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1

Utility Maximization: Framework and Applications  

Microsoft Academic Search

Network utility maximization (NUM) problem formulations provide an important approach to conduct network resource allocation and to view layering as optimization decomposition. In the existing literature, distributed implementations are typically achieved by means of the so-called dual decomposition technique. However, the span of decomposition possibilities includes many other elements that thus far have not been fully exploited, such as the

Daniel P. Palomar; Mung Chiang

2

Expected utility with lower probabilities  

Microsoft Academic Search

An uncertain and not just risky situation may be modeled using so-called belief functions assigning lower probabilities to subsets of outcomes. In this article we extend the von Neumann-Morgenstern expected utility theory from probability measures to belief functions. We use this theory to characterize uncertainty neutrality and different degrees of uncertainty aversion.

Hans JØrgen Jacobsen; Birgitte Sloth; TORBEN TRANAES

1994-01-01

3

Stability and Benefits of Suboptimal Utility Maximization  

Microsoft Academic Search

Abstract—Network utility maximization has been widely used to model,resource allocation and,network architectures. But in practice often it cannot be solved optimally due,to complexity reasons. Thus motivated, we address the following two questions in this paper: can suboptimal utility maximization maintain queue stability? Can under-optimization of utility objective function in fact lead to benefits to other network design objectives? We show

Tian Lan; Xiaojun Lin; Mung Chiang; Ruby B. Lee

2011-01-01

4

Blood detection in wireless capsule endoscopy using expectation maximization clustering  

NASA Astrophysics Data System (ADS)

Wireless Capsule Endoscopy (WCE) is a relatively new technology (FDA approved in 2002) allowing doctors to view most of the small intestine. Other endoscopies such as colonoscopy, upper gastrointestinal endoscopy, push enteroscopy, and intraoperative enteroscopy could be used to visualize up to the stomach, duodenum, colon, and terminal ileum, but there existed no method to view most of the small intestine without surgery. With the miniaturization of wireless and camera technologies came the ability to view the entire gestational track with little effort. A tiny disposable video capsule is swallowed, transmitting two images per second to a small data receiver worn by the patient on a belt. During an approximately 8-hour course, over 55,000 images are recorded to a worn device and then downloaded to a computer for later examination. Typically, a medical clinician spends more than two hours to analyze a WCE video. Research has been attempted to automatically find abnormal regions (especially bleeding) to reduce the time needed to analyze the videos. The manufacturers also provide the software tool to detect the bleeding called Suspected Blood Indicator (SBI), but its accuracy is not high enough to replace human examination. It was reported that the sensitivity and the specificity of SBI were about 72% and 85%, respectively. To address this problem, we propose a technique to detect the bleeding regions automatically utilizing the Expectation Maximization (EM) clustering algorithm. Our experimental results indicate that the proposed bleeding detection method achieves 92% and 98% of sensitivity and specificity, respectively.

Hwang, Sae; Oh, JungHwan; Cox, Jay; Tang, Shou Jiang; Tibbals, Harry F.

2006-03-01

5

Image fusion based on expectation maximization algorithm and steerable pyramid  

Microsoft Academic Search

In this paper, a novel image fusion method based on the expectation maximization (EM) algorithm and steerable pyramid is proposed. The registered images are first decomposed by using steerable pyramid. The EM algorithm is used to fuse the image components in the low frequency band. The selection method involving the informative importance measure is applied to those in the high

Gang Liu; Zhongliang Jing; Shaoyuan Sun; Jianxun Li; Zhenhua Li; Henry Leung

2004-01-01

6

Expected utility theory without the completeness axiom  

Microsoft Academic Search

We study the problem of obtaining an expected utility representation for a potentially incomplete preference relation over lotteries by means of a set of von Neumann–Morgenstern utility functions. It is shown that, when the prize space is a compact metric space, a preference relation admits such a multi-utility representation provided that it satisfies the standard axioms of expected utility theory.

Juan Dubra; Fabio Maccheroni; Efe A. Ok

2004-01-01

7

Image fusion based on expectation maximization algorithm and steerable pyramid  

NASA Astrophysics Data System (ADS)

In this paper, a novel image fusion method based on the expectation maximization (EM) algorithm and steerable pyramid is proposed. The registered images are first decomposed by using steerable pyramid. The EM algorithm is used to fuse the image components in the low frequency band. The selection method involving the informative importance measure is applied to those in the high frequency band. The final fused image is then computed by taking the inverse transform on the composite coefficient representations. Experimental results show that the proposed method outperforms conventional image fusion methods.

Liu, Gang; Jing, Zhongliang; Sun, Shaoyuan; Li, Jianxun; Li, Zhenhua; Leung, Henry

2004-07-01

8

Globally Optimal Distributed Power Control for Nonconcave Utility Maximization  

Microsoft Academic Search

Future wireless networks are expected to operate in dense environments where\\u000athe system capacity is fundamentally limited by severe co-channel interference\\u000aamong neighboring links. Transmit-power control has been recently explored as\\u000aan important interference-mitigation technique that aims to maximize a system\\u000aefficiency metric, which is often measured by a system utility function.\\u000aOptimal power control is known to be difficult

Li Ping Qian; Ying Jun Zhang; Mung Chiang

2010-01-01

9

Expected Utility Distributions for Flexible, Contingent Execution  

NASA Technical Reports Server (NTRS)

This paper presents a method for using expected utility distributions in the execution of flexible, contingent plans. A utility distribution maps the possible start times of an action to the expected utility of the plan suffix starting with that action. The contingent plan encodes a tree of possible courses of action and includes flexible temporal constraints and resource constraints. When execution reaches a branch point, the eligible option with the highest expected utility at that point in time is selected. The utility distributions make this selection sensitive to the runtime context, yet still efficient. Our approach uses predictions of action duration uncertainty as well as expectations of resource usage and availability to determine when an action can execute and with what probability. Execution windows and probabilities inevitably change as execution proceeds, but such changes do not invalidate the cached utility distributions, thus, dynamic updating of utility information is minimized.

Bresina, John L.; Washington, Richard

2000-01-01

10

An expectation maximization algorithm for training hidden substitution models.  

PubMed

We derive an expectation maximization algorithm for maximum-likelihood training of substitution rate matrices from multiple sequence alignments. The algorithm can be used to train hidden substitution models, where the structural context of a residue is treated as a hidden variable that can evolve over time. We used the algorithm to train hidden substitution matrices on protein alignments in the Pfam database. Measuring the accuracy of multiple alignment algorithms with reference to BAliBASE (a database of structural reference alignments) our substitution matrices consistently outperform the PAM series, with the improvement steadily increasing as up to four hidden site classes are added. We discuss several applications of this algorithm in bioinformatics. PMID:11955022

Holmes, I; Rubin, G M

2002-04-12

11

An Expectation-Maximization Method for Calibrating Synchronous Machine Models  

SciTech Connect

The accuracy of a power system dynamic model is essential to its secure and efficient operation. Lower confidence in model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, this paper proposes an expectation-maximization (EM) method to calibrate the synchronous machine model using phasor measurement unit (PMU) data. First, an extended Kalman filter (EKF) is applied to estimate the dynamic states using measurement data. Then, the parameters are calculated based on the estimated states using maximum likelihood estimation (MLE) method. The EM method iterates over the preceding two steps to improve estimation accuracy. The proposed EM method’s performance is evaluated using a single-machine infinite bus system and compared with a method where both state and parameters are estimated using an EKF method. Sensitivity studies of the parameter calibration using EM method are also presented to show the robustness of the proposed method for different levels of measurement noise and initial parameter uncertainty.

Meng, Da; Zhou, Ning; Lu, Shuai; Lin, Guang

2013-07-21

12

PEM-PCA: A Parallel Expectation-Maximization PCA Face Recognition Architecture.  

PubMed

Principal component analysis or PCA has been traditionally used as one of the feature extraction techniques in face recognition systems yielding high accuracy when requiring a small number of features. However, the covariance matrix and eigenvalue decomposition stages cause high computational complexity, especially for a large database. Thus, this research presents an alternative approach utilizing an Expectation-Maximization algorithm to reduce the determinant matrix manipulation resulting in the reduction of the stages' complexity. To improve the computational time, a novel parallel architecture was employed to utilize the benefits of parallelization of matrix computation during feature extraction and classification stages including parallel preprocessing, and their combinations, so-called a Parallel Expectation-Maximization PCA architecture. Comparing to a traditional PCA and its derivatives, the results indicate lower complexity with an insignificant difference in recognition precision leading to high speed face recognition systems, that is, the speed-up over nine and three times over PCA and Parallel PCA. PMID:24955405

Rujirakul, Kanokmon; So-In, Chakchai; Arnonkijpanich, Banchar

2014-01-01

13

PEM-PCA: A Parallel Expectation-Maximization PCA Face Recognition Architecture  

PubMed Central

Principal component analysis or PCA has been traditionally used as one of the feature extraction techniques in face recognition systems yielding high accuracy when requiring a small number of features. However, the covariance matrix and eigenvalue decomposition stages cause high computational complexity, especially for a large database. Thus, this research presents an alternative approach utilizing an Expectation-Maximization algorithm to reduce the determinant matrix manipulation resulting in the reduction of the stages' complexity. To improve the computational time, a novel parallel architecture was employed to utilize the benefits of parallelization of matrix computation during feature extraction and classification stages including parallel preprocessing, and their combinations, so-called a Parallel Expectation-Maximization PCA architecture. Comparing to a traditional PCA and its derivatives, the results indicate lower complexity with an insignificant difference in recognition precision leading to high speed face recognition systems, that is, the speed-up over nine and three times over PCA and Parallel PCA.

Rujirakul, Kanokmon; Arnonkijpanich, Banchar

2014-01-01

14

Expected utility expressed in terms of moments  

Microsoft Academic Search

Following a review of the problem of establishing a preference ordering over a set of distributions, the principles of Pascal, Bernoulli and Tetens are discussed. The second section of the paper outlines ways of expressing expected utility in terms of moments, thus combining the Bernoulli and Tetens principles. The paper concludes by suggesting that the Tetens principle contains some very

Karl Borch

1973-01-01

15

A modified expectation maximization algorithm for penalized likelihood estimation in emission tomography  

Microsoft Academic Search

The maximum likelihood (ML) expectation maximization (EM) approach in emission tomography has been very popular in medical imaging for several years. In spite of this, no satisfactory convergent modifications have been proposed for the regularized approach. Here, a modification of the EM algorithm is presented. The new method is a natural extension of the EM for maximizing likelihood with concave

Alvaro R. De Pierro

1995-01-01

16

Expectation Maximization and its Application in Modeling, Segmentation and Anomaly Detection.  

National Technical Information Service (NTIS)

Expectation Maximization (EM) is a general purpose algorithm for solving maximum likelihood estimation problems in a wide variety of situations best described as incomplete data problems. The incompleteness of the data may arise due to missing data, trunc...

R. Ganju

2008-01-01

17

AREM: Aligning Short Reads from ChIP-Sequencing by Expectation Maximization  

NASA Astrophysics Data System (ADS)

High-throughput sequencing coupled to chromatin immunoprecipitation (ChIP-Seq) is widely used in characterizing genome-wide binding patterns of transcription factors, cofactors, chromatin modifiers, and other DNA binding proteins. A key step in ChIP-Seq data analysis is to map short reads from high-throughput sequencing to a reference genome and identify peak regions enriched with short reads. Although several methods have been proposed for ChIP-Seq analysis, most existing methods only consider reads that can be uniquely placed in the reference genome, and therefore have low power for detecting peaks located within repeat sequences. Here we introduce a probabilistic approach for ChIP-Seq data analysis which utilizes all reads, providing a truly genome-wide view of binding patterns. Reads are modeled using a mixture model corresponding to K enriched regions and a null genomic background. We use maximum likelihood to estimate the locations of the enriched regions, and implement an expectation-maximization (E-M) algorithm, called AREM (aligning reads by expectation maximization), to update the alignment probabilities of each read to different genomic locations. We apply the algorithm to identify genome-wide binding events of two proteins: Rad21, a component of cohesin and a key factor involved in chromatid cohesion, and Srebp-1, a transcription factor important for lipid/cholesterol homeostasis. Using AREM, we were able to identify 19,935 Rad21 peaks and 1,748 Srebp-1 peaks in the mouse genome with high confidence, including 1,517 (7.6%) Rad21 peaks and 227 (13%) Srebp-1 peaks that were missed using only uniquely mapped reads. The open source implementation of our algorithm is available at http://sourceforge.net/projects/arem

Newkirk, Daniel; Biesinger, Jacob; Chon, Alvin; Yokomori, Kyoko; Xie, Xiaohui

18

An expected utility maximizer walks into a bar...  

PubMed Central

We conducted field experiments at a bar to test whether blood alcohol concentration (BAC) correlates with violations of the generalized axiom of revealed preference (GARP) and the independence axiom. We found that individuals with BACs well above the legal limit for driving adhere to GARP and independence at rates similar to those who are sober. This finding led to the fielding of a third experiment to explore how risk preferences might vary as a function of BAC. We found gender-specific effects: Men did not exhibit variations in risk preferences across BACs. In contrast, women were more risk averse than men at low BACs but exhibited increasing tolerance towards risks as BAC increased. Based on our estimates, men and women’s risk preferences are predicted to be identical at BACs nearly twice the legal limit for driving. We discuss the implications for policy-makers.

Glimcher, Paul W.; Lazzaro, Stephanie C.

2013-01-01

19

Distributed Network Utility Maximization using Event-triggered Barrier Methods  

Microsoft Academic Search

Abstract— Many problems associated with networked,sys- tems can be formulated as network utility maximization (NUM) problems. Dual decomposition is a widely used distributed al- gorithm that solves the NUM problem. This approach, however, uses a step size that is inversely proportional to measures of network size such as maximum,path length or maximum neighborhood size. As a result, the number of

Pu Wan; Michael D. Lemmon

20

Utility Maximization in Incomplete Markets with Random Endowment  

Microsoft Academic Search

This paper solves a long-standing open problem in mathematical nance: to nd a solution to the problem of maximizing utility from terminal wealth of an agent with a random endowment process, in the general, semimartingale model for incomplete markets, and to charac- terize it via the associated dual problem. We show that this is indeed possible if the dual problem

Walter Schachermayer; Hui Wang

2000-01-01

21

Planning Routes Across Economic Terrains: Maximizing Utility, Following Heuristics  

PubMed Central

We designed an economic task to investigate human planning of routes in landscapes where travel in different kinds of terrain incurs different costs. Participants moved their finger across a touch screen from a starting point to a destination. The screen was divided into distinct kinds of terrain and travel within each kind of terrain imposed a cost proportional to distance traveled. We varied costs and spatial configurations of terrains and participants received fixed bonuses minus the total cost of the routes they chose. We first compared performance to a model maximizing gain. All but one of 12 participants failed to adopt least-cost routes and their failure to do so reduced their winnings by about 30% (median value). We tested in detail whether participants’ choices of routes satisfied three necessary conditions (heuristics) for a route to maximize gain. We report failures of one heuristic for 7 out of 12 participants. Last of all, we modeled human performance with the assumption that participants assign subjective utilities to costs and maximize utility. For 7 out 12 participants, the fitted utility function was an accelerating power function of actual cost and for the remaining 5, a decelerating power function. We discuss connections between utility aggregation in route planning and decision under risk. Our task could be adapted to investigate human strategy and optimality of route planning in full-scale landscapes.

Zhang, Hang; Maddula, Soumya V.; Maloney, Laurence T.

2010-01-01

22

AHP for Risk Management Based on Expected Utility Theory  

NASA Astrophysics Data System (ADS)

This paper presents a model of decision-making considering the risk assessment. The conventional evaluation in AHP is considered to be a kind of utility. When dealing with the risk, however, it is necessary to consider the probability of damage. In order to take risk into decision-making problem, we construct AHP based on expected utility. The risk is considered as a related element of criterion rather than criterion itself. The expected utility is integrated, considering that satisfaction is positive utility and damage by risk is negative utility. Then, evaluation in AHP is executed using the expected utility.

Azuma, Rumiko; Miyagi, Hayao

23

The Japanese utilities` expectations for subchannel analysis  

SciTech Connect

Boiling water reactor (BWR) utilities in Japan began to consider the development of a mechanistic model to describe the critical heat transfer conditions in the BWR fuel subchannel. Such a mechanistic model will not only decrease the necessity of tests, but will also help by removing some overly conservative safety margins in thermal hydraulics. With the use of a postdryout heat transfer correlation, new acceptance criteria may be applicable to evaluate the fuel integrity. Mechanistic subchannel analysis models will certainly back up this approach. This model will also be applicable to the analysis of large-size fuel bundles and examination of corrosion behavior.

Toba, Akio; Omoto, Akira [Tokyo Electric Power Co. (Japan)

1995-12-01

24

Utility maximization in incomplete markets with random endowment  

Microsoft Academic Search

.   This paper solves the following problem of mathematical finance: to find a solution to the problem of maximizing utility\\u000a from terminal wealth of an agent with a random endowment process, in the general, semimartingale model for incomplete markets,\\u000a and to characterize it via the associated dual problem. We show that this is possible if the dual problem and its

Jakša Cvitani?; Walter Schachermayer; Hui Wang

2001-01-01

25

A classification of bioinformatics algorithms from the viewpoint of maximizing expected accuracy (MEA).  

PubMed

Many estimation problems in bioinformatics are formulated as point estimation problems in a high-dimensional discrete space. In general, it is difficult to design reliable estimators for this type of problem, because the number of possible solutions is immense, which leads to an extremely low probability for every solution-even for the one with the highest probability. Therefore, maximum score and maximum likelihood estimators do not work well in this situation although they are widely employed in a number of applications. Maximizing expected accuracy (MEA) estimation, in which accuracy measures of the target problem and the entire distribution of solutions are considered, is a more successful approach. In this review, we provide an extensive discussion of algorithms and software based on MEA. We describe how a number of algorithms used in previous studies can be classified from the viewpoint of MEA. We believe that this review will be useful not only for users wishing to utilize software to solve the estimation problems appearing in this article, but also for developers wishing to design algorithms on the basis of MEA. PMID:22313125

Hamada, Michiaki; Asai, Kiyoshi

2012-05-01

26

A Classification of Bioinformatics Algorithms from the Viewpoint of Maximizing Expected Accuracy (MEA)  

PubMed Central

Abstract Many estimation problems in bioinformatics are formulated as point estimation problems in a high-dimensional discrete space. In general, it is difficult to design reliable estimators for this type of problem, because the number of possible solutions is immense, which leads to an extremely low probability for every solution—even for the one with the highest probability. Therefore, maximum score and maximum likelihood estimators do not work well in this situation although they are widely employed in a number of applications. Maximizing expected accuracy (MEA) estimation, in which accuracy measures of the target problem and the entire distribution of solutions are considered, is a more successful approach. In this review, we provide an extensive discussion of algorithms and software based on MEA. We describe how a number of algorithms used in previous studies can be classified from the viewpoint of MEA. We believe that this review will be useful not only for users wishing to utilize software to solve the estimation problems appearing in this article, but also for developers wishing to design algorithms on the basis of MEA.

Asai, Kiyoshi

2012-01-01

27

Online Expectation Maximization based algorithms for inference in hidden Markov models  

Microsoft Academic Search

The Expectation Maximization (EM) algorithm is a versatile tool for model parameter estimation in latent data models. When processing large data sets or data stream however, EM becomes intractable since it requires the whole data set to be available at each iteration of the algorithm. In this contribution, a new generic online EM algorithm for model parameter inference in general

Sylvain Le Corff; Gersende Fort

2011-01-01

28

An expectation-maximization-based interacting multiple model approach for cooperative driving systems  

Microsoft Academic Search

In this paper, we present a novel combined sensor registration and fusion approach for cooperative driving in intelligent transportation systems (ITSs). A realistic augmented registration and fusion-state space model in three dimensions is first developed for dissimilar sensors. In order to have unbiased sensor registration parameter estimates, the expectation-maximization (EM) algorithm is incorporated with the extended Kalman filter (EKF) to

Dongliang Huang; Henry Leung

2005-01-01

29

Prediction of RNA secondary structure by maximizing pseudo-expected accuracy  

PubMed Central

Background Recent studies have revealed the importance of considering the entire distribution of possible secondary structures in RNA secondary structure predictions; therefore, a new type of estimator is proposed including the maximum expected accuracy (MEA) estimator. The MEA-based estimators have been designed to maximize the expected accuracy of the base-pairs and have achieved the highest level of accuracy. Those methods, however, do not give the single best prediction of the structure, but employ parameters to control the trade-off between the sensitivity and the positive predictive value (PPV). It is unclear what parameter value we should use, and even the well-trained default parameter value does not, in general, give the best result in popular accuracy measures to each RNA sequence. Results Instead of using the expected values of the popular accuracy measures for RNA secondary structure prediction, which is difficult to be calculated, the pseudo-expected accuracy, which can easily be computed from base-pairing probabilities, is introduced. It is shown that the pseudo-expected accuracy is a good approximation in terms of sensitivity, PPV, MCC, or F-score. The pseudo-expected accuracy can be approximately maximized for each RNA sequence by stochastic sampling. It is also shown that well-balanced secondary structures between sensitivity and PPV can be predicted with a small computational overhead by combining the pseudo-expected accuracy of MCC or F-score with the ?-centroid estimator. Conclusions This study gives not only a method for predicting the secondary structure that balances between sensitivity and PPV, but also a general method for approximately maximizing the (pseudo-)expected accuracy with respect to various evaluation measures including MCC and F-score.

2010-01-01

30

Disconfirmation of Expectations of Utility in e-Learning  

ERIC Educational Resources Information Center

Using pre-training and post-training paired surveys in e-learning based training courses, we have compared the "expectations of utility," measured at the beginning of an e-learning course, with the "perceptions of utility," measured at the end of the course, and related it with the trainees' motivation. We have concluded…

Cacao, Rosario

2013-01-01

31

Spatially aware expectation maximization (SpAEM): application to prostate TRUS segmentation  

NASA Astrophysics Data System (ADS)

In this paper we introduce Spatially Aware Expectation Maximization (SpAEM), a new parameter estimation method which incorporates information pertaining to spatial prior probability into the traditional expectation- maximization framework. For estimating the parameters of a given class, the spatial prior probability allows us to weight the contribution of any pixel based on the probability of that pixel belonging to the class of interest. In this paper we evaluate SpAEM for the problem of prostate capsule segmentation in transrectal ultrasound (TRUS) images. In cohort of 6 patients, SpAEM qualitatively and quantitatively outperforms traditional EM in distinguishing the foreground (prostate) from background (non-prostate) regions by around 45% in terms of the Sorensen Dice overlap measure, when compared against expert annotations. The variance of the estimated parameters measured via Cramer-Rao Lower Bound suggests that SpAEM yields unbiased estimates. Finally, on a synthetic TRUS image, the Cramer-Von Mises (CVM) criteria shows that SpAEM improves the estimation accuracy by around 51% and 88% for prostate and background, respectively, as compared to traditional EM.

Orooji, Mahdi; Sparks, Rachel; Bloch, B. Nicolas; Feleppa, Ernest; Barratt, Dean; Madabhushi, Anant

2014-03-01

32

Implementation and evaluation of an expectation maximization reconstruction algorithm for gamma emission breast tomosynthesis  

PubMed Central

Purpose: We are developing a dual modality tomosynthesis breast scanner in which x-ray transmission tomosynthesis and gamma emission tomosynthesis are performed sequentially with the breast in a common configuration. In both modalities projection data are obtained over an angular range of less than 180° from one side of the mildly compressed breast resulting in incomplete and asymmetrical sampling. The objective of this work is to implement and evaluate a maximum likelihood expectation maximization (MLEM) reconstruction algorithm for gamma emission breast tomosynthesis (GEBT). Methods: A combination of Monte Carlo simulations and phantom experiments was used to test the MLEM algorithm for GEBT. The algorithm utilizes prior information obtained from the x-ray breast tomosynthesis scan to partially compensate for the incomplete angular sampling and to perform attenuation correction (AC) and resolution recovery (RR). System spatial resolution, image artifacts, lesion contrast, and signal to noise ratio (SNR) were measured as image quality figures of merit. To test the robustness of the reconstruction algorithm and to assess the relative impacts of correction techniques with changing angular range, simulations and experiments were both performed using acquisition angular ranges of 45°, 90° and 135°. For comparison, a single projection containing the same total number of counts as the full GEBT scan was also obtained to simulate planar breast scintigraphy. Results: The in-plane spatial resolution of the reconstructed GEBT images is independent of source position within the reconstructed volume and independent of acquisition angular range. For 45° acquisitions, spatial resolution in the depth dimension (the direction of breast compression) is degraded with increasing source depth (increasing distance from the collimator surface). Increasing the acquisition angular range from 45° to 135° both greatly reduces this depth dependence and improves the average depth dimension resolution from 10.8 to 4.8 mm. The 135° acquisition results in a near-isotropic, spatially uniform 3D resolution of approximately 4.3 mm full width at half maximum. Background nonuniformity (cupping) artifacts arise primarily from angular incompleteness for small angular range acquisition but primarily from gamma ray attenuation at larger angular range. However, background artifacts can be largely eliminated if both prior information regularization and AC are applied. An artificial decrease in lesion voxel value with increasing lesion depth can also be substantially reduced through a combination of AC and RR. In experiments using compressible gelatin breast phantoms, lesion contrast and SNR are about 2.6–8.8 times and 2.3–5.6 times higher, respectively, in GEBT than in planar breast scintigraphy depending on the acquisition angle, the gamma camera trajectory, and the lesion location. In addition, the strong reduction in lesion contrast and SNR with increasing lesion depth that is observed in planar breast scintigraphy can be largely overcome in GEBT. Conclusions: The authors have demonstrated a promising EM-based reconstruction scheme for use in GEBT. Compared to planar breast scintigraphy GEBT provides superior and less position-dependent lesion contrast, lesion SNR, and spatial resolution as well as more accurate quantification of lesion-to-background activity concentration ratio.

Gong, Zongyi; Klanian, Kelly; Patel, Tushita; Sullivan, Olivia; Williams, Mark B.

2012-01-01

33

Investigating Generalizations of Expected Utility Theory Using Experimental Data  

Microsoft Academic Search

A number of generalizations of the expected utility preference functional are estimated using experimentally generated data involving 100 pairwise choice questions repeated on two separate occasions. Likelihood ratio tests are conducted to investigate the statistical superiority of the various generalizations and the Akaike information criterion is used to distinguish between them. The economic superiority of the various generalizations is also

John D. Hey; Chris Orme

1994-01-01

34

Comparison of two robust estimations by expectation maximization algorithms with Huber's method and outlier tests  

NASA Astrophysics Data System (ADS)

The robust estimation by the expectation maximization (EM) algorithm is derived for the variance-inflation model in addition to the known estimation for the mean-shift model. To compare these methods with the ? - test, Huber's robust M-estimation and the multiple outlier test, a random linear model and laser scans for fitting a plane are generated by Monte Carlo methods. It turns out that the results for detecting outliers by the EM algorithms for the mean-shift and variance-inflation model approximately agree although the numbers of convergences are different. The results are superior to the ones of the methods with which they are compared. In case of the generated laser scans, the maximum number of outliers, which can be detected, is approximately identified.

Koch, Karl-Rudolf

2013-05-01

35

String-averaging expectation-maximization for maximum likelihood estimation in emission tomography  

NASA Astrophysics Data System (ADS)

We study the maximum likelihood model in emission tomography and propose a new family of algorithms for its solution, called string-averaging expectation-maximization (SAEM). In the string-averaging algorithmic regime, the index set of all underlying equations is split into subsets, called ‘strings’, and the algorithm separately proceeds along each string, possibly in parallel. Then, the end-points of all strings are averaged to form the next iterate. SAEM algorithms with several strings present better practical merits than the classical row-action maximum-likelihood algorithm. We present numerical experiments showing the effectiveness of the algorithmic scheme, using data of image reconstruction problems. Performance is evaluated from the computational cost and reconstruction quality viewpoints. A complete convergence theory is also provided.

Salomão Helou, Elias; Censor, Yair; Chen, Tai-Been; Chern, I.-Liang; Rodolfo De Pierro, Álvaro; Jiang, Ming; Horng-Shing Lu, Henry

2014-05-01

36

Simultaneously learning DNA motif along with its position and sequence rank preferences through expectation maximization algorithm.  

PubMed

Although de novo motifs can be discovered through mining over-represented sequence patterns, this approach misses some real motifs and generates many false positives. To improve accuracy, one solution is to consider some additional binding features (i.e., position preference and sequence rank preference). This information is usually required from the user. This article presents a de novo motif discovery algorithm called SEME (sampling with expectation maximization for motif elicitation), which uses pure probabilistic mixture model to model the motif's binding features and uses expectation maximization (EM) algorithms to simultaneously learn the sequence motif, position, and sequence rank preferences without asking for any prior knowledge from the user. SEME is both efficient and accurate thanks to two important techniques: the variable motif length extension and importance sampling. Using 75 large-scale synthetic datasets, 32 metazoan compendium benchmark datasets, and 164 chromatin immunoprecipitation sequencing (ChIP-Seq) libraries, we demonstrated the superior performance of SEME over existing programs in finding transcription factor (TF) binding sites. SEME is further applied to a more difficult problem of finding the co-regulated TF (coTF) motifs in 15 ChIP-Seq libraries. It identified significantly more correct coTF motifs and, at the same time, predicted coTF motifs with better matching to the known motifs. Finally, we show that the learned position and sequence rank preferences of each coTF reveals potential interaction mechanisms between the primary TF and the coTF within these sites. Some of these findings were further validated by the ChIP-Seq experiments of the coTFs. The application is available online. PMID:23461573

Zhang, ZhiZhuo; Chang, Cheng Wei; Hugo, Willy; Cheung, Edwin; Sung, Wing-Kin

2013-03-01

37

Robust estimations for the nonlinear Gauss Helmert model by the expectation maximization algorithm  

NASA Astrophysics Data System (ADS)

For deriving the robust estimation by the EM (expectation maximization) algorithm for a model, which is more general than the linear model, the nonlinear Gauss Helmert (GH) model is chosen. It contains the errors-in-variables model as a special case. The nonlinear GH model is difficult to handle because of the linearization and the Gauss Newton iterations. Approximate values for the observations have to be introduced for the linearization. Robust estimates by the EM algorithm based on the variance-inflation model and the mean-shift model have been derived for the linear model in case of homoscedasticity. To derive these two EM algorithms for the GH model, different variances are introduced for the observations and the expectations of the measurements defined by the linear model are replaced by the ones of the GH model. The two robust methods are applied to fit by the GH model a polynomial surface of second degree to the measured three-dimensional coordinates of a laser scanner. This results in detecting more outliers than by the linear model.

Koch, Karl-Rudolf

2014-03-01

38

AUSI expected utility: An anticipated utility theory of relative disappointment aversion  

Microsoft Academic Search

In this paper we provide an axiomatization for a representation of preferences over lotteries that is only one parameter richer than expected utility. Our model is a special case of Rank-Dependent Expected Utility. Moreover, we show that the same restriction on this parameter is required for: risk aversion; intuitive comparative static results for a reasonably general class of economically interesting

Simon Grant; Atsushi Kajii

1998-01-01

39

A simple test of expected utility theory using professional traders.  

PubMed

We compare behavior across students and professional traders from the Chicago Board of Trade in a classic Allais paradox experiment. Our experiment tests whether independence, a necessary condition in expected utility theory, is systematically violated. We find that both students and professionals exhibit some behavior consistent with the Allais paradox, but the data pattern does suggest that the trader population falls prey to the Allais paradox less frequently than the student population. PMID:15634739

List, John A; Haigh, Michael S

2005-01-18

40

An Expectation Maximization based Method for Subcellular Particle Tracking using Multi-angle TIRF Microscopy*  

PubMed Central

Multi-angle total internal reflection fluorescence microscopy (MA-TIRFM) is a new generation of TIRF microscopy to study cellular processes near dorsal cell membrane in 4 dimensions (3D+t). To perform quantitative analysis using MA-TIRFM, it is necessary to track subcellular particles in these processes. In this paper, we propose a method based on a MAP framework for automatic particle tracking and apply it to track clathrin coated pits (CCPs). The expectation maximization (EM) algorithm is employed to solve the MAP problem. To provide the initial estimations for the EM algorithm, we develop a forward filter based on the most probable trajectory (MPT) filter. Multiple linear models are used to model particle dynamics. For CCP tracking, we use two linear models to describe constrained Brownian motion and fluorophore variation according to CCP properties. The tracking method is evaluated on synthetic data and results show that it has high accuracy. The result on real data confirmed by human expert cell biologists is also presented.

Liang, Liang; Shen, Hongying; De Camilli, Pietro; Toomre, Derek K.; Duncan, James S.

2013-01-01

41

Image segmentation with implicit color standardization using spatially constrained expectation maximization: detection of nuclei.  

PubMed

Color nonstandardness--the propensity for similar objects to exhibit different color properties across images--poses a significant problem in the computerized analysis of histopathology. Though many papers propose means for improving color constancy, the vast majority assume image formation via reflective light instead of light transmission as in microscopy, and thus are inappropriate for histological analysis. Previously, we presented a novel Bayesian color segmentation algorithm for histological images that is highly robust to color nonstandardness; this algorithm employed the expectation maximization (EM) algorithm to dynamically estimate for each individual image the probability density functions that describe the colors of salient objects. However, our approach, like most EM-based algorithms, ignored important spatial constraints, such as those modeled by Markov random field (MRFs). Addressing this deficiency, we now present spatially-constrained EM (SCEM), a novel approach for incorporating Markov priors into the EM framework. With respect to our segmentation system, we replace EM with SCEM and then assess its improved ability to segment nuclei in H&E stained histopathology. Segmentation performance is evaluated over seven (nearly) identical sections of gastrointestinal tissue stained using different protocols (simulating severe color nonstandardness). Over this dataset, our system identifies nuclear regions with an area under the receiver operator characteristic curve (AUC) of 0.838. If we disregard spatial constraints, the AUC drops to 0.748. PMID:23285572

Monaco, James; Hipp, J; Lucas, D; Smith, S; Balis, U; Madabhushi, Anant

2012-01-01

42

An homomorphic filtering and expectation maximization approach for the point spread function estimation in ultrasound imaging  

NASA Astrophysics Data System (ADS)

In modern ultrasound imaging systems, the spatial resolution is severely limited due to the effects of both the finite aperture and overall bandwidth of ultrasound transducers and the non-negligible width of the transmitted ultrasound beams. This low spatial resolution remains the major limiting factor in the clinical usefulness of medical ultrasound images. In order to recover clinically important image details, which are often masked due to this resolution limitation, an image restoration procedure should be applied. To this end, an estimation of the Point Spread Function (PSF) of the ultrasound imaging system is required. This paper introduces a novel, original, reliable, and fast Maximum Likelihood (ML) approach for recovering the PSF of an ultrasound imaging system. This new PSF estimation method assumes as a constraint that the PSF is of known parametric form. Under this constraint, the parameter values of its associated Modulation Transfer Function (MTF) are then efficiently estimated using a homomorphic filter, a denoising step, and an expectation-maximization (EM) based clustering algorithm. Given this PSF estimate, a deconvolution can then be efficiently used in order to improve the spatial resolution of an ultrasound image and to obtain an estimate (independent of the properties of the imaging system) of the true tissue reflectivity function. The experiments reported in this paper demonstrate the efficiency and illustrate all the potential of this new estimation and blind deconvolution approach.

Benameur, S.; Mignotte, M.; Lavoie, F.

2012-02-01

43

An expectation maximization reconstruction algorithm for emission tomography with non-uniform entropy prior.  

PubMed

A Bayesian image reconstruction algorithm is proposed for emission tomography. It incorporates the Poisson nature of the noise in the projection data and uses a non-uniform entropy as an a priori probability distribution of the image in a maximum a posteriori (MAP) approach. The expectation maximization (EM) method was applied to find the MAP estimator. The Newton-Raphson numerical method whose convergence and positive solutions are proven, was used to solve the EM problem. The prior mean at iteration k was determined by smoothing the image obtained at iteration k-1. Comparisons between the ML and the MAP algorithm were carried out with a numerical phantom that contains a narrow valley region. The ML solution after 50 iterations was chosen as the initial solution for the MAP algorithm, since the global performance of the ML algorithm deteriorates with increasing number of iterations while its local performance in the valley region is always improving. The resulting algorithm is a compromise between ML who has the best local performance in the valley region and the MAP who has the best global performance. PMID:7490164

Noumeir, R; Mailloux, G E; Lemieux, R

1995-06-01

44

An expectation and maximization algorithm for estimating Q X E interaction effects.  

PubMed

A Markov chain Monte Carlo (MCMC) implemented Bayesian method has been developed to detect quantitative trait loci (QTL) effects and Q x E interaction effects. However, the MCMC algorithm is time consuming due to repeated samplings of QTL parameters. We developed an expectation and maximization (EM) algorithm as an alternative method for detecting QTL and Q x E interaction. Simulation studies and real data analysis showed that the EM algorithm produced comparable result as the Bayesian method, but with a speed many magnitudes faster than the MCMC algorithm. We used the EM algorithm to analyze a well known barley dataset produced by the North American Barley Genome Mapping Project. The dataset contained eight quantitative traits collected from 150 doubled-haploid (DH) lines evaluated in multiple environments. Each line was genotyped for 495 polymorphic markers. The result showed that all eight traits exhibited QTL main effects and Q x E interaction effects. On average, the main effects and Q x E interaction effects contributed 34.56 and 16.23% of the total phenotypic variance, respectively. Furthermore, we found that whether or not a locus shows Q x E interaction does not depend on the presence of main effect. PMID:22297562

Zhao, Fuping; Xu, Shizhong

2012-05-01

45

Nonlinear impairment compensation using expectation maximization for dispersion managed and unmanaged PDM 16-QAM transmission.  

PubMed

In this paper, we show numerically and experimentally that expectation maximization (EM) algorithm is a powerful tool in combating system impairments such as fibre nonlinearities, inphase and quadrature (I/Q) modulator imperfections and laser linewidth. The EM algorithm is an iterative algorithm that can be used to compensate for the impairments which have an imprint on a signal constellation, i.e. rotation and distortion of the constellation points. The EM is especially effective for combating non-linear phase noise (NLPN). It is because NLPN severely distorts the signal constellation and this can be tracked by the EM. The gain in the nonlinear system tolerance for the system under consideration is shown to be dependent on the transmission scenario. We show experimentally that for a dispersion managed polarization multiplexed 16-QAM system at 14 Gbaud a gain in the nonlinear system tolerance of up to 3 dB can be obtained. For, a dispersion unmanaged system this gain reduces to 0.5 dB. PMID:23262850

Zibar, Darko; Winther, Ole; Franceschi, Niccolo; Borkowski, Robert; Caballero, Antonio; Arlunno, Valeria; Schmidt, Mikkel N; Gonzales, Neil Guerrero; Mao, Bangning; Ye, Yabin; Larsen, Knud J; Monroy, Idelfonso Tafur

2012-12-10

46

Modelling Transcriptional Regulation with a Mixture of Factor Analyzers and Variational Bayesian Expectation Maximization  

PubMed Central

Understanding the mechanisms of gene transcriptional regulation through analysis of high-throughput postgenomic data is one of the central problems of computational systems biology. Various approaches have been proposed, but most of them fail to address at least one of the following objectives: (1) allow for the fact that transcription factors are potentially subject to posttranscriptional regulation; (2) allow for the fact that transcription factors cooperate as a functional complex in regulating gene expression, and (3) provide a model and a learning algorithm with manageable computational complexity. The objective of the present study is to propose and test a method that addresses these three issues. The model we employ is a mixture of factor analyzers, in which the latent variables correspond to different transcription factors, grouped into complexes or modules. We pursue inference in a Bayesian framework, using the Variational Bayesian Expectation Maximization (VBEM) algorithm for approximate inference of the posterior distributions of the model parameters, and estimation of a lower bound on the marginal likelihood for model selection. We have evaluated the performance of the proposed method on three criteria: activity profile reconstruction, gene clustering, and network inference.

2009-01-01

47

Kernel and stochastic expectation maximization fusion for target detection in hyperspectral imagery  

NASA Astrophysics Data System (ADS)

In this paper, we present a new algorithm for target detection using hyperspectral imagery. The proposed algorithm is inspired by the outstanding performance of nonlinear RX-algorithm and the robustness of the stochastic expectation maximization (SEM) algorithm. The traditional technique of using SEM algorithm for target detection in hyperspectral imagery is associated with dimensionality reduction of the input data using binning or principal components analysis (PCA) algorithm. Although, the data reduction of the input data is enforced to reduce the computational burden on SEM algorithm, but it affects the results of target detection, especially the challenging one, due to not using the entire information of the potential targets. To facilitate detection of the target by using the entire targets information and simultaneously reducing the computational burden on SEM algorithm, we propose a new scheme for data reduction based on using Kernels. Kernel-based input data reduction is a nonlinear filtering technique in which the input data are mapped to the feature space where most of the background data is filtered using an easily selected threshold. Then, Gaussian mixture model is generated for the reduced input-data and SEM algorithm is employed to estimate the model parameters and to classify that input data. Finally, we allocated the target's class and isolated the target pixels. The proposed scheme for fusion the kernel with SEM algorithm has been tested using real life hyperspectral imagery and the results show superior performance compared to alternate algorithms.

Elbakary, M. I.; Alam, M. S.

2011-04-01

48

A Local Scalable Distributed Expectation Maximization Algorithm for Large Peer-to-Peer Networks  

NASA Technical Reports Server (NTRS)

This paper offers a local distributed algorithm for expectation maximization in large peer-to-peer environments. The algorithm can be used for a variety of well-known data mining tasks in a distributed environment such as clustering, anomaly detection, target tracking to name a few. This technology is crucial for many emerging peer-to-peer applications for bioinformatics, astronomy, social networking, sensor networks and web mining. Centralizing all or some of the data for building global models is impractical in such peer-to-peer environments because of the large number of data sources, the asynchronous nature of the peer-to-peer networks, and dynamic nature of the data/network. The distributed algorithm we have developed in this paper is provably-correct i.e. it converges to the same result compared to a similar centralized algorithm and can automatically adapt to changes to the data and the network. We show that the communication overhead of the algorithm is very low due to its local nature. This monitoring algorithm is then used as a feedback loop to sample data from the network and rebuild the model when it is outdated. We present thorough experimental results to verify our theoretical claims.

Bhaduri, Kanishka; Srivastava, Ashok N.

2009-01-01

49

Expected utility violations evolve under status-based selection mechanisms.  

PubMed

The expected utility theory of decision making under uncertainty, a cornerstone of modern economics, assumes that humans linearly weight "utilities" for different possible outcomes by the probabilities with which these outcomes occur. Despite the theory's intuitive appeal, both from normative and from evolutionary perspectives, many experiments demonstrate systematic, though poorly understood, patterns of deviation from EU predictions. This paper offers a novel theoretical account of such patterns of deviation by demonstrating that EU violations can emerge from evolutionary selection when individual "status" affects inclusive fitness. In humans, battles for resources and social standing involve high-stakes decision making, and assortative mating ensures that status matters for fitness outcomes. The paper therefore proposes grounding the study of decision making under uncertainty in an evolutionary game-theoretic framework. PMID:18656491

Dickson, Eric S

2008-10-01

50

Expecting the unexpected: applying the Develop-Distort Dilemma to maximize positive market impacts in health.  

PubMed

Although health interventions start with good intentions to develop services for disadvantaged populations, they often distort the health market, making the delivery or financing of services difficult once the intervention is over: a condition called the 'Develop-Distort Dilemma' (DDD). In this paper, we describe how to examine whether a proposed intervention may develop or distort the health market. Our goal is to produce a tool that facilitates meaningful and systematic dialogue for practitioners and researchers to ensure that well-intentioned health interventions lead to productive health systems while reducing the undesirable distortions of such efforts. We apply the DDD tool to plan for development rather than distortions in health markets, using intervention research being conducted under the Future Health Systems consortium in Bangladesh, China and Uganda. Through a review of research proposals and interviews with principal investigators, we use the DDD tool to systematically understand how a project fits within the broader health market system, and to identify gaps in planning for sustainability. We found that while current stakeholders and funding sources for activities were easily identified, future ones were not. The implication is that the projects could raise community expectations that future services will be available and paid for, despite this actually being uncertain. Each project addressed the 'rules' of the health market system differently. The China research assesses changes in the formal financing rules, whereas Bangladesh and Uganda's projects involve influencing community level providers, where informal rules are more important. In each case, we recognize the importance of building trust between providers, communities and government officials. Each project could both develop and distort local health markets. Anyone intervening in the health market must recognize the main market perturbations, whether positive or negative, and manage them so as to maximize the benefits to the health system and population health. PMID:23014153

Peters, David H; Paina, Ligia; Bennett, Sara

2012-10-01

51

Stochastic Dominance Implies the Equality (Choquet-Expected Utility = Anticipated Utility).  

