    Science.gov (United States)

    Marfeo, Elizabeth E; Ni, Pengsheng; Chan, Leighton; Rasch, Elizabeth K; Jette, Alan M

    2014-07-01

    The goal of this article was to investigate optimal functioning of using frequency vs. agreement rating scales in two subdomains of the newly developed Work Disability Functional Assessment Battery: the Mood & Emotions and Behavioral Control scales. A psychometric study comparing rating scale performance embedded in a cross-sectional survey used for developing a new instrument to measure behavioral health functioning among adults applying for disability benefits in the United States was performed. Within the sample of 1,017 respondents, the range of response category endorsement was similar for both frequency and agreement item types for both scales. There were fewer missing values in the frequency items than the agreement items. Both frequency and agreement items showed acceptable reliability. The frequency items demonstrated optimal effectiveness around the mean ± 1-2 standard deviation score range; the agreement items performed better at the extreme score ranges. Findings suggest an optimal response format requires a mix of both agreement-based and frequency-based items. Frequency items perform better in the normal range of responses, capturing specific behaviors, reactions, or situations that may elicit a specific response. Agreement items do better for those whose scores are more extreme and capture subjective content related to general attitudes, behaviors, or feelings of work-related behavioral health functioning. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Size, Book-to-Market Ratio and Relativity of Accounting Information Value: Empirical Research on the Chinese Listed Company

    Science.gov (United States)

    Yu, Jing; Cheng, Siwei; Xu, Bin

    Recently there are many literatures studying the effect of factors such as size or book-market ratio on fluctuation of accounting earnings, stock price or earnings respectively, but so far their affection on accounting information value relativity has been scarcely addressed. This paper presents the detail analyses of their effect of the two factors to the relativity of accounting information value respectively by taking Shanghai and Shenzhen stock markets as sample. And the analyses supports the following two hypotheses, (1) The relativity of accounting information value of big size corporation is more than that of small size corporation. (2) The relativity of accounting information value of low B/M ratio corporation is more than that of low B/M ratio corporation.

  15. Automatic oscillator frequency control system

    Science.gov (United States)

    Smith, S. F. (Inventor)

    1985-01-01

    A frequency control system makes an initial correction of the frequency of its own timing circuit after comparison against a frequency of known accuracy and then sequentially checks and corrects the frequencies of several voltage controlled local oscillator circuits. The timing circuit initiates the machine cycles of a central processing unit which applies a frequency index to an input register in a modulo-sum frequency divider stage and enables a multiplexer to clock an accumulator register in the divider stage with a cyclical signal derived from the oscillator circuit being checked. Upon expiration of the interval, the processing unit compares the remainder held as the contents of the accumulator against a stored zero error constant and applies an appropriate correction word to a correction stage to shift the frequency of the oscillator being checked. A signal from the accumulator register may be used to drive a phase plane ROM and, with periodic shifts in the applied frequency index, to provide frequency shift keying of the resultant output signal. Interposition of a phase adder between the accumulator register and phase plane ROM permits phase shift keying of the output signal by periodic variation in the value of a phase index applied to one input of the phase adder.

  16. Daily meal frequency and associated variables in children and adolescents.

    Science.gov (United States)

    Silva, Fabiana A; Candiá, Samara M; Pequeno, Marina S; Sartorelli, Daniela S; Mendes, Larissa L; Oliveira, Renata M S; Netto, Michele P; Cândido, Ana Paula C

    To investigate the frequency distribution of daily meals and its relation to demographic, socioeconomic, behavioral, anthropometric and biochemical factors in children and adolescents. This was a cross-sectional study with a representative sample of 708 schoolchildren aged 7-14 years. Data on personal information, socioeconomic status, physical activity and number of meals were obtained through semi-structured questionnaire and consumption by 24-h recall and food record. Weight and height measurements were also performed to calculate the body mass index. Finally, blood samples were collected for analysis of total cholesterol, high- and low density lipoprotein, triglyceride, and glucose levels. Descriptive statistics, the Mann-Whitney test, and Poisson regression were used in statistical analysis. Meal frequency 2 (PR=1.53; 95% CI: 1.11-2.11; p=0.010). Even in the age group of 10-14 years, <4 meals was related to higher prevalence of body mass index (PR=1.33; 95% CI: 1.02-1.74; p=0.032) and low-density lipoprotein (PR=1.39; 95% CI: 1.03-1.87; p=0.030) higher after adjustments. Lower frequency of meals was related to lower income in children and adolescents, larger number of sons in the family, and increased values of body mass index and low-density lipoprotein. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  17. Daily meal frequency and associated variables in children and adolescents,

    Directory of Open Access Journals (Sweden)

    Fabiana A. Silva

    Full Text Available Abstract: Objective: To investigate the frequency distribution of daily meals and its relation to demographic, socioeconomic, behavioral, anthropometric and biochemical factors in children and adolescents. Methods: This was a cross-sectional study with a representative sample of 708 schoolchildren aged 7-14 years. Data on personal information, socioeconomic status, physical activity and number of meals were obtained through semi-structured questionnaire and consumption by 24-h recall and food record. Weight and height measurements were also performed to calculate the body mass index. Finally, blood samples were collected for analysis of total cholesterol, high- and low density lipoprotein, triglyceride, and glucose levels. Descriptive statistics, the Mann-Whitney test, and Poisson regression were used in statistical analysis. Results: Meal frequency 2 (PR = 1.53; 95% CI: 1.11-2.11; p = 0.010. Even in the age group of 10-14 years, <4 meals was related to higher prevalence of body mass index (PR = 1.33; 95% CI: 1.02-1.74; p = 0.032 and low-density lipoprotein (PR = 1.39; 95% CI: 1.03-1.87; p = 0.030 higher after adjustments. Conclusion: Lower frequency of meals was related to lower income in children and adolescents, larger number of sons in the family, and increased values of body mass index and low-density lipoprotein.

  18. Simple programmable voltage reference for low frequency noise measurements

    Science.gov (United States)

    Ivanov, V. E.; Chye, En Un

    2018-05-01

    The paper presents a circuit design of a low-noise voltage reference based on an electric double-layer capacitor, a microcontroller and a general purpose DAC. A large capacitance value (1F and more) makes it possible to create low-pass filter with a large time constant, effectively reducing low-frequency noise beyond its bandwidth. Choosing the optimum value of the resistor in the RC filter, one can achieve the best ratio between the transient time, the deviation of the output voltage from the set point and the minimum noise cut-off frequency. As experiments have shown, the spectral density of the voltage at a frequency of 1 kHz does not exceed 1.2 nV/√Hz the maximum deviation of the output voltage from the predetermined does not exceed 1.4 % and depends on the holding time of the previous value. Subsequently, this error is reduced to a constant value and can be compensated.

  19. A study of frequency effects on conductivity measurements

    International Nuclear Information System (INIS)

    Nurul Ain Ahmad Latif; Mahmood Dollah; Mohd Khidir Kamaron; Suaib Ibrahim

    2010-01-01

    In eddy current testing (ET), different measurement can be carry out through the selection of the test frequency. In conductivity measurement, the selection of eddy current test frequencies permits to select the specific material properties to be measured. The test frequency selected should be sufficient high that eddy current penetration is limited only to fraction of the test material thickness. This paper describes the effects of test frequency on the conductivity measurement. This experiment done by applying different values of test frequency which is 20 kHz, 100 kHz and 1 MHz. (author)

  20. Sharing of Alcohol-Related Content on Social Networking Sites: Frequency, Content, and Correlates.

    Science.gov (United States)

    Erevik, Eilin K; Torsheim, Torbjørn; Vedaa, Øystein; Andreassen, Cecilie S; Pallesen, Ståle

    2017-05-01

    The present study aimed to explore students' reports of their sharing of alcohol-related content on different social networking sites (i.e., frequency of sharing and connotations of alcohol-related posts), and to identify indicators of such posting. Students at the four largest institutions for higher education in Bergen, Norway, were invited to participate in an Internet-based survey. The sample size was 11,236 (a 39.4% response rate). The survey included questions about disclosure of alcohol-related content on social networking sites, alcohol use (using the Alcohol Use Disorders Identification Test), personality factors (using the Mini-IPIP), and demographic characteristics. Binary logistic regressions were used to analyze indicators of frequent sharing of alcohol-related content depicting positive and negative aspects of alcohol use. A majority of the students had posted alcohol-related content (71.0%), although few reported having done so frequently. Positive aspects of alcohol use (e.g., enjoyment or social community) were most frequently shared. Young, single, and extroverted students with high alcohol consumption were more likely to report frequent sharing of alcohol-related content. Positive attitudes toward posting alcohol-related content and reports of exposure to such content particularly increased the likelihood of one's own posting of alcohol-related content. Positive aspects of alcohol use seem to be emphasized on social networking sites. Sharing of alcohol-related content is associated with heightened alcohol use, which implies that such sites can be relevant for prevention agents. Social influence from social networking sites, such as exposure to others' alcohol-related content, is associated with one's own sharing of similar content.

  1. Relative validity of the food frequency questionnaire used to assess dietary intake in the Leiden Longevity Study

    NARCIS (Netherlands)

    Streppel, M.T.; Vries, de J.H.M.; Meyboom, S.; Beekman, M.; Craen, A.J.M.; Slagboom, P.E.; Feskens, E.J.M.

    2013-01-01

    Background - Invalid information on dietary intake may lead to false diet-disease associations. This study was conducted to examine the relative validity of the food frequency questionnaire (FFQ) used to assess dietary intake in the Leiden Longevity Study. Methods - A total of 128 men and women

  2. Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y., E-mail: thuzhangyu@foxmail.com; Huang, S. L., E-mail: huangsling@tsinghua.edu.cn; Wang, S.; Zhao, W. [State Key Laboratory of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China)

    2016-05-15

    The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert–Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of <1% and thus can act as a universal time-of-flight extraction method for narrowband Lamb wave detection signals.

  3. Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals

    International Nuclear Information System (INIS)

    Zhang, Y.; Huang, S. L.; Wang, S.; Zhao, W.

    2016-01-01

    The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert–Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of <1% and thus can act as a universal time-of-flight extraction method for narrowband Lamb wave detection signals.

  4. Quantifying Stability Using Frequency Domain Data from Wireless Inertial Measurement Units

    Directory of Open Access Journals (Sweden)

    Stephen Slaughter

    2013-06-01

    Full Text Available The quantification of gait stability can provide valuable information when evaluating subjects for age related and neuromuscular disease changes. Using tri-axial inertial measurement units (IMU for acceleration and rotational data provide a non-linear profile for this type of movement. As subjects traverse various surfaces representing decreasing stability, the different phasing of gait data make comparisons difficult. By converting from time to frequency domain data, the phase effects can be ignored, allowing for significant correlations. In this study, 12 subjects provided gait information over various surfaces while wearing an IMU. Instabilities were determined by comparing frequency domain data over less stable surfaces to frequency domain data of neural network (NN models representing the normal gait for any given participant. Time dependent data from 2 axes of acceleration and 2 axes of rotation were converted using a discrete Fourier transform (FFT algorithm. The data over less stable surfaces were compared to the normal gait NN model by averaging the Pearson product moment correlation (r values. This provided a method to quantify the decreased stability. Data showed progressively decreasing correlation coefficient values as subjects encountered progressively less stable surface environments. This methodology has allowed for the quantification of instability in gait situations for application in real-time fall prevention situations.

  5. Quantifying Stability Using Frequency Domain Data from Wireless Inertial Measurement Units

    Directory of Open Access Journals (Sweden)

    Stephen Slaughter

    2012-08-01

    Full Text Available The quantification of gait stability can provide valuable information when evaluating subjects for age related and neuromuscular disease changes. Using tri-axial inertial measurement units (IMU for acceleration and rotational data provide a non-linear profile for this type of movement. As subjects traverse various surfaces representing decreasing stability, the different phasing of gait data make comparisons difficult. By converting from time to frequency domain data, the phase effects can be ignored, allowing for significant correlations. In this study, 12 subjects provided gait information over various surfaces while wearing an IMU. Instabilities were determined by comparing frequency domain data over less stable surfaces to frequency domain data of neural network (NN models representing the normal gait for any given participant. Time dependent data from 2 axes of acceleration and 2 axes of rotation were converted using a discrete Fourier transform (FFT algorithm. The data over less stable surfaces were compared to the normal gait NN model by averaging the Pearson product moment correlation (r values. This provided a method to quantify the decreased stability. Data showed progressively decreasing correlation coefficient values as subjects encountered progressively less stable surface environments. This methodology has allowed for the quantification of instability in gait situations for application in real-time fall prevention situations.

  6. Social and Symbolic Capital in Firm Clusters: An empirical Investigation of Relational Resources and Value Creation

    DEFF Research Database (Denmark)

    Gretzinger, Susanne; Royer, Susanne

    Cluster initiatives are a popular instrument of public policy everywhere in the world. This development acknowledges that the organisational units that create added value are not isolated individual businesses, but networks of actors. Our research has the objective to better understand value...... creation of single firms embedded in clusters in terms of overlapping value adding webs of single firms. The main focus of the paper is on how to describe and operationalise and how to manage social and symbolic capital in clusters. The fact that the main source of value creation is rooted within networks...... raises the question of the impact of social capital on relational rents. The main objectives of this paper therefore are to investigate how value creation on the relational level of a cluster can be systematised to come to a better understanding of valuable resources on the cluster level. Empirically...

  7. Identification and Level 1 Damage Detection of the Z24 Highway Bridge by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Brincker, Rune; Andersen, P.; Cantieni, R.

    2001-01-01

    A series of 15 progressive damage tests were performed on a prestressed concrete highway bridge in Switzerland. The ambient response of the bridge was recorded for each damage case with a relatively large number of sensors. Changes in frequencies, damping ratios and MAC values were determined...

  8. A new tool for converting food frequency questionnaire data into nutrient and food group values: FETA research methods and availability.

    Science.gov (United States)

    Mulligan, Angela A; Luben, Robert N; Bhaniani, Amit; Parry-Smith, David J; O'Connor, Laura; Khawaja, Anthony P; Forouhi, Nita G; Khaw, Kay-Tee

    2014-03-27

    To describe the research methods for the development of a new open source, cross-platform tool which processes data from the European Prospective Investigation into Cancer and Nutrition Norfolk Food Frequency Questionnaire (EPIC-Norfolk FFQ). A further aim was to compare nutrient and food group values derived from the current tool (FETA, FFQ EPIC Tool for Analysis) with the previously validated but less accessible tool, CAFÉ (Compositional Analyses from Frequency Estimates). The effect of text matching on intake data was also investigated. Cross-sectional analysis of a prospective cohort study-EPIC-Norfolk. East England population (city of Norwich and its surrounding small towns and rural areas). Complete FFQ data from 11 250 men and 13 602 women (mean age 59 years; range 40-79 years). Nutrient and food group intakes derived from FETA and CAFÉ analyses of EPIC-Norfolk FFQ data. Nutrient outputs from FETA and CAFÉ were similar; mean (SD) energy intake from FETA was 9222 kJ (2633) in men, 8113 kJ (2296) in women, compared with CAFÉ intakes of 9175 kJ (2630) in men, 8091 kJ (2298) in women. The majority of differences resulted in one or less quintile change (98.7%). Only mean daily fruit and vegetable food group intakes were higher in women than in men (278 vs 212 and 284 vs 255 g, respectively). Quintile changes were evident for all nutrients, with the exception of alcohol, when text matching was not executed; however, only the cereals food group was affected. FETA produces similar nutrient and food group values to the previously validated CAFÉ but has the advantages of being open source, cross-platform and complete with a data-entry form directly compatible with the software. The tool will facilitate research using the EPIC-Norfolk FFQ, and can be customised for different study populations.

  9. The initial value problem as it relates to numerical relativity.

    Science.gov (United States)

    Tichy, Wolfgang

    2017-02-01

    Spacetime is foliated by spatial hypersurfaces in the 3+1 split of general relativity. The initial value problem then consists of specifying initial data for all fields on one such a spatial hypersurface, such that the subsequent evolution forward in time is fully determined. On each hypersurface the 3-metric and extrinsic curvature describe the geometry. Together with matter fields such as fluid velocity, energy density and rest mass density, the 3-metric and extrinsic curvature then constitute the initial data. There is a lot of freedom in choosing such initial data. This freedom corresponds to the physical state of the system at the initial time. At the same time the initial data have to satisfy the Hamiltonian and momentum constraint equations of general relativity and can thus not be chosen completely freely. We discuss the conformal transverse traceless and conformal thin sandwich decompositions that are commonly used in the construction of constraint satisfying initial data. These decompositions allow us to specify certain free data that describe the physical nature of the system. The remaining metric fields are then determined by solving elliptic equations derived from the constraint equations. We describe initial data for single black holes and single neutron stars, and how we can use conformal decompositions to construct initial data for binaries made up of black holes or neutron stars. Orbiting binaries will emit gravitational radiation and thus lose energy. Since the emitted radiation tends to circularize the orbits over time, one can thus expect that the objects in a typical binary move on almost circular orbits with slowly shrinking radii. This leads us to the concept of quasi-equilibrium, which essentially assumes that time derivatives are negligible in corotating coordinates for binaries on almost circular orbits. We review how quasi-equilibrium assumptions can be used to make physically well motivated approximations that simplify the elliptic

  10. Image Denoising Using Singular Value Difference in the Wavelet Domain

    Directory of Open Access Journals (Sweden)

    Min Wang

    2018-01-01

    Full Text Available Singular value (SV difference is the difference in the singular values between a noisy image and the original image; it varies regularly with noise intensity. This paper proposes an image denoising method using the singular value difference in the wavelet domain. First, the SV difference model is generated for different noise variances in the three directions of the wavelet transform and the noise variance of a new image is used to make the calculation by the diagonal part. Next, the single-level discrete 2-D wavelet transform is used to decompose each noisy image into its low-frequency and high-frequency parts. Then, singular value decomposition (SVD is used to obtain the SVs of the three high-frequency parts. Finally, the three denoised high-frequency parts are reconstructed by SVD from the SV difference, and the final denoised image is obtained using the inverse wavelet transform. Experiments show the effectiveness of this method compared with relevant existing methods.

  11. Study of extremely low frequency electromagnetic fields in infant incubators.

    Science.gov (United States)

    Cermáková, Eleonora

    2003-01-01

    The aim of the work was to present the results of measurements of extremely low frequency electromagnetic fields (ELF EMF), namely the magnetic flux density, inside infant incubators, and to compare these results with the data published by other authors who point out to a possible association between leukemia or other diseases observed in newborns kept in incubators after the birth and the ELF EMF exposure in the incubator. The measured magnetic flux densities were compared with the reference values for this frequency range indicated in the European Union (EU) recommendations. The repeated measurements in incubators were made with a calibrated magnetometer EFA 300 in the frequency range of 5-30 kHz. Effective values of magnetic flux densities of ELF EMF were determined taking account of the reference values. The results of many repeated measurements showing the values of magnetic flux density in modern incubators with plastic supporting frame, were compared with those obtained in old type incubators with iron skeleton. A power frequency of 50 Hz was detected in the incubator and the ELF EMF values were by over two orders lower than the EU reference values. The paper emphasizes the need to take a special care of newborns kept in incubators even if only the sub-reference values are detected. The EU reference values are intended for the adult human population. A baby in an incubator has much smaller dimensions, higher electric conductivity and maybe trigger another mechanism of response to ELF EMF than that indicated in this paper.

  12. A copyright protection scheme for digital images based on shuffled singular value decomposition and visual cryptography.

    Science.gov (United States)

    Devi, B Pushpa; Singh, Kh Manglem; Roy, Sudipta

    2016-01-01

    This paper proposes a new watermarking algorithm based on the shuffled singular value decomposition and the visual cryptography for copyright protection of digital images. It generates the ownership and identification shares of the image based on visual cryptography. It decomposes the image into low and high frequency sub-bands. The low frequency sub-band is further divided into blocks of same size after shuffling it and then the singular value decomposition is applied to each randomly selected block. Shares are generated by comparing one of the elements in the first column of the left orthogonal matrix with its corresponding element in the right orthogonal matrix of the singular value decomposition of the block of the low frequency sub-band. The experimental results show that the proposed scheme clearly verifies the copyright of the digital images, and is robust to withstand several image processing attacks. Comparison with the other related visual cryptography-based algorithms reveals that the proposed method gives better performance. The proposed method is especially resilient against the rotation attack.

  13. Frequency aspects of information transmission in a network of three western equity markets

    Science.gov (United States)

    Schmidbauer, Harald; Rösch, Angi; Uluceviz, Erhan

    2017-11-01

    Cycles in the behavior of stock markets have been widely documented. There is an increasing body of literature on whether stock markets anticipate business cycles or its turning points. Several recent studies assert that financial integration impacts positively on business cycle comovements of economies. We consider three western equity markets, represented by their respective stock indices: DJIA (USA), FTSE 100 (UK), and Euro Stoxx 50 (euro area). Connecting these three markets together via vector autoregressive processes in index returns, we construct ;propagation values; to measure and trace, on a daily basis, the relative importance of a market as a volatility creator within the network, where volatility is due to a return shock in a market. A cross-wavelet analysis reveals the joint frequency structure of pairs of the propagation value series, in particular whether or not two series tend to move in the same direction at a given frequency. Our main findings are: (i) From 2001 onwards, the daily propagation values of markets have been fluctuating much less than before, and high frequencies have become less pronounced; (ii) the European markets are in phase at business cycle frequency, while the US market is not in phase with either European market; (iii) in 2008, the euro area has taken over the leading role. This approach not only provides new insight into the time-dependent interplay of equity markets, but it can also replicate certain findings of traditional business cycle research, and it has the advantage of using only readily available stock market data.

  14. Function of One Regular Separable Relation Set Decided for the Minimal Covering in Multiple Valued Logic

    Directory of Open Access Journals (Sweden)

    Liu Yu Zhen

    2016-01-01

    Full Text Available Multiple-valued logic is an important branch of the computer science and technology. Multiple-valued logic studies the theory, multiple-valued circuit & multiple-valued system, and the applications of multiple-valued logic included.In the theory of multiple-valued logic, one primary and important problem is the completeness of function sets, which can be solved depending on the decision for all the precomplete sets(also called maximal closed sets of K-valued function sets noted by PK*, and another is the decision for Sheffer function, which can be totally solved by picking out all of the minimal covering of the precomplete sets. In the function structure theory of multi-logic, decision on Sheffer function is an important role. It contains structure and decision of full multi-logic and partial multi-logic. Its decision is closely related to decision of completeness of function which can be done by deciding the minimal covering of full multi-logic and partial-logic. By theory of completeness of partial multi-logic, we prove that function of one regular separable relation is not minimal covering of PK* under the condition of m = 2, σ = e.

  15. Frequency specificity and left-ear advantage of medial olivocochlear efferent modulation: a study based on stimulus frequency otoacoustic emission.

    Science.gov (United States)

    Xing, Dongjia; Gong, Qin

    2017-09-06

    The medial olivocochlear (MOC) bundle is an auditory nucleus that projects efferent nerve fibers to the outer hair cells (OHCs) for synaptic innervation. The aim of the present study was to investigate the possible existence of frequency and ear specificity in MOC efferent modulation, as well as how MOC activation influences cochlear tuning. Stimulus frequency otoacoustic emissions (SFOAEs) were used to study MOC efferent modulation. Therefore, the current experiment was designed to compare the degree of SFOAE suppression in the both ears of 20 individuals at 1, 2, 4, and 8 kHz. We also compared changes in Q10 values of SFOAE suppression tuning curves at 1, 2, and 4 kHz under contralateral acoustic stimulation (CAS) and no-CAS conditions. We observed a significant reduction in SFOAE magnitude in the CAS condition compared with the no-CAS condition at 1 and 2 kHz in the left ear. A significant difference in CAS suppression was also found between the left and right ears at 1 and 2 kHz, with larger CAS suppression in the left ear. CAS further produced a statistically significant increase in the Q10 value at 1 kHz and a significant reduction in Q10 values at 2 and 4 kHz. These findings suggest a left-ear advantage in terms of CAS-induced MOC efferent SFOAE suppression, with larger MOC efferent modulation for lower frequencies, and cochlear tuning was sharpened by means of MOC activation at lower frequencies and broadened at higher frequencies.

  16. 75 FR 81284 - Nationwide Use of High Frequency and Ultra High Frequency Active SONAR Technology; Draft...

    Science.gov (United States)

    2010-12-27

    ... Frequency and Ultra High Frequency Active SONAR Technology; Draft Programmatic Environmental Assessment and... Programmatic Environmental Assessment (PEA) for the Nationwide Use of High Frequency (HF) and Ultra High... potential impacts of each alternative on the human and natural environments. DATES: Comments and related...

  17. The relative contribution of genes and environment to alcohol use in early adolescents: are similar factors related to initiation of alcohol use and frequency of drinking?

    NARCIS (Netherlands)

    Poelen, Evelien A. P.; Derks, Eske M.; Engels, Rutger C. M. E.; van Leeuwe, Jan F. J.; Scholte, Ron H. J.; Willemsen, Gonneke; Boomsma, Dorret I.

    2008-01-01

    The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual differences in

  18. The Relative Contribution of Genes and Environment to Alcohol Use in Early Adolescents : Are Similar Factors Related to Initiation of Alcohol Use and Frequency of Drinking?

    NARCIS (Netherlands)

    Poelen, E.A.P.; Derks, E.M.; Engels, R.C.M.E.; Scholte, R.H.J.; Willemsen, A.H.M.; Boomsma, D.I.

    2008-01-01

    Background: The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual

  19. The relative contribution of genes and environment to alcohol use in early adolescents: Are similar factors related to initiation of alcohol use and frequency of drinking?

    NARCIS (Netherlands)

    Poelen, E.A.P.; Derks, E.M.; Engels, R.C.M.E.; Leeuwe, J.F.J.; Scholte, R.H.J.; Willemsen, G.; Boomsma, D.I.

    2008-01-01

    Background: The present study assessed the relative contribution of genes and environment to individual differences in initiation of alcohol use and frequency of drinking among early adolescents and examined the extent to which the same genetic and environmental factors influence both individual

  20. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry at the Cyclotron Frequency.

    Science.gov (United States)

    Nagornov, Konstantin O; Kozhinov, Anton N; Tsybin, Yury O

    2017-04-01

    The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω + ), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω + quantity. Here, we describe an experimental observation of a new resonant state, which is located close to the ω c frequency and is established because of azimuthally-dependent trapping electric fields of the recently developed ICR cells with narrow aperture detection electrodes. We show that in mass spectra, peaks close to ω + frequencies can be reduced to negligible levels relative to peaks close to ω c frequencies. Due to reduced errors with which the ω c quantity is obtained, the new resonance provides a means of cyclotron frequency measurements with precision greater than that achieved when ω + frequency peaks are employed. The described phenomenon may be considered for a development into an FT-ICR MS technology with increased mass accuracy for applications in basic research, life, and environmental sciences. Graphical Abstract ᅟ.