National Technical Information Service (NTIS)

The aim of the paper is to convince the reader that Choquet-expected utility, as initiated by Schmeidler for decision making under uncertainty, when formulated for decision making under risk naturally leads to Yaari's anticipated utility. Thus the two gen...

P. Wakker

1989-01-01

52

Dynamic Bayesian Network (DBN) with Structure Expectation Maximization (SEM) for Modeling of Gene Network from Time Series Gene Expression Data  

Microsoft Academic Search

Exploring gene regulatory network is a key topic in molecular biology. In this paper, we present a new dynamic Bayesian network (DBN) framework embedded with structural expectation maximization (SEM) to model gene relationship. It is well-suited for analyzing the time-series data and can deal with cyclical structures that can not be tackled by static Bayesian network. We applied the new

Yu Zhang; Zhingdong Deng; Hongshan Jiang; Peifa Jia

2006-01-01

53

Recursive expectation-maximization (EM) algorithms for time-varying parameters with applications to multiple target tracking  

Microsoft Academic Search

We investigate the application of expectation maximization (EM) algorithms to the classical problem of multiple target tracking (MTT) for a known number of targets. Conventional algorithms, which deal with this problem, have a computational complexity that depends exponentially on the number of targets, and usually divide the problem into a localization stage and a tracking stage. The new algorithms achieve

Liron Frenkel; Meir Feder

1999-01-01

54

Geometric derivation of expectation-maximization and generalized successive interference cancellation algorithms with applications to CDMA channel estimation  

Microsoft Academic Search

The expectation-maximization (EM) algorithm is well established as a computationally efficient method for separable signal parameter estimation. Here, a new geometric derivation and interpretation of the EM algorithm is given that facilitates the understanding of EM convergence properties. Geometric considerations lead to an alternative separable signal parameter estimator based on successive cancellation. The new generalized successive interference cancellation (GSIC) algorithm

Ronald A. Iltis; Sunwoo Kim

2003-01-01

55

An event-triggered distributed primal-dual algorithm for Network Utility maximization  

Microsoft Academic Search

Many problems associated with networked sys- tems can be formulated as network utility maximization (NUM) problems. NUM problems maximize a global separable measure of network optimality subject to linear constraints on resources. Dual decomposition is a widely used distributed algorithm that solves the NUM problem. This approach, however, uses a step size that is inversely proportional to measures of network

Pu Wan; Michael D. Lemmon

2009-01-01

56

Recursive expectation-maximization clustering: A method for identifying buffering mechanisms composed of phenomic modules  

NASA Astrophysics Data System (ADS)

Interactions between genetic and/or environmental factors are ubiquitous, affecting the phenotypes of organisms in complex ways. Knowledge about such interactions is becoming rate-limiting for our understanding of human disease and other biological phenomena. Phenomics refers to the integrative analysis of how all genes contribute to phenotype variation, entailing genome and organism level information. A systems biology view of gene interactions is critical for phenomics. Unfortunately the problem is intractable in humans; however, it can be addressed in simpler genetic model systems. Our research group has focused on the concept of genetic buffering of phenotypic variation, in studies employing the single-cell eukaryotic organism, S. cerevisiae. We have developed a methodology, quantitative high throughput cellular phenotyping (Q-HTCP), for high-resolution measurements of gene-gene and gene-environment interactions on a genome-wide scale. Q-HTCP is being applied to the complete set of S. cerevisiae gene deletion strains, a unique resource for systematically mapping gene interactions. Genetic buffering is the idea that comprehensive and quantitative knowledge about how genes interact with respect to phenotypes will lead to an appreciation of how genes and pathways are functionally connected at a systems level to maintain homeostasis. However, extracting biologically useful information from Q-HTCP data is challenging, due to the multidimensional and nonlinear nature of gene interactions, together with a relative lack of prior biological information. Here we describe a new approach for mining quantitative genetic interaction data called recursive expectation-maximization clustering (REMc). We developed REMc to help discover phenomic modules, defined as sets of genes with similar patterns of interaction across a series of genetic or environmental perturbations. Such modules are reflective of buffering mechanisms, i.e., genes that play a related role in the maintenance of physiological homeostasis. To develop the method, 297 gene deletion strains were selected based on gene-drug interactions with hydroxyurea, an inhibitor of ribonucleotide reductase enzyme activity, which is critical for DNA synthesis. To partition the gene functions, these 297 deletion strains were challenged with growth inhibitory drugs known to target different genes and cellular pathways. Q-HTCP-derived growth curves were used to quantify all gene interactions, and the data were used to test the performance of REMc. Fundamental advantages of REMc include objective assessment of total number of clusters and assignment to each cluster a log-likelihood value, which can be considered an indicator of statistical quality of clusters. To assess the biological quality of clusters, we developed a method called gene ontology information divergence z-score (GOid_z). GOid_z summarizes total enrichment of GO attributes within individual clusters. Using these and other criteria, we compared the performance of REMc to hierarchical and K-means clustering. The main conclusion is that REMc provides distinct efficiencies for mining Q-HTCP data. It facilitates identification of phenomic modules, which contribute to buffering mechanisms that underlie cellular homeostasis and the regulation of phenotypic expression.

Guo, Jingyu; Tian, Dehua; McKinney, Brett A.; Hartman, John L.

2010-06-01

57

Recursive expectation-maximization clustering: A method for identifying buffering mechanisms composed of phenomic modules  

PubMed Central

Interactions between genetic and?or environmental factors are ubiquitous, affecting the phenotypes of organisms in complex ways. Knowledge about such interactions is becoming rate-limiting for our understanding of human disease and other biological phenomena. Phenomics refers to the integrative analysis of how all genes contribute to phenotype variation, entailing genome and organism level information. A systems biology view of gene interactions is critical for phenomics. Unfortunately the problem is intractable in humans; however, it can be addressed in simpler genetic model systems. Our research group has focused on the concept of genetic buffering of phenotypic variation, in studies employing the single-cell eukaryotic organism, S. cerevisiae. We have developed a methodology, quantitative high throughput cellular phenotyping (Q-HTCP), for high-resolution measurements of gene-gene and gene-environment interactions on a genome-wide scale. Q-HTCP is being applied to the complete set of S. cerevisiae gene deletion strains, a unique resource for systematically mapping gene interactions. Genetic buffering is the idea that comprehensive and quantitative knowledge about how genes interact with respect to phenotypes will lead to an appreciation of how genes and pathways are functionally connected at a systems level to maintain homeostasis. However, extracting biologically useful information from Q-HTCP data is challenging, due to the multidimensional and nonlinear nature of gene interactions, together with a relative lack of prior biological information. Here we describe a new approach for mining quantitative genetic interaction data called recursive expectation-maximization clustering (REMc). We developed REMc to help discover phenomic modules, defined as sets of genes with similar patterns of interaction across a series of genetic or environmental perturbations. Such modules are reflective of buffering mechanisms, i.e., genes that play a related role in the maintenance of physiological homeostasis. To develop the method, 297 gene deletion strains were selected based on gene-drug interactions with hydroxyurea, an inhibitor of ribonucleotide reductase enzyme activity, which is critical for DNA synthesis. To partition the gene functions, these 297 deletion strains were challenged with growth inhibitory drugs known to target different genes and cellular pathways. Q-HTCP-derived growth curves were used to quantify all gene interactions, and the data were used to test the performance of REMc. Fundamental advantages of REMc include objective assessment of total number of clusters and assignment to each cluster a log-likelihood value, which can be considered an indicator of statistical quality of clusters. To assess the biological quality of clusters, we developed a method called gene ontology information divergence z-score (GOid_z). GOid_z summarizes total enrichment of GO attributes within individual clusters. Using these and other criteria, we compared the performance of REMc to hierarchical and K-means clustering. The main conclusion is that REMc provides distinct efficiencies for mining Q-HTCP data. It facilitates identification of phenomic modules, which contribute to buffering mechanisms that underlie cellular homeostasis and the regulation of phenotypic expression.

Guo, Jingyu; Tian, Dehua; McKinney, Brett A.; Hartman, John L.

2010-01-01

58

Bandwidth utilization maximization of scientific RF communication systems  

SciTech Connect

A method for more efficiently utilizing the frequency bandwidth allocated for data transmission is presented. Current space and range communication systems use modulation and coding schemes that transmit 0.5 to 1.0 bits per second per Hertz of radio frequency bandwidth. The goal in this LDRD project is to increase the bandwidth utilization by employing advanced digital communications techniques. This is done with little or no increase in the transmit power which is usually very limited on airborne systems. Teaming with New Mexico State University, an implementation of trellis coded modulation (TCM), a coding and modulation scheme pioneered by Ungerboeck, was developed for this application and simulated on a computer. TCM provides a means for reliably transmitting data while simultaneously increasing bandwidth efficiency. The penalty is increased receiver complexity. In particular, the trellis decoder requires high-speed, application-specific digital signal processing (DSP) chips. A system solution based on the QualComm Viterbi decoder and the Graychip DSP receiver chips is presented.

Rey, D. [Sandia National Lab., Albuquerque, NM (United States); Ryan, W. [New Mexico State Univ., Las Cruces, NM (United States); Ross, M.

1997-01-01

59

Computational rationality: linking mechanism and behavior through bounded utility maximization.  

PubMed

We propose a framework for including information-processing bounds in rational analyses. It is an application of bounded optimality (Russell & Subramanian, 1995) to the challenges of developing theories of mechanism and behavior. The framework is based on the idea that behaviors are generated by cognitive mechanisms that are adapted to the structure of not only the environment but also the mind and brain itself. We call the framework computational rationality to emphasize the incorporation of computational mechanism into the definition of rational action. Theories are specified as optimal program problems, defined by an adaptation environment, a bounded machine, and a utility function. Such theories yield different classes of explanation, depending on the extent to which they emphasize adaptation to bounds, and adaptation to some ecology that differs from the immediate local environment. We illustrate this variation with examples from three domains: visual attention in a linguistic task, manual response ordering, and reasoning. We explore the relation of this framework to existing "levels" approaches to explanation, and to other optimality-based modeling approaches. PMID:24648415

Lewis, Richard L; Howes, Andrew; Singh, Satinder

2014-04-01

60

A Local Scalable Distributed Expectation Maximization Algorithm for Large Peer-to-Peer Networks  

Microsoft Academic Search

This paper offers a local distributed algorithm for expecta- tion maximization in large peer-to-peer environments. The algorithm can be used for a variety of well-known data min- ing tasks in a distributed environment such as clustering, anomaly detection, target tracking to name a few. This technology is crucial for many emerging peer-to-peer ap- plications for bioinformatics, astronomy, social networking, sensor

Kanishka Bhaduri; Ashok N. Srivastava

2009-01-01

61

Very Slow Search and Reach: Failure to Maximize Expected Gain in an Eye-Hand Coordination Task  

PubMed Central

We examined an eye-hand coordination task where optimal visual search and hand movement strategies were inter-related. Observers were asked to find and touch a target among five distractors on a touch screen. Their reward for touching the target was reduced by an amount proportional to how long they took to locate and reach to it. Coordinating the eye and the hand appropriately would markedly reduce the search-reach time. Using statistical decision theory we derived the sequence of interrelated eye and hand movements that would maximize expected gain and we predicted how hand movements should change as the eye gathered further information about target location. We recorded human observers' eye movements and hand movements and compared them with the optimal strategy that would have maximized expected gain. We found that most observers failed to adopt the optimal search-reach strategy. We analyze and describe the strategies they did adopt.

Zhang, Hang; Morvan, Camille; Etezad-Heydari, Louis-Alexandre; Maloney, Laurence T.

2012-01-01

62

A Fully 4D Expectation Maximization Algorithm Using Gaussian Diffusion Based Detector Response for Slow Camera Rotation Dynamic SPECT 1  

Microsoft Academic Search

The dynamic expectation maximization algorithm (dEM) has been developed to determine the kinetic information of various metabolic processes from SPECT projection data acquired with a single slow camera rotation. Depth-dependent detector response compensation (DRC) has been tested as a means to improve the accuracy of these reconstructions. As well, by limiting the number of temporal frames in a dSPECT reconstruction,

T. H. Farncombe; M. A. King; A. M. Celler; S. Blinder

63

An Expectation-Maximization Method for Spatio-Temporal Blind Source Separation Using an AR-MOG Source Model  

PubMed Central

In this paper, we develop a maximum-likelihood (ML) spatio-temporal blind source separation (BSS) algorithm, where the temporal dependencies are explained by assuming that each source is an autoregressive (AR) process and the distribution of the associated independent identically distributed (i.i.d.) inovations process is described using a mixture of Gaussians. Unlike most ML methods, the proposed algorithm takes into account both spatial and temporal information, optimization is performed using the expectation-maximization (EM) method, the source model is adapted to maximize the likelihood, and the update equations have a simple, analytical form. The proposed method, which we refer to as autoregressive mixture of Gaussians (AR-MOG), outperforms nine other methods for artificial mixtures of real audio. We also show results for using AR-MOG to extract the fetal cardiac signal from real magnetocardiographic (MCG) data.

Hild, Kenneth E.; Attias, Hagai T.; Nagarajan, Srikantan S.

2009-01-01

64

Expected Utility of Content Blocks in Web Content Extraction  

Microsoft Academic Search

In this paper we discuss the possible application of new concept s in web content extraction: utility assessment, utility annealing, and dynamic aggregated document generation. After analysis of the state of the art in web content extraction, results of a survey study among Polish managers are presented. The discussion covers a web content extraction system with possible extensions that may

Marek Kowalkiewicz

2006-01-01

65

Distributed network utility maximization using event-triggered augmented Lagrangian methods  

Microsoft Academic Search

Many problems associated with networked systems can be formulated as network utility maximization (NUM) problems. Dual decomposition is a widely used distributed algorithm that solves the NUM problem. This approach, however, uses a step size that is inversely proportional to measures of network size such as maximum path length or maximum neighborhood size. As a result, the number of messages

Pu Wan; Michael D. Lemmon

2009-01-01

66

The Impact of Stochastic Noisy Feedback on Distributed Network Utility Maximization  

Microsoft Academic Search

The implementation of distributed network utility maximization (NUM) algorithms hinges heavily on information feedback through message passing among network elements. In practical systems the feedback is often obtained using error- prone measurement mechanisms and suffers from random errors. There has been little work in this direction, and by and large the impact of noisy feedback remains open. A main objective

Junshan Zhang; Dong Zheng; Mung Chiang

2007-01-01

67

Stochastic Network Utility Maximization A tribute to Kelly's paper published in this journal a decade ago  

Microsoft Academic Search

SUMMARY Since the seminal work by Kelly on distributed network resource allocation using the language of Network Utility Maximization (NUM) a decade ago, there have been extensive research efforts generalizing and applying NUM to model, analyze, and design various network protocols and architectures. Some of these works combine the distributed optimization approach with stochastic network models to study NUM under

Yung Yi; Mung Chiang

2008-01-01

68

Maximizing network utilization with max-min fairness in wireless sensor networks  

Microsoft Academic Search

The state of the art for optimal data-gathering in wireless sensor networks is to use additive increase algorithms to achieve fair rate allocation while implicity trying to maximize network utilization. For the quantification of the problem we present a receiver capacity model to capture the interference existing in a wireless network. We also provide empirical evidence to motivate the applicability

Avinash Sridharan; Bhaskar Krishnamachari

2009-01-01

69

Balancing Supply and Demand of Bandwidth in Wireless Cellular Networks: Utility Maximization over Powers and Rates  

Microsoft Academic Search

In wireless cellular networks and wireless local area networks, nonlinear network utility maximization need to be con- ducted over both user rates and transmit powers. For each of the three cases considered in this paper, we present an algorithm that converges to the jointly optimal pair of rate vector and power vec- tor. For the simple case when data rates

Mung Chiang; Jason Bell

2004-01-01

70

Reconsideration of the Best Batting Order in Baseball: Is the Order to Maximize the Expected Number of Runs Really the Best?  

Microsoft Academic Search

In previous studies for analyzing the batting order of baseball games, the order is evaluated by its expected number of runs scored in a game, under the Markov chain model on the D’Esopo and Lefkowitz runner advancement model. However, the order to maximize the expected number of runs may not be the best order in the sense that it may

Nobuyoshi Hirotsu

2011-01-01

71

Hemodynamic segmentation of brain perfusion images with delay and dispersion effects using an expectation-maximization algorithm.  

PubMed

Automatic identification of various perfusion compartments from dynamic susceptibility contrast magnetic resonance brain images can assist in clinical diagnosis and treatment of cerebrovascular diseases. The principle of segmentation methods was based on the clustering of bolus transit-time profiles to discern areas of different tissues. However, the cerebrovascular diseases may result in a delayed and dispersed local perfusion and therefore alter the hemodynamic signal profiles. Assessing the accuracy of the segmentation technique under delayed/dispersed circumstance is critical to accurately evaluate the severity of the vascular disease. In this study, we improved the segmentation method of expectation-maximization algorithm by using the results of hierarchical clustering on whitened perfusion data as initial parameters for a mixture of multivariate Gaussians model. In addition, Monte Carlo simulations were conducted to evaluate the performance of proposed method under different levels of delay, dispersion, and noise of signal profiles in tissue segmentation. The proposed method was used to classify brain tissue types using perfusion data from five normal participants, a patient with unilateral stenosis of the internal carotid artery, and a patient with moyamoya disease. Our results showed that the normal, delayed or dispersed hemodynamics can be well differentiated for patients, and therefore the local arterial input function for impaired tissues can be recognized to minimize the error when estimating the cerebral blood flow. Furthermore, the tissue in the risk of infarct and the tissue with or without the complementary blood supply from the communicating arteries can be identified. PMID:23894386

Lu, Chia-Feng; Guo, Wan-Yuo; Chang, Feng-Chi; Huang, Shang-Ran; Chou, Yen-Chun; Wu, Yu-Te

2013-01-01

72

Hybrid genetic and variational expectation-maximization algorithm for gaussian-mixture-model-based brain MR image segmentation.  

PubMed

The expectation-maximization (EM) algorithm has been widely applied to the estimation of gaussian mixture model (GMM) in brain MR image segmentation. However, the EM algorithm is deterministic and intrinsically prone to overfitting the training data and being trapped in local optima. In this paper, we propose a hybrid genetic and variational EM (GA-VEM) algorithm for brain MR image segmentation. In this approach, the VEM algorithm is performed to estimate the GMM, and the GA is employed to initialize the hyperparameters of the conjugate prior distributions of GMM parameters involved in the VEM algorithm. Since GA has the potential to achieve global optimization and VEM can steadily avoid overfitting, the hybrid GA-VEM algorithm is capable of overcoming the drawbacks of traditional EM-based methods. We compared our approach to the EM-based, VEM-based, and GA-EM based segmentation algorithms, and the segmentation routines used in the statistical parametric mapping package and FMRIB Software Library in 20 low-resolution and 17 high-resolution brain MR studies. Our results show that the proposed approach can improve substantially the performance of brain MR image segmentation. PMID:21233052

Tian, GuangJian; Xia, Yong; Zhang, Yanning; Feng, Dagan

2011-05-01

73

Development of a fully 3D system model in iterative expectation-maximization reconstruction for cone-beam SPECT  

NASA Astrophysics Data System (ADS)

In order to improve reconstructed image quality for cone-beam collimator SPECT, we have developed and implemented a fully 3D reconstruction, using an ordered subsets expectation maximization (OSEM) algorithm, along with a volumetric system model - cone-volume system model (CVSM), a modified attenuation compensation, and a 3D depth- and angle-dependent resolution and sensitivity correction. SPECT data were acquired in a 128×128 matrix, in 120 views with a single circular orbit. Two sets of numerical Defrise phantoms were used to simulate CBC SPECT scans, and low noise and scatter-free projection datasets were obtained using the SimSET Monte Carlo package. The reconstructed images, obtained using OSEM with a line-length system model (LLSM) and a 3D Gaussian post-filter, and OSEM with FVSM and a 3D Gaussian post-filter were quantitatively studied. Overall improvement in the image quality has been observed, including better transaxial resolution, higher contrast-to-noise ratio between hot and cold disks, and better accuracy and lower bias in OSEM-CVSM, compared with OSEM-LLSM.

Ye, Hongwei; Vogelsang, Levon; Feiglin, David H.; Lipson, Edward D.; Krol, Andrzej

2008-04-01

74

Expectation-Maximization Algorithm for Determining Natural Selection of Y-Linked Genes Through Two-Sex Branching Processes  

PubMed Central

Abstract A two-dimensional bisexual branching process has recently been presented for the analysis of the generation-to-generation evolution of the number of carriers of a Y-linked gene. In this model, preference of females for males with a specific genetic characteristic is assumed to be determined by an allele of the gene. It has been shown that the behavior of this kind of Y-linked gene is strongly related to the reproduction law of each genotype. In practice, the corresponding offspring distributions are usually unknown, and it is necessary to develop their estimation theory in order to determine the natural selection of the gene. Here we deal with the estimation problem for the offspring distribution of each genotype of a Y-linked gene when the only observable data are each generation's total numbers of males of each genotype and of females. We set out the problem in a non parametric framework and obtain the maximum likelihood estimators of the offspring distributions using an expectation-maximization algorithm. From these estimators, we also derive the estimators for the reproduction mean of each genotype and forecast the distribution of the future population sizes. Finally, we check the accuracy of the algorithm by means of a simulation study.

Gonzalez, M.; Martinez, R.

2012-01-01

75

Expectation-maximization algorithms for learning a finite mixture of univariate survival time distributions from partially specified class values  

SciTech Connect

Heterogeneity exists on a data set when samples from di#11;erent classes are merged into the data set. Finite mixture models can be used to represent a survival time distribution on heterogeneous patient group by the proportions of each class and by the survival time distribution within each class as well. The heterogeneous data set cannot be explicitly decomposed to homogeneous subgroups unless all the samples are precisely labeled by their origin classes; such impossibility of decomposition is a barrier to overcome for estimating #12;nite mixture models. The expectation-maximization (EM) algorithm has been used to obtain maximum likelihood estimates of #12;nite mixture models by soft-decomposition of heterogeneous samples without labels for a subset or the entire set of data. In medical surveillance databases we can find partially labeled data, that is, while not completely unlabeled there is only imprecise information about class values. In this study we propose new EM algorithms that take advantages of using such partial labels, and thus incorporate more information than traditional EM algorithms. We particularly propose four variants of the EM algorithm named EM-OCML, EM-PCML, EM-HCML and EM-CPCML, each of which assumes a specific mechanism of missing class values. We conducted a simulation study on exponential survival trees with five classes and showed that the advantages of incorporating substantial amount of partially labeled data can be highly signi#12;cant. We also showed model selection based on AIC values fairly works to select the best proposed algorithm on each specific data set. A case study on a real-world data set of gastric cancer provided by Surveillance, Epidemiology and End Results (SEER) program showed a superiority of EM-CPCML to not only the other proposed EM algorithms but also conventional supervised, unsupervised and semi-supervised learning algorithms.

Lee, Youngrok [Ames Laboratory

2013-05-15

76

Partial volume correction of PET-imaged tumor heterogeneity using expectation maximization with a spatially varying point spread function  

PubMed Central

Tumor heterogeneities observed in positron emission tomography (PET) imaging are frequently compromised of partial volume effects which may affect treatment prognosis, assessment, or future implementations such as biologically optimized treatment planning (dose painting). This paper presents a method for partial volume correction of PET-imaged heterogeneous tumors. A point source was scanned on a GE Discover LS at positions of increasing radii from the scanner’s center to obtain the spatially varying point spread function (PSF). PSF images were fit in three dimensions to Gaussian distributions using least squares optimization. Continuous expressions were devised for each Gaussian width as a function of radial distance, allowing for generation of the system PSF at any position in space. A spatially varying partial volume correction (SV-PVC) technique was developed using expectation maximization (EM) and a stopping criterion based on the method’s correction matrix generated for each iteration. The SV-PVC was validated using a standard tumor phantom and a tumor heterogeneity phantom, and was applied to a heterogeneous patient tumor. SV-PVC results were compared to results obtained from spatially invariant partial volume correction (SINV-PVC), which used directionally uniform three dimensional kernels. SV-PVC of the standard tumor phantom increased the maximum observed sphere activity by 55 and 40% for 10 and 13 mm diameter spheres, respectively. Tumor heterogeneity phantom results demonstrated that as net changes in the EM correction matrix decreased below 35%, further iterations improved overall quantitative accuracy by less than 1%. SV-PVC of clinically observed tumors frequently exhibited changes of ±30% in regions of heterogeneity. The SV-PVC method implemented spatially varying kernel widths and automatically determined the number of iterations for optimal restoration, parameters which are arbitrarily chosen in SINV-PVC. Comparing SV-PVC to SINV-PVC demonstrated that similar results could be reached using both methods, but large differences result for the arbitrary selection of SINV-PVC parameters. The presented SV-PVC method was performed without user intervention, requiring only a tumor mask as input. Research involving PET-imaged tumor heterogeneity should include correcting for partial volume effects to improve the quantitative accuracy of results.

Barbee, David L; Flynn, Ryan T; Holden, James E; Nickles, Robert J; Jeraj, Robert

2010-01-01

77

Optimization of Ordered Subset Expectation Maximization Reconstruction for Reducing Urinary Bladder Artifacts in Single-photon Emission Computed Tomography Imaging  

PubMed Central

Bladder artifact during bone single-photon emission computed tomography (SPECT) is a common source of error. The extent and severity of bladder artifacts have been described for filtered back projection (FBP) reconstruction. Ordered subset expectation maximization (OSEM) may help to address this problem of bladder artifacts, which render up to 20% of the SPECT images unreadable. The objective of this study was to evaluate the relationship of the bladder to acetabulum ratio in guiding the choice of the number of iterations and subsets used for OSEM reconstruction, for reducing bladder artifacts found on FBP reconstruction. One hundred five patients with various indications for bone scans were selected and planar and SPECT images were acquired. The SPECT images were reconstructed with both FBP and OSEM using four different combinations of iterations and subsets. The images were given to three experienced nuclear physicians who were blinded to the diagnosis and type of reconstruction used. They then labeled images from the best to the worst after which the data were analyzed. The bladder to acetabulum ratio for each image was determined which was then correlated with the different iterations and subsets used. The study demonstrated that reconstruction using OSEM led to better lesion detectability compared to FBP in 87.62% of cases. It further demonstrated that the iterations and subsets used for reconstruction of an image correlate with the bladder to acetabulum ratio. Four iterations and 8 subsets yielded the best results in 48.5% of the images, whilst 2 iterations and 8 subsets yielded the best results in 33.8%. The number of reconstructed images which yielded the best results with 2 iterations and 8 subsets was the same as or more than those with 4 iterations and 8 subsets when the bladder/acetabulum ratio (A/B) was between 0.2 and 0.39. A ratio below 0.2 or above 0.39 supports the usage of 4 iterations and 8 subsets over 2 iterations and 8 subsets. We conclude that bladder to acetabulum ratio can be used to select the optimum number of iterations and subsets for reconstruction of bone SPECT for accurate characterization of lesions. This study also confirms that reconstruction with OSEM (vs. FBP) leads to better lesion detectability and characterization.

Katua, A. M.; Ankrah, A. O.; Vorster, M.; van Gelder, A.; Sathekge, M. M.

2011-01-01

78

Expectation-maximization-driven geodesic active contour with overlap resolution (EMaGACOR): application to lymphocyte segmentation on breast cancer histopathology.  

PubMed

The presence of lymphocytic infiltration (LI) has been correlated with nodal metastasis and tumor recurrence in HER2+ breast cancer (BC). The ability to automatically detect and quantify extent of LI on histopathology imagery could potentially result in the development of an image based prognostic tool for human epidermal growth factor receptor-2 (HER2+) BC patients. Lymphocyte segmentation in hematoxylin and eosin (H&E) stained BC histopathology images is complicated by the similarity in appearance between lymphocyte nuclei and other structures (e.g., cancer nuclei) in the image. Additional challenges include biological variability, histological artifacts, and high prevalence of overlapping objects. Although active contours are widely employed in image segmentation, they are limited in their ability to segment overlapping objects and are sensitive to initialization. In this paper, we present a new segmentation scheme, expectation-maximization (EM) driven geodesic active contour with overlap resolution (EMaGACOR), which we apply to automatically detecting and segmenting lymphocytes on HER2+ BC histopathology images. EMaGACOR utilizes the expectation-maximization algorithm for automatically initializing a geodesic active contour (GAC) and includes a novel scheme based on heuristic splitting of contours via identification of high concavity points for resolving overlapping structures. EMaGACOR was evaluated on a total of 100 HER2+ breast biopsy histology images and was found to have a detection sensitivity of over 86% and a positive predictive value of over 64%. By comparison, the EMaGAC model (without overlap resolution) and GAC model yielded corresponding detection sensitivities of 42% and 19%, respectively. Furthermore, EMaGACOR was able to correctly resolve over 90% of overlaps between intersecting lymphocytes. Hausdorff distance (HD) and mean absolute distance (MAD) for EMaGACOR were found to be 2.1 and 0.9 pixels, respectively, and significantly better compared to the corresponding performance of the EMaGAC and GAC models. EMaGACOR is an efficient, robust, reproducible, and accurate segmentation technique that could potentially be applied to other biomedical image analysis problems. PMID:20172780

Fatakdawala, Hussain; Xu, Jun; Basavanhally, Ajay; Bhanot, Gyan; Ganesan, Shridar; Feldman, Michael; Tomaszewski, John E; Madabhushi, Anant

2010-07-01

79

Efficient algorithms for training the parameters of hidden Markov models using stochastic expectation maximization (EM) training and Viterbi training  

Microsoft Academic Search

BACKGROUND: Hidden Markov models are widely employed by numerous bioinformatics programs used today. Applications range widely from comparative gene prediction to time-series analyses of micro-array data. The parameters of the underlying models need to be adjusted for specific data sets, for example the genome of a particular species, in order to maximize the prediction accuracy. Computationally efficient algorithms for parameter

Tin Y Lam; Irmtraud M Meyer

2010-01-01

80

The temporal derivative of expected utility: a neural mechanism for dynamic decision-making.  

PubMed

Real world tasks involving moving targets, such as driving a vehicle, are performed based on continuous decisions thought to depend upon the temporal derivative of the expected utility (?V/?t), where the expected utility (V) is the effective value of a future reward. However, the neural mechanisms that underlie dynamic decision-making are not well understood. This study investigates human neural correlates of both V and ?V/?t using fMRI and a novel experimental paradigm based on a pursuit-evasion game optimized to isolate components of dynamic decision processes. Our behavioral data show that players of the pursuit-evasion game adopt an exponential discounting function, supporting the expected utility theory. The continuous functions of V and ?V/?t were derived from the behavioral data and applied as regressors in fMRI analysis, enabling temporal resolution that exceeded the sampling rate of image acquisition, hyper-temporal resolution, by taking advantage of numerous trials that provide rich and independent manipulation of those variables. V and ?V/?t were each associated with distinct neural activity. Specifically, ?V/?t was associated with anterior and posterior cingulate cortices, superior parietal lobule, and ventral pallidum, whereas V was primarily associated with supplementary motor, pre and post central gyri, cerebellum, and thalamus. The association between the ?V/?t and brain regions previously related to decision-making is consistent with the primary role of the temporal derivative of expected utility in dynamic decision-making. PMID:22963852

Zhang, Xian; Hirsch, Joy

2013-01-15

81

The role of data assimilation in maximizing the utility of geospace observations (Invited)  

NASA Astrophysics Data System (ADS)

Data assimilation can facilitate maximizing the utility of existing geospace observations by offering an ultimate marriage of inductive (data-driven) and deductive (first-principles based) approaches to addressing critical questions in space weather. Assimilative approaches that incorporate dynamical models are, in particular, capable of making a diverse set of observations consistent with physical processes included in a first-principles model, and allowing unobserved physical states to be inferred from observations. These points will be demonstrated in the context of the application of an ensemble Kalman filter (EnKF) to a thermosphere and ionosphere general circulation model. An important attribute of this approach is that the feedback between plasma and neutral variables is self-consistently treated both in the forecast model as well as in the assimilation scheme. This takes advantage of the intimate coupling between the thermosphere and ionosphere described in general circulation models to enable the inference of unobserved thermospheric states from the relatively plentiful observations of the ionosphere. Given the ever-growing infrastructure for the global navigation satellite system, this is indeed a promising prospect for geospace data assimilation. In principle, similar approaches can be applied to any geospace observing systems to extract more geophysical information from a given set of observations than would otherwise be possible.

Matsuo, T.

2013-12-01

82

Optimal Decision-Making of Countermeasures by Estimating Their Expected Utilities  

NASA Astrophysics Data System (ADS)

This paper investigates the autonomous decision-making process of the selection of alternative countermeasures against threats in electronic warfare settings. We introduce a threat model, which represents a specific threat pattern, and a methodology that decides the best countermeasure against real-time threats using the decision theory. To determine the optimal countermeasure, we model the probabilities of the effects of countermeasures, if executed, and combine the probabilities with their utilities. This methodology based upon the inductive threat model calculates the expected utilities of countermeasures which are applicable given a situation, and provide an intelligent command and control agent with the best countermeasure to threats. We present empirical results that demonstrate the agent's capabilities of choosing countermeasures to threats in simulated electronic warfare settings.

Park, So Ryoung; Noh, Sanguk

83

New method for tuning hyperparameter for the total variation norm in the maximum a posteriori ordered subsets expectation maximization reconstruction in SPECT myocardial perfusion imaging  

NASA Astrophysics Data System (ADS)

In order to improve the tradeoff between noise and bias, and to improve uniformity of the reconstructed myocardium while preserving spatial resolution in parallel-beam collimator SPECT myocardial perfusion imaging (MPI) we investigated the most advantageous approach to provide reliable estimate of the optimal value of hyperparameter for the Total Variation (TV) norm in the iterative Bayesian Maximum A Posteriori Ordered Subsets Expectation Maximization (MAP-OSEM) one step late tomographic reconstruction with Gibbs prior. Our aim was to find the optimal value of hyperparameter corresponding to the lowest bias at the lowest noise while maximizing uniformity and spatial resolution for the reconstructed myocardium in SPECT MPI. We found that the L-curve method that is by definition a global technique provides good guidance for selection of the optimal value of the hyperparameter. However, for a heterogeneous object such as human thorax the fine-tuning of the hyperparameter's value can be only accomplished by means of a local method such as the proposed bias-noise distance (BND) curve. We established that our BND-curve method provides accurate optimized hyperparameter's value estimation as long as the region of interest volume for which it is defined is sufficiently large and is located sufficiently close to the myocardium.

Yang, Zhaoxia; Krol, Andrzej; Xu, Yuesheng; Feiglin, David H.

2011-03-01

84

Classification of spatiotemporal hemodynamics from brain perfusion MR images using expectation-maximization estimation with finite mixture of multivariate gaussian distributions.  

PubMed

The ability to cluster different perfusion compartments in the brain is critical for analyzing brain perfusion. This study presents a method based on a mixture of multivariate Gaussians (MoMG) and the expectation-maximization (EM) algorithm to dissect various perfusion compartments from dynamic susceptibility contrast (DSC) MR images so that each compartment comprises pixels of similar signal-time curves. This EM-based method provides an objective way to 1) delineate an area to serve as the in-plane arterial input function (AIF) of the feeding artery for adjacent tissues to better quantify the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT); 2) demarcate regions with abnormal perfusion derangement to facilitate diagnosis; and 3) obtain parametric maps with supplementary information, such as temporal scenarios and recirculation of contrast agent. Results from normal subjects show that perfusion cascade manifests (in order of appearance) the arteries, gray matter (GM), white matter (WM), veins and sinuses, and choroid plexus mixed with cerebrospinal fluid (CSF). The averaged rCBV, rCBF, and MTT ratios between GM and WM are in good agreement with those in the literature. Results from a patient with cerebral arteriovenous malformation (CAVM) showed distinct spatiotemporal characteristics between perfusion patterns, which allowed differentiation between pathological and nonpathological areas. PMID:17191233

Wu, Yu-Te; Chou, Yen-Chun; Guo, Wan-Yuo; Yeh, Tzu-Chen; Hsieh, Jen-Chuen

2007-01-01

85

Non-linear spatio-temporal filtering of dynamic PET data using a 4-dimensional Gaussian filter and expectation-maximization deconvolution  

PubMed Central

We introduce a method for denoising dynamic PET data, spatio-temporal expectation-maximization (STEM) filtering, that combines 4-dimensional Gaussian filtering with EM deconvolution. The initial Gaussian filter suppresses noise at a broad range of spatial and temporal frequencies and EM deconvolution quickly restores the frequencies most important to the signal. We aim to demonstrate that STEM filtering can improve variance in both individual time frames and in parametric images without introducing significant bias. We evaluate STEM filtering with a dynamic phantom study, and with simulated and human dynamic PET studies of a tracer with reversible binding behaviour, [C-11]raclopride, and a tracer with irreversible binding behaviour, [F-18]FDOPA. STEM filtering is compared to a number of established 3 and 4-dimensional denoising methods. STEM filtering provides substantial improvements in variance in both individual time frames and in parametric images generated with a number of kinetic analysis techniques while introducing little bias. STEM filtering does bias early frames, but this does not affect quantitative parameter estimates. STEM filtering is shown to be superior to the other simple denoising methods studied. STEM filtering is a simple and effective denoising method that could be valuable for a wide range of dynamic PET applications.

Holden, J E

2013-01-01

86

Evaluation of list-mode ordered subset expectation maximization image reconstruction for pixelated solid-state compton gamma camera with large number of channels  

NASA Astrophysics Data System (ADS)

The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For Compton camera, especially with a large number of readout channels, image reconstruction presents a big challenge. In this work, results are presented for the List-Mode Ordered Subset Expectation Maximization (LM-OSEM) image reconstruction algorithm on simulated data with the VIP Compton camera design. For the simulation, all realistic contributions to the spatial resolution are taken into account, including the Doppler broadening effect. The results show that even with a straightforward implementation of LM-OSEM, good images can be obtained for the proposed Compton camera design. Results are shown for various phantoms, including extended sources and with a distance between the field of view and the first detector plane equal to 100 mm which corresponds to a realistic nuclear medicine environment.

Kolstein, M.; De Lorenzo, G.; Chmeissani, M.

2014-04-01

87

Utilizing expectations to measure economic depreciation and capital gains of farm machinery  

Microsoft Academic Search

Rather than relying on ex post market data, this study derives theoretically more appropriate measures of economic depreciation and capital gains based on the expectations of farmers. In this context, values of depreciable assets are highly sensitive to the pattern of expected future earnings and unexpected windfall gains. Experimental survey data obtained from a panel of Illinois cash grain farmers

Cole R. Gustafson; Peter J. Barry; Steven T. Sonka

1990-01-01

88

Population genetic analysis of bi-allelic structural variants from low-coverage sequence data with an expectation-maximization algorithm  

PubMed Central

Background Population genetics and association studies usually rely on a set of known variable sites that are then genotyped in subsequent samples, because it is easier to genotype than to discover the variation. This is also true for structural variation detected from sequence data. However, the genotypes at known variable sites can only be inferred with uncertainty from low coverage data. Thus, statistical approaches that infer genotype likelihoods, test hypotheses, and estimate population parameters without requiring accurate genotypes are becoming popular. Unfortunately, the current implementations of these methods are intended to analyse only single nucleotide and short indel variation, and they usually assume that the two alleles in a heterozygous individual are sampled with equal probability. This is generally false for structural variants detected with paired ends or split reads. Therefore, the population genetics of structural variants cannot be studied, unless a painstaking and potentially biased genotyping is performed first. Results We present svgem, an expectation-maximization implementation to estimate allele and genotype frequencies, calculate genotype posterior probabilities, and test for Hardy-Weinberg equilibrium and for population differences, from the numbers of times the alleles are observed in each individual. Although applicable to single nucleotide variation, it aims at bi-allelic structural variation of any type, observed by either split reads or paired ends, with arbitrarily high allele sampling bias. We test svgem with simulated and real data from the 1000 Genomes Project. Conclusions svgem makes it possible to use low-coverage sequencing data to study the population distribution of structural variants without having to know their genotypes. Furthermore, this advance allows the combined analysis of structural and nucleotide variation within the same genotype-free statistical framework, thus preventing biases introduced by genotype imputation.

2014-01-01

89

Estimating the Probability Weighting Function used in non-Expected Utility Theory: A case study of mutual fund managers  

Microsoft Academic Search

This dissertation investigates the Probability Weighting Function (PWF), a determinant of individual choice behavior and a key aspect of non Expected Utility Theories (EUT). We focus on mutual fund managers as decision makers and their holdings as reflections of their decisions. In this study we argue that it is possible to improve our understanding and practice of decision making by

Diana Ramona Rudean

2009-01-01

90

Pt Skin on AuCu Intermetallic Substrate: A Strategy to Maximize Pt Utilization for Fuel Cells.  

PubMed

The dependence on Pt catalysts has been a major issue of proton-exchange membrane (PEM) fuel cells. Strategies to maximize the Pt utilization in catalysts include two main approaches: to put Pt atoms only at the catalyst surface and to further enhance the surface-specific catalytic activity (SA) of Pt. Thus far there has been no practical design that combines these two features into one single catalyst. Here we report a combined computational and experimental study on the design and implementation of Pt-skin catalysts with significantly improved SA toward the oxygen reduction reaction (ORR). Through screening, using density functional theory (DFT) calculations, a Pt-skin structure on AuCu(111) substrate, consisting of 1.5 monolayers of Pt, is found to have an appropriately weakened oxygen affinity, in comparison to that on Pt(111), which would be ideal for ORR catalysis. Such a structure is then realized by substituting the Cu atoms in three surface layers of AuCu intermetallic nanoparticles (AuCu iNPs) with Pt. The resulting Pt-skinned catalyst (denoted as Pt(S)AuCu iNPs) has been characterized in depth using synchrotron XRD, XPS, HRTEM, and HAADF-STEM/EDX, such that the Pt-skin structure is unambiguously identified. The thickness of the Pt skin was determined to be less than two atomic layers. Finally the catalytic activity of Pt(S)AuCu iNPs toward the ORR was measured via rotating disk electrode (RDE) voltammetry through which it was established that the SA was more than 2 times that of a commercial Pt/C catalyst. Taking into account the ultralow Pt loading in Pt(S)AuCu iNPs, the mass-specific catalytic activity (MA) was determined to be 0.56 A/mgPt@0.9 V, a value that is well beyond the DOE 2017 target for ORR catalysts (0.44 A/mgPt@0.9 V). These findings provide a strategic design and a realizable approach to high-performance and Pt-efficient catalysts for fuel cells. PMID:24936859

Wang, Gongwei; Huang, Bing; Xiao, Li; Ren, Zhandong; Chen, Hao; Wang, Deli; Abruña, Héctor D; Lu, Juntao; Zhuang, Lin

2014-07-01

91

Great Expectations.  

ERIC Educational Resources Information Center

Discusses how some universities are proactively looking to improve, enhance, and increase student housing on-campus through new and renovated residence halls that meet and exceed the expectations of today's students. Renovation improvements related to maximizing security, enhancing a homelike environment; developing a sense of community, and…

Smith, Jana J.

2000-01-01

92

Utilizing Maximum Power Point Trackers in Parallel to Maximize the Power Output of a Solar (Photovoltaic) Array.  

National Technical Information Service (NTIS)

It is common when optimizing a photovoltaic (PV) system to use a maximum power point tracker (MPPT) to increase the power output of the solar array. Currently, most military applications that utilize solar energy omit or use only a single MPPT per PV syst...