  1. Manufacturing technologies for ultrasonic transducers in a broad frequency range

    OpenAIRE

    Gebhardt, Sylvia; Hohlfeld, Kai; Günther, Paul; Neubert, Holger

    2018-01-01

    According to the application field, working frequency of ultrasonic transducers needs to be tailored to a certain value. Low frequency ultrasonic transducers with working frequencies of 1 kHz to 1 MHz are especially interesting for sonar applications, whereas high frequency ultrasonic transducers with working frequencies higher than 15 MHz are favorable for high-resolution imaging in biomedical and non-destructive evaluation. Conventional non-destructive testing devices and clinical ultrasoun...

  2. Maximum Entropy, Word-Frequency, Chinese Characters, and Multiple Meanings

    Science.gov (United States)

    Yan, Xiaoyong; Minnhagen, Petter

    2015-01-01

    The word-frequency distribution of a text written by an author is well accounted for by a maximum entropy distribution, the RGF (random group formation)-prediction. The RGF-distribution is completely determined by the a priori values of the total number of words in the text (M), the number of distinct words (N) and the number of repetitions of the most common word (kmax). It is here shown that this maximum entropy prediction also describes a text written in Chinese characters. In particular it is shown that although the same Chinese text written in words and Chinese characters have quite differently shaped distributions, they are nevertheless both well predicted by their respective three a priori characteristic values. It is pointed out that this is analogous to the change in the shape of the distribution when translating a given text to another language. Another consequence of the RGF-prediction is that taking a part of a long text will change the input parameters (M, N, kmax) and consequently also the shape of the frequency distribution. This is explicitly confirmed for texts written in Chinese characters. Since the RGF-prediction has no system-specific information beyond the three a priori values (M, N, kmax), any specific language characteristic has to be sought in systematic deviations from the RGF-prediction and the measured frequencies. One such systematic deviation is identified and, through a statistical information theoretical argument and an extended RGF-model, it is proposed that this deviation is caused by multiple meanings of Chinese characters. The effect is stronger for Chinese characters than for Chinese words. The relation between Zipf’s law, the Simon-model for texts and the present results are discussed. PMID:25955175

  3. Nature's starships. I. Observed abundances and relative frequencies of amino acids in meteorites

    International Nuclear Information System (INIS)

    Cobb, Alyssa K.; Pudritz, Ralph E.

    2014-01-01

    The class of meteorites called carbonaceous chondrites are examples of material from the solar system which have been relatively unchanged from the time of their initial formation. These meteorites have been classified according to the temperatures and physical conditions of their parent planetesimals. We collate available data on amino acid abundance in these meteorites and plot the concentrations of different amino acids for each meteorite within various meteorite subclasses. We plot average concentrations for various amino acids across meteorites separated by subclass and petrologic type. We see a predominance in the abundance and variety of amino acids in CM2 and CR2 meteorites. The range in temperature corresponding to these subclasses indicates high degrees of aqueous alteration, suggesting aqueous synthesis of amino acids. Within the CM2 and CR2 subclasses, we identify trends in relative frequencies of amino acids to investigate how common amino acids are as a function of their chemical complexity. These two trends (total abundance and relative frequencies) can be used to constrain formation parameters of amino acids within planetesimals. Our organization of the data supports an onion shell model for the temperature structure of planetesimals. The least altered meteorites (type 3) and their amino acids originated near cooler surface regions. The most active amino acid synthesis likely took place at intermediate depths (type 2). The most altered materials (type 1) originated furthest toward parent body cores. This region is likely too hot to either favor amino acid synthesis or for amino acids to be retained after synthesis.

  4. Dementia-Related Work Activities of Home Care Nurses and Aides: Frequency, Perceived Competence, and Continuing Education Priorities

    Science.gov (United States)

    Morgan, Debra G.; Kosteniuk, Julie G.; O'Connell, Megan E.; Dal Bello-Haas, Vanina; Stewart, Norma J.; Karunanayake, Chandima

    2016-01-01

    An understanding of the specific dementia learning needs of home care staff is needed to plan relevant continuing education (CE) programs and supports. The study's objective was to examine frequency and perceived competence in performing 20 dementia-related work activities, and identify CE priorities among home care staff. A cross-sectional survey…

  5. System and method for acquiring and inverting sparse-frequency data

    KAUST Repository

    Alkhalifah, Tariq Ali

    2017-01-01

    A method of imaging an object includes generating a plurality of mono-frequency waveforms and applying the plurality of mono-frequency waveforms to the object to be modeled. In addition, sparse mono-frequency data is recorded in response to the plurality of mono-frequency waveforms applied to the object to be modeled. The sparse mono-frequency data is cross-correlated with one or more source functions each having a frequency approximately equal to each of the plurality of mono-frequency waveforms to obtain monochromatic frequency data. The monochromatic frequency data is utilized in an inversion to converge a model to a minimum value.

  6. System and method for acquiring and inverting sparse-frequency data

    KAUST Repository

    Alkhalifah, Tariq Ali

    2017-11-30

    A method of imaging an object includes generating a plurality of mono-frequency waveforms and applying the plurality of mono-frequency waveforms to the object to be modeled. In addition, sparse mono-frequency data is recorded in response to the plurality of mono-frequency waveforms applied to the object to be modeled. The sparse mono-frequency data is cross-correlated with one or more source functions each having a frequency approximately equal to each of the plurality of mono-frequency waveforms to obtain monochromatic frequency data. The monochromatic frequency data is utilized in an inversion to converge a model to a minimum value.

  7. Frequency-Dependent Tidal Triggering of Low Frequency Earthquakes Near Parkfield, California

    Science.gov (United States)

    Xue, L.; Burgmann, R.; Shelly, D. R.

    2017-12-01

    The effect of small periodic stress perturbations on earthquake generation is not clear, however, the rate of low-frequency earthquakes (LFEs) near Parkfield, California has been found to be strongly correlated with solid earth tides. Laboratory experiments and theoretical analyses show that the period of imposed forcing and source properties affect the sensitivity to triggering and the phase relation of the peak seismicity rate and the periodic stress, but frequency-dependent triggering has not been quantitatively explored in the field. Tidal forcing acts over a wide range of frequencies, therefore the sensitivity to tidal triggering of LFEs provides a good probe to the physical mechanisms affecting earthquake generation. In this study, we consider the tidal triggering of LFEs near Parkfield, California since 2001. We find the LFEs rate is correlated with tidal shear stress, normal stress rate and shear stress rate. The occurrence of LFEs can also be independently modulated by groups of tidal constituents at semi-diurnal, diurnal and fortnightly frequencies. The strength of the response of LFEs to the different tidal constituents varies between LFE families. Each LFE family has an optimal triggering frequency, which does not appear to be depth dependent or systematically related to other known properties. This suggests the period of the applied forcing plays an important role in the triggering process, and the interaction of periods of loading history and source region properties, such as friction, effective normal stress and pore fluid pressure, produces the observed frequency-dependent tidal triggering of LFEs.

  8. The prognostic value of asymmetric laxity of the sacroiliac joints in pregnancy-related pelvic pain.

    NARCIS (Netherlands)

    Damen, L.; Buyruk, H.M.; Guler-Uysal, F.; Lotgering, F.K.; Snijders, C.J.; Stam, H.J.

    2002-01-01

    STUDY DESIGN: Prospective cohort study. OBJECTIVE: To determine the prognostic value of asymmetric laxity of the sacroiliac joints during pregnancy on pregnancy-related pelvic pain postpartum. SUMMARY OF BACKGROUND DATA: In a previous study, we observed a significant relation between asymmetric

  9. Elk Distributions Relative to Spring Normalized Difference Vegetation Index Values

    International Nuclear Information System (INIS)

    Smallidge, S.T.; Baker, T.T.; VanLeeuwen, D.; Gould, W.R.; Thompson, B.C.

    2010-01-01

    Rocky Mountain elk (Cervus elaphus) that winter near San Antonio Mountain in northern New Mexico provide important recreational and economic benefits while creating management challenges related to temporospatial variation in their spring movements. Our objective was to examine spring distributions of elk in relation to vegetative emergence as it progresses across the landscape as measured by remote sensing. Spring distributions of elk were closely associated with greater photosynthetic activity of spring vegetation in 2 of 3 years as determined using NDVI values derived from AVHRR datasets. Observed elk locations were up to 271% greater than expected in the category representing the most photosynthetic activity. This association was not observed when analyses at a finer geographic scale were conducted. Managers facing challenges involving human-wildlife interactions and land-use issues should consider environmental conditions that may influence variation in elk association with greener portions of the landscape.

  10. The effect of sampling rate and anti-aliasing filters on high-frequency response spectra

    Science.gov (United States)

    Boore, David M.; Goulet, Christine

    2013-01-01

    The most commonly used intensity measure in ground-motion prediction equations is the pseudo-absolute response spectral acceleration (PSA), for response periods from 0.01 to 10 s (or frequencies from 0.1 to 100 Hz). PSAs are often derived from recorded ground motions, and these motions are usually filtered to remove high and low frequencies before the PSAs are computed. In this article we are only concerned with the removal of high frequencies. In modern digital recordings, this filtering corresponds at least to an anti-aliasing filter applied before conversion to digital values. Additional high-cut filtering is sometimes applied both to digital and to analog records to reduce high-frequency noise. Potential errors on the short-period (high-frequency) response spectral values are expected if the true ground motion has significant energy at frequencies above that of the anti-aliasing filter. This is especially important for areas where the instrumental sample rate and the associated anti-aliasing filter corner frequency (above which significant energy in the time series is removed) are low relative to the frequencies contained in the true ground motions. A ground-motion simulation study was conducted to investigate these effects and to develop guidance for defining the usable bandwidth for high-frequency PSA. The primary conclusion is that if the ratio of the maximum Fourier acceleration spectrum (FAS) to the FAS at a frequency fsaa corresponding to the start of the anti-aliasing filter is more than about 10, then PSA for frequencies above fsaa should be little affected by the recording process, because the ground-motion frequencies that control the response spectra will be less than fsaa . A second topic of this article concerns the resampling of the digital acceleration time series to a higher sample rate often used in the computation of short-period PSA. We confirm previous findings that sinc-function interpolation is preferred to the standard practice of using

  11. [Relation between frequency modulation direction selectivity and forward masking of inferior collicular neurons: a study on in vivo intracellular recording in mice].

    Science.gov (United States)

    Fu, Zi-Ying; Zeng, Hong; Tang, Jia; Li, Jie; Li, Juan; Chen, Qi-Cai

    2013-06-25

    It has been reported that the frequency modulation (FM) or FM direction sensitivity and forward masking of central auditory neurons are related with the neural inhibition, but there are some arguments, because no direct evidence of inhibitory synaptic input was obtained in previous studies using extracellular recording. In the present study, we studied the relation between FM direction sensitivity and forward masking of the inferior collicular (IC) neurons using in vivo intracellular recordings in 20 Mus musculus Km mice. Thirty seven with complete data among 93 neurons were analyzed and discussed. There was an inhibitory area which consisted of inhibitory postsynaptic potentials (IPSP) at high frequency side of frequency tuning of up-sweep FM (FMU) sensitive neurons (n = 12) and at low frequency side of frequency tuning of down-sweep FM (FMD) selective neurons (n = 8), while there was no any inhibitory area at both sides of frequency tuning of non-FM sweep direction (FMN) sensitive neurons (n = 17). Therefore, these results show that the inhibitory area at low or high frequency side of frequency tuning is one of the mechanisms for forming FM sweep direction sensitivity of IC neurons. By comparison of forward masking produced by FMU and FMD sound stimuli in FMU, FMD and FMN neurons, the selective FM sounds could produce stronger forward masking than the non-selective in FMU and FMD neurons, while there was no forward masking difference between FMU and FMD stimuli in the FMN neurons. We suggest that the post-action potential IPSP is a potential mechanism for producing stronger forward masking in FMU and FMD neurons.

  12. Mate Value Discrepancy and Mate Retention Behaviors of Self and Partner.

    Science.gov (United States)

    Sela, Yael; Mogilski, Justin K; Shackelford, Todd K; Zeigler-Hill, Virgil; Fink, Bernhard

    2017-10-01

    This study investigated the relationship between perceived mate value discrepancy (i.e., the difference between an individual's mate value and their partner's mate value) and perceived frequency of mate retention performed by an individual relative to his or her partner. In two studies, participants in long-term, exclusive, sexual, heterosexual relationships reported their own, and their partner's, mate value and mate retention. Samples included 899 community members (Study 1) and 941 students and community members (Study 2). In Study 1, we documented that individuals with higher self-perceived short-term mate value, and who perceive their partner to have lower (vs. higher) short-term mate value, perform less frequent Benefit-Provisioning mate retention, controlling for the partner's Benefit-Provisioning mate retention. In Study 2, we documented that individuals who perceive that they could less easily replace their partner, and who perceive their partner could more (vs. less) easily replace them, perform more frequent mate retention (Benefit-Provisioning and Cost-Inflicting), controlling for the partner's mate retention. These results highlight the importance of assessing perceived discrepancies in mate value (notably, regarding the replaceability of self and partner with another long-term mate) and perceived mate retention behaviors of self, relative to partner, between men and women in long-term relationships. © 2016 Wiley Periodicals, Inc.

  13. The effect of group exercise frequency on health related quality of life in institutionalized elderly.

    Science.gov (United States)

    Rugbeer, Nivash; Ramklass, Serela; Mckune, Andrew; van Heerden, Johan

    2017-01-01

    The study aimed to determine the effect of group exercise frequency on health related quality of life in institutionalized elderly. One hundred participants were recruited for voluntary participation from five aged care facilities, with inclusion being based on the outcome of a medical assessment by a sports physician. A quasi-experimental design was used to compare the effect of a 12 week group exercise programme on two groups of participants using pre-test and post-test procedures. A significant difference was noted in social function post training 2X/week (MD = -13.85, 95% CI [-24.66, -3.38], p = 0.017, d = 0.674) and 3X/week (MD = -13.30, 95% CI [-21.81, -5.59], p = 0.003, d = 0.712) a week. Training 3X/week a week provided an additional benefit in vitality (MD = -7.55, 95% CI [-13.16, -1.91], p = 0.018, d =0. 379). Improvements in mental component summary scale post training 2X/week (MD = -4.08, 95% CI [-7.67, -0.42], p = 0.033, d = 0.425) and 3X/week (MD = -6.67, 95% CI [-10.92, -2.33], p = 0.005, d = 0.567) a week was further noted. Mental health and social health benefits can be obtained irrespective of exercise frequency 2X/week or 3X/week. The exercise intervention at a frequency 3X/ week was more effective in improving mental component summary due to a larger effect size obtained compared to the exercise frequency of 2X/week. Additional benefits in vitality were achieved by exercising 3X/week. This may assist the elderly in preserving their independence.

  14. Value dimensions of corporate culture of state-owned enterprise employees

    Directory of Open Access Journals (Sweden)

    Požega Željko

    2013-12-01

    Full Text Available This paper examines value dimensions of the organizational culture of employees in Hrvatska elektroprivreda d.d., a joint stock company wholly owned by the government of the Republic of Croatia, with the aim of identifying the corporate culture and value differences within the company in relation to employee gender, age and type of workplace. Hofstede’s research on organizational culture value dimensions forms the theoretical framework of this paper. Descriptive statistical methods, i.e., frequencies, comparison of means and ranking were used in the analysis. The results show a difference in values between older and younger employees, as well as between employees working in an office and those working in the field which leads to the conclusion that in this company there are different sub-cultural elements within a single corporate culture. Moreover, the results show that value dimensions of employees in Hrvatska elektroprivreda d.d. are somewhat different from earlier findings of Hofstede’s research into value dimensions of employees in the Republic of Croatia in that the power distance is lower; uncertainty avoidance remains relatively high; individualism of employees has risen considerably, the culture is still impregnated with feminine values and there is a high degree of long-term orientation of employees. The analysis of respondents’ answers indicates that personal time and family time are highly valued. In addition, physical working conditions, good working relations with immediate supervisors and good cooperation with colleagues were also rated high on the scale of importance. It was also found that the most important work objective was job security, and that personal steadiness, stability and persistence were most valued personal traits.

  15. Archetypal values of science and engineering staff in relation to their career orientations

    Directory of Open Access Journals (Sweden)

    Didi-Mari du Toit

    2012-04-01

    Research purpose: The objective of the study was to explore the relationship between individuals’ archetypal values (measured by the Pearson–Marr Archetype Indicator and career orientations (measured by the Career Orientations Inventory. The study also assessed the differences between race, gender, marital status, employment status and age groups regarding the archetypal values and career orientations of the individuals. Motivation for study: Career counsellors and industrial psychologists are increasingly required to explore new career guidance frameworks that are relevant and appropriate to the evolving nature of careers. Research design, approach and method: A quantitative survey was conducted. A non-probability sample of 207 voluntary participants employed within the science and engineering sector was obtained. Main findings: Correlational analyses revealed that the participants’ archetypal values related significantly to their career orientations. The various biographical groups differed significantly regarding their archetypal values and career orientations. Practical/managerial implications: The findings highlight the importance of understanding the deep-seated archetypal values that seem to explain the individuals’ career choices and decisions, and how these values differ regarding these choices and decisions. Contribution/value-add: The explanatory utility of the results may prove useful to enhance the individuals’ self-insight in their career choices and experiences. This study represents original research that contributes new knowledge to the field of career psychology and career counselling practices.

  16. An Early Model for Value and Sustainability in Health Information Exchanges: Qualitative Study

    Science.gov (United States)

    2018-01-01

    Background The primary value relative to health information exchange has been seen in terms of cost savings relative to laboratory and radiology testing, emergency department expenditures, and admissions. However, models are needed to statistically quantify value and sustainability and better understand the dependent and mediating factors that contribute to value and sustainability. Objective The purpose of this study was to provide a basis for early model development for health information exchange value and sustainability. Methods A qualitative study was conducted with 21 interviews of eHealth Exchange participants across 10 organizations. Using a grounded theory approach and 3.0 as a relative frequency threshold, 5 main categories and 16 subcategories emerged. Results This study identifies 3 core current perceived value factors and 5 potential perceived value factors—how interviewees predict health information exchanges may evolve as there are more participants. These value factors were used as the foundation for early model development for sustainability of health information exchange. Conclusions Using the value factors from the interviews, the study provides the basis for early model development for health information exchange value and sustainability. This basis includes factors from the research: fostering consumer engagement; establishing a provider directory; quantifying use, cost, and clinical outcomes; ensuring data integrity through patient matching; and increasing awareness, usefulness, interoperability, and sustainability of eHealth Exchange. PMID:29712623

  17. An Early Model for Value and Sustainability in Health Information Exchanges: Qualitative Study.

    Science.gov (United States)

    Feldman, Sue S

    2018-04-30

    The primary value relative to health information exchange has been seen in terms of cost savings relative to laboratory and radiology testing, emergency department expenditures, and admissions. However, models are needed to statistically quantify value and sustainability and better understand the dependent and mediating factors that contribute to value and sustainability. The purpose of this study was to provide a basis for early model development for health information exchange value and sustainability. A qualitative study was conducted with 21 interviews of eHealth Exchange participants across 10 organizations. Using a grounded theory approach and 3.0 as a relative frequency threshold, 5 main categories and 16 subcategories emerged. This study identifies 3 core current perceived value factors and 5 potential perceived value factors-how interviewees predict health information exchanges may evolve as there are more participants. These value factors were used as the foundation for early model development for sustainability of health information exchange. Using the value factors from the interviews, the study provides the basis for early model development for health information exchange value and sustainability. This basis includes factors from the research: fostering consumer engagement; establishing a provider directory; quantifying use, cost, and clinical outcomes; ensuring data integrity through patient matching; and increasing awareness, usefulness, interoperability, and sustainability of eHealth Exchange. ©Sue S Feldman. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 30.04.2018.

  18. Morphology of low-frequency waves in the solar wind and their relation to ground pulsations

    International Nuclear Information System (INIS)

    Odera, T.J.; Stuart, W.F.

    1986-01-01

    Three classes of low frequency waves (period range 20 to 80 s) were identified using data from the UCLA fluxgate magnetometer experiment on board the ISEE 2 spacecraft. These are continuous pulsations similar in type to Pc 3, band-limited oscillations distinguished by mixed period fluctuations, and relatively isolated wave bundles. The waves were preferentially observed when the interplanetary magnetic field (IMF) direction was sunward and were most common when the cone angle, i.e. the angle between IMF and the Sun-Earth line (thetasub(xB)) was often between 15 deg and 45 deg. Their frequency is proportional to the IMF magnitude. Comparison between the waves observed on board the ISEE 2 spacecraft and the Pc 3-4 recorded simultaneously at a mid-latitude ground station, Oulu (L = 4.5), showed that similarity of spectra of the waves in the spacecraft and on the ground was very rare and that correspondence between the events in space and on the ground was extremely low. (author)

  19. Improved Frequency Fluctuation Model for Spectral Line Shape Calculations in Fusion Plasmas

    International Nuclear Information System (INIS)

    Ferri, S.; Calisti, A.; Mosse, C.; Talin, B.; Lisitsa, V.

    2010-01-01

    A very fast method to calculate spectral line shapes emitted by plasmas accounting for charge particle dynamics and effects of an external magnetic field is proposed. This method relies on a new formulation of the Frequency Fluctuation Model (FFM), which yields to an expression of the dynamic line profile as a functional of the static distribution function of frequencies. This highly efficient formalism, not limited to hydrogen-like systems, allows to calculate pure Stark and Stark-Zeeman line shapes for a wide range of density, temperature and magnetic field values, which is of importance in plasma physics and astrophysics. Various applications of this method are presented for conditions related to fusion plasmas.

  20. Special frequencies and Lifshitz singularities in binary random harmonic chains

    International Nuclear Information System (INIS)

    Nieuwenhuizen, T.M.; Luck, J.M.; Canisius, J.; van Hemmen, J.L.; Ventevogel, W.J.

    1986-01-01

    The authors consider a one-dimensional chain of coupled harmonic oscillators; the mass of each atom is a random variable taking only two values (M or 1). They investigate the integrated density of states H(omega 2 ) near special frequencies: a given frequency omega/sub s/ with rational wavelength becomes special if the mass ratio M exceeds a certain critical value M/sub c/. They show that H has essential singularities of the types H/sub sg/∼ exp(-C 1 absolute value of omega 2 -omega/sub s/ 2 /sup 1/2/) or exp(-C 2 absolute value of omega 2 -omega/sub s/ 2 -1 ), according to the value of M and the sign of (omega 2 -omega/sub s/ 2 ). The Lifshitz singularity at the band edge is analyzed in the same way. In each case, the constant C 1 or C 2 is evaluated explicitly and compared with a vast amount of numerical work. All these exponential singularities are modulated by periodic amplitudes. The properties of the eigenfunctions with frequencies close to the special values are also discussed, and are illustrated by numerical data

  1. Direct excitation of a high frequency wave by a low frequency wave in a plasma

    International Nuclear Information System (INIS)

    Tanaka, Takayasu

    1993-01-01

    A new mechanism is presented of an excitation of a high frequency wave by a low frequency wave in a plasma. This mechanism works when the low frequency wave varies in time in a manner deviated from a usual periodic motion with a constant amplitude. The conversion rate is usually not large but the conversion is done without time delay after the variation of the low frequency wave. The Manley Rowe relation in the usual sense does not hold in this mechanism. This mechanism can excite also waves with same or lower frequencies. (author)

  2. Robust power system frequency control

    CERN Document Server

    Bevrani, Hassan

    2014-01-01

    This updated edition of the industry standard reference on power system frequency control provides practical, systematic and flexible algorithms for regulating load frequency, offering new solutions to the technical challenges introduced by the escalating role of distributed generation and renewable energy sources in smart electric grids. The author emphasizes the physical constraints and practical engineering issues related to frequency in a deregulated environment, while fostering a conceptual understanding of frequency regulation and robust control techniques. The resulting control strategi

  3. Development and Relative Validity of a Food Frequency Questionnaire to Assess Intakes of Total and Free Sugars in Australian Toddlers.

    Science.gov (United States)

    Devenish, Gemma; Mukhtar, Aqif; Begley, Andrea; Do, Loc; Scott, Jane

    2017-11-08

    Background : Dental research into early childhood caries is hindered by a lack of suitable dietary assessment tools that have been developed and validated for the population and outcomes of interest. The aim of this study was to develop and investigate the relative validity and reproducibility of the Study of Mothers' and Infants' Life Events Food Frequency Questionnaire (SMILE-FFQ), to assess the total and free sugars intakes of Australian toddlers. Methods : The SMILE-FFQ was designed to capture the leading dietary contributors to dental caries risk in toddlers aged 18-30 months via a proxy report. Ninety-five parents of Australian toddlers completed the questionnaire online before and after providing three 24-h recalls (24HR), collected on non-consecutive days using the multipass method. Total and free sugars were compared between the two SMILE-FFQ administrations and between each SMILE-FFQ and the 24HR using multiple statistical tests and standardised validity criteria. Correlation (Pearson), mean difference (Wilcoxon rank test) and Bland Altman analyses were conducted to compare absolute values, with cross-classification (Chi-Square and Weighted Kappa) used to compare agreement across tertiles. Results : All reproducibility tests showed good agreement except weighted kappa, which showed acceptable agreement. Relative validity tests revealed a mix of good and acceptable agreement, with total sugars performing better at the individual level than free sugars. Compared to the 24HR, the SMILE-FFQ tended to underestimate absolute values at lower levels and overestimate them at higher levels. Conclusions : The combined findings of the various tests indicate that the SMILE-FFQ performs comparably to the 24HR for assessing both total and free sugars among individuals, is most effective for ranking participants rather than determining absolute intakes, and is therefore suitable for use in observational studies of Australian toddlers.

  4. Stabilizing effects of hot electrons on low frequency plasma drift waves

    International Nuclear Information System (INIS)

    Huang Chaosong; Qiu Lijian; Ren Zhaoxing

    1988-01-01

    The MHD equation is used to study the stabilization of low frequency drift waves driven by density gradient of plasma in a hot electron plasma. The dispersion relation is derived, and the stabilizing effects of hot electrons are discussed. The physical mechanism for hot electron stabilization of the low frequency plasma perturbations is charge uncovering due to the hot electron component, which depends only on α, the ratio of N h /N i , but not on the value of β h . The hot electrons can reduce the growth rate of the interchange mode and drift wave driven by the plasma, and suppress the enomalous plasma transport caused by the drift wave. Without including the effectof β h , the stabilization of the interchange mode requires α≅2%, and the stabilization of the drift wave requires α≅40%. The theoretical analyses predict that the drift wave is the most dangerous low frequency instability in the hot electron plasma

  5. Ultralow frequency bridge for dielectric measurements: applications to electrects

    International Nuclear Information System (INIS)

    Slaets, J.

    1976-01-01

    The problem of U.L.F. (Ultra Low Frequency) dielectric relaxation is investigated. An experimental model is proposed for a bridge covering the range of 10 -3 Hz-10Hz, pased on phase shift measurements originally proposed by Van Turhout and collaborators. The main experimental problems are also analyzed with such U.L.F. measurements and describe its construction and performance. The theoretical correlation between U.L.F. dielectric relaxation and electret thermal stimulated currents is also investigated. A correction for the integral expression given by Turnhout and collaborators, is calculated in particular that takes into account the value of the activation energy in the relation between the two techniques.The correction is important for values of the activation energy below 0,5eV, which occur frequently in dielectric relaxation processes. (Author) [pt

  6. Structure and dielectric properties in the radio frequency range of polymer composites based on vanadium dioxide

    Directory of Open Access Journals (Sweden)

    Kolbunov V.R.