C. A. Stephenson

2012-01-01

93

Aspects concerning entropy and utility  

Microsoft Academic Search

Expected utility maximization problem is one of the most useful tools in mathematical finance, decision analysis and economics.\\u000a Motivated by statistical model selection, via the principle of expected utility maximization, Friedman and Sandow (J Mach\\u000a Learn Res 4:257–291, 2003a) considered the model performance question from the point of view of an investor who evaluates\\u000a models based on the performance of

A. R. Hoseinzadeh; G. R. Mohtashami Borzadaran; G. H. Yari

2012-01-01

94

Maximizing operational effectiveness and utility of the Mobile Infrared Scene Projector (MIRSP) during System Integration Laboratory (SIL) testing  

NASA Astrophysics Data System (ADS)

Testing advanced weapons systems, like the Comanche helicopter, has always presented technical challenges to the Test and Evaluation (T&E) community. Because these weapon systems are on the cutting edge of technology, it is the tester's responsibility to develop the tools and techniques to fully exercise a new weapon system's capability. As with most testing, state-of-the-art tools which provide test stimuli that matches or exceeds the fidelity of the systems under test must be developed. One such tool under development to test FLIR senors is the Mobile Infrared Scene Projector (MIRSP). This paper will investigate current plans to support the T&E of the Comanche FLIR sensor during SIL testing. Planning the T&E usage of the MIRSP has involved identifying limitations, both in hardware and software, and determining how to minimize the effects of these limitations or proposing solutions to correct these limitations. The final result of this effort is to maximize the operational effectiveness of the MIRSP in order to benefit T&E of all FLIR sensors in the future.

Zabel, Kenneth W.; Brooks, Geoffrey W.; Owens, Bruce

2000-07-01

95

Variation of epimedins A?-?C and icariin in ten representative populations of Epimedium brevicornu Maxim., and implications for utilization.  

PubMed

The concentration variations of main flavonoids, epimedins A-C and icariin, among ten representative populations of Epimedium brevicornu Maxim. were assessed by HPLC. The populations were collected during the flowering stage and included 419 individual samples. Remarkable variations within and among populations were detected. SXXA Population (see Fig.?1) was an outlier due to its significant low concentrations (<1.00-4.46?mg/g). But even without SXXA, significant concentration differences among populations were still observed in epimedin A (2.31-8.42?mg/g), epimedin B (6.67-55.7?mg/g), epimedin C (5.39-23.0?mg/g), icariin (8.50-39.9?mg/g), and their total (29.1-123?mg/g). All populations except SXXA showed much higher concentrations than the recommended standards (i.e. 5?mg/g for icariin and 13?mg/g for the total). A high-concentration-population structure, estimated both by principal component analysis (PCA) and unweighted pair group method with averaging (UPGMA) cluster analysis, based on Euclidean distances, was observed. Both methods allowed separation of the populations in four groups defined by the concentrations of four main flavonoids. The populations (SXLC and SXQS) located in north of Yellow River were clustered together and characterized by highest concentrations of epimedin B, icariin, and their total. Considering of the high concentrations of main flavonoids and abundant resources, E. brevicornu could be exploited as a good medical resource for Herba Epimedii and would offer a tremendous potential for commercial development, but SXXA population should be paid special attention, and further study is needed. PMID:23576357

Xu, Yanqin; Li, Zuozhou; Yuan, Ling; Zhang, Xuejun; Lu, Dayan; Huang, Hongwen; Wang, Ying

2013-04-01

96

Expectation Maximization for Clustering on Hyperspheres  

Microsoft Academic Search

High dimensional directional data is becoming increasingly important in contemporary ap- plications such as analysis of text and gene-expression data. A natural model for multi-variate directional data is provided by the von Mises-Fisher (vMF) distribution on the unit hypersphere that is analogous to multi-variate Gaussian distribution in Rd. In this paper, we propose mod- eling complex directional data as a

Arindam Banerjee; Inderjit Dhillon; Joydeep Ghosh; Suvrit Sra

2003-01-01

97

Expectation Maximization for Clustering on Hyperspheres  

Microsoft Academic Search

High dimensional directional data is becoming increasingly important in contemporary ap- plications such as analysis of text and gene-expression data. A natural model for multi-variate directional data is provided by the von Mises-Fisher (vMF) distribution on the unit hypersphere that is analogous to multi-variate Gaussian distribution in Rd. In this paper, we propose mod- eling complex directional data as a

Arindam Banerjee; Inderjit Dhillony; Joydeep Ghosh; Suvrit Sray

98

Maximizing Image Utilization in Photomosaics  

Microsoft Academic Search

Non-photo realistic rendering (NPR) is an appealing subject in computer graphics with a wide array of applications. As opposed to photo realistic rendering, NPR focuses on highlighting features and artistic traits instead of physical accuracy. Photo mosaic generation is one of the most popular NPR techniques, where a single image is assembled from several smaller ones. Visual responses change depending

Michihiro Mikamo; Marcos Slomp; Shungo Yanase; Bisser Raytchev; Toru Tamaki; Kazufumi Kaneda

2010-01-01

99

Resource utilization by children with developmental disabilities in Kenya: discrepancy analysis of parents’ expectation-to-importance appraisals  

Microsoft Academic Search

The purpose of this study was to describe parental perceptions of eight physical and human resources available to meet the needs of children with developmental disabilities in Kenya. Specifically, the study assessed the discrepancy between the importance parents attached to specified resources and the expected use of those resources by their children with developmental disabilities. Discrepancy analysis was conducted on

N. Kagendo Mutua; Janice Williams Miller; Mwarumba Mwavita

2002-01-01

100

Expected utility of voluntary vaccination in the middle of an emergent Bluetongue virus serotype 8 epidemic: A decision analysis parameterized for Dutch circumstances.  

PubMed

In order to put a halt to the Bluetongue virus serotype 8 (BTV-8) epidemic in 2008, the European Commission promoted vaccination at a transnational level as a new measure to combat BTV-8. Most European member states opted for a mandatory vaccination campaign, whereas the Netherlands, amongst others, opted for a voluntary campaign. For the latter to be effective, the farmer's willingness to vaccinate should be high enough to reach satisfactory vaccination coverage to stop the spread of the disease. This study looked at a farmer's expected utility of vaccination, which is expected to have a positive impact on the willingness to vaccinate. Decision analysis was used to structure the vaccination decision problem into decisions, events and payoffs, and to define the relationships among these elements. Two scenarios were formulated to distinguish farmers' mindsets, based on differences in dairy heifer management. For each of the scenarios, a decision tree was run for two years to study vaccination behaviour over time. The analysis was done based on the expected utility criterion. This allows to account for the effect of a farmer's risk preference on the vaccination decision. Probabilities were estimated by experts, payoffs were based on an earlier published study. According to the results of the simulation, the farmer decided initially to vaccinate against BTV-8 as the net expected utility of vaccination was positive. Re-vaccination was uncertain due to less expected costs of a continued outbreak. A risk averse farmer in this respect is more likely to re-vaccinate. When heifers were retained for export on the farm, the net expected utility of vaccination was found to be generally larger and thus was re-vaccination more likely to happen. For future animal health programmes that rely on a voluntary approach, results show that the provision of financial incentives can be adjusted to the farmers' willingness to vaccinate over time. Important in this respect are the decision moment and the characteristics of the disease. Farmers' perceptions of the disease risk and about the efficacy of available control options cannot be neglected. PMID:24768508

Sok, J; Hogeveen, H; Elbers, A R W; Velthuis, A G J; Oude Lansink, A G J M

2014-08-01

101

Reduced Maximal Inhibition in Phenotypic Susceptibility Assays Indicates that Viral Strains Resistant to the CCR5 Antagonist Maraviroc Utilize Inhibitor-Bound Receptor for Entry?  

PubMed Central

Maraviroc is a CCR5 antagonist in clinical development as one of a new class of antiretrovirals targeting human immunodeficiency virus type 1 (HIV-1) coreceptor binding. We investigated the mechanism of HIV resistance to maraviroc by using in vitro sequential passage and site-directed mutagenesis. Serial passage through increasing maraviroc concentrations failed to select maraviroc-resistant variants from some laboratory-adapted and clinical isolates of HIV-1. However, high-level resistance to maraviroc was selected from three of six primary isolates passaged in peripheral blood lymphocytes (PBL). The SF162 strain acquired resistance to maraviroc in both treated and control cultures; all resistant variants were able to use CXCR4 as a coreceptor. In contrast, maraviroc-resistant virus derived from isolates CC1/85 and RU570 remained CCR5 tropic, as evidenced by susceptibility to the CCR5 antagonist SCH-C, resistance to the CXCR4 antagonist AMD3100, and an inability to replicate in CCR5 ?32/?32 PBL. Strain-specific mutations were identified in the V3 loop of maraviroc-resistant CC1/85 and RU570. The envelope-encoding region of maraviroc-resistant CC1/85 was inserted into an NL4-3 background. This recombinant virus was completely resistant to maraviroc but retained susceptibility to aplaviroc. Reverse mutation of gp120 residues 316 and 323 in the V3 loop (numbering from HXB2) to their original sequence restored wild-type susceptibility to maraviroc, while reversion of either mutation resulted in a partially sensitive virus with reduced maximal inhibition (plateau). The plateaus are consistent with the virus having acquired the ability to utilize maraviroc-bound receptor for entry. This hypothesis was further corroborated by the observation that a high concentration of maraviroc blocks the activity of aplaviroc against maraviroc-resistant virus.

Westby, Mike; Smith-Burchnell, Caroline; Mori, Julie; Lewis, Marilyn; Mosley, Michael; Stockdale, Mark; Dorr, Patrick; Ciaramella, Giuseppe; Perros, Manos

2007-01-01

102

Expected Antenna Utilization and Overload.  

National Technical Information Service (NTIS)

The trade-offs between the number of antennas at Deep Space Network (DSN) Deep-Space Communications Complex and the fraction of continuous coverage provided to a set of hypothetical spacecraft, assuming random placement of the space craft passes during th...

E. C. Posner

1991-01-01

103

MEAN VARIANCE PREFERENCES, EXPECTATIONS FORMATION, AND THE DYNAMICS OF RANDOM ASSET PRICES  

Microsoft Academic Search

This paper analyzes the dynamics of an explicit random process of prices and price expectations of finitely many assets in an economy with overlapping generations of heterogeneous consumers. They maximize expected utility with respect to subjective transition probabilities defined by Markov kernels which describe the forecasting behavior of agents. Given such forecasting rules (predictors) and an exogenous process of dividends,

Volker Böhm; Carl Chiarella

2005-01-01

104

On deciding to have a lobotomy: either lobotomies were justified or decisions under risk should not always seek to maximise expected utility.  

PubMed

In the 1940s and 1950s thousands of lobotomies were performed on people with mental disorders. These operations were known to be dangerous, but thought to offer great hope. Nowadays, the lobotomies of the 1940s and 1950s are widely condemned. The consensus is that the practitioners who employed them were, at best, misguided enthusiasts, or, at worst, evil. In this paper I employ standard decision theory to understand and assess shifts in the evaluation of lobotomy. Textbooks of medical decision making generally recommend that decisions under risk are made so as to maximise expected utility (MEU) I show that using this procedure suggests that the 1940s and 1950s practice of psychosurgery was justifiable. In making sense of this finding we have a choice: Either we can accept that psychosurgery was justified, in which case condemnation of the lobotomists is misplaced. Or, we can conclude that the use of formal decision procedures, such as MEU, is problematic. PMID:24449251

Cooper, Rachel

2014-02-01

105

Prognostic utility of predischarge dipyridamole-thallium imaging compared to predischarge submaximal exercise electrocardiography and maximal exercise thallium imaging after uncomplicated acute myocardial infarction  

SciTech Connect

The prognostic value of predischarge dipyridamole-thallium scanning after uncomplicated myocardial infarction was determined by comparison with submaximal exercise electrocardiography and 6-week maximal exercise thallium imaging and by correlation with clinical events. Two endpoints were defined: cardiac events and severe ischemic potential. Of the 40 patients studied, 8 had cardiac events within 6 months (1 died, 3 had myocardial infarction and 4 had unstable angina requiring hospitalization). The finding of any redistribution on dipyridamole-thallium scanning was common (77%) in these patients and had poor specificity (29%). Redistribution outside of the infarct zone, however, had equivalent sensitivity (63%) and better specificity (75%) for events (p less than 0.05). Both predischarge dipyridamole-thallium and submaximal exercise electrocardiography identified 5 of the 8 events (p = 0.04 and 0.07, respectively). The negative predictive accuracy for events for both dipyridamole-thallium and submaximal exercise electrocardiography was 88%. In addition to the 8 patients with events, 16 other patients had severe ischemic potential (6 had coronary bypass surgery, 1 had inoperable 3-vessel disease and 9 had markedly abnormal 6-week maximal exercise tests). Predischarge dipyridamole-thallium and submaximal exercise testing also identified 8 and 7 of these 16 patients with severe ischemic potential, respectively. Six of the 8 cardiac events occurred before 6-week follow-up. A maximal exercise thallium test at 6 weeks identified 1 of the 2 additional events within 6 months correctly. Thallium redistribution after dipyridamole in coronary territories outside the infarct zone is a sensitive and specific predictor of subsequent cardiac events and identifies patients with severe ischemic potential.

Gimple, L.W.; Hutter, A.M. Jr.; Guiney, T.E.; Boucher, C.A. (Massachusetts General Hospital, Boston (USA))

1989-12-01

106

GUIDELINES FOR NOX CONTROL BY COMBUSTION MODIFICATION FOR COAL-FIRED UTILITY BOILERS. PROCEDURES FOR REDUCTION OF NOX EMISSIONS AND MAXIMIZATION OF BOILER EFFICIENCY  

EPA Science Inventory

The report, which has been reviewed by industry experts, reflects the experience developed in successfully applying combustion modifications to reduce NOx emissions from coal-fired utility boilers. Although the report emphasizes coal-fired equipment, the same principles can be ap...

107

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

SciTech Connect

This is the ninth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. The pilot-scale testing phase of the project has been completed. Calculations are essentially completed for implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. The REI Configurable Fireside Simulator (CFS) has proven to be an essential component to provide input for these calculations. Niksa Energy Associates expects to deliver their final report in February 2003. Work has continued on the project final report.

Larry G. Felix; P. Vann Bush

2003-01-29

108

Maximally Expressive Modeling  

NASA Technical Reports Server (NTRS)

Planning and scheduling systems organize tasks into a timeline or schedule. Tasks are logically grouped into containers called models. Models are a collection of related tasks, along with their dependencies and requirements, that when met will produce the desired result. One challenging domain for a planning and scheduling system is the operation of on-board experiments for the International Space Station. In these experiments, the equipment used is among the most complex hardware ever developed; the information sought is at the cutting edge of scientific endeavor; and the procedures are intricate and exacting. Scheduling is made more difficult by a scarcity of station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling International Space Station experiment operations calls for a maximally expressive modeling schema.

Jaap, John; Davis, Elizabeth; Richardson, Lea

2004-01-01

109

DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL  

SciTech Connect

This is the sixth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Two additional biomass co-firing test burns were conducted during this quarter. In the first test (Test 10), up to 20% by weight dry hardwood sawdust and switchgrass was compiled with Galatia coal and injected through the dual-register burner. Galatia coal is a medium-sulfur Illinois Basin coal ({approx}1.0% S). The dual-register burner is a generic low-NO{sub x} burner that incorporates two independent wind boxes. In the second test (Test 11), regular ({approx}70% passing 200 mesh) and finely ground ({approx}90% passing 200 mesh) Pratt Seam coal was injected through the single-register burner to determine if coal grind affects NO{sub x} and unburned carbon emissions. The results of these tests are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. No additional results of CFD modeling have been received as delivery of the Configurable Fireside Simulator is expected during the next quarter. Preparations are under way for continued pilot-scale combustion experiments with the single-register burner and a low-volatility bituminous coal. Some delays have been experienced in the acquisition and processing of biomass. Finally, a project review was held at the offices of Southern Research in Birmingham, on February 27, 2002.

Larry G. Felix; P. Vann Bush

2002-04-30

110

Rational Expectations  

NSDL National Science Digital Library

Rational Expectations was set up by Ralph Lazar, former strategist and economist for Goldman Sachs, Barings & Credit Suisse First Boston, as a "resource for anyone interested in [emerging markets] economics -- students, teachers, lecturers, journalists, professionals, or just the curious." A fully comprehensive guide to the people, places, and events of the economics world, Rational Expectations includes an searchable database of over 1,000 organizations and institutions in OECD countries and emerging markets, a conference calendar, and job listings. The site also links to academic, professional, and government organizations, as well as a huge suggested publication list and macroeconomic and financial market data. Rational Expectations will be a welcome resource for anyone interested in emerging markets economics.

Lazar, Ralph.

111

Expected Value  

NSDL National Science Digital Library

In this activity, students will use the random integer command on their graphing calculators to simulate rolling a die. They will then use operations on lists to analyze the probability of rolling the first 1 on the 1st roll, 2nd roll, and so on and finally find the expected value. Teacher notes explain in detail how to perform these actions on the graphing calculator.

2008-10-17

112

Maximization, learning, and economic behavior.  

PubMed

The rationality assumption that underlies mainstream economic theory has proved to be a useful approximation, despite the fact that systematic violations to its predictions can be found. That is, the assumption of rational behavior is useful in understanding the ways in which many successful economic institutions function, although it is also true that actual human behavior falls systematically short of perfect rationality. We consider a possible explanation of this apparent inconsistency, suggesting that mechanisms that rest on the rationality assumption are likely to be successful when they create an environment in which the behavior they try to facilitate leads to the best payoff for all agents on average, and most of the time. Review of basic learning research suggests that, under these conditions, people quickly learn to maximize expected return. This review also shows that there are many situations in which experience does not increase maximization. In many cases, experience leads people to underweight rare events. In addition, the current paper suggests that it is convenient to distinguish between two behavioral approaches to improve economic analyses. The first, and more conventional approach among behavioral economists and psychologists interested in judgment and decision making, highlights violations of the rational model and proposes descriptive models that capture these violations. The second approach studies human learning to clarify the conditions under which people quickly learn to maximize expected return. The current review highlights one set of conditions of this type and shows how the understanding of these conditions can facilitate market design. PMID:25024182

Erev, Ido; Roth, Alvin E

2014-07-22

113

Noncommutative maximal ergodic theorems  

Microsoft Academic Search

This paper is devoted to the study of various maximal ergodic theorems in noncommutative $L_p$-spaces. In particular, we prove the noncommutative analogue of the classical Dunford-Schwartz maximal ergodic inequality for positive contractions on $L_p$ and the analogue of Stein's maximal inequality for symmetric positive contractions. We also obtain the corresponding individual ergodic theorems. We apply these results to a family

Marius Junge; Quanhua Xu

2005-01-01

114

Maxims for Mentoring.  

ERIC Educational Resources Information Center

This paper describes five maxims for an effective faculty mentoring program developed at Western Carolina University (North Carolina) designed to increase retention of new faculty. The first maxim, "ask what the program will do for the school," emphasizes that a program should not be undertaken until this question has been specifically and…

Kirk, James J.

115

Inclusive fitness maximization: An axiomatic approach.  

PubMed

Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of quasi-inclusive fitness maximization can be derived from axioms on an individual?s 'as if preferences' (binary choices) for the case in which phenotypic effects are additive. Our results help integrate evolutionary theory and rational choice theory, help draw out the behavioural implications of inclusive fitness maximization, and point to a possible way in which evolution could lead organisms to implement it. PMID:24530825

Okasha, Samir; Weymark, John A; Bossert, Walter

2014-06-01

116

MAXIM science and technology  

NASA Astrophysics Data System (ADS)

The Micro Arcsecond X-ray Imaging Mission (MAXIM) has been proposed to NASA in response to the Black Hole Imager line in the newly created "Beyond Einstein" program. Meeting the scientific goals of event horizon imaging has created a new set of technical challenges for the Maxim team. Certainly the most difficult of these is the need for 0.1 micro-arcsecond resolution imaging in the x-ray. We will review the key scientific challenges and show how they flow down into instrument requirements. We will then review our baseline design, discuss the array of technical challenges facing Maxim, and present the current status of our technology.

Cash, Webster C.; Gendreau, Keith C.

2004-10-01

117

Subjective Probability and Expected Utility without Additivity  

Microsoft Academic Search

An act maps states of nature to outcomes: deterministic outcomes, as well as random outcomes, are included. Two acts f and g are comonotonic, by definition, if it never happens that f(s) > f(t) and g(t) > g(s) for some states of nature s and t. An axiom of comonotonic independence is introduced here. It weakens the von Neumann-Morgenstern axiom

David Schmeidler

1989-01-01

118

Human Resources Maximization.  

ERIC Educational Resources Information Center

Discusses human resources maximization as a means for expanding employee selection criteria to include applicants' strengths and potential for growth, not just their history, then working to develop employees potential. Testing learning style as a means for recognizing potential and the relationship between testing and training are discussed. (KRN)

Grabb, Larry E.

1994-01-01

119

MAXIM: The Blackhole Imager  

NASA Technical Reports Server (NTRS)

The Beyond Einstein Program in NASA's Office of Space Science Structure and Evolution of the Universe theme spells out the top level scientific requirements for a Black Hole Imager in its strategic plan. The MAXIM mission will provide better than one tenth of a microarcsecond imaging in the X-ray band in order to satisfy these requirements. We will overview the driving requirements to achieve these goals and ultimately resolve the event horizon of a supermassive black hole. We will present the current status of this effort that includes a study of a baseline design as well as two alternative approaches.

Gendreau, Keith; Cash, Webster; Gorenstein, Paul; Windt, David; Kaaret, Phil; Reynolds, Chris

2004-01-01

120

Factors Affecting the Ability to Sustain Maximal Work  

Microsoft Academic Search

Purpose: The purpose of this investigation was to examine the ability to sustain a maximal running effort. Furthermore, the effects of aerobic fitness level, gender, anaerobic capacity, efficiency of energy production and utilization, and lactate threshold on maximal performance were examined.\\u000aMethods: Maximal oxygen consumption (VO2max), ventilatory threshold (VT) and anaerobic capacity (AC) were determined for 22 subjects. Subjects then

Miranda Kaye Undem

2010-01-01

121

Teachers' Maxims in Language Teaching.  

ERIC Educational Resources Information Center

Focuses on the nature and role of teaching principles. The article discusses the nature of teachers' maxims through analysis of teachers' accounts of their teaching and lesson protocols. Findings indicate that these maxims reflect cultural factors, belief systems, experience, and training. Understanding the importance and influence of these maxims

Richards, Jack C.

1996-01-01

122

Multidimensional Scaling for Measuring Alcohol Expectancies.  

ERIC Educational Resources Information Center

Although expectancies for alcohol have been shown to influence drinking behavior, current expectancy questionnaires do not lend themselves to the study of how expectancies are represented in memory. Two studies were conducted which utilized multidimensional scaling techniques designed to produce hypothesized representations of cognitive…

Rather, Bruce; And Others

123

Cardiovascular pharmacogenomics: expectations and practical benefits.  

PubMed

Cardiovascular disease is a leading cause of morbidity and mortality worldwide. Pharmacogenomics is the study of genetic determinants of interindividual variation in drug response and aims to facilitate personalized medicine, through genotype-informed drug and dose selection, to maximize drug efficacy and/or minimize adverse drug reactions. Despite high expectations, no cardiovascular pharmacogenomic association is currently in widespread clinical practice; evidential, logistical, financial, and knowledge implementation barriers exist. Nevertheless, VKORC1, CYP2C9, and CYP4F2 variants have been associated with warfarin dose requirements, and CYP2C19 variants have been associated with perturbed antiplatelet response to clopidogrel. However, at present, controversy exists over the clinical utility of these genetic associations. There is an increased risk of simvastatin-induced muscle toxicity in SLCO1B1*5 carriers, ADRB1 and ADRA2C polymorphisms are associated with differential response to bucindolol, and rare congenital arrhythmia gene variants have been identified in drug-induced torsade de pointes. Practical benefits are still anticipated, but much work remains. PMID:24322971

Turner, R M; Pirmohamed, M

2014-03-01

124

Maximizing relationship possibilities: relational maximization in romantic relationships.  

PubMed

Using Rusbult's (1980) investment model and Schwartz's (2000) conceptualization of decision maximization, we sought to understand how an individual's propensity to maximize his or her decisions factored into investment, satisfaction, and awareness of alternatives in romantic relationships. In study one, 275 participants currently involved in romantic relationships completed measures of maximization, satisfaction, investment size, quality of alternatives, and commitment. In study two, 343 participants were surveyed as part of the creation of a scale of relational maximization. Results from both studies revealed that the tendency to maximize (in general and in relationships specifically) was negatively correlated with satisfaction, investment, and commitment, and positively correlated with quality of alternatives. Furthermore, we found that satisfaction and investments mediated the relationship between maximization and relationship commitment. PMID:23951952

Mikkelson, Alan C; Pauley, Perry M

2013-01-01

125

Expecting the Best  

ERIC Educational Resources Information Center

Educational expectations are psychological constructs that change over time and can be altered or influenced by various factors. The concept of educational expectations refers to how much schooling students realistically believe that they will complete. These expectations are eventually raised or lowered as students see others like themselves…

DiPaula, John

2010-01-01

126

Do juries meet our expectations?  

PubMed

Surveys of public opinion indicate that people have high expectations for juries. When it comes to serious crimes, most people want errors of convicting the innocent (false positives) or acquitting the guilty (false negatives) to fall well below 10%. Using expected utility theory, Bayes' Theorem, signal detection theory, and empirical evidence from detection studies of medical decision making, eyewitness testimony, and weather forecasting, we argue that the frequency of mistakes probably far exceeds these "tolerable" levels. We are not arguing against the use of juries. Rather, we point out that a closer look at jury decisions reveals a serious gap between what we expect from juries and what probably occurs. When deciding issues of guilt and/or punishing convicted criminals, we as a society should recognize and acknowledge the abundance of error. PMID:12508698

Arkes, Hal R; Mellers, Barbara A

2002-12-01

127

Prescription stimulant expectancies in recreational and medical users: results from a preliminary expectancy questionnaire.  

PubMed

Given the rise of prescription stimulant misuse, examination of effect expectancies could prove helpful. The Prescription Stimulant Expectancy Questionnaire (PSEQ) was designed to explore positive and negative prescription stimulant-related expectancies. In 2006, 157 participants nationwide completed an Internet survey of prescription stimulant use, attention-deficit/hyperactivity disorder symptoms, and expectancies. Multiple regressions demonstrate that positive, but not negative expectancies, predicted frequency of use. Recreational and medical users were classified by hierarchical cluster analysis. Recreational users reported fewer positive and negative expectancies than medical users. Implications and limitations are discussed. Future research is warranted on prescription stimulant expectancies and the utility of the PSEQ. PMID:19938932

Looby, Alison; Earleywine, Mitch

2009-01-01

128

Maxims in Child Custody Cases  

ERIC Educational Resources Information Center

The author describes six maxims which are an outgrowth of his experience as an expert witness in cases involving child custody. He emphasizes neutrality regarding the parents, in order to put the child's interests first. (Author)

Jenkins, Richard L.

1977-01-01

129

Maximizing biodiversity, information and sustainability  

Microsoft Academic Search

Numerous global changes—notably anthropogenic extinction—force reconsideration of our management practices and the ways we\\u000a regulate human influence in today’s world. Here, I define management to maximize biodiversity and illustrate the science that\\u000a provides information to set goals for such management. Maximizing biodiversity simultaneously achieves sustainability and\\u000a systemic health by avoiding the abnormal or pathological. The normal or sustainable are determined

Charles W. Fowler

2008-01-01

130

Expectancy Theory Modeling.  

National Technical Information Service (NTIS)

An objective of this effort was to reformulate expectancy theory in organizational behavior in objective terms and measurable concepts, employing sound multivariate models. Although a vast amount of literature in organizational behavior has been generated...

P. Horst

1982-01-01

131

Reward expectations in honeybees  

PubMed Central

The study of expectations of reward helps to understand rules controlling goal-directed behavior as well as decision making and planning. I shall review a series of recent studies focusing on how the food gathering behavior of honeybees depends upon reward expectations. These studies document that free-flying honeybees develop long-term expectations of reward and use them to regulate their investment of energy/time during foraging. Also, they present a laboratory procedure suitable for analysis of neural substrates of reward expectations in the honeybee brain. I discuss these findings in the context of individual and collective foraging, on the one hand, and neurobiology of learning and memory of reward.

2010-01-01

132

Asserting Performance Expectations.  

National Technical Information Service (NTIS)

Traditional techniques for performance analysis provide a means for extracting and analyzing raw performance information from applications. Users then reason about and compare this raw performance data to their performance expectations for important appli...

J. S. Vetter P. Worley

2002-01-01

133

Maximizing TDRS Command Load Lifetime  

NASA Technical Reports Server (NTRS)

The GNC software onboard ISS utilizes TORS command loads, and a simplistic model of TORS orbital motion to generate onboard TORS state vectors. Each TORS command load contains five "invariant" orbital elements which serve as inputs to the onboard propagation algorithm. These elements include semi-major axis, inclination, time of last ascending node crossing, right ascension of ascending node, and mean motion. Running parallel to the onboard software is the TORS Command Builder Tool application, located in the JSC Mission Control Center. The TORS Command Builder Tool is responsible for building the TORS command loads using a ground TORS state vector, mirroring the onboard propagation algorithm, and assessing the fidelity of current TORS command loads onboard ISS. The tool works by extracting a ground state vector at a given time from a current TORS ephemeris, and then calculating the corresponding "onboard" TORS state vector at the same time using the current onboard TORS command load. The tool then performs a comparison between these two vectors and displays the relative differences in the command builder tool GUI. If the RSS position difference between these two vectors exceeds the tolerable lim its, a new command load is built using the ground state vector and uplinked to ISS. A command load's lifetime is therefore defined as the time from when a command load is built to the time the RSS position difference exceeds the tolerable limit. From the outset of TORS command load operations (STS-98), command load lifetime was limited to approximately one week due to the simplicity of both the onboard propagation algorithm, and the algorithm used by the command builder tool to generate the invariant orbital elements. It was soon desired to extend command load lifetime in order to minimize potential risk due to frequent ISS commanding. Initial studies indicated that command load lifetime was most sensitive to changes in mean motion. Finding a suitable value for mean motion was therefore the key to achieving this goal. This goal was eventually realized through development of an Excel spreadsheet tool called EMMIE (Excel Mean Motion Interactive Estimation). EMMIE utilizes ground ephemeris nodal data to perform a least-squares fit to inferred mean anomaly as a function of time, thus generating an initial estimate for mean motion. This mean motion in turn drives a plot of estimated downtrack position difference versus time. The user can then manually iterate the mean motion, and determine an optimal value that will maximize command load lifetime. Once this optimal value is determined, the mean motion initially calculated by the command builder tool is overwritten with the new optimal value, and the command load is built for uplink to ISS. EMMIE also provides the capability for command load lifetime to be tracked through multiple TORS ephemeris updates. Using EMMIE, TORS command load lifetimes of approximately 30 days have been achieved.

Brown, Aaron J.

2002-01-01

134

Do Speakers and Listeners Observe the Gricean Maxim of Quantity?  

ERIC Educational Resources Information Center

The Gricean Maxim of Quantity is believed to govern linguistic performance. Speakers are assumed to provide as much information as required for referent identification and no more, and listeners are believed to expect unambiguous but concise descriptions. In three experiments we examined the extent to which naive participants are sensitive to the…

Engelhardt, Paul E.; Bailey, Karl G. D.; Ferreira, Fernanda

2006-01-01

135

Maximal acceleration, Mach's principle, and the mass of the electron  

Microsoft Academic Search

Recent arguments for an upper limit to the proper acceleration of extended massive bodies are briefly reviewed. A transient mass shift in accelerated objects with non-constant proper mass density, expected in all locally Lorentz-invariant theories of gravitation which satisfy Mach's principle, is considered. This effect affects arguments for a maximal proper acceleration. It is shown that, while the widely discussed

James F. Woodward

1993-01-01

136

Expected Performance Centering for Analog\\/RF Designs  

Microsoft Academic Search

We unite the conventional analog\\/RF design objectives such as design centering and performance targeting and propose a generalized analog\\/RF design objective. We propose expected performance centering, i.e., to maximize the expected performance margin of a circuit under process and environmental variations for topology selection with performance specification in a hierarchical design. We develop three methods to compute expected performance margin.

Bao Liu; Andrew B. Kahng

2006-01-01

137

Performance expectation plan  

SciTech Connect

This document outlines the significant accomplishments of fiscal year 1998 for the Tank Waste Remediation System (TWRS) Project Hanford Management Contract (PHMC) team. Opportunities for improvement to better meet some performance expectations have been identified. The PHMC has performed at an excellent level in administration of leadership, planning, and technical direction. The contractor has met and made notable improvement of attaining customer satisfaction in mission execution. This document includes the team`s recommendation that the PHMC TWRS Performance Expectation Plan evaluation rating for fiscal year 1998 be an Excellent.

Ray, P.E.

1998-09-04

138

Hostility, Maximization, & the Public Trust.  

ERIC Educational Resources Information Center

Ideas from current economic theory are applied to the nation's attitudes toward higher education. Ideas about asymmetric market information, trust markets, nonprofit firms, and maximization on campus are discussed. Public relations problems concerning accounting, deficits, and interest arbitrage are identified. The need for increased efficiency…

Winston, Gordon C.

1992-01-01

139

An inflation expectations horserace  

Microsoft Academic Search

For decades, the academic literature has focused on three survey measures of expected inflation: the Livingston Survey, the Survey of Professional Forecasters, and the Michigan Survey. While these measures have been useful in developing models of forecasting inflation, the data are low frequency measures which appear anachronistic in the modern era of high frequency and real-time data. I present a

Giselle C. Guzman

2009-01-01

140

It's To Be Expected  

NSDL National Science Digital Library

In this activity, students use a tree diagram on their graphing calculators to find theoretical probabilities. They then manipulate this information in a spreadsheet to find the expected value. This lesson includes teacher notes, a student worksheet with solutions, and a homework assignment with solutions.

2010-08-27

141

Reserve selection as a maximal covering location problem  

Microsoft Academic Search

Many alternative approaches have been proposed for setting conservation priorities from a database of species (or communities) by site. We present a model based on the premise that reserve selection or site prioritization can be structured as a classic covering problem commonly used in many location problems. Specifically, we utilize a form of the maximal covering location model to identify

Richard L. Church; David M. Stoms; Frank W. Davis

1996-01-01

142

Maximizing efficiency of solar-powered systems by load matching  

Microsoft Academic Search

Solar power is an important source of renewable energy for many low-power systems. Matching the power consumption level with the supply level can make a great difference in the efficiency of power utilization. This paper proposes a source-tracking power management strategy that maximizes the panel's total energy output under a given solar profile by load matching. The power efficiency was

Dexin Li; Pai H. Chou

2004-01-01

143

Learning to maximize reward rate: a model based on semi-Markov decision processes  

PubMed Central

When animals have to make a number of decisions during a limited time interval, they face a fundamental problem: how much time they should spend on each decision in order to achieve the maximum possible total outcome. Deliberating more on one decision usually leads to more outcome but less time will remain for other decisions. In the framework of sequential sampling models, the question is how animals learn to set their decision threshold such that the total expected outcome achieved during a limited time is maximized. The aim of this paper is to provide a theoretical framework for answering this question. To this end, we consider an experimental design in which each trial can come from one of the several possible “conditions.” A condition specifies the difficulty of the trial, the reward, the penalty and so on. We show that to maximize the expected reward during a limited time, the subject should set a separate value of decision threshold for each condition. We propose a model of learning the optimal value of decision thresholds based on the theory of semi-Markov decision processes (SMDP). In our model, the experimental environment is modeled as an SMDP with each “condition” being a “state” and the value of decision thresholds being the “actions” taken in those states. The problem of finding the optimal decision thresholds then is cast as the stochastic optimal control problem of taking actions in each state in the corresponding SMDP such that the average reward rate is maximized. Our model utilizes a biologically plausible learning algorithm to solve this problem. The simulation results show that at the beginning of learning the model choses high values of decision threshold which lead to sub-optimal performance. With experience, however, the model learns to lower the value of decision thresholds till finally it finds the optimal values.

Khodadadi, Arash; Fakhari, Pegah; Busemeyer, Jerome R.

2014-01-01

144

Is the beta phase maximal?  

SciTech Connect

indicates that 2|Vub / Vcb/ Vus| = (1-z) with z given by z = 0.19 +(-) 0.14. This fact implies that irrespective of the form of the quark Yukawa matrices, the measured value of the SM CP phase beta is approximately the maximum allowed by the measured absolute values of the CKM elements. This is beta = pi/6 - z/sqrt{3} for gamma = pi/3 + z/sqrt{3}, which implies alpha = pi/2. Alternatively, assuming that beta is exactly maximal and using the experimental measurement, sin(2beta) = 0.726+(-) 0.037, the phase gamma is predicted to be gamma = pi/2 - beta = 66.3 +(-) 1.7. The maximality of beta, if confirmed by the near-future experiments, may give us some clues as to the origin of CP violation.

Ferrandis, Javier; Ferrandis, Javier

2005-04-20

145

Genetic enhancements and expectations.  

PubMed

Some argue that genetic enhancements and environmental enhancements are not importantly different: environmental enhancements such as private schools and chess lessons are simply the old-school way to have a designer baby. I argue that there is an important distinction between the two practices--a distinction that makes state restrictions on genetic enhancements more justifiable than state restrictions on environmental enhancements. The difference is that parents have no settled expectations about genetic enhancements. PMID:19567693

Sorensen, K

2009-07-01

146

Ageing and maximal physical performance  

Microsoft Academic Search

Elite master athletes with long-term devotion to physical training offer an economical means of investigating the effects\\u000a of ageing and habitual exercise on maximal physical performance. Ideally, individuals with optimised living habits throughout\\u000a their lives could serve as a human model of ‘primary’ or ‘inherent’ ageing, where age-related changes are not confounded by\\u000a sedentary life-style and associated chronic diseases. A

Harri Suominen

2011-01-01

147

Downside Consumption Risk and Expected Returns  

Microsoft Academic Search

I derive and test empirically the implications of a consumption asset pricing model based on a first-order risk averse utility which allows for distinct aversion to downturns in consumption. The model nests the standard expected-utility-based CCAPM as a special case and is estimated using Fama-French portfolios. In the empirical speci- fication the model is stated in a two factor form

Valery Polkovnichenko

148

A row-action alternative to the EM algorithm for maximizing likelihood in emission tomography  

Microsoft Academic Search

The maximum likelihood (ML) approach to estimating the radioactive distribution in the body cross section has become very popular among researchers in emission computed tomography (ECT) since it has been shown to provide very good images compared to those produced with the conventional filtered backprojection (FBP) algorithm. The expectation maximization (EM) algorithm is an often-used iterative approach for maximizing the

Jolyon Browne; Alvaro R. De Pierro

1996-01-01

149

MAXIM: the black hole imager  

NASA Astrophysics Data System (ADS)

The Beyond Einstein Program in NASA"s Office of Space Science Structure and Evolution of the Universe theme spells out the top level scientific requirements for a Black Hole Imager in its strategic plan. The MAXIM mission will provide better than one tenth of a microarcsecond imaging in the X-ray band in order to satisfy these requirements. We will overview the driving requirements to achieve these goals and ultimately resolve the event horizon of a supermassive black hole. We will present the current status of this effort that includes a study of a baseline design as well as two alternative approaches

Gendreau, Keith C.; Cash, Webster C.; Gorenstein, Paul; Windt, David L.; Kaaret, Phil; Reynolds, Chris

2004-10-01

150

An Activity for Exploring Marital Expectations  

ERIC Educational Resources Information Center

The learning activity, designed for the use of high school students in a family life education course, is designed to explore attitudes towards mate qualities in order to increase the students' awareness of marital expectations. The activity utilizes the format of an auction game and a group discussion. (EC)

Saur, William G.

1976-01-01

151

An Accountability Approach Using Expectancy Criteria.  

ERIC Educational Resources Information Center

If American schools are to be held accountable for pupil achievement, a reliable means of determining the difference between a child's actual achievement and his learning potential must be found. This study examines the utilization of composite measures of a pupil's base level of performance as effective predictors of learning expectancy. In…

Metos, Thomas H.; Luty, Elanny T.

152

Cerebral palsy life expectancy.  

PubMed

The life expectancy of people who have perinatally acquired cerebral palsy can be similar to that of the general population, or it can be reduced substantially. The most important factors that are associated with reduced survival are disabilities of motor, cognitive, or visual functions. Prematurity and low birth weight are associated with lower rates of disability, and better survival. A 2-year-old who has severe cerebral palsy has about a 40% chance of living to age 20, in contrast to a child who has mild cerebral palsy, for whom the chance is 99%. Cerebral palsy, respiratory diseases, epilepsy, and congenital malformation are the most commonly recorded causes of early death. PMID:16765736

Hutton, Jane L

2006-06-01

153

Fast regularization technique for expectation maximization algorithm for optical sectioning microscopy  

NASA Astrophysics Data System (ADS)

Maximum likelihood image restoration is a powerful method for 3D computational optical sectioning microscopy of extended objects. With punctate specimens, however, this method produces a few very bright isolated spots and dim detail around them is lost. The commonly used regularization methods (sieves and roughness penalty) decrease the amplitude of the bright spots, but do not avoid loosing dim detail. We derived an intensity regularization that decreases the amplitude of bright spots without loosing dim detail. In contrast with other regularization methods, this method does not increase significantly the computational complexity of the estimation algorithm.

Conchello, Jose-Angel; McNally, James G.

1996-04-01

154

Gene Regulatory Network Construction Using Dynamic Bayesian Network (DBN) with Structure Expectation Maximization (SEM)  

Microsoft Academic Search

Discovering gene relationship from gene expression data is a hot topic in the post-genomic era. In recent years, Bayesian\\u000a network has become a popular method to reconstruct the gene regulatory network due to the statistical nature. However, it\\u000a is not suitable for analyzing the time-series data and cannot deal with cycles in the gene regulatory network. In this paper\\u000a we

Yu Zhang; Zhidong Deng; Hongshan Jiang; Peifa Jia

2006-01-01

155

Expectation maximization algorithms for MAP estimation of jump Markov linear systems  

Microsoft Academic Search

In a jump Markov linear system, the state matrix, observation matrix, and the noise covariance matrices evolve according to the realization of a finite state Markov chain. Given a realization of the observation process, the aim is to estimate the state of the Markov chain assuming known model parameters. Computing conditional mean estimates is infeasible as it involves a cost

Andrew Logothetis; Vikram Krishnamurthy

1999-01-01

156

Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization.  

National Technical Information Service (NTIS)

This research effort explores and develops a real-time sonar-based robot mapping and localization algorithm that provides pose correction within the context of a singe room, to be combined with pre-existing global localization techniques, and thus produce...

K. L. Owens

2005-01-01

157

Treatment Options in Alzheimer’s Disease: Maximizing Benefit, Managing Expectations  

Microsoft Academic Search

Alzheimer’s disease (AD) is becoming an increasingly heavy burden on the society of developed countries, and physicians now face the challenge of providing efficient treatment regimens to an ever-higher number of individuals affected by the disease. Currently approved anti-AD therapies – the cholinesterase inhibitors and the N-methyl-D-aspartate receptor antagonist memantine – offer modest symptomatic relief, which can be enhanced using

Martin R. Farlow; Michael L. Miller; Vojislav Pejovic

2008-01-01

158

Feature Normalization via Expectation Maximization and Unsupervised Nonparametric Classification For M-FISH Chromosome Images  

Microsoft Academic Search

Multicolor fluorescence in situ hybridization (M-FISH) techniques provide color karyotyping that allows simultaneous analysis of numerical and structural abnormalities of whole human chromosomes. Chromosomes are stained combinatorially in M-FISH. By analyzing the intensity combinations of each pixel, all chromosome pixels in an image are classified. Often, the intensity distributions between different images are found to be considerably different and the

Hyohoon Choi; Alan C. Bovik; Kenneth R. Castleman

2008-01-01

159

Imaging a black hole: MAXIM  

NASA Astrophysics Data System (ADS)

With the general acceptance of black holes as real entities the astrophysics community has turned its attention to studying their behavior and properties. Because of the great distance and compact size of the central engine, astronomers are limited to spectroscopic analysis. But to take a picture, or better yet a movie, of the black hole in silhouette against its accretion disk would be a triumph of exploration and scientific inquiry. Probing to the event horizon is best accomplished in the X-ray band, where material primarily radiates in the last orbits before its final plunge. Not only will the signal be bright and minimally confused in the X-ray, but the size of the required interferometer drops dramatically. We describe MAXIM, the Micro-Arcsecond X-ray Imaging Mission, which is now being studied and developed by NASA. We will explain the preliminary mission concept which will use currently existing technology to achieve spatial resolution one million times higher than that of the Hubble Space Telescope and capture the image of an event horizon in a nearby Active Galactic Nucleus. We will also describe the MAXIM Pathfinder. Designed as a stepping stone at resolution of 100 micro-arcseconds, it will demonstrate the techniques of X-ray interferometry and perform groundbreaking science like resolving the coronae of the nearby stars.

Cash, W.

160

Knowledge discovery by accuracy maximization.  

PubMed

Here we describe KODAMA (knowledge discovery by accuracy maximization), an unsupervised and semisupervised learning algorithm that performs feature extraction from noisy and high-dimensional data. Unlike other data mining methods, the peculiarity of KODAMA is that it is driven by an integrated procedure of cross-validation of the results. The discovery of a local manifold's topology is led by a classifier through a Monte Carlo procedure of maximization of cross-validated predictive accuracy. Briefly, our approach differs from previous methods in that it has an integrated procedure of validation of the results. In this way, the method ensures the highest robustness of the obtained solution. This robustness is demonstrated on experimental datasets of gene expression and metabolomics, where KODAMA compares favorably with other existing feature extraction methods. KODAMA is then applied to an astronomical dataset, revealing unexpected features. Interesting and not easily predictable features are also found in the analysis of the State of the Union speeches by American presidents: KODAMA reveals an abrupt linguistic transition sharply separating all post-Reagan from all pre-Reagan speeches. The transition occurs during Reagan's presidency and not from its beginning. PMID:24706821

Cacciatore, Stefano; Luchinat, Claudio; Tenori, Leonardo

2014-04-01

161

Quantization via Empirical Divergence Maximization  

NASA Astrophysics Data System (ADS)

Empirical divergence maximization (EDM) refers to a recently proposed strategy for estimating f-divergences and likelihood ratio functions. This paper extends the idea to empirical vector quantization where one seeks to empirically derive quantization rules that maximize the Kullback-Leibler divergence between two statistical hypotheses. We analyze the estimator's error convergence rate leveraging Tsybakov's margin condition and show that rates as fast as 1/n are possible, where n equals the number of training samples. We also show that the Flynn and Gray algorithm can be used to efficiently compute EDM estimates and show that they can be efficiently and accurately represented by recursive dyadic partitions. The EDM formulation have several advantages. First, the formulation gives access to the tools and results of empirical process theory that quantify the estimator's error convergence rate. Second, the formulation provides a previously unknown derivation for the Flynn and Gray algorithm. Third, the flexibility it affords allows one to avoid a small-cell assumption common in other approaches. Finally, we illustrate the potential use of the method through an example.

Lexa, Michael A.

2012-12-01

162

Ventromedial frontal lobe damage disrupts value maximization in humans.  

PubMed

Recent work in neuroeconomics has shown that regions in orbitofrontal and medial prefrontal cortex encode the subjective value of different options during choice. However, these electrophysiological and neuroimaging studies cannot demonstrate whether such signals are necessary for value-maximizing choices. Here we used a paradigm developed in experimental economics to empirically measure and quantify violations of utility theory in humans with damage to the ventromedial frontal lobe (VMF). We show that people with such damage are more likely to make choices that violate the generalized axiom of revealed preference, which is the one necessary and sufficient condition for choices to be consistent with value maximization. These results demonstrate that the VMF plays a critical role in value-maximizing choice. PMID:21593337

Camille, Nathalie; Griffiths, Cathryn A; Vo, Khoi; Fellows, Lesley K; Kable, Joseph W

2011-05-18

163

Ventromedial frontal lobe damage disrupts value maximization in humans  

PubMed Central

Recent work in neuroeconomics has shown that regions in orbitofrontal and medial prefrontal cortex encode the subjective value of different options during choice. However, these electrophysiological and neuroimaging studies cannot demonstrate whether such signals are necessary for value-maximizing choices. Here we used a paradigm developed in experimental economics to empirically measure and quantify violations of utility theory in humans with damage to the ventromedial frontal lobe (VMF). We show that people with such damage are more likely to make choices that violate the generalized axiom of revealed preference, which is the one necessary and sufficient condition for choices to be consistent with value maximization. These results demonstrate that the VMF plays a critical role in value-maximizing choice.

Camille, Nathalie; Griffiths, Cathryn A.; Vo, Khoi; Fellows, Lesley K.; Kable, Joseph W.

2011-01-01

164

A comparative study of expectant parents ' childbirth expectations.  

PubMed

The purpose of this study was to understand childbirth expectations and differences in childbirth expectations among expectant parents. For convenience sampling, 200 couples willing to participate in this study were chosen from two hospitals in central Taiwan. Inclusion criteria were at least 36 weeks of gestation, aged 18 and above, no prenatal complications, and willing to consent to participate in this study. Instruments used to collect data included basic demographic data and the Childbirth Expectations Questionnaire. Findings of the study revealed that (1) five factors were identified by expectant parents regarding childbirth expectations including the caregiving environment, expectation of labor pain, spousal support, control and participation, and medical and nursing support; (2) no general differences were identified in the childbirth expectations between expectant fathers and expectant mothers; and (3) expectant fathers with a higher socioeconomic status and who had received prenatal (childbirth) education had higher childbirth expectations, whereas mothers displayed no differences in demographic characteristics. The study results may help clinical healthcare providers better understand differences in expectations during labor and birth and childbirth expectations by expectant parents in order to improve the medical and nursing system and promote positive childbirth experiences and satisfaction for expectant parents. PMID:15362011

Kao, Bi-Chin; Gau, Meei-Ling; Wu, Shian-Feng; Kuo, Bih-Jaw; Lee, Tsorng-Yeh

2004-09-01

165

Dynamics in maximal settling capacity in an activated sludge treatment plant with highly loaded secondary settlers  

Microsoft Academic Search

Secondary settling dynamics at maximal capacity were investigated at a full scale wastewater treatment plant which utilizes a unique process solution incorporating pre-denitrification with post- nitrification in nitrifying trickling filters. Since nitrogen removal is greater when more secondary effluent is recirculated to the trickling filters, the secondary settlers generally operate at close to their maximal capacity. The settling and flocculation

B.-M. Wilén; D. Lumley; A. Nordqvist

2004-01-01

166

New standard exceeds expectations  

SciTech Connect

The new ASTM environmental due diligence standard is delivering far more than expected when it was conceived in 1990. Its use goes well beyond the relatively narrow legal liability protection that was the primary goal in its development. The real estate industry, spearheaded by the lending community, was preoccupied with environmental risk and liability. Lenders throughout the concept's evolution have been at the forefront in defining environmental due diligence. The lender liability rule is intended to protect property owners from CERCLA liability for property they own or companies they manage (for example, as a result of foreclosure). The new site assessment standard increasingly is considered a benchmark for prudent environmental due diligence in the interest of risk management, not legal liability. The focus on risk management, including collateral devaluation and corporate credit risk, are becoming dominant areas of policy focus in the lending industry. Lenders now are revising their policies to incorporate transactions beyond issues of real estate, in which a company's economic viability and ability to service debt could be impacted by an environmental problem unrelated to property transfers.

Bennett, M.J. (Environmental Data Resources Inc., Southport, CT (United States))

1993-08-01

167

Lighting spectrum to maximize colorfulness.  

PubMed

The spectrum of modern illumination can be computationally tailored considering the visual effects of lighting. We investigated the spectral profiles of the white illumination maximizing the theoretical limits of the perceivable object colors. A large number of metamers with various degrees of smoothness were generated on and around the Planckian locus, and the volume in the CIELAB space of the optimal colors for each metamer was calculated. The optimal spectrum was found at the color temperature of around 5.7×10(3) K, had three peaks at both ends of the visible band and at around 510 nm, and was 25% better than daylight and 35% better than Thornton's prime color lamp. PMID:22297368

Masuda, Osamu; Nascimento, Sérgio M C

2012-02-01

168

Optimized expected information gain for nonlinear dynamical systems  

Microsoft Academic Search

This paper addresses the problem of active model selection for nonlinear dynamical systems. We propose a novel learning approach that selects the most informative subset of time-dependent variables for the purpose of Bayesian model inference. The model selection criterion maximizes the expected Kullback-Leibler divergence between the prior and the posterior probabilities over the models. The proposed strategy generalizes the standard

Alberto Giovanni Busetto; Cheng Soon Ong; Joachim M. Buhmann

2009-01-01

169

The Learning Styles, Expectations, and Needs of Online Students  

ERIC Educational Resources Information Center

Each student comes to class with certain learning experiences, expectations, and needs that have to be addressed, and to which instructors need to be sensitive, to maximize the students' learning experiences. However, because of the unknown make-up of online classes, the characteristics of online students may be unclear, making it difficult to…

Mupinga, Davison M.; Nora, Robert T.; Yaw, Dorothy Carole

2006-01-01

170

Binary Choice Probabilities Between Gambles: Interlocking Expected Utility Models.  

National Technical Information Service (NTIS)

This report discusses two models for describing an individual's binary choice probabilities between gambles whose outcomes are measured along a unidimensional scale on which a larger outcome is preferred to a smaller outcome. The models presume an underly...

P. C. Fishburn

1975-01-01

171

Utilizing Alcohol Expectancies in the Treatment of Alcoholism.  

ERIC Educational Resources Information Center

The heterogeneity of alcoholic populations may be one reason that few specific therapeutic approaches to the treatment of alcoholism have been consistently demonstrated to improve treatment outome across studies. To individualize alcoholism treatment, dimensions which are linked to drinking or relapse and along which alcoholics display significant…

Brown, Sandra A.

172

Economical Active Feature-value Acquisition through Expected Utility Estimation  

Microsoft Academic Search

In many classification tasks training data have missing feature val- ues that can be acquired at a cost. For building accurate predictive models, acquiring all missing values is often prohibitively expen- sive or unnecessary, while acquiring a random subset of feature values may not be most effective. The goal of active feature-value acquisition is to incrementally select feature values that

Prem Melville; Maytal Saar-Tsechansky; Raymond Mooney

2004-01-01

173

An Expected Utility Approach to Active Feature-Value Acquisition  

Microsoft Academic Search

In many classification tasks training data have missing feature values that can be acquired at a cost. For build- ing accurate predictive models, acquiring all missing val- ues is often prohibitively expensive or unnecessary, while acquiring a random subset of feature values may not be most effective. The goal of active feature-value acquisition is to incrementally select feature values that

Prem Melville; Foster J. Provost; Raymond J. Mooney

2005-01-01

174

Economical active feature-value acquisition through Expected Utility estimation  

Microsoft Academic Search

In many classification tasks training data have missing feature values that can be acquired at a cost. For building accurate predictive models, acquiring all missing values is often prohibitively expensive or unnecessary, while acquiring a random subset of feature values may not be most effective. The goal of active feature-value acquisition is to incrementally select feature values that are most

Prem Melville; Foster Provost; Maytal Saar-Tsechansky; Raymond Mooney

2005-01-01

175

Maximal Oxygen Intake and Maximal Work Performance of Active College Women.  

ERIC Educational Resources Information Center

Maximal oxygen intake and associated physiological variables were measured during strenuous exercise on women subjects (N=20 physical education majors). Following assessment of maximal oxygen intake, all subjects underwent a performance test at the work level which had elicited their maximal oxygen intake. Mean maximal oxygen intake was 41.32…

Higgs, Susanne L.

176

Expectancy and Expected Value: Decision Models for Organizations.  

National Technical Information Service (NTIS)

The development of Expectancy Theory and Expected Value models is reviewed. The research supporting these models in the areas of decision making, leadership attitudes, motivation and social power is discussed. The final section provides insights into the ...

T. R. Mitchell

1976-01-01

177

Expecting ourselves to expect: the Bayesian brain as a projector.  

PubMed

Clark's essay lays the foundation for a Bayesian account of the "projection" of consciously perceived properties: The expectations that our brains test against inputs concern the particular affordances that evolution has designed us to care about, including especially expectations of our own expectations. PMID:23663550

Dennett, Daniel C

2013-06-01

178

Great Expectations: Temporal Expectation Modulates Perceptual Processing Speed  

ERIC Educational Resources Information Center

In a crowded dynamic world, temporal expectations guide our attention in time. Prior investigations have consistently demonstrated that temporal expectations speed motor behavior. We explore effects of temporal expectation on "perceptual" speed in three nonspeeded, cued recognition paradigms. Different hazard rate functions for the cue-stimulus…

Vangkilde, Signe; Coull, Jennifer T.; Bundesen, Claus

2012-01-01

179

A Maximally Supersymmetric Kondo Model  

SciTech Connect

We study the maximally supersymmetric Kondo model obtained by adding a fermionic impurity to N = 4 supersymmetric Yang-Mills theory. While the original Kondo problem describes a defect interacting with a free Fermi liquid of itinerant electrons, here the ambient theory is an interacting CFT, and this introduces qualitatively new features into the system. The model arises in string theory by considering the intersection of a stack of M D5-branes with a stack of N D3-branes, at a point in the D3 worldvolume. We analyze the theory holographically, and propose a dictionary between the Kondo problem and antisymmetric Wilson loops in N = 4 SYM. We perform an explicit calculation of the D5 fluctuations in the D3 geometry and determine the spectrum of defect operators. This establishes the stability of the Kondo fixed point together with its basic thermodynamic properties. Known supergravity solutions for Wilson loops allow us to go beyond the probe approximation: the D5s disappear and are replaced by three-form flux piercing a new topologically non-trivial S3 in the corrected geometry. This describes the Kondo model in terms of a geometric transition. A dual matrix model reflects the basic properties of the corrected gravity solution in its eigenvalue distribution.

Harrison, Sarah; Kachru, Shamit; Torroba, Gonzalo; /Stanford U., Phys. Dept. /SLAC

2012-02-17

180

Maximally Expressive Modeling of Operations Tasks  

NASA Technical Reports Server (NTRS)

Planning and scheduling systems organize "tasks" into a timeline or schedule. The tasks are defined within the scheduling system in logical containers called models. The dictionary might define a model of this type as "a system of things and relations satisfying a set of rules that, when applied to the things and relations, produce certainty about the tasks that are being modeled." One challenging domain for a planning and scheduling system is the operation of on-board experiments for the International Space Station. In these experiments, the equipment used is among the most complex hardware ever developed, the information sought is at the cutting edge of scientific endeavor, and the procedures are intricate and exacting. Scheduling is made more difficult by a scarcity of station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling International Space Station experiment operations calls for a "maximally expressive" modeling schema.

Jaap, John; Richardson, Lea; Davis, Elizabeth

2002-01-01

181

Utility-Optimal Random-Access Control  

Microsoft Academic Search

This paper designs medium access control (MAC) protocols for wireless networks through the network utility maximization (NUM) framework. A network-wide utility max- imization problem is formulated, using a collision\\/persistence- probabilistic model and aligning selfish utility with total social welfare. By adjusting the parameters in the utility objective functions of the NUM problem, we can also control the tradeoff between efficiency

Jang-won Lee; Mung Chiang; A. Robert Calderbank

2007-01-01

182

Measuring Alcohol Expectancies in Youth  

ERIC Educational Resources Information Center

Beliefs about the consequences of using alcohol, alcohol expectancies, are powerful predictors of underage drinking. The Alcohol Expectancies Questionnaire-Adolescent form (AEQ-A) has been widely used to measure expectancies in youth. Despite its broad use, the factor structure of the AEQ-A has not been firmly established. It is also not known…

Randolph, Karen A.; Gerend, Mary A.; Miller, Brenda A.

2006-01-01

183

Caffeinated Alcohol Use and Expectancies for Caffeine Versus Alcohol  

PubMed Central

Background Caffeinated alcoholic beverage (CAB) use is related to alcohol-related risk. Limited research has examined outcome expectancies and CAB consumption. Objectives This study tested the predictive utility of caffeine and alcohol expectancies in CAB use outcomes (i.e. quantity, frequency, and alcohol-related harms). Methods Participants were 419 (302 women) alcohol and caffeine users from a mid-sized urban university. Data collection occurred between August 2010 and December 2011. Participants completed measures of caffeine and alcohol expectancies, alcohol problems, alcohol use, and CAB use. Results Caffeine and alcohol expectancies contributed uniquely to approximately 12% of the variability in quantity, 8% in frequency, and 16% in problems. When examined separately, alcohol expectancies explained approximately 10% to 11% of the variance, whereas caffeine expectancies accounted for 6% of the variance in CAB use quantity. For CAB use frequency, alcohol and caffeine expectancies accounted for about 8% and 4%, respectively. Alcohol expectancies accounted for 12% to 14% of variance, whereas caffeine expectancies accounted for 4% to 6% in alcohol-related harms. Conclusions/Importance The present study sought to address a gap in the literature regarding the contributions of expectancies in the prediction of CAB use. Our findings provide support for the predictive utility of both caffeine and alcohol expectancies in accounting for individual variability in CAB use but alcohol expectancies may exert greater impact on use patterns. Inclusion of both types of expectancies in larger theoretical frameworks may be beneficial in gaining a more complete and deeper conceptualization of this risky behavior.

Lau-Barraco, Cathy; Linden, Ashley N.

2014-01-01

184

The Maximality of Unhygienic Dining Philosophers  

Microsoft Academic Search

The behaviors exhibited by a correct program are a subset of those allowed by its specification. A program is said to be maximal if, in addition to being correct, it can exh ibit any of the behaviors permitted by its specification. Maximality is useful for design, as it eliminates trivial or degenerate solutions; for performance as it requires solut ions

Matthew Lang; Paolo A. G. Sivilotti

185

Diurnal Variations in Maximal Oxygen Uptake.  

ERIC Educational Resources Information Center

A study attempted to determine if diurnal (daily cyclical) variations were present during maximal exercise. The subjects' (30 female undergraduate physical education majors) oxygen consumption and heart rates were monitored while they walked on a treadmill on which the grade was raised every minute. Each subject was tested for maximal oxygen…

McClellan, Powell D.

186

The futility of utility: how market dynamics marginalize Adam Smith  

NASA Astrophysics Data System (ADS)

Economic theorizing is based on the postulated, nonempiric notion of utility. Economists assume that prices, dynamics, and market equilibria are supposed to be derived from utility. The results are supposed to represent mathematically the stabilizing action of Adam Smith's invisible hand. In deterministic excess demand dynamics I show the following. A utility function generally does not exist mathematically due to nonintegrable dynamics when production/investment are accounted for, resolving Mirowski's thesis. Price as a function of demand does not exist mathematically either. All equilibria are unstable. I then explain how deterministic chaos can be distinguished from random noise at short times. In the generalization to liquid markets and finance theory described by stochastic excess demand dynamics, I also show the following. Market price distributions cannot be rescaled to describe price movements as ‘equilibrium’ fluctuations about a systematic drift in price. Utility maximization does not describe equilibrium. Maximization of the Gibbs entropy of the observed price distribution of an asset would describe equilibrium, if equilibrium could be achieved, but equilibrium does not describe real, liquid markets (stocks, bonds, foreign exchange). There are three inconsistent definitions of equilibrium used in economics and finance, only one of which is correct. Prices in unregulated free markets are unstable against both noise and rising or falling expectations: Adam Smith's stabilizing invisible hand does not exist, either in mathematical models of liquid market data, or in real market data.

McCauley, Joseph L.

2000-10-01

187

Measuring expectations: forecast vs. ideal expectations. Does it really matter?  

Microsoft Academic Search

Consumer's participation in service delivery is so central to cognition that it affects consumer's quality evaluations. The study presented in this paper investigates the ways that visitor expectations change as a result of first hand experience with a service in the context of a major art exhibition. The research design allowed for two operational definitions of expectations, namely forecast and

Bronwyn Higgs; Michael Jay Polonsky; Mary Hollick

2005-01-01

188

Expectancy bias in anxious samples.  

PubMed

Although it is well documented that anxious individuals have negative expectations about the future, it is unclear what cognitive processes give rise to this expectancy bias. Two studies are reported that use the Expectancy Task, which is designed to assess expectancy bias and illuminate its basis. This task presents individuals with valenced scenarios (Positive Valence, Negative Valence, or Conflicting Valence), and then evaluates their tendency to expect subsequent future positive relative to negative events. The Expectancy Task was used with low and high trait anxious (Study 1: n = 32) and anxiety sensitive (Study 2: n = 138) individuals. Results suggest that in the context of physical concerns, both high anxious samples display a less positive expectancy bias. In the context of social concerns, high trait anxious individuals display a negative expectancy bias only when negatively valenced information was previously presented. Overall, this suggests that anxious individuals display a less positive expectancy bias, and that the processes that give rise to this bias may vary by type of situation (e.g., social or physical) or anxiety difficulty. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24798678

Cabeleira, Cindy M; Steinman, Shari A; Burgess, Melissa M; Bucks, Romola S; MacLeod, Colin; Melo, Wilson; Teachman, Bethany A

2014-06-01

189

Educational Expectations and Attainment. NBER Working Paper No. 15683  

ERIC Educational Resources Information Center

This paper examines the role of educational expectations in the educational attainment process. We utilize data from a variety of datasets to document and analyze the trends in educational expectations between the mid-1970s and the early 2000s. We focus on differences across racial/ethnic and socioeconomic groups and examine how young people…

Jacob, Brian A.; Wilder, Tamara

2010-01-01

190

Sibling Status Effects: Adult Expectations.  

ERIC Educational Resources Information Center

This study attempted to determine what expectations or beliefs adults might hold about a child based on his or her sibling status alone. Ratings on 50 adjective pairs for each of three sibling status types, only, oldest, and youngest child, were assessed in relation to adult expectations, birth order, and parental status of rater. (Author/DST)

Baskett, Linda Musun

1985-01-01

191

Nobody expects the Spanish Inquistion  

NSDL National Science Digital Library

Is any one really ready for the Spanish Inquisition? Assign studnets to participate in reading the play, The Spanish Inquisition by Monty Python. While readiang the play, display the following pictures at appropiate times. Nobody expects the Spanish Inquistion Confess!!! Get the Cushions!!!! Get the comfy Chair! Now you'll confess! Confess women, CONFESS!!! Nobody expects the Spanish Inquisition!!! ...

Hirschi, Mrs.

2005-04-08

192

Are all maximally entangled states pure?  

SciTech Connect

We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of the monogamy of entanglement: we establish the polygamy of entanglement, expressing that if a general state is maximally entangled with respect to some kind of multipartite entanglement, then it is necessarily factorized of any other system.

Cavalcanti, D.; Brandao, F.G.S.L.; Terra Cunha, M.O. [Departamento de Fisica, Caixa Postal 702, Universidade Federal de Minas Gerais, 30123-970 Belo Horizonte, Minas Gerais (Brazil); Departamento de Matematica, Caixa Postal 702, Universidade Federal de Minas Gerais, 30123-970 Belo Horizonte, Minas Gerais (Brazil)

2005-10-15

193

Independent Component Analysis by Entropy Maximization (INFOMAX).  

National Technical Information Service (NTIS)

This thesis explores the 'Infomax' method of Independent Component Analysis (ICA) to accomplish blind source separation (BSS). The Infomax method separates unknown source signals from a number of signal mixtures by maximizing the entropy of a transformed ...

J. H. Garvey

2007-01-01

194

Associative Clustering by Maximizing a Bayes Factor.  

National Technical Information Service (NTIS)

Cluttering by maximizing the dependency between (margin) groupings or partitioning of co-occurring data pairs is studied. We suggest a probabilistic criterion that generalizes discriminative clustering (DC), an extension of the information bottleneck (IB)...

J. Sinkkonen J. Nikkilae L. Lahti S. Kaski

2003-01-01

195

Optimal sample size determinations from an industry perspective based on the expected value of information  

Microsoft Academic Search

Background Traditional sample size calculations for randomized clinical trials depend on somewhat arbitrarily chosen factors, such as type I and II errors. As an alternative, taking a societal perspective, and using the expected value of information based on Bayesian decision theory, a number of authors have recently shown how to determine the sample size that maximizes the expected net gain,

Andrew R Willan

2008-01-01

196

QM Position Expectation Value Program  

NSDL National Science Digital Library

The QM Position Expectation Value program displays the time evolution of the position-space wave function and the associated position expectation value. The default wave function is a two-state superposition of infinite square well states. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Position Expectation Value is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_expectation_x.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition.

Christian, Wolfgang

2008-04-17

197

QM Momentum Expectation Value Program  

NSDL National Science Digital Library

The QM Momentum Expectation Value program displays the time evolution of the position-space wave function and the associated momentum expectation value. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_expectation_p.jar file will run the program if Java is installed. The default wave function is a Gaussian wave packet in a harmonic oscillator. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Momentum Expectation Value is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition.

Christian, Wolfgang

2008-04-17

198

Formation Control of the MAXIM L2 Libration Orbit Mission  

NASA Technical Reports Server (NTRS)

The Micro-Arcsecond Imaging Mission (MAXIM), a proposed concept for the Structure and Evolution of the Universe (SEU) Black Hole Imaging mission, is designed to make a ten million-fold improvement in X-ray image clarity of celestial objects by providing better than 0.1 microarcsecond imaging. To achieve mission requirements, MAXIM will have to improve on pointing by orders of magnitude. This pointing requirement impacts the control and design of the formation. Currently the architecture is comprised of 25 spacecraft, which will form the sparse apertures of a grazing incidence X-ray interferometer covering the 0.3-10 keV bandpass. This configuration will deploy 24 spacecraft as optics modules and one as the detector. The formation must allow for long duration continuous science observations and also for reconfiguration that permits re-pointing of the formation. In this paper, we provide analysis and trades of several control efforts that are dependent upon the pointing requirements and the configuration and dimensions of the MAXIM formation. We emphasize the utilization of natural motions in the Lagrangian regions that minimize the control efforts and we address both continuous and discrete control via LQR and feedback linearization. Results provide control cost, configuration options, and capabilities as guidelines for the development of this complex mission.

Folta, David; Hartman, Kate; Howell, Kathleen; Marchand, Belinda

2004-01-01

199

Formation Control of the MAXIM L2 Libration Orbit Mission  

NASA Technical Reports Server (NTRS)

The Micro-Arcsecond X-ray Imaging Mission (MAXIM), a proposed concept for the Structure and Evolution of the Universe (SEU) Black Hole Imager mission, is designed to make a ten million-fold improvement in X-ray image clarity of celestial objects by providing better than 0.1 micro-arcsecond imaging. Currently the mission architecture comprises 25 spacecraft, 24 as optics modules and one as the detector, which will form sparse sub-apertures of a grazing incidence X-ray interferometer covering the 0.3-10 keV bandpass. This formation must allow for long duration continuous science observations and also for reconfiguration that permits re-pointing of the formation. To achieve these mission goals, the formation is required to cooperatively point at desired targets. Once pointed, the individual elements of the MAXIM formation must remain stable, maintaining their relative positions and attitudes below a critical threshold. These pointing and formation stability requirements impact the control and design of the formation. In this paper, we provide analysis of control efforts that are dependent upon the stability and the configuration and dimensions of the MAXIM formation. We emphasize the utilization of natural motions in the Lagrangian regions to minimize the control efforts and we address continuous control via input feedback linearization (IFL). Results provide control cost, configuration options, and capabilities as guidelines for the development of this complex mission.

Folta, David; Hartman, Kate; Howell, Kathleen; Marchand, Belinda

2004-01-01

200

Caffeinated alcohol use and expectancies for caffeine versus alcohol.  

PubMed

Background: Caffeinated alcoholic beverage (CAB) use is related to alcohol-related risk. Limited research has examined outcome expectancies and CAB consumption. Objectives: This study tested the predictive utility of caffeine and alcohol expectancies in CAB use outcomes (i.e. quantity, frequency, and alcohol-related harms). Methods: Participants were 419 (302 women) alcohol and caffeine users from a mid-sized urban university. Data collection occurred between August 2010 and December 2011. Participants completed measures of caffeine and alcohol expectancies, alcohol problems, alcohol use, and CAB use. Results: Caffeine and alcohol expectancies contributed uniquely to approximately 12% of the variability in quantity, 8% in frequency, and 16% in problems. When examined separately, alcohol expectancies explained approximately 10% to 11% of the variance, whereas caffeine expectancies accounted for 6% of the variance in CAB use quantity. For CAB use frequency, alcohol and caffeine expectancies accounted for about 8% and 4%, respectively. Alcohol expectancies accounted for 12% to 14% of variance, whereas caffeine expectancies accounted for 4% to 6% in alcohol-related harms. Conclusions/ Importance: The present study sought to address a gap in the literature regarding the contributions of expectancies in the prediction of CAB use. Our findings provide support for the predictive utility of both caffeine and alcohol expectancies in accounting for individual variability in CAB use but alcohol expectancies may exert greater impact on use patterns. Inclusion of both types of expectancies in larger theoretical frameworks may be beneficial in gaining a more complete and deeper conceptualization of this risky behavior. PMID:24708428

Lau-Barraco, Cathy; Linden, Ashley N

2014-08-01

201

Muscle activation level during maximal voluntary effort.  

PubMed

To assess the extent of the level of muscle activation during maximal voluntary effort, a method of superimposed trains of electrical impulses delivered at 100 Hz was employed. During a maximal voluntary contraction (MVC) in isometric knee extension, a submaximal superimposed electrical stimulation (ES) of differing train durations was induced to the quadriceps muscle, when maximal voluntary torque was achieved. For all train durations the force increased during ES. During 100 ms and longer trains, the additional torque reached a plateau. The same principle of submaximal electrical stimulation superimposed over MVC was used in explosive isometric knee extensions, comparing the rate of force growth in trials with and without ES. In all subjects ES had an augmenting effect during the increase in force and up to the maximal force. It was concluded that the subjects were not able voluntarily to activate fully their quadriceps muscle. This was true both for maximal force and for the increase in force. It seems that the existence of an activation deficit is a fact, the question is how to quantify it in a reliable and valid way. PMID:8789585

Strojnik, V

1995-01-01

202

An information maximization model of eye movements  

NASA Technical Reports Server (NTRS)

We propose a sequential information maximization model as a general strategy for programming eye movements. The model reconstructs high-resolution visual information from a sequence of fixations, taking into account the fall-off in resolution from the fovea to the periphery. From this framework we get a simple rule for predicting fixation sequences: after each fixation, fixate next at the location that minimizes uncertainty (maximizes information) about the stimulus. By comparing our model performance to human eye movement data and to predictions from a saliency and random model, we demonstrate that our model is best at predicting fixation locations. Modeling additional biological constraints will improve the prediction of fixation sequences. Our results suggest that information maximization is a useful principle for programming eye movements.

Renninger, Laura Walker; Coughlan, James; Verghese, Preeti; Malik, Jitendra

2005-01-01

203

Absence of parasympathetic reactivation after maximal exercise.  

PubMed

The ability of the human organism to recover its autonomic balance soon after physical exercise cessation has an important impact on the individual's health status. Although the dynamics of heart rate recovery after maximal exercise has been studied, little is known about heart rate variability after this type of exercise. The aim of this study is to analyse the dynamics of heart rate and heart rate variability recovery after maximal exercise in healthy young men. Fifteen healthy male subjects (21·7 ± 3·4 years; 24·0 ± 2·1 kg m(-2) ) participated in the study. The experimental protocol consisted of an incremental maximal exercise test on a cycle ergometer, until maximal voluntary exhaustion. After the test, recovery R-R intervals were recorded for 5 min. From the absolute differences between peak heart rate values and the heart rate values at 1 and 5 min of the recovery, the heart rate recovery was calculated. Postexercise heart rate variability was analysed from calculations of the SDNN and RMSSD indexes, in 30-s windows (SDNN(30s) and RMSSD(30s) ) throughout recovery. One and 5 min after maximal exercise cessation, the heart rate recovered 34·7 (±6·6) and 75·5 (±6·1) bpm, respectively. With regard to HRV recovery, while the SDNN(30s) index had a slight increase, RMSSD(30s) index remained totally suppressed throughout the recovery, suggesting an absence of vagal modulation reactivation and, possibly, a discrete sympathetic withdrawal. Therefore, it is possible that the main mechanism associated with the fall of HR after maximal exercise is sympathetic withdrawal or a vagal tone restoration without vagal modulation recovery. PMID:23383693

de Oliveira, Tiago Peçanha; de Alvarenga Mattos, Raphael; da Silva, Rhenan Bartels Ferreira; Rezende, Rafael Andrade; de Lima, Jorge Roberto Perrout

2013-03-01

204

Power-maximizing electrical energy generation system  

US Patent & Trademark Office Database

An electrical energy generation system comprising: a plurality of photovoltaic generators connected in parallel and connected to a common load via respective DC voltage converters; and a regulator configured to vary the transconductances of said respective voltage converters to maximize the power generated by said current generators; wherein: said generators are also connected to a common input of an additional voltage converter the output of which is connected to said common load; and said regulator is also configured to vary the transconductance of said additional voltage converter to maximize the power generated by said current generators.

2010-08-03

205

Neuromuscular control following maximal eccentric exercise  

Microsoft Academic Search

Kinematic and electromyographic (EMG) analysis of a target-directed, maximal velocity movement was used to investigate the\\u000a effects of high-force eccentric exercise on the neuromuscular control of elbow flexion. Ten non-weight-trained females [19.6\\u000a (1.6) years old] performed 50 maximal velocity elbow flexion movements from 0 to 1.58 rad (90°), as rapidly as possible in\\u000a response to a light stimulus, while kinematic

Mary P. Miles; Jeffrey C. Ives; Kevin R. Vincent

1997-01-01

206

Expectations in Incremental Discourse Processing  

Microsoft Academic Search

The way in which discourse features express connections back to the previous discourse has been described in the literature in terms of on a suitably defined right frontier, can be used to both process expectations and constrain discouse processing in general.

Dan Cristea; Bonnie Lynn Webber

1997-01-01

207

Web Service Hosting and Revenue Maximization  

Microsoft Academic Search

An architecture of a hosting system is presented, where a number of servers are used to provide different types of web services to paying customers. There are charges for running jobs and penalties for failing to meet agreed QualityofService requirements. The objective is to maximize the total average revenue per unit time. Dynamic policies for making server allocation and job

Michele Mazzucco; Isi Mitrani; Jennie Palmer; Mike Fisher; Paul McKee

2007-01-01

208

Web Service Hosting and Revenue Maximization  

Microsoft Academic Search

An architecture of a hosting system is presented, where a number of servers are used to provide different types of web services to paying customers. There are charges for run- ning jobs and penalties for failing to meet agreed Quality- of-Service requirements. The objective is to maximize the total average revenue per unit time. Dynamic policies for making server allocation

Michele Mazzucco; Isi Mitrani; Jennie Palmer; Mike Fisher; Paul Mckee

2007-01-01

209

Maximally Entangled Set of Multipartite Quantum States  

NASA Astrophysics Data System (ADS)

Entanglement is a resource in quantum information theory when state manipulation is restricted to local operations assisted by classical communication (LOCC). It is therefore of paramount importance to decide which LOCC transformations are possible and, particularly, which states are maximally useful under this restriction. While the bipartite maximally entangled state is well known (it is the only state that cannot be obtained from any other and, at the same time, it can be transformed to any other by LOCC), no such state exists in the multipartite case. In order to cope with this fact, we introduce here the notion of the maximally entangled set (MES) of n-partite states. This is the set of states which are maximally useful under LOCC manipulation; i.e., any state outside of this set can be obtained via LOCC from one of the states within the set and no state in the set can be obtained from any other state via LOCC. We determine the MES for states of three and four qubits and provide a simple characterization for them. In both cases, infinitely many states are required. However, while the MES is of measure zero for 3-qubit states, almost all 4-qubit states are in the MES. This is because, in contrast to the 3-qubit case, deterministic LOCC transformations are almost never possible among fully entangled four-partite states. We determine the measure-zero subset of the MES of LOCC convertible states. This is the only relevant class of states for entanglement manipulation.

de Vicente, J. I.; Spee, C.; Kraus, B.

2013-09-01

210

Maximal Indecomposable Past Sets and Event Horizons  

NASA Astrophysics Data System (ADS)

The existence of maximal indecomposable past sets MIPs is demonstrated using the Kuratowski-Zorn lemma. A criterion for the existence of an absolute event horizon in space-time is given in terms of MIPs and a relation to black hole event horizon is shown.

Królak, Andrzej

1984-02-01

211

Time machines, maximal extensions and Zorn's lemma  

NASA Astrophysics Data System (ADS)

We consider the use of Zorn's lemma in establishing the existence of maximal extensions of spacetimes, and consider Krasnikov's theorem (Krasnikov 2002 Class. Quantum Grav. 19 4109-29) on the non-existence of time machines in the light of these considerations.

Low, Robert J.

2012-05-01

212

Faculty Salaries and the Maximization of Prestige  

ERIC Educational Resources Information Center

Through the lens of the emerging economic theory of higher education, we look at the relationship between salary and prestige. Starting from the premise that academic institutions seek to maximize prestige, we hypothesize that monetary rewards are higher for faculty activities that confer prestige. We use data from the 1999 National Study of…

Melguizo, Tatiana; Strober, Myra H.

2007-01-01

213

Pattern Detection Using a Maximal Rejection Classifier  

Microsoft Academic Search

In this paper we propose a new classier - the Maximal Re- jection Classier (MRC) - for target detection. Unlike pattern recog- nition, pattern detection problems require a separation between two classes, Target and Clutter, where the probability of the former is sub- stantially smaller, compared to that of the latter. The MRC is a linear classier, based on successive

Michael Elad; Yacov Hel-or; Renato Keshet

2001-01-01

214

The maximality of the core model  

Microsoft Academic Search

If T is an iteration tree on K and F is a countably certified extender that coheres with the final model of T, then F is on the extender sequence of the final model of T. Several applications of maximality are proved, including: o K computes successors of weakly compact cardinals correctly. o K^c is an iterate of K. o

Ernest Schimmerling; John R. Steel

1997-01-01

215

Maximizing the Spectacle of Water Fountains  

ERIC Educational Resources Information Center

For a given initial speed of water from a spigot or jet, what angle of the jet will maximize the visual impact of the water spray in the fountain? This paper focuses on fountains whose spigots are arranged in circular fashion, and couches the measurement of the visual impact in terms of the surface area and the volume under the fountain's natural…

Simoson, Andrew J.

2009-01-01

216

The Winning Edge: Maximizing Success in College.  

ERIC Educational Resources Information Center

This book offers college students ideas on how to maximize their success in college by examining the personal management techniques a student needs to succeed. Chapters are as follows: "Getting and Staying Motivated"; "Setting Goals and Tapping Your Resources"; "Conquering Time"; "Think Yourself to College Success"; "Understanding and Remembering…

Schmitt, David E.

217

Formation Control for the Maxim Mission.  

NASA Technical Reports Server (NTRS)

Over the next twenty years, a wave of change is occurring in the spacebased scientific remote sensing community. While the fundamental limits in the spatial and angular resolution achievable in spacecraft have been reached, based on today's technology, an expansive new technology base has appeared over the past decade in the area of Distributed Space Systems (DSS). A key subset of the DSS technology area is that which covers precision formation flying of space vehicles. Through precision formation flying, the baselines, previously defined by the largest monolithic structure which could fit in the largest launch vehicle fairing, are now virtually unlimited. Several missions including the Micro-Arcsecond X-ray Imaging Mission (MAXIM), and the Stellar Imager will drive the formation flying challenges to achieve unprecedented baselines for high resolution, extended-scene, interferometry in the ultraviolet and X-ray regimes. This paper focuses on establishing the feasibility for the formation control of the MAXIM mission. The Stellar Imager mission requirements are on the same order of those for MAXIM. This paper specifically addresses: (1) high-level science requirements for these missions and how they evolve into engineering requirements; (2) the formation control architecture devised for such missions; (3) the design of the formation control laws to maintain very high precision relative positions; and (4) the levels of fuel usage required in the duration of these missions. Specific preliminary results are presented for two spacecraft within the MAXIM mission.

Luquette, Richard J.; Leitner, Jesse; Gendreau, Keith; Sanner, Robert M.

2004-01-01

218

Maximizing system lifetime in wireless sensor networks  

Microsoft Academic Search

Maximizing system lifetime in battery-powered wire- less sensor networks with power aware topology control protocols and routing protocols has received intensive research. In the past, this problem has been mostly studied from the indirect perspective of energy conser- vation. Although this leads to solutions that help ex- tend network lifetime, energy conservation is not the same problem as network lifetime

Qunfeng Dong

2005-01-01

219

Maximal Inequalities for Multidimensionally Indexed Submartingale Arrays  

Microsoft Academic Search

Some new maximal-type probability inequalities are developed for discrete-time multidimensionally indexed submartingales. In particular, the basic idea of Chow is abstracted and extended. This leads to a result which yields extended Kolmogorov inequalities and strong laws, extended Hajek-Renyi type inequalities competitive with Smythe and an extended Doob inequality which is counter-intuitive to a counterexample of Cairoli.

Tasos C. Christofides; Robert J. Serfling

1990-01-01

220

Maximizing the Motivated Mind for Emergent Giftedness.  

ERIC Educational Resources Information Center

This article explains how the theory of the motivated mind conceptualizes the productive interaction of intelligence, creativity, and achievement motivation and how this theory can help educators to maximize students' emergent potential for giftedness. It discusses the integration of cold-order thinking and hot-chaotic thinking into fluid-adaptive…

Rea, Dan

2001-01-01

221

MAXIMAL FUNCTION ON GENERALIZED LEBESGUE SPACES Lp(·)  

Microsoft Academic Search

We prove the boundedness of the Hardy-Littlewood maximal function on the general- ized Lebesgue space Lp(·)(Rd) under a continuity assumption on p that is weaker than uniform H¨ older continuity. We deduce continuity of mollifying sequences and density of C?(?) in W1,p(·)(?).

L. DIENING

222

Ehrenfest's Lottery--Time and Entropy Maximization  

ERIC Educational Resources Information Center

Successful teaching of the Second Law of Thermodynamics suffers from limited simple examples linking equilibrium to entropy maximization. I describe a thought experiment connecting entropy to a lottery that mixes marbles amongst a collection of urns. This mixing obeys diffusion-like dynamics. Equilibrium is achieved when the marble distribution is…

Ashbaugh, Henry S.

2010-01-01

223

Finding All Maximal Cliques in Dynamic Graphs  

Microsoft Academic Search

Clustering applications dealing with perception based or biased data lead to models with non-disjunct clusters. There, objects to be clustered are allowed to belong to several clusters at the same time which results in a fuzzy clustering. It can be shown that this is equivalent to searching all maximal cliques in dynamic graphs like Gt = (V,Et), where Et -

Volker Stix

2004-01-01

224

More Is Better: Maximizing Natural Learning Opportunities.  

ERIC Educational Resources Information Center

This article discusses the increased emphasis on providing early intervention services within natural environments and how to maximize natural learning opportunities by using everyday activities that children experience and embedding intervention in daily routines. Guidelines for deciding the frequency of services, changing services, and the level…

Jung, Lee Ann

2003-01-01

225

Linkages between cigarette smoking outcome expectancies and negative emotional vulnerability  

Microsoft Academic Search

The present investigation examined whether smoking outcome expectancies, as measured by the Smoking Consequences Questionnaire (SCQ; [Brandon, T.H., & Baker, T.B., (1991). The Smoking Consequences Questionnaire: The subjective expected utility of smoking in college students. Psychological Assessment, 3, 484–491.]), were incrementally related to emotional vulnerability factors among an adult sample of 202 daily cigarette smokers (44.6% women; Mage=23.78 years, SD=9.69 years). After

Kirsten A. Johnson; Michael J. Zvolensky; Erin C. Marshall; Adam Gonzalez; Kenneth Abrams; Anka A. Vujanovic

2008-01-01

226

Support expectations of cancer patients.  

PubMed

Patients' satisfaction is a paramount in the delivery of health care provisions, particularly in patients with poor prognosis. Effective communication with such patients helps in achieving a better satisfaction score. A survey was conducted on upper gastrointestinal cancer patients to assess their perceived satisfaction regarding the healthcare received. A frank but supportive communication helps in meeting the expectations of these patients in their cancer journey. PMID:23374529

Jafferbhoy, Sadaf; Tappenden, Janine; Allen, Tracey; Shiwani, Muhammad Hanif

2013-02-01

227

Televisions, Physicians, and Life Expectancy  

NSDL National Science Digital Library

This article, created by Allan Rossman of Dickinson College, describes a dataset on life expectancies, densities of people per television set, and densities of people per physician in various countries of the world. The example addresses correlation versus causation and data transformations. The author states that "the example has proven very useful for helping students to discover the fundamental principle that correlation does not imply causation."

Rossman, Allan

2009-06-22

228

[Initial masseter muscle fatigue in maximal voluntary teeth clenching].  