    2015-06-01

    Full Text Available Polymer composites with active fillers are recently considered to be promising materials for the design of new functional devices with controllable properties and are intensively investigated. Dielectric studies are one of the most effective methods for studying structural features and mechanisms of conductivity formation for this type of two-component systems. The paper presents research results of the dielectric characteristics in the range of radio frequency of 50 kHz — 10 MHz and temperature range of 30—60°C of polyethylene composites of vanadium dioxide with different volume fractions of filler. Two dispersion areas were found: a high-frequency area caused by the Maxwell charge separation on the boundaries of the polyethylene matrix — conductive filler of VI2 crystallites, and a low frequency area associated with the presence of the transition layer at this boundary. The relative permittivity of the composite has a tendency to a decrease in absolute value with increasing temperature. The analysis of the low-frequency dependence of the dielectric constant of the value of the filler’s volume fraction revealed that the investigated composite belongs to two-component statistical mixtures with a transition layer between the components.

  7. Areas V1 and V2 show microsaccade-related 3-4-Hz covariation in gamma power and frequency.

    Science.gov (United States)

    Lowet, E; Roberts, M J; Bosman, C A; Fries, P; De Weerd, P

    2016-05-01

    Neuronal gamma-band synchronization (25-80 Hz) in visual cortex appears sustained and stable during prolonged visual stimulation when investigated with conventional averages across trials. However, recent studies in macaque visual cortex have used single-trial analyses to show that both power and frequency of gamma oscillations exhibit substantial moment-by-moment variation. This has raised the question of whether these apparently random variations might limit the functional role of gamma-band synchronization for neural processing. Here, we studied the moment-by-moment variation in gamma oscillation power and frequency, as well as inter-areal gamma synchronization, by simultaneously recording local field potentials in V1 and V2 of two macaque monkeys. We additionally analyzed electrocorticographic V1 data from a third monkey. Our analyses confirm that gamma-band synchronization is not stationary and sustained but undergoes moment-by-moment variations in power and frequency. However, those variations are neither random and nor a possible obstacle to neural communication. Instead, the gamma power and frequency variations are highly structured, shared between areas and shaped by a microsaccade-related 3-4-Hz theta rhythm. Our findings provide experimental support for the suggestion that cross-frequency coupling might structure and facilitate the information flow between brain regions. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  8. The value of what others value : How personal and group values relate to pro-environmental attitudes and behaviours.

    NARCIS (Netherlands)

    Bouman, Thijs; Steg, Emmalina; Johnson, Stephanie

    2017-01-01

    Personal values are considered stable predictors of environmental attitudes and behaviours (e.g., Steg et al., 2014). In addition, group values are often used to characterize groups and compare them with each other (e.g., Schwartz & Bardi, 2001). However, only little is known about the influence of

  9. SRS Process Facility Significance Fire Frequency

    Energy Technology Data Exchange (ETDEWEB)

    Sarrack, A.G. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1995-10-01

    This report documents the method and assumptions of a study performed to determine a site generic process facility significant fire initiator frequency and explains the proper way this value should be used.

  10. SRS Process Facility Significance Fire Frequency

    International Nuclear Information System (INIS)

    Sarrack, A.G.

    1995-10-01

    This report documents the method and assumptions of a study performed to determine a site generic process facility significant fire initiator frequency and explains the proper way this value should be used

  11. Research on synchronization technology of frequency hopping communication system

    Science.gov (United States)

    Zhao, Xiangwu; Quan, Houde; Cui, Peizhang

    2018-05-01

    Frequency Hopping (FH) communication is a technology of spread spectrum communication. It has strong anti-interference, anti-interception and security capabilities, and has been widely applied in the field of communications. Synchronization technology is one of the most crucial technologies in frequency hopping communication. The speed of synchronization establishment and the reliability of synchronous system directly affect the performance of frequency hopping communication system. Therefore, the research of synchronization technology in frequency hopping communication has important value.

  12. Transient severe motion artifact related to gadoxetate disodium-enhanced liver MRI. Frequency and risk evaluation at a German institution

    Energy Technology Data Exchange (ETDEWEB)

    Well, Lennart; Rausch, Vanessa Hanna; Adam, Gerhard; Henes, Frank Oliver; Bannas, Peter [Univ. Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. for Diagnostic and Interventional Radiology and Nuclear Medicine

    2017-07-15

    Varying frequencies (5 - 18%) of contrast-related transient severe motion (TSM) imaging artifacts during gadoxetate disodium-enhanced arterial phase liver MRI have been reported. Since previous reports originated from the United States and Japan, we aimed to determine the frequency of TSM at a German institution and to correlate it with potential risk factors and previously published results. Two age- and sex-matched groups were retrospectively selected (gadoxetate disodium n = 89; gadobenate dimeglumine n = 89) from dynamic contrast-enhanced MRI examinations in a single center. Respiratory motion-related artifacts in non-enhanced and dynamic phases were assessed independently by two readers blinded to contrast agents on a 4-point scale. Scores of ≥3 were considered as severe motion artifacts. Severe motion artifacts in arterial phases were considered as TSM if scores in all other phases were < 3. Potential risk factors for TSM were evaluated via logistic regression analysis. For gadoxetate disodium, the mean score for respiratory motion artifacts was significantly higher in the arterial phase (2.2 ± 0.9) compared to all other phases (1.6 ± 0.7) (p < 0.05). The frequency of TSM was significantly higher with gadoxetate disodium (n = 19; 21.1 %) than with gadobenate dimeglumine (n = 1; 1.1%) (p < 0.001). The frequency of TSM at our institution is similar to some, but not all previously published findings. Logistic regression analysis did not show any significant correlation between TSM and risk factors (all p>0.05). We revealed a high frequency of TSM after injection of gadoxetate disodium at a German institution, substantiating the importance of a diagnosis-limiting phenomenon that so far has only been reported from the United States and Japan. In accordance with previous studies, we did not identify associated risk factors for TSM.

  13. Economic demand and essential value.

    Science.gov (United States)

    Hursh, Steven R; Silberberg, Alan

    2008-01-01

    The strength of a rat's eating reflex correlates with hunger level when strength is measured by the response frequency that precedes eating (B. F. Skinner, 1932a, 1932b). On the basis of this finding, Skinner argued response frequency could index reflex strength. Subsequent work documented difficulties with this notion because responding was affected not only by the strengthening properties of the reinforcer but also by the rate-shaping effects of the schedule. This article obviates this problem by measuring strength via methods from behavioral economics. This approach uses demand curves to map how reinforcer consumption changes with changes in the "price" different ratio schedules impose. An exponential equation is used to model these demand curves. The value of this exponential's rate constant is used to scale the strength or essential value of a reinforcer, independent of the scalar dimensions of the reinforcer. Essential value determines the consumption level to be expected at particular prices and the response level that will occur to support that consumption. This approach permits comparing reinforcers that differ in kind, contributing toward the goal of scaling reinforcer value. (c) 2008 APA, all rights reserved

  14. Validity and reproducibility of a food frequency questionnaire for dietary factors related to colorectal cancer

    OpenAIRE

    Tollosa, Daniel Nigusse; Van Camp, John; Huybrechts, Inge; Huybregts, Lieven; Van Loco, Joris; De Smet, Stefaan; Sterck, Ellen; Rabai, Celine; Van Hecke, Thomas; Vanhaecke, Lynn; Vossen, Els; Peeters, Marc; Lachat, Carl

    2017-01-01

    Abstract: Dietary factors play a major role in the development of colorectal cancer. This study evaluated the reproducibility and validity of a 109-food item Food Frequency Questionnaire (FFQ) to measure the consumption of foods and nutrients related to the development of colorectal cancer in a population aged 50 years in Flanders, Belgium. A semi-quantitative FFQ was administered two times in a period of two weeks to evaluate reproducibility (FFQ1 and FFQ2). The validity of the FFQ was asses...

  15. Broadband electromagnetic power harvester from vibrations via frequency conversion by impact oscillations

    International Nuclear Information System (INIS)

    Yuksek, N. S.; Almasri, M.; Feng, Z. C.

    2014-01-01

    In this paper, we propose an electromagnetic power harvester that uses a transformative multi-impact approach to achieve a wide bandwidth response from low frequency vibration sources through frequency-up conversion. The device consists of a pick-up coil, fixed at the free edge of a cantilever beam with high resonant frequency, and two cantilever beams with low excitation frequencies, each with an impact mass attached at its free edge. One of the two cantilevers is designed to resonate at 25 Hz, while the other resonates at 50 Hz within the range of ambient vibration frequency. When the device is subjected to a low frequency vibration, the two low-frequency cantilevers responded by vibrating at low frequencies, and thus their thick metallic masses made impacts with the high resonance frequency cantilever repeatedly at two locations. This has caused it along with the pick-up coil to oscillate, relative to the permanent magnet, with decaying amplitude at its resonance frequency, and results in a wide bandwidth response from 10 to 63 Hz at 2 g. A wide bandwidth response between 10–51 Hz and 10–58 Hz at acceleration values of 0.5 g and 2 g, respectively, were achieved by adjusting the impact cantilever frequencies closer to each other (25 Hz and 45 Hz). A maximum output power of 85 μW was achieved at 5 g at 30 Hz across a load resistor, 2.68 Ω.

  16. 75 FR 66125 - Federal Land Managers' Air Quality Related Values Work Group (FLAG)

    Science.gov (United States)

    2010-10-27

    ... pollutants that could affect the health and status of resources in areas managed by the three agencies... Work Group (FLAG) AGENCY: National Park Service, Interior. ACTION: Notice of availability of final... Public Comments document. The Federal Land Managers' Air Quality Related Values Work Group (FLAG) was...

  17. Transient Severe Motion Artifact Related to Gadoxetate Disodium-Enhanced Liver MRI: Frequency and Risk Evaluation at a German Institution.

    Science.gov (United States)

    Well, Lennart; Rausch, Vanessa Hanna; Adam, Gerhard; Henes, Frank Oliver; Bannas, Peter

    2017-07-01

    Purpose  Varying frequencies (5 - 18 %) of contrast-related transient severe motion (TSM) imaging artifacts during gadoxetate disodium-enhanced arterial phase liver MRI have been reported. Since previous reports originated from the United States and Japan, we aimed to determine the frequency of TSM at a German institution and to correlate it with potential risk factors and previously published results. Materials and Methods  Two age- and sex-matched groups were retrospectively selected (gadoxetate disodium n = 89; gadobenate dimeglumine n = 89) from dynamic contrast-enhanced MRI examinations in a single center. Respiratory motion-related artifacts in non-enhanced and dynamic phases were assessed independently by two readers blinded to contrast agents on a 4-point scale. Scores of ≥ 3 were considered as severe motion artifacts. Severe motion artifacts in arterial phases were considered as TSM if scores in all other phases were risk factors for TSM were evaluated via logistic regression analysis. Results  For gadoxetate disodium, the mean score for respiratory motion artifacts was significantly higher in the arterial phase (2.2 ± 0.9) compared to all other phases (1.6 ± 0.7) (p risk factors (all p > 0.05). Conclusion  We revealed a high frequency of TSM after injection of gadoxetate disodium at a German institution, substantiating the importance of a diagnosis-limiting phenomenon that so far has only been reported from the United States and Japan. In accordance with previous studies, we did not identify associated risk factors for TSM. Key Points:   · Gadoxetate disodium causes TSM in a relevant number of patients.. · The frequency of TSM is similar between the USA, Japan and Germany.. · To date, no validated risk factors for TSM could be identified.. Citation Format · Well L, Rausch VH, Adam G et al. Transient Severe Motion Artifact Related to Gadoxetate Disodium-Enhanced Liver MRI: Frequency and Risk Evaluation at a

  18. Value-impact assessment for resolution of generic safety issue 143 - availability of HVAC and chilled water systems

    Energy Technology Data Exchange (ETDEWEB)

    Daling, P.M.; Marler, J.E.; Vo, T.V. [Pacific Northwest Laboratory, Richland, WA (United States)] [and others

    1995-02-01

    The Pacific Northwest Laboratory (PNL), under contract to the U.S. Nuclear Regulatory Commission (NRC), has conducted an assessment of the values (benefits) and impacts (costs) associated with potential resolutions to Generic Issue 143, {open_quotes}Availability of Heating, Ventilation, and Air Conditioning (HVAC) and Chilled Water Systems.{close_quotes} This assessment was conducted to identify vulnerabilities related to failure of HVAC, chilled water and room cooling systems and develop estimates of the core damage frequencies and public risks associated with failures of these systems. This information was used to develop proposed resolution strategies to this generic issue and perform a value/impact assessment to determine their cost-effectiveness. Probabilistic risk assessments (PRAs) for four representative plants from the basis for the core damage frequency and public risk calculations. Internally-initiated core damage sequences as well as external events were considered. Three proposed resolution strategies were developed for this safety issue and it was determined that all three were not cost-effective. Additional evaluations were performed to develop {open_quotes}generic{close_quotes} insights on potential design-related vulnerabilities and potential high-frequency accident sequences that involve failures of HVAC/room cooling functions.

  19. Value-impact assessment for resolution of generic safety issue 143 - availability of HVAC and chilled water systems

    International Nuclear Information System (INIS)

    Daling, P.M.; Marler, J.E.; Vo, T.V.

    1995-01-01

    The Pacific Northwest Laboratory (PNL), under contract to the U.S. Nuclear Regulatory Commission (NRC), has conducted an assessment of the values (benefits) and impacts (costs) associated with potential resolutions to Generic Issue 143, open-quotes Availability of Heating, Ventilation, and Air Conditioning (HVAC) and Chilled Water Systems.close quotes This assessment was conducted to identify vulnerabilities related to failure of HVAC, chilled water and room cooling systems and develop estimates of the core damage frequencies and public risks associated with failures of these systems. This information was used to develop proposed resolution strategies to this generic issue and perform a value/impact assessment to determine their cost-effectiveness. Probabilistic risk assessments (PRAs) for four representative plants from the basis for the core damage frequency and public risk calculations. Internally-initiated core damage sequences as well as external events were considered. Three proposed resolution strategies were developed for this safety issue and it was determined that all three were not cost-effective. Additional evaluations were performed to develop open-quotes genericclose quotes insights on potential design-related vulnerabilities and potential high-frequency accident sequences that involve failures of HVAC/room cooling functions

  20. [A preliminary study of the work values of male nurses in Taiwan and related factors].

    Science.gov (United States)

    Hsu, Yu-Ying; Tang, Woung-Ru; Chang, Yue-Cune; Maa, Suh-Hwa

    2013-04-01

    Male nurses account for 1.08% of Taiwan's total professional nursing workforce. While work values are known to impact the practice of female nurses, the work values of male nurses have never been fully evaluated. The aim of this study was to explore the work values of male nurses in Taiwan and related factors. We applied a cross-sectional design that targeted all male nurses nationwide and used a structured questionnaire distributed by mail to collect data. Data were collected from 1,087 Taiwan-based male nurses with 745 valid responses. Mean score for overall work value was 2.78 (on a maximum scale of 4). Socio-demographic differences contributed to work value variance among respondents. Major factors of influence on work value included education, work unit, work position, work rank, salary, hospital classification, and reason for choosing a nursing career. This study found personal characteristics, occupational roles, job performance, and reason for choosing a career in nursing to all correlate strongly with work value.

  1. The Association between Valuing Popularity and Relational Aggression: The Moderating Effects of Actual Popularity and Physiological Reactivity to Exclusion

    Science.gov (United States)

    Shoulberg, Erin K.; Sijtsema, Jelle J.; Murray-Close, Dianna

    2011-01-01

    The association between having a reputation for valuing popularity and relational aggression was assessed in a sample of 126 female children and adolescents (mean age=12.43 years) at a 54-day residential summer camp for girls. Having a reputation for valuing popularity was positively related to relational aggression. This association was moderated…

  2. Task value profiles across subjects and aspirations to physical and IT-related sciences in the United States and Finland.

    Science.gov (United States)

    Chow, Angela; Eccles, Jacquelynne S; Salmela-Aro, Katariina

    2012-11-01

    Two independent studies were conducted to extend previous research by examining the associations between task value priority patterns across school subjects and aspirations toward the physical and information technology- (IT-) related sciences. Study 1 measured task values of a sample of 10th graders in the United States (N = 249) across (a) physics and chemistry, (b) math, and (c) English. Study 2 measured task values of a sample of students in the second year of high school in Finland (N = 351) across (a) math and science, (b) Finnish, and (c) the arts and physical education. In both studies, students were classified into groups according to how they ranked math and science in relation to the other subjects. Regression analyses indicated that task value group membership significantly predicted subsequent aspirations toward physical and IT-related sciences measured 1-2 years later. The task value groups who placed the highest priority on math and science were significantly more likely to aspire to physical and IT-related sciences than were the other groups. These findings provide support for the theoretical assumption regarding the predictive role of intraindividual hierarchical patterns of task values for subsequent preferences and choices suggested by the Eccles [Parsons] (1983) expectancy-value model.

  3. Non-training related causes of personnel performance problems: the role of organizational value systems

    International Nuclear Information System (INIS)

    Zaret, R.

    1987-01-01

    Training is frequently viewed as a panacea for all personnel related problems. Whenever an inexplicable incident occurs, training is verbalized by many as the solution, or worse, as the cause of the incident. All to frequently, training organizations are needlessly commissioned to develop some elaborate course, only to discover that the training is irrelevant to the problem. While training as a solution to an incident is socially acceptable, its' use clouds the real issue. The purpose of this paper is to emphasize that there are many reasons people do not perform, many of which are related to organizational culture or values. Values directly influence all activities which the authors are involved in, even to the extent of how they perceive their environment. They exert a strong, pervasive influence on what and how they perform

  4. Significance tests in mutagen screening: another method considering historical control frequencies

    International Nuclear Information System (INIS)

    Traut, H.

    1983-01-01

    Recently a method has been devised for testing the significance of the difference between a mutation frequency observed after chemical treatment or iradiation and the historical ('stable') control frequency. Another test is proposed serving the same purpose. Both methods are applied to several examples (experimental frequency versus historical control frequency). The results (P values) obtained agree well. (author)

  5. Variability of photovoltaic panels efficiency depending on the value of the angle of their inclination relative to the horizon

    Directory of Open Access Journals (Sweden)

    Majdak Marek

    2017-01-01

    Full Text Available The objective of this paper was to determine the relationship between the efficiency of photovoltaic panels and the value of the angle of their inclination relative to the horizon. For the purpose of experimental research have been done tests on the photovoltaic modules made of monocrystalline, polycrystalline and amorphous silicon. The experiment consisted of measurement of the voltage and current generated by photovoltaic panels at a known value of solar radiation and a specified resistance value determined by using resistor with variable value of resistance and known value of the angle of their inclination relative to the horizon.

  6. Instantaneous and Frequency-Warped Signal Processing Techniques for Auditory Source Separation.

    Science.gov (United States)

    Wang, Avery Li-Chun

    This thesis summarizes several contributions to the areas of signal processing and auditory source separation. The philosophy of Frequency-Warped Signal Processing is introduced as a means for separating the AM and FM contributions to the bandwidth of a complex-valued, frequency-varying sinusoid p (n), transforming it into a signal with slowly-varying parameters. This transformation facilitates the removal of p (n) from an additive mixture while minimizing the amount of damage done to other signal components. The average winding rate of a complex-valued phasor is explored as an estimate of the instantaneous frequency. Theorems are provided showing the robustness of this measure. To implement frequency tracking, a Frequency-Locked Loop algorithm is introduced which uses the complex winding error to update its frequency estimate. The input signal is dynamically demodulated and filtered to extract the envelope. This envelope may then be remodulated to reconstruct the target partial, which may be subtracted from the original signal mixture to yield a new, quickly-adapting form of notch filtering. Enhancements to the basic tracker are made which, under certain conditions, attain the Cramer -Rao bound for the instantaneous frequency estimate. To improve tracking, the novel idea of Harmonic -Locked Loop tracking, using N harmonically constrained trackers, is introduced for tracking signals, such as voices and certain musical instruments. The estimated fundamental frequency is computed from a maximum-likelihood weighting of the N tracking estimates, making it highly robust. The result is that harmonic signals, such as voices, can be isolated from complex mixtures in the presence of other spectrally overlapping signals. Additionally, since phase information is preserved, the resynthesized harmonic signals may be removed from the original mixtures with relatively little damage to the residual signal. Finally, a new methodology is given for designing linear-phase FIR filters

  7. Direct Load Control by AC Frequency Modulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; You, Shi

    2012-01-01

    Fine-grained under frequency load shedding called “demand as a frequency controlled reserve“ (DFCR) has been shown to be a promising method of providingfrequency regulation service from distributed loads [1]. Micro-grids with a large portion of intermittent renewable generation will benefit greatly...... from this technology because their low inertia. The paper proposes a operating procedure for utilizing DFCR loads for energy balancing, expanding DFCR’s well known role as a power balancing resource. The system operator can use DFCR for energy balancing by adjusting the frequency controller...... of generators to schedule off-nominal system frequency values. The feasibility of the proposed system is evaluated on an existing small island power system....

  8. Validity and reproducibility of a food frequency questionnaire for dietary factors related to colorectal cancer

    OpenAIRE

    Tollosa, Daniel Nigusse; Van Camp, John; Huybrechts, Inge; Huybregts, Lieven; Van Loco, Joris; De Smet, Stefaan; Sterck, Ellen; Rabâi, Céline; Van Hecke, Thomas; Vanhaecke, Lynn; Vossen, Els; Peeters, Marc; Lachat, Carl

    2017-01-01

    Dietary factors play a major role in the development of colorectal cancer. This study evaluated the reproducibility and validity of a 109-food item Food Frequency Questionnaire (FFQ) to measure the consumption of foods and nutrients related to the development of colorectal cancer in a population aged ≥50 years in Flanders, Belgium. A semi-quantitative FFQ was administered two times in a period of two weeks to evaluate reproducibility (FFQ1 and FFQ2). The validity of the FFQ was assessed by co...

  9. RELATION BETWEEN BACKGROUND VARIABLES, VALUES AND CORPORATE SOCIAL RESPONSIBILITY

    Directory of Open Access Journals (Sweden)

    Maria del Rosario González-Rodriguez

    2016-02-01

    Full Text Available Consumer perception of corporate social responsibility (CSR can be directly influenced by individual value structures. This research aims to provide new knowledge regarding the relationship between basic human values and the public’s perception of CSR. It focuses on the values of higher education students and their views regarding a particular corporate social initiative. The study reveals that social, educational, and economic circumstances influence human values. Those values in turn influence why different students perceive CSR differently. These findings are relevant to companies as they provide a more detailed understanding of why certain consumer groups perceive certain CSR initiatives the way that they do. They also suggest that universities should increase their awareness of the importance of integrating human values and CSR in the curricula of future business managers and social leaders.

  10. Preoperative screening: value of previous tests.

    Science.gov (United States)

    Macpherson, D S; Snow, R; Lofgren, R P

    1990-12-15

    To determine the frequency of tests done in the year before elective surgery that might substitute for preoperative screening tests and to determine the frequency of test results that change from a normal value to a value likely to alter perioperative management. Retrospective cohort analysis of computerized laboratory data (complete blood count, sodium, potassium, and creatinine levels, prothrombin time, and partial thromboplastin time). Urban tertiary care Veterans Affairs Hospital. Consecutive sample of 1109 patients who had elective surgery in 1988. At admission, 7549 preoperative tests were done, 47% of which duplicated tests performed in the previous year. Of 3096 previous results that were normal as defined by hospital reference range and done closest to the time of but before admission (median interval, 2 months), 13 (0.4%; 95% CI, 0.2% to 0.7%), repeat values were outside a range considered acceptable for surgery. Most of the abnormalities were predictable from the patient's history, and most were not noted in the medical record. Of 461 previous tests that were abnormal, 78 (17%; CI, 13% to 20%) repeat values at admission were outside a range considered acceptable for surgery (P less than 0.001, frequency of clinically important abnormalities of patients with normal previous results with those with abnormal previous results). Physicians evaluating patients preoperatively could safely substitute the previous test results analyzed in this study for preoperative screening tests if the previous tests are normal and no obvious indication for retesting is present.

  11. Resonance frequency analysis

    Directory of Open Access Journals (Sweden)

    Rajiv K Gupta

    2011-01-01

    Full Text Available Initial stability at the placement and development of osseointegration are two major issues for implant survival. Implant stability is a mechanical phenomenon which is related to the local bone quality and quantity, type of implant, and placement technique used. The application of a simple, clinically applicable, non-invasive test to assess implant stability and osseointegration is considered highly desirable. Resonance frequency analysis (RFA is one of such techniques which is most frequently used now days. The aim of this paper was to review and analyze critically the current available literature in the field of RFA, and to also discuss based on scientific evidence, the prognostic value of RFA to detect implants at risk of failure. A search was made using the PubMed database to find all the literature published on "Resonance frequency analysis for implant stability" till date. Articles discussed in vivo or in vitro studies comparing RFA with other methods of implant stability measurement and articles discussing its reliability were thoroughly reviewed and discussed. A limited number of clinical reports were found. Various studies have demonstrated the feasibility and predictability of the technique. However, most of these articles are based on retrospective data or uncontrolled cases. Randomized, prospective, parallel-armed longitudinal human trials are based on short-term results and long-term follow up are still scarce in this field. Nonetheless, from available literature, it may be concluded that RFA technique evaluates implant stability as a function of stiffness of the implant bone interface and is influenced by factors such as bone type, exposed implant height above the alveolar crest. Resonance frequency analysis could serve as a non-invasive diagnostic tool for detecting the implant stability of dental implants during the healing stages and in subsequent routine follow up care after treatment. Future studies, preferably randomized

  12. Value Priorities and Behavior: Applying a Theory of Integrated Value Systems

    Directory of Open Access Journals (Sweden)

    Shalom Schwartz

    2016-02-01

    Full Text Available A major goal of research on values has been to relate individual differences in value priorities to differences in attitudes, behavior and background variables. Past research most commonly adopted one of two approaches. Much research has selected a few single target values whose priorities were postulated to associate with the attitude, behavior and background variable of interest and then examined empirical relationships. Other research has been more exploratory.It has related lists of values to various other variables and then discussed the significant associations that emerge. The focus on relationships with single values make both these approaches insatisfying. My work has sought to overcome those approaches.It has derived what may be a nearly comprehensive set of different motivational types of values, recognized across cultures. Each value type is represented by a number of single values that are combined to form relatively reliable indexes of values priorities. Value systems can be treated as integrated wholes in their relations with behaviors and, thereby, encourages researches to abandom the prevailing single-values approaches. 

  13. Evaluation of activity-based costing versus resource-based relative value costing.

    Science.gov (United States)

    Berlin, Mark F; Smith, Tommy H

    2004-01-01

    Activity-based costing (ABC) and relative value units costing (RVU) are two approaches that a practice manager can use to determine the cost of physician services. Each costing approach has features that provide distinction as well as differentiation in the cost estimates that are estimated. This paper will provide cost estimates under each approach along with cost estimates under a hybrid approach that merges features from each costing approach known as the ABC-RVU costing technique. A comparison of the results will be provided.

  14. Event group importance measures for top event frequency analyses

    International Nuclear Information System (INIS)

    1995-01-01

    Three traditional importance measures, risk reduction, partial derivative, nd variance reduction, have been extended to permit analyses of the relative importance of groups of underlying failure rates to the frequencies of resulting top events. The partial derivative importance measure was extended by assessing the contribution of a group of events to the gradient of the top event frequency. Given the moments of the distributions that characterize the uncertainties in the underlying failure rates, the expectation values of the top event frequency, its variance, and all of the new group importance measures can be quantified exactly for two familiar cases: (1) when all underlying failure rates are presumed independent, and (2) when pairs of failure rates based on common data are treated as being equal (totally correlated). In these cases, the new importance measures, which can also be applied to assess the importance of individual events, obviate the need for Monte Carlo sampling. The event group importance measures are illustrated using a small example problem and demonstrated by applications made as part of a major reactor facility risk assessment. These illustrations and applications indicate both the utility and the versatility of the event group importance measures

  15. Event group importance measures for top event frequency analyses

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-31

    Three traditional importance measures, risk reduction, partial derivative, nd variance reduction, have been extended to permit analyses of the relative importance of groups of underlying failure rates to the frequencies of resulting top events. The partial derivative importance measure was extended by assessing the contribution of a group of events to the gradient of the top event frequency. Given the moments of the distributions that characterize the uncertainties in the underlying failure rates, the expectation values of the top event frequency, its variance, and all of the new group importance measures can be quantified exactly for two familiar cases: (1) when all underlying failure rates are presumed independent, and (2) when pairs of failure rates based on common data are treated as being equal (totally correlated). In these cases, the new importance measures, which can also be applied to assess the importance of individual events, obviate the need for Monte Carlo sampling. The event group importance measures are illustrated using a small example problem and demonstrated by applications made as part of a major reactor facility risk assessment. These illustrations and applications indicate both the utility and the versatility of the event group importance measures.

  16. Gambling frequency and symptoms of attention-deficit hyperactivity disorder in relation to problem gambling among Swedish adolescents: a population-based study.

    Science.gov (United States)

    Hellström, Charlotta; Wagner, Philippe; Nilsson, Kent W; Leppert, Jerzy; Åslund, Cecilia

    2017-06-01

    To investigate the associations between gambling frequency, attention-deficit hyperactivity disorder (ADHD) symptoms, and problem gambling among adolescent boys and girls. One hypothesis was that adolescents with increased ADHD symptoms have a higher frequency of gambling compared to adolescents with fewer ADHD symptoms. A population-based sample of adolescents (aged 15-18 years) completed a questionnaire on demographics, gambling habits, ADHD symptoms, and problematic gambling; 1412 adolescents (from 4440 sampled) with gambling experience were included in the final sample. A zero-inflated negative binomial regression analysis revealed that increased ADHD symptoms, higher gambling frequency, and higher age were associated with lower odds for being non-susceptible to gambling problems. Moreover, gambling frequency interacted with ADHD symptoms in predicting probability of being non-susceptible to gambling problems. However, when analysing those already susceptible to problem gambling, ADHD symptoms did not modify the effect of gambling frequency on the expected magnitude of gambling problems. In susceptible individuals, problem gambling increased with both increased ADHD symptoms and increased gambling frequency, but the level of problems due to gambling frequency did not change depending on the ADHD symptom level. There was an interaction effect between sex and gambling frequency in relation to gambling problems. Adolescents with ADHD symptoms seem to be more sensitive to gambling, in terms of being susceptible to developing gambling problems. However, once susceptible, adolescents with ADHD symptoms are affected by gambling frequency similarly to other susceptible participants.

  17. Frequency and severity of transfusion-related acute lung injury--German haemovigilance data (2006-2007).

    Science.gov (United States)

    Keller-Stanislawski, B; Reil, A; Günay, S; Funk, M B

    2010-01-01

    In an observational cohort study (2006-2007) the Paul-Ehrlich-Institut collected epidemiological data to investigate the frequency and causes of TRALI. Diagnosis of TRALI was confirmed according to criteria of the European Haemovigilance Network. Subsequent testing of white blood cell antibodies (WBC-Ab) against HLA or human neutrophil alloantigens was performed. Of a total of 187 reported TRALI cases, 44 could be confirmed consisting of 35 cases of antibody-mediated TRALI and nine cases of non-immune-mediated TRALI. Eight of 44 affected patients (18%) had a fatal outcome, seven cases with WBC-Ab positive plasma donors and one case with red blood cell donors. WBC antibodies were found in one male and 39 female donors. In 34 female donors, a history of pregnancy was confirmed. WBC-Ab positive donors presented four HLA class I antibodies, 15 HLA class II antibodies, 13 HLA class I and class II antibodies, one HNA-2a, and seven HNA-3a antibodies. WBC antibodies matching with recipient antigens were found exclusively in 28 female donors; 26 FFP donors, one platelet donor and one red blood cell donor. Reporting frequency of immune-mediated TRALI was 1:66,000 for fresh frozen plasma, 1:2.86 million for red blood cell concentrates and 1:420,000 for platelet concentrates. Reporting frequency of TRALI-related fatalities was 1:285,000 for FFP. Haemovigilance data show the significance of female donors with a history of pregnancy for the development of antibody-mediated TRALI. Manufacturing of FFP from male plasma and female donor screening for WBC-Ab could represent preventive measures.

  18. 19 CFR Appendix to Part 146 - Guidelines for Determining Producibility and Relative Values for Oil Refinery Zones

    Science.gov (United States)

    2010-04-01

    ... status crude oil is required, because the law requires the value used for computing the relative value to... Crude Consumed 518,451×$.105 = $54,437 Volumetric Gain 21,602 Avg. Value/Barrel Crude Consumed=$16,756,891÷518,451=$32.321 (8) This example shows volumetric gain of 21,602 mbbls. However, in that PF was...

  19. The national public's values and interests related to the Arctic National Wildlife Refuge: A computer content analysis

    Science.gov (United States)

    David N. Bengston; David P. Fan; Roger Kaye

    2010-01-01

    This study examined the national public's values and interests related to the Arctic National Wildlife Refuge. Computer content analysis was used to analyze more than 23,000 media stories about the refuge from 1995 through 2007. Ten main categories of Arctic National Wildlife Refuge values and interests emerged from the analysis, reflecting a diversity of values,...

  20. Cantilever Beam Natural Frequencies in Centrifugal Inertia Field

    Science.gov (United States)

    Jivkov, V. S.; Zahariev, E. V.

    2018-03-01

    In the advanced mechanical science the well known fact is that the gravity influences on the natural frequencies and modes even for the vertical structures and pillars. But, the condition that should be fulfilled in order for the gravity to be taken into account is connected with the ration between the gravity value and the geometrical cross section inertia. The gravity is related to the earth acceleration but for moving structures there exist many other acceleration exaggerated forces and such are forces caused by the centrifugal accelerations. Large rotating structures, as wind power generators, chopper wings, large antennas and radars, unfolding space structures and many others are such examples. It is expected, that acceleration based forces influence on the structure modal and frequency properties, which is a subject of the present investigations. In the paper, rotating beams are subject to investigations and modal and frequency analysis is carried out. Analytical dependences for the natural resonances are derived and their dependences on the angular velocity and centrifugal accelerations are derived. Several examples of large rotating beams with different orientations of the rotating shaft are presented. Numerical experiments are conducted. Time histories of the beam tip deflections, that depict the beam oscillations are presented.

  1. Smoking cessation: Exploration of perceived technology-related information value.

    Science.gov (United States)

    Reychav, Iris; McHaney, Roger; Hirak, Eyal; Merker, Ben

    2018-01-01

    This study describes a unique approach to information transfer affecting the perceived value of this information and related impact on smoker behavior. Data were collected via survey, sampling approximately 120 participants. An online survey tool was used for the survey creation, data collection and monitoring. Another online tool was used by participants to create short animation videos as a means of increasing their engagement with information in an experiential fashion. Study findings included that the process experienced by the test group was influential and facilitated participants' change of mind regarding enrollment in a smoking cessation workshop. This was partly attributable to the IKEA effect. The study provides evidence that a change in habits crucial to improve health and enhance positive lifestyle choices can be stimulated through active engagement with artifact creation in a technology-mediated environment.

  2. IDENTIFYING ANTHROPOGENIC METALLIC POLLUTANTS USING FREQUENCY DEPENDENT MAGNETIC SUSCEPTIBILITY MEASUREMENTS IN ABUJA METROPOLIS

    Directory of Open Access Journals (Sweden)

    Jatto S. Solomon

    2017-07-01

    Full Text Available Soil formed from lithological and weathering processes of parent rocks generally exhibit paramagnetic properties due to some minerals contained in the rocks and thus have significant value of magnetic susceptibility. This susceptibility arising from the influence of the parent rocks tend to mask anthropogenic grains pollutants released into the environment by human activities. Hence, it becomes difficult to identify the effect of the lithological and anthropogenic magnetic susceptibility in complex soil found in urban areas. The superparamagnetic effect of lithological soil, a single state domain and multi-domain state of anthropogenic grains can easily be investigated by frequency dependent measurements where readings between 0-2.0% indicates the absence of lithological influence, 2.0-8.0% indicates multi-domain grains or mixture of both single stage and multi-domian grains and 8.0-12% indicates the superparamagntic (SP grain from lithological origin. In this work frequency dependent measurements were carried out along 5 selected road networks within the 5 districts of Abuja phase 1. Measurements were also carried out in 379 random points at the surface and depth of 40.0cm to investigate the distribution of anthropogenic grains in Abuja metropolis using the Bartington susceptibility meter. Frequency dependent measurements along the selected road networks indicate0-3.0% immediately after the roads pavement to a distance of about 3.0m from the road, indicating that the magnetic susceptibility arise mostly form anthropogenic influence rather than lithological processes. At the distance of 3.0-8.0m, frequency dependent values of about 3.0-8.0% were recorded, indicating mixture of both superparamagnetic and multi-domain grains. Beyond the distance of 8.0m, the frequency dependent values are mostly above 8.0.0%, indicating virtually all SP grains. The spatial distribution frequency dependent surface map shows the presence of anthropogenic grains in

  3. Low-level contrast statistics of natural images can modulate the frequency of event-related potentials (ERP in humans

    Directory of Open Access Journals (Sweden)

    Masoud Ghodrati

    2016-12-01

    Full Text Available Humans are fast and accurate in categorizing complex natural images. It is, however, unclear what features of visual information are exploited by brain to perceive the images with such speed and accuracy. It has been shown that low-level contrast statistics of natural scenes can explain the variance of amplitude of event-related potentials (ERP in response to rapidly presented images. In this study, we investigated the effect of these statistics on frequency content of ERPs. We recorded ERPs from human subjects, while they viewed natural images each presented for 70 ms. Our results showed that Weibull contrast statistics, as a biologically plausible model, explained the variance of ERPs the best, compared to other image statistics that we assessed. Our time-frequency analysis revealed a significant correlation between these statistics and ERPs’ power within theta frequency band (~3-7 Hz. This is interesting, as theta band is believed to be involved in context updating and semantic encoding. This correlation became significant at ~110 ms after stimulus onset, and peaked at 138 ms. Our results show that not only the amplitude but also the frequency of neural responses can be modulated with low-level contrast statistics of natural images and highlights their potential role in scene perception.

  4. Model validity and frequency band selection in operational modal analysis

    Science.gov (United States)

    Au, Siu-Kui

    2016-12-01

    Experimental modal analysis aims at identifying the modal properties (e.g., natural frequencies, damping ratios, mode shapes) of a structure using vibration measurements. Two basic questions are encountered when operating in the frequency domain: Is there a mode near a particular frequency? If so, how much spectral data near the frequency can be included for modal identification without incurring significant modeling error? For data with high signal-to-noise (s/n) ratios these questions can be addressed using empirical tools such as singular value spectrum. Otherwise they are generally open and can be challenging, e.g., for modes with low s/n ratios or close modes. In this work these questions are addressed using a Bayesian approach. The focus is on operational modal analysis, i.e., with 'output-only' ambient data, where identification uncertainty and modeling error can be significant and their control is most demanding. The approach leads to 'evidence ratios' quantifying the relative plausibility of competing sets of modeling assumptions. The latter involves modeling the 'what-if-not' situation, which is non-trivial but is resolved by systematic consideration of alternative models and using maximum entropy principle. Synthetic and field data are considered to investigate the behavior of evidence ratios and how they should be interpreted in practical applications.

  5. Elite Female Business Students in China and Norway: Job-Related Values and Preferences

    Science.gov (United States)

    Nordhaug, Odd; Gooderham, Paul; Zhang, Xian; Liu, Yali; Birkelund, Gunn Elisabeth

    2010-01-01

    The focus of this paper is on the work-related values, preferences, and future expectations among female students at two elite business schools in China and Norway. The paper argues that while gender theory predicts no significant differences between these two groups, both cultural and economic development theory imply fundamental differences. The…

  6. Q-value of the superallowed {beta} decay of {sup 62}Ga

    Energy Technology Data Exchange (ETDEWEB)

    Eronen, T. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland)]. E-mail: tommi.eronen@phys.jyu.fi; Elomaa, V. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Hager, U. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Hakala, J. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Jokinen, A. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Kankainen, A. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Moore, I. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Penttilae, H. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Rahaman, S. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Rinta-Antila, S. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Saastamoinen, A. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Sonoda, T. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Aystoe, J. [Department of Physics, P.O. Box 35 (YFL), FIN-40014 University of Jyvaeskylae (Finland); Bey, A.; Blank, B.; Canchel, G.; Dossat, C.; Giovinazzo, J.; Matea, I. [Centre d' Etudes Nucleaires de Bordeaux-Gradignan, Le Haut-Vigneau, F-33175 Gradignan cedex (France); Adimi, N. [Faculte de Physique, USTHB, BP32, El Alia, 16111 Bab Ezzouar, Alger (Algeria)

    2006-05-11

    Masses of the radioactive isotopes {sup 62}Ga, {sup 62}Zn and {sup 62}Cu have been measured at the JYFLTRAP facility with a relative precision of better than 1.8x10{sup -8}. A Q{sub EC} value of (9181.07{+-}0.54) keV for the superallowed decay of {sup 62}Ga is obtained from the measured cyclotron frequency ratios of {sup 62}Ga-{sup 62}Zn, {sup 62}Ga-{sup 62}Ni and {sup 62}Zn-{sup 62}Ni ions. The resulting Ft-value supports the validity of the conserved vector current hypothesis (CVC). The mass excess values measured were (-51986.5{+-}1.0) keV for {sup 62}Ga (-61167.9{+-}0.9) keV for {sup 62}Zn and (-62787.2{+-}0.9) keV for {sup 62}Cu.

  7. Low frequency turbulence, particle and heat transport in the Wisconsin levitated octupole

    International Nuclear Information System (INIS)

    Garner, H.R.

    1982-01-01

    Low frequency turbulence in the drift frequency range and its relation to the observed particle transport in the Wisconsin Levitated Octupole has been studied with a microwave scattering apparatus. The experimental parameters were T/sub e/ approx. T/sub i/ 13 cm -3 , 200 G < B/sub p-average/ < 1.25 kG. The effect of shear on the transport was studied by the addition of a small toroidal field. By matching experimentally measured density profiles to those given by numerical solutions of the transport equations, diffusion coefficients were obtained. Time dependent density fluctuation spectra were measured with an 8 mm microwave scattering diagnostic to correlate the drift wave portion of the spectrum with the observed diffusion. The density fluctuation spectrum of low frequency (1 kHz < ω < 6 MHz) turbulence was measured for several values of perpendicular wavenumber, k/sub perpendicular to/. Electron heat transport was studied by fitting experimentally measured electron temperature profiles to those predicted by numerical solutions of electron energy transport equation

  8. High frequency breakdown voltage

    International Nuclear Information System (INIS)

    Chu, Thanh Duy.

    1992-03-01

    This report contains information about the effect of frequency on the breakdown voltage of an air gap at standard pressure and temperature, 76 mm Hg and O degrees C, respectively. The frequencies of interest are 47 MHz and 60 MHz. Additionally, the breakdown in vacuum is briefly considered. The breakdown mechanism is explained on the basis of collision and ionization. The presence of the positive ions produced by ionization enhances the field in the gap, and thus determines the breakdown. When a low-frequency voltage is applied across the gap, the breakdown mechanism is the same as that caused by the DC or static voltage. However, when the frequency exceeds the first critical value f c , the positive ions are trapped in the gap, increasing the field considerably. This makes the breakdown occur earlier; in other words, the breakdown voltage is lowered. As the frequency increases two decades or more, the second critical frequency, f ce , is reached. This time the electrons start being trapped in the gap. Those electrons that travel multiple times across the gap before reaching the positive electrode result in an enormous number of electrons and positive ions being present in the gap. The result is a further decrease of the breakdown voltage. However, increasing the frequency does not decrease the breakdown voltage correspondingly. In fact, the associated breakdown field intensity is almost constant (about 29 kV/cm).The reason is that the recombination rate increases and counterbalances the production rate, thus reducing the effect of the positive ions' concentration in the gap. The theory of collision and ionization does not apply to the breakdown in vacuum. It seems that the breakdown in vacuum is primarily determined by the irregularities on the surfaces of the electrodes. Therefore, the effect of frequency on the breakdown, if any, is of secondary importance

  9. INFLUENCE OF CLIENT RELATIONS ON THE VALUE OF COMPANY INTELLECTUAL CAPITAL

    Directory of Open Access Journals (Sweden)

    NICOLETA RADNEANTU

    2014-10-01

    Full Text Available Since the last decades of the twentieth century, we can see a major transformation of human society as a whole, manifested by both socially and economically changes, which practically led to the emergence of a new reality - knowledge-based society. We cannot talk about a "capitalisation model of intangible assets in the context of the knowledge society" as long as knowledge, intellectual capital, customer relations, relationships with suppliers, alliances, partnerships, etc., - elements that contribute most the market value of companies - are not properly recognized, measured, recorded and reported. Therefore, in this paper we have treated the issue of intangible assets in the context of the knowledge society, insisting on: managers' perceptions of knowledge-based organizations and companies in the Top 100 by market capitalization, listed on the Bucharest Stock Exchange (BVB on customer relations.

  10. Different Mode of Afferents Determines the Frequency Range of High Frequency Activities in the Human Brain: Direct Electrocorticographic Comparison between Peripheral Nerve and Direct Cortical Stimulation.

    Directory of Open Access Journals (Sweden)

    Katsuya Kobayashi

    Full Text Available Physiological high frequency activities (HFA are related to various brain functions. Factors, however, regulating its frequency have not been well elucidated in humans. To validate the hypothesis that different propagation modes (thalamo-cortical vs. cortico-coritcal projections, or different terminal layers (layer IV vs. layer II/III affect its frequency, we, in the primary somatosensory cortex (SI, compared HFAs induced by median nerve stimulation with those induced by electrical stimulation of the cortex connecting to SI. We employed 6 patients who underwent chronic subdural electrode implantation for presurgical evaluation. We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response and N80 (late response of somatosensory evoked potentials (HFA(SEP(N20 and HFA(SEP(N80 and compared those overriding N1 and N2 (first and second responses of cortico-cortical evoked potentials (HFA(CCEP(N1 and HFA(CCEP(N2. HFA(SEP(N20 showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1 had its power peak in the frequency below 200 Hz. Different propagation modes and/or different terminal layers seemed to determine HFA frequency. Since HFA(CCEP(N1 and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

  11. Reduced gamma frequency in the medial frontal cortex of aged rats during behavior and rest: implications for age-related behavioral slowing.

    Science.gov (United States)

    Insel, Nathan; Patron, Lilian A; Hoang, Lan T; Nematollahi, Saman; Schimanski, Lesley A; Lipa, Peter; Barnes, Carol A

    2012-11-14

    Age-related cognitive and behavioral slowing may be caused by changes in the speed of neural signaling or by changes in the number of signaling steps necessary to achieve a given function. In the mammalian cortex, neural communication is organized by a 30-100 Hz "gamma" oscillation. There is a putative link between the gamma frequency and the speed of processing in a neural network: the dynamics of pyramidal neuron membrane time constants suggest that synaptic integration is framed by the gamma cycle, and pharmacological slowing of gamma also slows reaction times on behavioral tasks. The present experiments identify reductions in a robust 40-70 Hz gamma oscillation in the aged rat medial frontal cortex. The reductions were observed in the form of local field potentials, later peaks in fast-spiking neuron autocorrelations, and delays in the spiking of inhibitory neurons following local excitatory signals. Gamma frequency did not vary with movement speed, but rats with slower gamma also moved more slowly. Gamma frequency age differences were not observed in hippocampus. Hippocampal CA1 fast-spiking neurons exhibited interspike intervals consistent with a fast (70-100 Hz) gamma frequency, a pattern maintained across theta phases and theta frequencies independent of fluctuations in the average firing rates of the neurons. We propose that an average lengthening of the cortical 15-25 ms gamma cycle is one factor contributing to age-related slowing and that future attempts to offset cognitive declines will find a target in the response of fast-spiking inhibitory neurons to excitatory inputs.

  12. Iodine-frequency-stabilized laser diode and displacement-measuring interferometer based on sinusoidal phase modulation

    Science.gov (United States)

    Duong, Quang Anh; Vu, Thanh Tung; Higuchi, Masato; Wei, Dong; Aketagawa, Masato

    2018-06-01

    We propose a sinusoidal phase modulation method to achieve both the frequency stabilization of an external-cavity laser diode (ECLD) to an 127I2 saturated absorption transition near 633 nm and displacement measurement using a Mach–Zehnder interferometer. First, the frequency of the ECLD is stabilized to the b 21 hyperfine component of the P(33) 6-3 transition of 127I2 by combining sinusoidal phase modulation by an electro-optic modulator and frequency modulation spectroscopy by chopping the pump beam using an acousto-optic modulator. Even though a small modulation index of m  =  3.768 rad is utilized, a relative frequency stability of 10‑11 order is obtained over a sampling time of 400 s. Secondly, the frequency-stabilized ECLD is applied as a light source to a Mach–Zehnder interferometer. From the two consecutive modulation harmonics (second and third orders) involved in the interferometer signal, the displacement of the moving mirror is determined for four optical path differences (L 0  =  100, 200, 500, and 1000 mm). The measured modulation indexes for the four optical path differences coincide with the designated value (3.768 rad) within 0.5%. Compared with the sinusoidal frequency modulation Michelson interferometer (Vu et al 2016 Meas. Sci. Technol. 27 105201) which was demonstrated by some of the same authors of this paper, the phase modulation Mach–Zhender interferometer could fix the modulation index to a constant value for the four optical path differences. In this report, we discuss the measurement principle, experimental system, and results.

  13. Multiscale singular value manifold for rotating machinery fault diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Yi; Lu, BaoChun; Zhang, Deng Feng [School of Mechanical Engineering, Nanjing University of Science and Technology,Nanjing (United States)

    2017-01-15

    Time-frequency distribution of vibration signal can be considered as an image that contains more information than signal in time domain. Manifold learning is a novel theory for image recognition that can be also applied to rotating machinery fault pattern recognition based on time-frequency distributions. However, the vibration signal of rotating machinery in fault condition contains cyclical transient impulses with different phrases which are detrimental to image recognition for time-frequency distribution. To eliminate the effects of phase differences and extract the inherent features of time-frequency distributions, a multiscale singular value manifold method is proposed. The obtained low-dimensional multiscale singular value manifold features can reveal the differences of different fault patterns and they are applicable to classification and diagnosis. Experimental verification proves that the performance of the proposed method is superior in rotating machinery fault diagnosis.

  14. Uncertainties Related to Extreme Event Statistics of Sewer System Surcharge and Overflow

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Johansen, C.; Thorndahl, Søren Liedtke

    2005-01-01

    Today it is common practice - in the major part of Europe - to base design of sewer systems in urban areas on recommended minimum values of flooding frequencies related to either pipe top level, basement level in buildings or level of road surfaces. Thus storm water runoff in sewer systems is only...... proceeding in an acceptable manner, if flooding of these levels is having an average return period bigger than a predefined value. This practice is also often used in functional analysis of existing sewer systems. If a sewer system can fulfil recommended flooding frequencies or not, can only be verified...... by performing long term simulations - using a sewer flow simulation model - and draw up extreme event statistics from the model simulations. In this context it is important to realize that uncertainties related to the input parameters of rainfall runoff models will give rise to uncertainties related...

  15. Haplotype frequency distribution for 7 microsatellites in chromosome 8 and 11 in relation to the metabolic syndrome in four ethnic groups: Tehran Lipid and Glucose Study.

    Science.gov (United States)

    Daneshpour, Maryam Sadat; Hosseinzadeh, Nima; Zarkesh, Maryam; Azizi, Fereidoun

    2012-03-01

    Different variants of haplotype frequencies may lead to various frequencies of the same variants in individuals with drug resistance and disease susceptibility at the population level. In this study, the haplotype frequencies of 4 STR loci including the D8S1132, D8S1779, D8S514 and D8S1743, and 3 STR loci including D11S1304, D11S1998 and D11S934 were investigated in 563 individuals of four Iranian ethnic groups in the capital city of Iran, Tehran. One hundred thirty subjects had the metabolic syndrome. Haplotype frequencies of all markers were calculated. There were significant differences in the haplotype frequencies in short and long alleles between the metabolic affected subjects and controls. In addition, haplotype frequencies were significant in the four ethnic groups in both chromosomes 8 and 11. Our findings show a relation between the short allele of D8S1743 in all related haplotype frequencies of subjects with metabolic syndrome. These findings may require more studies of some candidate genes, including the lipoprotein lipase gene, in this chromosomal region. Copyright © 2011. Published by Elsevier B.V.

  16. Nonlinear Filtering Effects of Reservoirs on Flood Frequency Curves at the Regional Scale: RESERVOIRS FILTER FLOOD FREQUENCY CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Li, Hong-Yi; Leung, Lai-Yung; Yigzaw, Wondmagegn Y.; Zhao, Jianshi; Lu, Hui; Deng, Zhiqun; Demissie, Yonas; Bloschl, Gunter

    2017-10-01

    Anthropogenic activities, e.g., reservoir operation, may alter the characteristics of Flood Frequency Curve (FFC) and challenge the basic assumption of stationarity used in flood frequency analysis. This paper presents a combined data-modeling analysis of the nonlinear filtering effects of reservoirs on the FFCs over the contiguous United States. A dimensionless Reservoir Impact Index (RII), defined as the total upstream reservoir storage capacity normalized by the annual streamflow volume, is used to quantify reservoir regulation effects. Analyses are performed for 388 river stations with an average record length of 50 years. The first two moments of the FFC, mean annual maximum flood (MAF) and coefficient of variations (CV), are calculated for the pre- and post-dam periods and compared to elucidate the reservoir regulation effects as a function of RII. It is found that MAF generally decreases with increasing RII but stabilizes when RII exceeds a threshold value, and CV increases with RII until a threshold value beyond which CV decreases with RII. The processes underlying the nonlinear threshold behavior of MAF and CV are investigated using three reservoir models with different levels of complexity. All models capture the non-linear relationships of MAF and CV with RII, suggesting that the basic flood control function of reservoirs is key to the non-linear relationships. The relative roles of reservoir storage capacity, operation objectives, available storage prior to a flood event, and reservoir inflow pattern are systematically investigated. Our findings may help improve flood-risk assessment and mitigation in regulated river systems at the regional scale.