PubMed

Fatigue of striated muscles is defined as the impossibility to generate the expected or required force during the repeated contraction. During the maximal voluntary teeth contraction in the position of central occlusion the initial fatigue in masticatory muscles during the isometric contraction occurs. If a person can clench its teeth continuously and voluntarily it has a diagnostic significance since the peripheral fatigue is that important factor in the masticatory muscles activity, which is in direct correlation with the function of the masticatory system. The aim was to compare the obtained results of the initial fatigue of masseter muscles during the maximal voluntary teeth contraction in subjects with naturally healthy intact dentition and subjects with a pair of new full dentures. The investigation comprised 20 subjects with healthy stomatognathic system of the skeletal class I by Angle. Comparison of the values of the obtained results was performed electromyographically by synchronous registration of action potentials of masseter muscles. Results of the investigation of the onset of initial fatigue of masseter muscles in the subjects with natural healthy intact dentions showed lower values, i.e., faster development of the muscular fatigue (31.5 s) compared to the subjects with a pair of new full dentures (44.5 s). PMID:11928190

Miljkovi?, Hivorad; Zeljkovi?, Milan; Anojci?, Milos

2002-01-01

229

Loops and multiple edges in modularity maximization of networks  

NASA Astrophysics Data System (ADS)

The modularity maximization model proposed by Newman and Girvan for the identification of communities in networks works for general graphs possibly with loops and multiple edges. However, the applications usually correspond to simple graphs. These graphs are compared to a null model where the degree distribution is maintained but edges are placed at random. Therefore, in this null model there will be loops and possibly multiple edges. Sharp bounds on the expected number of loops, and their impact on the modularity, are derived. Then, building upon the work of Massen and Doye, but using algebra rather than simulation, we propose modified null models associated with graphs without loops but with multiple edges, graphs with loops but without multiple edges and graphs without loops nor multiple edges. We validate our models by using the exact algorithm for clique partitioning of Grötschel and Wakabayashi.

Cafieri, Sonia; Hansen, Pierre; Liberti, Leo

2010-04-01

230

Optimal design of structural support positions for minimizing maximal bending moment  

Microsoft Academic Search

The design of the structural supports has always been practically important in engineering applications. In addition to holding a structure properly, supports can also be utilized to improve the structural performances. For this purpose, this paper presents an appropriate optimization scheme of minimization of the maximal absolute bending moment in a planar frame by means of the optimal design of

D. Wang

2006-01-01

231

Maximal Strength Training Improves Running Economy in Distance Runners  

Microsoft Academic Search

STKREN, K., J. HELGERUD, E. M. STKA, and J. HOFF. Maximal Strength Training Improves Running Economy in Distance Runners. Med. Sci. Sports Exerc., Vol. 40, No. 6, pp. 1089-1094, 2008. Purpose: The present study investigated the effect of maximal strength training on running economy (RE) at 70% of maximal oxygen consumption (VO2max) and time to exhaustion at maximal aerobic speed

KYVIND STKREN; JAN HELGERUD; EVA MARIA STKA; JAN HOFF

2008-01-01

232

Using return on investment to maximize conservation effectiveness in Argentine grasslands  

PubMed Central

The rapid global loss of natural habitats and biodiversity, and limited resources, place a premium on maximizing the expected benefits of conservation actions. The scarcity of information on the fine-grained distribution of species of conservation concern, on risks of loss, and on costs of conservation actions, especially in developing countries, makes efficient conservation difficult. The distribution of ecosystem types (unique ecological communities) is typically better known than species and arguably better represents the entirety of biodiversity than do well-known taxa, so we use conserving the diversity of ecosystem types as our conservation goal. We define conservation benefit to include risk of conversion, spatial effects that reward clumping of habitat, and diminishing returns to investment in any one ecosystem type. Using Argentine grasslands as an example, we compare three strategies: protecting the cheapest land (“minimize cost”), maximizing conservation benefit regardless of cost (“maximize benefit”), and maximizing conservation benefit per dollar (“return on investment”). We first show that the widely endorsed goal of saving some percentage (typically 10%) of a country or habitat type, although it may inspire conservation, is a poor operational goal. It either leads to the accumulation of areas with low conservation benefit or requires infeasibly large sums of money, and it distracts from the real problem: maximizing conservation benefit given limited resources. Second, given realistic budgets, return on investment is superior to the other conservation strategies. Surprisingly, however, over a wide range of budgets, minimizing cost provides more conservation benefit than does the maximize-benefit strategy.

Murdoch, William; Ranganathan, Jai; Polasky, Stephen; Regetz, James

2010-01-01

233

Semi-supervised information-maximization clustering.  

PubMed

Semi-supervised clustering aims to introduce prior knowledge in the decision process of a clustering algorithm. In this paper, we propose a novel semi-supervised clustering algorithm based on the information-maximization principle. The proposed method is an extension of a previous unsupervised information-maximization clustering algorithm based on squared-loss mutual information to effectively incorporate must-links and cannot-links. The proposed method is computationally efficient because the clustering solution can be obtained analytically via eigendecomposition. Furthermore, the proposed method allows systematic optimization of tuning parameters such as the kernel width, given the degree of belief in the must-links and cannot-links. The usefulness of the proposed method is demonstrated through experiments. PMID:24975502

Calandriello, Daniele; Niu, Gang; Sugiyama, Masashi

2014-09-01

234

Nondecoupling of maximal supergravity from the superstring.  

PubMed

We consider the conditions necessary for obtaining perturbative maximal supergravity in d dimensions as a decoupling limit of type II superstring theory compactified on a (10-d) torus. For dimensions d=2 and d=3, it is possible to define a limit in which the only finite-mass states are the 256 massless states of maximal supergravity. However, in dimensions d>or=4, there are infinite towers of additional massless and finite-mass states. These correspond to Kaluza-Klein charges, wound strings, Kaluza-Klein monopoles, or branes wrapping around cycles of the toroidal extra dimensions. We conclude that perturbative supergravity cannot be decoupled from string theory in dimensions>or=4. In particular, we conjecture that pure N=8 supergravity in four dimensions is in the Swampland. PMID:17678349

Green, Michael B; Ooguri, Hirosi; Schwarz, John H

2007-07-27

235

Maximally discordant mixed states of two qubits  

SciTech Connect

We study the relative strength of classical and quantum correlations, as measured by discord, for two-qubit states. Quantum correlations appear only in the presence of classical correlations, while the reverse is not always true. We identify the family of states that maximize the discord for a given value of the classical correlations and show that the largest attainable discord for mixed states is greater than for pure states. The difference between discord and entanglement is emphasized by the remarkable fact that these states do not maximize entanglement and are, in some cases, even separable. Finally, by random generation of density matrices uniformly distributed over the whole Hilbert space, we quantify the frequency of the appearance of quantum and classical correlations for different ranks.

Galve, Fernando; Giorgi, Gian Luca; Zambrini, Roberta [IFISC (UIB-CSIC), Instituto de Fisica Interdisciplinar y Sistemas Complejos, UIB Campus, E-07122 Palma de Mallorca (Spain)

2011-01-15

236

Time flies when you maximize - maximizers and satisficers perceive time differently when making decisions.  

PubMed

Three experiments assessed whether maximizing and satisficing decision-making types were associated with differences in perception of time, as a consequence of their different cognitive workloads. Findings showed that maximizers and satisficers perceived time differently during decision-making, but not during other tasks. In particular, compared to satisficers, maximizers tended to underestimate time while choosing, independently of the number of options and the specific task requirements. Satisficers instead tended to underestimate time only when the number of options or the task requirements were more challenging. Our findings suggest that the perception of time may serve as a measure of the cognitive workload associated with decision-making types. The findings furthermore suggest that satisficers adopt a more malleable decision-making process than maximizers. PMID:23584103

Misuraca, Raffaella; Teuscher, Ursina

2013-06-01

237

Subset Weight Maximization with Two Competing Agents  

Microsoft Academic Search

We consider a game of two agents competing to add items into a solution set. Each agent owns a set of weighted items and seeks\\u000a to maximize the sum of their weights in the solution set. In each round each agent submits one item for inclusion in the solution.\\u000a We study two natural rules to decide the winner of each

Gaia Nicosia; Andrea Pacifici; Ulrich Pferschy

2009-01-01

238

Maximizing the motivated mind for emergent giftedness  

Microsoft Academic Search

The main goals of this article are to explain how the theory of the motivated mind conceptualizes the productive interaction of intelligence, creativity, and achievement motivation and to show how this theory can help educators to maximize students' emergent potential for giftedness. According to this theory, students' motivated minds are complex?adaptive systems comprised of two co?evolving psychological subsystems: cold?order thinking

Dan Rea

2001-01-01

239

Maximal acceleration is non-rotating  

NASA Astrophysics Data System (ADS)

In a stationary axisymmetric spacetime, the angular velocity of a stationary observer whose acceleration vector is Fermi-Walker transported is also the angular velocity that locally extremizes the magnitude of the acceleration of such an observer. The converse is also true if the spacetime is symmetric under reversing both t and 0264-9381/15/6/020/img1 together. Thus a congruence of non-rotating acceleration worldlines (NAW) is equivalent to a stationary congruence accelerating locally extremely (SCALE). These congruences are defined completely locally, unlike the case of zero angular momentum observers (ZAMOs), which requires knowledge around a symmetry axis. The SCALE subcase of a stationary congruence accelerating maximally (SCAM) is made up of stationary worldlines that may be considered to be locally most nearly at rest in a stationary axisymmetric gravitational field. Formulae for the angular velocity and other properties of the SCALEs are given explicitly on a generalization of an equatorial plane, infinitesimally near a symmetry axis, and in a slowly rotating gravitational field, including the far-field limit, where the SCAM is shown to be counter-rotating relative to infinity. These formulae are evaluated in particular detail for the Kerr-Newman metric. Various other congruences are also defined, such as a stationary congruence rotating at minimum (SCRAM), and stationary worldlines accelerating radially maximally (SWARM), both of which coincide with a SCAM on an equatorial plane of reflection symmetry. Applications are also made to the gravitational fields of maximally rotating stars, the Sun and the Solar System.

Page, Don N.

1998-06-01

240

Uplink Array Calibration via Far-Field Power Maximization  

NASA Technical Reports Server (NTRS)

Uplink antenna arrays have the potential to greatly increase the Deep Space Network s high-data-rate uplink capabilities as well as useful range, and to provide additional uplink signal power during critical spacecraft emergencies. While techniques for calibrating an array of receive antennas have been addressed previously, proven concepts for uplink array calibration have yet to be demonstrated. This article describes a method of utilizing the Moon as a natural far-field reflector for calibrating a phased array of uplink antennas. Using this calibration technique, the radio frequency carriers transmitted by each antenna of the array are optimally phased to ensure that the uplink power received by the spacecraft is maximized.

Vilnrotter, V.; Mukai, R.; Lee, D.

2006-01-01

241

Primary Care Clinician Expectations Regarding Aging  

ERIC Educational Resources Information Center

Purpose: Expectations regarding aging (ERA) in community-dwelling older adults are associated with personal health behaviors and health resource usage. Clinicians' age expectations likely influence patients' expectations and care delivery patterns; yet, limited research has explored clinicians' age expectations. The Expectations Regarding Aging…

Davis, Melinda M.; Bond, Lynne A.; Howard, Alan; Sarkisian, Catherine A.

2011-01-01

242

Normative Expectations and Individual Decisions concerning Media Gratification Choices.  

ERIC Educational Resources Information Center

Results indicate that each of the nine media studied (newspapers, magazines, commercial and public television, books, radio, friends, recorded music, film) has a clear, socially defined image, suggesting a two-stage model of media channel utilization--normative expectations followed by individual decisions. (PD)

Lichtenstein, Allen; Rosenfeld, Lawrence

1984-01-01

243

Visual Search Performance and Observer Expectations.  

National Technical Information Service (NTIS)

A field experiment is reported in which subject's expectations regarding cues to detection of selected target types, and the effect such expectations might have on time to detection, were investigated. A scenario procedure for measurement of expectations ...

C. J. Woodruff

1986-01-01

244

Insufficient ct data reconstruction based on directional total variation (dtv) regularized maximum likelihood expectation maximization (mlem) method  

NASA Astrophysics Data System (ADS)

Sparse tomography is an efficient technique which saves time as well as minimizes cost. However, due to few angular data it implies the image reconstruction problem as ill-posed. In the ill posed problem, even with exact data constraints, the inversion cannot be uniquely performed. Therefore, selection of suitable method to optimize the reconstruction problems plays an important role in sparse data CT. Use of regularization function is a well-known method to control the artifacts in limited angle data acquisition. In this work, we propose directional total variation regularized ordered subset (OS) type image reconstruction method for neutron limited data CT. Total variation (TV) regularization works as edge preserving regularization which not only preserves the sharp edge but also reduces many of the artifacts that are very common in limited data CT. However TV itself is not direction dependent. Therefore, TV is not very suitable for images with a dominant direction. The images with dominant direction it is important to know the total variation at certain direction. Hence, here a directional TV is used as prior term. TV regularization assumes the constraint of piecewise smoothness. As the original image is not piece wise constant image, sparsifying transform is used to convert the image in to sparse image or piecewise constant image. Along with this regularized function (D TV) the likelihood function which is adapted as objective function. To optimize this objective function a OS type algorithm is used. Generally there are two methods available to make OS method convergent. This work proposes OS type directional TV regularized likelihood reconstruction method which yields fast convergence as well as good quality image. Initial iteration starts with the filtered back projection (FBP) reconstructed image. The indication of convergence is determined by the convergence index between two successive reconstructed images. The quality of the image is assessed by showing the line profile of the reconstructed image. The proposed method is compared with the commonly used FBP, MLEM, and MLEM-TV algorithm. In order to verify the performance of the proposed algorithm a Shep-Logan head phantom is simulated as well as a real neutron CT image is tested to demonstrate the feasibility of the algorithm for the practical sparse CT reconstruction applications.

Islam, Fahima Fahmida

245

Human Tracking System Integrating Sound and Face Localization Using an Expectation-Maximization Algorithm in Real Environments  

Microsoft Academic Search

We have developed a human tracking system for use by robots that integrate sound and face localization. Conventional systems usually require many microphones and\\/or prior information to localize several sound sources. Moreover, they are incapable of coping with various types of background noise. Our system, the cross-power spectrum phase analysis of sound signals obtained with only two microphones, is used

Hyun-Don Kim; Kazunori Komatani; Tetsuya Ogata; Hiroshi G. Okuno

2009-01-01

246

Robust Expectation-Maximization Algorithm for Multiple Wideband Acoustic Source Localization in the Presence of Nonuniform Noise Variances  

Microsoft Academic Search

Wideband source localization using acoustic sensor networks has been drawing a lot of research interest recently. The maximum-likelihood is the predominant objective which leads to a variety of source localization approaches. However, the robust and efficient optimization algorithms are still being pursuit by researchers since different aspects about the effectiveness of such algorithms have to be addressed on different circumstances.

Lu Lu; Hsiao-Chun Wu; Kun Yan; S. S. Iyengar

2011-01-01

247

Simultaneous analysis and design for eigenvalue maximization  

NASA Technical Reports Server (NTRS)

A simultaneous analysis and design approach to the maximization of buckling or vibration eigenvalues is presented. Both unimodal and bimodal optimum solutions are considered. A discretization of the structure and response is used to obtain sets of nonlinear algebraic equations which are solved numerically. The formulation is applied to the solution of the optimum design of a beam-column supported by an elastic foundation for maximum buckling load. Two cases are considered: the optimum design of the column for a given foundation and the optimum design of the foundation for a given column. Results are compared to published solutions when possible.

Plaut, Raymond H.; Haftka, Raphael T.; Shin, Yung S.

1987-01-01

248

Electromagnetically induced grating with maximal atomic coherence  

SciTech Connect

We describe theoretically an atomic diffraction grating that combines an electromagnetically induced grating with a coherence grating in a double-{Lambda} atomic system. With the atom in a condition of maximal coherence between its lower levels, the combined gratings simultaneously diffract both the incident probe beam as well as the signal beam generated through four-wave mixing. A special feature of the atomic grating is that it will diffract any beam resonantly tuned to any excited state of the atom accessible by a dipole transition from its ground state.

Carvalho, Silvania A.; Araujo, Luis E. E. de [Instituto de Fisica ''Gleb Wataghin'', Universidade Estadual de Campinas, Campinas-SP, 13083-859 Sao Paulo (Brazil)

2011-10-15

249

Maximally entangled mixed states and conditional entropies  

SciTech Connect

The maximally entangled mixed states of Munro et al. [Phys. Rev. A 64, 030302 (2001)] are shown to exhibit interesting features vis a vis conditional entropic measures. The same happens with the Ishizaka and Hiroshima states [Phys. Rev. A 62, 022310 (2000)], whose entanglement degree cannot be increased by acting on them with logic gates. Special types of entangled states that do not violate classical entropic inequalities are seen to exist in the space of two qubits. Special meaning can be assigned to the Munro et al. special participation ratio of 1.8.

Batle, J.; Casas, M. [Departament de Fisica, Universitat de les Illes Balears and IMEDEA-CSIC, 07122 Palma de Mallorca (Spain); Plastino, A. [Argentina's National Research Council (CONICET), Casilla de Correo 727, 1900 La Plata (Argentina); Department of Physics, National University La Plata, Casilla de Correo 727, 1900 La Plata (Argentina); Plastino, A.R. [Department of Physics, National University La Plata, Casilla de Correo 727, 1900 La Plata (Argentina); Faculty of Astronomy and Geophysics, National University La Plata, Casilla de Correo 727, 1900 La Plata (Argentina); Department of Physics, University of Pretoria, 0002 Pretoria (South Africa)

2005-02-01

250

Detection of the maximally connected state  

SciTech Connect

The maximally connected state (MCS) which was first introduced by Briegel and Raussendorf [Phys. Rev. Lett. 86, 910 (2001)] has many interesting properties in quantum information theory. Many important states that we are focusing on currently are included in this special set of states. To decide whether a state is a MCS or not is the main problem concerned in this paper. In this paper (1) we give a general criterion for MCS; (2) when the ranks of all of the two-qubit reduced density matrices are two, we give a convenient criterion.

Han, Y.-J.; Hu, Y.; Zhang, Y.-S.; Guo, G.-C. [Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026 (China)

2005-12-15

251

FACTORS WHICH CONTROL MAXIMAL GROWTH OF BACTERIA  

PubMed Central

Sinclair, N. A. (Washington State University, Pullman) and J. L. Stokes. Factors which control maximal growth of bacteria. J. Bacteriol. 83:1147–1154. 1962.—In a chemically defined medium containing 1% glucose and 0.1% (NH4)2SO4, both of these compounds are virtually exhausted by the growth of Pseudomonas fluorescens. If these carbon, energy, and nitrogen sources are added back to the culture filtrate, maximal growth to the level of the original culture is obtained. This process can be repeated several times with the same results. Eventually, however, the supply of minerals in the culture limits growth. When the nutrient levels are raised to 3% glucose and 0.3% (NH4)2SO4, lack of oxygen and low pH limit growth before the supply of nutrients is exhausted. There is no evidence that specific autoinhibitory substances are produced either in chemically defined or complex nitrogenous media or that physical crowding of the cells limits growth. The results with Escherichia coli are similar to those with P. fluorescens. However, after a few growth cycles aerobically and after only one growth cycle anaerobically, inhibitory substances, probably organic acids, accumulate and limit growth.

Sinclair, N. A.; Stokes, J. L.

1962-01-01

252

THE EMPIRICAL VALUE-AT-RISK\\/EXPECTED RETURN FRONTIER: A USEFUL TOOL OF MARKET RISK MANAGING  

Microsoft Academic Search

In addition to measuring and monitoring financial risk, it is important for risk managers to understand how financial risky portfolios can be restructured effectively to reduce risk and maximize expected returns. Risk management tools for market risk are largely based on Modern Portfolio Theory and assume that the profit and loss (or the return) distributions are normal. In a normal

Annalisa Di Clemente

253

Nonverbal Expectancy Effects in the Political Media.  

ERIC Educational Resources Information Center

Expectancy effects--the unconscious shaping of receiver behavior by signalling sender expectations--while recognized in science, have not been documented extensively from a communication perspective, nor are nonverbal aspects of expectancy effects fully known. Expectancy is a function of three elements, the sender's predisposition (including…

Corder, Lloyd E.

254

Changing Role Expectations of Psychiatric Occupational Therapists  

Microsoft Academic Search

Psychiatric occupational therapists have experienced multiple changes in role expectations with the move from long term care to short term care. These expectations have caused frustration, low self-esteem, and job dissatisfaction. These feelings may be better understood in terms of expectation generated stressors as identified by organization theorists. Having reviewed these stressors, this article will review role expectation changes of

Janet E. Short

1984-01-01

255

Effects of Psychophysical Lifting Training on Maximal Repetitive Lifting Capacity.  

National Technical Information Service (NTIS)

The purpose of this investigation was to determine the effectiveness of psychophysical lifting training on maximal repetitive lifting capacity. Maximal repetitive lifting capacity was defined as the maximum box mass that could be lifted for a full hour to...

M. A. Sharp S. J. Legg

1987-01-01

256

A Comparison of Three Maximal Treadmill Exercise Protocols.  

National Technical Information Service (NTIS)

Fifteen volunteers performed the Bruce, Balke, and Taylor maximal treadmill exercise protocols. Each protocol was performed by each individual three times, one test a week for nine weeks, in randomized order. Maximal and submaximal oxygen consumption and ...

V. F. Froelicher H. Brammell M. Lancaster

1973-01-01

257

Racial differences in patient expectations prior to resective epilepsy surgery  

PubMed Central

We assessed the nature and frequency of preoperative expectations among patients with refractory epilepsy who were enrolled in a seven-center observational study of epilepsy surgery outcomes. At enrollment, patients responded to open-ended questions about expectations for surgical outcome. Using an iterative cutting and sorting technique, expectation themes were identified and rank-ordered. Associations of expectations with race/ethnicity were evaluated. Among 391 respondents, the two most frequently endorsed expectations (any rank order) were driving (62%) and job/school (43%). When only the most important (first-ranked order) expectation was analyzed, driving (53%) and cognition (17%) were most frequently offered. Non-whites endorsed job/school and cognition more frequently and driving less frequently than whites (all p?0.05), whether we included expectations of any order or only the first ranked ones. Elucidating the reason for these differences can aid in the clinical decision-making process for resective surgery and potentially address disparities in its utilization.

Baca, Christine Bower; Cheng, Eric M.; Spencer, Susan S.; Vassar, Stefanie; Vickrey, Barbara G.

2009-01-01

258

Biomass utilization  

Microsoft Academic Search

Forty papers are presented in 6 sections: Biomass utilization - the concept; The raw material and its preparation; The structure and chemical composition of biomass; Conversion methods - biological; Conversion methods - thermochemical; and Engineering and economics in biomass utilization. Ten papers are of particular forestry interest: Forest inventories as the basis for a continuous monitoring of forest biomass resources

Coute

1983-01-01

259

Utility diversification  

SciTech Connect

After reviewing the pros and cons of public utility diversification, the author concludes that the balance of public interest is on the side of permitting public utility companies greater freedom to diversify than they now enjoy. He would eliminate the review of individual proposed investments outside of the public utility area on the grounds that regulators have no particular competence in this area. He would also eliminate the regulation of security issuances and dividend payments by the nonpublic utility entities. Regulation should see that the diversifying enterprise is structured and regulation of the utility entity so conducted as to insulate monoply ratepayers from risks as much as possible. This would limit regulation of the nonutility entity to seeing that the total size of the company's commitment to new diversification ventures does not threaten deterioration of the credit of the entire enterprise. 3 references.

Kahn, A.E.

1983-01-01

260

Maximal diagnosis of interconnects of random access memories  

Microsoft Academic Search

This paper presents an approach for the maximal diagnosis of all faults (stuck-at, open and short) in the interconnect of a random access memory (RAM); and the interconnect includes data and address lines. This approach accomplishes maximal diagnosis under a complex model in which the lines in the interconnect of the RAM can be affected by multiple faults. Maximal diagnosis

Jun Zhao; Fred J. Meyer; Fabrizio Lombardi

2003-01-01

261

Maximal inspiratory pressure: does reproducibility indicate full effort?  

Microsoft Academic Search

BACKGROUND--Maximal inspiratory pressure (MIP) is often relied upon as an index of inspiratory muscle strength, and reproducibility of MIP taken to indicate maximal effort. This study was designed to determine whether reproducibility is a valid indicator of maximal effort. METHODS--Ten normal subjects were studied, all of whom were familiar with the MIP test but none was an experienced subject. They

T K Aldrich; P Spiro

1995-01-01

262

Multiparameter Maximal Functions Along Dilation-Invariant Hypersurfaces.  

National Technical Information Service (NTIS)

The maximal function operator associated to the equation of a hypersurface is defined. That this operator is bounded on L sup p spaces is proved. This boundedness is established by one-dimensional maximal functions. Methods for maximal function along curv...

H. Carlsson P. Sjoegren J. O. Stroemberg

1984-01-01

263

Anaerobic contribution during maximal anaerobic running test: correlation with maximal accumulated oxygen deficit.  

PubMed

The aims of this study were: (i) to measure energy system contributions in maximal anaerobic running test (MART); and (ii) to verify any correlation between MART and maximal accumulated oxygen deficit (MAOD). Eleven members of the armed forces were recruited for this study. Participants performed MART and MAOD, both accomplished on a treadmill. MART consisted of intermittent exercise, 20 s effort with 100 s recovery, after each spell of effort exercise. Energy system contributions by MART were also determined by excess post-exercise oxygen consumption, lactate response, and oxygen uptake measurements. MAOD was determined by five submaximal intensities and one supramaximal intensity exercises corresponding to 120% at maximal oxygen uptake intensity. Energy system contributions were 65.4±1.1% to aerobic; 29.5±1.1% to anaerobic a-lactic; and 5.1±0.5% to anaerobic lactic system throughout the whole test, while only during effort periods the anaerobic contribution corresponded to 73.5±1.0%. Maximal power found in MART corresponded to 111.25±1.33 mL/kg/min but did not significantly correlate with MAOD (4.69±0.30 L and 70.85±4.73 mL/kg). We concluded that the anaerobic a-lactic system is the main energy system in MART efforts and this test did not significantly correlate to MAOD. PMID:21210856

Zagatto, A; Redkva, P; Loures, J; Kalva Filho, C; Franco, V; Kaminagakura, E; Papoti, M

2011-12-01

264

Maximal deformation of an impacting drop  

NASA Astrophysics Data System (ADS)

We first study the impact of a liquid drop of low viscosity on a super-hydrophobic surface. Denoting the drop size and speed as D_{0} and U_{0}, we find that the maximal spreading D_{scriptsizemax} scales as D_{0}We(1/4) where We is the Weber number associated with the shock (We {equiv} rho U_{0}(2) D_{0}/sigma, where rho and sigma are the liquid density and surface tension). This law is also observed to hold on partially wettable surfaces, provided that liquids of low viscosity (such as water) are used. The law is interpreted as resulting from the effective acceleration experienced by the drop during its impact. Viscous drops are also analysed, allowing us to propose a criterion for predicting if the spreading is limited by capillarity, or by viscosity.

Clanet, Christophe; Béguin, Cédric; Richard, Denis; Quéré, David

2004-10-01

265

Maximally polarized states for quantum light fields  

SciTech Connect

The degree of polarization of a quantum field can be defined as its distance to an appropriate set of states. When we take unpolarized states as this reference set, the states optimizing this degree for a fixed average number of photons N present a fairly symmetric, parabolic photon statistic, with a variance scaling as N{sup 2}. Although no standard optical process yields such a statistic, we show that, to an excellent approximation, a highly squeezed vacuum can be taken as maximally polarized. We also consider the distance of a field to the set of its SU(2) transformed, finding that certain linear superpositions of SU(2) coherent states make this degree to be unity.

Sanchez-Soto, Luis L.; Yustas, Eulogio C. [Departamento de Optica, Facultad de Fisica, Universidad Complutense, 28040 Madrid (Spain); Bjoerk, Gunnar [School of Information and Communication Technology, Royal Institute of Technology (KTH), Electrum 229, SE-164 40 Kista (Sweden); Klimov, Andrei B. [Departamento de Fisica, Universidad de Guadalajara, 44420 Guadalajara, Jalisco (Mexico)

2007-10-15

266

Utility diversification  

SciTech Connect

A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect recipients of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

Kahn, A.E.

1983-01-01

267

Utility diversification  

SciTech Connect

A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect consumers of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

Kahn, A.E.

1982-01-01

268

Chemical structure elucidation from (13)c NMR chemical shifts: efficient data processing using bipartite matching and maximal clique algorithms.  

PubMed

Computer-assisted chemical structure elucidation has been intensively studied since the first use of computers in chemistry in the 1960s. Most of the existing elucidators use a structure-spectrum database to obtain clues about the correct structure. Such a structure-spectrum database is expected to grow on a daily basis. Hence, the necessity to develop an efficient structure elucidation system that can adapt to the growth of a database has been also growing. Therefore, we have developed a new elucidator using practically efficient graph algorithms, including the convex bipartite matching, weighted bipartite matching, and Bron-Kerbosch maximal clique algorithms. The utilization of the two matching algorithms especially is a novel point of our elucidator. Because of these sophisticated algorithms, the elucidator exactly produces a correct structure if all of the fragments are included in the database. Even if not all of the fragments are in the database, the elucidator proposes relevant substructures that can help chemists to identify the actual chemical structures. The elucidator, called the CAST/CNMR Structure Elucidator, plays a complementary role to the CAST/CNMR Chemical Shift Predictor, and together these two functions can be used to analyze the structures of organic compounds. PMID:24655374

Koichi, Shungo; Arisaka, Masaki; Koshino, Hiroyuki; Aoki, Atsushi; Iwata, Satoru; Uno, Takeaki; Satoh, Hiroko

2014-04-28

269

Leader Behavior: An Expectancy Theory Approach.  

National Technical Information Service (NTIS)

Expectancy theory has found increasing use in the study of such variables as worker efforts, performance and satisfaction. The paper suggests some mathematical modifications of expectancy theory which extend its use to the prediction of leader behavior. D...

D. M. Nebeker T. R. Mitchell

1973-01-01

270

Nursing students' expectations of the college experience.  

PubMed

Nursing students' expectations of college have not received much attention in the empirical literature. These expectations may be important in better understanding nurses' motivations, role acquisition, and academic and professional success. The first study discussed in this article examined the reliability and construct validity of an instrument designed to assess students' (N = 95) expectations of their college experience. The results indicate good reliability and validity. The second study discussed in this article examined differences in expectations, comparing nursing and non-nursing students (N = 160) in an urban college setting. The results suggest expectations emphasizing practical and professional aspects (i.e., acquiring a profession, earning more money), followed by self-betterment and social life expectations. Nursing students differed from non-nursing students by reporting higher self-betterment and professional expectations but lower academic expectations. Implications for application and further research are discussed. PMID:18792705

Zysberg, Leehu; Zisberg, Anna

2008-09-01

271

Higher Order Expectations in Asset Pricing  

Microsoft Academic Search

We examine formally Keynes' idea that higher order beliefs can drive a wedge between an asset price and its fundamental value based on expected future payoffs. Higher order expectations add an additional term to a standard asset pricing equation. We call this the higher order wedge, which depends on the difference between higher and first order expectations of future payoffs.

Philippe Bacchetta; Eric van Wincoop

2008-01-01

272

Explanatory style, expectations, and depressive symptoms  

Microsoft Academic Search

One hundred and fifty-five college students completed questionnaires measuring explanatory style, general expectations for future good and bad events, specific expectations for future good and bad events, and depressive symptoms. Structural equation modeling confirmed the prediction of the attributional reformulation of learned helplessness theory that the link between stability and globality of explanatory style and depression is mediated by expectations.

Christopher Peterson; Robert S. Vaidya

2001-01-01

273

Student Expectations of Course and Instructor.  

ERIC Educational Resources Information Center

Investigates student expectations of themselves and their instructors by administering a precourse questionnaire to 393 introductory psychology students at Emporia State University (Kansas). Uses a postcourse questionnaire to determine how these expectations were met. Shows women and men had similar expectations. Contends results are useful to…

Becker, Angela H.; And Others

1990-01-01

274

Witten spinors on maximal, conformally flat hypersurfaces  

NASA Astrophysics Data System (ADS)

The boundary conditions that exclude zeros of the solutions of the Witten equation (and hence guarantee the existence of a 3-frame satisfying the so-called special orthonormal frame gauge conditions) are investigated. We determine the general form of the conformally invariant boundary conditions for the Witten equation, and find the boundary conditions that characterize the constant and the conformally constant spinor fields among the solutions of the Witten equations on compact domains in extrinsically and intrinsically flat, and on maximal, intrinsically globally conformally flat spacelike hypersurfaces, respectively. We also provide a number of exact solutions of the Witten equation with various boundary conditions (both at infinity and on inner or outer boundaries) that single out nowhere vanishing spinor fields on the flat, non-extreme Reissner-Nordström and Brill-Lindquist data sets. Our examples show that there is an interplay between the boundary conditions, the global topology of the hypersurface and the existence/non-existence of zeros of the solutions of the Witten equation.

Frauendiener, Jörg; Nester, James M.; Szabados, László B.

2011-09-01

275

Maximally localized Wannier functions: Theory and applications  

NASA Astrophysics Data System (ADS)

The electronic ground state of a periodic system is usually described in terms of extended Bloch orbitals, but an alternative representation in terms of localized “Wannier functions” was introduced by Gregory Wannier in 1937. The connection between the Bloch and Wannier representations is realized by families of transformations in a continuous space of unitary matrices, carrying a large degree of arbitrariness. Since 1997, methods have been developed that allow one to iteratively transform the extended Bloch orbitals of a first-principles calculation into a unique set of maximally localized Wannier functions, accomplishing the solid-state equivalent of constructing localized molecular orbitals, or “Boys orbitals” as previously known from the chemistry literature. These developments are reviewed here, and a survey of the applications of these methods is presented. This latter includes a description of their use in analyzing the nature of chemical bonding, or as a local probe of phenomena related to electric polarization and orbital magnetization. Wannier interpolation schemes are also reviewed, by which quantities computed on a coarse reciprocal-space mesh can be used to interpolate onto much finer meshes at low cost, and applications in which Wannier functions are used as efficient basis functions are discussed. Finally the construction and use of Wannier functions outside the context of electronic-structure theory is presented, for cases that include phonon excitations, photonic crystals, and cold-atom optical lattices.

Marzari, Nicola; Mostofi, Arash A.; Yates, Jonathan R.; Souza, Ivo; Vanderbilt, David

2012-10-01

276

Skeletal muscle vasodilatation during maximal exercise in health and disease  

PubMed Central

Maximal exercise vasodilatation results from the balance between vasoconstricting and vasodilating signals combined with the vascular reactivity to these signals. During maximal exercise with a small muscle mass the skeletal muscle vascular bed is fully vasodilated. During maximal whole body exercise, however, vasodilatation is restrained by the sympathetic system. This is necessary to avoid hypotension since the maximal vascular conductance of the musculature exceeds the maximal pumping capacity of the heart. Endurance training and high-intensity intermittent knee extension training increase the capacity for maximal exercise vasodilatation by 20–30%, mainly due to an enhanced vasodilatory capacity, as maximal exercise perfusion pressure changes little with training. The increase in maximal exercise vascular conductance is to a large extent explained by skeletal muscle hypertrophy and vascular remodelling. The vasodilatory capacity during maximal exercise is reduced or blunted with ageing, as well as in chronic heart failure patients and chronically hypoxic humans; reduced vasodilatory responsiveness and increased sympathetic activity (and probably, altered sympatholysis) are potential mechanisms accounting for this effect. Pharmacological counteraction of the sympathetic restraint may result in lower perfusion pressure and reduced oxygen extraction by the exercising muscles. However, at the same time fast inhibition of the chemoreflex in maximally exercising humans may result in increased vasodilatation, further confirming a restraining role of the sympathetic nervous system on exercise-induced vasodilatation. This is likely to be critical for the maintenance of blood pressure in exercising patients with a limited heart pump capacity.

Calbet, Jose A L; Lundby, Carsten

2012-01-01

277

Maximal Oxygen Uptake, Sweating and Tolerance to Exercise in the Heat  

NASA Technical Reports Server (NTRS)

The physiological mechanisms that facilitate acute acclimation to heat have not been fully elucidated, but the result is the establishment of a more efficient cardiovascular system to increase heat dissipation via increased sweating that allows the acclimated man to function with a cooler internal environment and to extend his performance. Men in good physical condition with high maximal oxygen uptakes generally acclimate to heat more rapidly and retain it longer than men in poorer condition. Also, upon first exposure trained men tolerate exercise in the heat better than untrained men. Both resting in heat and physical training in a cool environment confer only partial acclimation when first exposed to work in the heat. These observations suggest separate additive stimuli of metabolic heat from exercise and environmental heat to increase sweating during the acclimation process. However, the necessity of utilizing physical exercise during acclimation has been questioned. Bradbury et al. (1964) have concluded exercise has no effect on the course of heat acclimation since increased sweating can be induced by merely heating resting subjects. Preliminary evidence suggests there is a direct relationship between the maximal oxygen uptake and the capacity to maintain thermal regulation, particularly through the control of sweating. Since increased sweating is an important mechanism for the development of heat acclimation, and fit men have high sweat rates, it follows that upon initial exposure to exercise in the heat, men with high maximal oxygen uptakes should exhibit less strain than men with lower maximal oxygen uptakes. The purpose of this study was: (1) to determine if men with higher maximal oxygen uptakes exhibit greater tolerance than men with lower oxygen uptakes during early exposure to exercise in the heat, and (2) to investigate further the mechanism of the relationship between sweating and maximal work capacity.

Greenleaf, J. E.; Castle, B. L.; Ruff, W. K.

1972-01-01

278

Utility solar water heating workshops  

SciTech Connect

The objective of this project was to explore the problems and opportunities for utility participation with solar water heating as a DSM measure. Expected benefits from the workshops included an increased awareness and interest by utilities in solar water heating as well as greater understanding by federal research and policy officials of utility perspectives for purposes of planning and programming. Ultimately, the project could result in better information transfer, increased implementation of solar water heating programs, greater penetration of solar systems, and more effective research projects. The objective of the workshops was satisfied. Each workshop succeeded in exploring the problems and opportunities for utility participation with solar water heating as a DSM option. The participants provided a range of ideas and suggestions regarding useful next steps for utilities and NREL. According to evaluations, the participants believed the workshops were very valuable, and they returned to their utilities with new information, ideas, and commitment.

Barrett, L.B. (Barrett Consulting Associates, Inc., Colorado Springs, CO (United States))

1992-01-01

279

Maximizing power to constrain simple conceptual models  

NASA Astrophysics Data System (ADS)

Traditionally, hydrological models are calibrated to observables such as discharge or groundwater levels. However, in recent years more and more researchers recognize that catchments organize themselves, and there have been strong arguments for behavioral models (i.e. models that constrain their parameters by an organizing principle). The principle of Maximum Entropy Production (MEP) is an often mentioned candidate. But until now, only limited studies explore the use of this principle. In this study we explore the principle of maximum power (which is equivalent to MEP) to constrain the water partitioning in the unsaturated zone and link that to widely applied bucket models such as HBV. Maximum power (or MEP) only applies to systems that are in steady state. By only considering the yearly water balance, the system can be assumed to be in steady state. Therefore we limit ourselves to the unsaturated zone in which the partitioning between transpiration and runoff takes place. For each time step the matrix potential in the unsaturated zone has been determined. The matrix potential influences the driving gradients of both evapotranspiration and runoff to the stream. Power was then determined by multiplying the water flux with the gradient driving that flux. By varying the unsaturated hydraulic conductivity, soil depth and a shape factor accounting for the spatial variability in soil depth, power has been maximized. Since a catchment is never in steady state due to e.g. tectonic movement, only those parameter sets were considered that mimic the yearly water balance correctly. This study is one of the first studies that explore the principle of maximum Power (or MEP) to model real world catchments. It sheds light on its usefulness in hydrology and its limitation and it may bring the hydrological sciences a step further in understanding catchment behavior.

Westhoff, M.; Zehe, E.

2012-04-01

280

Rapid Expectation Adaptation during Syntactic Comprehension  

PubMed Central

When we read or listen to language, we are faced with the challenge of inferring intended messages from noisy input. This challenge is exacerbated by considerable variability between and within speakers. Focusing on syntactic processing (parsing), we test the hypothesis that language comprehenders rapidly adapt to the syntactic statistics of novel linguistic environments (e.g., speakers or genres). Two self-paced reading experiments investigate changes in readers’ syntactic expectations based on repeated exposure to sentences with temporary syntactic ambiguities (so-called “garden path sentences”). These sentences typically lead to a clear expectation violation signature when the temporary ambiguity is resolved to an a priori less expected structure (e.g., based on the statistics of the lexical context). We find that comprehenders rapidly adapt their syntactic expectations to converge towards the local statistics of novel environments. Specifically, repeated exposure to a priori unexpected structures can reduce, and even completely undo, their processing disadvantage (Experiment 1). The opposite is also observed: a priori expected structures become less expected (even eliciting garden paths) in environments where they are hardly ever observed (Experiment 2). Our findings suggest that, when changes in syntactic statistics are to be expected (e.g., when entering a novel environment), comprehenders can rapidly adapt their expectations, thereby overcoming the processing disadvantage that mistaken expectations would otherwise cause. Our findings take a step towards unifying insights from research in expectation-based models of language processing, syntactic priming, and statistical learning.

Fine, Alex B.; Jaeger, T. Florian; Farmer, Thomas A.; Qian, Ting

2013-01-01

281

Maximality-Based Structural Operational Semantics for Petri Nets  

NASA Astrophysics Data System (ADS)

The goal of this work is to exploit an implementable model, namely the maximality-based labeled transition system, which permits to express true-concurrency in a natural way without splitting actions on their start and end events. One can do this by giving a maximality-based structural operational semantics for the model of Place/Transition Petri nets in terms of maximality-based labeled transition systems structures.

Saïdouni, Djamel Eddine; Belala, Nabil; Bouneb, Messaouda

2009-03-01

282

HARDY-LITTLEWOOD MAXIMAL OPERATOR ON Lp(x)(R)  

Microsoft Academic Search

We consider Hardy-Littlewood maximal operator on the general Lebesgue space Lp(x)(Rn) with variable exponent. A sufficient condition on the function p is known for the boundedness of the maximal operator on Lp(x)(?) with an open bounded ? .O ur main aim is to find an additional condition to p to guarantee the boundedness of the maximal operator on Lp(x)(Rn). From

ALES NEKVINDA

283

Effect of Crowd Density on the Expected Number of Casualties in a Suicide Attack.  

National Technical Information Service (NTIS)

Utilizing elementary geometric and probability considerations, the author estimates the effect of crowd blocking in suicide bombing events. It is shown that the effect is quite significant. Beyond a certain threshold, the expected number of casualties dec...

M. Kress

2005-01-01

284

Biomass utilization  

SciTech Connect

Forty papers are presented in 6 sections: Biomass utilization - the concept; The raw material and its preparation; The structure and chemical composition of biomass; Conversion methods - biological; Conversion methods - thermochemical; and Engineering and economics in biomass utilization. Ten papers are of particular forestry interest: Forest inventories as the basis for a continuous monitoring of forest biomass resources (Cunia, T.); Aerial photo biomass equation (Kasile, J.); Forest biomass utilization in Greece (Tsoumis, C.); Mass propagation of selected trees for biomass by tissue culture (Venketeswaran, S. et al.); The anatomy, ultrastructure and chemical composition of wood (Coete, W.A.); Some structural characteristics of acid hydrolysis lignins (Papadopoulos, J.); Thermochemical routes to chemicals, fuels and energy from forestry and agricultural residues (Soltes, E.J.); Pyrolysis of wood wastes (Figueiredo, J.L. et al.); Efficient utilization of woody biomass: a cellulose-particleboard-synfuels model (Young, R.A.; Achmadi, S.); and Methanol from wood, a state of the art review (Beenackers, A.A.C.M.; Swaaij, W.P.M. van).

Coute, W.A. (ed.)

1983-01-01

285

Glary Utilities  

NSDL National Science Digital Library

Glary Utilities offers this free application to help users improve their system's performance and also protect their privacy. After installing the application, users can remove and back up faculty registry entries, along with offering a secure file deletion feature. This version is compatible with computers running Windows 98 and newer.

2008-01-01

286

Ash Utilization.  

National Technical Information Service (NTIS)

Contents: Production and utilization of ash in the United States; The inhibitory effect of fly ash with respect to the corrosion of steel in concretes; Fly ash concrete in buildings in Chicago; A review of ash specifications; Prediction of fly ash perform...