  17. Reliabilty worth: Development of a relationship with outage magnitude, duration and frequency

    International Nuclear Information System (INIS)

    Turner, F.P.P.; Katrichak, A.M.; Dwyer, A.; Edwards, D.; Ibrahim, A.

    1994-01-01

    British Columbia Hydro's Worth Project Team was founded to determine values for reliability for reference in evaluation of investment and operating decisions. Work to date has produced key preliminary values for specific outages and concepts for the shape of the relationship between value and these determinates of reliability worth, frequency, magnitude and duration. These values and concepts are described. The values are developed through an iterative, trial and refinement approach. The approach incorporates direct input from customers, common sense and judgement, and micro- and macro-economic concepts. Reliability worth values for reduced or prevented outages are presented for residential, commercial, small industrial and mixed sectors and various outage durations. Reliability worth values were obtained through customer surveys. Limitations of the reliability worth value are numerous and are listed. Study of cost vs magnitude of interruption using microeconomic models has shown that costly system improvements to reduce the possibility of widespread outages may not be justified. The case of exceptionally large area outages (blackouts) is examined. The cost vs frequency relationship was examined in terms of the economic concept of utility or satisfaction. Different loss/frequency characteristics are demonstrated for different customer classes. Customer value for reduced outage duration is expressed in a curve with flatter slope than that for eliminated outages. 2 refs., 6 figs

  18. Auto-identification of engine fault acoustic signal through inverse trigonometric instantaneous frequency analysis

    Directory of Open Access Journals (Sweden)

    Dayong Ning

    2016-03-01

    Full Text Available The acoustic signals of internal combustion engines contain valuable information about the condition of engines. These signals can be used to detect incipient faults in engines. However, these signals are complex and composed of a faulty component and other noise signals of background. As such, engine conditions’ characteristics are difficult to extract through wavelet transformation and acoustic emission techniques. In this study, an instantaneous frequency analysis method was proposed. A new time–frequency model was constructed using a fixed amplitude and a variable cycle sine function to fit adjacent points gradually from a time domain signal. The instantaneous frequency corresponds to single value at any time. This study also introduced instantaneous frequency calculation on the basis of an inverse trigonometric fitting method at any time. The mean value of all local maximum values was then considered to identify the engine condition automatically. Results revealed that the mean of local maximum values under faulty conditions differs from the normal mean. An experiment case was also conducted to illustrate the availability of the proposed method. Using the proposed time–frequency model, we can identify engine condition and determine abnormal sound produced by faulty engines.

  19. The association between valuing popularity and relational aggression : The moderating effects of actual popularity and physiological reactivity to exclusion

    NARCIS (Netherlands)

    Shoulberg, Erin K.; Sijtsema, Jelle J.; Murray-Close, Dianna

    The association between having a reputation for valuing popularity and relational aggression was assessed in a sample of 126 female children and adolescents (mean age = 12.43 years) at a 54-day residential summer camp for girls. Having a reputation for valuing popularity was positively related to

  20. Monopole and dipole estimation for multi-frequency sky maps by linear regression

    Science.gov (United States)

    Wehus, I. K.; Fuskeland, U.; Eriksen, H. K.; Banday, A. J.; Dickinson, C.; Ghosh, T.; Górski, K. M.; Lawrence, C. R.; Leahy, J. P.; Maino, D.; Reich, P.; Reich, W.

    2017-01-01

    We describe a simple but efficient method for deriving a consistent set of monopole and dipole corrections for multi-frequency sky map data sets, allowing robust parametric component separation with the same data set. The computational core of this method is linear regression between pairs of frequency maps, often called T-T plots. Individual contributions from monopole and dipole terms are determined by performing the regression locally in patches on the sky, while the degeneracy between different frequencies is lifted whenever the dominant foreground component exhibits a significant spatial spectral index variation. Based on this method, we present two different, but each internally consistent, sets of monopole and dipole coefficients for the nine-year WMAP, Planck 2013, SFD 100 μm, Haslam 408 MHz and Reich & Reich 1420 MHz maps. The two sets have been derived with different analysis assumptions and data selection, and provide an estimate of residual systematic uncertainties. In general, our values are in good agreement with previously published results. Among the most notable results are a relative dipole between the WMAP and Planck experiments of 10-15μK (depending on frequency), an estimate of the 408 MHz map monopole of 8.9 ± 1.3 K, and a non-zero dipole in the 1420 MHz map of 0.15 ± 0.03 K pointing towards Galactic coordinates (l,b) = (308°,-36°) ± 14°. These values represent the sum of any instrumental and data processing offsets, as well as any Galactic or extra-Galactic component that is spectrally uniform over the full sky.

  1. Self-regulatory mode (locomotion and assessment), well-being (subjective and psychological), and exercise behavior (frequency and intensity) in relation to high school pupils' academic achievement.

    Science.gov (United States)

    Garcia, Danilo; Jimmefors, Alexander; Mousavi, Fariba; Adrianson, Lillemor; Rosenberg, Patricia; Archer, Trevor

    2015-01-01

    Background. Self-regulation is the procedure implemented by an individual striving to reach a goal and consists of two inter-related strategies: assessment and locomotion. Moreover, both subjective and psychological well-being along exercise behaviour might also play a role on adolescents academic achievement. Method. Participants were 160 Swedish high school pupils (111 boys and 49 girls) with an age mean of 17.74 (sd = 1.29). We used the Regulatory Mode Questionnaire to measure self-regulation strategies (i.e., locomotion and assessment). Well-being was measured using Ryff's Psychological Well-Being Scales short version, the Temporal Satisfaction with Life Scale, and the Positive Affect and Negative Affect Schedule. Exercise behaviour was self-reported using questions pertaining to frequency and intensity of exercise compliance. Academic achievement was operationalized through the pupils' mean value of final grades in Swedish, Mathematics, English, and Physical Education. Both correlation and regressions analyses were conducted. Results. Academic achievement was positively related to assessment, well-being, and frequent/intensive exercise behaviour. Assessment was, however, negatively related to well-being. Locomotion on the other hand was positively associated to well-being and also to exercise behaviour. Conclusions. The results suggest a dual (in)direct model to increase pupils' academic achievement and well-being-assessment being directly related to higher academic achievement, while locomotion is related to frequently exercising and well-being, which in turn, increase academic achievement.

  2. Customers’ Perceptions of Value in Relation to Hotels in Gauteng, South Africa

    Directory of Open Access Journals (Sweden)

    Vongani Ntimane

    2017-04-01

    Full Text Available This study is based on the premise that the hospitality industry operates within a highly competitive business environment and that the creation of customer-perceived value is a business component that concerns the striving to gain competitive advantage in terms of financial success, customer satisfaction and loyalty. The aim of the study was to explore the hotel value attributes perceived as being most important by hotel customers. To achieve the objective, a quantitative study design was employed, in terms of which data were purposively and conveniently collected by means of a survey questionnaire that was administered to hotel guests staying in 3- to 5-star hotels. The findings revealed that hotel customers tend to attach a high degree of importance to the issue of value for money, whereas the appearance of the hotel was least important to them of the tourism-related characteristics about which they were asked. Overall, the study found that hotels in Gauteng generally provide service that is satisfactory to their customers, but that the remaining challenge for hoteliers lies in their ability to sustain such levels of satisfaction through continuous employee motivation and skills development.

  3. Integrated InP frequency discriminator for Phase-modulated microwave photonic links.

    Science.gov (United States)

    Fandiño, J S; Doménech, J D; Muñoz, P; Capmany, J

    2013-02-11

    We report the design, fabrication and characterization of an integrated frequency discriminator on InP technology for microwave photonic phase modulated links. The optical chip is, to the best of our knowledge, the first reported in an active platform and the first to include the optical detectors. The discriminator, designed as a linear filter in intensity, features preliminary SFDR values the range between 67 and 79 dB.Hz(2/3) for signal frequencies in the range of 5-9 GHz limited, in principle, by the high value of the optical losses arising from the use of several free space coupling devices in our experimental setup. As discussed, these losses can be readily reduced by the use of integrated spot-size converters improving the SFDR by 17.3 dB (84-96 dB.Hz(2/3)). Further increase up to a range of (104-116 dB.Hz(2/3)) is possible by reducing the system noise eliminating the EDFA employed in the setup and using a commercially available laser source providing higher output power and lower relative intensity noise. Other paths for improvement requiring a filter redesign to be linear in the optical field are also discussed.

  4. Preparation, crystal structure, and dielectric characterization of Li2W2O7 ceramic at RF and microwave frequency range

    Directory of Open Access Journals (Sweden)

    Jinwu Chen

    2017-02-01

    Full Text Available Single phase Li2W2O7 with anorthic structure was prepared by the conventional solid-state reaction method at 550∘C and the anorthic structure was stable up to 660∘C. The dielectric properties at radio frequency (RF and microwave frequency range were characterized. The sample sintered at 640∘C exhibited the optimum microwave dielectric properties with a relative permittivity of 12.2, a quality factor value of 17,700GHz (at 9.8GHz, and a temperature coefficient of the resonant frequency of −232ppm/∘C as well as a high relative density ∼94.1%. Chemical compatibility measurement indicated Li2W2O7 did not react with aluminum electrodes when sintered at 640∘C for 4h.

  5. The relative frequencies of causes of widespread ground-glass opacity: A retrospective cohort

    International Nuclear Information System (INIS)

    Hewitt, Michael G.; Miller, Wallace T.; Reilly, Thomas J.; Simpson, Scott

    2014-01-01

    Highlights: • The most common cause of widespread ground-glass opacities is hydrostatic pulmonary edema. • Associated findings such as air-trapping and centrilobular nodules are highly specific for hypersensitivity pneumonitis. • The clinical setting (outpatient versus inpatient) will alter the order of the differential diagnosis. - Abstract: Purpose: The purpose of our study was to determine the relative frequencies of causes of widespread ground-glass opacity (GGO) in an unselected, consecutive patient population and to identify any associated imaging findings that can narrow or reorganize the differential. Materials and methods: The study was approved by the center's IRB and is HIPPA compliant. Cases with widespread GGO in the radiology report were identified by searching the Radiology Information System. Medical records and CT scan examinations were reviewed for the causes of widespread GGO. Associations between a less dominant imaging finding and a particular diagnosis were analyzed with the chi square test. Our study group consisted of 234 examinations with 124 women and 110 men and a mean age of 53.7 years. Results: A cause was established in 204 (87.2%) cases. Hydrostatic pulmonary edema was most common with 131 cases (56%). Interstitial lung diseases (ILD) were the next most common, most often hypersensitivity pneumonitis (HP) (n = 12, 5%) and connective tissue disease related ILD (n = 7, 3%). Infection accounted for 5% (12 cases). A few miscellaneous diseases accounted for 5 cases (2.1%). The combination of septal thickening and pleural effusions had a specificity of 0.91 for hydrostatic pulmonary edema (P < .001) while centrilobular nodules and air trapping had a specificity of 1.0 for HP. In 24 (10.2%) patients, increased opacification from expiration was incorrectly interpreted as representing widespread ground glass opacity. The relative frequency of disease dramatically changed according to the setting. In the inpatient setting, diffuse

  6. The relative frequencies of causes of widespread ground-glass opacity: A retrospective cohort

    Energy Technology Data Exchange (ETDEWEB)

    Hewitt, Michael G., E-mail: Mike_hewitt@me.com; Miller, Wallace T., E-mail: Wallace.miller@uphs.upenn.edu; Reilly, Thomas J., E-mail: thomasjreilly@comcast.net; Simpson, Scott, E-mail: Simpson80@gmail.com

    2014-10-15

    Highlights: • The most common cause of widespread ground-glass opacities is hydrostatic pulmonary edema. • Associated findings such as air-trapping and centrilobular nodules are highly specific for hypersensitivity pneumonitis. • The clinical setting (outpatient versus inpatient) will alter the order of the differential diagnosis. - Abstract: Purpose: The purpose of our study was to determine the relative frequencies of causes of widespread ground-glass opacity (GGO) in an unselected, consecutive patient population and to identify any associated imaging findings that can narrow or reorganize the differential. Materials and methods: The study was approved by the center's IRB and is HIPPA compliant. Cases with widespread GGO in the radiology report were identified by searching the Radiology Information System. Medical records and CT scan examinations were reviewed for the causes of widespread GGO. Associations between a less dominant imaging finding and a particular diagnosis were analyzed with the chi square test. Our study group consisted of 234 examinations with 124 women and 110 men and a mean age of 53.7 years. Results: A cause was established in 204 (87.2%) cases. Hydrostatic pulmonary edema was most common with 131 cases (56%). Interstitial lung diseases (ILD) were the next most common, most often hypersensitivity pneumonitis (HP) (n = 12, 5%) and connective tissue disease related ILD (n = 7, 3%). Infection accounted for 5% (12 cases). A few miscellaneous diseases accounted for 5 cases (2.1%). The combination of septal thickening and pleural effusions had a specificity of 0.91 for hydrostatic pulmonary edema (P < .001) while centrilobular nodules and air trapping had a specificity of 1.0 for HP. In 24 (10.2%) patients, increased opacification from expiration was incorrectly interpreted as representing widespread ground glass opacity. The relative frequency of disease dramatically changed according to the setting. In the inpatient setting, diffuse

  7. Frequency characterization of thin soft magnetic material layers used in spiral inductors

    International Nuclear Information System (INIS)

    Kriga, Adoum; Allassem, Désiré; Soultan, Malloum; Chatelon, Jean-Pierre; Siblini, Ali; Allard, Bruno; Rousseau, Jean Jacques

    2012-01-01

    The paper details the characterization of thin magnetic materials layers, particularly soft materials, with respect to their behaviour in frequency (from 10 MHz to 1 GHz). The proposed method is suitable for any soft but insulating magnetic material; Yttrium Iron Garnet (YIG) is used as an example. The principle is based on a comparison between simulations for different values of the permeability and measurement values versus frequency of planar inductor structures; an experimental validation is proposed as well. Thin magnetic material is first deposited on an alumina substrate using RF sputtering technique; a planar spiral winding of copper is then deposited on the magnetic material by the same technique. The effective permeability versus frequency is obtained by comparing two samples of spiral windings with and without magnetic material. Network analyser measurements on samples of various geometrical dimensions and of different thicknesses are necessary to determine the effective magnetic permeability; we have obtained a relative effective permeability of about 30 for seven turns spiral inductor of a 17 μm YIG film. - Highlights: ► A simple and original method is presented for the characterization of soft magnetic layer. ► This is a non-destructive method based on standard equipment. ► The principle is based on a comparison between simulations and measurement. ► An experimental validation is proposed as well.

  8. High-frequency response and the possibilities of frequency-tunable narrow-band terahertz amplification in resonant tunneling nanostructures

    International Nuclear Information System (INIS)

    Kapaev, V. V.; Kopaev, Yu. V.; Savinov, S. A.; Murzin, V. N.

    2013-01-01

    The characteristics of the high-frequency response of single- and double-well resonant tunneling structures in a dc electric field are investigated on the basis of the numerical solution of a time-dependent Schrödinger equation with open boundary conditions. The frequency dependence of the real part of high frequency conductivity (high-frequency response) in In 0.53 Ga 0.47 As/AlAs/InP structures is analyzed in detail for various values of the dc voltage V dc in the negative differential resistance (NDR) region. It is shown that double-well three-barrier structures are promising for the design of terahertz-band oscillators. The presence of two resonant states with close energies in such structures leads to a resonant (in frequency) response whose frequency is determined by the energy difference between these levels and can be controlled by varying the parameters of the structure. It is shown that, in principle, such structures admit narrow-band amplification, tuning of the amplification frequency, and a fine control of the amplification (oscillation) frequency in a wide range of terahertz frequencies by varying a dc electric voltage applied to the structure. Starting from a certain width of the central intermediate barrier in double-well structures, one can observe a collapse of resonances, where the structure behaves like a single-well system. This phenomenon imposes a lower limit on the oscillation frequency in three-barrier resonant tunneling structures.

  9. Time and frequency applications.

    Science.gov (United States)

    Hellwig, H

    1993-01-01

    An overview is given of the capabilities of atomic clocks and quartz crystal oscillators in terms of available precision of time and frequency signals. The generation, comparison, and dissemination of time and frequency is then discussed. The principal focus is to survey uses of time and frequency in navigation, communication, and science. The examples given include the Global Positioning System, a satellite-based global navigation system, and general and dedicated communication networks, as well as experiments in general relativity and radioastronomy. The number of atomic clocks and crystal oscillators that are in actual use worldwide is estimated.

  10. ICU director data: using data to assess value, inform local change, and relate to the external world.

    Science.gov (United States)

    Murphy, David J; Ogbu, Ogbonna C; Coopersmith, Craig M

    2015-04-01

    Improving value within critical care remains a priority because it represents a significant portion of health-care spending, faces high rates of adverse events, and inconsistently delivers evidence-based practices. ICU directors are increasingly required to understand all aspects of the value provided by their units to inform local improvement efforts and relate effectively to external parties. A clear understanding of the overall process of measuring quality and value as well as the strengths, limitations, and potential application of individual metrics is critical to supporting this charge. In this review, we provide a conceptual framework for understanding value metrics, describe an approach to developing a value measurement program, and summarize common metrics to characterize ICU value. We first summarize how ICU value can be represented as a function of outcomes and costs. We expand this equation and relate it to both the classic structure-process-outcome framework for quality assessment and the Institute of Medicine's six aims of health care. We then describe how ICU leaders can develop their own value measurement process by identifying target areas, selecting appropriate measures, acquiring the necessary data, analyzing the data, and disseminating the findings. Within this measurement process, we summarize common metrics that can be used to characterize ICU value. As health care, in general, and critical care, in particular, changes and data become more available, it is increasingly important for ICU leaders to understand how to effectively acquire, evaluate, and apply data to improve the value of care provided to patients.

  11. Eosinophilic Esophagitis in Children from Western Saudi Arabia: Relative Frequency, Clinical, Pathological, Endoscopic, and Immunological Study

    Directory of Open Access Journals (Sweden)

    Omar I. Saadah

    2012-01-01

    Full Text Available Background and Purpose. Eosinophilic esophagitis (EE is an evolving allergic disease with an accelerated incidence. The purpose of this study was to delineate the relative frequency and clinicopathological characteristics of EE in children from western Saudi Arabia. Methods. Children with EE were studied retrospectively between October 2002 and December 2011 at King Abdulaziz University Hospital and International Medical Center. Results. The relative frequency of EE was 0.85% of 2127 upper gastrointestinal endoscopies performed during the study period. Eighteen patients were identified with EE. The median age was 8.6 years (range, 1.5–18 years. Thirteen (72.2% were males. Dysphagia and vomiting were the most common symptoms. Ten (55.6% children had history of atopy. Testing for food allergy by skin prick test was positive in 11 (61.1%. The most common endoscopic abnormalities were mucosal longitudinal furrow and loss of vascular pattern followed by patchy specks and strictures. The histopathological findings included increased intraepithelial eosinophils, eosinophilic degranulation, lamina propria fibrosis, and eosinophilic microabscesses. Treatment was initiated by swallowed topical corticosteroids in 12 (66.7% and oral prednisolone in 6 (33% patients, followed by low dose of topical corticosteroids and dietary elimination. Conclusions. Eosinophilic esophagitis is an uncommon but evolving problem. A high index of suspicion is required for early identifications and intervention to avoid possible complications.

  12. Climate Informed Low Flow Frequency Analysis Using Nonstationary Modeling

    Science.gov (United States)

    Liu, D.; Guo, S.; Lian, Y.

    2014-12-01

    Stationarity is often assumed for frequency analysis of low flows in water resources management and planning. However, many studies have shown that flow characteristics, particularly the frequency spectrum of extreme hydrologic events,were modified by climate change and human activities and the conventional frequency analysis without considering the non-stationary characteristics may lead to costly design. The analysis presented in this paper was based on the more than 100 years of daily flow data from the Yichang gaging station 44 kilometers downstream of the Three Gorges Dam. The Mann-Kendall trend test under the scaling hypothesis showed that the annual low flows had significant monotonic trend, whereas an abrupt change point was identified in 1936 by the Pettitt test. The climate informed low flow frequency analysis and the divided and combined method are employed to account for the impacts from related climate variables and the nonstationarities in annual low flows. Without prior knowledge of the probability density function for the gaging station, six distribution functions including the Generalized Extreme Values (GEV), Pearson Type III, Gumbel, Gamma, Lognormal, and Weibull distributions have been tested to find the best fit, in which the local likelihood method is used to estimate the parameters. Analyses show that GEV had the best fit for the observed low flows. This study has also shown that the climate informed low flow frequency analysis is able to exploit the link between climate indices and low flows, which would account for the dynamic feature for reservoir management and provide more accurate and reliable designs for infrastructure and water supply.

  13. Design and evaluation of a flow-to-frequency converter circuit with thermal feedback

    International Nuclear Information System (INIS)

    Pawlowski, Eligiusz

    2017-01-01

    A novel thermal flow sensor with a frequency output is presented. The sensor provides a pulse-train output whose frequency is related to the fluid flow rate around a self-heating thermistor. The integrating properties of the temperature sensor have been used, which allowed for realization of the pulse frequency modulator with a thermal feedback loop, stabilizing the temperature of the sensor placed in the flowing medium. The system assures a balance of the amount of heat supplied in the impulses to the sensor and the heat given up by the sensor in a continuous way to the flowing medium. Therefore the frequency of output pulse-train is proportional to the medium flow velocity around the sensor. The special feature of the presented solution is the total integration of the thermal sensor with the measurement signal conditioning system. i.e. the sensor and conditioning system are not separate elements of the measurement circuit, but constitute a whole in the form of a thermal heat-balance mode flow-to-frequency converter. The frequency signal from the converter may be directly connected to the microprocessor digital input, which with use of the standard built-in counters may convert the frequency into a numerical value of high precision. The sensor has been experimentally characterized as a function of the average flow velocity of air at room temperature. (paper)

  14. 40 CFR 600.208-12 - Calculation of FTP-based and HFET-based fuel economy and carbon-related exhaust emission values...

    Science.gov (United States)

    2010-07-01

    ...-based fuel economy and carbon-related exhaust emission values for a model type. 600.208-12 Section 600... ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Regulations for 1977 and Later...-based and HFET-based fuel economy and carbon-related exhaust emission values for a model type. (a) Fuel...

  15. Frequency Chirping during a Fishbone Burst

    Energy Technology Data Exchange (ETDEWEB)

    Marchenko, V.; Reznik, S., E-mail: march@kinr.kiev.ua [Institute for Nuclear Research, Kyiv (Ukraine)

    2012-09-15

    Full text: It is shown that gradual (more than a factor of two, in some cases - down to zero in the lab frame) reduction of the mode frequency (the so called frequency chirping) can be attributed to the reactive torque exerted on the plasma during the fishbone instability burst, which slows down the plasma rotation inside the q = 1 surface and reduces the mode frequency in the lab frame, while frequency in the plasma frame remains constant. This torque arises due to imbalance between the power transfered to the mode by energeric ions and the power of the mode dissipation by thermal species. Estimates show that the peak value of this torque exceeds the neutral beam torque in modern tokamaks and in ITER. The line-broadened quasilinear burst model, properly adapted for the fishbone case, is capable of reproducing the key features of the bursting mode. (author)

  16. Value concepts and value based collaboration in building projects

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2005-01-01

    Value has in recent years become a popular term in management theory and practice in general as well as in economic theory and architectural management. This paper attempts to clarify the various uses and meanings of concepts of value/values. Six different value concepts are identified. The ori......-gin and use of value concepts in classic and modern economic theory and in management theory is outlined. The question of objectivity and subjectivity is discussed in relation to economic value and customer value. Value creation is put in relation to development in products and processes and a number...... of design strategies are identified. The concept and methods of value based management and collaboration is discussed in this context. The paper is mainly theoretical and based on work during a MBA study in 2002-04 as well as many years of experience as building client and facilities manager....

  17. Recreation Value of Water to Wetlands in the San Joaquin Valley: Linked Multinomial Logit and Count Data Trip Frequency Models

    Science.gov (United States)

    Creel, Michael; Loomis, John

    1992-10-01

    The recreational benefits from providing increased quantities of water to wildlife and fisheries habitats is estimated using linked multinomial logit site selection models and count data trip frequency models. The study encompasses waterfowl hunting, fishing and wildlife viewing at 14 recreational resources in the San Joaquin Valley, including the National Wildlife Refuges, the State Wildlife Management Areas, and six river destinations. The economic benefits of increasing water supplies to wildlife refuges were also examined by using the estimated models to predict changing patterns of site selection and overall participation due to increases in water allocations. Estimates of the dollar value per acre foot of water are calculated for increases in water to refuges. The resulting model is a flexible and useful tool for estimating the economic benefits of alternative water allocation policies for wildlife habitat and rivers.

  18. The applicability of Relative Floristic Resemblance to evaluate the conservation value of protected areas.

    NARCIS (Netherlands)

    Wieringa, J.J.; Sosef, M.S.M.

    2011-01-01

    s – It is important to know the contribution of a protected area to global conservation. A new method called ‘Relative Floristic Resemblance’ that uses databased and georeferenced herbarium specimens, is introduced. Its usefulness and applicability to assess the conservation value of protected areas

  19. Values in a Science of Social Work: Values-Informed Research and Research-Informed Values

    Science.gov (United States)

    Longhofer, Jeffrey; Floersch, Jerry

    2014-01-01

    While social work must be evaluative in relation to its diverse areas of practice and research (i.e., values-informed research), the purpose of this article is to propose that values are within the scope of research and therefore research on practice should make values a legitimate object of investigation (i.e., research-informed values). In this…

  20. Accurate frequency measurements on gyrotrons using a ''gyro-radiometer''

    International Nuclear Information System (INIS)

    Rebuffi, L.

    1986-08-01

    Using an heterodyne system, called ''Gyro-radiometer'', accurated frequency measurements have been carried out on VARIAN 60 GHz gyrotrons. Changing the principal tuning parameters of a gyrotron, we have detected frequency variations up to 100 MHz, ∼ 40 MHz frequency jumps and smaller jumps (∼ 10 MHz) when mismatches in the transmission line were present. FWHM bandwidth of 300 KHz, parasitic frequencies and frequency drift during 100 msec pulses have also been observed. An efficient method to find a stable-, high power-, long pulse-working point of a gyrotron loaded by a transmission line, has been derived. In general, for any power value it is possible to find stable working conditions tuning the principal parameters of the tube in correspondance of a maximum of the emitted frequency

  1. The frequency range of TMJ sounds.

    Science.gov (United States)

    Widmalm, S E; Williams, W J; Djurdjanovic, D; McKay, D C

    2003-04-01

    There are conflicting opinions about the frequency range of temporomandibular joint (TMJ) sounds. Some authors claim that the upper limit is about 650 Hz. The aim was to test the hypothesis that TMJ sounds may contain frequencies well above 650 Hz but that significant amounts of their energy are lost if the vibrations are recorded using contact sensors and/or travel far through the head tissues. Time-frequency distributions of 172 TMJ clickings (three subjects) were compared between recordings with one microphone in the ear canal and a skin contact transducer above the clicking joint and between recordings from two microphones, one in each ear canal. The energy peaks of the clickings recorded with a microphone in the ear canal on the clicking side were often well above 650 Hz and always in a significantly higher area (range 117-1922 Hz, P 375 Hz) or in microphone recordings from the opposite ear canal (range 141-703 Hz). Future studies are required to establish normative frequency range values of TMJ sounds but need methods also capable of recording the high frequency vibrations.

  2. Design of etch holes to compensate spring width loss for reliable resonant frequencies

    International Nuclear Information System (INIS)

    Jang, Yun-Ho; Kim, Jong-Wan; Kim, Yong-Kweon; Kim, Jung-Mu

    2012-01-01

    A pattern width loss during the fabrication of lateral silicon resonators degrades resonant frequency reliability since such a width loss causes the significant deviation of spring stiffness. Here we present a design guide for etch holes to obtain reliable resonant frequencies by controlling etch holes geometries. The new function of an etch hole is to generate the comparable amount of the width loss between springs and etch holes, in turn to minimize the effect of the spring width loss on resonant frequency shift and deviation. An analytic expression reveals that a compensation factor (CF), defined by the circumference (C u ) of a unit etch hole divided by its silicon area (A u ), is a key parameter for reliable frequencies. The protrusive etch holes were proposed and compared with square etch holes to demonstrate the frequency reliability according to CF values and etch hole shapes. The normalized resonant frequency shift and deviation of the protrusive etch hole (−13.0% ± 6.9%) were significantly improved compared to those of a square etch hole with a small CF value (−42.8% ± 14.8%). The proposed design guide based on the CF value and protrusive shapes can be used to achieve reliable resonant frequencies for high performance silicon resonators. (technical note)

  3. A common microstructure in behavioral hearing thresholds and stimulus-frequency otoacoustic emissions.

    Science.gov (United States)

    Dewey, James B; Dhar, Sumitrajit

    2017-11-01

    Behavioral hearing thresholds and otoacoustic emission (OAE) spectra often exhibit quasiperiodic fluctuations with frequency. For behavioral and OAE responses to single tones-the latter referred to as stimulus-frequency otoacoustic emissions (SFOAEs)-this microstructure has been attributed to intracochlear reflections of SFOAE energy between its region of generation and the middle ear boundary. However, the relationship between behavioral and SFOAE microstructures, as well as their presumed dependence on the properties of the SFOAE-generation mechanism, have yet to be adequately examined. To address this, behavioral thresholds and SFOAEs evoked by near-threshold tones were compared in 12 normal-hearing female subjects. The microstructures observed in thresholds and both SFOAE amplitudes and delays were found to be strikingly similar. SFOAE phase accumulated an integer number of cycles between the frequencies of microstructure maxima, consistent with a dependence of microstructure periodicity on SFOAE propagation delays. Additionally, microstructure depth was correlated with SFOAE magnitude in a manner resembling that predicted by the intracochlear reflection framework, after assuming reasonable values of parameters related to middle ear transmission. Further exploration of this framework may yield more precise estimates of such parameters and provide insight into their frequency dependence.

  4. Frequency chirping during a fishbone burst

    International Nuclear Information System (INIS)

    Marchenko, V.S.; Reznik, S.N.

    2011-01-01

    It is shown that frequency chirping during fishbone activity can be attributed to the reactive torque exerted on the plasma during the instability burst, which slows down plasma rotation inside the q = 1 surface and reduces the mode frequency in the lab frame. Estimates show that the peak value of this torque can exceed the neutral beam torque in modern tokamaks. The simple line-broadened quasilinear burst model (Berk et al 1995 Nucl. Fusion 35 1661), properly adapted for the fishbone case, is capable of reproducing the key features of the bursting mode. (letter)

  5. Demodulation Radio Frequency Interference Effects in Operational Amplifier Circuits

    Science.gov (United States)

    Sutu, Yue-Hong

    within 6 and 7 dB respectively for RF frequencies 0.1 to 400 MHz except near the resonant frequencies for the LF355 circuit. (4) The NCAP simulations suggest that the resonances of the LF355 unity gain buffer circuit are related to small parasitic capacitance values of the order of 1 to 5 pF. (5) The NCAP sensitivity analysis indicates that variations in a second-order transfer function are sensitive to some macromodel parameters.

  6. Brain alterations in low-frequency fluctuations across multiple bands in obsessive compulsive disorder.

    Science.gov (United States)

    Giménez, Mònica; Guinea-Izquierdo, Andrés; Villalta-Gil, Victoria; Martínez-Zalacaín, Ignacio; Segalàs, Cinto; Subirà, Marta; Real, Eva; Pujol, Jesús; Harrison, Ben J; Haro, Josep Maria; Sato, Joao R; Hoexter, Marcelo Q; Cardoner, Narcís; Alonso, Pino; Menchón, José Manuel; Soriano-Mas, Carles

    2017-12-01

    The extent of functional abnormalities in frontal-subcortical circuits in obsessive-compulsive disorder (OCD) is still unclear. Although neuroimaging studies, in general, and resting-state functional Magnetic Resonance Imaging (rs-fMRI), in particular, have provided relevant information regarding such alterations, rs-fMRI studies have been typically limited to the analysis of between-region functional connectivity alterations at low-frequency signal fluctuations (i.e., <0.08 Hz). Conversely, the local attributes of Blood Oxygen Level Dependent (BOLD) signal across different frequency bands have been seldom studied, although they may provide valuable information. Here, we evaluated local alterations in low-frequency fluctuations across different oscillation bands in OCD. Sixty-five OCD patients and 50 healthy controls underwent an rs-fMRI assessment. Alterations in the fractional amplitude of low-frequency fluctuations (fALFF) were evaluated, voxel-wise, across four different bands (from 0.01 Hz to 0.25 Hz). OCD patients showed decreased fALFF values in medial orbitofrontal regions and increased fALFF values in the dorsal-medial prefrontal cortex (DMPFC) at frequency bands <0.08 Hz. This pattern was reversed at higher frequencies, where increased fALFF values also appeared in medial temporal lobe structures and medial thalamus. Clinical variables (i.e., symptom-specific severities) were associated with fALFF values across the different frequency bands. Our findings provide novel evidence about the nature and regional distribution of functional alterations in OCD, which should contribute to refine neurobiological models of the disorder. We suggest that the evaluation of the local attributes of BOLD signal across different frequency bands may be a sensitive approach to further characterize brain functional alterations in psychiatric disorders.

  7. Infrasound and low frequency noise from wind turbines: exposure and health effects

    Energy Technology Data Exchange (ETDEWEB)

    Bolin, Karl [Marcus Wallenberg Laboratory, Department of Aeronautical and Vehicle Engineering, Kungliga Tekniska Hoegskolan (Sweden); Bluhm, Goesta; Nilsson, Mats E [Institute of Environmental Medicine, Karolinska Institutet (Sweden); Eriksson, Gabriella, E-mail: kbolin@kth.se [Swedish National Road and Transport Research Institute and Linkoeping University (Sweden)

    2011-07-15

    Wind turbines emit low frequency noise (LFN) and large turbines generally generate more LFN than small turbines. The dominant source of LFN is the interaction between incoming turbulence and the blades. Measurements suggest that indoor levels of LFN in dwellings typically are within recommended guideline values, provided that the outdoor level does not exceed corresponding guidelines for facade exposure. Three cross-sectional questionnaire studies show that annoyance from wind turbine noise is related to the immission level, but several explanations other than low frequency noise are probable. A statistically significant association between noise levels and self-reported sleep disturbance was found in two of the three studies. It has been suggested that LFN from wind turbines causes other, and more serious, health problems, but empirical support for these claims is lacking.

  8. Optimal supplementary frequency controller design using the wind farm frequency model and controller parameters stability region.

    Science.gov (United States)

    Toulabi, Mohammadreza; Bahrami, Shahab; Ranjbar, Ali Mohammad

    2018-03-01

    In most of the existing studies, the frequency response in the variable speed wind turbines (VSWTs) is simply realized by changing the torque set-point via appropriate inputs such as frequency deviations signal. However, effective dynamics and systematic process design have not been comprehensively discussed yet. Accordingly, this paper proposes a proportional-derivative frequency controller and investigates its performance in a wind farm consisting of several VSWTs. A band-pass filter is deployed before the proposed controller to avoid responding to either steady state frequency deviations or high rate of change of frequency. To design the controller, the frequency model of the wind farm is first characterized. The proposed controller is then designed based on the obtained open loop system. The stability region associated with the controller parameters is analytically determined by decomposing the closed-loop system's characteristic polynomial into the odd and even parts. The performance of the proposed controller is evaluated through extensive simulations in MATLAB/Simulink environment in a power system comprising a high penetration of VSWTs equipped with the proposed controller. Finally, based on the obtained feasible area and appropriate objective function, the optimal values associated with the controller parameters are determined using the genetic algorithm (GA). Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Method of detecting system function by measuring frequency response

    Science.gov (United States)

    Morrison, John L [Butte, MT; Morrison, William H [Manchester, CT; Christophersen, Jon P [Idaho Falls, ID

    2012-04-03

    Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

  10. Teaching Philosophy Game - A Way to Clarify Values, Attitudes, and Preferences Related to Teaching

    DEFF Research Database (Denmark)

    Christiansen, Birgitte Lund; Hansen, Claus Thorp; Jensen, Lars Bogø

    The authors propose a game that can be used to clarify faculty members’ values, attitudes,and preferences related to teaching and learning. The game is intended to establish a guided, yet unformal and amusing, framework for considering and discussing what staff members find important in their tas...

  11. Improved Load Frequency Control Using a Fast Acting Active Disturbance Rejection Controller

    Directory of Open Access Journals (Sweden)

    Md Mijanur Rahman

    2017-10-01

    Full Text Available System frequency may change from defined values while transmitting power from one area to another in an interconnected power system due to various reasons such as load changes and faults. This frequency change causes a frequency error in the system. However, the system frequency should always be maintained close to the nominal value even in the presence of model uncertainties and physical constraints. This paper proposes an Active Disturbance Rejection Controller (ADRC-based load frequency control (LFC of an interconnected power system. The controller incorporates effects of generator inertia and generator electrical proximity to the point of disturbances. The proposed controller reduces the magnitude error of the area control error (ACE of an interconnected power system compared to the standard controller. The simulation results verify the effectiveness of proposed ADRC in the application of LFC of an interconnected power system.

  12. Investigation of the Relationship Between Electrical Stimulation Frequency and Muscle Frequency Response Under Submaximal Contractions.

    Science.gov (United States)

    Papcke, Caluê; Krueger, Eddy; Olandoski, Marcia; Nogueira-Neto, Guilherme Nunes; Nohama, Percy; Scheeren, Eduardo Mendonça

    2018-03-25

    Neuromuscular electrical stimulation (NMES) is a common tool that is used in clinical and laboratory experiments and can be combined with mechanomyography (MMG) for biofeedback in neuroprostheses. However, it is not clear if the electrical current applied to neuromuscular tissues influences the MMG signal in submaximal contractions. The objective of this study is to investigate whether the electrical stimulation frequency influences the mechanomyographic frequency response of the rectus femoris muscle during submaximal contractions. Thirteen male participants performed three maximal voluntary isometric contractions (MVIC) recorded in isometric conditions to determine the maximal force of knee extensors. This was followed by the application of nine modulated NMES frequencies (20, 25, 30, 35, 40, 45, 50, 75, and 100 Hz) to evoke 5% MVIC. Muscle behavior was monitored by the analysis of MMG signals, which were decomposed into frequency bands by using a Cauchy wavelet transform. For each applied electrical stimulus frequency, the mean MMG spectral/frequency response was estimated for each axis (X, Y, and Z axes) of the MMG sensor with the values of the frequency bands used as weights (weighted mean). Only with respect to the Z (perpendicular) axis of the MMG signal, the stimulus frequency of 20 Hz did not exhibit any difference with the weighted mean (P = 0.666). For the frequencies of 20 and 25 Hz, the MMG signal displayed the bands between 12 and 16 Hz in the three axes (P frequencies from 30 to 100 Hz, the muscle presented a higher concentration of the MMG signal between the 22 and 29 Hz bands for the X and Z axes, and between 16 and 34 Hz bands for the Y axis (P frequency, because their frequency contents tend to mainly remain between the 20- and 25-Hz bands. Hence, NMES does not interfere with the use of MMG in neuroprosthesis. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  13. High-efficiency frequency doubling of continuous-wave laser light.

    Science.gov (United States)

    Ast, Stefan; Nia, Ramon Moghadas; Schönbeck, Axel; Lastzka, Nico; Steinlechner, Jessica; Eberle, Tobias; Mehmet, Moritz; Steinlechner, Sebastian; Schnabel, Roman

    2011-09-01

    We report on the observation of high-efficiency frequency doubling of 1550 nm continuous-wave laser light in a nonlinear cavity containing a periodically poled potassium titanyl phosphate crystal (PPKTP). The fundamental field had a power of 1.10 W and was converted into 1.05 W at 775 nm, yielding a total external conversion efficiency of 95±1%. The latter value is based on the measured depletion of the fundamental field being consistent with the absolute values derived from numerical simulations. According to our model, the conversion efficiency achieved was limited by the nonperfect mode matching into the nonlinear cavity and by the nonperfect impedance matching for the maximum input power available. Our result shows that cavity-assisted frequency conversion based on PPKTP is well suited for low-decoherence frequency conversion of quantum states of light.

  14. Flood frequency analysis of historical flood data under stationary and non-stationary modelling

    Science.gov (United States)

    Machado, M. J.; Botero, B. A.; López, J.; Francés, F.; Díez-Herrero, A.; Benito, G.

    2015-06-01

    Historical records are an important source of information on extreme and rare floods and fundamental to establish a reliable flood return frequency. The use of long historical records for flood frequency analysis brings in the question of flood stationarity, since climatic and land-use conditions can affect the relevance of past flooding as a predictor of future flooding. In this paper, a detailed 400 yr flood record from the Tagus River in Aranjuez (central Spain) was analysed under stationary and non-stationary flood frequency approaches, to assess their contribution within hazard studies. Historical flood records in Aranjuez were obtained from documents (Proceedings of the City Council, diaries, chronicles, memoirs, etc.), epigraphic marks, and indirect historical sources and reports. The water levels associated with different floods (derived from descriptions or epigraphic marks) were computed into discharge values using a one-dimensional hydraulic model. Secular variations in flood magnitude and frequency, found to respond to climate and environmental drivers, showed a good correlation between high values of historical flood discharges and a negative mode of the North Atlantic Oscillation (NAO) index. Over the systematic gauge record (1913-2008), an abrupt change on flood magnitude was produced in 1957 due to constructions of three major reservoirs in the Tagus headwaters (Bolarque, Entrepeñas and Buendia) controlling 80% of the watershed surface draining to Aranjuez. Two different models were used for the flood frequency analysis: (a) a stationary model estimating statistical distributions incorporating imprecise and categorical data based on maximum likelihood estimators, and (b) a time-varying model based on "generalized additive models for location, scale and shape" (GAMLSS) modelling, which incorporates external covariates related to climate variability (NAO index) and catchment hydrology factors (in this paper a reservoir index; RI). Flood frequency

  15. [Anemic syndrome frequency in complicated obstetrical patients].

    Science.gov (United States)

    Martínez, Maria Guadalupe Veloz; Erasto, Luis Cruz; Maxines, Claudia García; Rodríguez, María Antonia Basavilvazo; Valencia, Marcelino Hernández

    2008-09-01

    The prevalence of anemia varies from country to country and there is not a trustworthy record. To determine the frequency of anemia in obstetric patients and the association among healthy pregnancy and aggregate complications. Was carried out as transversal, observational and comparative study. Obstetrical patients entered and responded in the period of a year, were formed a group with normal pregnancy and another with complicated pregnancy, with a total sample of 194 patients. In the statistical analysis was employed Student t test for independent groups, with value if p anemia was found in 22.4%. Hematological stage from group with normal pregnancy was mild anemia in 16.9% and anemia moderated in 4.1% of the cases. The anemia degrees in the group with associated illness and pregnancy were mild anemia in 19.2% and moderated anemia in 4.2%. Not any case was found with severe anemia. The statistical analysis showed difference significant among both groups p preeclampsia severe (22.6%), type 2 diabetes (13.9%), gestational diabetes (12.2%) and the remainder with other complications that include to the hypertiroidism, rheumatoid arthritis, lupus, asthma and vein deep thrombosis. Frequency of anemia in this study was greater upon informing in the international literature. The obstetrical complication more frequently relates to diverse anemia degrees were the hypertensive stage during pregnancy. The anemia is presented with greater frequency in pregnancy patients with others associated illness.

  16. Task-Related Modulations of BOLD Low-Frequency Fluctuations within the Default Mode Network

    Science.gov (United States)

    Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Assan, Ibrahim Eid; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico

    2017-01-01

    Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task. PMID:28845420

  17. Task-Related Modulations of BOLD Low-Frequency Fluctuations within the Default Mode Network

    Directory of Open Access Journals (Sweden)

    Silvia Tommasin

    2017-07-01

    Full Text Available Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN, are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task.

  18. Trade-off Analysis of Virtual Inertia and Fast Primary Frequency Control During Frequency Transients in a Converter Dominated Network

    DEFF Research Database (Denmark)

    Rezkalla, Michel M.N.; Marinelli, Mattia; Pertl, Michael

    2016-01-01

    Traditionally the electricity generation is based on rotating synchronous machines which provide inertia to the power system.The increasing share of converter connected energy sources reduces the available rotational inertia in the power system leading to faster frequency dynamics, which may cause...... more critical frequency excursions. Both, virtual inertia and fast primary control could serve as a solution to improvefrequency stability, however, their respective impacts on the system have different consequences, so that the trade-off is not straightforward. This study presents a comparative...... analysis of virtual inertiaand a fast primary control algorithms with respect to rate of change of frequency (ROCOF), frequency nadir and steady state value considering the effect of the dead time which is carried out by a sensitivity analysis. The investigation shows that the virtual inertia controller...

  19. Radio-frequency shot-noise measurement in a magnetic tunnel junction with a MgO barrier

    International Nuclear Information System (INIS)

    Rehman, Mushtaq; Park, Junghwan; Song, Woon; Chong, Yonuk; Lee, Yeonsub; Min, Byoungchul; Shin, Kyungho; Ryu, Sangwan; Khim, Zheong

    2010-01-01

    We measured the noise power of a magnetic tunnel junction in the frequency range of 710 ∼ 1200 MHz. A low-noise cryogenic HEMT amplifier was used to measure the small noise signal at a high frequency with wide bandwidth. The MgO-barrier tunnel junction showed large tunnel magnetoresistance ratio of 215% at low temperature, which indicates electronic transport through the tunnel barrier without any significant spin-flip scattering. In the bias-dependent noise measurement, however, the zero-bias shot noise was enhanced compared to the value expected from a perfect tunnel barrier or the value observed from a good Al-AlO x -Al tunnel junction. We assume that this enhanced noise comes from inelastic tunneling processes through the barrier, which may be related to the observed zero-bias anomaly in the differential resistance of the tunnel junctions. We present a simple phenomenological model for how the inelastic scattering process can enhance the zero-bias noise in a tunnel junction.

  20. Laser frequency modulation with electron plasma

    Science.gov (United States)

    Burgess, T. J.; Latorre, V. R.

    1972-01-01

    When laser beam passes through electron plasma its frequency shifts by amount proportional to plasma density. This density varies with modulating signal resulting in corresponding modulation of laser beam frequency. Necessary apparatus is relatively inexpensive since crystals are not required.

  1. Competition between Final-State and Pairing-Gap Effects in the Radio-Frequency Spectra of Ultracold Fermi Atoms

    International Nuclear Information System (INIS)

    Perali, A.; Pieri, P.; Strinati, G. C.

    2008-01-01

    The radio-frequency spectra of ultracold Fermi atoms are calculated by including final-state interactions affecting the excited level of the transition and compared with the experimental data. A competition is revealed between pairing-gap effects which tend to push the oscillator strength toward high frequencies away from threshold and final-state effects which tend instead to pull the oscillator strength toward threshold. As a result of this competition, the position of the peak of the spectra cannot be simply related to the value of the pairing gap, whose extraction thus requires support from theoretical calculations

  2. High frequency conductivity in carbon nanotubes

    Directory of Open Access Journals (Sweden)

    S. S. Abukari

    2012-12-01

    Full Text Available We report on theoretical analysis of high frequency conductivity in carbon nanotubes. Using the kinetic equation with constant relaxation time, an analytical expression for the complex conductivity is obtained. The real part of the complex conductivity is initially negative at zero frequency and become more negative with increasing frequency, until it reaches a resonance minimum at ω ∼ ωB for metallic zigzag CNs and ω < ωB for armchair CNs. This resonance enhancement is indicative for terahertz gain without the formation of current instabilities induced by negative dc conductivity. We noted that due to the high density of states of conduction electrons in metallic zigzag carbon nanotubes and the specific dispersion law inherent in hexagonal crystalline structure result in a uniquely high frequency conductivity than the corresponding values for metallic armchair carbon nanotubes. We suggest that this phenomenon can be used to suppress current instabilities that are normally associated with a negative dc differential conductivity.

  3. Time-frequency analysis and harmonic Gaussian functions

    International Nuclear Information System (INIS)

    Ranaivoson, R.T.R; Raoelina Andriambololona; Hanitriarivo, R.

    2013-01-01

    A method for time-frequency analysis is given. The approach utilizes properties of Gaussian distribution, properties of Hermite polynomials and Fourier analysis. We begin by the definitions of a set of functions called Harmonic Gaussian Functions. Then these functions are used to define a set of transformations, noted Τ n , which associate to a function ψ, of the time variable t, a set of functions Ψ n which depend on time, frequency and frequency (or time) standard deviation. Some properties of the transformations Τ n and the functions Ψ n are given. It is proved in particular that the square of the modulus of each function Ψ n can be interpreted as a representation of the energy distribution of the signal, represented by the function ψ, in the time-frequency plane for a given value of the frequency (or time) standard deviation. It is also shown that the function ψ can be recovered from the functions Ψ n .

  4. Determination of the frequency of polymorphisms in genes related to the genome stability maintenance of the population residing at Monte Alegre, PA (Brazil) municipality

    International Nuclear Information System (INIS)

    Hozumi, Cristiny Gomes

    2010-01-01

    The human exposure to ionizing radiation coming from natural sources is an inherent feature of human life on earth, for man and all living things have always been exposed to these sources. Ionizing radiation is a known genotoxic agent which can affect the genomic stability and genes related to DNA repair may play a role when they have committed certain polymorphism. This study aimed to analyze the frequency of polymorphisms (SNPs) in genes of DNA repair and cell cycle control: hOGG1 (Ser326Cys), XRCC3 (Thr241 Met) and p53 (Arg72Pro) in saliva samples from a population located Monte Alegre, state of Para were collected in August 2008 and 40 samples of men and 46 samples of women, adding a total of 86 samples. By RFLP was determined the frequency of homozygous genotypes and / or heterozygous for polymorphic genes. The I)OGG1 gene was 5% of the allele 326Cys, XRCC3 gene found about 21 % of the allele 241 Met and p53 gene showed 40.8% of the 72Pro allele. And the genotype frequencies of individuals for the three genes were 91.04%, 88.06% and 59.7% for homozygous wild genotype, 5.97%, 11.94% and 22.39% for heterozygote genotype and 2,99%, zero and 17:91% for homozygous polymorphic hOGG1 genes respectively, XRCC3, p53. These values are similar to those found in previous studies. The influence of these polymorphisms, which are involved in DNA repair and consequent genotoxicity induced by radiation depends on dose and exposure factors such as smoking, which is statistically a factor in public health surveillance in the region. This study gathered information and molecular epidemiology in Monte Alegre, that help to characterization of local population. (author)

  5. Influences of Fundamental Frequency, Formant Frequencies, Aperiodicity, and Spectrum Level on the Perception of Voice Gender

    Science.gov (United States)

    Skuk, Verena G.; Schweinberger, Stefan R.

    2014-01-01

    Purpose: To determine the relative importance of acoustic parameters (fundamental frequency [F0], formant frequencies [FFs], aperiodicity, and spectrum level [SL]) on voice gender perception, the authors used a novel parameter-morphing approach that, unlike spectral envelope shifting, allows the application of nonuniform scale factors to transform…

  6. Estimation of Existence Geothermal Manifestation Using Very Low Frequency (VLF) Method in the PagerkandangVulcanic, Dieng, Central Java

    Science.gov (United States)

    Wulandari, Asri; Asti Anggari, Ega; Dwiasih, Novi; Suyanto, Imam

    2018-03-01

    Very Low Frequency (VLF) measurement has been done at Pagerkandang Volcanic, Dieng Volcanic Complex (DVC) to examine the possible existence of conductive zones that related with geothermal manifestation. VLF – EM survey used tilt mode with T-VLF BRGM Iris Instrument operated with two frequencies, they are 22200 Hz from Japan (JJI) and 19800 Hz from Australia (NWC). There are five lines with distance between lines is 50 m, and distance between measure points is 20 m. The parameters measured from VLF method are tilt angle (%) and elliptisity (%). Data processed by tilt angle value with fraser and Karous – Hjelt filter used WinVLF program. Karous – Hjelt filter resulted current density contour to estimate lateral location from conductive and resistive zones. The conductive zone is interpreted as the area which have high current density value. This area located at eastern dan western of Pagerkandang Volcanic. The conductive zone related to geothermal manifestation as like as fumarol that appeared because presenced of normal fault. Whereas the resistive zone is interpreted as the area which have low current density value. This area spread almost in the middle of the Pagerkandang Volcanic. The resistive zone was caused by the high weathering in claystone.

  7. Frequency-Selective Attention in Auditory Scenes Recruits Frequency Representations Throughout Human Superior Temporal Cortex.

    Science.gov (United States)

    Riecke, Lars; Peters, Judith C; Valente, Giancarlo; Kemper, Valentin G; Formisano, Elia; Sorger, Bettina

    2017-05-01

    A sound of interest may be tracked amid other salient sounds by focusing attention on its characteristic features including its frequency. Functional magnetic resonance imaging findings have indicated that frequency representations in human primary auditory cortex (AC) contribute to this feat. However, attentional modulations were examined at relatively low spatial and spectral resolutions, and frequency-selective contributions outside the primary AC could not be established. To address these issues, we compared blood oxygenation level-dependent (BOLD) responses in the superior temporal cortex of human listeners while they identified single frequencies versus listened selectively for various frequencies within a multifrequency scene. Using best-frequency mapping, we observed that the detailed spatial layout of attention-induced BOLD response enhancements in primary AC follows the tonotopy of stimulus-driven frequency representations-analogous to the "spotlight" of attention enhancing visuospatial representations in retinotopic visual cortex. Moreover, using an algorithm trained to discriminate stimulus-driven frequency representations, we could successfully decode the focus of frequency-selective attention from listeners' BOLD response patterns in nonprimary AC. Our results indicate that the human brain facilitates selective listening to a frequency of interest in a scene by reinforcing the fine-grained activity pattern throughout the entire superior temporal cortex that would be evoked if that frequency was present alone. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Explicit solution for the natural frequency of structures with partial viscoelastic treatment

    OpenAIRE

    Høgsberg, Jan Becker

    2016-01-01

    The free vibration characteristics of structures with viscoelastic treatment are represented by the complex-valued natural frequencies. The assumed single mode representation associated with the low-frequency stiffness of the viscoelastic treatment is modified by a correction term representing the influence from residual vibration modes. The correction term is eliminated in terms of the corresponding natural frequency associated with the high-frequency stiffness of the viscoelastic treatment,...