J. D. Spencer J. H. Faber N. H. Coates

1970-01-01

287

Effective Resource Utilization for Multiprocessor Join Execution  

Microsoft Academic Search

Conventional approaches to execution of database queries on general purpose multiprocessors attempt to maximize system throughput using inter-query parallelism with a fixed number of processors. Standard uniprocessor optimization techniques are used to minimize execution time of individual queries, Our approach is to increase performance by utilizing intra-query parallelism as well as minimizing overall resource requirements. Specifically, processor and tio bandwidth

Marguerite C. Murphy; Doron Rotem

1989-01-01

288

Violating Bell inequalities maximally for two d-dimensional systems  

SciTech Connect

We show the maximal violation of Bell inequalities for two d-dimensional systems by using the method of the Bell operator. The maximal violation corresponds to the maximal eigenvalue of the Bell operator matrix. The eigenvectors corresponding to these eigenvalues are described by asymmetric entangled states. We estimate the maximum value of the eigenvalue for large dimension. A family of elegant entangled states |{psi}>{sub app} that violate Bell inequality more strongly than the maximally entangled state but are somewhat close to these eigenvectors is presented. These approximate states can potentially be useful for quantum cryptography as well as many other important fields of quantum information.

Chen Jingling [Theoretical Physics Division, Chern Institute of Mathematics, Center for Combinatorics and LPMC, Nankai University, Tianjin 300071 (China); Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Wu Chunfeng; Oh, C. H. [Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Kwek, L. C. [Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Nanyang Technological University, National Institute of Education, 1, Nanyang Walk, Singapore 637616 (Singapore); Ge Molin [Theoretical Physics Division, Chern Institute of Mathematics, Center for Combinatorics and LPMC, Nankai University, Tianjin 300071 (China)

2006-09-15

289

On the way towards a generalized entropy maximization procedure  

NASA Astrophysics Data System (ADS)

We propose a generalized entropy maximization procedure, which takes into account the generalized averaging procedures and information gain definitions underlying the generalized entropies. This novel generalized procedure is then applied to Rényi and Tsallis entropies. The generalized entropy maximization procedure for Rényi entropies results in the exponential stationary distribution asymptotically for q?(0,1] in contrast to the stationary distribution of the inverse power law obtained through the ordinary entropy maximization procedure. Another result of the generalized entropy maximization procedure is that one can naturally obtain all the possible stationary distributions associated with the Tsallis entropies by employing either ordinary or q-generalized Fourier transforms in the averaging procedure.

Bagci, G. Baris; Tirnakli, Ugur

2009-08-01

290

Maximizing industrial infrastructure efficiency in Iceland  

NASA Astrophysics Data System (ADS)

As a consequence of the increasing aluminum production in Iceland, local processing of aluminum skimmings has become a feasible business opportunity. A recycling plant for this purpose was built in Helguvik on the Reykjanes peninsula in 2003. The case of the recycling plant reflects increased concern regarding environmental aspects of the industry. An interesting characteristic of this plant is the fact that it is run in the same facilities as a large fishmeal production installation. It is operated by the same personnel and uses—partly—the same equipment and infrastructure. This paper reviews the grounds for these decisions and the experience of this merger of a traditional fish melting industry and a more recent aluminum melting industry after 6 years of operation. The paper is written by the original entrepreneurs behind the company, who provide observations on how the aluminum industry in Iceland has evolved since the starting of Alur’s operation and what might be expected in the near future.

Ingason, Helgi Thor; Sigfusson, Thorsteinn I.

2010-08-01

291

Maximizing the utilization of computer-aided technology for fabrication of composite structures  

Microsoft Academic Search

The introduction of the computer in today's engineering environment presents new opportunities for the optimization of the product definition process. The certification effort on McDonnell Douglas Helicopter Company's MD 520N Program is used as a case study to show how the management of digital data can be used as a tool to dramatically reduce the cycle time of producing advanced

Glenn T. Pyle; Carlo S. Rao

1992-01-01

292

Maximizing the utilization of computer-aided technology for fabrication of composite structures  

NASA Astrophysics Data System (ADS)

The introduction of the computer in today's engineering environment presents new opportunities for the optimization of the product definition process. The certification effort on McDonnell Douglas Helicopter Company's MD 520N Program is used as a case study to show how the management of digital data can be used as a tool to dramatically reduce the cycle time of producing advanced composite structures. The MD 520N Product Definition Team used MDHC's Unigraphics 3-D CAD/CAM System to develop, design, fabricate, and test a production thruster assembly in just 74 days. This paper documents that effort and discusses the application this process may have in the normal production design environment.

Pyle, Glenn T.; Rao, Carlo S.

293

A sampling plan for conduit-flow karst springs: Minimizing sampling cost and maximizing statistical utility  

USGS Publications Warehouse

Analytical data for nitrate and triazines from 566 samples collected over a 3-year period at Pleasant Grove Spring, Logan County, KY, were statistically analyzed to determine the minimum data set needed to calculate meaningful yearly averages for a conduit-flow karst spring. Results indicate that a biweekly sampling schedule augmented with bihourly samples from high-flow events will provide meaningful suspended-constituent and dissolved-constituent statistics. Unless collected over an extensive period of time, daily samples may not be representative and may also be autocorrelated. All high-flow events resulting in a significant deflection of a constituent from base-line concentrations should be sampled. Either the geometric mean or the flow-weighted average of the suspended constituents should be used. If automatic samplers are used, then they may be programmed to collect storm samples as frequently as every few minutes to provide details on the arrival time of constituents of interest. However, only samples collected bihourly should be used to calculate averages. By adopting a biweekly sampling schedule augmented with high-flow samples, the need to continuously monitor discharge, or to search for and analyze existing data to develop a statistically valid monitoring plan, is lessened.Analytical data for nitrate and triazines from 566 samples collected over a 3-year period at Pleasant Grove Spring, Logan County, KY, were statistically analyzed to determine the minimum data set needed to calculate meaningful yearly averages for a conduit-flow karst spring. Results indicate that a biweekly sampling schedule augmented with bihourly samples from high-flow events will provide meaningful suspended-constituent and dissolved-constituent statistics. Unless collected over an extensive period of time, daily samples may not be representative and may also be autocorrelated. All high-flow events resulting in a significant deflection of a constituent from base-line concentrations should be sampled. Either the geometric mean or the flow-weighted average of the suspended constituents should be used. If automatic samplers are used, then they may be programmed to collect storm samples as frequently as every few minutes to provide details on the arrival time of constituents of interest. However, only samples collected bihourly should be used to calculate averages. By adopting a biweekly sampling schedule augmented with high-flow samples, the need to continuously monitor discharge, or to search for and analyze existing data to develop a statistically valid monitoring plan, is lessened.

Currens, J. C.

1999-01-01

294

Optimal Real-Time Pricing Algorithm Based on Utility Maximization for Smart Grid  

Microsoft Academic Search

In this paper, we consider a smart power infrastructure, where several subscribers share a common energy source. Each subscriber is equipped with an energy consumption controller (ECC) unit as part of its smart meter. Each smart meter is connected to not only the power grid but also a communication infrastructure such as a local area network. This allows two-way communication

Pedram Samadi; Amir-Hamed Mohsenian-Rad; Robert Schober; Vincent W. S. Wong; Juri Jatskevich

2010-01-01

295

Supplementing Corn-Soybean Meal Diets with Microbial Phytase Maximizes Phytate Phosphorus Utilization by Weanling Pigs  