  9. Secondary Frequency and Voltage Control of Islanded Microgrids via Distributed Averaging

    DEFF Research Database (Denmark)

    W. Simpson-Porco, John; Shafiee, Qobad; Dorfler, Florian

    2015-01-01

    actions. The frequency controller rapidly regulates the microgrid frequency to its nominal value while maintaining active power sharing among the distributed generators. Tuning of the voltage controller provides a simple and intuitive trade-off between the conflicting goals of voltage regulation...

  10. Geometric Least Square Models for Deriving [0,1]-Valued Interval Weights from Interval Fuzzy Preference Relations Based on Multiplicative Transitivity

    Directory of Open Access Journals (Sweden)

    Xuan Yang

    2015-01-01

    Full Text Available This paper presents a geometric least square framework for deriving [0,1]-valued interval weights from interval fuzzy preference relations. By analyzing the relationship among [0,1]-valued interval weights, multiplicatively consistent interval judgments, and planes, a geometric least square model is developed to derive a normalized [0,1]-valued interval weight vector from an interval fuzzy preference relation. Based on the difference ratio between two interval fuzzy preference relations, a geometric average difference ratio between one interval fuzzy preference relation and the others is defined and employed to determine the relative importance weights for individual interval fuzzy preference relations. A geometric least square based approach is further put forward for solving group decision making problems. An individual decision numerical example and a group decision making problem with the selection of enterprise resource planning software products are furnished to illustrate the effectiveness and applicability of the proposed models.

  11. Interval Continuous Plant Identification from Value Sets

    Directory of Open Access Journals (Sweden)

    R. Hernández

    2012-01-01

    Full Text Available This paper shows how to obtain the values of the numerator and denominator Kharitonov polynomials of an interval plant from its value set at a given frequency. Moreover, it is proven that given a value set, all the assigned polynomials of the vertices can be determined if and only if there is a complete edge or a complete arc lying on a quadrant. This algorithm is nonconservative in the sense that if the value-set boundary of an interval plant is exactly known, and particularly its vertices, then the Kharitonov rectangles are exactly those used to obtain these value sets.

  12. Frequency encoding in renal blood flow regulation

    DEFF Research Database (Denmark)

    Marsh, D.J.; Sosnovtseva, Olga; Pavlov, A.N.

    2005-01-01

    With a model of renal blood flow regulation, we examined consequences of tubuloglomerular feedback (TGF) coupling to the myogenic mechanism via voltage-gated Ca channels. The model reproduces the characteristic oscillations of the two mechanisms and predicts frequency and amplitude modulation...... of the myogenic oscillation by TGF. Analysis by wavelet transforms of single-nephron blood flow confirms that both amplitude and frequency of the myogenic oscillation are modulated by TGF. We developed a double-wavelet transform technique to estimate modulation frequency. Median value of the ratio of modulation...... TGF cycle to the next. We used a blood pressure signal recorded by telemetry from a conscious rat as the input to the model. Blood pressure fluctuations induced variability in the modulation records similar to those found in the nephron blood flow results. Frequency and amplitude modulation can...

  13. Low-frequency sound exposure causes reversible long-term changes of cochlear transfer characteristics.

    Science.gov (United States)

    Drexl, Markus; Otto, Larissa; Wiegrebe, Lutz; Marquardt, Torsten; Gürkov, Robert; Krause, Eike

    2016-02-01

    Intense, low-frequency sound presented to the mammalian cochlea induces temporary changes of cochlear sensitivity, for which the term 'Bounce' phenomenon has been coined. Typical manifestations are slow oscillations of hearing thresholds or the level of otoacoustic emissions. It has been suggested that these alterations are caused by changes of the mechano-electrical transducer transfer function of outer hair cells (OHCs). Shape estimates of this transfer function can be derived from low-frequency-biased distortion product otoacoustic emissions (DPOAE). Here, we tracked the transfer function estimates before and after triggering a cochlear Bounce. Specifically, cubic DPOAEs, modulated by a low-frequency biasing tone, were followed over time before and after induction of the cochlear Bounce. Most subjects showed slow, biphasic changes of the transfer function estimates after low-frequency sound exposure relative to the preceding control period. Our data show that the operating point changes biphasically on the transfer function with an initial shift away from the inflection point followed by a shift towards the inflection point before returning to baseline values. Changes in transfer function and operating point lasted for about 180 s. Our results are consistent with the hypothesis that intense, low-frequency sound disturbs regulatory mechanisms in OHCs. The homeostatic readjustment of these mechanisms after low-frequency offset is reflected in slow oscillations of the estimated transfer functions. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Single Platform Geolocation of Radio Frequency Emitters

    Science.gov (United States)

    2015-03-26

    shown in Figure 2.1. The ECEF frame is a geocentric right handed 3D Cartesian coordinate system with the origin at the center of mass of the Earth. The...an iterative non-linear weighted least squares approach which has been shown to produce more accurate estimates of an emitter’s location than the LS...frequency CRLB over the range of N and η values. At low values of N and η, the MLE variance approaches a value of 12/12 = 8.33 × 10−2, which is the

  15. Graphics processing units accelerated semiclassical initial value representation molecular dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Tamascelli, Dario; Dambrosio, Francesco Saverio [Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy); Conte, Riccardo [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States); Ceotto, Michele, E-mail: michele.ceotto@unimi.it [Dipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, 20133 Milano (Italy)

    2014-05-07

    This paper presents a Graphics Processing Units (GPUs) implementation of the Semiclassical Initial Value Representation (SC-IVR) propagator for vibrational molecular spectroscopy calculations. The time-averaging formulation of the SC-IVR for power spectrum calculations is employed. Details about the GPU implementation of the semiclassical code are provided. Four molecules with an increasing number of atoms are considered and the GPU-calculated vibrational frequencies perfectly match the benchmark values. The computational time scaling of two GPUs (NVIDIA Tesla C2075 and Kepler K20), respectively, versus two CPUs (Intel Core i5 and Intel Xeon E5-2687W) and the critical issues related to the GPU implementation are discussed. The resulting reduction in computational time and power consumption is significant and semiclassical GPU calculations are shown to be environment friendly.

  16. Relation of Cloud Occurrence Frequency, Overlap, and Effective Thickness Derived from CALIPSO and CloudSat Merged Cloud Vertical Profiles

    Science.gov (United States)

    Kato, Seiji; Sun-Mack, Sunny; Miller, Walter F.; Rose, Fred G.; Chen, Yan; Minnis, Patrick; Wielicki, Bruce A.

    2009-01-01

    A cloud frequency of occurrence matrix is generated using merged cloud vertical profile derived from Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and Cloud Profiling Radar (CPR). The matrix contains vertical profiles of cloud occurrence frequency as a function of the uppermost cloud top. It is shown that the cloud fraction and uppermost cloud top vertical pro les can be related by a set of equations when the correlation distance of cloud occurrence, which is interpreted as an effective cloud thickness, is introduced. The underlying assumption in establishing the above relation is that cloud overlap approaches the random overlap with increasing distance separating cloud layers and that the probability of deviating from the random overlap decreases exponentially with distance. One month of CALIPSO and CloudSat data support these assumptions. However, the correlation distance sometimes becomes large, which might be an indication of precipitation. The cloud correlation distance is equivalent to the de-correlation distance introduced by Hogan and Illingworth [2000] when cloud fractions of both layers in a two-cloud layer system are the same.

  17. Consumer Product Perceptions and Salmon Consumption Frequency: The Role of Heterogeneity Based on Food Lifestyle Segments

    OpenAIRE

    Yuko Onozaka; Håvard Hansen; Arne Sørvig

    2014-01-01

    Seafood consumers are vastly heterogeneous in terms of their knowledge, confidence, and perceptions about seafood. This article examines the relationship between consumer perceptions (healthiness, value for money, and convenience) and salmon consumption frequencies while modeling unobserved consumer heterogeneity by segmenting consumers based on their food-related lifestyle. We employ latent class analysis (LCA) that embeds the structural equation modeling (SEM) to ensure the latent nature of...

  18. Solar Radius at Subterahertz Frequencies and Its Relation to Solar Activity

    Science.gov (United States)

    Menezes, Fabian; Valio, Adriana

    2017-12-01

    The Sun emits radiation at several wavelengths of the electromagnetic spectrum. In the optical band, the solar radius is 695 700 km, and this defines the photosphere, which is the visible surface of the Sun. However, as the altitude increases, the electromagnetic radiation is produced at other frequencies, causing the solar radius to change as a function of wavelength. These measurements enable a better understanding of the solar atmosphere, and the radius dependence on the solar cycle is a good indicator of the changes that occur in the atmospheric structure. We measure the solar radius at the subterahertz frequencies of 0.212 and 0.405 THz, which is the altitude at which these emissions are primarily generated, and also analyze the radius variation over the 11-year solar activity cycle. For this, we used radio maps of the solar disk for the period between 1999 and 2017, reconstructed from daily scans made by the Solar Submillimeter-wave Telescope (SST), installed at El Leoncito Astronomical Complex (CASLEO) in the Argentinean Andes. Our measurements yield radii of 966.5'' ±2.8'' for 0.2 THz and 966.5'' ±2.7'' for 0.4 THz. This implies a height of 5.0 ±2.0 ×106 m above the photosphere. Furthermore, we also observed a strong anticorrelation between the radius variation and the solar activity at both frequencies.

  19. Simultaneously Suppressing Low-Frequency and Relaxation Oscillation Intensity Noise in a DBR Single-Frequency Phosphate Fiber Laser

    International Nuclear Information System (INIS)

    Xiao Yu; Li Can; Xu Shan-Hui; Feng Zhou-Ming; Yang Chang-Sheng; Zhao Qi-Lai; Yang Zhong-Min

    2015-01-01

    Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20 dB from 0.2 to 5kHz and over 10 dB from 5 to 10 kHz. The relaxation oscillation peak is suppressed by 22 dB. In addition, a long term (24 h) laser instability of less than 0.05% is achieved. (paper)

  20. Untangling the relative contribution of maltreatment severity and frequency to type of behavioral outcome in foster youth.

    Science.gov (United States)

    Jackson, Yo; Gabrielli, Joy; Fleming, Kandace; Tunno, Angela M; Makanui, P Kalani

    2014-07-01

    Within maltreatment research, type, frequency, and severity of abuse are often confounded and not always specifically documented. The result is samples that are often heterogeneous in regard to maltreatment experience, and the role of the different components of maltreatment in predicting outcome is unclear. The purpose of the present study was to identify and test the potential unique role of type, frequency, and severity of maltreatment to elucidate each variable's role in predicting outcome behavior. Data from 309 youth in foster care (ages 8-22) and their caregivers were collected using the Modified Maltreatment Classification System and the Behavioral Assessment System for Children, 2nd Edition (BASC2), to measure maltreatment exposure and behavioral outcome respectively. A measurement model of the BASC2 was completed to determine model fit within the sample data. A second confirmatory factor analysis (CFA) was completed to determine the unique contributions of frequency and severity of maltreatment across four types of abuse to externalizing, internalizing, and adaptive behavior. The result of the CFA determined good fit of the BASC2 to the sample data after a few modifications. The result of the second CFA indicated that the paths from severity to externalizing behavior and adaptive behavior (reverse loading) were significant. Paths from frequency of abuse were not predictive of behavioral outcome. Maltreatment is a complex construct and researchers are encouraged to examine components of abuse that may be differentially related to outcome behavior for youth. Untangling the multifaceted nature of abuse is important and may have implications for identifying specific outcomes for youth exposed to maltreatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Better Resolved Low Frequency Dispersions by the Apt Use of Kramers-Kronig Relations, Differential Operators, and All-In-1 Modeling

    NARCIS (Netherlands)

    van Turnhout, J.

    2016-01-01

    The dielectric spectra of colloidal systems often contain a typical low frequency dispersion, which usually remains unnoticed, because of the presence of strong conduction losses. The KK relations offer a means for converting ε′ into ε″ data. This allows us to calculate conduction free ε″ spectra in

  2. Low frequency ac conduction and dielectric relaxation in poly(N ...

    Indian Academy of Sciences (India)

    Unknown

    polymer chain in the form of bands analogous to that of a semiconductor and the ... these materials a model has been proposed which suggests the application of two .... values is almost equal to dc conductivity value while in high frequency ...

  3. Wave dispersion relations in two-dimensional Yukawa systems

    International Nuclear Information System (INIS)

    Liu Yanhong; Liu Bin; Chen Yanping; Yang Size; Wang Long; Wang Xiaogang

    2003-01-01

    Collective modes in a two-dimensional Yukawa system are investigated by molecular dynamics simulation in a wide range of coupling parameter Γ and screening strength κ. The dispersion relations and sound speeds of the transverse and longitudinal waves obtained for hexagonal lattice are in agreement with the theoretical results. The negative dispersion of the longitudinal wave is demonstrated. Frequency gaps are found on the dispersion curves of the transverse wave due to scattering of the waves on lattice defects for proper values of Γ. The common frequency of transverse and longitudinal waves drops dramatically with the increasing screening strength κ

  4. Like/dislike analysis using EEG: determination of most discriminative channels and frequencies.

    Science.gov (United States)

    Yılmaz, Bülent; Korkmaz, Sümeyye; Arslan, Dilek Betül; Güngör, Evrim; Asyalı, Musa H

    2014-02-01

    In this study, we have analyzed electroencephalography (EEG) signals to investigate the following issues, (i) which frequencies and EEG channels could be relatively better indicators of preference (like or dislike decisions) of consumer products, (ii) timing characteristic of "like" decisions during such mental processes. For this purpose, we have obtained multichannel EEG recordings from 15 subjects, during total of 16 epochs of 10 s long, while they were presented with some shoe photographs. When they liked a specific shoe, they pressed on a button and marked the time of this activity and the particular epoch was labeled as a LIKE case. No button press meant that the subject did not like the particular shoe that was displayed and corresponding epoch designated as a DISLIKE case. After preprocessing, power spectral density (PSD) of EEG data was estimated at different frequencies (4, 5, …, 40 Hz) using the Burg method, for each epoch corresponding to one shoe presentation. Each subject's data consisted of normalized PSD values (NPVs) from all LIKE and DISLIKE cases/epochs coming from all 19 EEG channels. In order to determine the most discriminative frequencies and channels, we have utilized logistic regression, where LIKE/DISLIKE status was used as a categorical (binary) response variable and corresponding NPVs were the continuously valued input variables or predictors. We observed that when all the NPVs (total of 37) are used as predictors, the regression problem was becoming ill-posed due to large number of predictors (compared to the number of samples) and high correlation among predictors. To circumvent this issue, we have divided the frequency band into low frequency (LF) 4-19 Hz and high frequency (HF) 20-40 Hz bands and analyzed the influence of the NPV in these bands separately. Then, using the p-values that indicate how significantly estimated predictor weights are different than zero, we have determined the NPVs and channels that are more influential

  5. Measurement of the 1S-2S frequency in atomic hydrogen

    International Nuclear Information System (INIS)

    Hildum, E.A.

    1986-01-01

    A first precise measurement of the 1S-2S energy interval in atomic hydrogen was obtained by observing the 1S-2S transition in an atomic beam by pulsed Doppler-free two-photon spectroscopy and using an interferometrically calibrated line of 130 Te 2 at 486 nm as the references. The measured 1S-2S frequency is 2,466,061 395.6(4.9)MHz. With the calculated 1S Lamb shift, the 1S-2S frequency yields a value for the Rydberg constant, R/sub ∞/ = 109,737.314 92(22) cm -1 , which is not in good agreement with the most recent previously measured value, 109,737.315 44(11) cm -1 , obtained by S.R. Amin et al. It is, however, in good agreement with a previous Rydberg value, 109,737.315 04(32) cm -1 , measured by J.E.M. Goldsmith. If the Rydberg constant is taken as given, the 1S-2S frequency determines a value for the 1S Lamb shift. With Amin's Rydberg, the measured Lamb shift is 8161.0(5.4) MHz, in poor agreement with the theoretical value of 8149.43(8) MHz. With Goldsmith's Rydberg, the measurement Lamb shift is 8151.0(8.7) MHz, in good agreement with theory

  6. Regional Frequency and Uncertainty Analysis of Extreme Precipitation in Bangladesh

    Science.gov (United States)

    Mortuza, M. R.; Demissie, Y.; Li, H. Y.

    2014-12-01

    Increased frequency of extreme precipitations, especially those with multiday durations, are responsible for recent urban floods and associated significant losses of lives and infrastructures in Bangladesh. Reliable and routinely updated estimation of the frequency of occurrence of such extreme precipitation events are thus important for developing up-to-date hydraulic structures and stormwater drainage system that can effectively minimize future risk from similar events. In this study, we have updated the intensity-duration-frequency (IDF) curves for Bangladesh using daily precipitation data from 1961 to 2010 and quantified associated uncertainties. Regional frequency analysis based on L-moments is applied on 1-day, 2-day and 5-day annual maximum precipitation series due to its advantages over at-site estimation. The regional frequency approach pools the information from climatologically similar sites to make reliable estimates of quantiles given that the pooling group is homogeneous and of reasonable size. We have used Region of influence (ROI) approach along with homogeneity measure based on L-moments to identify the homogenous pooling groups for each site. Five 3-parameter distributions (i.e., Generalized Logistic, Generalized Extreme value, Generalized Normal, Pearson Type Three, and Generalized Pareto) are used for a thorough selection of appropriate models that fit the sample data. Uncertainties related to the selection of the distributions and historical data are quantified using the Bayesian Model Averaging and Balanced Bootstrap approaches respectively. The results from this study can be used to update the current design and management of hydraulic structures as well as in exploring spatio-temporal variations of extreme precipitation and associated risk.

  7. Low-frequency coding variants in CETP and CFB are associated with susceptibility of exudative age-related macular degeneration in the Japanese population.

    Science.gov (United States)

    Momozawa, Yukihide; Akiyama, Masato; Kamatani, Yoichiro; Arakawa, Satoshi; Yasuda, Miho; Yoshida, Shigeo; Oshima, Yuji; Mori, Ryusaburo; Tanaka, Koji; Mori, Keisuke; Inoue, Satoshi; Terasaki, Hiroko; Yasuma, Tetsuhiro; Honda, Shigeru; Miki, Akiko; Inoue, Maiko; Fujisawa, Kimihiko; Takahashi, Kanji; Yasukawa, Tsutomu; Yanagi, Yasuo; Kadonosono, Kazuaki; Sonoda, Koh-Hei; Ishibashi, Tatsuro; Takahashi, Atsushi; Kubo, Michiaki

    2016-11-15

    Age-related macular degeneration (AMD) is a major cause of blindness in the elderly. Previous sequencing studies of AMD susceptibility genes have revealed the association of rare coding variants in CFH, CFI, C3 and C9 in European population; however, the impact of rare or low-frequency coding variants on AMD susceptibility in other populations is largely unknown. To identify the role of low-frequency coding variants on exudative AMD susceptibility in a Japanese population, we analysed the association of coding variants of 34 AMD candidate genes in the two-stage design by a multiplex PCR-based target sequencing method. We used a total of 2,886 (1st: 827, 2nd: 2,059) exudative AMD cases including typical AMD, polypoidal choroidal vasculopathy, and retinal angiomatous proliferation and 9,337 (1st: 3,247 2nd: 6,090) controls. Gene-based analysis found a significant association of low-frequency variants (minor allele frequency (MAF) low-frequency variant (R74H) in CFB would be individually associated with AMD susceptibility independent of the GWAS associated SNP. These findings highlight the importance of target sequencing to reveal the impact of rare or low-frequency coding variants on disease susceptibility in different ethnic populations.

  8. Frequency domain design of gain scheduling control for large wind systems in full-load region

    International Nuclear Information System (INIS)

    Burlibaşa, A.; Ceangă, E.

    2014-01-01

    Highlights: • A large wind energy system, operating under full-load regime, is considered. • According to its particularities in frequency domain, control law design is provided. • These particularities are influenced by the interactions of wind–tower–blade ensemble. • Control low, within gain scheduling strategy, is achieved imposing stability reserve. • Supplementary a criterion, aimed at reducing mechanical loads, is imposed. - Abstract: The paper presents the issue of power control law synthesis, in the case of a large wind system that operates under full-load regime, based on dynamic properties details in frequency domain. Solving this problem involves two phases: the establishment of a linearized model as faithfully as possible in various operating points of the full-load region, and synthesis of the power controller, considered with classic structure, taking into account frequency particularities of the obtained linearized model. Obtained linear model of the controlled process is of order 16 and encloses subsystems for tower fore-aft oscillations damping, and for drive-train torsion oscillations damping. The designed controller contains a PI component and a lag compensator for dynamic correction at high frequencies. It is known that the main features of wind system dynamics generated by the interaction of wind–tower–blade ensemble cause a gap in the gain characteristic of the model and complex conjugate zeros, which can move between right and left half-planes, depending on the average wind speed value. Consequently, for control law synthesis an interactive frequency solution is adopted. This is “transparent” in relation to particularities induced by wind–tower–blade interaction. This solution allows evaluation of the extent to which control law is affected by the subsystem for tower oscillations damping. Given the strong dependence between the model and the mean wind speed value, a gain scheduling control law is designed. At

  9. Helper T lymphocyte precursor frequency analysis in alloreactivity detection

    International Nuclear Information System (INIS)

    Cukrova, V.; Dolezalova, L.; Loudova, M.; Vitek, A.

    1998-01-01

    The utility of IL-2 secreting helper T lymphocyte precursors (HTLp) frequency testing has been evaluated for detecting alloreactivity. The frequency of HTLp was approached by limiting dilution assay. High HTLp frequency was detected in 20 out of 30 HLA matched unrelated pairs (67%). The comparison of HTLp and CTLp (cytotoxic T lymphocyte precursors) frequencies in HLA matched unrelated pairs showed that the two examinations are not fully alternative in detecting alloreactivity. This could suggest the utility of combined testing of both HTLp and CTLp frequencies for alloreactivity assessment. In contrast, five positive HTLp values were only found among 28 HLA genotypic identical siblings (18%). Previous CTLp limiting dilution studies showed very low or undetectable CTLp frequency results in that group. For that, HTLp assay remains to be the only cellular in vitro technique detecting alloreactivity in these combinations. (authors)

  10. The Role of Parental Perceptions of Tic Frequency and Intensity in Predicting Tic-Related Functional Impairment in Youth with Chronic Tic Disorders

    OpenAIRE

    Espil, Flint M.; Capriotti, Matthew R.; Conelea, Christine A.; Woods, Douglas W.

    2014-01-01

    Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with Chronic Tic Disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic ...

  11. Higher frequency network activity flow predicts lower frequency node activity in intrinsic low-frequency BOLD fluctuations.

    Science.gov (United States)

    Bajaj, Sahil; Adhikari, Bhim Mani; Dhamala, Mukesh

    2013-01-01

    The brain remains electrically and metabolically active during resting conditions. The low-frequency oscillations (LFO) of the blood oxygen level-dependent (BOLD) signal of functional magnetic resonance imaging (fMRI) coherent across distributed brain regions are known to exhibit features of this activity. However, these intrinsic oscillations may undergo dynamic changes in time scales of seconds to minutes during resting conditions. Here, using wavelet-transform based time-frequency analysis techniques, we investigated the dynamic nature of default-mode networks from intrinsic BOLD signals recorded from participants maintaining visual fixation during resting conditions. We focused on the default-mode network consisting of the posterior cingulate cortex (PCC), the medial prefrontal cortex (mPFC), left middle temporal cortex (LMTC) and left angular gyrus (LAG). The analysis of the spectral power and causal flow patterns revealed that the intrinsic LFO undergo significant dynamic changes over time. Dividing the frequency interval 0 to 0.25 Hz of LFO into four intervals slow-5 (0.01-0.027 Hz), slow-4 (0.027-0.073 Hz), slow-3 (0.073-0.198 Hz) and slow-2 (0.198-0.25 Hz), we further observed significant positive linear relationships of slow-4 in-out flow of network activity with slow-5 node activity, and slow-3 in-out flow of network activity with slow-4 node activity. The network activity associated with respiratory related frequency (slow-2) was found to have no relationship with the node activity in any of the frequency intervals. We found that the net causal flow towards a node in slow-3 band was correlated with the number of fibers, obtained from diffusion tensor imaging (DTI) data, from the other nodes connecting to that node. These findings imply that so-called resting state is not 'entirely' at rest, the higher frequency network activity flow can predict the lower frequency node activity, and the network activity flow can reflect underlying structural

  12. Resonant-frequency discharge in a multi-cell radio frequency cavity

    International Nuclear Information System (INIS)

    Popović, S.; Upadhyay, J.; Nikolić, M.; Vušković, L.; Mammosser, J.

    2014-01-01

    We are reporting experimental results on a microwave discharge operating at resonant frequency in a multi-cell radio frequency (RF) accelerator cavity. Although the discharge operated at room temperature, the setup was constructed so that it could be used for plasma generation and processing in fully assembled active superconducting radio-frequency cryo-module. This discharge offers a mechanism for removal of a variety of contaminants, organic or oxide layers, and residual particulates from the interior surface of RF cavities through the interaction of plasma-generated radicals with the cavity walls. We describe resonant RF breakdown conditions and address the issues related to resonant detuning due to sustained multi-cell cavity plasma. We have determined breakdown conditions in the cavity, which was acting as a plasma vessel with distorted cylindrical geometry. We discuss the spectroscopic data taken during plasma removal of contaminants and use them to evaluate plasma parameters, characterize the process, and estimate the volatile contaminant product removal

  13. Resonant-frequency discharge in a multi-cell radio frequency cavity

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, S; Upadhyay, J; Mammosser, J; Nikolic, M; Vuskovic, L

    2014-11-07

    We are reporting experimental results on microwave discharge operating at resonant frequency in a multi-cell radio frequency (RF) accelerator cavity. Although the discharge operated at room temperature, the setup was constructed so that it could be used for plasma generation and processing in fully assembled active superconducting radio-frequency (SRF) cryomodule (in situ operation). This discharge offers an efficient mechanism for removal of a variety of contaminants, organic or oxide layers, and residual particulates from the interior surface of RF cavities through the interaction of plasma-generated radicals with the cavity walls. We describe resonant RF breakdown conditions and address the problems related to generation and sustaining the multi-cell cavity plasma, which are breakdown and resonant detuning. We have determined breakdown conditions in the cavity, which was acting as a plasma vessel with distorted cylindrical geometry. We discuss the spectroscopic data taken during plasma removal of contaminants and use them to evaluate plasma parameters, characterize the process, and estimate the volatile contaminant product removal.