Microsoft Academic Search

~~~~~~~ ~ ~ ~ ~ ABSTRACT: Two experiments were conducted mately 1,200 PU\\/g of BD. Estimated maximum with crossbred weanling pigs to determine the optimal responses of these measures in pigs fed phytase were 2 dietary supplement of AspergiZZus niger phytase ac- 90% compared with MDCaP. Pigs fed 1,250 PUlg of tivity to a low-P, corn-soybean meal basal diet (BD).

X. G. Lei; P. K. Ku; E. R. Millel; M. T. Yokoyama; D. E. Ullrey

2010-01-01

296

Cross-Layer Design of MIMO-Enabled WLANs With Network Utility Maximization  

Microsoft Academic Search

Wireless local area networks (WLANs) have become a ubiquitous high-speed data-access technology. The recent IEEE 802.11e standard provides quality-of-service (QoS) support, and the pending 802.11n standard further increases the transmission rate by using the multiple-input-multiple-output (MIMO) technique. Multiple antennas can be used to improve the performance gain by either increasing the transmission reliability through spatial diversity or increasing the transmission

Yuxia Lin; Vincent W. S. Wong

2009-01-01

297

Solving for Optimal Retirement Financial Plans by Maximizing a Discounted Habit Formation Utility Function.  

National Technical Information Service (NTIS)

With the increasing popularity of defined-benefit retirement plans, retiring individuals are looking for professional financial advice to help manage their nest eggs. Commonly prescribed generic 'one size fits all' rules of thumb such as the 4% Rule can c...

W. P. Johnson

2009-01-01

298

Ground truth spectrometry and imagery of eruption clouds to maximize utility of satellite imagery  

NASA Technical Reports Server (NTRS)

Field experiments with thermal imaging infrared radiometers were performed and a laboratory system was designed for controlled study of simulated ash clouds. Using AVHRR (Advanced Very High Resolution Radiometer) thermal infrared bands 4 and 5, a radiative transfer method was developed to retrieve particle sizes, optical depth and particle mass involcanic clouds. A model was developed for measuring the same parameters using TIMS (Thermal Infrared Multispectral Scanner), MODIS (Moderate Resolution Imaging Spectrometer), and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). Related publications are attached.

Rose, William I.

1993-01-01

299

Trend of Maximal Inspiratory Pressure in Mechanically Ventilated Patients: Predictors  

PubMed Central

INTRODUCTION It is known that mechanical ventilation and many of its features may affect the evolution of inspiratory muscle strength during ventilation. However, this evolution has not been described, nor have its predictors been studied. In addition, a probable parallel between inspiratory and limb muscle strength evolution has not been investigated. OBJECTIVE To describe the variation over time of maximal inspiratory pressure during mechanical ventilation and its predictors. We also studied the possible relationship between the evolution of maximal inspiratory pressure and limb muscle strength. METHODS A prospective observational study was performed in consecutive patients submitted to mechanical ventilation for > 72 hours. The maximal inspiratory pressure trend was evaluated by the linear regression of the daily maximal inspiratory pressure and a logistic regression analysis was used to look for independent maximal inspiratory pressure trend predictors. Limb muscle strength was evaluated using the Medical Research Council score. RESULTS One hundred and sixteen patients were studied, forty-four of whom (37.9%) presented a decrease in maximal inspiratory pressure over time. The members of the group in which maximal inspiratory pressure decreased underwent deeper sedation, spent less time in pressure support ventilation and were extubated less frequently. The only independent predictor of the maximal inspiratory pressure trend was the level of sedation (OR=1.55, 95% CI 1.003 – 2.408; p = 0.049). There was no relationship between the maximal inspiratory pressure trend and limb muscle strength. CONCLUSIONS Around forty percent of the mechanically ventilated patients had a decreased maximal inspiratory pressure during mechanical ventilation, which was independently associated with deeper levels of sedation. There was no relationship between the evolution of maximal inspiratory pressure and the muscular strength of the limb.

Caruso, Pedro; Carnieli, Denise Simao; Kagohara, Keila Harue; Anciaes, Adriana; Segarra, Jacqueline Santos; Deheinzelin, Daniel

2008-01-01

300

Predicting Problem Behaviors with Multiple Expectancies: Expanding Expectancy-Value Theory  

ERIC Educational Resources Information Center

Expectancy-value theory emphasizes the importance of outcome expectancies for behavioral decisions, but most tests of the theory focus on a single behavior and a single expectancy. However, the matching law suggests that individuals consider expected outcomes for both the target behavior and alternative behaviors when making decisions. In this…

Borders, Ashley; Earleywine, Mitchell; Huey, Stanley J.

2004-01-01

301

Novice Faculty: Encountering Expectations in Academia.  

ERIC Educational Resources Information Center

Six novice nursing faculty described their expectations of the teaching role and how they perceived expectations that other faculty and students had of them. Their stories revealed inadequacies in the way new faculty are prepared and mentored. (Contains 21 references.) (SK)

Siler, Bobbie B.; Kleiner, Catherine

2001-01-01

302

Rising Tides: Faculty Expectations of Library Websites  

ERIC Educational Resources Information Center

Looking at 2003-2009 LibQUAL+ responses at research-oriented universities in the United States, faculty library users report a significant and consistent rise in desires and expectations for library-provided online tools and websites, even as student user groups show declining or leveling expectations. While faculty, like students, also report…

Nicol, Erica Carlson; O'English, Mark

2012-01-01

303

Icelandic and American Students' Expectations about Counseling.  

ERIC Educational Resources Information Center

The Expectations about Counseling-Brief Form was administered to 261 Icelandic and 225 American undergraduates. Results of a multivariate analysis of covariance reveal that Icelanders had higher expectations about counselor expertise than did Americans. Results are discussed in terms of counselor roles and functions and the role of help seeking in…

Aegisdottir, Stefania; Gerstein, Lawrence H.

2000-01-01

304

Student Acceptance and Expectation of Sexual Assault  

Microsoft Academic Search

Male and female students’ attitudes regarding the acceptance and expectation of sexual assault were examined. Participants also completed Burt’s (1980) Rape Myth Acceptance ( RMA) Scale. Acceptance of sexual aggression can lead to the exoneration of the perpetrator, whereas expectations of sexual aggression can lead to victim blaming. A feminist perspective of rape, with a focus on sexual socialization, indicates

Marian M. Morry; Erica Winkler

2001-01-01

305

The College President: Expectations, Realities, and Myths.  

ERIC Educational Resources Information Center

Two speeches are presented: Expectations and Realities for the College President, by Joseph Kauffman, and Myths of the College Presidency, by Donald E. Walker. The first discusses the discrepancies between the expectations and realities in three areas: the relationship with boards of trustees, relations with central administration in the state…

Kauffman, Joseph F.; Walker, Donald E.

306

What Respondents Really Expect from Researchers  

ERIC Educational Resources Information Center

This article addresses the issue of falling response rates in telephone surveys. To better understand and maintain respondent goodwill, concepts of psychological contract and respondent expectations are introduced and explored. Results of the qualitative study show that respondent expectations are not only socially contingent but also…

Kolar, Tomaz; Kolar, Iztok

2008-01-01

307

Grief Experiences and Expectance of Suicide  

ERIC Educational Resources Information Center

Suicide is generally viewed as an unexpected cause of death. However, some suicides might be expected to a certain extent, which needs to be further studied. The relationships between expecting suicide, feeling understanding for the suicide, and later grief experiences were explored. In total, 142 bereaved participants completed the Grief…

Wojtkowiak, Joanna; Wild, Verena; Egger, Jos

2012-01-01

308

What to Expect Your First Year Teaching  

NSDL National Science Digital Library

This online book from the U.S. Department of Education covers topics vital to new teachers. Topics include getting support from administrators, what to expect from students and parents, and what should be expected in a new job. The book takes the form of narrative and interviews with new teachers.

Depaul, Amy

2005-03-06

309

Raising Expectations is Aim of New Effort  

ERIC Educational Resources Information Center

Researchers and policymakers agree that teachers' expectations of what their students can do can become self-fulfilling prophecies for children's academic performance. Yet while the "soft bigotry of low expectations" has become an education catchphrase, scholars and advocates are just beginning to explore whether it is possible to prevent such…

Sparks, Sarah D.

2010-01-01

310

Expectations of Vocational Teachers for Handicapped Students.  

ERIC Educational Resources Information Center

The study examined three components of the initial expectations of 66 secondary vocational teachers toward mainstreamed educable mentally retarded and learning disabled children. Among findings was that presence of the labels lowered the initial academic and behavioral expectations of teachers in the sample. (SB)

Minner, Sam

1982-01-01

311

Expectancy Theory in Media and Message Selection.  

ERIC Educational Resources Information Center

Argues for reversing emphasis on uses and gratifications research in favor of an expectancy model which holds that selection of a particular medium depends on (1) the expectation that the choice will be followed by a message of interest and (2) the importance of that message in satisfying user's values. (PD)

Van Leuven, Jim

1981-01-01

312

Parents' Role in Adolescents' Educational Expectations  

ERIC Educational Resources Information Center

The present study examined the extent to which mothers' and fathers' expectations for their offspring's future education, their level of education, and adolescents' academic achievement predict adolescents' educational expectations. To investigate this, 230 adolescents were examined twice while they were in comprehensive school (in the 7th and 9th…

Rimkute, Laura; Hirvonen, Riikka; Tolvanen, Asko; Aunola, Kaisa; Nurmi, Jari-Erik

2012-01-01

313

Course Expectations and Career Management Skills  

ERIC Educational Resources Information Center

Course completion and student satisfaction is likely to be influenced by how realistic the expectations of students are when they enroll. This report explores the idea that students' expectations would be more realistic if students have well developed career management competencies. Recent research argues that lack of information is not the…

Kennedy, Marnie L.; Haines, Ben

2008-01-01

314

Pace's Maxims for Homegrown Library Projects. Coming Full Circle  

ERIC Educational Resources Information Center

This article discusses six maxims by which to run library automation. The following maxims are discussed: (1) Solve only known problems; (2) Avoid changing data to fix display problems; (3) Aut viam inveniam aut faciam; (4) If you cannot make it yourself, buy something; (5) Kill the alligator closest to the boat; and (6) Just because yours is…

Pace, Andrew K.

2005-01-01

315

Cosmic Billiards with Painted Walls in Non Maximal Supergravities  

Microsoft Academic Search

The derivation of smooth cosmic billiard solutions by means of the compensator method, introduced by us sometimes ago, is extended to the case of supergravity with non maximal supersymmetry. Here a new key feature is provided by the non-maximal split nature of the scalar coset manifold. To deal with this, one has to consider the theory of Tits Satake projections

Pietro Fre; Floriana Gargiulo; Ksenya Rulik

316

Elliptical symmetric distribution based maximal margin classification for hyperspectral imagery  

Microsoft Academic Search

It has been verified that hyperspectral data is statistically characterized by elliptical symmetric distribution. Accordingly, we introduce the ellipsoidal discriminant boundaries and present an elliptical symmetric distribution based maximal margin (ESD-MM) classifier for hypespectral classification. In this method, the characteristic of elliptical symmetric distribution (ESD) of hyperspectral data is combined with the maximal margin rule. This strategy enables the ESD-MM

Lin He; Zhuliang Yu; Zhenghui Gu; Yuanqing Li

2011-01-01

317

One-Sided Continuous Dependence of Maximal Solutions.  

National Technical Information Service (NTIS)

Existence of a maximal solution is proved for a differential equation satisfying a one-sided variant of Caratheodory's condition. The maximal solution is shown to dominate all solutions of a very general differential inequality. Also a best-possible condi...

E. Schechter

1979-01-01

318

Optimal maximal ratio combining with correlated diversity branches  

Microsoft Academic Search

It is proved that a maximal ratio combiner operating on correlated branches and weighting the branch signals as though they were independent is optimal. It is also proved that performance measures of maximal ratio combining operating with correlated Rayleigh or Ricean fading input branches are identical to performance measures of an equivalent diversity system operating with independent and, in general,

Xiaofei Dong; Norman C. Beaulieu

2002-01-01

319

Minimal Length, Maximal Momentum and the Entropic Force Law  

NASA Astrophysics Data System (ADS)

Different candidates of quantum gravity proposal such as string theory, noncommutative geometry, loop quantum gravity and doubly special relativity, all predict the existence of a minimum observable length and/or a maximal momentum which modify the standard Heisenberg uncertainty principle. In this paper, we study the effects of minimal length and maximal momentum on the entropic force law formulated recently by E. Verlinde.

Nozari, Kourosh; Pedram, Pouria; Molkara, M.

2012-04-01

320

Preschoolers Can Recognize Violations of the Gricean Maxims  

ERIC Educational Resources Information Center

Grice ("Syntax and semantics: Speech acts", 1975, pp. 41-58, Vol. 3) proposed that conversation is guided by a spirit of cooperation that involves adherence to several conversational maxims. Three types of maxims were explored in the current study: 1) Quality, to be truthful; 2) Relation, to say only what is relevant to a conversation; and 3)…

Eskritt, Michelle; Whalen, Juanita; Lee, Kang

2008-01-01

321

Effect of Age and Other Factors on Maximal Heart Rate.  

ERIC Educational Resources Information Center

To reduce confusion regarding reported effects of age on maximal exercise heart rate, a comprehensive review of the relevant English literature was conducted. Data on maximal heart rate after exercising with a bicycle, a treadmill, and after swimming were analyzed with regard to physical fitness and to age, sex, and racial differences. (Authors/PP)

Londeree, Ben R.; Moeschberger, Melvin L.

1982-01-01

322

Revisiting the Greedy Approach to Submodular Set Function Maximization  

Microsoft Academic Search

We consider the problem of maximizing a nondecreasing submodular set function over various constraint structures. Specifically, we explore the performance of the greedy algorithm, and a related variant, the locally greedy algorithm in solving submodular function maximization problems. Most classic results on the greedy algorithm and its variant assume the existence of an optimal polynomial-time incremental oracle that identifies, in

Pranava R. Goundan; Andreas S. Schulz

323

Computing the viability kernel using maximal reachable sets  

Microsoft Academic Search

We present a connection between the viability kernel and maximal reachable sets. Current numerical schemes that compute the viability kernel suffer from a complexity that is exponential in the dimension of the state space. In contrast, extremely efficient and scalable techniques are available that compute maximal reachable sets. We show that under certain conditions these techniques can be used to

Shahab Kaynama; John Maidens; Meeko Oishi; Ian M. Mitchell; Guy A. Dumont

2012-01-01

324

Maximizing exposure therapy: An inhibitory learning approach.  

PubMed

Exposure therapy is an effective approach for treating anxiety disorders, although a substantial number of individuals fail to benefit or experience a return of fear after treatment. Research suggests that anxious individuals show deficits in the mechanisms believed to underlie exposure therapy, such as inhibitory learning. Targeting these processes may help improve the efficacy of exposure-based procedures. Although evidence supports an inhibitory learning model of extinction, there has been little discussion of how to implement this model in clinical practice. The primary aim of this paper is to provide examples to clinicians for how to apply this model to optimize exposure therapy with anxious clients, in ways that distinguish it from a 'fear habituation' approach and 'belief disconfirmation' approach within standard cognitive-behavior therapy. Exposure optimization strategies include 1) expectancy violation, 2) deepened extinction, 3) occasional reinforced extinction, 4) removal of safety signals, 5) variability, 6) retrieval cues, 7) multiple contexts, and 8) affect labeling. Case studies illustrate methods of applying these techniques with a variety of anxiety disorders, including obsessive-compulsive disorder, posttraumatic stress disorder, social phobia, specific phobia, and panic disorder. PMID:24864005

Craske, Michelle G; Treanor, Michael; Conway, Christopher C; Zbozinek, Tomislav; Vervliet, Bram

2014-07-01

325

Expectancy-Value Theory of Achievement Motivation.  

PubMed

We discuss the expectancy-value theory of motivation, focusing on an expectancy-value model developed and researched by Eccles, Wigfield, and their colleagues. Definitions of crucial constructs in the model, including ability beliefs, expectancies for success, and the components of subjective task values, are provided. These definitions are compared to those of related constructs, including self-efficacy, intrinsic and extrinsic motivation, and interest. Research is reviewed dealing with two issues: (1) change in children's and adolescents' ability beliefs, expectancies for success, and subjective values, and (2) relations of children's and adolescents' ability-expectancy beliefs and subjective task values to their performance and choice of activities. Copyright 2000 Academic Press. PMID:10620382

Wigfield; Eccles

2000-01-01

326

Approaching maximal performance of longitudinal beam compression in induction accelerator drivers  

SciTech Connect

Longitudinal beam compression occurs before final focus and fusion chamber beam transport and is a key process determining initial conditions for final focus hardware. Determining the limits for maximal performance of key accelerator components is an essential element of the effort to reduce driver costs. Studies directed towards defining the limits of final beam compression including considerations such as maximal available compression, effects of longitudinal dispersion and beam emittance, combining pulse-shaping with beam compression to reduce the total number of beam manipulators, etc., are given. Several possible techniques are illustrated for utilizing the beam compression process to provide the pulse shapes required by a number of targets. Without such capabilities to shape the pulse, an additional factor of two or so of beam energy would be required by the targets.

Mark, J.W.K.; Ho, D.D.M.; Brandon, S.T.; Chang, C.L.; Drobot, A.T.; Faltens, A.; Lee, E.P.; Krafft, G.A.

1986-09-24

327

Neurobiology of placebo effects: expectations or learning?  

PubMed

Contemporary learning theories suggest that conditioning is heavily dependent on the processing of prediction errors, which signal a discrepancy between expected and observed outcomes. This line of research provides a framework through which classical theories of placebo effects, expectations and conditioning, can be reconciled. Brain regions related to prediction error processing [anterior cingulate cortex (ACC), orbitofrontal cortex or the nucleus accumbens] overlap with those involved in placebo effects. Here we examined the possibility that the magnitude of objective neurochemical responses to placebo administration would depend on individual expectation-effectiveness comparisons. We show that such comparisons and not expectations per se predict behavioral placebo responses and placebo-induced activation of µ-opioid receptor-mediated neurotransmission in regions relevant to error detection (e.g. ACC). Expectations on the other hand were associated with greater µ-opioid system activation in the dorsolateral prefrontal cortex but not with greater behavioral placebo responses. The results presented aid the elucidation of molecular and neural mechanisms underlying the relationship between expectation-effectiveness associations and the formation of placebo responses, shedding light on the individual differences in learning and decision making. Expectation and outcome comparisons emerge as a cognitive mechanism that beyond reward associations appears to facilitate the formation and sustainability of placebo responses. PMID:23887819

Peciña, Marta; Stohler, Christian S; Zubieta, Jon-Kar

2014-07-01

328

Patterns of drug use and expectations in methadone patients.  

PubMed

Expectations about future behavior have been shown to have a positive relationship with subsequent behavior. For patients in drug treatment, recovery should manifest changes in drug use and in cognitive perceptions of being able to refrain from use. The present study identified latent patterns of the longitudinal relationship between drug use expectation and illegal drug use during treatment. Latent variable mixture modeling identified three patterns of change over successive 3-month intervals during treatment: Improvers (48%), Decliners (33%), and Continuing Users (19%). The sample consisted of 497 patients in community-based outpatient methadone treatment. The utility of the latent patterns was shown through their relationship to treatment engagement, where Continuing Users had lower counseling rapport and time in treatment. These latent patterns also differed on drug use measures at follow-up. Additional analyses of expectations with measures of opioid use, cocaine use, or criminality yielded similar latent patterns. Expectations about future drug use were found to be a useful measure of cognitive change corresponding to drug use change. Its potential as a brief treatment management tool is noted. PMID:17218066

Joe, George W; Flynn, Patrick M; Broome, Kirk M; Simpson, D Dwayne

2007-08-01

329

Expectations and Outcomes of Prolonged Mechanical Ventilation  

PubMed Central

Objective: Prolonged mechanical ventilation (PMV) provision is increasing markedly despite poor patient outcomes. Misunderstanding prognosis in the PMV decision making process could provide an explanation to this phenomenon. Therefore, we aimed to compare PMV decision makers' expectations for long-term patient outcomes with prospectively observed outcomes. Design, Setting, and Patients: 126 patients undergoing PMV, their surrogates, and their intensive care unit physicians were enrolled consecutively (total n=378) at an academic medical center between April 2006 and April 2007 and followed prospectively for one year. Measurements: Participants were interviewed at the time of tracheostomy placement about their expectations for one-year patient survival, functional status, and quality of life. These expectations were then compared to observed one-year outcomes measured with validated questionnaires. Results: One-year follow up was 100%, with the exception of patient death or cognitive inability to complete interviews. At one year, only 11 (9%) patients were alive and independent of major functional status limitations. Most surrogates reported high baseline expectations for one-year patient survival (117 [93%]), functional status (90 [71%]), and quality of life (105 [83%]). In contrast, fewer physicians described high expectations for survival (54 [43%]), functional status (7 [6%]), and quality of life (5 [4%]). Surrogate-physician pair concordance in expectations was poor (all ?<0.08), as was their accuracy in outcome prediction (range 23-44%). Just 33 (26%) surrogates reported that physicians discussed what to expect for patients' likely future survival, general health, and caregiving needs. Conclusions: One-year patient outcomes for PMV patients were significantly worse than expected by patients' surrogates and physicians. Lack of prognostication about outcomes, discordance between surrogates and physicians about potential outcomes, and surrogates' unreasonably optimistic expectations appear to be potentially modifiable deficiencies in surrogate-physician interactions.

Cox, Christopher E.; Martinu, Tereza; Sathy, Shailaja J.; Clay, Alison S.; Chia, Jessica; Gray, Alice L.; Olsen, Maren K.; Govert, Joseph A.; Carson, Shannon S.; Tulsky, James A.

2009-01-01

330

What to Expect After a Heart Transplant  

MedlinePLUS

... on Twitter. What To Expect After a Heart Transplant Staying in the Hospital The amount of time ... if you have too many side effects. Managing Transplant Medicines and Their Side Effects You'll have ...

331

What to Expect during a Heart Transplant  

MedlinePLUS

... NHLBI on Twitter. What To Expect During a Heart Transplant Just before heart transplant surgery, the patient will ... are not replaced as part of the surgery. Heart Transplant Figure A shows where the diseased heart is ...

332

What to Expect during Heart Surgery  

MedlinePLUS

... the NHLBI on Twitter. What To Expect During Heart Surgery Heart surgery is done in a hospital, ... surgery, takes about 3–6 hours. Traditional Open-Heart Surgery For this type of surgery, you'll ...

333

Expected Supernovae Rates and Gravitational Waves Detection.  

National Technical Information Service (NTIS)

Data available in the Kraan-Korteweg catalog of 2810 nearby galaxies is used to evaluate the expected rate of supernovae (SN) events according to distance. Three different statistics and two virgocentric flow models for determinating distance of galaxies ...

P. Rapagnani

1989-01-01

334

What To Expect Before a Lung Transplant  

MedlinePLUS

... NHLBI on Twitter. What To Expect Before a Lung Transplant If you get into a medical center's ... friends also can offer support. When a Donor Lung Becomes Available OPTN matches donor lungs to recipients ...

335

What to Expect During a Lung Transplant  

MedlinePLUS

... NHLBI on Twitter. What To Expect During a Lung Transplant Just before lung transplant surgery, you will ... airway and its blood vessels to your heart. Lung Transplant The illustration shows the process of a ...

336

Rational Expectations Model of Financial Contagion.  

National Technical Information Service (NTIS)

We develop a multiple asset rational expectations model of securities prices to explain the determinants of nancial market contagion. Our primary focus is on con- tagion through the cross-market hedging (rebalancing) of shared macroeconomic risks. Through...

L. E. Kodres M. Pritsker

1999-01-01

337

Expected errors computed from effective bits  

SciTech Connect

This memorandum has two purposes. The first is to review how we can calculate error bars for a given data set from the effective-bits measurements. The second is to outline how we can use the error bars to quantify expected errors in linear fits to data, integrated data, and power spectral densities computed from data. The expected errors for these quantities are calculated using standard statistics and probability techniques.

Tunnell, T.

1990-10-22

338

Maximizing nearest-neighbor entanglement in finitely correlated qubit chains  

SciTech Connect

We consider translationally invariant states of an infinite one-dimensional chain of qubits or spin-(1/2) particles. We maximize the entanglement shared by nearest neighbors via a variational approach based on finitely correlated states. We find an upper bound of nearest-neighbor concurrence equal to C=0.434 095 which is 0.09% away from the bound C{sub W}=0.434 467 obtained by a completely different procedure. The obtained state-maximizing nearest-neighbor entanglement seems to approximate the maximally entangled mixed states. Further we investigate in detail several other properties of the so-obtained optimal state.

Hiesmayr, Beatrix C.; Narnhofer, Heide [Institut fuer Theoretische Physik, Universitaet Wien, Boltzmanngasse 5, 1090 Vienna (Austria); Koniorczyk, Matyas [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, 1525 Budapest (Hungary); Institute of Physics, University of Pecs, Ifjusag utja 6, 7624 Pecs (Hungary)

2006-03-15

339

Taxation and life expectancy in Western Europe.  

PubMed

With the exception of Denmark, life expectancy in Western Europe has shown a significant increase over the last decades. During that period of time overall taxation has increased in most of the countries, especially in Denmark. We, therefore, examined whether taxation could influence life expectancy in Western Europe. We used information on the sum of income tax and employees' social contribution in percentage of gross wage earnings from the OECD database and data on disability adjusted life expectancy at birth from the World Health Organization database. We arbitrarily only included countries with populations in excess of 4 millions and thereby excluded smaller countries where tax exemption is part of the national monetary policy. We found that disability adjusted life expectancy at birth was inversely correlated to the total tax burden in Western Europe. We speculate whether a threshold exists where high taxes exert a negative influence on life expectancy despite increased welfare spending. The study suggests that tax burden should be considered among the multiple factors influencing life expectancy. PMID:15242031

Bagger, P J

2004-06-01

340

Determination of Maximal Aerobic Power during Upper Body Exercise.  

National Technical Information Service (NTIS)

The purpose of this investigation was to evaluate four protocols for their effectiveness in eliciting maximal aerobic power (peak VO2) during arm crank exercise. Comparisons were made between: (1) a continuous (CON) and an intermittent (INT) protocol (bot...

M. N. Sawka M. E. Foley N. A. Pimental M. M. Toner K. B. Pandolf

1982-01-01

341

Rational maximizing by humans (Homo sapiens) in an ultimatum game.  

PubMed

In the human mini-ultimatum game, a proposer splits a sum of money with a responder. If the responder accepts, both are paid. If not, neither is paid. Typically, responders reject inequitable distributions, favoring punishing over maximizing. In Jensen et al.'s (Science 318:107-109, 2007) adaptation with apes, a proposer selects between two distributions of raisins. Despite inequitable offers, responders often accept, thereby maximizing. The rejection response differs between the human and ape versions of this game. For humans, rejection is instantaneous; for apes, it requires 1 min of inaction. We replicate Jensen et al.'s procedure in humans with money. When waiting 1 min to reject, humans favor punishing over maximizing; however, when rejection requires 5 min of inaction, humans, like apes, maximize. If species differences in time horizons are accommodated, Jensen et al.'s ape data are reproducible in humans. PMID:20130945

Smith, Phillip; Silberberg, Alan

2010-07-01

342

Cliqueing--A Technique for Producing Maximally Connected Clusters  

ERIC Educational Resources Information Center

Explains a technique whereby a large data base may be automatically classified into maximally connected clusters called cliques. The data base used is a section of United States patents. (Author/ MBR)

Gerson, Gordon M.

1978-01-01

343

A throughput-maximizing facility planning and layout model  

Microsoft Academic Search

This paper presents a throughput-maximizing algorithm for facility planning and layout of flexible manufacturing systems. It uses a computationally efficient mean-value analysis model to analyse system configurations, and extends the methodology of CRAFT in layout planning.

HENRY CO; ALBERT WU; ARNOLD REISMAN

1989-01-01

344

Maximizing Your Investment in Building Automation System Technology.  

ERIC Educational Resources Information Center

Discusses how organizational issues and system standardization can be important factors that determine an institution's ability to fully exploit contemporary building automation systems (BAS). Further presented is management strategy for maximizing BAS investments. (GR)

Darnell, Charles

2001-01-01

345

Maximal slicing of D-dimensional spherically symmetric vacuum spacetime  

SciTech Connect

We study the foliation of a D-dimensional spherically symmetric black-hole spacetime with D{>=}5 by two kinds of one-parameter families of maximal hypersurfaces: a reflection-symmetric foliation with respect to the wormhole slot and a stationary foliation that has an infinitely long trumpetlike shape. As in the four-dimensional case, the foliations by the maximal hypersurfaces avoid the singularity irrespective of the dimensionality. This indicates that the maximal slicing condition will be useful for simulating higher-dimensional black-hole spacetimes in numerical relativity. For the case of D=5, we present analytic solutions of the intrinsic metric, the extrinsic curvature, the lapse function, and the shift vector for the foliation by the stationary maximal hypersurfaces. These data will be useful for checking five-dimensional numerical-relativity codes based on the moving puncture approach.

Nakao, Ken-ichi; Abe, Hiroyuki [Department of Mathematics and Physics, Graduate School of Science, Osaka City University, Osaka 558-8585 (Japan); Yoshino, Hirotaka [Department of Physics, University of Alberta, Edmonton, Alberta, T6G 2G7 (Canada); Shibata, Masaru [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

2009-10-15

346

Magellan Project: Evolving Enhanced Operations Efficiency to Maximize Science Value.  

National Technical Information Service (NTIS)

Magellan has been one of NASA's most successful spacecraft, returning more science data than all planetary spacecraft combined. The Magellan Spacecraft Team (SCT) has maximized the science return with innovative operational techniques to overcome anomalie...

A. R. Cheuvront J. C. Neuman J. F. Mckinney

1994-01-01

347

Existence of a Maximal Solution for Quasimonotone Elliptic Systems.  

National Technical Information Service (NTIS)

Systems of elliptic equations are studied by using a consequence of the maximum principle, namely the 'sub-supersolution method'. Existence of a maximal solution between a subsolution and a supersolution is obtained under the following two conditions: F i...

E. Mitidieri G. Sweers

1993-01-01

348

A cycle ergometer test of maximal aerobic power  

Microsoft Academic Search

Summary  An indirect test of maximal aerobic power (IMAP) was evaluated in 31 healthy male subjects by comparing it with a direct treadmill measurement of maximal aerobic power (\\u000a$$\\\\dot V$$\\u000aO2 max), with the prediction of \\u000a$$\\\\dot V$$\\u000aO2 max from heart rate during submaximal exercise on a cycle ergometer using åstrand's nomogram, with the British Army's Basic Fitness Test

W. S. Myles; R. J. Toft

1982-01-01

349

Total body fat does not influence maximal aerobic capacity  

Microsoft Academic Search

OBJECTIVE: The objective of this study was to examine the influence of body weight and body composition on aspects of aerobic fitness. Our hypothesis was that increased body weight, specifically increased fat mass (FM), would not limit VO2max relative to fat-free mass (FFM), but would reduce maximal and sub-maximal VO2max relative to body weight.DESIGN: We used data from two ongoing

M Goran; DA Fields; GR Hunter; SL Herd; RL Weinsier

2000-01-01

350

Maximal-Ratio Eigen-Combining for Smarter Antenna Arrays  

Microsoft Academic Search

In typical mobile wireless scenarios, signals are received with power azimuth angle spectrum (p.a.s.) of variable azimuth angle spread (AS). Therefore, conventional maximum average signal-to-noise ratio beamforming (BF) or maximal- ratio combining (MRC) may not necessarily be effective in terms of performance or signal processing complexity. A newer, more flexible, approach, called maximal-ratio eigen-combining (MREC) is analyzed and found to

Constantin Siriteanu; Steven D. Blostein

2007-01-01

351

Testing the nonlinear flux Ansatz for maximal supergravity  

NASA Astrophysics Data System (ADS)

We put to test the recently proposed nonlinear flux Ansatz for maximal supergravity in 11 dimensions, which gives the seven-dimensional flux in terms of the scalars and pseudoscalars of maximal N=8 supergravity, by considering a number of nontrivial solutions of gauged supergravity for which the higher-dimensional solutions are known. These include the G2 and SU(4)- invariant stationary points. The examples considered constitute a very nontrivial check of the Ansatz, which it passes with remarkable success.

Godazgar, Hadi; Godazgar, Mahdi; Nicolai, Hermann

2013-04-01

352

A Role for Dopamine in Temporal Decision Making and Reward Maximization in Parkinsonism  

PubMed Central

Converging evidence implicates striatal dopamine (DA) in reinforcement learning, such that DA increases enhance “Go learning” to pursue actions with rewarding outcomes, whereas DA decreases enhance “NoGo learning” to avoid non-rewarding actions. Here we test whether these effects apply to the response time domain. We employ a novel paradigm which requires the adjustment of response times to a single response. Reward probability varies as a function of response time, whereas reward magnitude changes in the opposite direction. In the control condition, these factors exactly cancel, such that the expected value across time is constant (CEV). In two other conditions, expected value increases (IEV) or decreases (DEV), such that reward maximization requires either speeding up (Go learning) or slowing down (NoGo learning) relative to the CEV condition. We tested patients with Parkinson's disease (depleted striatal DA levels) on and off dopaminergic medication, compared with age-matched controls. While medicated, patients were better at speeding up in the DEV relative to CEV conditions. Conversely, nonmedicated patients were better at slowing down to maximize reward in the IEV condition. These effects of DA manipulation on cumulative Go/NoGo response time adaptation were captured with our a priori computational model of the basal ganglia, previously applied only to forced-choice tasks. There were also robust trial-to-trial changes in response time, but these single trial adaptations were not affected by disease or medication and are posited to rely on extrastriatal, possibly prefrontal, structures.

Moustafa, Ahmed A.; Cohen, Michael X.; Sherman, Scott J.; Frank, Michael J.

2011-01-01

353

Combustion Research Aboard the ISS Utilizing the Combustion Integrated Rack and Microgravity Science Glovebox  

NASA Technical Reports Server (NTRS)

The Physical Sciences Research Program of NASA sponsors a broad suite of peer-reviewed research investigating fundamental combustion phenomena and applied combustion research topics. This research is performed through both ground-based and on-orbit research capabilities. The International Space Station (ISS) and two facilities, the Combustion Integrated Rack and the Microgravity Science Glovebox, are key elements in the execution of microgravity combustion flight research planned for the foreseeable future. This paper reviews the Microgravity Combustion Science research planned for the International Space Station implemented from 2003 through 2012. Examples of selected research topics, expected outcomes, and potential benefits will be provided. This paper also summarizes a multi-user hardware development approach, recapping the progress made in preparing these research hardware systems. Within the description of this approach, an operational strategy is presented that illustrates how utilization of constrained ISS resources may be maximized dynamically to increase science through design decisions made during hardware development.

Sutliff, Thomas J.; Otero, Angel M.; Urban, David L.

2002-01-01

354

EXPECT: Explicit Representations for Flexible Acquisition  

NASA Technical Reports Server (NTRS)

To create more powerful knowledge acquisition systems, we not only need better acquisition tools, but we need to change the architecture of the knowledge based systems we create so that their structure will provide better support for acquisition. Current acquisition tools permit users to modify factual knowledge but they provide limited support for modifying problem solving knowledge. In this paper, the authors argue that this limitation (and others) stem from the use of incomplete models of problem-solving knowledge and inflexible specification of the interdependencies between problem-solving and factual knowledge. We describe the EXPECT architecture which addresses these problems by providing an explicit representation for problem-solving knowledge and intent. Using this more explicit representation, EXPECT can automatically derive the interdependencies between problem-solving and factual knowledge. By deriving these interdependencies from the structure of the knowledge-based system itself EXPECT supports more flexible and powerful knowledge acquisition.

Swartout, BIll; Gil, Yolanda

1995-01-01

355

Experience and Choice Shape Expected Aversive Outcomes  

PubMed Central

The value assigned to aversive events is susceptible to contextual influences. Here, we asked whether a change in the valuation of negative events is reflected in an altered neuronal representation of their expected aversive outcome. We show that experiencing an aversive event in the past, and choosing to experience it in the future, reduces its aversive value. This psychological change is mirrored in an altered neural representation of aversive value in the caudate nucleus, and anterior cingulate cortex (ACC). Our findings indicate that subcortical regions known to track expected value such as the caudate nucleus, together with anterior cingulate cortical regions implicated in emotional modulation, mediate a re-valuation in expectancies of aversive states. The results provide a striking example of a contextual sensitivity in how the brain ascribes value to events, in a manner that may foster resilience in the face of adversity.

Sharot, Tali; Shiner, Tamara; Dolan, Raymond J

2010-01-01

356

Major League Baseball Players' Life Expectancies*  

PubMed Central

Objective We examine the importance of anthropometric and performance measures, and age, period, and cohort effects in explaining life expectancies among major league baseball (MLB) players over the past century. Methods We use discrete time hazard models to calculate life tables with covariates with data from Total Baseball, a rich source of information on all players who played in the major league. Results Compared to 20-year-old U.S. males, MLB players can expect almost five additional years of life. Height, weight, handedness, and player ratings are unassociated with the risk of death in this population of highly active and successful adults. Career length is inversely associated with the risk of death, likely because those who play longer gain additional incomes, physical fitness, and training. Conclusions Our results indicate improvements in life expectancies with time for all age groups and indicate possible improvements in longevity in the general U.S. population.

Saint Onge, Jarron M.; Rogers, Richard G.; Krueger, Patrick M.

2009-01-01

357

Maximizing Kolmogorov Complexity for accurate and robust bright field cell segmentation  

PubMed Central

Background Analysis of cellular processes with microscopic bright field defocused imaging has the advantage of low phototoxicity and minimal sample preparation. However bright field images lack the contrast and nuclei reporting available with florescent approaches and therefore present a challenge to methods that segment and track the live cells. Moreover, such methods must be robust to systemic and random noise, variability in experimental configuration, and the multiple unknowns in the biological system under study. Results A new method called maximal-information is introduced that applies a non-parametric information theoretic approach to segment bright field defocused images. The method utilizes a combinatorial optimization strategy to select specific defocused images from each image stack such that set complexity, a Kolmogorov complexity measure, is maximized. Differences among these selected images are then applied to initialize and guide a level set based segmentation algorithm. The performance of the method is compared with a recent approach that uses a fixed defocused image selection strategy over an image data set of embryonic kidney cells (HEK 293T) from multiple experiments. Results demonstrate that the adaptive maximal-information approach significantly improves precision and recall of segmentation over the diversity of data sets. Conclusions Integrating combinatorial optimization with non-parametric Kolmogorov complexity has been shown to be effective in extracting information from microscopic bright field defocused images. The approach is application independent and has the potential to be effective in processing a diversity of noisy and redundant high throughput biological data.

2014-01-01

358

Utility-Optimal Medium Access Control: Reverse and Forward Engineering  

Microsoft Academic Search

This paper analyzes and designs medium access control (MAC) protocols for wireless ad-hoc networks through the network utility maximization (NUM) framework. We first reverse-engineer the current exponential backoff (EB) type of MAC protocols such as the BEB (binary exponential backoff) in the IEEE 802.11 standard through a non-cooperative game- theoretic model. This MAC protocol is shown to be implicitly maximizing,

Jang-won Lee; Mung Chiang; A. Robert Calderbank

2006-01-01

359

What respondents really expect from researchers.  

PubMed

This article addresses the issue of falling response rates in telephone surveys. To better understand and maintain respondent goodwill, concepts of psychological contract and respondent expectations are introduced and explored. Results of the qualitative study show that respondent expectations are not only socially contingent but also ego-expressive, utilitarian, pleasurable, and epistemic by nature. Although results are reassuring in terms of commercialization of the psychological contract, they indicate some radical changes that are needed for the respondents to accept its continuation. The article discusses several practical and theoretical implications of such changes and suggests a series of corresponding propositions aimed at facilitating and inspiring future developments in this field. PMID:18591708

Kolar, Tomaz; Kolar, Iztok

2008-08-01

360

Great expectations. Eating expectancies as mediators of reinforcement sensitivity and eating.  

PubMed

Eating expectancies are proposed as cognitive pathways linking reinforcement (reward and punishment) sensitivities and the tendency to over-eat in response to appetitive and emotional cues. In Study One (N=243 university women) explicit eating expectancies were tested as potential mediators of reinforcement sensitivities and eating styles. Broadly, expectancies that eating alleviates negative affect/boredom mediated both reward and punishment sensitivity and emotional eating. The expectancy that eating is pleasurable and rewarding mediated reward sensitivity and external eating. In Study Two (N=109), using an implicit eating expectancy task, reward sensitivity and external eating was mediated via positive expectancy statements, notably, that eating is pleasurable and rewarding. Reward sensitivity and emotional eating was mediated specifically by expectancies that eating manages boredom. Punishment sensitivity was not associated with any implicit expectancies. Findings support the role of expectancies as cognitive mediators in the relationship between reinforcement sensitivities and emotionally-driven versus externally-driven eating styles. However, the largely appetitive implicit expectancies task only supported an association with reward sensitivity. PMID:23932947

Hennegan, Julie M; Loxton, Natalie J; Mattar, Ameerah

2013-12-01

361

Moving multiple sinks through wireless sensor networks for lifetime maximization.  

SciTech Connect

Unattended sensor networks typically watch for some phenomena such as volcanic events, forest fires, pollution, or movements in animal populations. Sensors report to a collection point periodically or when they observe reportable events. When sensors are too far from the collection point to communicate directly, other sensors relay messages for them. If the collection point location is static, sensor nodes that are closer to the collection point relay far more messages than those on the periphery. Assuming all sensor nodes have roughly the same capabilities, those with high relay burden experience battery failure much faster than the rest of the network. However, since their death disconnects the live nodes from the collection point, the whole network is then dead. We consider the problem of moving a set of collectors (sinks) through a wireless sensor network to balance the energy used for relaying messages, maximizing the lifetime of the network. We show how to compute an upper bound on the lifetime for any instance using linear and integer programming. We present a centralized heuristic that produces sink movement schedules that produce network lifetimes within 1.4% of the upper bound for realistic settings. We also present a distributed heuristic that produces lifetimes at most 25:3% below the upper bound. More specifically, we formulate a linear program (LP) that is a relaxation of the scheduling problem. The variables are naturally continuous, but the LP relaxes some constraints. The LP has an exponential number of constraints, but we can satisfy them all by enforcing only a polynomial number using a separation algorithm. This separation algorithm is a p-median facility location problem, which we can solve efficiently in practice for huge instances using integer programming technology. This LP selects a set of good sensor configurations. Given the solution to the LP, we can find a feasible schedule by selecting a subset of these configurations, ordering them via a traveling salesman heuristic, and computing feasible transitions using matching algorithms. This algorithm assumes sinks can get a schedule from a central server or a leader sink. If the network owner prefers the sinks make independent decisions, they can use our distributed heuristic. In this heuristic, sinks maintain estimates of the energy distribution in the network and move greedily (with some coordination) based on local search. This application uses the new SUCASA (Solver Utility for Customization with Automatic Symbol Access) facility within the PICO (Parallel Integer and Combinatorial Optimizer) integer programming solver system. SUCASA allows rapid development of customized math programming (search-based) solvers using a problem's natural multidimensional representation. In this case, SUCASA also significantly improves runtime compared to implementations in the ampl math programming language or in perl.

Petrioli, Chiara (Universita di Roma); Carosi, Alessio (Universita di Roma); Basagni, Stefano (Northeastern University); Phillips, Cynthia Ann

2008-01-01

362

Transient hovering performance of hummingbirds under conditions of maximal loading.  

PubMed

Maximal load-lifting capacities of six ruby-throated hummingbirds (Archilochus colubris) were determined under conditions of burst performance. Mechanical power output under maximal loading was then compared with maximal hovering performance in hypodense gas mixtures of normodense air and heliox. The maximal load lifted was similar at air temperatures of 5 and 25 degrees C, and averaged 80% of body mass. The duration of load-lifting was brief, of the order of 1 s, and was probably sustained via phosphagen substrates. Under maximal loading, estimates of muscle mass-specific mechanical power output assuming perfect elastic energy storage averaged 206 W kg-1, compared with 94 W kg-1 during free hovering without loading. Under conditions of limiting performance in hypodense mixtures, maximal mechanical power output was much lower (131 W kg-1, five birds) but was sustained for longer (4 s), demonstrating an inverse relationship between the magnitude and duration of maximum power output. In free hovering flight, stroke amplitude and wingbeat frequency varied in inverse proportion between 5 and 25 degrees C, suggesting thermoregulatory contributions by the flight muscles. Stroke amplitude under conditions of maximal loading reached a geometrical limit at slightly greater than 180 degrees. Previous studies of maximum performance in flying animals have estimated mechanical power output using a simplified actuator disk model without a detailed knowledge of wingbeat frequency and stroke amplitude. The present load-lifting results, together with actuator disc estimates of induced power derived from hypodense heliox experiments, are congruent with previous load-lifting studies of maximum flight performance. For ruby-throated hummingbirds, the inclusion of wingbeat frequency and stroke amplitude in a more detailed aerodynamic model of hovering yields values of mechanical power output 34% higher than previous estimates. More generally, the study of performance limits in flying animals necessitates careful specification of behavioral context as well as quantitative determination of wing and body kinematics. PMID:9100364

Chai, P; Chen, J S; Dudley, R

1997-03-01

363

Muscle function in men and women during maximal eccentric exercise.  

PubMed

This study assessed muscle fatigue patterns of the elbow flexors in untrained men and women to determine if sex differences exist during acute maximal eccentric exercise. High-intensity eccentric exercise is often used by athletes to elicit gains in muscle strength and size gains. Development of fatigue during this type of exercise can increase risk of injury; therefore, it is important to understand fatigue patterns during eccentric exercise to minimize injury risk exposure while still promoting training effects. While many isometric exercise studies have demonstrated that women show less fatigue, the patterns of fatigue during purely eccentric exercise have not been assessed in men and women. Based on the lack of sex differences in overall strength loss immediately post-eccentric exercise, it was hypothesized that women and men would have similar relative fatigue pattern responses (i.e., change from baseline) during a single bout of maximal eccentric exercise. Forty-six subjects (24 women and 22 men) completed 5 sets of 10 maximal eccentric contractions on an isokinetic dynamometer. Maximal voluntary isometric contraction strength was assessed at baseline and immediately following each exercise set. Maximal eccentric torque and contractile properties (i.e., contraction time, work, half relaxation time, and maximal rate of torque development) were calculated for each contraction. Men and women demonstrated similar relative isometric (32% for men and 39% for women) and eccentric (32% for men and 39% for women) fatigue as well as similar deficits in work done and rates of torque development and relaxation during exercise (p > 0.05). Untrained men and women displayed similar relative responses in all measures of muscle function during a single bout of maximal eccentric exercise of the elbow flexors. Thus, there is no reason to suspect that women may be more vulnerable to fatigue-related injury. PMID:18545170

Hubal, Monica J; Rubinstein, Scott R; Clarkson, Priscilla M

2008-07-01

364

Macroeconomics after Two Decades of Rational Expectations.  

ERIC Educational Resources Information Center

Discusses real business cycle analysis, growth theory, and other economic concepts in the context of the rational expectations revolution in macroeconomics. Focuses on post-1982 research. Concludes that the rejuvenation of growth analysis is an encouraging development because it could lead to changes in welfare policy. (CFR)

McCallum, Bennett T.

1994-01-01

365

Analytic Derivatives for Linear Rational Expectations Models  

Microsoft Academic Search

This paper sets out the analytic solution for the calculation of exact derivatives in linear rational expectations models with reference to the optimal simple rule problem. We argue that there are substantial computational advantages of using analytic derivatives and compare the likely computational costs of using approximate and exact derivatives when calculating optimal coefficients for simple feedback rules. A specific

Andrew P. Blake

2004-01-01

366

How Students Verify Conjectures: Teachers' Expectations  

ERIC Educational Resources Information Center

Eight teachers were interviewed concerning how students verify conjectures. The study is a sequel to a previous study, "How Students Verify Conjectures" [Bergqvist, T. (2000). "How students verify conjectures." "Research reports in Mathematics Education" 3]. Teachers' expectations of students' reasoning and performance are examined, and also how…

Bergqvist, Tomas

2005-01-01

367

Outcome Expectancies and Risk-Taking Behavior  

Microsoft Academic Search

One explanation for risk-taking behavior despite warnings about the dangers is that anticipated positive consequences outweigh possible negative outcomes. In a five-part investigation, a new questionnaire was developed to assess outcome expectancies for the potential consequences of involvement in a variety of risky activities. Conceptual and methodological limitations of previously available questionnaires were addressed and content, construct, and criterion validity

Kim Fromme; Elizabeth C. Katz; Kathy Rivet

1997-01-01

368

What to Expect After a Lung Transplant  

MedlinePLUS

... NHLBI on Twitter. What To Expect After a Lung Transplant Recovery in the Hospital After lung transplant surgery, you'll go to the hospital's ... take slow, deep breaths. You also may have lung function tests that use a regular spirometer. This ...

369

Young Infants' Expectations about Hidden Objects  

ERIC Educational Resources Information Center

Infants aged 3-5 months (mean of approximately 4 months) were given a novel anticipatory looking task to test object permanence understanding. They were trained to expect an experimenter to retrieve an object from behind a transparent screen upon hearing a cue (''Doors up, here comes the hand''). The experimenter then hid the object behind one of…

Ruffman, Ted; Slade, Lance; Redman, Jessica

2005-01-01

370

Accessing alcohol expectancy networks through semantic priming  

Microsoft Academic Search

Cognitive theories of alcohol use have suggested that information pertinent to an individuals' experience with alcohol is acquired and stored in a semantic network of expectancies regarding the effects of alcohol. Semantic priming using a lexical decision task has been used to access memory processes within a semantic network. The present study involved screening 40 individuals with heavy current drinking

Luke W Galen

1996-01-01

371

Measuring Bubble Expectations and Investor Confidence  

Microsoft Academic Search

This paper presents evidence on attitude changes among investors in the US stock market. Two basic attitudes are explored: bubble expectations and investor confidence. Semiannual time-series indicators of these attitudes are presented for US stock market institutional investors based on questionnaire survey results 1989 1998, from surveys that I have derived in collaboration with Fumiko Kon-Ya and Yoshiro Tsutsui. Five

Robert J. Shiller

1999-01-01

372

Ownership, Investor Protection and Earnings Expectations  

Microsoft Academic Search

Abstract:?This study examines the interactive influence of corporate ownership, corporate governance and investor protection on the incorporation of current value shocks in the accounting earnings of European companies. This influence is investigated not only by means of the association between current news and current earnings but also with respect to the association of the same news with expected future earnings,

Christina Dargenidou; Stuart McLeay; Ivana Raonic

2007-01-01

373

Expected Linear 3-Dimensional Voronoi Diagram Algorithm.  

National Technical Information Service (NTIS)

Let S be a set of n sites chosen independently from a uniform distribution in a cube in 3-dimensional Euclidean space. In the paper, an expected O(n) algorithm for constructing the Voronoi diagram for S together with numerical results obtained from an imp...

J. Bernal

1990-01-01

374

Remote Library Users: Needs and Expectations.  

ERIC Educational Resources Information Center

Discusses remote library users in an academic environment. Highlights include user needs and expectations; user satisfaction; service to remote customers in nonlibrary environments, such as industry; the distance-learning context; student demographics; distance learning and library services; course design; and a case study at De Paul University.…

Cooper, Rosemarie; Dempsey, Paula R.; Menon, Vanaja; Millson-Martula, Christopher

1998-01-01

375

Expecting Too Much of Performance Pay?  

ERIC Educational Resources Information Center

Pay for performance is not a new idea, and reformers should not ignore the dismal record of merit pay over the past century. Initially adopted with a flourish of expectations during several waves of popularity in the past, every plan eventually fell into disuse. These plans proved to be unexpectedly costly and cumbersome to run. They often…

Johnson, Susan Moore; Papay, John P.

2010-01-01

376

Enhanced Expectancies Improve Performance Under Pressure  

PubMed Central

Beyond skill, beliefs in requisite abilities and expectations can affect performance. This experiment examined effects of induced perceptions of ability to perform well under generic situations of challenge. Participants (N?=?31) first completed one block of 20 trials on a throwing accuracy task. They then completed questionnaires ostensibly measuring individual differences in the ability to perform under pressure. Enhanced-expectancy group participants were told that they were well-suited to perform under pressure, while the control group received neutral information. Subsequently, all participants completed another block of 20 trials on the throwing task, with their performance videotaped and under the assumption that they could secure a prize for themselves and a paired participant with successful performance. Both groups had similar accuracy scores on the first trial block. The enhanced-expectancy group significantly increased their throwing accuracy in the higher-pressure situation (second block), whereas the control group showed no change in performance. Furthermore, beliefs regarding performance under challenge predicted throwing accuracy on the second block. The present findings provide evidence that enhancing individuals’ generic expectancies regarding performance under pressure can affect their motor performance.

McKay, Brad; Lewthwaite, Rebecca; Wulf, Gabriele

2012-01-01

377

Training Therapists about Client Expectations of Psychotherapy.  

ERIC Educational Resources Information Center

Research has indicated that premature termination of therapy is sometimes due to a conflict in goal and outcome expectations between therapists and family members of clients. The present study requested both therapists and parents of child clients to complete questionnaires to determine if there is congruence between therapist and parental…

Soley, Georgia; Marshall, Renee; Chambliss, Catherine

378

What to Expect in the Emergency Room  

MedlinePLUS Videos and Cool Tools

English - What to Expect in the Emergency Room 2 min 20 sec To Listen to the Audio or Read/Print/Save the Handout, Click on a Picture Below To Download These Files, Right Click the Mouse and Choose "Save link as...." Audio Mobile ...

379

Using expect to Automate System Administration Tasks  

Microsoft Academic Search

UNIX system administration often involves programs designed only for interactive use. Many such programs (passwd, su, etc.) cannot be placed into shell scripts. Some programs (fsck, dump, etc.) are not specifically interactive, but have poor support for automated use. expect is a program which can \\

Don Libes

1990-01-01

380

Helpful and Harmful Expectations of Premarital Interventions  

Microsoft Academic Search

Despite the demonstrated effectiveness of premarital programs, estimates indicate that only 30% of couples use these services. This study examined the helpful and harmful aspects of premarital programs that may encourage or discourage participation. As expected, participants identified improved communication and problem solving skills as most beneficial. Disclosing secrets or past relationship issues that threaten the stability of the relationship

Carlos E. Valiente; Catherine J. Belanger; Ana U. Estrada

2002-01-01

381

Athletes' expectations with regard to officiating competence  

Microsoft Academic Search

This study aimed to identify the cues upon which athletes rely when developing their expectations with regard to the competence of sports officials and to examine the sources of information, which are given priority in different kinds of sport (i.e. team, racquet and fighting sports). A questionnaire – the Athlete Perception of Sports Officials Questionnaire (APSO-Q) – was developed in

Fabrice Dosseville; Sylvain Laborde; Marjorie Bernier

2012-01-01

382

Inverse momentum expectation values for hydrogenic systems  

SciTech Connect

By using the Fourier transforms of the general hydrogenic bound state wave functions (as ultraspherical polynomials), one may find expectation values of arbitrary functions of momentum p. In this manner the effect of a reciprocity perturbation b/p can be evaluated for all hydrogenic states.

Delbourgo, R.; Elliott, D. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, GPO, Hobart, Tasmania 7001 (Australia)

2009-06-15

383

Reproductive longevity and increased life expectancy  

Microsoft Academic Search

Background: female life expectancy in developed countries has increased by 30 years in the twentieth century. Aim: to determine if there has been an increase in reproductive longevity. Methods: we analysed age-specific fertility data from birth statistics for the USA, Canada, Japan, France, Sweden, the UK and Australia. Results: since 1940, birth rates for women aged 35 and over have

JACOB A. BRODY; M ARK D. GRANT; L AWRENCE J. FRATESCHI; SUSAN C. MILLER

384

Expectations and Experiences of Substitute Teachers  

ERIC Educational Resources Information Center

This article explores the expectations of support for and the experiences of substitute teachers in an urban school division in Saskatchewan. Data were collected in semistructured interviews with seven substitute teachers. The purpose of the study was to explore how substitute teachers frame their professional experiences and construct their roles…

Duggleby, Patricia; Badali, Sal

2007-01-01

385

Children's Physical Appearance and Adult Expectations.  

ERIC Educational Resources Information Center

Caregivers' expectancies and behaviors in relationship to young handicapped children were investigated in this paper. Two studies were conducted in an attempt to answer three questions: (1) How will caregivers respond to the young handicapped child? (2) Do the child's stimulus characteristics, such as physical appearance, create biases in…

Feeg, Veronica DeCarolis; Peters, Donald L.

386

Demystify Learning Expectations to Address Grade Inflation  

ERIC Educational Resources Information Center

This article describes the subject of "grade inflation," a reference to educators giving higher grades to student work than their expectations for student achievement warrant. Of the many reasons why this practice happens, Hodges specifically discusses inflating grades as "a natural consequence" when the faculty really…

Hodges, Linda C.

2014-01-01

387

Adolescent expectations of early death predict young adult socioeconomic status.  

PubMed

Among adolescents, expectations of early death have been linked to future risk behaviors. These expectations may also reduce personal investment in education and training, thereby lowering adult socioeconomic status attainment. The importance of socioeconomic status is highlighted by pervasive health inequities and dramatic differences in life expectancy among education and income groups. The objectives of this study were to investigate patterns of change in perceived chances of living to age 35 (Perceived Survival Expectations; PSE), predictors of PSE, and associations between PSE and future socioeconomic status attainment. We utilized the U.S. National Longitudinal Study of Adolescent Health (Add Health) initiated in 1994-1995 among 20,745 adolescents in grades 7-12 with follow-up interviews in 1996 (Wave II), 2001-2002 (Wave III) and 2008 (Wave IV; ages 24-32). At Wave I, 14% reported ?50% chance of living to age 35 and older adolescents reported lower PSE than younger adolescents. At Wave III, PSE were similar across age. Changes in PSE from Wave I to III were moderate, with 89% of respondents reporting no change (56%), one level higher (22%) or one level lower (10%) in a 5-level PSE variable. Higher block group poverty rate, perceptions that the neighborhood is unsafe, and less time in the U.S. (among the foreign-born) were related to low PSE at Waves I and III. Low PSE at Waves I and III predicted lower education attainment and personal earnings at Wave IV in multinomial logistic regression models controlling for confounding factors such as previous family socioeconomic status, individual demographic characteristics, and depressive symptoms. Anticipation of an early death is prevalent among adolescents and predictive of lower future socioeconomic status. Low PSE reported early in life may be a marker for worse health trajectories. PMID:22405687

Nguyen, Quynh C; Hussey, Jon M; Halpern, Carolyn T; Villaveces, Andres; Marshall, Stephen W; Siddiqi, Arjumand; Poole, Charles

2012-05-01

388

Home Care Technology Through an Ability Expectation Lens  

PubMed Central

Home care is on the rise, and its delivery is increasingly reliant on an expanding variety of health technologies ranging from computers to telephone “health apps” to social robots. These technologies are most often predicated on expectations that people in their homes (1) can actively interact with these technologies and (2) are willing to submit to the action of the technology in their home. Our purpose is to use an “ability expectations” lens to bring together, and provide some synthesis of, the types of utility and disadvantages that can arise for people with disabilities in relation to home care technology development and use. We searched the academic databases Scopus, Web of Science, EBSCO ALL, IEEE Xplore, and Compendex to collect articles that had the term “home care technology” in the abstract or as a topic (in the case of Web of Science). We also used our background knowledge and related academic literature pertaining to self-diagnosis, health monitoring, companionship, health information gathering, and care. We examined background articles and articles collected through our home care technology search in terms of ability expectations assumed in the presentation of home care technologies, or discussed in relation to home care technologies. While advances in health care support are made possible through emerging technologies, we urge critical examination of such technologies in terms of implications for the rights and dignity of people with diverse abilities. Specifically, we see potential for technologies to result in new forms of exclusion and powerlessness. Ableism influences choices made by funders, policy makers, and the public in the development and use of home health technologies and impacts how people with disabilities are served and how useful health support technologies will be for them. We urge continued critical examination of technology development and use according to ability expectations, and we recommend increasing incorporation of participatory design processes to counteract potential for health support technology to render people with disabilities technologically excluded and powerless.

2014-01-01

389

Adolescent Expectations of Early Death Predict Young Adult Socioeconomic Status  

PubMed Central

Among adolescents, expectations of early death have been linked to future risk behaviors. These expectations may also reduce personal investment in education and training, thereby lowering adult socioeconomic status attainment. The importance of socioeconomic status is highlighted by pervasive health inequities and dramatic differences in life expectancy among education and income groups. The objectives of this study were to investigate patterns of change in perceived chances of living to age 35 (Perceived Survival Expectations; PSE), predictors of PSE, and associations between PSE and future socioeconomic status attainment. We utilized the U.S. National Longitudinal Study of Adolescent Health (Add Health) initiated in 1994-95 among 20,745 adolescents in grades 7-12 with follow-up interviews in 1996 (Wave II), 2001-02 (Wave III) and 2008 (Wave IV; ages 24-32). At Wave I, 14% reported ? 50% chance of living to age 35 and older adolescents reported lower PSE than younger adolescents. At Wave III, PSE were similar across age. Changes in PSE from Wave I to III were moderate, with 89% of respondents reporting no change (56%), one level higher (22%) or one level lower (10%) in a 5-level PSE variable. Higher block group poverty rate, perceptions that the neighborhood is unsafe, and less time in the U.S. (among the foreign-born) were related to low PSE at Waves I and III. Low PSE at Waves I and III predicted lower education attainment and personal earnings at Wave IV in multinomial logistic regression models controlling for confounding factors such as previous family socioeconomic status, individual demographic characteristics, and depressive symptoms. Anticipation of an early death is prevalent among adolescents and predictive of lower future socioeconomic status. Low PSE reported early in life may be a marker for worse health trajectories.

Nguyen, Quynh C.; Hussey, Jon M.; Halpern, Carolyn T.; Villaveces, Andres; Marshall, Stephen W.; Siddiqi, Arjumand; Poole, Charles

2013-01-01

390

Home care technology through an ability expectation lens.  

PubMed

Home care is on the rise, and its delivery is increasingly reliant on an expanding variety of health technologies ranging from computers to telephone "health apps" to social robots. These technologies are most often predicated on expectations that people in their homes (1) can actively interact with these technologies and (2) are willing to submit to the action of the technology in their home. Our purpose is to use an "ability expectations" lens to bring together, and provide some synthesis of, the types of utility and disadvantages that can arise for people with disabilities in relation to home care technology development and use. We searched the academic databases Scopus, Web of Science, EBSCO ALL, IEEE Xplore, and Compendex to collect articles that had the term "home care technology" in the abstract or as a topic (in the case of Web of Science). We also used our background knowledge and related academic literature pertaining to self-diagnosis, health monitoring, companionship, health information gathering, and care. We examined background articles and articles collected through our home care technology search in terms of ability expectations assumed in the presentation of home care technologies, or discussed in relation to home care technologies. While advances in health care support are made possible through emerging technologies, we urge critical examination of such technologies in terms of implications for the rights and dignity of people with diverse abilities. Specifically, we see potential for technologies to result in new forms of exclusion and powerlessness. Ableism influences choices made by funders, policy makers, and the public in the development and use of home health technologies and impacts how people with disabilities are served and how useful health support technologies will be for them. We urge continued critical examination of technology development and use according to ability expectations, and we recommend increasing incorporation of participatory design processes to counteract potential for health support technology to render people with disabilities technologically excluded and powerless. PMID:24956581

Wolbring, Gregor; Lashewicz, Bonnie

2014-01-01

391

Integrated life sciences technology utilization development program  

NASA Technical Reports Server (NTRS)

The goal of the TU program was to maximize the development of operable hardware and systems which will be of substantial benefit to the public. Five working prototypes were developed, and a meal system for the elderly is now undergoing evaluation. Manpower utilization is shown relative to the volume of requests in work for each month. The ASTP mobile laboratories and post Skylab bedrest study are also described.

1975-01-01

392

5 CFR 9701.406 - Setting and communicating performance expectations.  

Code of Federal Regulations, 2010 CFR

...performance plans, and other measures of performance. Such expectations include those...and respect for others. (c) Performance expectations may take the form...assignment, including expectations regarding the...timeliness, and/or other expected...

2010-01-01

393

Expected utility theory and prospect theory: one wedding and a decent funeral  

Microsoft Academic Search

Choice behavior is typically evaluated by assuming that the data is generated by one latent decision-making process or another.\\u000a What if there are two (or more) latent decision-making processes generating the observed choices? Some choices might then\\u000a be better characterized as being generated by one process, and other choices by the other process. A finite mixture model\\u000a can be used

Glenn W. Harrison; E. Elisabet Rutström

2009-01-01

394

THE INFLUENCE OF A COST-BENEFIT FUNCTION ON THE SUPPLY OF ECONOMIC CRIMES: A SPECIFIC TEST OF THE PROFIT MAXIMIZING THESIS  

Microsoft Academic Search

Most utilitarian theories assume that people are rational and tend to favor activities which maximize profits and minimize losses. Hence, when the gains associated with illegal behavior outweigh the costs, the volume of crime is expected to increase. Most macro-social research based on this perspective examines the effects of only one piece of information that informs the decision to violate

John K. Cochran; Mitchell B. Chamlin

1992-01-01

395

Light-cone formulation of maximally supersymmetric theories in superspace  

NASA Astrophysics Data System (ADS)

Maximally supersymmetric theories are discussed in four dimensions in the light-cone superspace formalism. We derive the symmetry generators of N = 4 Super Yang-Mills theory which contains maximal spin-one in four dimensions, and show that the on-shell Hamiltonian of the theory can be written as a quadratic form of a fermionic superfield. With maximal spin two, we explore how the non-linear on-shell E7(7) symmetry of N = 8 Supergravity in four dimensions can be realized on the light-cone, and find a remarkable result that in this light-cone gauge, all the physical fields, including the graviton, transform under E7(7) . We then derive the dynamical supersymmetry transformations to order kappa 2 by requiring the coset E7(7)/ SU(8) to commute with the super-Poincare group.

Kim, Sung-Soo

396

Atrial natriuretic factor responses to submaximal and maximal exercise.  

PubMed Central

The aim of this study was to evaluate and compare the plasma concentration of atrial natriuretic factor (ANF), K+, Na+, blood lactate, heart rate, and blood pressure in moderately trained women. Ten healthy women were studied on a cycle ergometer during 20 min of constant submaximal and maximal exercise, as well as during recovery. The ANF concentration was determined by radioimmunoassay. The results show that, except for Na+, all the other variables increased significantly with an increase in the duration and intensity of the exercise (P < 0.05, P < 0.001). In recovery, the values fell (P < 0.01, P < 0.001). Submaximal and maximal exercise both cause increases in ANF and this increase is due to the duration and intensity of exercise. However, maximal exercise, rather than submaximal exercise, is the major stimulus for the concentration of plasma ANF. ANF concentration may be a useful test for evaluating the releasing function of ANF in the heart.

Mandroukas, K; Zakas, A; Aggelopoulou, N; Christoulas, K; Abatzides, G; Karamouzis, M

1995-01-01

397

Young infants have biological expectations about animals  

PubMed Central

What are the developmental origins of our concept of animal? There has long been controversy concerning this question. At issue is whether biological reasoning develops from earlier forms of reasoning, such as physical and psychological reasoning, or whether from a young age children endow animals with biological properties. Here we demonstrate that 8-mo-old infants already expect novel objects they identify as animals to have insides. Infants detected a violation when an object that was self-propelled and agentive (but not an object that lacked one or both of these properties) was revealed to be hollow. Infants also detected a violation when an object that was self-propelled and furry (but not an object that lacked one or both of these properties) either was shown to be hollow or rattled (when shaken) as although mostly hollow. Young infants’ expectations about animals’ insides may serve as a foundation for the development of more advanced biological knowledge.

Setoh, Peipei; Wu, Di; Baillargeon, Renee; Gelman, Rochel

2013-01-01

398

Faculty Expectations and Development: The Tenure Case  

NASA Astrophysics Data System (ADS)

Professionals seeking careers in academia should understand the tenure process, and how to prepare successfully for the evaluations linked to the tenure decision. This chapter offers suggestions for persons pursuing tenure-track faculty positions in the discipline of food science. The first promotion process in academia (i.e., from assistant professor to associate professor) is typically linked to tenure consideration. The focus of this chapter is explaining tenure, tenure expectations, resources for guidance, how to manage the process, and how to prepare the tenure and promotion document. While most people are fearful of the promotion and tenure process, this fear and apprehension can be minimized by understanding the process and its expectations, and having good advice to follow to help ensure success.

Nielsen, S. Suzanne

399

Institutional Research: What Should We Expect? Defining and Exceeding Campus Expectations. AIR 1995 Annual Forum Paper.  

ERIC Educational Resources Information Center

Expectations and roles of institutional researchers in higher education institutions are considered, as well as the question of what a research office should expect from its institution. A performance monitoring system for the assessment and continuous improvement of institutional research is also proposed. Ways that institutional research can be…

Clagett, Craig A.; Kerr, Helen S.

400

Teachers' Expectations of Teacher-Student Interaction: Complementary and Distinctive Expectancy Patterns  

ERIC Educational Resources Information Center

In this study it is investigated what student responses teachers expect in particular teacher behaviour vignettes, and whether experience and gender produce differences in expectations. Teacher behaviour vignettes were presented to teachers (N = 46), who described the student responses they anticipated. Anticipated student responses were then…

de Jong, R. J.; van Tartwijk, J.; Verloop, N.; Veldman, I.; Wubbels, T.

2012-01-01

401

What Do Patients Expect from Their Physicians?  

PubMed Central

Background: To identify the most important expectations that patients have from their physicians. Methods: We collected data from 199 hospitalized and 201 ambulatory patients (response rates 88% and 93% respectively). We used random sampling for selection of hospitalized patients and systematic sampling for the ambulatory ones. The questionnaire consisted of 18 different expectation items categorized in 5 domains. The participants scored each item from 1 to 9 using a VAS scale and ranked domains based on their importance. We analyzed the data using univariate and regression analyses. Results: Among the ambulatory patients, the mean±standard error of the most important expectations was as follows: competency (8.9±0.01), courteousness (8.8±0.04), consultation in case of need (8.8±0.4), clear explanation of the disease (8.8±0.05) and attentiveness (8.8±0.04). In hospitalized patients, the following items were the most important: competency (8.4±0.08), courteousness (8.4±0.09), availability of physician (8.4±0.09), consultation in case of need (8.2±0.11), setting following appointments (8.2±0.1), and disease follow-up (8.2±0.09). In both groups, the most important domain of expectations was “competency and quality of care” followed by “availability” in hospitalized and “giving information and patient autonomy” among ambulatory patients. Conclusions: Our findings are similar to what reported in the literature from other countries and cultures. In addition to physician expertise and knowledge, patients value giving information and efficient doctor-patient relationship.

Dormohammadi, T; Asghari, F; Rashidian, A

2010-01-01

402

First Contact: Expectations of Beginning Astronomy Students  

NASA Astrophysics Data System (ADS)

Three hundred seven undergraduate students enrolled in Introductory Astronomy were surveyed at the beginning of class to determine their expectations for course content. The course serves as a survey of astronomy for non-science majors and is a distribution course for general education core requirements. The course has no prerequisites, meets three times each week for 50 minutes, and represents three semester credit hours. The university catalog describes the course with the title "PHYSICS 101 - Mysteries of the Sky" and the official course description is: a survey of the struggle to understand the Universe and our place therein. The structure, growth, methods, and limitations of science will be illustrated using the development of astronomy as a vehicle. Present day views of the Universe are presented. Two questions were asked as open response items: What made you decide to take this course? and What do you expect to learn in this course? The reasons that students cited to take the course, in order of frequency, were: interested in astronomy, interesting or fun sounding course, required general education fulfillment, recommendation by peer. Secondary reasons cited were required for major or minor, general interest in science, and was available in the schedule. Tertiary reasons listed were recommendation by advisor or orientation leader, inflate grade point average, and heard good things about the teacher. The students' expectations about what they would learn in the course were numerous. The most common objects listed, in order of frequency, were: stars, constellations, planets, galaxies, black holes, solar system, comets, galaxies, asteroids, moon, and Sun. More interesting were the aspects not specifically related to astronomy. These were weather, atmosphere, UFOs and the unexplained, generally things in the sky. A mid-course survey suggests that students expected to learn more constellations and that the topics would be less in-depth.

Lacey, T. L.; Slater, T. F.

1999-05-01

403

expect: Scripts for Controlling Interactive Processes  

Microsoft Academic Search

: Contemporary shells provide minimal control (starting, stopping,etc) over programs, leaving interaction up to users. This means that you cannot runsome programs non-interactively, such as passwd. Some programs can be run noninteractivelybut only with a loss of flexibility, such as fsck. This is where the toolbuildingphilosophy of UNIX begins to break down. expect crosses this line, solvinga number of long-standing

Don Libes

1991-01-01

404

Implicit Temporal Expectation Attenuates Auditory Attentional Blink  

Microsoft Academic Search

Attentional blink (AB) describes a phenomenon whereby correct identification of a first target impairs the processing of a second target (i.e., probe) nearby in time. Evidence suggests that explicit attention orienting in the time domain can attenuate the AB. Here, we used scalp-recorded, event-related potentials to examine whether auditory AB is also sensitive to implicit temporal attention orienting. Expectations were

Dawei Shen; Claude Alain

2012-01-01

405

Cardiovascular consequences of bed rest: effect on maximal oxygen uptake  

NASA Technical Reports Server (NTRS)

Maximal oxygen uptake (VO2max) is reduced in healthy individuals confined to bed rest, suggesting it is independent of any disease state. The magnitude of reduction in VO2max is dependent on duration of bed rest and the initial level of aerobic fitness (VO2max), but it appears to be independent of age or gender. Bed rest induces an elevated maximal heart rate which, in turn, is associated with decreased cardiac vagal tone, increased sympathetic catecholamine secretion, and greater cardiac beta-receptor sensitivity. Despite the elevation in heart rate, VO2max is reduced primarily from decreased maximal stroke volume and cardiac output. An elevated ejection fraction during exercise following bed rest suggests that the lower stroke volume is not caused by ventricular dysfunction but is primarily the result of decreased venous return associated with lower circulating blood volume, reduced central venous pressure, and higher venous compliance in the lower extremities. VO2max, stroke volume, and cardiac output are further compromised by exercise in the upright posture. The contribution of hypovolemia to reduced cardiac output during exercise following bed rest is supported by the close relationship between the relative magnitude (% delta) and time course of change in blood volume and VO2max during bed rest, and also by the fact that retention of plasma volume is associated with maintenance of VO2max after bed rest. Arteriovenous oxygen difference during maximal exercise is not altered by bed rest, suggesting that peripheral mechanisms may not contribute significantly to the decreased VO2max. However reduction in baseline and maximal muscle blood flow, red blood cell volume, and capillarization in working muscles represent peripheral mechanisms that may contribute to limited oxygen delivery and, subsequently, lowered VO2max. Thus, alterations in cardiac and vascular functions induced by prolonged confinement to bed rest contribute to diminution of maximal oxygen uptake and reserve capacity to perform physical work.

Convertino, V. A.

1997-01-01

406

Learning what to expect (in visual perception)  

PubMed Central

Expectations are known to greatly affect our experience of the world. A growing theory in computational neuroscience is that perception can be successfully described using Bayesian inference models and that the brain is “Bayes-optimal” under some constraints. In this context, expectations are particularly interesting, because they can be viewed as prior beliefs in the statistical inference process. A number of questions remain unsolved, however, for example: How fast do priors change over time? Are there limits in the complexity of the priors that can be learned? How do an individual’s priors compare to the true scene statistics? Can we unlearn priors that are thought to correspond to natural scene statistics? Where and what are the neural substrate of priors? Focusing on the perception of visual motion, we here review recent studies from our laboratories and others addressing these issues. We discuss how these data on motion perception fit within the broader literature on perceptual Bayesian priors, perceptual expectations, and statistical and perceptual learning and review the possible neural basis of priors.

Series, Peggy; Seitz, Aaron R.

2013-01-01

407

The climate is not what you expect  

NASA Astrophysics Data System (ADS)

Prevailing definitions of climate are not much different from "the climate is what you expect, the weather is what you get". Using a variety of sources including reanalyses and paleo data, and aided by notions and analysis techniques from Nonlinear Geophysics, we argue that this dictum is fundamentally wrong. In addition to the weather and climate, there is a qualitatively distinct intermediate regime extending over a factor of ? 1000 in scale. For example, mean temperature fluctuations increase up to about 5 K at 10 days (the lifetime of planetary structures), then decrease to about 0.2 K at 30 years, and then increase again to about 5 K at glacial-interglacial scales. Both deterministic GCM's with fixed forcings ("control runs") and stochastic turbulence-based models reproduce the first two regimes, but not the third. The middle regime is thus a kind of "macroweather" not "high frequency climate". Averaging macroweather over periods increasing to ? 30 yrs yields apparently converging values: macroweather is "what you expect". Macroweather averages over ?30 years have the lowest variability, they yield well defined "climate states" and justify the otherwise ad hoc "climate normal" period. However, moving to longer periods, these states increasingly fluctuate: just as with the weather, the climate changes in an apparently unstable manner; the climate is not what you expect. Similarly, we may categorize climate forcings according to whether their fluctuations decrease or increase with scale and this has important implications for GCM's and for climate change and climate predictions.

Lovejoy, Shaun; Schertzer, Daniel

2013-04-01

408

Compound Channels, Transition Expectations, and Liftings  

SciTech Connect

In Section 1 we introduce the notion of lifting as a generalization of the notion of compound state introduced in [21] and [22] and we show that this notion allows a unified approach to the problems of quantum measurement and of signal transmission through quantum channels. The dual of a linear lifting is a transition expectation in the sense of [3] and we characterize those transition expectations which arise from compound states in the sense of [22]. In Section 2 we characterize those liftings whose range is contained in the closed convex hull of product states and we prove that the corresponding quantum Markov chains [2] are uniquely determined by a classical generalization of both the quantum random walks of [4] and the locally diagonalizable states considered in [3]. In Section 4, as a first application of the above results, we prove that the attenuation (beam splitting) process for optical communication treated in [21] can be described in a simpler and more general way in terms of liftings and of transition expectations. The error probabilty of information transmission in the attenuation process is rederived from our new description. We also obtain some new results concerning the explicit computation of error probabilities in the squeezing case.

Accardi, L. [Dipartimento di Matematica, Centro Matematico V. Volterra, Universita di Roma II, Rome (Italy); Ohya, M. [Department of Information Sciences, Science University of Tokyo, Noda City, Chiba 278 (Japan)

1999-01-15

409

Couvade Syndrome among Polish expectant fathers  

PubMed Central

Background The aim of the conducted study was to analyze the phenomenon of Couvade Syndrome amongst fathers expecting their children in Poland. The authors examined the frequency of couvade symptoms in male subjects as well as their associations with male empathy. Material/Methods The research involved 143 expectant fathers. All subjects attended antenatal classes, and their female partners were in their third trimester. Before the start of classes, participants were asked to fill in the following questionnaires: a survey for measurement of Couvade Syndrome (which includes a set of 16 symptoms identified by Lipkin and Lamb (19) and translated into Polish), and the Empathic Sensitiveness Scale (SWE). Although participants, on average, did not experience Couvade Syndrome, they did experience symptoms that are commonly linked with the syndrome, namely those related to weight (weight gain, changes in appetite and flatulence). Results The results indicate that expectant fathers experience couvade symptoms related to weight (weight gain, changes in appetite and flatulence). The only empathic component that positively correlates with Couvade Syndrome is personal distress, i.e. the tendency to take on the negative emotions of others. Demographic characteristics are not associated with Couvade Syndrome. Conclusions The frequency of couvade symptoms in male subjects is associated with male empathy. In other words, men who are emotionally sensitive or prone to distress may physiologically experience the pregnancy of their female partners, which can be interpreted as compathy.

Kazmierczak, Maria; Kielbratowska, Bogumila; Pastwa-Wojciechowska, Beata; Preis, Krzysztof

2013-01-01

410

Setting clear expectations for safety basis development  

SciTech Connect

DOE-RL has set clear expectations for a cost-effective approach for achieving compliance with the Nuclear Safety Management requirements (10 CFR 830, Nuclear Safety Rule) which will ensure long-term benefit to Hanford. To facilitate implementation of these expectations, tools were developed to streamline and standardize safety analysis and safety document development resulting in a shorter and more predictable DOE approval cycle. A Hanford Safety Analysis and Risk Assessment Handbook (SARAH) was issued to standardized methodologies for development of safety analyses. A Microsoft Excel spreadsheet (RADIDOSE) was issued for the evaluation of radiological consequences for accident scenarios often postulated for Hanford. A standard Site Documented Safety Analysis (DSA) detailing the safety management programs was issued for use as a means of compliance with a majority of 3009 Standard chapters. An in-process review was developed between DOE and the Contractor to facilitate DOE approval and provide early course correction. As a result of setting expectations and providing safety analysis tools, the four Hanford Site waste management nuclear facilities were able to integrate into one Master Waste Management Documented Safety Analysis (WM-DSA).

MORENO, M.R.

2003-05-03

411

Suprathreshold stochastic resonance and maximizing network for watermark detection  

NASA Astrophysics Data System (ADS)

We propose a novel method that improves watermark detection performance, based on suprathreshold stochastic resonance (SSR) with a maximizing network. The detection performance is measured in terms of correlation. The proposed method has been tested on different gray-scale images, and we found that an original image is not required for watermark detection, so this method is blind. We improved the correlation between an original watermark and the SSR with maximizing network-based discrete wavelet transform coefficients of the watermarked image. Our experimental results have been compared with the different existing techniques and were found superior in terms of correlation and ratio of correlation to threshold.

Jha, Rajib Kumar; Biswas, Prabir Kumar; Gupta, Bhupendra; Mishra, Deepak

2012-01-01

412

Stability region maximization by decomposition-aggregation method. [Skylab stability  

NASA Technical Reports Server (NTRS)

This work is to improve the estimates of the stability regions by formulating and resolving a proper maximization problem. The solution of the problem provides the best estimate of the maximal value of the structural parameter and at the same time yields the optimum comparison system, which can be used to determine the degree of stability of the Skylab. The analysis procedure is completely computerized, resulting in a flexible and powerful tool for stability considerations of large-scale linear as well as nonlinear systems.

Siljak, D. D.; Cuk, S. M.

1974-01-01

413

Chest wall deformity following maximal tissue expansion for breast reconstruction.  

PubMed

Forty-three women, in a series of 150, participated in a prospective study that examined their chest walls for deformities 3 months after maximal tissue expansion for single-breast reconstruction. Computed tomography imaging was used for this purpose. Twenty-one patients underwent immediate breast reconstruction and the other 22 patients underwent delayed reconstruction. Fifty-three percent had some chest wall abnormality. In the delayed group, chest wall deformities were more statistically significant (p < 0.001). Our findings suggest that chest wall deformity is a common occurrence after maximal tissue expansion for breast reconstruction. PMID:8919374

Moor, E V; Wexler, M R; Bar-Ziv, Y; Weinberg, A; Chaouat, M; Ad-El, D; Raveh, T; Alfie, M; Caspi, R; Neuman, A

1996-02-01

414

Projection of two biphoton qutrits onto a maximally entangled state.  

PubMed

Bell state measurements, in which two quantum bits are projected onto a maximally entangled state, are an essential component of quantum information science. We propose and experimentally demonstrate the projection of two quantum systems with three states (qutrits) onto a generalized maximally entangled state. Each qutrit is represented by the polarization of a pair of indistinguishable photons-a biphoton. The projection is a joint measurement on both biphotons using standard linear optics elements. This demonstration enables the realization of quantum information protocols with qutrits, such as teleportation and entanglement swapping. PMID:21517363

Halevy, A; Megidish, E; Shacham, T; Dovrat, L; Eisenberg, H S

2011-04-01

415

Maximization of thermal entanglement of arbitrarily interacting two qubits  

SciTech Connect

We investigate the thermal entanglement of interacting two qubits. We maximize it by tuning a local Hamiltonian under a given interaction Hamiltonian. We prove that the optimizing local Hamiltonian takes a simple form which does not depend on the temperature and that the corresponding optimized thermal entanglement decays as 1/(TlnT) at high temperatures. We also find that at low temperatures the thermal entanglement is maximum without any local Hamiltonians and that the second derivative of the maximized thermal entanglement changes discontinuously at the boundary between the high- and low-temperature phases.

Kuwahara, Tomotaka [Department of Physics, University of Tokyo, Komaba, Meguro, Tokyo 153-8505 (Japan); Hatano, Naomichi [Institute of Industrial Science, University of Tokyo, Komaba, Meguro, Tokyo 153-8505 (Japan)

2011-06-15

416

[Utilities: a solution of a decision problem?].  

PubMed

Utility is a concept that originates from utilitarianism, a highly influential philosophical school in the Anglo-American world. The cornerstone of utilitarianism is the principle of maximum happiness or utility. In the medical sciences, this utility approach has been adopted and developed within the field of medical decision making. On an operational level, utility is the evaluation of a health state or an outcome on a one-dimensional scale ranging from 0 (death) to 1 (perfect health). By adding the concept of expectancy, the graphic representation of both concepts in a decision tree results in the specification of expected utilities and helps to resolve complex medical decision problems. Criticism of the utility approach relates to the rational perspective on humans (which is rejected by a considerable fraction of research in psychology) and to the artificial methods used in the evaluation of utility, such as Standard Gamble or Time Trade Off. These may well be the reason why the utility approach has never been accepted in Germany. Nevertheless, innovative concepts for defining goals in health care are urgently required, as the current debate in Germany on "Nutzen" (interestingly translated as 'benefit' instead of as 'utility') and integrated outcome models indicates. It remains to be seen whether this discussion will lead to a re-evaluation of the utility approach. PMID:19216241

Koller, Michael; Ohmann, Christian; Lorenz, Wilfried

2008-01-01

417

A switching fabric performance evaluation model based on double-indicator utility function  

Microsoft Academic Search

Utility function theory in microeconomics is introduced into the switching fabric performance evaluation in this paper. We propose a new switch performance evaluation model-based on delay utility function, and with utility maximization theory to find out the optimum allocation scheme of network resources. And then we extend the model, integrate the two most closely to the nature of traffic flow

Li Xiuqin; Zhao Xiuxiu; Lan Julong; Yang Xiliang

2010-01-01

418

Mentoring as Professional Development for Novice Entrepreneurs: Maximizing the Learning  

ERIC Educational Resources Information Center

Mentoring can be seen as relevant if not essential in the continuing professional development of entrepreneurs. In the present study, we seek to understand how to maximize the learning that occurs through the mentoring process. To achieve this, we consider various elements that the literature suggested are associated with successful mentoring and…

St-Jean, Etienne

2012-01-01

419

Adapting Grice's Maxims in the Teaching of Writing.  

ERIC Educational Resources Information Center

Grice's maxims, which define the conditions for efficient spoken communications, can be adapted to the teaching of writing by providing both teachers and writers with a way of understanding successful and unsuccessful written correspondence in mono- and cross-cultural settings. Cultural differences are revealed in a survey of lay readers'…

White, Ron

2001-01-01

420

Mutual information maximizing linear precoding for parallel layer MIMO detection  

Microsoft Academic Search

In this paper mutual information maximizing linear precoding for MIMO transmission using finite signal alphabets and a parallel layer MIMO detection scheme is derived. The derivation exploits that the mutual information of the parallel detection scheme can be expressed in terms of the mutual information associated with optimal maximum likelihood de- tection. Results show that the large performance gap between

Eckhard Ohlmer; Udo Wachsmann; Gerhard Fettweis

2011-01-01

421

On distributed maximization of algebraic connectivity in robotic networks  

Microsoft Academic Search

We consider the problem of maximizing the alge- braic connectivity of the communication graph in a network of mobile robots by moving them into appropriate positions. We describe the Laplacian of the graph as dependent on the pairwise distance between the robots and formulate an approx- imate problem as a Semi-Definite Program (SDP). We propose a consistent, non-iterative distributed solution

Andrea Simonetto; Tamas Keviczky; Robert Babuska

2011-01-01

422

How to Maximize Learning for Gifted Math Students  

ERIC Educational Resources Information Center

Having a gifted math or science student in the family or classroom is a fascination as well as a significant challenge and responsibility for many parents and teachers. In order to help maximize student learning, several questions need to be asked. What should be the role of technology? How well do traditional schools serve gifted students? What…

Chamberlin, Scott A.

2008-01-01

423

Amino Acid Diets and Maximal Growth in the Rat  

Microsoft Academic Search

Amino acid diets fed in an agar gel have been found to support weight gains of rats as great or greater than those obtained with diets containing an equiva lent quantity of casein supplemented with methionine. Over 1% arginine, 0.6% asparagine and feeding the diet in gel form were necessary to obtain maximal weight gain. The diet contained amino acids

Q. R. ROGERS ANDA; E. HARPER

424

Abelian loops and electric flux in maximal Abelian gauges.  

National Technical Information Service (NTIS)

In order to further test't Hooft's confinement mechanism, we have carried out Monte Carlo calculations of 'abelian' Wilson loops, and the color distribution of electric flux, in certain maximal abelian gauges of SU(2) lattice gauge theory. The electric fl...

J. Greensite J. Iwasaki

1990-01-01

425

Maximally permissive supervisor of marine canal traffic system  

Microsoft Academic Search

This paper deals with the automatic traffic control of vessels moving through the marine canal traffic system. Dangerous vessel deadlock situations may occur in case of vessels' irregular moving through the system. To avoid this, the vessel traffic is supervised and controlled by traffic lights. Derived supervisor is maximally permissive (responsible for vessels' stopping only in the case of dangerous

D. Kezic; I. Vujovic; I. Kuzmanic

2006-01-01

426

Nursing Students' Awareness and Intentional Maximization of Their Learning Styles  

ERIC Educational Resources Information Center

This small, descriptive, pilot study addressed survey data from four levels of nursing students who had been taught to maximize their learning styles in a first-semester freshman success skills course. Bandura's Agency Theory supports the design. The hypothesis was that without reinforcing instruction, the students' recall and application of that…

Mayfield, Linda Riggs

2012-01-01

427

MAXIMIZING THREE-PHASE DIRECT-CONTACT HEAT EXCHANGER OUTPUT  

Microsoft Academic Search

Findings that maximize output performance of three-phase spray columns show that dramatic increases in total heat transfer can be achieved. Results from simulations are presented that show when the dispersed fluid is introduced into the exchanger at or near its saturation temperature, increases of approximately a half order of magnitude are possible. In some cases, reversals in previously reported trends

Richard A. Brickman; Robert F. Boehm

1994-01-01

428

Apportioning Program Evaluation Resources to Maximize Information Yield.  

ERIC Educational Resources Information Center

Not all data for a program evaluation may be equally valuable, and costs of collection may vary when using several methods to obtain data from several sources. An approach to maximize information yield for a fixed, limited budget using a mathematical technique known as linear programming is described and generalized. (Author/CM)

Sadler, D. Royce

1982-01-01

429

Entanglement concentration for non-maximally entangled states of qudits  

Microsoft Academic Search

Entanglement concentration for higher dimensional quantum systems, qudits, is studied. In particular, we study a concentration protocol based on entanglement swapping of non-maximally entangled qudits via quantum state discrimination. We compare this protocol to a concentration scheme based on copies of the state to be concentrated, local transformations and two-way communications. We show that the success probability of the first

M. Yang; A. Delgado; L. Roa; C. Saavedra

2009-01-01

430

PROFIT-MAXIMIZING PRINCIPLES, INSTRUCTIONAL UNITS FOR VOCATIONAL AGRICULTURE.  

ERIC Educational Resources Information Center

THE PURPOSE OF THIS GUIDE IS TO ASSIST VOCATIONAL AGRICULTURE TEACHERS IN STIMULATING JUNIOR AND SENIOR HIGH SCHOOL STUDENT THINKING, UNDERSTANDING, AND DECISION MAKING AS ASSOCIATED WITH PROFIT-MAXIMIZING PRINCIPLES OF FARM OPERATION FOR USE IN FARM MANAGEMENT. IT WAS DEVELOPED UNDER A U.S. OFFICE OF EDUCATION GRANT BY TEACHER-EDUCATORS, A FARM…

BARKER, RICHARD L.

431

Ungulate foraging strategies: energy maximizing or time minimizing?  

Microsoft Academic Search

Summary 1. Many classical models of ungulate foraging are premised on energy maximization, yet limited empirical evidence and untested currency assumptions make the choice of currency a non-trivial issue. The primary constraints on forage intake of ungulates are forage quality and availability. Using a model that incorporates these two constraints, we predicted the optimal biomass of forage patches for ungulate

Carita M. Bergman; John M. Fryxell; C. Cormack Gates; Daniel Fortin

2001-01-01

432

Animal Guts as Ideal Chemical Reactors: Maximizing Absorption Rates  

Microsoft Academic Search

I solved equations that describe coupled hydrolysis in and absorption from a continuously stirred tank reactor (CSTR), a plug flow reactor (PFR), and a batch reactor (BR) for the rate of ingestion and\\/or the throughput time that maximizes the rate of absorption (=gross rate of gain from digestion). Predictions are that foods requiring a single hydrolytic step (e.g., disaccharides) yield

Peter A. Jumars

2000-01-01

433

Integrated system to maximize efficiency in transit maintenance departments  

Microsoft Academic Search

Purpose – The purpose of this research is to show how an integrated system serves as an information support tool to assists maintenance managers to analyze data and evaluate alternatives in order to make better decisions that maximize efficiency in transit operations. Design\\/methodology\\/approach – A system which consists of a mathematical scheduling model that interacts with a forecasting model and

Paula Lopez; Grisselle Centeno

2006-01-01

434

Maximally entangled mixed-state generation via local operations  

SciTech Connect

We present a general theoretical method to generate maximally entangled mixed states of a pair of photons initially prepared in the singlet polarization state. This method requires only local operations upon a single photon of the pair and exploits spatial degrees of freedom to induce decoherence. We report also experimental confirmation of these theoretical results.

Aiello, A.; Puentes, G.; Voigt, D.; Woerdman, J. P. [Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden (Netherlands)

2007-06-15

435

Counterexamples to the maximality conjecture of Landau-Higgs models  

NASA Astrophysics Data System (ADS)

Two counterexamples to the Ascher-Michel maximality conjecture are presented. One of the models is extended to the case of reducible order parameter/Higgs field to provide a counterexample to the Gell-Mann-Slansky conjecture. Physical consequences of these counterexamples are discussed in the context of phase transitions.

Jari?, Marko V.

436

Maximal neutrino mixing from an attractive infrared fixed point  

Microsoft Academic Search

In the Standard Model (and MSSM), renormalization effects on neutrino mixing are generally very small and the attractive fixed points are at vanishing neutrino mixing. However for multi-Higgs extensions of the Standard Model, renormalization effects on neutrino mixing can be large and nontrivial fixed points are possible. Here we examine a simple two-Higgs model. For two flavors, maximal mixing is

James Pantaleone; T. K. Kuo; Guo-Hong Wu

2001-01-01

437

Extreme video retrieval: joint maximization of human and computer performance  

Microsoft Academic Search

We present an efficient system for video search that maximizes the use of human bandwidth, while at the same time exploiting the machine's ability to learn in real-time from user selected relevant video clips. The system exploits the human capability for rapidly scanning imagery augmenting it with an active learning loop, which attempts to always present the most relevant material

Alexander G. Hauptmann; Wei-hao Lin; Rong Yan; Jun Yang; Ming-yu Chen

2006-01-01

438

Maximally Permissive Hierarchical Control of Decentralized Discrete Event Systems  

Microsoft Academic Search

The subject of this paper is the synthesis of natural projections that serve as nonblocking and maximally permissive ab- stractions for the hierarchical and decentralized control of large- scale discrete event systems. To this end, existing concepts for non- blocking abstractions such as natural observers and marked string accepting (msa)-observers are extended by local control consistency (LCC) as a novel

Klaus Schmidt; Christian Breindl

2011-01-01

439

Influence of Heat Stress and Acclimation on Maximal Aerobic Power.  

National Technical Information Service (NTIS)

Thirteen male volunteers performed cycle ergometer maximal oxygen uptake (V02 max) tests in moderate (21 C, 30% rh) and hot (49 C, 20% rh) environments, before and after a nine-day heat acclimation program. This program resulted in significantly decreased...

M. N. Sawka A. J. Young B. C. Cadarette L. Levine K. B. Pandolf

1984-01-01

440

Maximal Power Outputs during the Wingate Anaerobic Test.  

National Technical Information Service (NTIS)

The purpose of this study was to determine the resistance settings which elicit maximal values of power output (PO) values during performance of the Wingate Test (WT). Nineteen male subjects performed multiple WT in a random order at resistance settings r...

J. F. Patton M. M. Murphy F. A. Frederick

1984-01-01

441

Influence of Heat Stress an Acclimation on Maximal Aerobic Power.  

National Technical Information Service (NTIS)

Thirteen male volunteers performed cycle ergometer maximal oxygen uptake (VO2 max) tests in moderate (21 C, 30% rh) and hot (49C, 20% rh) environments, before and after a nine-day heat acclimation program. This program resulted in significantly decreased ...

M. N. Sawka A. J. Young B. C. Cadarette L. Levine K. B. Pandolf

1985-01-01

442

On Maximal Subalgebras and the Hypercentre of Lie Algebras.  

ERIC Educational Resources Information Center

Derives two sufficient conditions for a finitely generated Lie algebra to have the nilpotent hypercenter. Presents a relatively large class of generalized soluble Lie algebras. Proves that if a finitely generated Lie algebra has a nilpotent maximal subalgebra, the Fitting radical is nilpotent. (DDR)

Honda, Masanobu

1997-01-01

443

Optimal reconfiguration of radial distribution systems to maximize loadability  

Microsoft Academic Search

This paper presents a new method for optimal reconfiguration of radial distribution systems (RDS). Optimal reconfiguration involves selection of the best set of branches to be opened, one each from each loop, such that the resulting RDS has the desired performance. Amongst the several performance criteria considered for optimal network reconfiguration, maximizing loadability is an important one. Owing to the

B. Venkatesh; Rakesh Ranjan; H. B. Gooi

2004-01-01

444

CINR difference analysis of optimal combining versus maximal ratio combining  

Microsoft Academic Search

The statistical gain differences between two common spatial combining algorithms: optimum combining (OC) and maximal ratio combining (MRC) are analyzed using a gain ratio method. Using the receive carrier-to-interference plus noise ratio (CINR), the gain ratio CINR CINR is evaluated in a flat Rayeligh fading communications system with multiple interferers. Exact analytical solutions are derived for the probability density function

Joe P. Burke; James R. Zeidler; B. D. Rao

2005-01-01

445

On Adaptation, Maximization, and Reinforcement Learning among Cognitive Strategies  

ERIC Educational Resources Information Center

Analysis of binary choice behavior in iterated tasks with immediate feedback reveals robust deviations from maximization that can be described as indications of 3 effects: (a) a payoff variability effect, in which high payoff variability seems to move choice behavior toward random choice; (b) underweighting of rare events, in which alternatives…

Erev, Ido; Barron, Greg

2005-01-01

446

A Linear Algorithm for the Maximal Planar Subgraph Problem  

Microsoft Academic Search

We construct an optimal linear algorithm for the maximal planar subgraph problem: given a graph G, find a planar subgraph G of G such that adding to G any edge of G not present in G leads to a nonplanar graph. Our solution is based on a dynamic graph search procedure and a fast data structure for on-line planarity testing

Hristo Djidjev

1995-01-01

447

Maximal covering with network survivability requirements in wireless mesh networks  

Microsoft Academic Search

This paper introduces an approach for survivable network design of citywide wireless broadband. Our primary interest is in methodology for ensuring maximal coverage and reliable provision of services based on network connectivity. From a public perspective, ubiquitous and reliable provision of broadband services is important. Thus our approach will be particularly relevant to decision makers in local municipalities who are

Gunhak Lee; Alan T. Murray

2010-01-01

448

Maximality and Idealized Cognitive Models: The Complementation of Spanish "Tener."  

ERIC Educational Resources Information Center

Discusses the bare-noun phrase (NP) complementation pattern of the Spanish verb "tener" (have). Shows that the maximality of the complement NP is dependent upon three factors: (1) idiosyncratic valence requirements; (2) encyclopedic knowledge related to possession; and (3) contextualized semantic construal. (Author/VWL)

Hilferty, Joseph; Valenzuela, Javier

2001-01-01

449

Feature Selection for Maximizing the Area Under the ROC Curve  

Microsoft Academic Search

Feature selection is an important pre-processing step for solving classification problems. A good feature selection method may not only improve the performance of the final classifier, but also reduce the computational complexity of it. Traditionally, feature selection methods were developed to maximize the classification accuracy of a classifier. Recently, both theoretical and experimental studies revealed that a classifier with the

Rui Wang; Ke Tang

2009-01-01

450

The maximal VHDL subset with a cycle-level abstraction  

Microsoft Academic Search

The maximal VHDL subset with a cycle-level abstraction is defined. This subset requires that the description have three semantic properties: responsiveness, modularity and causal- ity, but full VHDL is neither modular nor causal. Synchro- nous VHDL is the responsive, modular and causal subset of VHDL. The compiler uses modularity-checking and causal- ity-checking to identify admissible programs.

Wendell C. Baker; A. Richard Newton

1996-01-01

451

Throughput Guarantees Through Maximal Scheduling in Wireless Networks  

Microsoft Academic Search

We address the question of providing throughput guarantees through distributed scheduling, which has remained an open problem for some time. We consider a simple distributed scheduling strategy, maximal scheduling, and prove that it attains a guaranteed fraction of the maximum throughput region in arbitrary wireless networks. The guaranteed fraction depends on \\

Prasanna Chaporkar; Koushik Kar; Saswati Sarkar

2005-01-01

452

The climate is not what you expect  

NASA Astrophysics Data System (ADS)

Prevailing definitions of climate are not much different from "the climate is what you expect, the weather is what you get". Using a variety of sources including reanalyses and paleo data, and aided by notions and analysis techniques from Nonlinear Geophysics, we argue that this dictum is fundamentally wrong. In addition to the weather and climate, there is a qualitatively distinct intermediate regime extending over a factor of ? 1000 in scale. For example, mean temperature fluctuations increase up to about 5 K at 10 days (the lifetime of planetary structures), then decrease to about 0.2 K at 30 years, and then increase again to about 5 K at glacial-interglacial scales. Both deterministic GCM's with fixed forcings ("control runs") and stochastic turbulence-based models reproduce the first two regimes, but not the third. The middle regime is thus a kind of low frequency "macroweather" not "high frequency climate". Regimes whose fluctuations increase with scale appear unstable whereas regimes where they decrease appear stable. If we average macroweather states over periods ? 30 years, the results thus have low variability. In this sense, macroweather is what you expect. We can use the critical duration of ? 30 years to define (fluctuating) "climate states". As we move to even lower frequencies, these states increasingly fluctuate - appearing unstable so that the climate is not what you expect. The same methodology allows us to categorize climate forcings according to whether their fluctuations decrease or increase with scale and this has important implications for GCM's and for climate change and climate predictions.

Varon, D.; Lovejoy, S.; Schertzer, D. J.

2012-12-01

453

Comparison of myocardial /sup 201/Tl clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication  

SciTech Connect

Recently the quantitation of regional /sup 201/Tl clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although /sup 201/Tl clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial /sup 201/Tl activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean /sup 201/Tl clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those who do not exercise to an accepted end point.

Massie, B.M.; Wisneski, J.; Kramer, B.; Hollenberg, M.; Gertz, E.; Stern, D.

1982-05-01

454

Contributions of leaf photosynthetic capacity, leaf angle and self-shading to the maximization of net photosynthesis in Acer saccharum: a modelling assessment  

PubMed Central

Background and Aims Plants are expected to maximize their net photosynthetic gains and efficiently use available resources, but the fundamental principles governing trade-offs in suites of traits related to resource-use optimization remain uncertain. This study investigated whether Acer saccharum (sugar maple) saplings could maximize their net photosynthetic gains through a combination of crown structure and foliar characteristics that let all leaves maximize their photosynthetic light-use efficiency (?). Methods A functional–structural model, LIGNUM, was used to simulate individuals of different leaf area index (LAIind) together with a genetic algorithm to find distributions of leaf angle (LA) and leaf photosynthetic capacity (Amax) that maximized net carbon gain at the whole-plant level. Saplings grown in either the open or in a forest gap were simulated with Amax either unconstrained or constrained to an upper value consistent with reported values for Amax in A. saccharum. Key Results It was found that total net photosynthetic gain was highest when whole-plant PPFD absorption and leaf ? were simultaneously maximized. Maximization of ? required simultaneous adjustments in LA and Amax along gradients of PPFD in the plants. When Amax was constrained to a maximum, plants growing in the open maximized their PPFD absorption but not ? because PPFD incident on leaves was higher than the PPFD at which ?max was attainable. Average leaf ? in constrained plants nonetheless improved with increasing LAIind because of an increase in self-shading. Conclusions It is concluded that there are selective pressures for plants to simultaneously maximize both PPFD absorption at the scale of the whole individual and ? at the scale of leaves, which requires a highly integrated response between LA, Amax and LAIind. The results also suggest that to maximize ? plants have evolved mechanisms that co-ordinate the LA and Amax of individual leaves with PPFD availability.

Posada, Juan M.; Sievanen, Risto; Messier, Christian; Perttunen, Jari; Nikinmaa, Eero; Lechowicz, Martin J.

2012-01-01

455

Design labs: Students' expectations and reality  

NASA Astrophysics Data System (ADS)

In a study reported in PERC 2004 the authors described how introductory physics labs in which students design their own experiments help them develop scientific abilities. These include the ability to design an experiment to solve a problem, to collect and analyze data and to communicate the details of the experimental procedure. The goal of the present study is to investigate the social aspect of student learning in these labs: whether students' expectations are consistent with the goals of the labs, whether student assessment of their learning in the labs matches the goals, and whether students perceive the labs as helpful in learning useful skills.

Etkina, Eugenia; Murthy, Sahana

2006-02-01

456

Design labs: Students' expectations and reality  

NSDL National Science Digital Library

In a study reported in PERC 2004 the authors described how introductory physics labs in which students design their own experiments help them develop scientific abilities. These include the ability to design an experiment to solve a problem, to collect and analyze data and to communicate the details of the experimental procedure. The goal of the present study is to investigate the social aspect of student learning in these labs: whether students' expectations are consistent with the goals of the labs, whether student assessment of their learning in the labs matches the goals, and whether students perceive the labs as helpful in learning useful skills.

Etkina, Eugenia; Murthy, Sahana

2009-07-13

457

Flood frequency; expected and unexpected probabilities  

USGS Publications Warehouse

Flood-frequency curves may be defined either with or without an ' expeced probability ' adustment; and the two curves differ in the way that they attempt to average the time-sampling uncertainties. A curve with no adustment is shown to estimate a median value of both discharge and frequency of occurrence, while an expected probability curve is shown to estimate a mean frequency of flood years. The attributes and constraints of the two types of curves for various uses are discussed. (Woodard-USGS)

Thomas, D. M.

1976-01-01

458

Distributed computing environment monitoring and user expectations  

SciTech Connect

This paper discusses the growing needs for distributed system monitoring and compares it to current practices. It then goes on to identify the components of distributed system monitoring and shows how they are implemented and successfully used at one site today to address the Local Area Network (LAN), network services and applications, the Wide Area Network (WAN), and host monitoring. It shows how this monitoring can be used to develop realistic service level expectations and also identifies the costs. Finally, the paper briefly discusses the future challenges in network monitoring.

Cottrell, R.L.A.; Logg, C.A.

1995-11-01

459

The Overseas Doctors Training Scheme: failing expectations.  

PubMed Central

The Overseas Doctors Training Scheme needs appraisal. Set up 10 years ago to improve the quality of postgraduate training that overseas (non-European) doctors receive in Britain, the scheme has been popular, but it is questionable how far it has achieved its aims. If Britain is to continue to employ large numbers of overseas doctors in training grades, both through the scheme and through independent arrangements, the apparent mismatch between their expectations and the reality of what Britain offers must be tackled. Images p1629-a

Richards, T.

1994-01-01

460

Diverse expected gradient active learning for relative attributes.  

PubMed

The use of relative attributes for semantic understanding of images and videos is a promising way to improve communication between humans and machines. However, it is extremely labor- and time-consuming to define multiple attributes for each instance in large amount of data. One option is to incorporate active learning, so that the informative samples can be actively discovered and then labeled. However, most existing active-learning methods select samples one at a time (serial mode), and may therefore lose efficiency when learning multiple attributes. In this paper, we propose a batch-mode active-learning method, called diverse expected gradient active learning. This method integrates an informativeness analysis and a diversity analysis to form a diverse batch of queries. Specifically, the informativeness analysis employs the expected pairwise gradient length as a measure of informativeness, while the diversity analysis forces a constraint on the proposed diverse gradient angle. Since simultaneous optimization of these two parts is intractable, we utilize a two-step procedure to obtain the diverse batch of queries. A heuristic method is also introduced to suppress imbalanced multiclass distributions. Empirical evaluations of three different databases demonstrate the effectiveness and efficiency of the proposed approach. PMID:24983113

You, Xinge; Wang, Ruxin; Tao, Dacheng

2014-07-01

461

Neuromuscular fatigue after maximal exercise in patients with cystic fibrosis.  

PubMed

The aim of this study was to determine whether patients with cystic fibrosis (CF), despite their ventilatory limitation, would develop neuromuscular fatigue of quadriceps muscles following a maximal cycling exercise. Eleven adults with CF (age=26.8±6.9years; forced expiratory volume in 1s=54.1±12.8% predicted) and 11 age-matched healthy subjects performed a maximal incremental cycle test with respiratory gas exchange measurements. Maximal voluntary contraction (MVC) and electromyographic (EMG) activity of the vastus medialis muscle were recorded before and after exercise. Neural and contractile properties of the quadriceps were also investigated using femoral nerve electrical stimulation. Patients had lower exercise capacity, peak oxygen uptake and MVC than controls. MVC fell significantly postexercise in both groups (CF: -20±10%, controls: -19±6%; p<0.01). EMG root mean square values, M-wave amplitude and duration were unchanged in both groups. Peak twitch (-46.9±13.8%), maximal rate of twitch torque development (-50.3±13.8%) and relaxation (-35.2±19.5%) were all reduced after exercise in CF patients. The control group followed the same pattern (-38.4±14.4%, -42.1±14.7% and -15±20.4%) but the statistical significance was not reached for the maximal rate of twitch torque relaxation. In conclusion, CF patients demonstrated lower limb fatigue following symptom-limited cycle exercise, which was comparable to that exhibited by healthy controls. This fatigue may be due to contractile impairments and not to transmission failure. Further studies should be conducted in a larger sample to confirm these preliminary results. PMID:21078561

Vallier, J M; Gruet, M; Mely, L; Pensini, M; Brisswalter, J

2011-04-01

462

When feeling bad is expected to be good: emotion regulation and outcome expectancies in social conflicts.  

PubMed

According to the instrumental approach to emotion regulation, people may want to experience even unpleasant emotions to attain instrumental benefits. Building on value-expectancy models of self-regulation, we tested whether people want to feel bad in certain contexts specifically because they expect such feelings to be useful to them. In two studies, participants were more likely to try to increase their anger before a negotiation when motivated to confront (vs. collaborate with) a negotiation partner. Participants motivated to confront (vs. collaborate with) their partner expected anger to be more useful to them, and this expectation in turn, led them to try to increase their anger before negotiating. The subsequent experience of anger, following random assignment to emotion inductions (Study 1) or engagement in self-selected emotion regulation activities (Study 2), led participants to be more successful at getting others to concede to their demands, demonstrating that emotional preferences have important pragmatic implications. PMID:21728413

Tamir, Maya; Ford, Brett Q

2012-08-01

463

[Life expectancy as an indicator of outcome].  

PubMed

Usually survival studies evaluate the percentage of subjects alive or disease-free at a given point in time (cumulative survival percentage). These studies require a lengthy period both for follow up and for the collection of an exhaustive number of cases. In addition, for cancer types with a sharp gradient of cumulative mortality, the estimate may be unstable. On the database of children with Acute Lymphoblastic Leukaemia (ALL) collected by the Childhood Cancer Registry of Piedmont (CCRP) in 1979-1991, we have estimated an alternative time-dimensional index to estimate both patients' life expectancy of patient and number of years gained to death. These estimates have been compared in subsets of the database corresponding to different periods of diagnosis and efficacy of treatment. Life expectancy has been evaluated as the area under the survival curve, on the assumption that after a number of years since diagnosis, survivors have the same mortality rates of the general population. Clinicians are invited to take into consideration the approach described in the present note. PMID:15532875

Viscomi, Silvia; Pastore, Guido; Dama, Elisa; Merletti, Franco; Magnani, Corrado

2004-01-01

464

Expectations and Interpretations During Causal Learning  

PubMed Central

In existing models of causal induction, 4 types of covariation information (i.e., presence/absence of an event followed by presence/absence of another event) always exert identical influences on causal strength judgments (e.g., joint presence of events always suggests a generative causal relationship). In contrast, we suggest that, due to expectations developed during causal learning, learners give varied interpretations to covariation information as it is encountered and that these interpretations influence the resulting causal beliefs. In Experiments 1A–1C, participants’ interpretations of observations during a causal learning task were dynamic, expectation based, and, furthermore, strongly tied to subsequent causal judgments. Experiment 2 demonstrated that adding trials of joint absence or joint presence of events, whose roles have been traditionally interpreted as increasing causal strengths, could result in decreased overall causal judgments and that adding trials where one event occurs in the absence of another, whose roles have been traditionally interpreted as decreasing causal strengths, could result in increased overall causal judgments. We discuss implications for traditional models of causal learning and how a more top-down approach (e.g., Bayesian) would be more compatible with the current findings.

Luhmann, Christian C.; Ahn, Woo-kyoung

2012-01-01

465

Matlab Code for Solving Linear Rational Expectation Models with Lagged Expectations Quickly and Easily  

Microsoft Academic Search

This program contains a solution and an estimation method for linear rational expectations models with lagged expectations (e.g., sticky information). The solution method is a synthetic approach, combining state-space and infinite-MA representations with a simple system of linear equations. The advantage of the approach lies in its particular combination of methods familiar elsewhere in the literature to provide faster execution,

Alexander Meyer-Gohde

2007-01-01

466

Attenuated maximal muscle strength and peak power in children with sickle cell disease.  

PubMed

Dominant hand maximal handgrip strength evaluated with a handgrip dynamometer and peak power evaluated with a force plate, adjusted for body size and composition, were compared in African-American children aged 5 to 13 years, with and without type SS sickle cell disease (SCD-SS). Children with SCD-SS (n = 35; age, 9.0 ± 2.0 y) compared with healthy control children (n = 103; age, 8.6 ± 1.8 y) did not differ by age, sex, or pubertal status, yet had significantly lower Z scores for height, weight, body mass index, upper arm muscle area, upper arm fat area, fat mass-for-height and lean mass-for-height. Children with SCD-SS had significantly lower handgrip strength (12.7 ± 3.3 vs. 15.2 ± 5.1 kg, P < 0.008), peak power (882 ± 298 vs. 1167 ± 384 W, P < 0.001), and growth and body composition adjusted Z scores for handgrip strength (0.6 ± 1.3 standard deviations, P < 0.004) and peak power (male children = 1.0 ± 0.8 standard deviations, P < 0.0002; female children = 1.0 ± 1.7 standard deviations, P < 0.006). Maximal muscle strength and peak power are attenuated in children with SCD-SS compared with healthy control children beyond expectation for growth and body composition deficits suggesting that additional factors contribute to attenuation in anaerobic performance. PMID:21228717

Dougherty, Kelly A; Schall, Joan I; Rovner, Alisha J; Stallings, Virginia A; Zemel, Babette S

2011-03-01

467

Variability and typical error in the kinematics and kinetics of the maximal instep kick in soccer.  

PubMed

The purpose of this paper was to establish the variability and typical error of kinematic and kinetic variables representing the maximal instep kick in soccer for both the kicking and support legs. Ten skilled (good amateur or semi-professional) soccer players performed 20 maximal instep kicks of a stationary ball into a goal mouth. Motion of the kicking and support legs was recorded by an optoelectronic motion analysis system, and a six degrees of freedom model was used to compute kinematic and kinetic variables. Participants repeated the kicks on a second day at least 1 week later. The mean within-subject coefficient of variation across the kinematic and kinetic variables, trials, and days was 16% and did not change substantially as trial number increased or between day of test. Increasing trial number reduced the typical error (as determined by the standard error of the mean) such that for 20 trials 75% of the variables were below an arbitrary 5% threshold. It was concluded that for kicking investigations, 10-15 trials could be used and typical errors of 5% should be expected. PMID:24245053

Lees, Adrian; Rahnama, Nader

2013-09-01

468

Trade-offs between burst performance and maximal exertion capacity in a wild amphibian, Xenopus tropicalis.  

PubMed

Trade-offs are thought to impose barriers to phenotypic diversification and may limit the evolutionary responses of organisms to environmental changes. In particular, locomotor trade-offs between endurance or maximal exertion capacity and burst performance capacity have been observed in some species and may constrain the ability of organisms to disperse. Here, we tested for the presence of locomotor trade-offs between maximal exertion and burst performance capacity in an aquatic frog, the tropical clawed frog (Xenopus tropicalis). Given the importance of overland dispersal for this species, we focused on terrestrial exertion capacity (time and distance jumped until exhaustion) and tested whether it trades-off with aquatic burst performance capacity (maximum instantaneous velocity and acceleration), which is likely to be relevant in the context of predator escape and prey capture. Our data show that in both sexes, individuals with longer hindlimbs display higher endurance. Additionally, in females forelimb length was positively correlated with aquatic burst performance capacity and negatively correlated with terrestrial exertion. Trade-offs between endurance and burst performance capacity were detected, but were significant in males only. Finally, males and females differ in morphology and performance. Our data suggest that trade-offs are not universal and may be driven by sex-dependent selection on locomotor capacity. Moreover, our results suggest that locomotor trade-offs may result in sex-biased dispersal under selection for improved endurance capacity as is expected under habitat fragmentation scenarios. PMID:22660787

Herrel, Anthony; Bonneaud, Camille

2012-09-01

469

Heavy Stable Isotopes: From Exceptional to Expected  

NASA Astrophysics Data System (ADS)

Less than a decade ago, the stable isotope geochemistry of transition metals and other "heavy" elements was a highly specialized niche confined to a few seemingly exceptional elements. This situation was transformed by the development and refinement of MC-ICP-MS techniques, particularly in the last five years. Measurable stable isotope variations turn out to be ubiquitous across the periodic table, from Li to Hg. It is now safe to assume that the isotopic composition of any element with two or more stable isotopes is measurably variable. What was once exceptional is now expected. Among the first of these new systems to be explored were Fe and Mo isotopes. A number of lessons emerging from this work can be applied to the development of other isotope systems. Most important is that initial expectations are often wrong. For example, based on their environmental chemistries it was expected that redox reactions should produce some of the largest isotope effects for both elements. In the case of Fe, theoretical and experimental studies converge to convincingly indicate that a fractionation of ~ 1.5 ‰/amu occurs between Fe(III) and Fe(II) aquo complexes at equilibrium (e.g., Welch et al., 2003; Anbar et al., 2005). Consistent with these findings, most natural variations of are < 1.5 ‰/amu (e.g., Johnson et al., 2004). This redox-related fractionation is at the heart of emerging interpretations of variations in the isotopic composition of Fe and their application to understanding ancient ocean redox (e.g., Dauphas et al., 2004; Rouxel et al., 2005). In contrast, Mo isotope variations turn out to be controlled only indirectly by redox conditions. Instead, one of the most important Mo isotope effects in the environment appears to be a fractionation of ~ 1 ‰/amu during adsorption of Mo to Mn-oxides (Barling et al., 2001; Siebert et al., 2003). This fractionation has been reproduced in the laboratory (Barling and Anbar, 2004) and appears to be an equilibrium isotope effect unrelated to Mo redox chemistry. Because the extent of Mn-oxide deposition on the seafloor is a function of ocean oxygenation, Mo isotopes are nevertheless emerging as a powerful ocean redox proxy (Arnold et al., 2004). Collectively, these and other findings demonstrate that MC-ICP-MS analyses open the door to rich new research areas, particularly when analyses of natural samples are combined with laboratory experiments and computational predictions to gain insight into fractionation mechanisms.

Anbar, A.

2006-12-01

470

Operation of MRO's High Resolution Imaging Science Experiment (HiRISE): Maximizing Science Participation  

NASA Technical Reports Server (NTRS)

Science return from the Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) will be optimized by maximizing science participation in the experiment. MRO is expected to arrive at Mars in March 2006, and the primary science phase begins near the end of 2006 after aerobraking (6 months) and a transition phase. The primary science phase lasts for almost 2 Earth years, followed by a 2-year relay phase in which science observations by MRO are expected to continue. We expect to acquire approx. 10,000 images with HiRISE over the course of MRO's two earth-year mission. HiRISE can acquire images with a ground sampling dimension of as little as 30 cm (from a typical altitude of 300 km), in up to 3 colors, and many targets will be re-imaged for stereo. With such high spatial resolution, the percent coverage of Mars will be very limited in spite of the relatively high data rate of MRO (approx. 10x greater than MGS or Odyssey). We expect to cover approx. 1% of Mars at approx. 1m/pixel or better, approx. 0.1% at full resolution, and approx. 0.05% in color or in stereo. Therefore, the placement of each HiRISE image must be carefully considered in order to maximize the scientific return from MRO. We believe that every observation should be the result of a mini research project based on pre-existing datasets. During operations, we will need a large database of carefully researched 'suggested' observations to select from. The HiRISE team is dedicated to involving the broad Mars community in creating this database, to the fullest degree that is both practical and legal. The philosophy of the team and the design of the ground data system are geared to enabling community involvement. A key aspect of this is that image data will be made available to the planetary community for science analysis as quickly as possible to encourage feedback and new ideas for targets.

Eliason, E.; Hansen, C. J.; McEwen, A.; Delamere, W. A.; Bridges, N.; Grant, J.; Gulich, V.; Herkenhoff, K.; Keszthelyi, L.; Kirk, R.

2003-01-01

471

When does pathogen evolution maximize the basic reproductive number in well-mixed host-pathogen systems?  

PubMed

Pathogen evolution towards the largest basic reproductive number, R0, has been observed in many theoretical models, but this conclusion does not hold universally. Previous studies of host-pathogen systems have defined general conditions under which R0 maximization occurs in terms of R0 itself. However, it is unclear what constraints these conditions impose on the functional forms of pathogen related processes (e.g. transmission, recover, or mortality) and how those constraints relate to the characteristics of natural systems. Here we focus on well-mixed SIR-type host-pathogen systems and, via a synthesis of results from the literature, we present a set of sufficient mathematical conditions under which evolution maximizes R0. Our conditions are in terms of the functional responses of the system and yield three general biological constraints on when R0 maximization will occur. First, there are no genotype-by-environment interactions. Second, the pathogen utilizes a single transmission pathway (i.e. either horizontal, vertical, or vector transmission). Third, when mortality is density dependent: (i) there is a single infectious class that individuals cannot recover from, (ii) mortality in the infectious class is entirely density dependent, and (iii) the rates of recovery, infection progression, and mortality in the exposed classes are independent of the pathogen trait. We discuss how this approach identifies the biological mechanisms that increase the dimension of the environmental feedback and prevent R0 maximization. PMID:23070214

Cortez, Michael H

2013-12-01

472

Coercive Sexual Experiences, Protective Behavioral Strategies, Alcohol Expectancies and Consumption among Male and Female College Students  

ERIC Educational Resources Information Center

Alcohol use and sexual assault on college campuses are highly prevalent and the focus of numerous prevention and intervention efforts. Our goals were to gain a greater understanding of the relationship between coercive sexual experiences, utilization of protective behavioral strategies and alcohol expectancies and consumption among male and female…

Palmer, Rebekka S.; McMahon, Thomas J.; Rounsaville, Bruce J.; Ball, Samuel A.

2010-01-01

473

The Occupational Aspirations and Expectations of Music Education Majors in Mexico  

ERIC Educational Resources Information Center

The purpose of this study was to investigate the occupational aspirations and expectations of students majoring in music education in Mexico. This study utilized the population of students majoring in music education at the National School of Music (NSM) at the National Autonomous University of Mexico. A questionnaire that was developed,…

Devroop, Karendra; Aguilar, Beatriz

2006-01-01

474

Realistic recruitment practices in organizations: The potential benefits of generalized expectancy calibration  

Microsoft Academic Search

Realistic Job Previews (RJPs) have been studied by researchers and utilized by practitioners to attenuate early turnover by providing both positive and negative information about a job and organization to job applicants. Historically, RJPs have suffered from several criticisms including modest effect sizes, cost of development, and potential self-selection effects. Recently, the expectancy lowering procedure (ELP: Buckley, Fedor, Veres, Wiese,

Brendan J. Morse; Paula M. Popovich

2009-01-01

475

Intrinsic Efficiency of Germanium: A Basis for Calculating Expected Detector Efficiency.  

National Technical Information Service (NTIS)

A method is presented whereby the intrinsic efficiency of Ge is utilized to calculate the expected peak efficiency of detectors having a wide range of sizes. The intrinsic efficiency of Ge, which is the probability for total absorption, was measured at 12...

M. G. Strauss I. S. Sherman M. J. Cattelino R. Brenner R. H. Pehl