  14. Testing hypotheses on frequency effects in first language acquisition

    DEFF Research Database (Denmark)

    Kjærbæk, Laila; Basbøll, Hans

    2015-01-01

    On the basis of extensive literature studies, Ambridge, Kidd, Rowland and Theakston (2015) present five theses on frequency effects on language acquisition: i) the Levels and Kinds Thesis argues that frequency effects exist at all levels and are of many different kinds (e.g., type and token...... frequency effects as well as absolute and relative frequency effects); ii) the Age of Acquisition Thesis argues that all other things being equal, frequent forms will be acquired before less frequent forms. Since all other things are not equal, this claim does not entail a one-to-one relationship between...... frequency and age of acquisition; iii) the Prevent Error Thesis argues that high-frequency forms prevent (or reduce) errors in contexts in which they are the target; iv) the Cause Error Thesis argues that high-frequency forms also cause errors in contexts in which a competing, related lower-frequency form...

  15. High frequency dynamics in centrifugal compressors

    NARCIS (Netherlands)

    Twerda, A.; Meulendijks, D.; Smeulers, J.P.M.; Handel, R. van den; Lier, L.J. van

    2008-01-01

    Problems with centrifugal compressors relating to high frequency, i.e. Blade passing frequency (BPF) are increasing. Pulsations and vibrations generated in centrifugal compressors can lead to nuisance, due to strong tonal noise, and even breakdown. In several cases the root cause of a failure or a

  16. High resolution electromagnetic methods and low frequency dispersion of rock conductivity

    OpenAIRE

    Svetov, B. S.; Ageev, V. V.

    1999-01-01

    The influence of frequency dispersion of conductivity (induced polarization) of rocks on the results of electromagnetic (EM) sounding was studied on the basis of calculation of electric field of vertical magnetic dipole above horizontally layered polarizable sections. Frequency dispersion was approximated by the Debye formula. Polarizable homogeneous halfspace, two, three and multilayered sections were analyzed in frequency and time domains. The calculations for different values of chargeabil...

  17. Temperature, Frequency, and Young’s Modulus of an Aluminum Tuning Fork

    Directory of Open Access Journals (Sweden)

    Zachery L. Greer

    2011-01-01

    Full Text Available The frequency produced by a standard C (523.3 Hz aluminum alloy tuning fork when struck at temperatures ranging from 29 ̊C to 300 ̊C was studied. It was found that frequency decreased with increasing temperature with an inverse exponential relationship. The frequency was used to calculate Young’s Modulus for aluminum, with the results being in close agreement with published values.

  18. Measuring value sensitivity in medicine.

    Science.gov (United States)

    Ineichen, Christian; Christen, Markus; Tanner, Carmen

    2017-01-28

    Value sensitivity - the ability to recognize value-related issues when they arise in practice - is an indispensable competence for medical practitioners to enter decision-making processes related to ethical questions. However, the psychological competence of value sensitivity is seldom an explicit subject in the training of medical professionals. In this contribution, we outline the traditional concept of moral sensitivity in medicine and its revised form conceptualized as value sensitivity and we propose an instrument that measures value sensitivity. We developed an instrument for assessing the sensitivity for three value groups (moral-related values, values related to the principles of biomedical ethics, strategy-related values) in a four step procedure: 1) value identification (n = 317); 2) value representation (n = 317); 3) vignette construction and quality evaluation (n = 37); and 4) instrument validation by comparing nursing professionals with hospital managers (n = 48). We find that nursing professionals recognize and ascribe importance to principle-related issues more than professionals from hospital management. The latter are more likely to recognize and ascribe importance to strategy-related issues. These hypothesis-driven results demonstrate the discriminatory power of our newly developed instrument, which makes it useful not only for health care professionals in practice but for students and people working in the clinical context as well.

  19. Glottal volume velocity waveform characteristics in subjects with and without vocal training, related to gender, sound intensity, fundamental frequency, and age

    NARCIS (Netherlands)

    Sulter, AM; Wit, HP

    Glottal volume velocity waveform characteristics of 224 subjects, categorized in four groups according to gender and vocal training, were determined, and their relations to sound-pressure level, fundamental frequency, intra-oral pressure, and age were analyzed. Subjects phonated at three intensity

  20. Glottal volume velocity waveform characteristics in subjects with and without vocal training, related to gender, sound intensity, fundamental frequency, and age

    NARCIS (Netherlands)

    Sulter, AM; Wit, HP

    1996-01-01

    Glottal volume velocity waveform characteristics of 224 subjects, categorized in four groups according to gender and vocal training, were determined, and their relations to sound-pressure level, fundamental frequency, intra-oral pressure, and age were analyzed. Subjects phonated at three intensity

  1. Susceptibility of CoFeB/AlOx/Co Magnetic Tunnel Junctions to Low-Frequency Alternating Current

    Directory of Open Access Journals (Sweden)

    Yuan-Tsung Chen

    2013-10-01

    Full Text Available This investigation studies CoFeB/AlOx/Co magnetic tunneling junction (MTJ in the magnetic field of a low-frequency alternating current, for various thicknesses of the barrier layer AlOx. The low-frequency alternate-current magnetic susceptibility (χac and phase angle (θ of the CoFeB/AlOx/Co MTJ are determined using an cac analyzer. The driving frequency ranges from 10 to 25,000 Hz. These multilayered MTJs are deposited on a silicon substrate using a DC and RF magnetron sputtering system. Barrier layer thicknesses are 22, 26, and 30 Å. The X-ray diffraction patterns (XRD include a main peak at 2θ = 44.7° from hexagonal close-packed (HCP Co with a highly (0002 textured structure, with AlOx and CoFeB as amorphous phases. The full width at half maximum (FWHM of the Co(0002 peak, decreases as the AlOx thickness increases; revealing that the Co layer becomes more crystalline with increasing thickness. χac result demonstrates that the optimal resonance frequency (fres that maximizes the χac value is 500 Hz. As the frequency increases to 1000 Hz, the susceptibility decreases rapidly. However, when the frequency increases over 1000 Hz, the susceptibility sharply declines, and almost closes to zero. The experimental results reveal that the mean optimal susceptibility is 1.87 at an AlOx barrier layer thickness of 30 Å because the Co(0002 texture induces magneto-anisotropy, which improves the indirect CoFeB and Co spin exchange-coupling strength and the χac value. The results concerning magnetism indicate that the magnetic characteristics are related to the crystallinity of Co.

  2. Use value, exchange value, and resource scarcity

    International Nuclear Information System (INIS)

    Stern, D.I.

    1999-01-01

    The literature on natural resource scarcity indicators is reviewed. Scarcity indicators can be classified by what is being measured: value of the resource stock or value of extracted resource commodities; whose value is considered: social vs. private scarcity; and by the mode of valuation considered: exchange value and use value. Prices and rents are common measures of exchange value or indicators of ''exchange scarcity'' and unit costs can be seen as use value indicators or indicators of u se scarcity . The major aim of this paper is to demonstrate the links between productivity indicators such as unit costs and the classical concept of use value. The two classes of indicator relate to John Commons' discussions of scarcity and efficiency, and a marginal vs. a non-marginal approach to value and scarcity. The classical use value concept also has wider relevance for issues of valuation in energy, resource, and environmental policy. (author)

  3. Global trends in critical values practices and their harmonization.

    Science.gov (United States)

    Kost, Gerald J; Hale, Kristin N

    2011-02-01

    The objectives of this article were 1) to identify current trends in critical values practices in North America, Europe, and other regions; 2) to describe progress toward harmonization of critical limits; and 3) to synthesize strategies that will encourage global consensus. Critical limits are described in national surveys. Critical value practices are guided by federal statutes, The Joint Commission regulations, and accreditation requirements in the US; by provincial healthcare agencies in Canada; by thought leaders and ISO EN 15189:2007 in Europe; and in SE Asia, mostly by ad hoc policies lacking statutory grip. Review of databases, literature, websites, federal statutes, litigation, official policies, current affairs, and accreditation agency requirements. Practical strategies will accelerate harmonization of critical values practices, as follows: a) continue national and international survey comparisons; b) clarify age, ethnic, and subject dependencies; c) standardize qualitative and quantitative decision levels for urgent clinician notification; d) monitor compliance and timeliness for safety; and e) alert high frequencies of critical values related to adverse events. New expectations and communication technologies present opportunities for enhanced performance using wireless closed-loop reporting with recipient acknowledgment to reduce phone calls and improve efficiency. Hospitals worldwide can benefit from developing consensus for critical values practices.

  4. Predictive value of object relations for therapeutic alliance and outcome in psychotherapy for depression: an exploratory study

    NARCIS (Netherlands)

    Van, H.L.; Hendriksen, M.; Schoevers, R.A.; Peen, J.; Abraham, R.A.; Dekker, J.J.M.

    2008-01-01

    The concept of object relations has been shown to be relevant for the process and outcome of psychodynamic psychotherapies. However, little is known about its relevance for the psychotherapeutic treatment of depression. In this study, we explored the predictive value of object relational functioning

  5. Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current in the prese......Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current...

  6. Numerical Study of Frequency-dependent Seismoelectric Coupling in Partially-saturated Porous Media

    Directory of Open Access Journals (Sweden)

    Djuraev Ulugbek

    2017-01-01

    Full Text Available The seismoelectric phenomenon associated with propagation of seismic waves in fluid-saturated porous media has been studied for many decades. The method has a great potential to monitor subsurface fluid saturation changes associated with production of hydrocarbons. Frequency of the seismic source has a significant impact on measurement of the seismoelectric effects. In this paper, the effects of seismic wave frequency and water saturation on the seismoelectric response of a partially-saturated porous media is studied numerically. The conversion of seismic wave to electromagnetic wave was modelled by extending the theoretically developed seismoelectric coupling coefficient equation. We assumed constant values of pore radius and zeta-potential of 80 micrometers and 48 microvolts, respectively. Our calculations of the coupling coefficient were conducted at various water saturation values in the frequency range of 10 kHz to 150 kHz. The results show that the seismoelectric coupling is frequency-dependent and decreases exponentially when frequency increases. Similar trend is seen when water saturation is varied at different frequencies. However, when water saturation is less than about 0.6, the effect of frequency is significant. On the other hand, when the water saturation is greater than 0.6, the coupling coefficient shows monotonous trend when water saturation is increased at constant frequency.

  7. Whispering gallery mode resonators for frequency metrology applications

    Science.gov (United States)

    Baumgartel, Lukas

    This dissertation describes an investigation into the use of whispering gallery mode (WGM) resonators for applications towards frequency reference and metrology. Laser stabilization and the measurement of optical frequencies have enabled myriad technologies of both academic and commercial interest. A technology which seems to span both motivations is optical atomic clocks. These devices are virtually unimaginable without the ultra stable lasers plus frequency measurement and down-conversion afforded by Fabry Perot (FP) cavities and model-locked laser combs, respectively. However, WGM resonators can potentially perform both of these tasks while having the distinct advantages of compactness and simplicity. This work represents progress towards understanding and mitigating the performance limitations of WGM cavities for such applications. A system for laser frequency stabilization to a the cavity via the Pound-Drever-Hall (PDH) method is described. While the laser lock itself is found to perform at the level of several parts in 1015, a variety of fundamental and technical mechanisms destabilize the WGM frequency itself. Owing to the relatively large thermal expansion coefficients in optical crystals, environmental temperature drifts set the stability limit at time scales greater than the thermal relaxation time of the crystal. Uncompensated, these drifts pull WGM frequencies about 3 orders of magnitude more than they would in an FP cavity. Thus, two temperature compensation schemes are developed. An active scheme measures and stabilizes the mode volume temperature to the level of several nK, reducing the effective temperature coefficient of the resonator to 1.7x10-7 K-1; simulations suggest that the value could eventually be as low as 3.5x10-8 K-1, on par with the aforementioned FP cavities. A second, passive scheme is also described, which employs a heterogeneous resonator structure that capitalizes on the thermo-mechanical properties of one material and the optical

  8. Task-related modulations of BOLD low-frequency fluctuations within the default mode network

    Science.gov (United States)

    Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Eid Assan, Ibrahim; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico

    2017-07-01

    Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33±6 years, 8F/12M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the steady-state execution of a sustained working memory n-back task. We found that the steady state execution of such a task impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to steady-state task execution, can contribute to a better understanding of how brain networks rearrange themselves in response of a task.

  9. Odd-frequency pairing in superconducting heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Golubov, A A [Faculty of Science and Technology and MESA Institute for Nanotechnology, University of Twente, 7500 AE Enschede (Netherlands); Tanaka, Y [Department of Applied Physics, Nagoya University, Nagoya, 464-8603 (Japan); Asano, Y [Department of Applied Physics, Hokkaido University, Sapporo 060-8628 (Japan); Tanuma, Y [Institute of Physics, Kanagawa University, 3-7-1, Rokkakubashi, Kanagawa-ku, Yokohama 221-8686 (Japan)], E-mail: a.golubov@utwente.nl

    2009-04-22

    We review the theory of odd-frequency pairing in superconducting heterostructures, where an odd-frequency pairing component is induced near interfaces. A general description of the superconducting proximity effect in a normal metal or a ferromagnet attached to an unconventional superconductor (S) is given within quasiclassical kinetic theory for various types of symmetry state in S. Various possible symmetry classes in a superconductor are considered which are consistent with the Pauli principle: even-frequency spin-singlet even-parity (ESE) state, even-frequency spin-triplet odd-parity (ETO) state, odd-frequency spin-triplet even-parity (OTE) state and odd-frequency spin-singlet odd-parity (OSO) state. As an example, we consider a junction between a diffusive normal metal (DN) and a p-wave superconductor (even-frequency spin-triplet odd-parity symmetry), where the pairing amplitude in DN belongs to an odd-frequency spin-triplet even-parity symmetry class. We also discuss the manifestation of odd-frequency pairing in conventional superconductor/normal (S/N) proximity systems and its relation to the classical McMillan-Rowell oscillations.

  10. Analysis of frequency effect on variegated RAM styles and other parameters using 40 nm FPGA

    DEFF Research Database (Denmark)

    Sharma, Rashmi; Pandey, Bishwajeet; Sharma, Vaashu

    2018-01-01

    . This analysis has been performed using the XILINX 12.1 and IBM SPSS Statistics 21 software and VHDL language. Pipe_distributed style at comparatively lesser values of frequencies consumes the least power. Therefore, lesser values of frequencies should be maintained while observing the power. This would bloom up...

  11. Mapping Meaningful Places on Washington's Olympic Peninsula: Toward a Deeper Understanding of Landscape Values.

    Science.gov (United States)

    Cerveny, Lee Karol; Biedenweg, Kelly; McLain, Rebecca

    2017-10-01

    Landscape values mapping has been widely employed as a form of public participation GIS (PPGIS) in natural resource planning and decision-making to capture the complex array of values, uses, and interactions between people and landscapes. A landscape values typology has been commonly employed in the mapping of social and environmental values in a variety of management settings and scales. We explore how people attribute meanings and assign values to special places on the Olympic Peninsula (Washington, USA) using both a landscape values typology and qualitative responses about residents' place-relationships. Using geographically referenced social values data collected in community meetings (n = 169), we identify high-frequency landscape values and examine how well the landscape values are reflected in open-ended descriptions of place-relations. We also explore the various interpretations of 14 landscape values used in the study. In particular, we investigate any overlapping meanings or blurriness among landscape values and reveal potentially emergent landscape values from the qualitative data. The results provide insights on the use of landscape values mapping typologies for practitioners and researchers engaged in the mapping of social values for PPGIS.

  12. Mapping Meaningful Places on Washington's Olympic Peninsula: Toward a Deeper Understanding of Landscape Values

    Science.gov (United States)

    Cerveny, Lee Karol; Biedenweg, Kelly; McLain, Rebecca

    2017-10-01

    Landscape values mapping has been widely employed as a form of public participation GIS (PPGIS) in natural resource planning and decision-making to capture the complex array of values, uses, and interactions between people and landscapes. A landscape values typology has been commonly employed in the mapping of social and environmental values in a variety of management settings and scales. We explore how people attribute meanings and assign values to special places on the Olympic Peninsula (Washington, USA) using both a landscape values typology and qualitative responses about residents' place-relationships. Using geographically referenced social values data collected in community meetings ( n = 169), we identify high-frequency landscape values and examine how well the landscape values are reflected in open-ended descriptions of place-relations. We also explore the various interpretations of 14 landscape values used in the study. In particular, we investigate any overlapping meanings or blurriness among landscape values and reveal potentially emergent landscape values from the qualitative data. The results provide insights on the use of landscape values mapping typologies for practitioners and researchers engaged in the mapping of social values for PPGIS.

  13. Fast frequency divider circuit using combinational logic

    Science.gov (United States)

    Helinski, Ryan

    2017-05-30

    The various technologies presented herein relate to performing on-chip frequency division of an operating frequency of a ring oscillator (RO). Per the various embodiments herein, a conflict between RO size versus operational frequency can be addressed by dividing the output frequency of the RO to a frequency that can be measured on-chip. A frequency divider circuit (comprising NOR gates and latches, for example) can be utilized in conjunction with the RO on the chip. In an embodiment, the frequency divider circuit can include a pair of latches coupled to the RO to facilitate dividing the oscillating frequency of the RO by 2. In another embodiment, the frequency divider circuit can include four latches (operating in pairs) coupled to the RO to facilitate dividing the oscillating frequency of the RO by 4. A plurality of ROs can be MUXed to the plurality of ROs by a single oscillation-counting circuit.

  14. Soil compaction related to grazing and its effects on herbaceous roots frequency and soil organic matter content in rangelands of SW Spain

    Science.gov (United States)

    Pulido, Manuel; Schnabel, Susanne; Francisco Lavado Contador, Joaquín; Miralles Mellado, Isabel

    2016-04-01

    Rangelands in SW Spain occupy a total surface area of approximately 6 million ha and constitute the most representative extensive ranching system of the Iberian Peninsula gathering more than 13 million livestock heads. They are characterised by an herbaceous layer, mostly composed of therophytic species, with a disperse tree cover, mainly holm oak and cork oak (Quercus ilex rotundifolia and Q. suber), interspersed with shrubs in many places. This type of land system is of ancient origin and experienced frequent changes in land use in the past, since agricultural, livestock and forestry activities have coexisted within the same farms. In recent decades, livestock farming has become dominant due, in part, to the subsidies of the Common Agriculture Policy. Since Spain joined the European Union in 1986 until the year 2000, the number of domestic animals doubled, particularly cattle, and consequently animal stocking rates have increased on average from 0.40 AU ha-1 up to 0.70 AU ha-1. This increase in animal stocking rates, along with a progressive substitution of cattle instead of sheep in many farms, has led to the occurrence of land degradation processes such as the reduction of grass cover or soil compaction in heavily grazed areas. Previous research has evidenced higher values of soil bulk density and resistance to penetration as well as larger bare surface areas in spring in fenced areas with animal stocking rates above 1 AU ha-1. However, a better understanding of how increasing bulk density or resistance to penetration influence the frequency of herbaceous roots and how a reduction in the frequency of roots affects soil organic matter content in rangelands is still unknown. Therefore, the main goal of this study was to determine possible relationships between the frequencies of herbaceous roots and soil organic matter content in order to understand the effect of excessive animal numbers on the depletion of soil fertility by reducing progressively the quantity of

  15. Estimation and applicability of attenuation characteristics for source parameters and scaling relations in the Garhwal Kumaun Himalaya region, India

    Science.gov (United States)

    Singh, Rakesh; Paul, Ajay; Kumar, Arjun; Kumar, Parveen; Sundriyal, Y. P.

    2018-06-01

    Source parameters of the small to moderate earthquakes are significant for understanding the dynamic rupture process, the scaling relations of the earthquakes and for assessment of seismic hazard potential of a region. In this study, the source parameters were determined for 58 small to moderate size earthquakes (3.0 ≤ Mw ≤ 5.0) occurred during 2007-2015 in the Garhwal-Kumaun region. The estimated shear wave quality factor (Qβ(f)) values for each station at different frequencies have been applied to eliminate any bias in the determination of source parameters. The Qβ(f) values have been estimated by using coda wave normalization method in the frequency range 1.5-16 Hz. A frequency-dependent S wave quality factor relation is obtained as Qβ(f) = (152.9 ± 7) f(0.82±0.005) by fitting a power-law frequency dependence model for the estimated values over the whole study region. The spectral (low-frequency spectral level and corner frequency) and source (static stress drop, seismic moment, apparent stress and radiated energy) parameters are obtained assuming ω-2 source model. The displacement spectra are corrected for estimated frequency-dependent attenuation, site effect using spectral decay parameter "Kappa". The frequency resolution limit was resolved by quantifying the bias in corner frequencies, stress drop and radiated energy estimates due to finite-bandwidth effect. The data of the region shows shallow focused earthquakes with low stress drop. The estimation of Zúñiga parameter (ε) suggests the partial stress drop mechanism in the region. The observed low stress drop and apparent stress can be explained by partial stress drop and low effective stress model. Presence of subsurface fluid at seismogenic depth certainly manipulates the dynamics of the region. However, the limited event selection may strongly bias the scaling relation even after taking as much as possible precaution in considering effects of finite bandwidth, attenuation and site corrections

  16. Differential effects of high-frequency versus low-frequency exercise training in rehabilitation of patients with coronary artery disease

    NARCIS (Netherlands)

    Nieuwland, W.; Berkhuysen, M.A.; van Veldhuisen, D.J.; Brugemann, J.; Landsman, M.L.J.; van Sonderen, E.; Lie, K.I.; Crijns, H.J.G.M.; Rispens, P.

    2000-01-01

    OBJECTIVES We sought to study the influence of frequency of exercise training during cardiac rehabilitation on functional capacity (i.e., peak oxygen consumption [VO2] and ventilatory anaerobic threshold [VAT]) and quality of life (QoL). BACKGROUND Although the value of cardiac rehabilitation is now

  17. On the undesired frequency chirping in photonic time-stretch systems

    Science.gov (United States)

    Xu, Yuxiao; Chi, Hao; Jin, Tao; Zheng, Shilie; Jin, Xiaofeng; Zhang, Xianmin

    2017-12-01

    The technique of photonic time stretch (PTS) has been intensively investigated in the past decade due to its potential in the acquisition of ultra-high speed signals. The frequency-related RF power fading in the PTS systems with double sideband (DSB) modulation has been well-known, which limits the maximum modulation frequency. Some solutions have been proposed to solve this problem. In this paper, we report another effect, i.e., undesired frequency chirping, which also relates to the performance degradation of PTS systems with DSB modulation, for the first time to our knowledge. Distinct from the nonlinearities caused by nonlinear modulation and square-law photodetection, which is common in radio frequency analog optical links, this frequency chirping originates from the addition of two beating signals with a relative delay after photodetection. A theoretical model for exactly describing the frequency chirping is presented, and is then verified by simulations. Discussion on the method to avoid the frequency chirping is also presented.

  18. Automatic Locking of Laser Frequency to an Absorption Peak

    Science.gov (United States)

    Koch, Grady J.

    2006-01-01

    An electronic system adjusts the frequency of a tunable laser, eventually locking the frequency to a peak in the optical absorption spectrum of a gas (or of a Fabry-Perot cavity that has an absorption peak like that of a gas). This system was developed to enable precise locking of the frequency of a laser used in differential absorption LIDAR measurements of trace atmospheric gases. This system also has great commercial potential as a prototype of means for precise control of frequencies of lasers in future dense wavelength-division-multiplexing optical communications systems. The operation of this system is completely automatic: Unlike in the operation of some prior laser-frequency-locking systems, there is ordinarily no need for a human operator to adjust the frequency manually to an initial value close enough to the peak to enable automatic locking to take over. Instead, this system also automatically performs the initial adjustment. The system (see Figure 1) is based on a concept of (1) initially modulating the laser frequency to sweep it through a spectral range that includes the desired absorption peak, (2) determining the derivative of the absorption peak with respect to the laser frequency for use as an error signal, (3) identifying the desired frequency [at the very top (which is also the middle) of the peak] as the frequency where the derivative goes to zero, and (4) thereafter keeping the frequency within a locking range and adjusting the frequency as needed to keep the derivative (the error signal) as close as possible to zero. More specifically, the system utilizes the fact that in addition to a zero crossing at the top of the absorption peak, the error signal also closely approximates a straight line in the vicinity of the zero crossing (see Figure 2). This vicinity is the locking range because the linearity of the error signal in this range makes it useful as a source of feedback for a proportional + integral + derivative control scheme that

  19. Multichannel linear descriptors analysis for event-related EEG of vascular dementia patients during visual detection task.

    Science.gov (United States)

    Lou, Wutao; Xu, Jin; Sheng, Hengsong; Zhao, Songzhen

    2011-11-01

    Multichannel EEG recorded in a task condition could contain more information about cognition. However, that has not been widely investigated in the vascular-dementia (VaD)- related studies. The purpose of this study was to explore the differences of brain functional states between VaD patients and normal controls while performing a detection task. Three multichannel linear descriptors, i.e. spatial complexity (Ω), field strength (Σ) and frequency of field changes (Φ), were applied to analyse four frequency bands (delta, theta, alpha and beta) of multichannel event-related EEG signals for 12 VaD patients (mean age ± SD: 69.25 ± 10.56 years ; MMSE score ± SD: 22.58 ± 4.42) and 12 age-matched healthy subjects (mean age ± SD: 67.17 ± 5.97 years ; MMSE score ± SD: 29.08 ± 0.9). The correlations between the three measures and MMSE scores were also analysed. VaD patients showed a significant higher Ω value in the delta (p = 0.013) and theta (p = 0.021) frequency bands, a lower Σ value (p = 0.011) and a higher Φ (p = 0.008) value in the delta frequency band compared with normal controls. The MMSE scores were negatively correlated with the Ω (r = -0.52, p = 0.01) and Φ (r = -0.47, p = 0.02) values in the delta frequency band. The results indicated the VaD patients presented a reduction of synchronization in the slow frequency band during target detection, and suggested more neurons might be activated in VaD patients compared with normal controls. The Ω and Φ measures in the delta frequency band might be used to evaluate the degree of cognitive dysfunction. The multichannel linear descriptors are promising measures to reveal the differences in brain functions between VaD patients and normal subjects, and could potentially be used to evaluate the degree of cognitive dysfunction in VaD patients. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Induced micro-mutations in rice - the frequency and spectrum of gamma ray induced height variations in rice variety-Jaya

    International Nuclear Information System (INIS)

    Nair, N.K.; Ninan, C.A.

    1975-01-01

    Seeds of rice variety, Jaya, treated with moderate doses of (10, 20 and 30 kR) gamma rays were subjected to study the relative magnitude of induced variability and the type of mutations induced for height of plant in M 2 and M 3 generations. Progenies of 3352 M 1 spikes, totalling to 35691 M 2 plants and their subsequent progenies in M 3 were analysed. To get wider variability, very large populations in all the generations were studied. The mean value, genetic variance and phenotypic frequency distribution with and between generations were studied. The treated population showed no significant shift in mean values from that of control. The variance was greater in the irradiated material compared to control. The variability was found to shift in both plus and minus direction from that of control with a higher frequency in the minus direction in M 2 . A high frequency of dwarf mutants was observed in 20 kR treated population in the M 2 generation. The segregation ratio was higher in M 2 compared to M 3 generation. (author)